Mitochondrial dysfunction is a hallmark of many genetic neurodegenerative diseases, but therapeutic options to reverse mitochondrial dysfunction are limited. While recent studies support the possibility of improving mitochondrial fusion/fission dynamics and motility to correct mitochondrial dysfunction and resulting neurodegeneration in Charcot-Marie-Tooth disease (CMT) and other neuropathies, the clinical utility of reported compounds and relevance of preclinical models are uncertain. Here, we describe motor and sensory neuron dysfunction characteristic of clinical CMT type 2 A in a CRISPR/Casp-engineered Mfn2 Thr105Met (T105M) mutant knock-in mouse. We further demonstrate that daily oral treatment with a novel mitofusin activator derived from the natural product piperine can reverse these neurologic phenotypes. Piperine derivative 8015 promoted mitochondrial fusion and motility in Mfn2-deficient cells in a mitofusin-dependent manner and reversed mitochondrial dysfunction in cultured fibroblasts and reprogrammed motor neurons from a human CMT2A patient carrying the MFN2 T105M mutation. Like previous mitofusin activators, 8015 exhibited stereospecific functionality, but the more active stereoisomer, 8015-P2, is unique in that it has subnanomolar potency and undergoes entero-hepatic recirculation which extends its in vivo half-life. Daily administration of 8015-P2 to Mfn2 T105M knock-in mice for 6 weeks normalized neuromuscular and sensory dysfunction and corrected histological/ultrastructural neurodegeneration and neurogenic myoatrophy. These studies describe a more clinically relevant mouse model of CMT2A and an improved mitofusin activator derived from piperine. We posit that 8015-P2 and other piperine derivatives may benefit CMT2A or other neurodegenerative conditions wherein mitochondrial dysdynamism plays a contributory role.

Glioblastoma (GBM) is a disease of the whole brain, with infiltrative tumor cells protected by an intact blood-brain barrier (BBB). GBM has a poor prognosis despite aggressive treatment, in part due to the lack of adequate drug permeability at the BBB. Standard of care GBM therapies include radiation and cytotoxic chemotherapy that lead to DNA damage. Subsequent activation of DNA damage response (DDR) pathways can induce resistance. Various DDR inhibitors, targeting the key regulators of these pathways such as ataxia telangiectasia mutated and Rad3-related (ATR), are being explored as radio- and chemosensitizers. Elimusertib, a novel ATR kinase inhibitor, can prevent repair of damaged DNA, increasing efficacy of DNA-damaging cytotoxic therapies. Robust synergy was observed in vitro when elimusertib was combined with the DNA-damaging agent temozolomide; however, we did not observe improvement with this combination in in vivo efficacy studies in GBM orthotopic tumor-bearing mice. This in vitro–in vivo disconnect was explored to understand factors influencing central nervous system (CNS) distribution of elimusertib and reasons for lack of efficacy. We observed that elimusertib is rapidly cleared from systemic circulation in mice and would not maintain adequate exposure in the CNS for efficacious combination therapy with temozolomide. CNS distribution of elimusertib is partially limited by P-glycoprotein efflux at the BBB, and high binding to CNS tissues leads to low levels of pharmacologically active (unbound) drug in the brain. Acknowledging the potential for interspecies differences in pharmacokinetics, these data suggest that clinical translation of elimusertib in combination with temozolomide for treatment of GBM may be limited.

Despite a significant decrease in the number of prescriptions for opioids, the opioid crisis continues, fueled in large part by the availability of the phenylpiperidine mu opioid receptor (MOR) agonist fentanyl. In contrast, the number of prescriptions for and the off-label use of gabapentinoids (gabapentin and pregabalin) has increased dramatically, with gabapentinoids commonly detected in opioid overdose victims. Although gabapentinoids can decrease the potency of the opioid receptor antagonist naloxone to reverse heroin-induced hypoventilation in male rats, the specificity and nature of interaction between gabapentinoids and MOR agonists and any potential sex difference in those interactions are not well characterized. Gabapentinoids were studied in female and male rats discriminating fentanyl (0.0032 mg/kg, i.p.) or cocaine (3.2 mg/kg, i.p.). Alone, neither gabapentin nor pregabalin significantly increased fentanyl- or cocaine-appropriate responding. In rats discriminating fentanyl, each gabapentinoid dose-dependently shifted the fentanyl and heroin discrimination dose-effect functions to the left, whereas naloxone dose-dependently shifted the fentanyl and heroin discrimination dose-effect functions to the right. Each gabapentinoid (100 mg/kg) significantly decreased the potency of naloxone to antagonize the discriminative stimulus effect of fentanyl or heroin. In contrast, each gabapentinoid dose-dependently shifted the cocaine and d-methamphetamine discrimination dose-effect functions to the right. There were no significant sex differences in this study. These results suggest that gabapentinoids impact the misuse of opioids, the co-use of opioids and stimulant drugs, and the increasing number of overdose deaths in individuals using opioids, stimulant drugs, and gabapentinoids in mixtures.

Previous studies demonstrated that sigma receptor (R) antagonists alone fail to alter cocaine self-administration despite blocking various other effects of cocaine. However, R antagonists when combined with dopamine transporter (DAT) inhibitors substantially decrease cocaine self-administration. To better understand the effects of this combination, the present study examined the effects of R antagonist and DAT inhibitor combinations in male rats discriminating cocaine (10 mg/kg, i.p.) from saline injections. The DAT inhibitors alone [(–)-2-β-carbomethoxy-3-β-(4-fluorophenyl)tropane 1,5-naphthalenedisulfonate monohydrate (WIN 35,428) and methylphenidate] at low (0.1-mg/kg) doses that were minimally active failed to shift the dose-effect function for discriminative-stimulus effects of cocaine to the left more than 2-fold. At 0.32 mg/kg the DAT inhibitors alone shifted the cocaine dose-effect function leftward 24- or 6.6-fold, respectively. The R antagonists (BD1008, BD1047, and BD1063) failed to fully substitute for cocaine, although BD1008 and BD1047 substituted partially. At 10 mg/kg, BD1008, BD1047, or BD1063 alone shifted the cocaine dose-effect function leftward less than 6.0-fold. In combination with 0.1 mg/kg WIN 35,428, the 10 mg/kg doses of R antagonists shifted the cocaine dose-effect function from 12.3- to 36.7-fold leftward, and with 0.32 mg/kg WIN 35,428 from 14.3- to 440-fold leftward. In combination with 0.1 mg/kg methylphenidate, those R antagonist doses shifted the cocaine dose-effect function from 5.5- to 55.0-fold leftward, and with 0.32 mg/kg methylphenidate from 10.5- to 48.1-fold leftward. The present results suggest that dual DAT/R inhibition produces agonist-like subjective effects that may promote decreases in self-administration obtained in previous studies.

Clinical reports suggest that the most effective strategies for managing opioid use disorder comprise a comprehensive treatment program of both pharmacological and nonpharmacological approaches. However, the conditions under which these combinations are most effective are not well characterized. This study examined whether the presence of an alternative reinforcer could alter the efficacy of Food and Drug Administration–approved opioid antagonist or agonist medications, as well as the nonopioid flumazenil, in decreasing oxycodone choice self-administration in nonhuman primates. Adult squirrel monkeys (n = 7; four females) responded under concurrent second-order fixed-ratio (FR)-3(FR5:S);TO45s schedules of reinforcement for intravenous oxycodone (0.1 mg/kg) or saline on one lever and 30% sweetened condensed milk or water on the other. Doses of naltrexone (0.00032–1.0 mg/kg), nalbuphine (0.32–10 mg/kg), buprenorphine (0.0032–0.032 mg/kg), methadone (0.32–1.0 mg/kg), or flumazenil (1–3.2 mg/kg) were administered intramuscularly prior to oxycodone self-administration sessions that occurred with either milk or water as the alternative. Naltrexone, a μ-opioid receptor antagonist, was >30-fold more potent when milk was available compared with water and abolished oxycodone intake (injections/session) while concomitantly increasing milk deliveries at the highest dose tested. Pretreatment with the low-efficacy μ-agonist nalbuphine was most effective in the presence of milk compared with water, decreasing oxycodone preference to <50% of control values. The higher efficacy μ-agonists, methadone and buprenorphine, and the benzodiazepine antagonist flumazenil did not appreciably alter the reinforcing potency of oxycodone under either condition. These results suggest that antagonist medications used in combination with alternative reinforcers may be an effective strategy to curtail opioid abuse–related behaviors.

Cannabinoid and opioid receptor activities can be modulated by a variety of post-translational mechanisms including the formation of interacting complexes. This study examines the involvement of endogenous and exogenous chaperones in modulating the abundance and activity of cannabinoid CB₁ receptor (CB₁R), opioid receptor (DOR), and CB₁R-DOR interacting complexes. Focusing on endogenous protein chaperones, namely receptor transporter proteins (RTPs), we examined relative mRNA expression in the mouse spinal cord and found RTP4 to be expressed at higher levels compared with other RTPs. Next, we assessed the effect of RTP4 on receptor abundance by manipulating RTP4 expression in cell lines. Overexpression of RTP4 causes an increase and knock-down causes a decrease in the levels of CB₁R, DOR, and CB₁R-DOR interacting complexes; this is accompanied by parallel changes in signaling. The ability of small molecule lipophilic ligands to function as exogenous chaperones was examined using receptor-selective antagonists. Long-term treatment leads to increases in receptor abundance and activity with no changes in mRNA supporting a role as pharmacological chaperones. Finally, the effect of cannabidiol (CBD), a small molecule ligand and a major active component of cannabis, on receptor abundance and activity in mice was examined. We find that CBD administration leads to increases in receptor abundance and activity in mouse spinal cord. Together, these results highlight a role for chaperones (proteins and small molecules) in modulating levels and activity of CB₁R, DOR, and their interacting complexes potentially through mechanisms including receptor maturation and trafficking.

Oxidative stress, fibrosis, and inflammasome activation from advanced glycation end product (AGE)–receptor of advanced glycation end product (RAGE) interaction contribute to diabetic cardiomyopathy (DCM) formation and progression. Our study revealed the impact of β-caryophyllene (BCP) on activating cannabinoid type 2 receptors (CB2Rs) against diabetic complication, mainly cardiomyopathy and investigated the underlying cell signaling pathways in mice. The murine model of DCM was developed by feeding a high-fat diet with streptozotocin injections. After the development of diabetes, the animals received a 12-week oral BCP treatment at a dose of 50 mg/kg/body weight. BCP treatment showed significant improvement in glucose tolerance and insulin resistance and enhanced serum insulin levels in diabetic animals. BCP treatment effectively reversed the heart remodeling and restored the phosphorylated troponin I and sarcoplasmic/endoplasmic reticulum Ca2+ ATPase 2a expression. Ultrastructural examination showed reduced myocardial cell injury in DCM mice treated with BCP. The preserved myocytes were found to be associated with reduced expression of AGE/RAGE in DCM mice hearts. BCP treatment mitigated oxidative stress by inhibiting expression of NADPH oxidase 4 and activating phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/nuclear factor erythroid 2–related factor 2 (Nrf2) signaling. Also, BCP suppressed cardiac fibrosis and endothelial-to-mesenchymal transition in DCM mice by inhibiting transforming growth factor β (TGF-β)/suppressor of mothers against decapentaplegic (Smad) signaling. Further, BCP treatment suppressed nucleotide-binding domain, leucine-rich–containing family, pyrin domain–containing-3 (NLRP3) inflammasome activation in DCM mice and alleviated cellular injury to the pancreatic tissues evidenced by significant elevation of the number of insulin-positive cells. To demonstrate a CB2R-dependent mechanism of BCP, another group of DCM mice were pretreated with AM630, a CB2R antagonist. AM630 was observed to abrogate the beneficial effects of BCP in DCM mice. Taken together, BCP demonstrated the potential to protect the myocardium and pancreas of DCM mice mediating CB2R-dependent mechanisms.

Patients with arthritis report using cannabis for pain management, and the major cannabinoid delta-9-tetrahydrocannabinol (⁹-THC) has anti-inflammatory properties, yet the effects of minor cannabinoids on arthritis are largely unknown. The goal of the present study was to determine the antiarthritic potential of the minor cannabinoid delta-8-tetrahydrocannabinol (⁸-THC) using the collagen-induced arthritis (CIA) mouse model. Adult male DBA/1J mice were immunized and boosted 21 days later with an emulsion of collagen and complete Freund’s adjuvant. Beginning on the day of the booster, mice were administered twice-daily injections of ⁸-THC (3 or 30 mg/kg), the steroid dexamethasone (2 mg/kg), or vehicle for two weeks. Dorsal-ventral paw thickness and qualitative measures of arthritis were recorded daily, and latency to fall from an inverted grid was measured on alternating days, to determine arthritis severity and functional impairment. On the final day of testing, spontaneous wire-climbing behavior and temperature preference in a thermal gradient ring were measured to assess CIA-depressed behavior. The ⁸-THC treatment (30 mg/kg) reduced paw swelling and qualitative signs of arthritis. ⁸-THC also blocked CIA-depressed climbing and CIA-induced preference for a heated floor without producing locomotor effects but did not affect latency to fall from a wire grid. In alignment with the morphologic and behavioral assessments in vivo, histology revealed that ⁸-THC reduced synovial inflammation, proteoglycan loss and cartilage and bone erosion in the foot joints in a dose-dependent manner. Together, these findings suggest that ⁸-THC not only blocked morphologic changes but also prevented functional loss caused by collagen-induced arthritis.

Chronic pain conditions affect nearly 20% of the population in the United States. Current medical interventions, such as opioid drugs, are effective at relieving pain but are accompanied by many undesirable side effects. This is one reason increased numbers of chronic pain patients have been turning to Cannabis for pain management. Cannabis contains many bioactive chemical compounds; however, current research looking into lesser-studied minor cannabinoids in Cannabis lacks uniformity between experimental groups and/or excludes female mice from investigation. This makes it challenging to draw conclusions between experiments done with different minor cannabinoid compounds between laboratories or parse out potential sex differences that could be present. We chose five minor cannabinoids found in lower quantities within Cannabis: cannabinol (CBN), cannabidivarin (CBDV), cannabigerol (CBG), 8-tetrahydrocannabinol (8-THC), and 9-tetrahydrocannabivarin (THCV). These compounds were then tested for their cannabimimetic and pain-relieving behaviors in a cannabinoid tetrad assay and a chemotherapy-induced peripheral neuropathy (CIPN) pain model in male and female CD-1 mice. We found that the minor cannabinoids we tested differed in the cannabimimetic behaviors evoked, as well as the extent. We found that CBN, CBG, and high-dose 8-THC evoked some tetrad behaviors in both sexes, while THCV and low-dose 8-THC exhibited cannabimimetic tetrad behaviors only in females. Only CBN efficaciously relieved CIPN pain, which contrasts with reports from other researchers. Together these findings provide further clarity to the pharmacology of minor cannabinoids and suggest further investigation into their mechanism and therapeutic potential.

The National Center for Complementary and Integrative Health (NCCIH), which is part of the US National Institutes of Health (NIH), has a broad interest in studying the biologic activities of natural products, especially those for which compelling evidence from preclinical research suggests biologic activities that may be beneficial to health or have a potential role in disease treatment, as well as products used extensively by the American public. As of 2023, use of cannabis for medical purposes is legal in 38 states and Washington, D.C. Such use continues to climb generally without sufficient knowledge regarding risks and benefits. In keeping with NCCIH’s natural product research priorities and recognizing this gap in knowledge, NCCIH formally launched a research program in 2019 to expand research on the possible benefits for pain management of certain substances found in cannabis: minor cannabinoids and terpenes. This Viewpoint provides additional details and the rationale for this research priority at NCCIH. In addition, NCCIH’s efforts and initiatives to facilitate and coordinate an NIH research agenda focused on cannabis and cannabinoid research are described.

Cannabis and its products have been used for centuries for both medicinal and recreational purposes. The recent widespread legalization of cannabis has vastly expanded its use in the United States across all demographics except for adolescents. Meanwhile, decades of research have advanced our knowledge of cannabis pharmacology and particularly of the endocannabinoid system with which the components of cannabis interact. This research has revealed multiple targets and approaches for manipulating the system for therapeutic use and to ameliorate cannabis toxicity or cannabis use disorder. Research has also led to new questions that underscore the potential risks of its widespread use, particularly the enduring consequences of exposure during critical windows of brain development or for consumption of large daily doses of cannabis with high content ⁹-tetrahydrocannabinol. This article highlights current neuroscience research on cannabis that has shed light on therapeutic opportunities and potential adverse consequences of misuse and points to gaps in knowledge that can guide future research.

Low-efficacy mu opioid receptor (MOR) agonists may serve as novel candidate analgesics with improved safety relative to high-efficacy opioids. This study used a recently validated assay of pain-depressed behavior in mice to evaluate a novel series of MOR-selective C9-substituted phenylmorphan opioids with graded MOR efficacies. Intraperitoneal injection of dilute lactic acid (IP acid) served as a noxious stimulus to depress locomotor activity by mice in an activity chamber composed of two compartments connected by an obstructed door. Behavioral measures included (1) crosses between compartments (vertical activity over the obstruction) and (2) movement counts quantified as photobeam breaks summed across compartments (horizontal activity). Each drug was tested alone and as a pretreatment to IP acid. A charcoal-meal test and whole-body-plethysmography assessment of breathing in 5% CO₂ were also used to assess gastrointestinal (GI) inhibition and respiratory depression, respectively. IP acid produced a concentration-dependent depression in crosses and movement that was optimally alleviated by intermediate- to low-efficacy phenylmorphans with sufficient efficacy to produce analgesia with minimal locomotor disruption. Follow-up studies with two low-efficacy phenylmorphans (JL-2-39 and DC-1-76.1) indicated that both drugs produced naltrexone-reversible antinociception with a rapid onset and a duration of ~1 h. Potency of both drugs increased when behavior was depressed by a lower IP-acid concentration, and neither drug alleviated behavioral depression by a non-pain stimulus (IP lithium chloride). Both drugs produced weaker GI inhibition and respiratory depression than fentanyl and attenuated fentanyl-induced GI inhibition and respiratory depression. Results support further consideration of selective, low-efficacy MOR agonists as candidate analgesics.

The aim of this study was to validate a previously developed deep learning model in 5 independent clinical trials. The predictive performance of this model was compared with the international prognostic index (IPI) and 2 models incorporating radiomic PET/CT features (clinical PET and PET models). Methods: In total, 1,132 diffuse large B-cell lymphoma patients were included: 296 for training and 836 for external validation. The primary outcome was 2-y time to progression. The deep learning model was trained on maximum-intensity projections from PET/CT scans. The clinical PET model included metabolic tumor volume, maximum distance from the bulkiest lesion to another lesion, SUV_peak, age, and performance status. The PET model included metabolic tumor volume, maximum distance from the bulkiest lesion to another lesion, and SUV_peak. Model performance was assessed using the area under the curve (AUC) and Kaplan–Meier curves. Results: The IPI yielded an AUC of 0.60 on all external data. The deep learning model yielded a significantly higher AUC of 0.66 (P < 0.01). For each individual clinical trial, the model was consistently better than IPI. Radiomic model AUCs remained higher for all clinical trials. The deep learning and clinical PET models showed equivalent performance (AUC, 0.69; P > 0.05). The PET model yielded the highest AUC of all models (AUC, 0.71; P < 0.05). Conclusion: The deep learning model predicted outcome in all trials with a higher performance than IPI and better survival curve separation. This model can predict treatment outcome in diffuse large B-cell lymphoma without tumor delineation but at the cost of a lower prognostic performance than with radiomics.

The Registry of Fast Myocardial Perfusion Imaging with Next-Generation SPECT (REFINE SPECT) has been expanded to include more patients and CT attenuation correction imaging. We present the design and initial results from the updated registry. Methods: The updated REFINE SPECT is a multicenter, international registry with clinical data and image files. SPECT images were processed by quantitative software and CT images by deep learning software detecting coronary artery calcium (CAC). Patients were followed for major adverse cardiovascular events (MACEs) (death, myocardial infarction, unstable angina, late revascularization). Results: The registry included scans from 45,252 patients from 13 centers (55.9% male, 64.7 ± 11.8 y). Correlating invasive coronary angiography was available for 3,786 (8.4%) patients. CT attenuation correction imaging was available for 13,405 patients. MACEs occurred in 6,514 (14.4%) patients during a median follow-up of 3.6 y (interquartile range, 2.5–4.8 y). Patients with a stress total perfusion deficit of 5% to less than 10% (unadjusted hazard ratio [HR], 2.42; 95% CI, 2.23–2.62) and a stress total perfusion deficit of at least 10% (unadjusted HR, 3.85; 95% CI, 3.56–4.16) were more likely to experience MACEs. Patients with a deep learning CAC score of 101–400 (unadjusted HR, 3.09; 95% CI, 2.57–3.72) and a CAC of more than 400 (unadjusted HR, 5.17; 95% CI, 4.41–6.05) were at increased risk of MACEs. Conclusion: The REFINE SPECT registry contains a comprehensive set of imaging and clinical variables. It will aid in understanding the value of SPECT myocardial perfusion imaging, leverage hybrid imaging, and facilitate validation of new artificial intelligence tools for improving prediction of adverse outcomes incorporating multimodality imaging.

The diagnostic work-up of patients with fever of unknown origin (FUO) begins with a thorough history and physical examination, complete blood count with differential, chest x-ray, urinalysis and culture, electrolyte panel, liver enzymes, erythrocyte sedimentation rate, and C-reactive protein level. Additional imaging procedures, including nuclear medicine tests, are generally used as second-line procedures, with ¹⁸F-FDG PET and PET/CT assuming increasingly important roles in the diagnostic work-up. The Society of Nuclear Medicine and Molecular Imaging, the Infectious Diseases Society of America, and the American College of Nuclear Medicine convened an autonomous expert work group to comprehensively review the published literature for nuclear imaging in adults and children with FUO and establish appropriate use criteria (AUC). This process was performed in accordance with the Protecting Access to Medicare Act of 2014, which requires that all referring physicians consult AUC by using a clinical decision support mechanism before ordering advanced diagnostic imaging services. The complete findings and discussions of the work group were published on January 8, 2023, and are available at https://www.snmmi.org/ClinicalPractice/content.aspx?ItemNumber=15666. The AUC in the final document are intended to assist referring health care providers in appropriate use of nuclear medicine imaging procedures in patients with FUO. The work group noted limitations in the current literature on nuclear medicine imaging for FUO, with the need for well-designed prospective multicenter investigations. Consensus findings from published data and expert opinions were used to create recommendations in common clinical scenarios for adults and children. Included in the complete document is a discussion of inflammation of unknown origin (IUO), a recently described entity. In view of the fact that the criteria for FUO and IUO are similar (except for fever > 38.3°C [100.9°F]) and that the most common etiologies of these 2 entities are similar, it is the expert opinion of the work group that the recommendations for nuclear medicine imaging of FUO are also applicable to IUO. These recommendations are included in the full guidance document. This summary reviews rationale, methodology, and main findings and refers the reader to the complete AUC document.

Neuroendocrine tumor (NET) metastases to the heart are found in 1%–4% of NET patients and have been reported primarily in the form of individual cases. We investigated the prevalence, clinical characteristics, imaging features, and outcomes of NET patients with cardiac metastases on ⁶⁸Ga-DOTATATE PET/CT. Methods: ⁶⁸Ga-DOTATATE PET/CT of 490 consecutive patients from a single institution were retrospectively reviewed for sites of metastases. The cumulative cardiovascular event rate and overall survival of patients with cardiac NET metastases (CNMs) were compared with those of a control group of metastatic NET patients without cardiac metastases. In patients with CNMs, the cardiac SUV_max with and without normalization to the myocardial background uptake was compared with a separate cohort of 11 patients with active cardiac sarcoidosis who underwent ⁶⁸Ga-DOTATATE PET/CT for research purposes. Results: In total, 270 patients with metastatic NETs were identified, 9 (3.3%) of whom had CNMs. All 9 patients had grade 1–2 gastroenteropancreatic NETs, most commonly from the small intestine (7 patients). The control group consisted of 140 patients with metastatic grade 1–2 gastroenteropancreatic NETs. On Kaplan–Meier analysis, there was no significant difference in the risk of cardiovascular adverse events (P = 0.91 on log-rank test) or mortality (P = 0.83) between the metastatic NET patients with and without cardiac metastases. The degree of cardiac DOTATATE uptake was significantly higher in CNMs than in patients with cardiac sarcoidosis without overlap, in terms of both cardiac SUV_max (P = 0.027) and SUV_max–to–myocardial background ratio (P = 0.021). Conclusion: Routine ⁶⁸Ga-DOTATATE PET/CT can be used to identify CNMs in 3% of patients with metastatic NETs. CNMs do not confer added cardiovascular or mortality risk. A distinguishing feature of CNMs is their high degree of DOTATATE uptake compared with focal myocardial inflammation.

The phase 3 VISION trial demonstrated that [¹⁷⁷Lu]Lu-PSMA-617 prolonged progression-free survival and overall survival (OS) in prostate-specific membrane antigen [PSMA]–positive metastatic castration-resistant prostate cancer (mCRPC) patients who progressed on taxane-based chemotherapy and androgen receptor–signaling inhibitors (ARSIs). The U.S. expanded-access program (EAP; NCT04825652) was opened to provide access to [¹⁷⁷Lu]Lu-PSMA-617 for eligible patients until regulatory approval was obtained. This study aimed to evaluate the efficacy and safety profile of [¹⁷⁷Lu]Lu-PSMA-617 within the EAP and compare the results with those from the VISION trial. Methods: Patients enrolled in the EAP at 4 institutions in the United States with available toxicity and outcome data were included. Outcome measures included OS, a prostate-specific antigen (PSA) response rate (RR) of at least 50%, and incidences of toxicity according to Common Terminology Criteria for Adverse Events version 5.0. Differences in baseline characteristics, outcome data, and toxicity between the EAP and VISION were evaluated using t testing of proportions and survival analyses. Results: In total, 117 patients with mCRPC who received [¹⁷⁷Lu]Lu-PSMA-617 within the EAP between May 2021 and March 2022 were eligible and included in this analysis. Patients enrolled in the EAP were more heavily pretreated with ARSI (≥2 ARSI regimens: 70% vs. 46%; P < 0.001) and had worse performance status at baseline (Eastern Cooperative Oncology Group score ≥ 2: 19% vs. 7%; P < 0.001) than VISION patients. EAP and VISION patients had similar levels of grade 3 or higher anemia (18% vs. 13%; P = 0.15), thrombocytopenia (13% vs. 8%; P = 0.13), and neutropenia (3% vs. 3%; P = 0.85) and similar PSA RRs (42% vs. 46%; P = 0.50) and OS (median: 15.1 vs. 15.3 mo; P > 0.05). Conclusion: Patients with PSMA-positive mCRPC who received [¹⁷⁷Lu]Lu-PSMA-617 within the EAP were later in their disease trajectory than VISION patients. Patients enrolled in the EAP achieved similar PSA RRs and OS and had a safety profile similar to that of the VISION trial patients.

Identifying cancer therapy resistance is a key time-saving tool for physicians. Part of chemotherapy resistance includes senescence, a persistent state without cell division or cell death. Chemically inducing senescence with the combination of trametinib and palbociclib (TP) yields several tumorigenic and prometastatic factors in pancreatic cancer models with many potential antibody-based targets. In particular, urokinase plasminogen activator receptor (uPAR) has been shown to be a membrane-bound marker of senescence in addition to an oncology target. Methods: Here, 2 antibodies against murine uPAR and human uPAR were developed as immuno-PET agents to noninvasively track uPAR antigen abundance. Results: TP treatment increased cell uptake both in murine KPC cells and in human MiaPaCa2 cells. In vivo, subcutaneously implanted murine KPC tumors had high tumor uptake with the antimurine uPAR antibody independently of TP in young mice, yet uPAR uptake was maintained in aged mice on TP. Mice xenografted with human MiaPaCa2 tumors showed a significant increase in tumor uptake on TP therapy when imaged with the antihuman uPAR antibody. Imaging with either uPAR antibody was found to be more tumor-selective than imaging with [¹⁸F]FDG or [¹⁸F]F-DPA-714. Conclusion: The use of radiolabeled uPAR-targeting antibodies provides a new antibody-based PET imaging candidate for pancreatic cancer imaging as well as chemotherapy-induced senescence.

This single-center, single-arm, phase II trial (ChiCTR2100050057) investigated the ability of ¹⁸F-labeled fibroblast activation protein inhibitor ([¹⁸F]AlF-NOTA-FAPI-04, denoted as ¹⁸F-FAPI) PET/CT to predict the response to neoadjuvant camrelizumab plus chemotherapy (nCC) in locally advanced esophageal squamous cell carcinoma (LA-ESCC). Methods: This study included 32 newly diagnosed LA-ESCC participants who underwent ¹⁸F-FAPI PET/CT at baseline, of whom 23 also underwent scanning after 2 cycles of nCC. The participants underwent surgery after 2 cycles of nCC. Recorded PET parameters included maximum, peak, and mean SUVs and tumor-to-background ratios (TBRs), metabolic tumor volume, and total lesion FAP expression. PET parameters were compared between patient groups with good and poor pathologic responses, and the predictive performance for treatment response was analyzed. Results: The good and poor response groups each included 16 participants (16/32, 50.0%). On ¹⁸F-FAPI PET/CT, the posttreatment SUVs were significantly lower in good responders than in poor responders, whereas the changes in SUVs with treatment were significantly higher (all P < 0.05). SUV_max (area under the curve [AUC], 0.87; P = 0.0026), SUV_peak (AUC, 0.89; P = 0.0017), SUV_mean (AUC, 0.88; P = 0.0021), TBR_max (AUC, 0.86; P = 0.0031), and TBR_mean (AUC, 0.88; P = 0.0021) after nCC were significant predictors of pathologic response to nCC, with sensitivities of 63.64%–81.82% and specificities of 83.33%–100%. Changes in SUV_max (AUC, 0.81; P = 0.0116), SUV_peak (AUC, 0.82; P = 0.0097), SUV_mean (AUC, 0.81; P = 0.0116), and TBR_mean (AUC, 0.74; P = 0.0489) also were significant predictors of the pathologic response to nCC, with sensitivities and specificities in similar ranges. Conclusion: ¹⁸F-FAPI PET/CT parameters after treatment and their changes from baseline can predict the pathologic response to nCC in LA-ESCC participants.

In several malignancies, only a limited number of patients respond to immune checkpoint inhibitors. Predicting and monitoring responses to these inhibitors represent an unmet clinical need. Here, we developed a PET/CT probe targeting granzyme B, [⁶⁸Ga]Ga-NOTA-Gly-Gly-Gly-Ile-Glu-Pro-Asp-CHO (GSI), and aimed to investigate whether it can be used to monitor the effects of immune checkpoint inhibitors early in the course of therapy. Methods: Seventy-two patients with gastric cancer (stages III–IV) were recruited for [⁶⁸Ga]Ga-NOTA-GSI PET/CT imaging after 2 or 3 cycles of the immunotherapy, and 40 patients were included in the final analysis. The SUV_max of primary tumors (SUV_max-t), SUV_max of metastatic lymph nodes (SUV_max-LN), and SUV_max of normal tissues (liver and blood pool) were measured, and their target-to-liver background ratio (TLR) and target-to-blood background ratio (TBR) were denoted for primary tumors as TLR_tumor and TBR_tumor and for metastatic lymph nodes as TLR_LN and TBR_LN, respectively. The treatment responses were assessed within 1 wk after full-course treatment according to RECIST version 1.1. Wilcoxon rank-sum tests were used to compare the PET/CT parameters between responders and nonresponders. Receiver operating characteristic curve analysis was used to assess the diagnostic efficacy of [⁶⁸Ga]Ga-NOTA-GSI PET/CT parameters in identifying responders. Two-tailed P value of less than 0.05 was considered statistically significant. Results: We found that SUV_max-t, TLR_tumor, TBR_tumor, SUV_max-LN, and TBR_LN were higher in responders than in nonresponders (2.49 ± 0.58 vs. 1.55 ± 0.48, P = 0.000; 2.24 ± 0.48 vs. 1.74 ± 0.67, P = 0.007; 1.38 ± 0.43 vs. 0.90 ± 0.23, P = 0.000; 2.24 ± 0.99 vs. 1.42 ± 0.55, P = 0.003; and 1.28 ± 0.68 vs. 0.83 ± 0.32, P = 0.012, respectively). According to receiver operating characteristic curve analysis, the area under the curve for SUV_max-t, TBR_tumor, TLR_tumor, SUV_max-LN, TLR_LN, and TBR_LN was 0.886, 0.866, 0.746, 0.772, 0.648, and 0.731, respectively. The threshold of SUV_max-t was 2.05, and its sensitivity and specificity were 81.0% and 84.2%, respectively. In addition, multivariate logistic regression indicated that TBR_tumor was an independent predictor of treatment response (P = 0.03). Conclusion: Our results indicated that [⁶⁸Ga]Ga-NOTA-GSI PET/CT is a promising tool for predicting early response to combined immunotherapy in gastric cancer patients.

Optimal patient management protocols for metastatic castration-resistant prostate cancer (mCRPC) are poorly defined and even further complexified with new therapy approvals, such as radiopharmaceuticals. The prostate-specific membrane antigen (PSMA)–targeted agent ¹⁷⁷Lu vipivotide tetraxetan ([¹⁷⁷Lu]Lu-PSMA-617), approved after the phase III VISION study, presents physicians with additional aspects of patient management, including specific adverse event (AE) monitoring and management, as well as radiation safety. Drawing on our experience as VISION study investigators, here we provide guidance on best practices for delivering PSMA-targeted radiopharmaceutical therapy (RPT) to patients with mCRPC. After a comprehensive review of published evidence and guidelines on RPT management in prostate cancer, we identified educational gaps in managing the radiation safety and AEs associated with [¹⁷⁷Lu]Lu-PSMA-617. Our results showed that providing sufficient education on AEs (e.g., fatigue and dry mouth) and radiation safety principles is key to effective delivery and management of patient expectations. Patient counseling by health care professionals, across disciplines, is a cornerstone of optimal patient management during PSMA-targeted RPT. Multidisciplinary collaboration is crucial, and physicians must adhere to radiation safety protocols and counsel patients on radiation safety considerations. Treatment with [¹⁷⁷Lu]Lu-PSMA-617 is generally well tolerated; however, additional interventions may be required, such as dosing modification, medications, or transfusions. Urinary incontinence can be challenging in the context of radiation safety. Multidisciplinary collaboration between medical oncologists and nuclear medicine teams ensures that patients are monitored and managed safely and efficiently. In clinical practice, the benefit-to-risk ratio should always be evaluated on a case-by-case basis.

gp130 functions as a shared signal-transducing subunit not only for interleukin (IL)-6 but also for eight other human cytokine receptor complexes. The IL-6 signaling pathway mediated through gp130 encompasses classical, trans, or cluster signaling, intricately regulated by a diverse array of modulators affecting IL-6, its receptor, and gp130. Currently, only a limited number of small molecule antagonists and agonists for gp130 are known. This review aims to comprehensively examine the current knowledge of these modulators and provide insights into their pharmacological properties, particularly in the context of cancer and other diseases. Notably, the prominent gp130 modulators SC144, bazedoxifene, and raloxifene are discussed in detail, with a specific focus on the discovery of SC144’s iron-chelating properties. This adds a new dimension to the understanding of its pharmacological effects and therapeutic potential in conditions where iron homeostasis is significant. Our bioinformatic analysis of gp130 and genes related to iron homeostasis reveals insightful correlations, implicating the role of iron in the gp130 signaling pathway. Overall, this review contributes to the evolving understanding of gp130 modulation and its potential therapeutic applications in various disease contexts.

Historically, the intestinal lymphatics were considered passive conduits for fluids, immune cells, dietary lipids, lipid soluble vitamins, and lipophilic drugs. Studies of intestinal lymphatic drug delivery in the late 20th century focused primarily on the drugs’ physicochemical properties, especially high lipophilicity, that resulted in intestinal lymphatic transport. More recent discoveries have changed our traditional view by demonstrating that the lymphatics are active, plastic, and tissue-specific players in a range of biological and pathological processes, including within the intestine. These findings have, in turn, inspired exploration of lymph-specific therapies for a range of diseases, as well as the development of more sophisticated strategies to actively deliver drugs or vaccines to the intestinal lymph, including a range of nanotechnologies, lipid prodrugs, and lipid-conjugated materials that "hitchhike" onto lymphatic transport pathways. With the increasing development of novel therapeutics such as biologics, there has been interest in whether these therapeutics are absorbed and transported through intestinal lymph after oral administration. Here we review the current state of understanding of the anatomy and physiology of the gastrointestinal lymphatic system in health and disease, with a focus on aspects relevant to drug delivery. We summarize the current state-of-the-art approaches to deliver drugs and quantify their uptake into the intestinal lymphatic system. Finally, and excitingly, we discuss recent examples of significant pharmacokinetic and therapeutic benefits achieved via intestinal lymphatic drug delivery. We also propose approaches to advance the development and clinical application of intestinal lymphatic delivery strategies in the future.

Over 4 decades of research support the link between Alzheimer disease (AD) and somatostatin [somatotropin-releasing inhibitory factor (SRIF)]. SRIF and SRIF-expressing neurons play an essential role in brain function, modulating hippocampal activity and memory formation. Loss of SRIF and SRIF-expressing neurons in the brain rests at the center of a series of interdependent pathological events driven by amyloid-β peptide (Aβ), culminating in cognitive decline and dementia. The connection between the SRIF and AD further extends to the neuropsychiatric symptoms, seizure activity, and inflammation, whereas preclinical AD investigations show SRIF or SRIF receptor agonist administration capable of enhancing cognition. SRIF receptor subtype-4 activation in particular presents unique attributes, with the potential to mitigate learning and memory decline, reduce comorbid symptoms, and enhance enzymatic degradation of Aβ in the brain. Here, we review the links between SRIF and AD along with the therapeutic implications.

α-Synuclein (α-Syn) aggregation in Lewy bodies and Lewy neurites has emerged as a key pathogenetic feature in Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. Various factors, including posttranslational modifications (PTMs), can influence the propensity of α-Syn to misfold and aggregate. PTMs are biochemical modifications of a protein that occur during or after translation and are typically mediated by enzymes. PTMs modulate several characteristics of proteins including their structure, activity, localization, and stability. α-Syn undergoes various posttranslational modifications, including phosphorylation, ubiquitination, SUMOylation, acetylation, glycation, O-GlcNAcylation, nitration, oxidation, polyamination, arginylation, and truncation. Different PTMs of a protein can physically interact with one another or work together to influence a particular physiological or pathological feature in a process known as PTMs crosstalk. The development of detection techniques for the cooccurrence of PTMs in recent years has uncovered previously unappreciated mechanisms of their crosstalk. This has led to the emergence of evidence supporting an association between α-Syn PTMs crosstalk and synucleinopathies. In this review, we provide a comprehensive evaluation of α-Syn PTMs, their impact on misfolding and pathogenicity, the pharmacological means of targeting them, and their potential as biomarkers of disease. We also highlight the importance of the crosstalk between these PTMs in α-Syn function and aggregation. Insight into these PTMS and the complexities of their crosstalk can improve our understanding of the pathogenesis of synucleinopathies and identify novel targets of therapeutic potential.

Bile acids are the end products of cholesterol catabolism. Hepatic bile acid synthesis accounts for a major fraction of daily cholesterol turnover in humans. Biliary secretion of bile acids generates bile flow and facilitates biliary secretion of lipids, endogenous metabolites, and xenobiotics. In intestine, bile acids facilitate the digestion and absorption of dietary lipids and fat-soluble vitamins. Through activation of nuclear receptors and G protein-coupled receptors and interaction with gut microbiome, bile acids critically regulate host metabolism and innate and adaptive immunity and are involved in the pathogenesis of cholestasis, metabolic dysfunction-associated steatotic liver disease, alcohol-associated liver disease, type-2 diabetes, and inflammatory bowel diseases. Bile acids and their derivatives have been developed as potential therapeutic agents for treating chronic metabolic and inflammatory liver diseases and gastrointestinal disorders.

This review explores the concept of synergy in pharmacology, emphasizing its importance in optimizing treatment outcomes through the combination of drugs with different mechanisms of action. Synergy, defined as an effect greater than the expected additive effect elicited by individual agents according to specific predictive models, offers a promising approach to enhance therapeutic efficacy while minimizing adverse events. The historical evolution of synergy research, from ancient civilizations to modern pharmacology, highlights the ongoing quest to understand and harness synergistic interactions. Key concepts, such as concentration-response curves, additive effects, and predictive models, are discussed in detail, emphasizing the need for accurate assessment methods throughout translational drug development. Although various mathematical models exist for synergy analysis, selecting the appropriate model and software tools remains a challenge, necessitating careful consideration of experimental design and data interpretation. Furthermore, this review addresses practical considerations in synergy assessment, including preclinical and clinical approaches, mechanism of action, and statistical analysis. Optimizing synergy requires attention to concentration/dose ratios, target site localization, and timing of drug administration, ensuring that the benefits of combination therapy detected bench-side are translatable into clinical practice. Overall, the review advocates for a systematic approach to synergy assessment, incorporating robust statistical analysis, effective and simplified predictive models, and collaborative efforts across pivotal sectors, such as academic institutions, pharmaceutical companies, and regulatory agencies. By overcoming critical challenges and maximizing therapeutic potential, effective synergy assessment in drug development holds promise for advancing patient care.

Multiple sclerosis (MS) is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system (CNS), with a putative autoimmune origin and complex pathogenesis. Modification of the natural history of MS by reducing relapses and slowing disability accumulation was first attained in the 1990 s with the development of the first-generation disease-modifying therapies. Glatiramer acetate (GA), a copolymer of L-alanine, L-lysine, L-glutamic acid, and L-tyrosine, was discovered due to its ability to suppress the animal model of MS, experimental autoimmune encephalomyelitis. Extensive clinical trials and long-term assessments established the efficacy and the safety of GA. Furthermore, studies of the therapeutic processes induced by GA in animal models and in MS patients indicate that GA affects various levels of the innate and the adaptive immune response, generating deviation from proinflammatory to anti-inflammatory pathways. This includes competition for binding to antigen presenting cells; driving dendritic cells, monocytes, and B-cells toward anti-inflammatory responses; and stimulating T-helper 2 and T-regulatory cells. The immune cells stimulated by GA reach the CNS and secrete in situ anti-inflammatory cytokines alleviating the pathological processes. Furthermore, cumulative findings reveal that in addition to its immunomodulatory effect, GA promotes neuroprotective repair processes such as neurotrophic factors secretion, remyelination, and neurogenesis. This review aims to provide an overview of MS pathology diagnosis and treatment as well as the diverse mechanism of action of GA.

Our knowledge of the roles of individual cytochrome P450 (P450) enzymes in drug metabolism has developed considerably in the past 30 years, and this base has been of considerable use in avoiding serious issues with drug interactions and issues due to variations. Some newer approaches are being considered for "phenotyping" metabolism reactions with new drug candidates. Endogenous biomarkers are being used for noninvasive estimation of levels of individual P450 enzymes. There is also the matter of some remaining "orphan" P450s, which have yet to be assigned reactions. Practical problems that continue in drug development include predicting drug-drug interactions, predicting the effects of polymorphic and other P450 variations, and evaluating interspecies differences in drug metabolism, particularly in the context of "metabolism in safety testing" regulatory issues ["disproportionate (human) metabolites"].

Karolinska Institutet is a medical university encompassing 21 departments distributed across three departmental or campus groups. Pharmacological research has a long and successful tradition at the institute with a multitude of seminal findings in the areas of neuronal control of vasodilatation, cardiovascular pharmacology, neuropsychopharmacology, receptor pharmacology, and pharmacogenomics that resulted in, among many other recognitions, two Nobel prizes in Physiology and Medicine, one in 1970 to Ulf von Euler for his discovery of the processes involved in storage, release, and inactivation of neurotransmitters and the other in 1982 to Sune Bergström and Bengt Samuelsson for their work on prostaglandins and the discovery of leukotrienes. Pharmacology at Karolinska Institutet has over the last decade been ranked globally among the top 10 according to the QS World University Ranking. With the Department of Physiology and Pharmacology now celebrating its 75-year anniversary, we wanted to take this as an opportunity to showcase recent research achievements and how they paved the way for current activities at the department. We emphasize examples from preclinical and clinical research where the dpartment's integrative environment and robust infrastructure have successfully facilitated the translation of findings into clinical applications and patient benefits. The close collaboration between preclinical scientists and clinical researchers across various disciplines, along with a strong network of partnerships within the department and beyond, positions us to continue leading world-class pharmacological research at the Department of Physiology and Pharmacology for decades to come.

Hearing disorders pose significant challenges to individuals experiencing them and their overall quality of life, emphasizing the critical need for advanced pharmacological approaches to address these conditions. Current treatment options often focus on amplification devices, cochlear implants, or other rehabilitative therapies, leaving a substantial gap regarding effective pharmacological interventions. Advancements in our understanding of the molecular and cellular mechanisms involved in hearing disorders induced by noise, aging, and ototoxicity have opened new avenues for drug development, some of which have led to numerous clinical trials, with promising results. The development of optimal drug delivery solutions in animals and humans can also enhance the targeted delivery of medications to the ear. Moreover, large genome studies contributing to a genetic understanding of hearing loss in humans combined with advanced molecular technologies in animal studies have shown a great potential to increase our understanding of the etiologies of hearing loss. The auditory system exhibits circadian rhythms and temporal variations in its physiology, its vulnerability to auditory insults, and its responsiveness to drug treatments. The cochlear clock rhythms are under the control of the glucocorticoid system, and preclinical evidence suggests that the risk/benefit profile of hearing disorder treatments using chronopharmacological approaches would be beneficial. If translatable to the bedside, such approaches may improve the outcome of clinical trials. Ongoing research into the molecular and genetic basis of auditory disorders, coupled with advancements in drug formulation and delivery as well as optimized timing of drug administration, holds great promise of more effective treatments.

Nitric oxide (NO) from endothelial NO synthase importantly contributes to vascular homeostasis. Reduced NO production or increased scavenging during disease conditions with oxidative stress contribute to endothelial dysfunction and NO deficiency. In addition to the classical enzymatic NO synthases (NOS) system, NO can also be generated via the nitrate-nitrite-NO pathway. Dietary and pharmacological approaches aimed at increasing NO bioactivity, especially in the cardiovascular system, have been the focus of much research since the discovery of this small gaseous signaling molecule. Despite wide appreciation of the biological role of NOS/NO signaling, questions still remain about the chemical nature of NOS-derived bioactivity. Recent studies show that NO-like bioactivity can be efficiently transduced by mobile NO-ferroheme species, which can transfer between proteins, partition into a hydrophobic phase, and directly activate the soluble guanylyl cyclase-cGMP-protein kinase G pathway without intermediacy of free NO. Moreover, interaction between red blood cells and the endothelium in the regulation of vascular NO homeostasis have gained much attention, especially in conditions with cardiometabolic disease. In this review we discuss both classical and nonclassical pathways for NO generation in the cardiovascular system and how these can be modulated for therapeutic purposes.

The class F of G protein-coupled receptors (GPCRs) consists of 10 Frizzleds (FZD_1–10) and Smoothened (SMO). FZDs bind and are activated by secreted lipoglycoproteins of the Wingless/Int-1 (WNT) family, and SMO is indirectly activated by the Hedgehog (Hh) family of morphogens acting on the transmembrane protein Patched. The advance of our understanding of FZDs and SMO as dynamic transmembrane receptors and molecular machines, which emerged during the past 14 years since the first-class F GPCR IUPHAR nomenclature report, justifies an update. This article focuses on the advances in molecular pharmacology and structural biology providing new mechanistic insight into ligand recognition, receptor activation mechanisms, signal initiation, and signal specification. Furthermore, class F GPCRs continue to develop as drug targets, and novel technologies and tools such as genetically encoded biosensors and CRISP/Cas9 edited cell systems have contributed to refined functional analysis of these receptors. Also, advances in crystal structure analysis and cryogenic electron microscopy contribute to the rapid development of our knowledge about structure-function relationships, providing a great starting point for drug development. Despite the progress, questions and challenges remain to fully understand the complexity of the WNT/FZD and Hh/SMO signaling systems.

Both preclinical and clinical studies implicate functional impairments of several neuroactive metabolites of the kynurenine pathway (KP), the major degradative cascade of the essential amino acid tryptophan in mammals, in the pathophysiology of neurologic and psychiatric diseases. A number of KP enzymes, such as tryptophan 2,3-dioxygenase (TDO2), indoleamine 2,3-dioxygenases (IDO1 and IDO2), kynurenine aminotransferases (KATs), kynurenine 3-monooxygenase (KMO), 3-hydroxyanthranilic acid oxygenase (3-HAO), and quinolinic acid phosphoribosyltransferase (QPRT), control brain KP metabolism in health and disease and are therefore increasingly considered to be promising targets for the treatment of disorders of the nervous system. Understanding the distribution, cellular expression, and regulation of KP enzymes and KP metabolites in the brain is therefore critical for the conceptualization and implementation of successful therapeutic strategies.

BACKGROUND AND PURPOSE:

Low-field 64 mT portable brain MRI has recently shown diagnostic promise for MS. This study aimed to evaluate the utility of portable MRI (pMRI) in assessing dissemination in space (DIS) in patients presenting with optic neuritis and determine whether deploying pMRI in the MS clinic can shorten the time from symptom onset to MRI.

BACKGROUND AND PURPOSE:

A cleftlike nonenhancing hypointensity was observed repeatedly in the pituitary gland at the adenohypophysis/neurohypophysis border on contrast-enhanced 3D fat-saturated T1-MPRAGE using clinical 7T MRI. Our primary goal was to assess the prevalence of this finding. The secondary goals were to evaluate the frequency of other incidental pituitary lesions, MRI artifacts, and their effect on pituitary imaging on the contrast-enhanced 3D fat-saturated T1 MPRAGE at 7T.

BACKGROUND AND PURPOSE:

Neuronal ceroid lipofuscinoses are a group of neurodegenerative disorders. Recently, enzyme replacement therapy (ERT) was approved for neuronal ceroid lipofuscinosis type 2 (CLN2), a subtype of neuronal ceroid lipofuscinoses. The aim of this study was to quantify brain volume loss in CLN2 disease in patients on ERT in comparison with a natural history cohort using MRI.

BACKGROUND AND PURPOSE:

Hemangioblastoma is a rare vascular tumor that occurs within the central nervous system in children. Differentiating hemangioblastoma from other posterior fossa tumors can be challenging on imaging, and preoperative diagnosis can change the neurosurgical approach. We hypothesize that a "lightbulb sign" on the arterial spin-labeling (ASL) sequence (diffuse homogeneous intense hyperperfusion within the solid component of the tumor) will provide additional imaging finding to differentiate hemangioblastoma from other posterior fossa tumors.

BACKGROUND AND PURPOSE:

World Health Organization (WHO) grade 2 and 3 diffuse gliomas account for approximately 5% of primary brain tumors. They are invasive and infiltrative tumors and have considerable morbidity, causing progressive neurologic deterioration. The mean survival time is <10 years from diagnosis. Surgical debulking represents first-line management. The extent of resection is associated with progression-free and overall survival. Radiologic assessment of the extent of resection is challenging. This can be underestimated on early postoperative MRI, meaning that accurate assessment may be achieved only on delayed follow-up imaging. We hypothesized that DWI may help facilitate more reliable estimates of the extent of resection on early postoperative MRI. This study aimed to assess the utility of DWI in early postoperative MRI to evaluate the extent of resection.

BACKGROUND AND PURPOSE:

Gadolinium-based contrast agents are widely used for meningioma imaging; however, concerns exist regarding their side effects, cost, and environmental impact. At the standard gadolinium dose, most meningiomas show avid contrast enhancement, suggesting that administering a smaller dose may be feasible. The purpose of this study was to evaluate the impact of a lower gadolinium dose on the differentiation between meningiomas and adjacent intracranial tissues.

BACKGROUND AND PURPOSE:

Preoperative assessment of meningioma consistency is beneficial for optimizing surgical strategy and prognosis of patients. We aim to develop a noninvasive prediction model for meningioma consistency utilizing MR elastography and DTI.

BACKGROUND AND PURPOSE:

Previous studies have reported metal accumulation and microstructure changes in deep gray nuclei (DGN) in Wilson disease (WD). However, there are limited studies that investigate whether there is metal accumulation and microstructure changes in DGN of patients with WD with normal-appearing routine MRI. This study aimed to evaluate multiparametric changes in DGN of WD and whether the findings correlate with clinical severity in patients with WD.