David E. Cummings
Aug 1, 2001; 50:1714-1719
Rapid Publications

Thomas A. Buchanan
Sep 1, 2002; 51:2796-2803
Pathophysiology

ME Griffin
Jun 1, 1999; 48:1270-1274
Articles

David E. Kelley
Oct 1, 2002; 51:2944-2950
Metabolism and Signal Transduction

Lipodystrophies are a group of disorders characterized by absence or loss of adipose tissue and abnormal fat distribution, commonly accompanied by metabolic dysregulation. Although considered rare disorders, their prevalence in the general population is not well understood. We aimed to evaluate the clinical and genetic prevalence of lipodystrophy disorders in a large clinical care cohort. We interrogated the electronic health record (EHR) information of >1.3 million adults from the Geisinger Health System for lipodystrophy diagnostic codes. We estimate a clinical prevalence of disease of 1 in 20,000 individuals. We performed genetic analyses in individuals with available genomic data to identify variants associated with inherited lipodystrophies and examined their EHR for comorbidities associated with lipodystrophy. We identified 16 individuals carrying the p.R482Q pathogenic variant in LMNA associated with Dunnigan familial partial lipodystrophy. Four had a clinical diagnosis of lipodystrophy, whereas the remaining had no documented clinical diagnosis despite having accompanying metabolic abnormalities. We observed a lipodystrophy-associated variant carrier frequency of 1 in 3,082 individuals in our cohort with substantial burden of metabolic dysregulation. We estimate a genetic prevalence of disease of ~1 in 7,000 in the general population. Partial lipodystrophy is an underdiagnosed condition. and its prevalence, as defined molecularly, is higher than previously reported. Genetically guided stratification of patients with common metabolic disorders, like diabetes and dyslipidemia, is an important step toward precision medicine.

The placenta participates in maternal insulin sensitivity changes during pregnancy; however, mechanisms remain unclear. We investigated associations between maternal insulin sensitivity and placental DNA methylation markers across the genome. We analyzed data from 430 mother-offspring dyads in the Gen3G cohort. All women underwent 75-g oral glucose tolerance tests at ~26 weeks of gestation; we used glucose and insulin measures to estimate insulin sensitivity (Matsuda index). At delivery, we collected samples from placenta (fetal side) and measured DNA methylation using Illumina EPIC arrays. Using linear regression models to quantify associations at 720,077 cytosine-guanine dinucleotides (CpGs), with adjustment for maternal age, gravidity, smoking, BMI, child sex, and gestational age at delivery, we identified 188 CpG sites where placental DNA methylation was associated with Matsuda index (P < 6.94 x 10^–8). Among genes annotated to these 188 CpGs, we found enrichment in targets for miRNAs, in histone modifications, and in parent-of-origin DNA methylation including the H19/MIR675 locus (paternally imprinted). We identified 12 known placenta imprinted genes, including KCNQ1. Mendelian randomization analyses revealed five loci where placenta DNA methylation may causally influence maternal insulin sensitivity, including the maternally imprinted gene DLGAP2. Our results suggest that placental DNA methylation is fundamentally linked to the regulation of maternal insulin sensitivity in pregnancy.

Permanent neonatal diabetes mellitus (PNDM) is caused by reduced β-cell number or impaired β-cell function. Understanding of the genetic basis of this disorder highlights fundamental β-cell mechanisms. We performed trio genome sequencing for 44 patients with PNDM and their unaffected parents to identify causative de novo variants. Replication studies were performed in 188 patients diagnosed with diabetes before 2 years of age without a genetic diagnosis. EIF2B1 (encoding the eIF2B complex α subunit) was the only gene with novel de novo variants (all missense) in at least three patients. Replication studies identified two further patients with de novo EIF2B1 variants. In addition to having diabetes, four of five patients had hepatitis-like episodes in childhood. The EIF2B1 de novo mutations were found to map to the same protein surface. We propose that these variants render the eIF2B complex insensitive to eIF2 phosphorylation, which occurs under stress conditions and triggers expression of stress response genes. Failure of eIF2B to sense eIF2 phosphorylation likely leads to unregulated unfolded protein response and cell death. Our results establish de novo EIF2B1 mutations as a novel cause of permanent diabetes and liver dysfunction. These findings confirm the importance of cell stress regulation for β-cells and highlight EIF2B1’s fundamental role within this pathway.

Children at increased genetic risk for type 1 diabetes (T1D) after environmental exposures may develop pancreatic islet autoantibodies (IA) at a very young age. Metabolic profile changes over time may imply responses to exposures and signal development of the first IA. Our present research in The Environmental Determinants of Diabetes in the Young (TEDDY) study aimed to identify metabolome-wide signals preceding the first IA against GAD (GADA-first) or against insulin (IAA-first). We profiled metabolomes by mass spectrometry from children’s plasma at 3-month intervals after birth until appearance of the first IA. A trajectory analysis discovered each first IA preceded by reduced amino acid proline and branched-chain amino acids (BCAAs), respectively. With independent time point analysis following birth, we discovered dehydroascorbic acid (DHAA) contributing to the risk of each first IA, and -aminobutyric acid (GABAs) associated with the first autoantibody against insulin (IAA-first). Methionine and alanine, compounds produced in BCAA metabolism and fatty acids, also preceded IA at different time points. Unsaturated triglycerides and phosphatidylethanolamines decreased in abundance before appearance of either autoantibody. Our findings suggest that IAA-first and GADA-first are heralded by different patterns of DHAA, GABA, multiple amino acids, and fatty acids, which may be important to primary prevention of T1D.

Long-term hyperglycemia in patients with diabetes leads to human serum albumin (HSA) glycation, which may impair HSA function as a transport protein and affect the therapeutic efficacy of anticoagulants in patients with diabetes. In this study, a novel mass spectrometry approach was developed to reveal the differences in the profiles of HSA glycation sites between patients with diabetes and healthy subjects. K199 was the glycation site most significantly changed in patients with diabetes, contributing to different interactions of glycated HSA and normal HSA with two types of anticoagulant drugs, heparin and warfarin. An in vitro experiment showed that the binding affinity to warfarin became stronger when HSA was glycated, while HSA binding to heparin was not significantly influenced by glycation. A pharmacokinetic study showed a decreased level of free warfarin in the plasma of diabetic rats. A preliminary retrospective clinical study also revealed that there was a statistically significant difference in the anticoagulant efficacy between patients with diabetes and patients without diabetes who had been treated with warfarin. Our work suggests that larger studies are needed to provide additional specific guidance for patients with diabetes when they are administered anticoagulant drugs or drugs for treating other chronic diseases.

Edmond Campbell/Senior Parliamentary Reporter Conceding that healthcare workers in the public sector are burnt out as they combat COVID-19, Health and Wellness Minister Dr Christopher Tufton says the Government is taking steps to boost its...

Days after The Gleaner reported a clarion call from Port Maria Mayor Richard Creary for the quarantine of St Mary communities owing to growing concerns about the spread of COVID-19 in the parish, the Government responded with the lockdown of three...

Many taxi and bus operators in sections of Kingston and St Andrew are seemingly adhering to social-distancing guidelines outlined by the Government for the sector, in terms of the number of passengers they are allowed to transport at a time. These...

The wet weather last Saturday (May 2) could not dampen the spirits of award-winning gospel artiste and ordained evangelist Kevin Downswell as he ventured into the St Catherine community of Central Village, where he spent some of his formative years...

The Senate on Friday paid tribute to distinguished consultant psychiatrist, Frederick Hickling, for his tremendous contribution to persons with intellectual disabilities. Hickling died on Thursday. Senator Dr Saphire Longmore remembered Professor...

Vendors and store operators who would normally score big on Mother’s Day baskets are lamenting that the novel coronavirus has put a dent in their sales. Kaydyonne Thomas, owner of a gift store in the Pavilion Mall, located in Half Way Tree, said...

Director of the Pan American Health Organization (PAHO), Dr Carissa F. Etienne, today called for accelerated and expanded testing for COVID-19 in countries of the Americas. “We need a clearer view of where the virus is circulating and how...

BRIDGETOWN, Barbados, CMC – The Barbados-based the Caribbean Disaster Emergency Management Agency (CDEMA) says its executive director, Ronald Jackson, is leaving the post after seven years “of unwavering and exemplary service to the...

KINGSTOWN, St Vincent, CMC – The St Vincent and the Grenadines Government has denied a United States-based airline permission to land, dashing hopes that an estimated 300 nationals employed with a US-based cruise line would have arrived home...

Director of the Pan American Health Organization (PAHO), Carissa Etienne, today urged for vaccination programmes to continue during the COVID-19 pandemic. “If we fall behind on routine immunisations, particularly for children, we risk...

GEORGETOWN, Guyana, CMC – The Guyana government Friday confirmed that US$4.9 million had been deposited into the Natural Resources Fund as a result of the first royalty payment for the country’s crude oil. Finance Minister, Winston...

BRIDGETOWN, Barbados, CMC – A few weeks before the official start of the 2020 Atlantic Hurricane Season, forecasters at the US-based Colorado State University are warning that the six-month period will be more active than normal. The CSU...

BELMOPAN, Belize, CMC – Police Commissioner Chester Williams said there would be “absolutely no room for negotiation” after a family of four, including two minors, were arrested over the last weekend for illegally entering Belize...

ROSEAU, Dominica, CMC –A senior education official Thursday said students would sit the Grade Six National Assessment examinations later this year, despite the disruption caused to the education system by the coronavirus (COVID-19). Dominica...

Glucagon-like peptide 1 (GLP-1) mimetics are effective drugs for treatment of type 2 diabetes, and there is consequently extensive interest in increasing endogenous GLP-1 secretion and L-cell abundance. Here we identify G-protein–coupled bile acid receptor 1 (GPBAR1) as a selective regulator of intestinal L-cell differentiation. Lithocholic acid and the synthetic GPBAR1 agonist, L3740, selectively increased L-cell density in mouse and human intestinal organoids and elevated GLP-1 secretory capacity. L3740 induced expression of Gcg and transcription factors Ngn3 and NeuroD1. L3740 also increased the L-cell number and GLP-1 levels and improved glucose tolerance in vivo. Further mechanistic examination revealed that the effect of L3740 on L cells required intact GLP-1 receptor and serotonin 5-hydroxytryptamine receptor 4 (5-HT4) signaling. Importantly, serotonin signaling through 5-HT4 mimicked the effects of L3740, acting downstream of GLP-1. Thus, GPBAR1 agonists and other powerful GLP-1 secretagogues facilitate L-cell differentiation through a paracrine GLP-1–dependent and serotonin-mediated mechanism.

Reds Spring Training in Goodyear, Ariz., will feature a new manager in David Bell, a new coaching staff and several new players. Here is what you need to know about 2019 camp.

One of the best catchers in baseball was available all winter in J.T. Realmuto, and the Reds were very much one of the teams in hot pursuit in trade talks with the Marlins. But on Thursday, it was the Phillies who acquired Realmuto from Miami.

Though some Reds fans were disappointed that Billy Hamilton wasn't brought back this season, it didn't take long for Cincinnati to find another dynamic player who also brings flash and unpredictability. That would be outfielder Yasiel Puig.

The Reds made their signing of reliever Zach Duke official on Monday, announcing that they've signed the veteran left-hander to a one-year contract.

All 30 Major League teams will wear special "MLB 150" patches on their uniforms for the entire 2019 season in honor of the 150th anniversary of the 1869 Cincinnati Red Stockings, the first openly all-salaried professional baseball team.

It was only five years ago that the Cardinals won the National League Central with only 90 wins. Heck, it was only 12 years ago that the Cubs won it with 85, and 13 that the Cardinals won it with 83. Point is: There have been times in recent baseball history that the NL Central was not exactly the toughest gauntlet in the sport. But in 2019, it looks like the scariest division in baseball.

Reds manager David Bell has great corner outfield depth, but he doesn't have a regular center fielder. Determining who will get to play where and sorting out the log jam should be a challenge for Bell in his first season as a skipper in the big leagues.

Upon the passing of his physical on Tuesday, the Reds signed infielder/outfielder Derek Dietrich to a Minor League contract with an invitation to big league camp for Spring Training.

THE EDITOR, Madam: In times of great challenge and hardship we must continue, as a people, to uphold the values and attitudes that make us truly Jamaican. It is a time for true patriotism and for us to reach down and pull up those among us with...

THE EDITOR, Madam: The Jamaican Government and local private-sector power brokers are still way behind and woefully lacking in investing, financially and otherwise, in Jamaica’s number one most powerful, most famous, most influential, and most...

THE EDITOR, Madam: The right to education, decent work, an adequate standard of living, and housing all fall within the realm of economic, social, and cultural rights (ESCRs) guaranteed under the International Covenant on Economic, Social and...

THE EDITOR, Madam: With most things grinding to a halt worldwide, this pandemic has proven to be as much of an economic crisis as it is a health one. Many sectors have changed their day-to-day operations, with some allowing for greater flexibility...

The COVID-19 pandemic around the world has taken the world by storm, touching the lives of every human being on Earth. The global nature of the crisis has united us as human beings and tragedy and deaths in any country by COVID-19 worry us all....

At the outset, author Ivy Slater shares the existential crisis that spurred her to change careers. Slater’s psychosocial experience after the passing of her father and the stagnation she experienced at her printing business proved exhaustively...

Parish Histories of Jamaica Project, a publication by the JN Foundation in collaboration with the Department of History and Archaeology at The University of the West Indies, Mona, was launched recently. Jenny Jemmott of Department of History and...

Fasting hyperinsulinemia precedes the development of type 2 diabetes. However, it is unclear whether fasting insulin hypersecretion is a primary driver of insulin resistance or a consequence of the progressive increase in fasting glycemia induced by insulin resistance in the prediabetic state. Herein, we have discovered a mechanism that specifically regulates non–glucose-stimulated insulin secretion (NGSIS) in pancreatic islets that is activated by nonesterified free fatty acids, the major fuel used by β-cells during fasting. We show that the mitochondrial permeability transition pore regulator cyclophilin D (CypD) promotes NGSIS, but not glucose-stimulated insulin secretion, by increasing mitochondrial proton leak. Islets from prediabetic obese mice show significantly higher CypD-dependent proton leak and NGSIS compared with lean mice. Proton leak–mediated NGSIS is conserved in human islets and is stimulated by exposure to nonesterified free fatty acids at concentrations observed in obese subjects. Mechanistically, proton leak activates islet NGSIS independently of mitochondrial ATP synthesis but ultimately requires closure of the K_ATP channel. In summary, we have described a novel nonesterified free fatty acid–stimulated pathway that selectively drives pancreatic islet NGSIS, which may be therapeutically exploited as an alternative way to halt fasting hyperinsulinemia and the progression of type 2 diabetes.

Obesity-associated type 2 diabetes mellitus (T2DM) entails insulin resistance and loss of β-cell mass. Adipose tissue mitochondrial dysfunction is emerging as a key component in the etiology of T2DM. Identifying approaches to preserve mitochondrial function, adipose tissue integrity, and β-cell mass during obesity is a major challenge. Mitochondrial ferritin (FtMT) is a mitochondrial matrix protein that chelates iron. We sought to determine whether perturbation of adipocyte mitochondria influences energy metabolism during obesity. We used an adipocyte-specific doxycycline-inducible mouse model of FtMT overexpression (FtMT-Adip mice). During a dietary challenge, FtMT-Adip mice are leaner but exhibit glucose intolerance, low adiponectin levels, increased reactive oxygen species damage, and elevated GDF15 and FGF21 levels, indicating metabolically dysfunctional fat. Paradoxically, despite harboring highly dysfunctional fat, transgenic mice display massive β-cell hyperplasia, reflecting a beneficial mitochondria-induced fat-to-pancreas interorgan signaling axis. This identifies the unique and critical impact that adipocyte mitochondrial dysfunction has on increasing β-cell mass during obesity-related insulin resistance.