👤 Dinesh Kalra

India's escalating burden of obesity and metabolic disease is characterized by a distinctive "thin-fat" phenotype, in which individuals with normal or near-normal body mass index exhibit disproportionate visceral adiposity, reduced skeletal muscle mass, and heightened susceptibility to insulin resistance. Conventional obesity models centered primarily on caloric imbalance fail to adequately explain this pattern, underscoring the need for a more integrative pathophysiological framework. Emerging evidence implicates gut microbiome dysbiosis, impaired fermentation of dietary fibers, reduced short-chain fatty acid (SCFA) signaling, altered bile acid metabolism, metabolic endotoxemia, and dysregulated adipose tissue crosstalk as key contributors to metabolic vulnerability in South Asian populations. This commentary synthesizes mechanistic insights into the gut-metabolic axis and examines their relevance to India's phenotype-specific challenges. Key pathways, including SCFA-mediated incretin secretion, Toll-like receptor 4 (TLR4)-driven inflammatory signaling, angiopoietin-like protein 4 (ANGPTL4)-mediated lipid partitioning, and microbiota-dependent bile acid biotransformation, are discussed as interconnected drivers of metabolic dysfunction. Emerging clinical evidence from randomized controlled trials evaluating synbiotic and prebiotic-botanical formulations is also discussed, highlighting their potential benefits as adjuncts to lifestyle modification. Given India's dietary patterns and widespread deficiency of fermentable fiber intake, synbiotics may represent a scalable and biologically coherent strategy to support metabolic health. However, heterogeneity of formulations, interindividual microbiome variability, and limited long-term outcome data necessitate cautious interpretation. Advancing precision microbiome-targeted interventions will require population-specific research, multi-omics integration, and rigorous clinical evaluation. Show less

Familial hypercholesterolemia (FH) is a common genetic disorder characterized by lifelong elevated low-density lipoprotein cholesterol (LDL-C), leading to a high risk of early onset atherosclerotic cardiovascular disease (ASCVD). This document provides an update to the National Lipid Association's 2011 clinical guidance, summarizing the remarkable progress in the field. With a global prevalence of approximately 1 in 311, FH remains severely underdiagnosed. This guidance reviews current diagnostic criteria, including the expanding role of genetic testing to complement diagnosis and to facilitate cascade screening, and emphasizes a thorough differential diagnosis. It provides recommendations for universal pediatric screening and systematic cascade screening in families to improve detection. Management strategies include intensified LDL-C treatment goals for both primary and secondary prevention of ASCVD. A stepwise approach to optimal therapy is outlined, beginning with lifestyle interventions and pharmacotherapy with maximally tolerated statins and ezetimibe. This update incorporates newer agents, including proprotein convertase subtilisin/kexin type 9 inhibitors and bempedoic acid. Additional therapies, such as lomitapide and evinacumab for homozygous FH and lipoprotein apheresis for heterozygous and homozygous FH, are discussed. Further topics include cardiovascular imaging for risk stratification, management in specific populations and circumstances, such as planning for and during pregnancy and in pediatrics, and recognition of health disparities. This guidance equips clinicians with evidence-based strategies to improve the identification and care of patients with FH, ultimately reducing the high morbidity and mortality associated with this condition. Show less

APOE4 is a risk factor for several disease states associated with cognitive impairment, including Alzheimer's disease and cancer-chemotherapy induced cognitive impairment. Using mouse knock-in models of human APOE alleles, we examined the effects of APOE genotype and chemotherapy on the ex vivo electrophysiological characteristics of excitatory and inhibitory neurons in the entorhinal cortex (EC). We found that APOE4 is associated with a significantly higher excitatory/inhibitory ratio (0.33 ± 0.04) in the layer 2/3 pyramidal cells of the entorhinal cortex compared to APOE3 (0.19 ± 0.04). We crossed APOE mice to mice with parvalbumin (PV) interneurons tagged with tdTomato, allowing us to measure effects specifically on this inhibitory cell type. For EC pyramidal neurons, the chemotherapeutic agent doxorubicin caused increases in the amplitudes of both spontaneous excitatory and inhibitory post-synaptic currents, with significant responses (***p < 0.001; **p < 0.01 respectively) in APOE3 brains. For EC PV neurons, APOE4 genotype was associated with significantly lower firing rates at injections of high currents (**p < 0.01), but rates were unaffected by doxorubicin. Doxorubicin doubled the percentage of PV cells that showed inactivation block in APOE3 brains (25% to 52%) but had no effect on APOE4 brains (50% to 54%). This ex vivo study suggests that APOE4 impairs homeostatic synaptic transmission in pyramidal cells under control conditions and causes a lack of responsiveness to a stressor (doxorubicin treatment) in PV cells. Show less

Obesity is a heterogeneous, complex, and chronic disease that has a detrimental impact on disability-adjusted life years across the globe. Recent advancements in our understanding of gut-brain communication at the molecular level have driven the development of next-generation anti-obesity medications (AOMs). Glucagon-like peptide-1 receptor agonists (GLP1RAs) remain the front-runners in this rapidly evolving landscape of hormone-based AOMs. Two GLP1RAs, namely Liraglutide and Semaglutide, have been approved by the Food and Drug Administration (FDA) and European Medicine Agency (EMA) for use in clinical practice for weight loss. Three oral GLP1RAs, namely Semaglutide, Danuglipron, and Orforglipron, are undergoing advanced clinical trials in individuals with obesity. Amylin receptor agonist (AMYRA) Cagrilintide, when used alone or in combination with Semaglutide, has demonstrated substantial weight reduction in clinical trials. Tirzepatide, a dual agonist for the glucose-dependent insulinotropic polypeptide (GIP) and GLP-1 receptors, has been observed to be associated with a significant placebo-subtracted weight reduction of 17.8% in a 72-week randomized controlled trial. Novel approaches targeting glucagon signalling have also yielded promising preliminary results. Three long-acting GLP1R/glucagon receptor (GCGR) dual agonists, namely Survodutide, Mazdutide, and Pemvidutide, exhibited significant weight loss in clinical trials. Retatrutide, a GLP1R/GCGR/GIPR tri-agonist, has been associated with a placebo-subtracted weight reduction of -22.1% in a 48-week phase-II trial. As a note of caution, long-term data on such medications' safety and cardiovascular benefits is yet to be ascertained. Our review provides a comprehensive overview of the approved and emerging hormone-based AOMs, highlighting the diversity of options that might become available in the near future. Show less

Hypertrophic cardiomyopathy (HCM) is a common but an underdiagnosed condition. Fasciculoventricular bypass tract (FVBT) is rare. Concomitant presence of both conditions is well described in Danon disease. We report a case of familial HCM with FVBT linked to a heterozygous pathogenic variant, c.655G>C (p.Val219Leu), in the cardiac myosin binding protein C3 (MYBPC3) gene. ( Show less