👤 Daniel Smith

Gastrointestinal (GI) enterochromaffin (EC) cells are specialised sensors of luminal stimuli. They secrete most of the body's serotonin (5-HT), and are critical for modulating GI motility, secretion, and sensation, while also signaling satiety and intestinal discomfort. The aim of this study was to investigate mechanisms underlying the regulation of human EC cells, and the relative importance of direct nutrient stimulation compared with neuronal and paracrine regulation. Intestinal organoids from human duodenal biopsies were modified using CRISPR-Cas9 to specifically label EC cells with either the fluorescent protein Venus or the cyclic adenosine monophosphate (cAMP) sensor Epac1-S-H187. EC cells were purified by fluorescence-activated cell sorting for analysis by bulk RNA sequencing and liquid chromatography mass spectrometry peptidomics. The function of human EC cells was studied using single-cell patch clamp, calcium and cAMP imaging, and 5-hydroxytryptamine (5-HT) enzyme-linked immunosorbent assays (ELISAs). Human EC cells showed expression of receptors for nutrients (including GPR142, GPBAR1, GPR119, FFAR2, OR51E1, OR51E2), gut hormones (including SSTR1,2&5, NPY1R, GIPR) and neurotransmitters (ADRA2A, ADRB1). Functional assays revealed EC responses (calcium, cAMP, and/or secretion) to a range of stimuli, including bacterial metabolites, aromatic amino acids, and adrenergic agonists. Electrophysiological recordings showed that isovalerate increased action potential firing. 5-HT release from EC cells controls many physiological functions and is currently being targeted to treat disorders of the gut-brain axis. Studying ECs from human organoids enables improved understanding of the molecular mechanisms underlying EC cell activation, which is fundamental for the development of new strategies to target 5-HT-related gut and metabolic disorders. Show less

Obesity causes dyslipidemia and is a major risk factor for cardiovascular disease. However, the mechanisms coupling weight gain and lipid metabolism are poorly understood. Brain melanocortin 4 receptors (MC4Rs) regulate body weight and lipid metabolism in mice, but the relevance of these findings to humans is unclear. Here we investigated lipid levels in men and women with obesity due to MC4R deficiency. Among 7,719 people from the Genetics of Obesity Study cohort, we identified 316 probands and 144 adult family members with loss-of-function (LoF) MC4R mutations. Adults with MC4R deficiency had lower levels of total and low-density lipoprotein (LDL)-cholesterol and triglycerides than 336,728 controls from the UK Biobank, after adjusting for adiposity. Carriers of LoF MC4R variants within the UK Biobank had lower lipid levels and a lower risk of cardiovascular disease, after accounting for body weight, compared to noncarriers. After a high-fat meal, the postprandial rise in triglyceride-rich lipoproteins and metabolomic markers of fatty acid oxidation were reduced in people with MC4R deficiency compared to controls, changes that favor triglyceride storage in adipose tissue. We concluded that central MC4Rs regulate lipid metabolism and cardiovascular disease risk in humans, highlighting potential therapeutic approaches for cardiovascular risk reduction. Show less

The preoptic area (POA) is a well-established regulator of body temperature, but its role in feeding behavior remains underexplored. Our study identifies leptin receptor (Lepr)-expressing neurons in the POA (POA Show less

We tested whether genetically proxied non-high-density lipoprotein cholesterol (non-HDL-C)-lowering drug targets reduce risk of all-cause dementia. We included 1,091,775 individuals from three prospective general population cohorts with individual-level data and two consortia with summary-level data. We selected genetic variants within HMGCR, NPC1L1, PCSK9, ANGPTL4, LPL, and CETP associated with non-HDL-C. These variants were used as exposures in Cox regression and one- and two-sample Mendelian randomization. Results were meta-analyzed. Meta-analysis of one-sample Mendelian randomization odds ratios per 1 mmol/L (39 mg/dL) lower non-HDL-C was 0.24 (0.18-0.31) for HMGCR, 0.18 (0.12-0.25) for NPC1L1, 0.97 (0.70-1.35) for PCSK9, 1.66 (0.52-5.36) for ANGPTL4, 1.41 (0.63-3.16) for LPL, and 0.30 (0.26-0.34) for CETP. Cox regression and two-sample Mendelian randomization results were mostly directionally consistent. Genetic lowering of non-HDL cholesterol via HMGCR, NPC1L1, and CETP reduces the risk of dementia. This reflects the effect of lifelong differences in non-HDL cholesterol on risk of dementia. Variants in HMGCR, NPC1L1, and CETP reduce the risk of dementia via non-high-density lipoprotein cholesterol (non-HDL-C). An effect of PCSK9, ANGPTL4, and LPL variants on dementia risk cannot be excluded. This reflects the effect of lifelong lower non-HDL-C on risk of dementia. Show less

The role of lipid-perturbing medications in cancer risk is unclear. We employed cis-Mendelian randomization and colocalization to evaluate the role of 5 lipid-perturbing drug targets (ANGPTL3, ANGPTL4, APOC3, CETP, and PCSK9) in risk of 5 cancers (breast, colorectal, head and neck, ovarian, and prostate). We triangulated findings using pre-diagnostic protein measures in prospective analyses in EPIC (977 colorectal cancer cases, 4080 sub-cohort members) and the UK Biobank (860 colorectal cancer cases, 50 177 controls). To gain mechanistic insight into the role of ANGPTL4 in carcinogenesis, we examined the impact of the ANGPTL4 p. E40K loss-of-function variant on differential gene expression in normal colon tissue in BarcUVa-Seq. Finally, we evaluated the association of colon tumor ANGPTL4 expression with cancer-specific mortality in TCGA. In analysis of 78 473 cases and 107 143 controls, genetically proxied circulating ANGPTL4 inhibition was associated with reduced colorectal cancer risk (ORSD decrease = 0.76, 95% confidence interval [CI] = 0.66 to 0.89, P = 5.52 × 10-4, PPcolocalization = 0.83). This association was replicated using pre-diagnostic circulating ANGPTL4 concentrations in EPIC (hazard ratio [HR]log10 decrease = 0.91, 95% CI = 0.84 to 0.98, P = .01) and the UK Biobank (HRSD decrease = 0.93, 95% CI = 0.86 to 0.99, P = .03). In gene-set enrichment analysis of differential gene expression in 445 colon tissue samples, ANGPTL4 loss-of-function down-regulated several cancer-related biological pathways (PFDR < .05), including those involved in cellular proliferation, epithelial-to-mesenchymal transition, and bile acid metabolism. In analysis of 465 colon cancer patients, lower ANGPTL4 tumor expression was associated with reduced colorectal cancer-specific mortality risk (HRlog2 decrease = 0.66, 95% CI = 0.50 to 0.87, P = 2.92 × 10-3). Our integrative proteogenomic and observational analyses suggest a potential protective role of lower circulating ANGPTL4 concentrations in colorectal cancer risk. These findings support further evaluation of ANGPTL4 as a therapeutic target for colorectal cancer prevention. Show less

The liver plays essential roles in maintaining systemic glucolipid homeostasis under ever changing metabolic stressors. Metabolic dysregulation can lead to both adaptive and maladaptive changes that impact systemic physiology. Here, we examined disparate genetic and environmental metabolic stressors and identified apolipoprotein A4 (ApoA4) as a circulating protein upregulated in liver-specific KOs for carnitine palmitoyltransferase 2 and pyruvate carboxylase. We found this upregulation to be exacerbated by fasting and high-fat or ketogenic diets. Unique among these models was a concomitant increase in activating transcription factor 3 (Atf3). Liver-specific overexpression of Atf3 resulted in increased ApoA4 expression in a sex-dependent manner. To understand the requirement of Atf3 to metabolic stress, we generated liver-specific Atf3, Cpt2 double KO mice. These experiments demonstrated the requirement for Atf3 in the induction of ApoA4 mRNA, ApoA4 protein, and serum triglycerides that were also sex-dependent. These experiments reveal the roles of hepatic Atf3 and ApoA4 in response to metabolic stress in vivo. Show less

Cholesteryl ester transfer protein (CETP) mediates the exchange of triglycerides (TG) from apolipoprotein B (ApoB)-containing lipoproteins to high-density lipoproteins (HDL) and the reciprocal exchange of cholesterol (C) from HDL to ApoB-containing lipoproteins. CETP inhibition increases HDL-C and decreases low-density lipoprotein cholesterol (LDL-C) while modestly decreasing TG. Considering that CETP inhibitors block removal of TG from TG-rich lipoproteins (TRL), it is interesting that CETP inhibition decreases TG concentrations. TG levels are largely regulated by lipoprotein lipase (LPL), the enzyme primarily responsible for hydrolyzing TG. The angiopoietin-like 3/8 complex (ANGPTL3/8) is the most potent circulating LPL inhibitor, while the TG-lowering apolipoprotein A5 (ApoA5) acts by suppressing ANGPTL3/8-mediated LPL inhibition. To better understand CETP biology, we studied the effects of CETP overexpression and CETP inhibition on the levels of ANGPTL3/8 and ApoA5 in circulation using dedicated immunoassays. CETP-overexpressing transgenic mice had increased TG and normal ANGPTL3/8 levels but manifested dramatically reduced ApoA5 concentrations. Administration of the CETP inhibitor evacetrapib had no effect on ANGPTL3/8 levels in CETP-overexpressing mice or in humans. However, evacetrapib administration increased ApoA5 concentrations in both species. In human subjects, evacetrapib treatment increased circulating ApoA5 levels in the late-stage ACCELERATE and ACCENTUATE studies by 160.1% and 204.7%, respectively. Our results uncover a previously unrecognized link between CETP and ApoA5 by showing that CETP overexpression reduces ApoA5 levels while CETP inhibition increases ApoA5 concentrations. Show less

Adverse drug responses (ADRs) result in over 7,000 deaths annually. Pharmacogenomic studies have shown that many ADRs are partially attributable to genetics. However, emerging data suggest that epigenetic mechanisms, such as DNA methylation (DNAm) also contribute to this variance. Understanding the impact of DNA methylation on drug response may minimize ADRs and improve the personalization of drug regimens. In this work, we identify DNA methylation sites that likely impact drug response phenotypes for anticoagulant and cardiometabolic drugs. We use instrumental variable analysis to integrate genome-wide association study (GWAS) summary statistics derived from electronic health records (EHRs) within the U.K. Biobank (UKBB) with methylation quantitative trait loci (mQTL) data from the Genetics of DNA Methylation Consortium (GoDMC). This approach allows us to achieve a robust sample size using the largest publicly available pharmacogenomic GWAS. For warfarin, we find 71 DNAm sites. Of those, 8 are near the gene VKORC1 and 48 are on chromosome 6 near the human leukocyte antigen (HLA) gene family. We also find 2 warfarin DNAm sites near the genes CYP2C9 and CYP2C19. For statins, we identify 17 DNAm sites. Eight are near the APOB gene, which encodes a carrier protein for low-density lipoprotein cholesterol (LDL-C). We find no novel significant epigenetic results for metformin. Show less

Alzheimer's disease and related dementias (ADRD) are major public health concerns. DNA methylation (DNAm)-based biomarkers such as GrimAge and PhenoAge predict aging and health risk, but were not designed to optimize prediction of cognitive decline. We used data from the 2016 Venous Blood Study of the Health and Retirement Study (HRS), a nationally representative cohort of U.S. adults aged ≥51 years (N = 3575 with high-quality DNAm). Epigenetic g scores were computed using CpG weights from a BayesR+ model of general cognitive ability developed in Generation Scotland. Cognitive function was measured with a modified version of the Telephone Interview for Cognitive Status (TICS) at each interview wave; 6-year incident dementia was defined using the validated Langa-Weir algorithm. Linear regression estimated associations with cognitive scores; logistic regression estimated 4-year dementia risk. Models were adjusted sequentially for demographics, education, parental education, APOE ε4 status, and blood-based neurodegeneration markers (NfL, GFAP, Aβ42/40, pTau181). Higher epigenetic g was associated with better baseline cognition (β=2.55, 95% CI 1.92-3.17) and cognition at the time DNAm was measured (β=2.30, 95% CI 1.62-2.99) after demographic adjustment. Associations attenuated but remained significant with education and parental education (β=1.23-1.89). Each unit increase in epigenetic g predicted 29% lower 6-year risk of dementia (fully adjusted HR=0.71). Results were robust to adjustment for APOE ε4 and neurodegeneration biomarkers. Epigenetic g is a scalable, blood-based marker of cognitive function and dementia risk that adds predictive value beyond demographics, socioeconomic indicators, APOE, and neuropathology. Its validation in a diverse, nationally representative U.S. cohort underscores its potential for early risk profiling and for research on social determinants of cognitive aging in cross-national samples. Show less

Alzheimer's disease (AD) pathology is complex and involves mitochondrial dysfunction. There are emerging therapies targeting mitochondrial function in clinical trials for AD. This highlights the need for biomarkers that measure mitochondrial function. We determined the utility of a novel blood-based mitochondrial biomarker, the mitochondrial functional index (MFI), in the context of AD in a pilot study. In vitro and in vivo models of AD had a reduced MFI. MFI was lower in human AD subjects and APOE 𝜀4 carriers. Receiver operating characteristic analysis showed MFI had a higher area under the curve than other plasma biomarkers. The MFI biomarker correlated with the Mini-Mental State Examination (MMSE) and the Clinical Dementia Rating (CDR) scale. This study highlights the potential utility of MFI as a functional blood-based mitochondrial biomarker to interrogate energy metabolism. Ongoing studies are examining the relationship of MFI with brain energy metabolism outcomes. The MFI biomarker is reduced in cell and animal models of AD. The MFI biomarker is reduced in human AD subjects and APOE ε4 carriers. The MFI biomarker can discriminate between subjects with normal cognition and AD with better performance than other plasma biomarkers. The MFI biomarker correlates with cognitive scores. Show less

Overexpression of the low-density lipoprotein receptor (LDLR) is known to decrease apolipoprotein E (APOE) levels and alleviate amyloid beta (Aβ) pathology. We hypothesized that inhibiting the Inducible Degrader of LDLR (IDOL), an enzyme that ubiquitinates LDLR for degradation, would increase endogenous LDLR levels and attenuate amyloid pathology. To investigate the cell-type-specific role of IDOL, we generated Idol conditional knockout mice on an Aβ-amyloidosis mouse model and performed biochemical, histological, and multi-omics analyses. We demonstrated that neuronal, but not microglial, Idol deletion reduced amyloid accumulation and altered brain LDLR and APOE levels, indicating the critical role of neuronal IDOL-LDLR in amyloid pathology. In addition, neuronal Idol deletion increased the levels of Reelin receptors important for synaptic function, and single-nuclei RNA sequencing revealed significant changes associated with synaptic organization. Neuronal IDOL, but not microglial IDOL, plays a key role in Alzheimer's disease pathogenesis by regulating the levels of brain APOE receptors. Neuronal, but not microglial, Idol deletion reduces amyloid burden and modulates brain APOE and LDLR levels. Deletion of neuronal Idol increases the levels of APOER2 and VLDLR, the Reelin receptors, in the brain. Single-nuclei RNA sequencing highlights the neuronal IDOL's impact on inhibitory neurons and synaptic organization. Targeting neuronal IDOL may provide multiple therapeutic benefits in Alzheimer's disease by modulating APOE receptors. Show less

Alzheimer's disease (AD) is a progressive neurodegenerative disorder associated with impairments in memory and executive functions. Despite significant advancements in identifying genetic risk factors, the high cost and limited accessibility of genetic testing remain major barriers. In this work, we propose a cost-effective screening approach that leverages EEG recordings and psychometric test scores to predict an individual's genetic risk for AD. Our Convolutional Neural Network (CNN) model shows promising performance: it achieved an F1 score of 72.21% in distinguishing APOE-ϵ4/PICALM GG non-carriers (N) from APOE-ϵ4 carriers with the risky PICALM GG alleles (A+P+). It reached an F1 score of 60.78% for differentiating non-carriers (N) from APOE-ϵ4 carriers without the risky alleles (A+P-), and 65.12% when separating A+P- from A+P+. To enhance interpretability, we employ Grad-CAM, which reveals that EEG features contribute more significantly to gene prediction than psychometric measures. Notably, our model also identifies three key psychometric tests, MINI COPE (which assesses emotional coping skills), the California Verbal Learning Test (CVLT), and NEO Neuroticism, as associated with higher AD risk, consistent with prior research. Moreover, our results align with earlier findings reporting increased theta-band power among high-risk individuals. Finally, Higuchi Fractal Dimension (HFD) features drove most of the EEG-based prediction capability, as shown through our ablation study. This study highlights the potential of integrating neurophysiological and cognitive assessments to develop accessible and reliable screening tools for AD genetic risk, enabling earlier diagnoses. The code has been released at https://github.com/ Shyamal-Dharia/EEG-Psycho-Genes-AD. Show less

Lipid profiles are largely determined by genetic variants, and lipid metabolism plays a crucial role in Alzheimer's disease. To investigate whether lipid profile variability in response to diverse statins could be affected by cholesterol metabolism-related genetic variants in Alzheimer's disease.. This prospective observational pharmacogenetic study was conducted at the Universidade Federal de São Paulo (Unifesp), Brazil. Consecutive outpatients were prospectively followed for lipid profile variations over one year, estimated by the associations between statin therapy and the following variants: rs2695121 (NR1H2), rs3846662 (HMGCR), rs11669576 (LDLR8), rs5930 (LDLR10), rs5882 and rs708272 (CETP), rs7412 and rs429358 (APOE), and ACE insertion/deletion polymorphism. All polymorphisms in the 189 patients were in Hardy-Weinberg equilibrium. Statins resulted in lower total cholesterol and LDL cholesterol levels, whereas the effects on HDL cholesterol varied according to the statin used. Atorvastatin resulted in lower triglyceride level variations than simvastatin. APOE-ε4 carriers showed a better response to atorvastatin in elevating HDL-cholesterol than APOE-ε4 non-carriers. Carriers of the ACE insertion allele had cumulatively lower total cholesterol and LDL-cholesterol levels, regardless of statin therapy, but lower triglyceride levels when using atorvastatin. Carriers of rs11669576-G had lower total cholesterol and LDL-cholesterol levels when using simvastatin, and lower total cholesterol and triglycerides when using atorvastatin. Concerning CETP haplotypes, carriers of rs5882-A and rs708272-A benefitted the most from statins, which lowered total cholesterol and increased HDL-cholesterol levels, and from atorvastatin lowering triglycerides; however, the effects of atorvastatin lowering total cholesterol and LDL-cholesterol were more pronounced for carriers of rs5882-GG/rs708272-GG. Lipid profile variations may be pharmacogenetically mediated in Alzheimer's disease, thus, confirming their high heritability. Show less

CLN3 disease is a rare fatal juvenile neurodegenerative lysosomal storage disease. Challenges in tracking underlying disease biology have hindered the identification of effective therapeutic targets and the ability to execute clinical trials in this rare disease. While diagnostic biomarkers are readily available, biomarkers that reflect the underlying core lysosome dysfunction are lacking. In the present study, CLN3 Show less

Growth factor induced receptor dimerization and activation of downstream pathways can modulate cell fate decisions. Here, we investigate the potential of de novo designed synthetic ligands, termed Novokines, to reprogram cell identity by inducing proximity of novel pairs of receptor subunits. We find that a design, H2F, that brings together HER2 (which has no known natural ligand) and the FGF receptor has potent signaling activity. H2F induces robust signaling and reprograms fibroblasts into myogenic cells. Unlike native FGF ligands, H2F selectively activates the MAPK pathway without engaging PLCγ-mediated Ca²⁺ signaling. FRET assays confirm H2F-mediated HER2-FGFR proximity, and phosphoproteomic analysis reveals activation of MAPK effectors. H2F-induced ERK phosphorylation is abolished in cells expressing a kinase-dead FGFR1 (K514M) mutant, confirming the requirement for FGFR catalytic activity. H2F treatment significantly increases myofiber formation from adult patient-derived primary myoblasts, demonstrating its capacity to promote myogenic regeneration. Our findings demonstrate that synthetic receptor pairings can rewire signaling outputs to drive regeneration, providing a programmable platform for cell fate engineering. Show less

Oncogenic alterations in fibroblast growth factor receptor (FGFR)-family proteins occur across cancers, including pediatric gliomas. Our genomic analysis of 11,635 gliomas across ages finds that 5.3% of all gliomas harbor FGFR alterations, with an incidence of almost 9% in pediatric gliomas. Alterations in FGFR proteins are differentially enriched by age, tumor grade, and histology, with FGFR1 alterations associated with glioneuronal histologies. Leveraging isogenic systems, we confirm FGFR1 alterations to induce downstream Mitogen Activated Protein Kinase (MAPK) and mTOR signaling pathways, drive gliomagenesis, activate neuronal transcriptional programs and exhibit sensitivity to MAPK pathway and pan-FGFR inhibitors. Finally, we perform a retrospective analysis of clinical responses in children diagnosed with FGFR-altered gliomas and find that treatment with currently available inhibitors is largely associated with stability of disease. This study provides key insights into the biology of FGFR1-altered gliomas, therapeutic strategies to target them and associated challenges that still need to be overcome. Show less

Recent studies have highlighted the deleterious role of high phosphate intake in hypertension via sympathetic overactivation, yet the underlying mechanisms remain unclear. Dietary phosphate loading triggers physiologic release of FGF23 (fibroblast growth factor-23) from the bone to maintain phosphate homeostasis. Both FGF23 and FGF receptors (FGFRs) are present in the central nervous system, but their role in neural control of blood pressure during phosphate loading is unknown. We investigated central FGF23/FGFR signaling in high-phosphate diet-induced sympathetic dysregulation of blood pressure in rats. FGF23 protein levels were measured by immunoprecipitation, immunoblotting, and immunohistochemistry. FGF23 translocation into the brain was determined by injecting infrared-labeled FGF23 intravenously into anesthetized Sprague-Dawley rats. Mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA) responses to hindlimb muscle contraction were measured in decerebrate Sprague-Dawley rats treated with either a normal 0.6% phosphate diet (NP) or a high 1.2% phosphate diet (HP) for 12 weeks before and after intracerebroventricular (ICV) administration of FGFR signaling inhibitors. Excess phosphate intake significantly increased FGF23 protein levels in the brainstem (HP versus NP, Our data reveal a novel pathophysiologic paradigm of high-phosphate diet-induced sympathoexcitation and hypertension by FGF23 crossing into the brain, possibly acting via FGFR4. Show less

Historically, 17β-hydroxysteroid dehydrogenase type 3 (HSD17B3) was thought to be the key enzyme responsible for testicular testosterone production. In humans, loss-of-function mutations in HSD17B3 impair testosterone production during prenatal life leading to impaired development of androgen-dependent tissues in 46,XY individuals. However, male mice with HSD17B3 deficiency exhibit normal testicular testosterone concentrations, normal development of reproductive organs and are fertile, suggesting that mice express other hydroxysteroid dehydrogenase enzymes capable of testicular testosterone synthesis. This study aimed to investigate whether 17β-hydroxysteroid dehydrogenase type 12 (HSD17B12), which can convert androstenedione to testosterone in mice but not in humans, compensates for the lack of HSD17B3 in Hsd17b3 knockout (KO) mice. We used CRISPR/Cas9 to substitute the amino acid in mouse HSD17B12 that is responsible for its ability to convert androstenedione to testosterone with the amino acid of the human enzyme that prevents androstenedione being used as a substrate. When this Hsd17b12 mutation was introduced into Hsd17b3 KO mice, males exhibited normal reproductive tracts but reduced testicular testosterone production with a consequential reduction in seminal vesicle weight. This suggests HSD17B12 contributes toward testosterone production in the absence of HSD17B3, but other enzymes must also contribute. We therefore quantified other testicular hydroxysteroid dehydrogenases, finding that HSD17B7 mRNA and protein was markedly upregulated in Hsd17b3 KO testes. We confirmed that mouse, but not human, HSD17B7 can produce testosterone in vitro. We conclude that compared to humans, mice exhibit increased plasticity in testosterone production via hydroxysteroid dehydrogenase enzymes to support androgen action and male fertility. Show less

Previous reports of distal deletions in chromosome 10q in patients have described distinct facial features combined with other neurodevelopmental abnormalities, including intellectual disability. However, the association of interstitial deletions in chromosome 10q with global developmental delay, musculoskeletal abnormalities, and dysmorphic features has not been previously reported. Genetic testing using whole exome sequencing (WES) was performed on three patients with neurodevelopmental delay, musculoskeletal abnormalities and dysmorphic features. Sequencing reads were aligned to the human genome build GRCh37/UCSC hg19 and analysed for both sequence and copy number variants. WES identified similar interstitial deletions in the 10q21.1q21.3 locus in all three patients. The deleted region includes online Mendelian inheritance in man (OMIM)-annotated genes with clinical significance, such as This is the first report associating interstitial deletions in the 10q21.1q21.3 locus with neurodevelopmental delay, musculoskeletal abnormalities and dysmorphic features. Our findings highlight the clinical significance of this deleted region and suggest possible mechanisms underlying the observed pathological phenotypes. Show less

Lipoprotein(a) [Lp(a)] is increasingly recognized as a genetically determined, independent risk factor for atherosclerotic cardiovascular disease (ASCVD). This review examines the structure, pathophysiology, and epidemiology of Lp(a), with a focus on its contribution to ASCVD and related conditions such as aortic valve stenosis and peripheral artery disease. The main research question addresses how Lp(a) influences cardiovascular risk and how emerging therapies may modify this risk. This review synthesizes published evidence describing the biological characteristics of Lp(a), its mechanistic roles in disease, and its epidemiologic associations with cardiovascular outcomes. It also evaluates current and investigational therapeutic approaches by examining clinical trial data for agents targeting Lp(a). Lp(a) contributes to residual cardiovascular risk through proatherogenic, proinflammatory, and prothrombotic mechanisms. Current evidence highlights its involvement in ASCVD, aortic valve stenosis, and peripheral artery disease. Clinical studies of antisense oligonucleotides, small interfering RNAs, oral small molecules, and CRISPR-based gene editing, including pelacarsen, olpasiran, zerlasiran, lepodisiran, muvalaplin, and obicetrapib, demonstrate promising efficacy and safety. These agents show potential to significantly reduce Lp(a) levels and influence future cardiovascular prevention strategies. As novel therapies advance and clinical guidelines evolve, Lp(a) is emerging as a central determinant in personalized cardiovascular care. The increasing emphasis on Lp(a) testing underscores its importance in risk stratification and future therapeutic decisionmaking. Show less

The purpose of this population-based study was to examine whether sedentary behavior (SB) and light physical activity intensity (LPA) are associated with pain in older adults. A further aim is to investigate the psychosomatic complaints as mediators between SB and pain. Individuals aged ≥50 from the 2018 Study on Aging, Health, and Health-seeking Behavior reported on SB and LPA using the International Physical Activity Questionnaire and pain severity using a cross-culturally validated item from the bodily pain subscale of the MOS SF-36. Multivariable logistic regression models evaluated the associations of SB and LPA with pain. Bootstrapping analyses assessed whether psychosomatic complaints mediate the association between SB and pain. Among 1201 participants (mean ± SD age = 66.1 ± 11.9 years; women = 63.3%), the prevalence of SB and pain was 21.4% and 43.0%, respectively. Compared with <8 h/d, ≥8 h/d of SB was positively associated with pain (OR = 2.42, 95% CI = 1.71-3.42). However, LPA was associated with 11% lower odds of reporting pain (OR = 0.89, 95% CI = 0.81-0.98). Self-rated health (41.2%), anxiety (23.5%), comorbidity (20.6%), functional limitations (17.6%), depression (13.2%), and sleep problems (11.8%) were associated with pain and mediated the SB-pain link. The present study observed that SB and LPA were associated with pain in older adults residing in Ghana, and psychosomatic complaints were identified as potential mechanisms in the pathway between SB and pain. Managing the pain burden in old age may require shifting the 24-hour behavior from SB to LPA and addressing the inherent psychosomatic complaints. Show less

Suicidal ideation and attempts as well as eating disorders (EDs) are common among Iranian individuals. Additionally, ED symptoms are associated with suicidality. According to the interpersonal-psychological theory of suicide (IPTS), factors such as thwarted belongingness, perceived burdensomeness, and capability for suicide must combine for suicidality to occur. The tenets of IPTS have been supported among individuals with ED symptoms from Western countries. However, no study has yet explored how ED symptoms might co-occur with IPTS factors and potentially relate to suicidal ideation and attempts using latent profile analysis (LPA). Participants (N = 773) were Iranian community members who completed a battery of scales assessing ED symptoms, suicide-related risk factors, as well as suicidal ideation and suicide attempts. The LPA revealed that a six-class solution best fit the data. The classes with the highest levels of IPTS and binge/purge related symptoms also had the highest odds of suicide attempts. Our findings suggest that the measurement of thwarted belongingness, perceived burdensomeness, and capability for suicide is particularly important for individuals with binge/purge type eating disorder symptoms. Overall, IPTS factors should be incorporated into assessments of clients presenting with ED symptoms and suicidality. Show less

Severe hypertriglyceridemia causing acute pancreatitis may necessitate intensive care unit (ICU) admission. Management of hypertriglyceridemia in this setting requires therapies that result in rapid triglyceride lowering that are different from therapies used in the outpatient setting. The purpose of this narrative review is to explore strategies for managing hypertriglyceridemia-induced acute pancreatitis (HTGP) in the ICU. Patients may develop acute pancreatitis when triglyceride levels exceed 500 mg/dL, either as their primary reason for admission to the ICU or as an adverse effect of medications received during ICU care. Rapid reduction of triglycerides is attained through activation of lipoprotein lipase (LPL), an enzyme essential for the removal of triglycerides from the plasma. Treatment modalities include therapeutic plasma exchange and the combination of insulin and heparin infusions for acute treatment, although there is no consensus on optimal dosing. Fibrates are recommended as first-line agents in prevention of hypertriglyceridemia-induced pancreatitis in high-risk patients. Several therapies are used for acute management of HTGP in the ICU setting. Further research is necessary to refine treatment protocols and establish best practices for managing HTGP in critically ill patients. Show less

Angiopoietin-like 3 (ANGPTL3) is a major regulator of lipoprotein metabolism. ANGPTL3 deficiency results in lower levels of triglycerides, LDL-cholesterol (LDL-C), and HDL-cholesterol (HDL-C), and may protect from cardiovascular disease. ANGPTL3 oligomerizes with ANGPTL8 to inhibit lipoprotein lipase (LPL), the enzyme responsible for plasma triglyceride hydrolysis. Independently of ANGPTL8, oligomers of ANGPTL3 can inhibit endothelial lipase (EL), which regulates circulating HDL-C and LDL-C levels through the hydrolysis of lipoprotein phospholipids. The N-terminal region of ANGPTL3 is necessary for both oligomerization and lipase inhibition. However, our understanding of the specific residues that contribute to these functions is incomplete. In this study, we performed mutagenesis of the N-terminal region to identify residues important for EL inhibition and oligomerization. We also assessed the presence of different ANGPTL3 species in human plasma. We identified a motif important for lipase inhibition, and protein structure prediction suggested that this region interacted directly with EL. We also found that recombinant ANGPTL3 formed a homotrimer and was unable to inhibit EL activity when trimerization was disrupted. Surprisingly, we observed that human plasma contained more monomeric ANGPTL3 than trimeric ANGPTL3. An important implication of these findings is that previous correlations between circulating ANGPTL3 and circulating triglyceride-rich lipoproteins need to be revisited. Show less

To delineate organ-specific and systemic drivers of metabolic dysfunction-associated steatotic liver disease (MASLD), we applied integrative causal inference across clinical, imaging, and proteomic domains in individuals with and without type 2 diabetes (T2D). We used Bayesian network analyses to quantify causal pathways linking adipose distribution, glycemia, and insulin dynamics with fatty liver using data from the IMI-DIRECT prospective cohort study. Measurements were made of glucose and insulin dynamics (using frequently-sampled metabolic challenge tests), MRI-derived abdominal and liver fat content, serological biomarkers, and Olink plasma proteomics from 331 adults with new-onset T2D and 964 adults free from diabetes at enrolment. The common protocols used in these two cohorts provided the opportunity for replication analyses to be performed. When the direction of the effect could not be determined with high probability through Bayesian networks, complementary two-sample Mendelian randomization (MR) was employed. High basal insulin secretion rate (BasalISR) was identified as the primary causal driver of liver fat accumulation in both diabetes and non-diabetes. Excess visceral adipose tissue (VAT) was bidirectionally associated with liver fat, indicating a self-reinforcing metabolic loop. Basal insulin clearance (Clinsb) worsened as a consequence of liver fat accumulation to a greater degree before the onset of T2D. Out of 446 analysed proteins, 34 mapped to these metabolic networks and 27 were identified in the non-diabetes network, 18 in the diabetes network, and 11 were common between the two networks. Key proteins directly associated with liver fat included GUSB, ALDH1A1, LPL, IGFBP1/2, CTSD, HMOX1, FGF21, AGRP, and ACE2. Sex-stratified analyses revealed distinct proteomic drivers: GUSB and LEP were most predictive of liver fat in females and males, respectively. Basal insulin hypersecretion is a modifiable, causal driver of MASLD, particularly prior to glycaemic decompensation. Our findings highlight a multifactorial, sex- and disease-stage-specific proteo-metabolic architecture of hepatic steatosis. Proteins such as GUSB, ALDH1A1, LPL, and IGFBPs warrant further investigation as potential biomarkers or therapeutic targets for MASLD prevention and treatment. Show less

Protists are polyphyletic single-celled eukaryotes that underpin global ecosystem functioning, particularly in the oceans. Most remain uncultured, limiting the investigation of their physiology and cell biology. MArine STramenopiles (MASTs) are heterotrophic protists that, although related to well-characterized photosynthetic diatoms and parasitic oomycetes, are poorly studied. The Nanomonadea (MAST-3) species Show less

Multiplexed assays of variant effect (MAVEs) systematically measure variant function but have been limited to cancer cell lines rather than disease-relevant cell types. We developed saturation genome editing in human iPSCs (iPSC-SGE) to introduce variant libraries into a single allele of a target gene while programming the genetic background of the second allele, enabling variant assessment across differentiated cell types and genetic contexts at scale. We edited 1,137 variants into Show less

Atrial fibrillation (AF) is a prevalent and morbid abnormality of the heart rhythm with a strong genetic component. Here, we meta-analyzed genome and exome sequencing data from 36 studies that included 52,416 AF cases and 277,762 controls. In burden tests of rare coding variation, we identified novel associations between AF and the genes MYBPC3, LMNA, PKP2, FAM189A2 and KDM5B. We further identified associations between AF and rare structural variants owing to deletions in CTNNA3 and duplications of GATA4. We broadly replicated our findings in independent samples from MyCode, deCODE and UK Biobank. Finally, we found that CRISPR knockout of KDM5B in stem-cell-derived atrial cardiomyocytes led to a shortening of the action potential duration and widespread transcriptomic dysregulation of genes relevant to atrial homeostasis and conduction. Our results highlight the contribution of rare coding and structural variants to AF, including genetic links between AF and cardiomyopathies, and expand our understanding of the rare variant architecture for this common arrhythmia. Show less

To broaden our understanding of bradyarrhythmias and conduction disease, we performed common variant genome-wide association analyses in up to 1.3 million individuals and rare variant burden testing in 460,000 individuals for sinus node dysfunction (SND), distal conduction disease (DCD) and pacemaker (PM) implantation. We identified 13, 31 and 21 common variant loci for SND, DCD and PM, respectively. Four well-known loci (SCN5A/SCN10A, CCDC141, TBX20 and CAMK2D) were shared for SND and DCD, while others were more specific for SND or DCD. SND and DCD showed a moderate genetic correlation (r Show less