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Oteng, A.-B.

Publications and source records attributed to Oteng, A.-B..

3 recordsLinked to original sources

A Multi-tissue Transcriptomic-Metabolomic Map Linking Maternal High-Fiber Diet to Reduced Offspring Type 2 Diabetes

BackgroundEarly-life nutritional exposures are increasingly recognized as critical determinants of long-term metabolic health, yet the molecular mechanisms linking maternal diet to offspring type 2 diabetes susceptibility remain incompletely understood. Experimental models are essential to disentangle maternal dietary effects from later-life metabolic influences. MethodsUsing the Nile rat, a genetically heterogeneous model of diet-induced diabetes, we quantified the impact of maternal high-fiber diet on offspring diabetes incidence using sex-stratified time-to-event analyses in 762 offspring. To identify molecular mediators, we performed transcriptomic profiling across 13 offspring tissues, independently contrasting maternal diet exposure and early-onset diabetes status. Overlapping differentially expressed genes were prioritized and evaluated for cardiometabolic associations in human whole-blood transcriptomic data from the GENE-FORECAST cohort. Untargeted plasma metabolomics was integrated to identify circulating metabolites associated with candidate genes. ResultsOffspring born to dams maintained on a high-fiber diet exhibited a markedly reduced risk of developing type 2 diabetes, with approximately 70% lower hazard of diabetes onset in both males and females compared with offspring from regular chow-fed dams. Multi-tissue transcriptomic analyses identified 147 genes differentially expressed in association with both maternal diet and early-onset diabetes, with most effects being tissue-specific. Asnsd1 uniquely showed consistent regulation across the aorta, brown adipose tissue, and skeletal muscle, with higher expression in offspring exposed to a high-fiber maternal diet and lower expression in offspring with early-onset diabetes. In human whole-blood transcriptomic data, ASNSD1 expression was significantly associated with blood pressure-related cardiometabolic traits, including hypertension, systolic blood pressure, and mean arterial pressure. In the animal model, circulating succinic acid was positively correlated with Asnsd1 expression in the aorta but not in other tissues. ConclusionsThis study provides a multi-tissue transcriptomic-metabolomic framework linking maternal high-fiber diet to reduced offspring type 2 diabetes risk. The findings identify ASNSD1 as a maternal diet-sensitive gene associated with diabetes susceptibility across multiple tissues and with cardiometabolic traits in humans, while highlighting tissue-specific relationships between gene expression and circulating metabolites. Together, these results offer mechanistic insight into how early-life nutrition can durably influence diabetes risk across the life course.

developmental biology↗

Multi-omics Integration with GWAS Unveils Molecular Mechanistic Insights for Type 2 Diabetes

BackgroundType 2 diabetes (T2D) is a complex metabolic disorder driven by genetic and environmental factors. While genome-wide association studies (GWAS) have identified numerous T2D-associated variants, many remain functionally uncharacterized. Integration of GWAS with molecular phenotyping offers a path to revealing biological relevance. We investigated the influence of GWAS-variants, including sub-threshold T2D-associated variants (GWAS p-value [≤] 0.0001), on gene and protein expression to assign functional relevance. MethodsGenetic variants associated with T2D in the GWAS Catalog and present in our whole-genome sequencing (WGS) data were used to perform expression quantitative trait loci (eQTL) analysis in 242 whole-blood mRNA-sequenced samples. The same variants were used to perform protein quantitative trait loci (pQTL) analysis in a set of 362 plasma samples profiled on the Olink platform. For each analysis, the datasets were randomly split into discovery and validation subsets. Associations between variants and mRNA or protein levels were tested by multiple linear regression, and only QTLs that reached a false discovery rate adjusted p-value [≤] 0.05 in the discovery dataset and replicated in the validation dataset (p [≤] 0.05) with same direction of effect were carried forward. QTL-linked mRNAs and proteins were subsequently evaluated for their relationship with T2D status to connect them with T2D pathophysiology. ResultsWe identified 1,291 eQTLs linked to 97 mRNAs and 1,273 pQTLs linked to 22 proteins. Among these, 10 mRNAs and 5 proteins were differentially expressed between non-diabetic and diabetic individuals. Notably, LPL, APOBR, APOM (lipid metabolism), NOTCH2, TREH ({beta}-cell/endocrine regulation), and HLA-A, OAS3 (immune response) converged on three biological axes central to T2D pathophysiology. The directionality of molecular effects was consistent with known disease mechanisms, including insulin resistance (LPL, APOBR), {beta}-cell stress (TREH, NOTCH2), and chronic inflammation (OAS3). ConclusionsOur findings indicate that variants falling below conventional GWAS significance thresholds can have demonstrable effects on gene expression and protein levels. This underscores the importance of prioritizing biological relevance alongside statistical significance, rather than relying solely on rigid p-value cutoffs.

genomics↗

Absence of muricholic acid due to Cyp2c-deficiency protects against high fat diet-induced obesity in male mice but promotes liver damage

ObjectiveMurine-specific muricholic acids (MCAs) are reported to protect against obesity and associated metabolic disorders. However, the response of mice with genetic depletion of MCA to an obesogenic diet has not been evaluated. We used Cyp2c-deficient (Cyp2c-/-) mice, which lack MCAs and thus have a human-like bile acid (BA) profile, to directly investigate the potential role of MCAs in diet-induced obesity. MethodsMale and female Cyp2c-/- mice and wild-type controls were fed a standard chow diet or a high fat diet (HFD) for 18 weeks. We measured BA composition from a pool of liver, gallbladder, and intestine, as well as weekly body weight, food intake, lean and fat mass, systemic glucose homeostasis, energy expenditure, intestinal lipid absorption, fecal lipid, and energy content. ResultsCyp2c deficiency depleted MCAs and caused other changes in BA composition, namely a decrease in the ratio of 12-hydroxylated (12-OH) BAs to non-12-OH BAs, without altering the total BA levels. While wild-type male mice became obese after HFD-feeding, Cyp2c-/- male mice were protected from obesity and associated metabolic dysfunctions. Cyp2c-/- male mice also showed reduced intestinal lipid absorption and increased lipid excretion, which was reversed by oral gavage with the 12-OH BA, taurocholic acid. Cyp2c-/- mice also showed increased liver damage, which appeared stronger in females. ConclusionMCA does not protect against diet-induced obesity but may protect against liver injury. Reduced lipid absorption in Cyp2c-deficient male mice is potentially due to a reduced ratio of 12-OH/non-12-OH BAs.

physiology↗