A genome-wide search for gene-by-obesity interaction loci of dyslipidemia in Koreans shows diverse genetic risk alleles

Joint and interactive associations of body mass index and genetic factors with cardiovascular disease: a prospective study in UK Biobank

BACKGROUND

Both body mass index (BMI) and genetic factors independently contribute to cardiovascular disease (CVD). However, it is unclear whether genetic risk modifies the association between BMI and the risk of incident CVD. This study aimed to investigate whether BMI categories and genetic risk jointly and interactively contribute to incident CVD events, including hypertension (HTN), atrial fibrillation (AF), coronary heart disease (CHD), stroke, and heart failure (HF).

METHODS

A total of 496,851 participants from the UK Biobank with one or more new-onset CVD events were included in the analyses. BMI was categorized as normal weight (< 25.0 kg/m2), overweight (25.0-29.9 kg/m2), and obesity (≥ 30.0 kg/m2). Genetic risk for each outcome was defined as low (lowest tertile), intermediate (second tertile), and high (highest tertile) using polygenic risk score. The joint associations of BMI categories and genetic risk with incident CVD were investigated using Cox proportional hazard models. Additionally, additive interactions were evaluated.

RESULTS

Among the 496,851 participants, 270,726 (54.5%) were female, with a mean (SD) age was 56.5 (8.1) years. Over a median follow-up (IQR) of 12.4 (11.5-13.1) years, 102,131 (22.9%) participants developed HTN, 26,301 (5.4%) developed AF, 32,222 (6.9%) developed CHD, 10,684 (2.2%) developed stroke, and 13,304 (2.7%) developed HF. Compared with the normal weight with low genetic risk, the obesity with high genetic risk had the highest risk of CVD: HTN (HR: 3.96; 95%CI: 3.84-4.09), AF (HR: 3.60; 95%CI: 3.38-3.83), CHD (HR: 2.76; 95%CI: 2.61-2.91), stroke (HR: 1.44; 95%CI: 1.31-1.57), and HF (HR: 2.47; 95%CI: 2.27-2.69). There were significant additive interactions between BMI categories and genetic risk for HTN, AF, and CHD, with relative excess risk of 0.53 (95%CI: 0.43-0.62), 0.67 (95%CI: 0.51-0.83), and 0.37 (95%CI: 0.25-0.49), respectively.

CONCLUSIONS

BMI and genetic factors jointly and interactively contribute to incident CVD, especially among participants with high genetic risk. These findings have public health implications for identifying populations more likely to have cardiovascular benefit from weight loss interventions.

Effect of Green and Red Thai Kratom (Mitragyna speciosa) on pancreatic digestive enzymes (alpha-glucosidase and lipase) and acetyl-carboxylase 1 activity: A possible therapeutic target for obesity prevention

Regular use of Thai kratom has been linked to reduced blood triglyceride levels and body mass index (BMI) in healthy individuals. We analyzed Green Thai Kratom (GTK) and Red Thai Kratom (RTK) to investigate their effects on pancreatic digestive enzymes. The ethanol extracts of GTK and RTK inhibited lipase activity more strongly than alpha-glucosidase activity, suggesting the presence of lipase inhibitors. Mitragynine, the major compound in GTK, showed potent lipase inhibition and moderate alpha-glucosidase inhibition. Quercetin, found in both extracts, strongly inhibited alpha-glucosidase but had limited effects on lipase. These findings suggest that mitragynine and quercetin may hinder triglyceride and starch digestion. Combination inhibition studies revealed synergistic effects between mitragynine and quercetin on alpha-glucosidase activity. Additionally, both GTK and RTK extracts reduced fat accumulation in 3T3-L1 adipocyte cells, with quercetin specifically inhibiting Acetyl-CoA carboxylase 1 (ACC1), a key enzyme in fatty acid biosynthesis. Thus, GTK and RTK extracts, particularly mitragynine and quercetin, exhibit potential anti-obesity effects. We report the novel finding that Thai kratom inhibits de novo fatty acid synthesis by targeting ACC1, resulting in decreased fat accumulation in adipocytes. Regular use of Thai kratom in specific populations may improve blood triglyceride levels and reduce BMI by inhibiting lipase, alpha-glucosidase, and ACC1 activity. Further clinical trials are needed to determine optimal dosage, duration, toxicity levels, and potential side effects of Kratom use.

Interaction of metabolism-related pathway gene variants with bisphenol A exposure on serum lipid profiles

Bisphenol A (BPA) can be metabolized by metabolic enzymes and may induce abnormal lipid metabolism. We hypothesized that BPA exposure and its interaction with metabolism-related genes might be associated with serum lipid profiles. We performed a two-stage study among 955 middle-aged and elderly participants in Wuhan, China. Urinary BPA level was estimated without (BPA, μg/L) or with (BPA/Cr, μg/g) adjustments for urinary creatinine and ln-transformed values (ln-BPA or ln-BPA/Cr) were used to normalize the asymmetrical distributions. A total of 412 metabolism-related gene variants were selected and used for gene-BPA interaction analysis. Multiple linear regression was used to analyze the interactions between BPA exposure and metabolism-related genes on serum lipid profiles. In the discovery stage, both ln-BPA and ln-BPA/Cr was associated with decreased high-density lipoprotein cholesterol (HDL-C). Gene-urinary BPA interaction for IGFBP7 rs9992658 was observed to associate with HDL-C levels in both discovery and validation stages, with P_interaction equal to 9.87×10^-4 (ln-BPA) and 1.22×10^-3 (ln-BPA/Cr) in combined analyses. In addition, the inverse association of urinary BPA with HDL-C levels was only observed among individuals carrying rs9992658 AA genotype, but not in individuals carrying rs9992658 AC or CC genotypes. The interaction between BPA exposure and metabolism-related gene IGFBP7 (rs9992658) was associated with HDL-C levels. AVAILABILITY OF DATA AND MATERIAL: Not applicable.

Specific Functions of Melanocortin 3 Receptor (MC3R)

Melanocortin 3 receptor (MC3R) is a G-protein coupled receptor which has been defined mostly as a regulator of the appetite/hunger balance mechanisms to date. In addition to its function regarding the weight gain and appetite control mechanisms of MC3R, recent studies have shown that MC3R controls growth, puberty, and circadian rhythms as well. Despite the drastic effects of MC3R deficiency in humans and other mammals, its cellular mechanisms are still under investigation. In this review paper, we aimed to point out the importance of MC3R regulations in three main areas: 1) its impact on weight and appetite control, 2) its role in the control of growth, puberty, and the circadian rhythm, and, 3) its protein-protein interactions and cellular mechanisms.

Haplotype of ESR1 and PPARD Genes Is Associated with Higher Anthropometric Changes in Han Chinese Obesity by Adjusting Dietary Factors-An 18-Month Follow-Up

The obesity genetic effect may play a major role in obesogenic environment. A combined case-control and an 18-month follow-up were carried out, including a total of 311 controls and 118 obese cases. All participants were aged in the range of 20-55 y/o. The body mass index (BMI) of obese cases and normal controls was in the range of 27.0-34.9 and 18.5-23.9 kg/m², respectively. The rs712221 on Estrogen receptor1 (ESR1) and rs2016520 on Peroxisome proliferator-activated receptor delta (PPARD) showed significant associations with obesity. The TT (odds ratio (OR): 2.42; 95% confidence interval (CI): 1.46-4.01) and TT/TC (OR: 2.80; 95% CI: 1.14-6.85) genotypes on rs712221 and rs2016520 had significantly higher obesity risks, respectively. Moreover, the synergic effect of these two risk SNPs (2-RGH) exhibited an almost geometrical increase in obesity risk (OR: 7.00; 95% CI: 2.23-21.99). Obese individuals with 2-RGH had apparently higher changes in BMI increase, body weight gain and dietary fiber intake but a lower total energy intake within the 18-month follow-up.