Munc18c is associated with glucose metabolism and could play a relevant role in obesity. However, little is known about the regulation of Munc18c expression. We analyzed Munc18c gene expression in hum Show more
Munc18c is associated with glucose metabolism and could play a relevant role in obesity. However, little is known about the regulation of Munc18c expression. We analyzed Munc18c gene expression in human visceral (VAT) and subcutaneous (SAT) adipose tissue and its relationship with obesity and insulin. We evaluated 70 subjects distributed in 12 non-obese lean subjects, 23 overweight subjects, 12 obese subjects and 23 nondiabetic morbidly obese patients (11 with low insulin resistance and 12 with high insulin resistance). The lean, overweight and obese persons had a greater Munc18c gene expression in adipose tissue than the morbidly obese patients (p<0.001). VAT Munc18c gene expression was predicted by the body mass index (B = -0.001, p = 0.009). In SAT, no associations were found by different multiple regression analysis models. SAT Munc18c gene expression was the main determinant of the improvement in the HOMA-IR index 15 days after bariatric surgery (B = -2148.4, p = 0.038). SAT explant cultures showed that insulin produced a significant down-regulation of Munc18c gene expression (p = 0.048). This decrease was also obtained when explants were incubated with liver X receptor alpha (LXRα) agonist, either without (p = 0.038) or with insulin (p = 0.050). However, Munc18c gene expression was not affected when explants were incubated with insulin plus a sterol regulatory element-binding protein-1c (SREBP-1c) inhibitor (p = 0.504). Munc18c gene expression in human adipose tissue is down-regulated in morbid obesity. Insulin may have an effect on the Munc18c expression, probably through LXRα and SREBP-1c. Show less
The apolipoprotein AI-CIII-AIV cluster has been associated with the response to a urate-lowering diet, and polymorphisms in the apolipoprotein CIII gene have been associated with hyperuricemia and hyp Show more
The apolipoprotein AI-CIII-AIV cluster has been associated with the response to a urate-lowering diet, and polymorphisms in the apolipoprotein CIII gene have been associated with hyperuricemia and hypertriglyceridemia. We assessed the influence of polymorphisms in the apolipoprotein AI-CIII-AIV cluster on the response to a urate-lowering diet in patients with hyperuricemia. A urate-lowering diet was followed for 2 weeks by 64 men with hyperuricemia. Plasma concentrations of triglycerides, cholesterol, glucose, and uric acid, and the uric acid clearance and 24-hour uric acid urinary excretory fraction were measured before and after the diet. The data were analyzed in association with the polymorphisms of the apolipoprotein AI-CIII-AIV gene cluster. After the urate-lowering diet, the plasma levels of triglycerides, cholesterol, glucose, and uric acid and 24-hour uric acid excretion all fell significantly. Paired sample ANOVA showed that the decrease was mainly due to the diet, except for the plasma triglycerides, which were influenced by allele X2 of the XmnI polymorphism of the apolipoprotein AI gene. The response of the biological variables to a urate-lowering diet was mainly influenced by diet. Changes in triglycerides were also influenced by the apolipoprotein AI XmnI polymorphism (p = 0.04), suggesting a gene-diet interaction (p = 0.03). Show less