Secondly, maternal obesity (in the absence of gestational diabetes) was associated with (i) elevated DNA methylation of the leptin promoter on fetal side only, (ii) hypomethylation of the adiponectin promoter on the maternal side only, (iii) significantly low levels of leptin receptor protein (albeit in the absence of differences in mRNA levels and promoter DNA methylation), (iv) significantly low levels of adiponectin receptor 1 mRNA expression on the maternal side only, and (v) elevated DNA methylation of the adiponectin receptor 2 promoter on the maternal side only.
Upregulation of ADIPOR1 and SPP1, among the adipokine gene family, in cancer tissue is associated with poor survival in CRC, suggesting a potential mechanism linking obesity and CRC.
BACKGROUND Adiponectin receptor-1 (AdipoR1) has been reported to be associated with the risk of obesity-associated malignancies, including epithelial ovarian cancer (EOC).
The established link between obesity and RCC can therefore be further explained by the adiponectin deficiency in obese individuals together with reduced AdipoR1 protein in RCC.
Polymorphisms in adiponectin-related genes (ADIPOQ, ADIPOR1, ADIPOR2) have been examined for relationships with obesity, insulin resistance and diabetes, cardiovascular disease, and to circulating adipokine levels, but many gaps in knowledge remain.
Because adiponectin is a candidate gene for common obesity, it is also hypothesized that variations in AdipoR1 may be involved in the development of complex obesity.
Adiponectin levels are highly heritable and several single-nucleotide polymorphisms (SNPs) in adiponectin-related genes (ADIPOQ, ADIPOR1, ADIPOR2) have been examined in relation to circulating adiponectin levels and obesity phenotypes, but despite differences in adiponectin levels and obesity prevalence by race, few studies have included black participants.
Correlation analyses between the genetic circadian oscillation and components of the metabolic syndrome revealed that adiposity and abdominal obesity correlated with a decrease in adiponectin and adiponectin receptors ADIPOR1 and ADIPOR2 amplitude (P < 0.05).
The aim of this study was to explore whether lymphocyte ADIPOR1 and ADIPOR2 mRNA expression is associated with obesity, insulin resistance, first-phase insulin secretion and serum adiponectin levels.
AdipoR2 expression was slightly decreased in adipose tissue, whereas the expression of both AdipoR1 and AdipoR2 was increased (P < .05) in the liver of obese Zucker rats.
Circulating adiponectin was negatively associated, whereas AdipoR1/R2 mRNA levels were positively associated with obesity, glucose and lipid levels, and insulin resistance.