Fat Mass and Obesity Associated Gene Variants Are Associated With Increased Growth Hormone Levels and Affect Glucose and Lipid Metabolism in Lean Women

Insights into the physiology of C-peptide

Current knowledge suggests a complex role of C-peptide in human physiology, but its mechanism of action is only partially understood. The effects of C-peptide appear to be variable depending on the target tissue, physiological environment, its combination with other bioactive molecules such as insulin, or depending on its concentration. It is apparent that C-peptide has therapeutic potential for the treatment of vascular and nervous damage caused by type 1 or late type 2 diabetes mellitus. The question remains whether the effect is mediated by the receptor, the existence of which is still uncertain, or whether an alternative non-receptor-mediated mechanism is responsible. The Institute of Endocrinology in Prague has been paying much attention to the issue of C-peptide and its metabolic effect since the 1980s. The RIA methodology of human C-peptide determination was introduced here and transferred to commercial production. By long-term monitoring of C-peptide oGTT-derived indices, the Institute has contributed to elucidating the pathophysiology of glucose tolerance disorders. This review summarizes the current knowledge of C-peptide physiology and highlights the contributions of the Institute of Endocrinology to this issue.

The role of FTO variants in the susceptibility of polycystic ovary syndrome and in vitro fertilization outcomes in Chinese women

We investigated the association between single nucleotide polymorphisms (SNPs) in the fat mass and obesity associated (FTO) gene (rs9926289 A/G, rs79206939 A/G, rs9930506 A/G, rs8050136 A/C, and rs1588413 C/T) and polycystic ovary syndrome (PCOS), as well as outcomes of in vitro fertilization (IVF). A case-control study consisting of 147 PCOS patients and 120 healthy controls was conducted. FTO SNPs were genotyped by PCR to determine allelic frequencies, and IVF outcomes were analyzed. The results showed that FTO rs8050136 (p = .025) and rs1588413 (p = .042) were significantly associated with PCOS susceptibility, and women with risk alleles were often found to be obese (p < .05). For SNP rs8050136, women with AA + AC genotypes had higher body mass indexes (BMIs), oral glucose tolerance test/2 h (OGTT) levels and implantation rates but lower follicle-stimulating hormone (FSH) and human chorionic gonadotropin (hCG) day progesterone levels and ovulation numbers (all p < .05) than those with the CC genotype. For SNP rs1588413, women carrying risk alleles exhibited higher BMIs, implantation rate, and levels of luteinizing hormone (LH), estradiol, and OGTT/2 h (all p < .05) compared with those with non-risk genotypes. Therefore, these findings suggest that rs8050136 and rs1588413 are associated with PCOS susceptibility, and that women with risk alleles have less ovulation numbers but higher implantation rates than those with other genotypes.