Regulation of Gastric Nesfatin-1/NUCB2
CURRENT PHARMACEUTICAL DESIGN
Authors: Li, Ziru; Mulholland, Michael; Zhang, Weizhen
Abstract
Originally identified in the hypothalamus as a satiety factor, recent studies provide evidence that nefatin-1/NUCB2 is a gutbrain peptide with a broader array of actions. Detection of abundant nesfatin-1/NUCB2 in gastric X/A like endocrine cells, which also produce the orexigenic hormone ghrelin, indicates that gastric mucosa may be one of the predominant sources of nesfatin-1/NUCB2. Functional studies have revealed significant effects of nefatin-1 on inhibition of feeding behavior and on glucose homeostasis. These metabolic functions make nesfatin-1/NUCB2 a novel candidate for treatment of obesity and diabetes. However, deficiencies in our understanding of nesfatin-1/NUCB2 receptor pose a significant hurdle for therapies that target its action. Defining novel pathways to alter the production of nesfatin-1/NUCB2 would shift therapeutic focus to gastric targets. A necessary precondition is improved understanding of the mechanisms by which nesfatin-1/NUCB2 is synthesized and secreted by gastric X/A like cells. Recent studies provide evidence that mTOR is a critical regulatory molecule in these endocrine cells and that its activity is linked to the production of ghrelin and nesfatin- 1/NUCB2. These findings suggest that gastric mTOR is involved in the regulation of food intake and overall energy metabolism through modulation of ghrelin and nesfatin-1/NUCB2. In this review, we first summarize current advances in the relationship between organism energy status and nesfatin-1/NUCB2 levels, and then discuss the novel finding on mTOR as the gastric fuel sensor and its role in the regulation of nesfatin-1/NUCB2 expression.
NUCB2 gene polymorphism and its relationship with nesfatin-1 levels in polycystic ovary syndrome
GYNECOLOGICAL ENDOCRINOLOGY
Authors: Taskin, Mine Islimye; Eser, Betul; Adali, Ertan; Kara, Hayrettin; Cuce, Coskun; Hismiogullari, Adnan Adil
Abstract
Nesfatin-1, encoded by the nucleobindin-2 (NUCB2) gene, is an anorexigenic protein related to energy metabolism, obesity, and insulin resistance. The aim of this study was to evaluate NUCB2 gene polymorphism (rs757081) and its association with serum levels of nesfatin-1 in obese and non-obese women with polycystic ovary syndrome (PCOS). In the study population, we analyzed 60 patients with PCOS and 26 age-matched healthy women as controls. The patients with PCOS were divided into two groups based on body mass index (BMI): obese group (n=28) or non-obese group (n=32). NUCB2 was genotyped using the polymerase chain reaction-restriction (PCR) technique. Serum nesfatin-1 level was measured by enzyme-linked immunosorbent assay (ELISA). Nesfatin-1 levels in the obese PCOS group were significantly lower than those in the non-obese PCOS and control groups (p<0.001). There was no statistically significant difference in the distribution of NUCB2 genotypes among the groups (p>0.05), whereas nesfatin-1 levels in the CC and CG genotypes were lower than those in the GG genotype. Nesfatin-1 decreases in PCOS, especially in obese women, and is negatively correlated with cardiometabolic risk factors. Although genotype disturbances of NUCB2 were similar among the groups, CC and CG genotypes accompanied lower nesfatin-1 levels. C allele of NUCB2 gene polymorphism and nesfatin-1 may play a role in the pathophysiology of PCOS.