Distribution and effect of ghrelin genotype on plasma lipid and apolipoprotein profiles in obese and nonobese Chinese subjects

The role of leptin and ghrelin in the regulation of appetite in obesity

Leptin and ghrelin are two key hormones that play opposing roles in the regulation of appetite and energy balance. Ghrelin stimulates appetite and food intake following binding to receptors and the subsequent activation of orexigenic neurons in the arcuate nucleus. Leptin, conversely, has been demonstrated to suppress appetite and reduce food intake. This occurs through the inhibition of ghrelin-activated neurons, while simultaneously activating those that promote satiety and increase energy expenditure. A lack of biological response despite elevated leptin levels, which is known as leptin resistance, is observed in individuals with excess body weight and represents a significant challenge. As the dysregulation of ghrelin and leptin signalling has been linked to the development of obesity and other metabolic disorders, an in-depth understanding of the genetic determinants affecting these two hormones may facilitate a more comprehensive grasp of the intricate interactions that underpin the pathogenesis of obesity.

The sex-specific relationship of ghrelin and cognition in Chinese han first-episode drug-naive major depressive disorder

In major depressive disorder (MDD), alterations in ghrelin levels and cognitive impairment coexist, yet their association has remained largely elusive. This study aimed to investigate the association between ghrelin levels and cognition in both MDD patients and healthy controls (HCs) while also exploring sex-specific differences in this correlation. A total of 155 Chinese Han subjects, including 90 first-episode drug-naive MDD patients and 65 HCs, were enrolled. Ghrelin levels were measured using ELISA kits, and neurocognitive assessments were conducted using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). MDD patients exhibited significantly higher ghrelin levels and lower cognitive scores of RBANS compared to HCs. However, there was no significant correlation between ghrelin levels and cognitive function in both MDD patients and HCs. Exploratory analyses revealed sex-specific associations between ghrelin and cognitive function, particularly in MDD patients. Females with MDD showed distinct patterns of association between ghrelin levels and cognitive domains such as attention and language, which were not observed in healthy controls or male MDD patients. The relationship between ghrelin and cognition only existed in MDD patients, not in the HCs, and there was a sex-specific difference in this association. Further research on the mechanism of ghrelin in the cognitive function of MDD should focus on sex differences.

Association of cerebrospinal fluid NPY with peripheral ApoA: a moderation effect of BMI

BACKGROUND

Apoprotein A-I (ApoA-I) and Apoprotein B (ApoB) have emerged as novel cardiovascular risk biomarkers influenced by feeding behavior. Hypothalamic appetite peptides regulate feeding behavior and impact lipoprotein levels, which effects vary in different weight states. This study explores the intricate relationship between body mass index (BMI), hypothalamic appetite peptides, and apolipoproteins with emphasis on the moderating role of body weight in the association between neuropeptide Y (NPY), ghrelin, orexin A (OXA), oxytocin in cerebrospinal fluid (CSF) and peripheral ApoA-I and ApoB.

METHODS

In this cross-sectional study, we included participants with a mean age of 31.77 ± 10.25 years, categorized into a normal weight (NW) (n = 73) and an overweight/obese (OW/OB) (n = 117) group based on BMI. NPY, ghrelin, OXA, and oxytocin levels in CSF were measured.

RESULTS

In the NW group, peripheral ApoA-I levels were higher, while ApoB levels were lower than in the OW/OB group (all p < 0.05). CSF NPY exhibited a positive correlation with peripheral ApoA-I in the NW group (r = 0.39, p = 0.001). Notably, participants with higher CSF NPY levels had higher peripheral ApoA-I levels in the NW group and lower peripheral ApoA-I levels in the OW/OB group, showing the significant moderating effect of BMI on this association (R2 = 0.144, β=-0.54, p < 0.001). The correlation between ghrelin, OXA and oxytocin in CSF and peripheral ApoB in both groups exhibited opposing trends (Ghrelin: r = -0.03 and r = 0.04; OXA: r = 0.23 and r=-0.01; Oxytocin: r=-0.09 and r = 0.04).

CONCLUSION

This study provides hitherto undocumented evidence that BMI moderates the relationship between CSF NPY and peripheral ApoA-I levels. It also reveals the protective role of NPY in the NW population, contrasting with its risk factor role in the OW/OB population, which was associated with the at-risk for cardiovascular disease.

Effect of the GHRL gene (rs696217) polymorphism on the metabolic disorders in patients with obesity in the Ukrainian population

Objective. Over the past four decades, the prevalence of obesity has tripled and limited genetic studies with specific SNPs have been conducted, but no investigations using ghrelin and obestatin prepropeptide (GHRL) gene have been reported in the Ukrainians population. The aim of this study was to evaluate changes in the level of metabolic hormones in the blood of obese patients in relation to the GHRL (rs696217) polymorphism. Methods. The study involved 53 obesity cases and 48 non-obesity subjects (controls). The GHRL (rs696217) polymorphism was genotyped using a TaqMan real-time polymerase chain reaction method. Blood hormones were determined with commercially available kits using a Multi-skan FC analyzer. Results. Carriers of the T allele of the GHRL (rs696217) polymorphism were statistically significantly more in patients diagnosed with obesity compared to controls indicating a genetically determined cause of obesity. We also established a significant effect of the presence of the T allele of the GHRL (rs696217) polymorphism on the decrease in the adiponectin level and the increase of resistin level in obese patients. The study of the effect of genotypes (TT, GT, GG) of the GHRL (rs696217) polymorphism on the metabolic hormone levels in the blood of obese patients did not show reliably significant differences. Conclusions. The presence of the T allele of the GHRL (rs696217) polymorphism in Ukrainian population indicates an increased risk of the obesity development regardless on the homozygous or heterozygous genotype.

Impact of gene polymorphism of glutathione S-transferase and ghrelin as a risk factor in Egyptian women with gestational diabetes mellitus

Background

Gestational diabetes mellitus is the most common metabolic dysfunction that arises during pregnancy. GDM can lead to serious health complications for both the mother during pregnancy and after the delivery of the baby. Additionally, mother–offspring suffers from abnormalities in metabolism. The study aimed to investigate glutathione S‑transferase P1 and ghrelin genetic variants in pregnant women diagnosed with gestational diabetes using a tetra-primer amplification refractory mutation system.

Results

This study demonstrated that the frequencies of genotypes in women with GDM were GSTP1-AG (87.1%) and GHRL-GG (100%). The study revealed no significant differences in the frequency of either genotype or allele of both GSTP1 and ghrelin between GDM and healthy pregnant women.

Conclusions

This study may be the first study designed to demonstrate that there is no association between the genotype and allele frequencies of GSTP1 (rs1695) and ghrelin (rs696217) in the development of gestational diabetes mellitus in Egyptian women.