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Metabolic and bariatric surgery (MBS) effectively treats obesity and related comorbidities, though individual responses vary. This systematic review examines how genetic variants influence MBS outcomes in morbidly obese patients. A comprehensive search in PubMed, Embase, Medline, and the Cochrane Library identified 1572 studies, with 52 meeting the inclusion criteria. Two reviewers independently filtered and selected studies, including relevant cross-references. Research focused on polymorphisms in genes such as UCP2, UCP3, 5-HT2C, MC4R, FKBP5, FTO, CAT haplotypes, LYPAL-1, PTEN, FABP-2, CNR1, LEP656, LEP223, GLP-1R, APOA-1, APOE, ADIPOQ, IL-6, PGC1a, TM6SF2, MBOAT7, PNPLA3, TCF7L2, ESR1, GHSR, GHRL, CD40L, DIO2, ACSL5, CG, TAS2R38, CD36, OBPIIa, NPY, BDNF, CLOCK, and CAMKK2. Most studies explored associations with post-surgery weight loss, while some examined metabolic, cardiovascular, taste, and eating behavior effects as well. Understanding the role of genetic factors in weight loss and metabolic outcomes post-MBS can help tailor personalized treatment plans for improved efficacy and long-term success. Further research with larger sample sizes and extended follow-up is needed to clarify the effects of many genetic variants on MBS outcomes in morbidly obese patients. Show less

The increased prevalence of metabolic diseases in the Arab countries is mainly associated with genetic susceptibility, lifestyle behaviours, such as physical inactivity, and an unhealthy diet. The objective of this review was to investigate and summarise the findings of the gene-lifestyle interaction studies on metabolic diseases such as obesity and type 2 diabetes in Arab populations. Relevant articles were retrieved from a literature search on PubMed, Web of Science, and Google Scholar starting at the earliest indexing date through to January 2024. Articles that reported an interaction between gene variants and diet or physical activity were included and excluded if no interaction was investigated or if they were conducted among a non-Arab population. In total, five articles were included in this review. To date, among three out of twenty-two Arab populations, fourteen interactions have been found between the Show less

Polymorphisms in the melanocortin 4 receptor (MC4R) gene with occurrence and progression of chronic diseases such as obesity and cardiovascular disease (CVD) have long been addressed but there is a lack of evidence for complex interrelationships, including direct and indirect effects of these variables. This review specifically focuses on studying the effects of healthy diet interaction and MC4R polymorphisms on the development of CVD. The quantity and quality of carbohydrates and proteins consumed are related to obesity susceptibility and cardiometabolic risk factors. A healthy dietary pattern such as a Mediterranean dietary can modulate the association between MC4R polymorphisms (rs17782313) and the risk of CVDs. Also, the Nordic diet can reduce lipid profiles such as low-density lipoprotein cholesterol (LDL-C) and total cholesterol levels. On the other hand, MC4R interaction with the dietary inflammatory index decreases high-density lipoprotein cholesterol levels and increases LDL-C and triglyceride (TG) levels. Additionally, the DASH diet decreases TG, atherogenic index of plasma, systolic blood pressure, diastolic blood pressure, and serum glucose. The interaction between MC4R genes and diets plays an important role in the development of CVD. Adherence to healthy diets such as the Mediterranean, Nordic, Anti-inflammatory, and Dash diets might be an efficient strategy to prevent CVD. The potential for personalized diets to be developed for the treatment and prevention of CVD and its related comorbidities is expected to expand as this field develops. Show less

The aim of our study is to investigate in vitro and in vivo MC4R as a novel target in melanoma using the selective antagonist ML00253764 (ML) alone and in combination with vemurafenib, a B-rafV600E inhibitor. The human melanoma B-raf mutated A-2058 and WM 266-4 cell lines were used. An MC4R null A-2058 cell line was generated using a CRISPR/Cas9 system. MC4R protein expression was analysed by western blotting, immunohistochemistry, and immunofluorescence. Proliferation and apoptotic assays were performed with ML00253764, whereas the synergism with vemurafenib was evaluated by the combination index (CI) and Loewe methods. ERK1/2 phosphorylation and BCL-XL expression were quantified by western blot. In vivo experiments were performed in Athymic Nude-Foxn1 Show less

Metabolic dysfunction-associated steatotic liver disease is the most common form of liver disease and poses significant health risks to patients who progress to metabolic dysfunction-associated steatohepatitis. Fatty acid overload alters endoplasmic reticulum (ER) calcium stores and induces mitochondrial oxidative stress in hepatocytes, leading to hepatocellular inflammation and apoptosis. Obese mice have impaired liver sarco/ER Ca Show less

To explore the potential impact of lipid metabolism-related single nucleotide polymorphisms (SNP) on semen quality in men. We selected 284 semen samples from Xingtai Infertility Hospital and Hebei Human Sperm Bank collected between February and October 2023, 33 from oligozoospermia (OS), 97 from asthenozoospermia (AS) and 54 from oligoasthenozoospermia (OAS) patients and the other 100 from normal men. We performed computer-assisted semen analysis (CASA) of the samples, extracted blood DNA and, using the MassARRAY System, genotyped the target genes, determined the genotypes of 13 SNPs and compared their distribution, their correlation with BMI and semen quality in different groups. The mutant homozygous (TT) genotype of the FADS2 rs2727270 gene seemed to be a risk factor for AS (OR = 4.420, P= 0.047), while the APOA2 rs5082-A allele and MC4R rs17782313 heterozygous (TC) genotype important protective factors for OS (OR = 0.422 and 0.389; P= 0.045 and 0.043, respectively). A significantly higher sperm concentration was found associated with the MC4R rs17782313 heterozygous (TC) genotype than with the homozygous (CC) genotype. Stratification analysis showed that the protective effect of the TC genotype was decreased with increased BMI and remained with the interaction of the rs5082 and rs17782313 genotypes. FADS2 rs2727270, APOA2 rs5082 and MC4R rs17782313 were significantly correlated with the risk of abnormal semen parameters. Show less

α-Melanocyte stimulating hormone (α-MSH) is a peptide hormone released from the intermediate lobe of the pituitary which regulates body pigmentation. In addition to the pituitary, α-MSH is also produced in the midbrain, and exerts both anorexigenic and an anxiogenic actions. Acyl ghrelin and cholecystokinin are peripheral hormones derived from the digestive tract which affect the brain to control food intake and feeding behavior in vertebrates. In the present study, hypothesizing that plasma α-MSH may also stimulate the brain and exert central effects, we examined whether peripherally administered α-MSH affects food intake and psychomotor activity using a goldfish model. Intraperitoneal (IP) administration of α-MSH at 100 pmol g Show less

Rare cases of monogenic obesity, which may respond to specific therapeutics, can remain undetected in populations in which polygenic obesity is prevalent. This study examined rare DNA variation in established monogenic obesity genes within a community using whole-exome sequence data from 6803 longitudinally studied individuals. Exome data across 15 monogenic obesity genes were analyzed for nonsynonymous variants observed in any child with a maximum BMI z score > 2 (N = 279) but not observed in a child with a maximum BMI z score ≤ 0 (n = 1542) or that occurred in adults in the top 5th percentile of BMI (n = 263) but not in adults below the median BMI (n = 2629). Variants were then functionally analyzed using luciferase assays. The comparisons between cases of obesity and controls identified eight missense variants in six genes: DYRK1B, KSR2, MC4R, NTRK2, PCSK1, and SIM1. Among these, MC4R p.A303P and p.R165G were previously shown to impair MC4R function. Functional analyses of the remaining six variants suggest that KSR2 p.I402F and p.T193I and NTRK2 p.S249Y alter protein function. In addition to MC4R, rare missense variants in KSR2 and NTRK2 may potentially explain the severe obesity observed for the carriers. Show less

Obesity, a significant public health concern with high prevalence in both adults and children, is a complex disorder arising from the interaction of multiple genes and environmental factors. Advances in genome-wide association studies (GWAS) and sequencing technologies have identified numerous polygenic causes of obesity, particularly genes involved in hunger, satiety signals, adipocyte differentiation, and energy expenditure. This study investigates the relationship between six obesity-related genes ( Show less

Single nucleotide polymorphisms (SNPs) could increase the susceptibility of individuals to develop obesity and type 2 diabetes (T2DM). Obesity and T2DM are closely related pathophysiologically, thus similar SNPs could mediate both these diseases, but this is rarely reported. Furthermore, limited studies have been performed to summarize SNP data in the Asian population compared to the Western population. In this study, we aimed to summarize SNPs that are associated with the development of obesity and T2DM among Asian populations. We searched six literature databases and Review Manager (RevMan) was used for meta-analysis. The pooled odds ratios (ORs) and 95% CIs were calculated with a random effects model for the heterogeneity among studies. The pooled analysis showed that rs9939609 (FTO gene) and rs17782313 and rs571312 (MC4R gene) are associated with obesity with an odd ratio (OR) of 1.37, 1.36 and 1.29 respectively. For T2DM, five SNPs, rs7903146 and rs12255372 (TCF7L2 gene), rs13266634 and rs11558471 (SLC30A8 gene) and rs2283228 (KCNQ1 gene) have also shown strong associations with T2DM at OR of 1.64, 1.61, 1.22, 1.29 and 1.60 respectively. This data could be used to develop a gene screening panel for assessing obesity and T2DM susceptibility. Show less

Humans are the result of an evolutionary process, and because of this, many biological processes are interconnected with each other. The intestine-brain axis consists of an intricately connected neuronal-neuroendocrine circuit that regulates the sensation of hunger and satiety. Genetic variations and the consumption of unnatural diets (ultra-processed foods, high contents of sugars, etc.) can override this circuit and cause addiction to certain foods and/or the inability to feel satiety in certain situations. The patients who come to consultations (mainly psychology or nutrition) in an attempt to resolve this problem sometimes fail, which leads to them looking for new strategies based on biological predisposition. This investigation aims to evaluate the genetic studies regarding the microbiota carried out in the last 12 years in humans to try to determine which genes and microbes that have been recently studied are related to patients diagnosed with binge eating disorder or compulsive eating (presenting obesity or not). The protocol followed the PRISMA statement, and the following databases were searched from 2012 until the present day: PubMed, PsycINFO, SCOPUS, and Web of Science. Twenty-four international articles were analyzed, including cross-sectional or exploratory studies; five of them referred to the microbial composition, and in nineteen, the existence of genetic polymorphisms present in binge eating disorder or in compulsive eating could be observed: DRD2, OPRM1, COMT, MC4R, BNDF, FTO, SLC6A3, GHRL, CARTPT, MCHR2, and LRP11. Even though there is still much to investigate on the subject, it must be highlighted that, in the last 4 years, a two-fold increase has been observed in potential markers and in studies related to the matter, also highlighting the importance of different analyses in relation to psychosocial factors and their interaction with the genetic and microbial factors, for which research on the matter must be continued. Show less

The CTNS gene mutation causes infantile nephropathic cystinosis (INC). Patients with INC develop Fanconi syndrome and chronic kidney disease (CKD) with significant bone deformations. C57BL/6 Ctns We first defined the time course of bone abnormalities in Ctns Bone defects are present in Ctns Our findings suggest a significant role for dysregulated leptin signalling in INC-related bone disorder, either directly or potentially involving a muscle-bone interplay. Leptin signalling blockade may represent a novel approach to treating bone disease as well as muscle wasting in INC. Show less

In a recent study by Zhao et al., rare protein-truncating variants (PTVs) in the BSN and APBA1 genes showed effects on obesity that exceeded those of well-known genes such as MC4R in a UK cohort. In this study, we leveraged the All of Us Research Program, to investigate the association of predicted LoF (pLoF) PTVs in BSN and APBA1 with body mass index (BMI) across a population of diverse ancestry. Our analysis revealed that the impact of pLoF variants in BSN and APBA1 on BMI was notably greater in this cohort, especially among individuals of European ancestry. Additionally, a phenome-wide association study (PheWAS) using the extensive phenotypic data available in the All of Us Research Program uncovered novel associations of Show less

The onset and progression mechanisms of metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) are being studied. We developed and analyzed a new mouse model of obesity by combining maternal Id-like molecule (Maid) and melanocortin-4 receptor (Mc4r) gene deletions. Four mice, each at 12 and 28 weeks of age, were analyzed for each genotype: Maid gene knockout, Mc4r gene knockout, combined Mc4r and Maid gene knockout, and Mc4r gene knockout with a high-fat diet. Mice with a combined deficiency of Mc4r and Maid gene showed significantly more severe obesity compared to all other genotypes, but no liver fibrosis or a decline in metabolic status were observed. In visceral white adipose tissue, Maid and Mc4r gene knockout mice had fewer CD11c-positive cells and lower mRNA expression of both inflammatory and anti-inflammatory cytokines. Furthermore, Maid and Mc4r gene knockout mice showed lower expression of adipocytokines in visceral white adipose tissue and uncoupling protein-1 in scapular brown adipose tissue. The expression of adipocytokines and uncoupling protein-1 is regulated by sympathetic nerve signaling that contribute severe obesity in Maid and Mc4r gene knockout mice. These mechanisms contribute hyperobesity in Maid and Mc4r gene knockout mice. Show less

Smith Magenis Syndrome (SMS) is a rare genetic disorder caused by RAI1 haploinsufficiency. Obesity in people with SMS is believed partially due to dysfunction of the proximal melanocortin 4 receptor (MC4R) pathway. We therefore studied effects of treatment with the MC4R agonist setmelanotide on obesity and hunger, as well as metabolic, cardiac and safety, in individuals with SMS. People with SMS received once-daily setmelanotide injections, with the dose titrated bi-weekly to a maximum of 3 mg over ∼1 month; and a full-dose treatment duration of 3mo. The primary outcome was percent change in body weight. Secondary outcomes included hunger, waist circumference, body composition, and safety. 12 individuals, ages 11-39 y, enrolled and 10 completed the full-dose treatment phase. Mean percent change in body weight at end-treatment was - 0.28 % [(95 % CI, -2.1 % to 1.5 %; n = 12; P = 0.66]. Participants experienced a significant decrease in total cholesterol associated with a significant decrease in HDL-cholesterol and a trend for lower LDL-cholesterol. Self-reported hunger was reduced at end-treatment (p = 0.011). All participants reported adverse events (AEs), most commonly injection-site reactions and skin hyperpigmentation. No AEs led to withdrawal or death. In this trial, setmelanotide did not significantly reduce body weight in participants with SMS. Participants reported significant differences in hunger, but such self-reports are difficult to interpret without a placebo-treated group. The changes in lipid profiles require further investigation. Results of this study do not suggest that dysfunction of the proximal MC4R pathway is the main etiology for obesity in people with SMS. Show less

Melanocortin-4 receptor (Mc4r) is a G protein-coupled receptor that controls systemic energy balance by regulating food intake and energy expenditure. Although the detailed molecular mechanism remains unclear, the activation of cAMP signaling in Mc4r-expressing cells reportedly suppresses food intake and increases energy expenditure. CREBP-regulated transcriptional coactivator-1 (CRTC1) is selectively expressed in neuronal cells and participates in transcriptional control, thereby contributing to neuronal plasticity and energy homeostasis. Considering the cAMP-dependent regulation of CRTC1 activity, CRTC1 in Mc4r-expressing cells may contribute to energy balance regulation through the melanocortin pathway. In this context, we examined the physiological contribution of CRTC1 in Mc4r-expressing cells to energy metabolism. In this study, mice with CRTC1 deficiency in Mc4r-expressing cells exhibited 1) modest obesity, glucose intolerance, insulin resistance, hyperinsulinemia, and hyperlipidemia; 2) decreased systemic energy expenditure and thermogenesis; 3) suppression of melanocortin agonist-induced adaptation of energy expenditure and food intake; 4) impaired thermogenic programs and oxidative pathway in brown adipose tissue and skeletal muscle; and 5) enhanced lipogenic programs in the liver and white adipose tissue. These results provide novel insights into the molecular mechanisms underlying the regulation of energy balance by the melanocortin system. Show less

DBI/ACBP (diazepam binding inhibitor, acyl-CoA binding protein) is produced by multiple cell types and detectable in blood plasma. DBI acts on GABRA (gamma-aminobutyric acid type A receptor) complexes containing GABRG2 (gamma-aminobutyric acid type A receptor, subunit gamma 2) to inhibit macroautophagy/autophagy and hence can be considered as an "autophagy checkpoint". In patients with poor-prognosis anorexia nervosa, as well as in mice developing stress-induced anorexia, circulating DBI levels are reduced. Using a chemical-genetic system that makes it possible to control DBI secretion by hepatocytes, we showed that increasing DBI levels suffices to prevent anorexia induced by chronic restraint stress or chemotherapy with cisplatin, doxorubicin or paclitaxel in mice. At the mechanistic level, DBI administration acts through GABRA outside of the central nervous system and reduces the plasma levels of anorexigenic factors such as GDF15 (growth differentiation factor 15) and LCN2 (lipocalin 2), as well as anorexigenic signaling via the LCN2 receptor MC4R (melanocortin 4 receptor) in the hypothalamus. Accordingly, DBI supplementation stimulates food intake and normalizes whole body weight, body composition and metabolism in mouse models of anorexia. This normalization extends to the liver transcriptome and metabolome. Altogether, it appears that enhancing DBI levels constitutes a promising strategy for combating anorexia. Show less

The actions of thyroid hormones (THs) in the central nervous system are relevant to food intake and energy expenditure. TH receptors exhibit high expression in brain areas modulating energy balance, including the arcuate, paraventricular (PVN), supraoptic, and ventromedial (VMH) hypothalamic nuclei. To examine the role of THs in the regulation of energy balance via action in specific hypothalamic nuclei of the adult mouse, we performed experiments of conditional inactivation of DIO3, the enzyme responsible for the clearance of THs, in the lateral hypothalamus (LH), and VMH and PVN hypothalamic nuclei. We accomplished DIO3 genetic inactivation via stereotaxic injection of the AAV-cre vector into adult mice homozygous for a "floxed" Dio3 allele. Dio3 inactivation in the LH and VMH of males or females did not result in significant changes in body weight 8 weeks after injection. However, inactivation of Dio3 in the PVN resulted in increased body weight (both fat mass and lean mass) and locomotor activity, and decreased hypothalamic Mc4r expression in male, but not female mice. However, PNV-specific Dio3 KO did not cause hyperphagia. These results suggest local TH action influences MC4R signaling and possibly other PVN-associated circuitries, with consequences for body composition and energy balance endpoints, but not for orexigenic pathways. They also support a regulatory role for PVN Dio3 in the central regulation of energy homeostasis in adult life. Show less

Functional melanocortin receptor (MCR) genes have been identified in the genomes of early chordates, e.g., the cyclostomata. Whether they appear in the most ancient chordates such as cephalochordate and urochordata, however, remains unclear due to missing genetic data. Herein, we studied five putative (from NCBI database), sequence-based predicted MCR-like receptors from urochordata and cephalochordate, including Show less

The melanocortin receptor 4 (MC4R) belongs to the melanocortin receptor family of G-protein coupled receptors and is a key switch in the leptin-melanocortin molecular axis that controls hunger and satiety. Brain-produced hormones such as α-melanocyte-stimulating hormone (agonist) and agouti-related peptide (inverse agonist) regulate the molecular communication of the MC4R axis but are promiscuous for melanocortin receptor subtypes and induce a wide array of biological effects. Here, we use a chimeric construct of conformation-selective, nanobody-based binding domain (a ConfoBody Cb80) and active state-stabilized MC4R-β2AR hybrid for efficient de novo discovery of a sequence diverse panel of MC4R-specific, potent and full agonistic nanobodies. We solve the active state MC4R structure in complex with the full agonistic nanobody pN162 at 3.4 Å resolution. The structure shows a distinct interaction with pN162 binding deeply in the orthosteric pocket. MC4R peptide agonists, such as the marketed setmelanotide, lack receptor selectivity and show off-target effects. In contrast, the agonistic nanobody is highly specific and hence can be a more suitable agent for anti-obesity therapeutic intervention via MC4R. Show less

The Coastal Creole pigs in Argentina are predominantly found in the wild and can trace their lineage directly back to the Iberian breeds introduced by Spanish colonizers. They currently stand as the sole Creole breed in the country recognized by the FAO. However, there exists a dearth of studies assessing their genetic potential within the swine industry. Therefore, this study aimed to genetically characterize the meat quality of Coastal Creole pigs based on seven single nucleotide polymorphisms (SNPs) within the Ryr1, PRKAG3, MC4R, H-FABP, and CAST genes. A total of N = 158 samples were collected from specimens distributed along the coastal region. Our findings revealed all loci to exhibit polymorphism, underscoring the population's remarkable genetic diversity. Furthermore, a higher frequency of alleles favorable for the PRKAG3 Show less

Enteroendocrine cells (EECs) produce over 20 gut hormones which contribute to intestinal physiology, nutrient metabolism and the regulation of food intake. The objective of this study was to generate a comprehensive transcriptomic map of mouse EECs from the stomach to the rectum. EECs were purified by flow-cytometry from the stomach, upper small intestine, lower small intestine, caecum and large intestine of NeuroD1-Cre mice, and analysed by single cell RNA sequencing. Regional datasets were analysed bioinformatically and combined into a large cluster map. Findings were validated by L-cell calcium imaging and measurements of CCK secretion in vitro. 20,006 EECs across the full gastrointestinal tract could be subdivided based on their full transcriptome into 10 major clusters, each exhibiting a different pattern of gut hormone expression. EECs from the stomach were largely distinct from those found more distally, even when expressing the same hormone. Cell clustering was also observed when performed only using genes related to GPCR cell signalling, revealing GPCRs predominating in different EEC populations. Mc4r was expressed in 55% of Cck-expressing cells in the upper small intestine, where MC4R agonism was found to stimulate CCK release in primary cultures. Many individual EECs expressed more than one hormone as well as machinery for activation by multiple nutrients, which was supported by the finding that the majority of L-cells exhibited calcium responses to multiple stimuli. This comprehensive transcriptomic map of mouse EECs reveals patterns of GPCR and hormone co-expression that should be helpful in predicting the effects of nutritional and pharmacological stimuli on EECs from different regions of the gut. The finding that MC4R agonism stimulates CCK secretion adds to our understanding of the melanocortin system. Show less

Habits are familiar behaviors triggered by cues, not outcome predictability, and are insensitive to changes in the environment. They are adaptive under many circumstances but can be considered antecedent to compulsions and intrusive thoughts that drive persistent, potentially maladaptive behavior. Whether compulsive-like and habit-like behaviors share neural substrates is still being determined. Here, we investigated mice bred to display inflexible reward-seeking behaviors that are insensitive to action consequences. We found that these mice demonstrate habitual response biases and compulsive-like grooming behavior that was reversible by fluoxetine and ketamine. They also suffer dendritic spine attrition on excitatory neurons in the orbitofrontal cortex (OFC). Nevertheless, synaptic melanocortin 4 receptor (MC4R), a factor implicated in compulsive behavior, is preserved, leading to the hypothesis that Mc4r+ OFC neurons may drive aberrant behaviors. Repeated chemogenetic stimulation of Mc4r+ OFC neurons triggered compulsive and not inflexible or habitual response biases in otherwise typical mice. Thus, Mc4r+ neurons within the OFC appear to drive compulsive-like behavior that is dissociable from habitual behavior. Understanding which neuron populations trigger distinct behaviors may advance efforts to mitigate harmful compulsions. Show less

The skeleton is traditionally known for its structural support, organ protection, movement, and maintenance of mineral homeostasis. Over the last 10 years, bone has emerged as an endocrine organ with diverse physiological functions. The two key molecules in this context are fibroblast growth factor 23 (FGF23), secreted by osteocytes, and osteocalcin, a hormone produced by osteoblasts. FGF23 affects mineral homeostasis through its actions on the kidneys, and osteocalcin has beneficial effects in improving glucose homeostasis, muscle function, brain development, cognition, and male fertility. In addition, another osteoblast-derived hormone, lipocalin 2 (LCN2) has emerged into the researchers' field of vision. In this review, we mainly focus on LCN2's role in appetite regulation and glucose metabolism and also briefly introduce its effects in other pathophysiological conditions, such as nonalcoholic fatty liver disease, sarcopenic obesity, and cancer-induced cachexia. Show less

Phoenixin (PNX) is a conserved secreted peptide that was identified 10 years ago with numerous studies published on its pleiotropic functions. PNX is associated with estrous cycle length, protection from a high-fat diet, and reduction of anxiety behavior. However, no study had yet evaluated the impact of deleting PNX in the whole animal. We sought to evaluate a mouse model lacking the PNX parent gene, small integral membrane protein 20 (Smim20), and the resulting effect on reproduction, energy homeostasis, and anxiety. We found that the Smim20 knockout mice had normal fertility and estrous cycle lengths. Consistent with normal fertility, the hypothalamii of the knockout mice showed no changes in the levels of reproduction-related genes, but the male mice had some changes in energy homeostasis-related genes, such as melanocortin receptor 4 (Mc4r). When placed on a high-fat diet, the wildtype and knockout mice responded similarly, but the male heterozygous mice gained slightly less weight. When placed in an open field test box, the female knockout mice traveled less distance in the outer zone, indicating alterations in anxiety or locomotor behavior. In summary, the homozygous knockout of PNX did not alter fertility and modestly alters a few neuroendocrine genes in response to a high-fat diet, especially in the female mice. However, it altered the behavior of mice in an open field test. PNX therefore may not be crucial for reproductive function or weight, however, we cannot rule out possible compensatory mechanisms in the knockout model. Understanding the role of PNX in physiology may ultimately lead to an enhanced understanding of neuroendocrine mechanisms involving this enigmatic peptide. Show less

Bariatric surgery (BS) is considered the most effective intervention for patients with severe obesity and is used to maintain long-term weight loss and glycemic control. The aim of this study was to analyze the effects of genotypes and haplotypes of the fat mass and obesity-associated ( Show less

Heat stress (HS) is a global serious issue in the poultry industry with numerous adverse effects, including increased stress, depressed feed intake (FI), poor growth performance and higher mortality. Herbal adaptogens, plant extracts considered as stress response modifiers, are metabolic regulators that improve an organism's ability to adapt to and minimize damage from environmental stresses. Previously, we showed that herbal adaptogen supplementation increased FI and body weight (BW) of broiler (meat-type) chickens reared under HS conditions. Therefore, we hypothesized that these effects may be mediated through modulation of hypothalamic feeding-related neuropeptides. Male Cobb 500 chicks were reared in 12 environmental chambers with three diets: a corn-soybean-based diet (C) and two herbal adaptogen-supplemented diets at 500 g/1000 kg (NR-PHY-500) and 1 kg/1000 kg (NR-PHY-1000). Broilers in 9 chambers were exposed to chronic cyclic HS (35 °C for 8 h/day) from d29 to d42, while 3 chambers were maintained at 24 °C (thermoneutral, TN) for all 42 days. Hypothalamic samples were collected on d42 from each group, both before the onset of HS (Pre-HS) that day and after 3 h of HS (post-HS). Hypothalamic expressions of neuropeptide Y (NPY) receptors Y4 and Y7, Corticotropin-releasing hormone (CRH), orexin receptor 1 (ORXR1), melanocortin receptors (MC1R, MC4R, and MC5R), visfatin and neurosecretory protein GL (NPGL) genes were significantly upregulated by adaptogen supplementation. The hypothalamic expression of MC2R was affect by period, with a significant upregulation during post-HS phase. There was a significant period by treatment interaction for hypothalamic orexin and adiponectin expression. The hypothalamic expression of NPY, Y1, Y2, Y5, Y6, proopiomelanocortin (POMC), cocaine and amphetamine regulated transcript (CART), agouti-related peptide (AgRP), ORXR2, AdipR1/2, MC3R, and ghrelin was not affected by diet supplementation nor by HS exposure. In conclusion, these findings suggest that in-feed supplementation of adaptogen might improve FI and growth via modulation of hypothalamic feeding-related neuropeptides in heat-stressed broilers. Show less

To investigate the association of polymorphisms in SEC16B rs633715, DNAJC27 rs713586, FTO rs11642015 and MC4R rs6567160 with overweight and obesity in Han Chinese preschool children. A total of 749 Han Chinese preschool children from Henan and Guizhou Province of Long-term Health Effects Assessment Project of Infants and Toddlers Nutritional Pack were selected for the study and divided into an overweight and obese group and a normal control group in 2022. rs633715, rs713586, rs11642015 and rs6567160 were genotyped using Kompetitive allele-specific PCR(KASP) technology. The distribution of genotypic polymorphisms was compared using the χ~2 test. The association between the four loci and overweight and obesity in preschool children was analyzed using a multifactorial logistic regression model. The statistical analysis revealed a significant disparity(P<0.05) in the distribution of genotypic polymorphisms of rs633715 and rs6567160 among preschoolers in Henan and Guizhou Province. CC heterozygous mutant and recessive models at rs633715 locus were associated with susceptibility to overweight and obesity in preschool children [OR and 95% CI 2.915(1.163-7.305), and 2.997(1.226-7.323), respectively, both P<0.05]. TC heterozygous mutant and dominant models at rs713586 locus were also associated susceptibility to overweight and obesity in preschool children(OR and 95% CI were 2.362(1.054-5.289)and 2.362(1.054-5.289), respectively, both P<0.05). rs11642015 and rs6567160 loci were not associated with susceptibility to overweight and obesity in preschool children(P>0.05). The result of the analysis of the cumulative effect of rs633715 and rs713586 showed that the number of genotypes carrying the risk genotype was positively associated with the risk of overweight and obesity in preschool children(P₍trend)<0.01). Among Han Chinese preschool children, SEC16B rs633715 and DNAJC27 rs713586 were associated with susceptibility to overweight and obesity in preschool children. Moreover, rs633715 and rs713586 had a cumulative effect on susceptibility to overweight and obesity in preschool children, the number of risk genotypes carried was positively associated with childhood overweight and obesity risk. Show less

The melanocortin-4 receptor (MC4R) plays an important role in body weight regulation. Pathogenic MC4R variants are the most common cause of monogenic obesity. We have identified 17 MC4R variants in adult and pediatric patients with obesity. Here we aimed to functionally characterize these variants by analyzing 4 different aspects of MC4R signaling. In addition, we aimed to analyze the effect of setmelanotide, a potent MC4R agonist, on these MC4R variants. Cell surface expression and α-melanocyte stimulating hormone (α-MSH)- or setmelanotide-induced cAMP response, β-arrestin-2 recruitment, and ERK activation were measured in cells expressing either wild type or variant MC4R. We found a large heterogeneity in the function of these variants. We identified variants with a loss of response for all studied MC4R signaling, variants with no cAMP accumulation or ERK activation but normal β-arrestin-2 recruitment, and variants with normal cAMP accumulation and ERK activation but decreased β-arrestin-2 recruitment, indicating disrupted desensitization and signaling mechanisms. Setmelanotide displayed a greater potency and similar efficacy as α-MSH and induced significantly increased maximal cAMP responses of several variants compared to α-MSH. Despite the heterogeneity in functional response, there was no apparent difference in the obesity phenotype in our patients. We show that these obesity-associated MC4R variants affect MC4R signaling differently yet lead to a comparable clinical phenotype. Our results demonstrate the clinical importance of assessing the effect of MC4R variants on a range of molecular signaling mechanisms to determine their association with obesity, which may aid in improving personalized treatment. Show less