Melanocortin receptor-4 (MC4R) belongs to the G protein-coupled receptor family, characterized by a classical structure of seven transmembrane domains (7TMD). They play an important role in food intak Show more
Melanocortin receptor-4 (MC4R) belongs to the G protein-coupled receptor family, characterized by a classical structure of seven transmembrane domains (7TMD). They play an important role in food intake and weight regulation. In the present study, we identified melanocortin-4-receptor-like (caMC4RL) mutants of goldfish from the Qian River in the Qin Ling region and characterized their functional properties, including the constitutive activities of the mutants, ligand-induced cAMP and ERK1/2 accumulation, and AMPK activation. The results show that six caMC4RL mutants were identified in goldfish from the Qian River in the Qin Ling region, and are located in the conserved position of the Cyprinidae MC4Rs. The mutations (E57K, P296S, and R302T/K) result in the loss of Gs signaling function. The mutations (P296 and R302T/K) exhibited biased signaling in response to ACTH stimulation in the MAPK/ERK pathway. In addition, the E57K mutant may play a role in weight regulation and could serve as molecular markers for molecular breeding. These data will provide fundamental information for functional studies of teleost GPCR mutants and MC4R isoforms. Show less
Childhood obesity is a global concern and has both nutritional and genetic causative factors. One of the most common monogenic causes of obesity is heterozygous mutations in the Melanocortin 4 recepto Show more
Childhood obesity is a global concern and has both nutritional and genetic causative factors. One of the most common monogenic causes of obesity is heterozygous mutations in the Melanocortin 4 receptor (MC4R), which are found in 5.7-8.6% of individuals with early-onset obesity. We report, the effect of semaglutide, a long-acting glucagon-like peptide (GLP-1) analogue, in the treatment of severe obesity in an adolescent boy with a heterozygous mutation in MC4R. A 13-year-old boy with a history of excessive weight gain since infancy was referred to the specialised weight management team. He was born at full term with a birth weight of 3.57 kg (50th centile), but his weight consistently exceeded the 99.6th percentile after the age of 1 year. At the age of 5 years, he was diagnosed with autism spectrum disorder (ASD). Diagnostic investigations revealed insulin resistance and dyslipidaemia, while genetic testing confirmed a heterozygous mutation in MC4R (E61K), inherited from his mother. Managing his condition was challenging due to his rapid weight gain, needle phobia, and behavioural difficulties. Despite intense multidisciplinary lifestyle interventions, he continued to gain weight, reaching a peak weight of 187.5 kg (+16.65 standard deviation score [SDS]), body mass index (BMI) of 56.9 kg/m2 (+4.19 SDS), and body fat of 63.9% at the age of 13 years. Due to severe ASD and needle phobia, he was not keen on daily GLP-1 injections. He was commenced on semaglutide subcutaneous injection at a dose of 0.25 mg weekly, gradually increasing to the maximum dose of 1 mg weekly. Over the course of 12 weeks, his BMI decreased to 52.2 kg/m2 (+4.08 SDS) and weight dropped to 176.8 kg (+14.76 SDS, body fat: 52.7%). At the 3-month and 12-month reviews post-treatment, he achieved weight loss of 5.7% and 11%, respectively. The quality of life questionnaire showed improved scores from 35.95 to 60.36 at 12-month review, indicating enhanced well-being. The continuous glucose monitor demonstrated an improvement in time in range. Semaglutide was approved by the US Food and Drug Administration (FDA) for weight management in adolescents aged 12 years and above in December 2022. A recent case series underscored the benefits of therapy with liraglutide, a short-acting GLP-1 analogue, in rare genetic cases of early-onset obesity. To our knowledge, this is the first case report to highlight the efficacy and safety of semaglutide in an adolescent with heterozygous MC4R mutation. Semaglutide could be a potential treatment option for monogenic obesity and will benefit from further research. Show less
The melanocortin receptors are a class of centrally and peripherally expressed G protein-coupled receptors, of which the MC3R and MC4R subtypes are implicated in the regulation of appetite and energy Show more
The melanocortin receptors are a class of centrally and peripherally expressed G protein-coupled receptors, of which the MC3R and MC4R subtypes are implicated in the regulation of appetite and energy homeostasis and can serve as potential therapeutic targets for disorders such as obesity and cachexia. An unbiased high-throughput mixture-based library screen was implemented to identify novel ligands with an emphasis on the identification of nanomolar-potent agonists of the mouse melanocortin-3 receptor. This screen yielded the discovery of an N-branched tricyclic guanidine scaffold (TPI2408) that contained three nanomolar potent mMC3R agonists and additional compounds that possessed antagonism for the mMC4R. The antagonist character of this scaffold library at the mMC4R was confirmed by a follow-up positional scanning antagonist screen. Additionally, molecular dynamics simulations herein provide mechanistic insight into the polypharmacological characteristics of melanocortin receptors. The disclosed materials have the potential to serve as important tools and SAR scaffolds in the study of melanocortin receptor function. Show less
Communication of gut hormones with the central nervous system is important to regulate systemic glucose homeostasis, but the precise underlying mechanism involved remain little understood. Nesfatin-1, Show more
Communication of gut hormones with the central nervous system is important to regulate systemic glucose homeostasis, but the precise underlying mechanism involved remain little understood. Nesfatin-1, encoded by nucleobindin-2 (NUCB2), a potent anorexigenic peptide hormone, was found to be released from the gastrointestinal tract, but its specific function in this context remains unclear. Herein, we found that gut nesfatin-1 can sense nutrients such as glucose and lipids and subsequently decreases hepatic glucose production. Nesfatin-1 infusion in the small intestine of NUCB2-knockout rats reduced hepatic glucose production via a gut - brain - liver circuit. Mechanistically, NUCB2/nesfatin-1 interacted directly with melanocortin 4 receptor (MC4R) through its H-F-R domain and increased cyclic adenosine monophosphate (cAMP) levels and glucagon-like peptide 1 (GLP-1) secretion in the intestinal epithelium, thus inhibiting hepatic glucose production. The intestinal nesfatin-1 -MC4R-cAMP-GLP-1 pathway and systemic gut-brain communication are required for nesfatin-1 - mediated regulation of liver energy metabolism. These findings reveal a novel mechanism of hepatic glucose production control by gut hormones through the central nervous system. Show less
To explore the prevalence and associated factors of obesity in Tibetan adults in Qinghai, China, and to determine the association between the FTO (rs1121980 and rs17817449) and MC4R gene (rs17782313 a Show more
To explore the prevalence and associated factors of obesity in Tibetan adults in Qinghai, China, and to determine the association between the FTO (rs1121980 and rs17817449) and MC4R gene (rs17782313 and rs12970134) polymorphisms with obesity. A cross-sectional survey was conducted in 2015 in Qinghai to selected Tibetan adults aged 20 to 80 years. Prevalence of obesity (BMI ≥ 28 kg/m A total of 1741 Tibetan adults were enrolled. The age- and sex- standardized prevalence of obesity and overweight was 18.09% and 31.71%, respectively. Male sex, older age, heavy level of leisure-time exercise, current smoke, and heavy level of occupational physical activity were associated with both obesity and overweight. MC4R gene polymorphisms were associated with obesity in Tibetan adults. No significant gene-environment interaction was detected. The prevalence of obesity and overweight in Tibetan adults was high. Both environmental and genetic factors contributed to the obesity prevalent. Show less
Individuals with obesity caused by biallelic pathogenic LEPR (leptin receptor) variants can benefit from setmelanotide, the novel MC4R agonist. An ongoing phase 3 clinical trial (NCT05093634) includes Show more
Individuals with obesity caused by biallelic pathogenic LEPR (leptin receptor) variants can benefit from setmelanotide, the novel MC4R agonist. An ongoing phase 3 clinical trial (NCT05093634) includes individuals with obesity who carry a heterozygous LEPR variant, although the obesogenic impact of these variants remains incompletely evaluated. The aim of this study was to functionally assess heterozygous variants in LEPR and to evaluate their effect on obesity. We sequenced LEPR in ∼10,000 participants from the French RaDiO study. We found 86 rare heterozygous variants. Each identified variant was then investigated in vitro using luciferase and western blot assays. Using the criteria of the American College of Medical Genetics and Genomics (ACMG), including the strong criterion related to functional assays, we found 12 pathogenic LEPR variants. Most heterozygotes did not present with obesity, and we found no association between these pathogenic variants and body mass index (BMI). This lack of association between pathogenic LEPR variants and obesity risk or BMI was confirmed using exome data from 200,000 individuals in the UK Biobank. In the literature, among 55 reported heterozygotes for of a rare pathogenic LEPR variant, only 27% had obesity. In conclusion, monoallelic pathogenic LEPR variants were functionally tested, and they do not elevate the risk of obesity or BMI levels. This raises questions about the use of setmelanotide, a costly drug with potential side effects, based solely on the presence of a heterozygous LEPR variant. Show less
The central melanocortin system links nutrition to energy expenditure, with melanocortin-4 receptor (MC4R) controlling appetite and food intake, and MC3R regulating timing of sexual maturation, rate o Show more
The central melanocortin system links nutrition to energy expenditure, with melanocortin-4 receptor (MC4R) controlling appetite and food intake, and MC3R regulating timing of sexual maturation, rate of linear growth and lean mass accumulation. Melanocortin-2 receptor accessory protein-2 (MRAP2) is a single transmembrane protein that interacts with MC4R to potentiate it's signalling, and human mutations in MRAP2 cause obesity. Previous studies have been unable to consistently show whether MRAP2 affects MC3R activity. Here we used single-molecule pull-down (SiMPull) to confirm that MC3R and MRAP2 interact in HEK293 cells. Analysis of fluorescent photobleaching steps showed that MC3R and MRAP2 readily form heterodimers most commonly with a 1:1 stoichiometry. Human single-nucleus and spatial transcriptomics show MRAP2 is co-expressed with MC3R in hypothalamic neurons with important roles in energy homeostasis and appetite control. Functional analyses showed MRAP2 enhances MC3R cAMP signalling, impairs β-arrestin recruitment, and reduces internalization in HEK293 cells. Structural homology models revealed putative interactions between the two proteins and alanine mutagenesis of five MRAP2 and three MC3R transmembrane residues significantly reduced MRAP2 effects on MC3R signalling. Finally, we showed genetic variants in MRAP2 that have been identified in individuals that are overweight or obese prevent MRAP2's enhancement of MC3R-driven signalling. Thus, these studies reveal MRAP2 as an important regulator of MC3R function and provide further evidence for the crucial role of MRAP2 in energy homeostasis. Show less
Genotype analysis was done for 45 samples. The research results were obtained with the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The 1,200-bp PCR product wa Show more
Genotype analysis was done for 45 samples. The research results were obtained with the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The 1,200-bp PCR product was cut with Upon analyzing the data, it was found that 37.8% ( After analysis of the study results, a statistically significant difference was observed between cats with DM and clinically healthy cats in the comparison of their BCS ( Show less
The role of leptin in regulating cardiac function is still controversial with conflicting results in clinical and preclinical studies. However, most previous studies have not considered leptin's power Show more
The role of leptin in regulating cardiac function is still controversial with conflicting results in clinical and preclinical studies. However, most previous studies have not considered leptin's powerful cardiac effects that are mediated via activation of central nervous system (CNS) leptin receptors (LepRs) which, in turn, elicit major improvements in cardiac metabolism. In this review, we focus mainly on the role of leptin in regulating cardiac function via its CNS LepRs and downstream signaling pathways, such as the brain melanocortin system. Studies from our laboratory showed that CNS LepR activation, without raising plasma leptin levels, has remarkable beneficial effects on cardiac metabolism and function that protect the heart during pathological conditions, including heart failure (HF) induced by myocardial infarction (MI). These cardioprotective effects of leptin appear to be mediated by stimulation of CNS proopiomelanocortin neurons and subsequent activation of melanocortin 4 receptors (MC4R) in the brain. Chronic activation of the brain leptin-melanocortin pathway improves cardiac function and metabolism following myocardial infarction. However, the mechanism underlying this brain-heart crosstalk remains unclear and may have important implications for the development of new therapies for MI and HF. Show less
Polycystic ovary syndrome (PCOS) is the most common endocrine disorder occurring in women of reproductive age. The disease is caused by a complex interplay of genetic and environmental factors includi Show more
Polycystic ovary syndrome (PCOS) is the most common endocrine disorder occurring in women of reproductive age. The disease is caused by a complex interplay of genetic and environmental factors including genes encoding components of the hypothalamic-pituitary-adrenal (HPA) axis. We have recently reported the association of melanocortin receptor genes (MC1R, MC2R, MC3R, MC4R, and MC5R) with the risk of type 2 diabetes (T2D) and/or major depressive disorder (MDD). The latter 2 disorders are comorbid with PCOS. In this study, we used microarray to test 12 single nucleotide polymorphisms (SNPs) in the MC1R gene, 10 SNPs in the MC2R gene, 5 SNPs in the MC3R gene, 6 SNPs in the MC4R gene, and 4 SNPs in the MC5R gene in 212 original Italian families with PCOS. We identified 1 SNP in MC1R, 1 SNP in MC2R, 2 SNPs in MC3R, and 2 SNPs in MC5R significantly linked and/or associated to/with the risk of PCOS in Italian families. This is the first study to report the novel implication of melanocortin receptor genes (MC1R, MC2R, and MC5R) in PCOS. MC3R and MC4R were previously reported in PCOS. However, functional studies are needed to validate these results. Show less
Cyclic adenosine monophosphate-response element-binding protein-1-regulated transcription coactivator-1 (CRTC1), a cytoplasmic coactivator that translocates to the nucleus in response to cAMP, is asso Show more
Cyclic adenosine monophosphate-response element-binding protein-1-regulated transcription coactivator-1 (CRTC1), a cytoplasmic coactivator that translocates to the nucleus in response to cAMP, is associated with obesity. We previously reported that Show less
Postnatal hippocampal neurogenesis is essential for learning and memory. Hippocampal neural precursor cells (NPCs) can be induced to proliferate and differentiate into either glial cells or dentate gr Show more
Postnatal hippocampal neurogenesis is essential for learning and memory. Hippocampal neural precursor cells (NPCs) can be induced to proliferate and differentiate into either glial cells or dentate granule cells. Notably, hippocampal neurogenesis decreases dramatically with age, partly due to a reduction in the NPC pool and a decrease in their proliferative activity. Alpha-melanocyte-stimulating hormone (α-MSH) improves learning, memory, neuronal survival and plasticity. Here, we used postnatally-isolated hippocampal NPCs from Wistar rat pups (male and female combined) to determine the role of the melanocortin analog [Nle Show less
Trends in the development of genetic markers for the purposes of genomic and marker-assisted selection primarily focus on identifying causative polymorphisms. Using these polymorphisms as markers enab Show more
Trends in the development of genetic markers for the purposes of genomic and marker-assisted selection primarily focus on identifying causative polymorphisms. Using these polymorphisms as markers enables a more accurate association between genotype and phenotype. Bioinformatic analysis allows calculating the impact of missense polymorphisms on the structural and functional characteristics of proteins, which makes it promising for identifying causative polymorphisms. In this study, a bioinformatic approach is applied to evaluate and differentiate polymorphisms based on their causality in genes that affect the production traits of pigs and cows, which are two important livestock species. The influence of both known causative and candidate missense polymorphisms in the MC4R, NR6A1, PRKAG3, RYR1, and SYNGR2 genes of pigs, as well as the ABCG2, DGAT1, GHR, and MSTN genes of cows, was assessed. The study included an evaluation of the effect of polymorphisms on protein functions, considering the evolutionary and physicochemical characteristics of amino acids at polymorphic sites. Additionally, it examined the impact of polymorphisms on the stability of tertiary protein structures, including changes in folding, binding of protein monomers, and interaction with ligands. The comprehensive bioinformatic analysis used in this study enables the differentiation of polymorphisms into neutral, where both amino acids in the polymorphic site do not significantly affect the structure and function of the protein, and causative, where one of the amino acids significantly impacts the protein's properties. This approach can be employed in future research to screen extensive sets of polymorphisms in animal genomes, identifying the most promising polymorphisms for further investigation in association studies. Show less
Obesity is increasingly prevalent worldwide, with genetic factors contributing to its development. The hypothalamic leptin-melanocortin pathway is central to the regulation of appetite and weight; lep Show more
Obesity is increasingly prevalent worldwide, with genetic factors contributing to its development. The hypothalamic leptin-melanocortin pathway is central to the regulation of appetite and weight; leptin activates the proopiomelanocortin neurons, leading to the production of melanocortin peptides; these in turn act on melanocortin 4 receptors (MC4R) which suppress appetite and increase energy expenditure. MC4R mutations are responsible for syndromic and non-syndromic obesity. These mutations are classified based on their impact on the receptor's life cycle: Show less
Lutein (L) and zeaxanthin (Z) are involved in visual function and could prevent age-related macular degeneration and chronic diseases and improve cognitive performances. Adipose tissue is the main sto Show more
Lutein (L) and zeaxanthin (Z) are involved in visual function and could prevent age-related macular degeneration and chronic diseases and improve cognitive performances. Adipose tissue is the main storage site for these xanthophylls (Xanth). The factors affecting their concentrations in this tissue remain poorly understood but in animal models, genetic variations in apolipoprotein E and β-carotene oxygenase 2 have been associated with adipose tissue L concentration. Therefore, the aims of this study were to better characterize the interindividual variability of adipose tissue Xanth concentration and to identify single nucleotide polymorphisms (SNPs) associated with it. Periumbilical subcutaneous adipose tissue samples were collected on 6 occasions in 42 healthy adult males and L and Z concentrations were measured by HPLC. Participants had their whole genome genotyped and the associations of 3589 SNPs in 49 candidate genes with the concentrations of L and Z were measured. Mean L and Z concentrations were 281 ± 27 and 150 ± 14 nmol g Show less
The most recent version of ClinVar was utilized to filter variants of the MC4R gene based on location, condition, and clinical significance with the goal of obtaining benign and disease-associated var Show more
The most recent version of ClinVar was utilized to filter variants of the MC4R gene based on location, condition, and clinical significance with the goal of obtaining benign and disease-associated variants of the MC4R gene. MC4R gene variants can lead to dysregulation of energy expenditure and appetite control, which prompted this study to delineate the distinctive features of MC4R gene variants submitted to the ClinVar repository regarding their association with obesity and related phenotypes. A thorough search was conducted in the ClinVar repository for clinically significant MC4R variants through the utilization of the gene name MC4R[gene] and MeSH terms "MC4R[gene]" and "single gene"[properties]" in the search box. Leading to the identification of clinically significant genetic variants associated with obesity. Utilizing the ClinVar clinical significance ranking system, the MC4R variants were categorized into six groups based on ClinVar/ClinGen's ranking system: pathogenic (P), likely pathogenic (LP), variant of uncertain significance (VUS), benign (B), likely benign (LB), and conflicting classifications (CC). A total of 103 pathogenic variants were observed. These variants have different clinical significance that are associated with monogenic obesity, monogenic diabetes, and body mass index quantitative traits. It was observed that over 80% of the mutations were single nucleotide variants, with nearly half being missense mutations spread throughout the topological and transmembrane domains. Furthermore, TM7 had the highest number of single nucleotide missense mutations. Further analysis of the relationships between monogenic obesity and diabetes requires additional investigation to discover the underlying causes of these conditions. The study findings imply that mutations in MC4R's topological and transmembrane regions may significantly influence receptor activation and signaling. As more MC4R variants are discovered and their correlation with obesity is established, there is potential to definitively establish a strong connection between MC4R pathogenic variants and the development of obesity. Show less
Obesity, by any standard, is a global health crisis. Both genetic and dietary contributions to the development and maintenance of obesity were integral factors of our experimental design. As mutations Show more
Obesity, by any standard, is a global health crisis. Both genetic and dietary contributions to the development and maintenance of obesity were integral factors of our experimental design. As mutations of the melanocortin 4 receptors (MC4R) are the leading monogenetic cause of obesity, MC4R haploinsufficient rats were fed a range of dietary fat (0-12 %) in a longitudinal design. Physiological and motivational assessments were performed using a locomotor task, a 5-choice sucrose preference task, an operant task with fixed and progressive ratios, as well as a distraction operant task. Dendritic spine morphology of medium spiny neurons (MSNs) of the nucleus accumbens (NAc), cells with ample D1 and D2 receptors, was also assessed. The percentage of lipid deposits in the liver of each rat was also analyzed using the Area Fraction Fractionator probe for stereological measurements. MC4R haploinsufficiency resulted in a phenotypic resemblance for adult-onset obesity that was exacerbated by the consumption of a high-fat diet. Results from the operant tasks indicate that motivational deficits due to MC4R haploinsufficiency were apparent prior to the onset of obesity and exacerbated by dietary fat consumption after obesity was well established. Moreover, MSN morphology shifted to longer spines with smaller head diameters for the MC4R+/- animals under the high-fat diet, suggesting a potential mechanism for the dysregulation of motivation to work for food. Increasing our knowledge of the neural circuitry/mechanisms responsible for the rewarding properties of food has significant implications for understanding energy balance and the development of obesity. Show less
The prevalence of obesity is increasing worldwide, affecting both children and adults. This obesity epidemic is mostly driven by an increase in energy intake (abundance of highly palatable energy-dens Show more
The prevalence of obesity is increasing worldwide, affecting both children and adults. This obesity epidemic is mostly driven by an increase in energy intake (abundance of highly palatable energy-dense food and drinks) and to a lesser degree a decrease in energy expenditure (sedentary lifestyle). A small proportion of individuals with obesity are affected by genetic forms of obesity, which often relate to mutations in the leptin-melanocortin pathway or are part of syndromes such as the Bardet-Biedl syndrome. These rare forms of obesity have provided valuable insights into the genetic architecture of obesity. Recent advances in understanding the molecular mechanisms that control appetite, hunger, and satiety have led to the development of drugs that can override genetic defects, enabling precision treatment. Leptin deficiency is uniquely treated with recombinant human metreleptin, while those with LEPR, PCSK1, or POMC deficiency can now be treated with the MC4R agonist setmelanotide. This review highlights the most frequent monogenic and syndromic forms of obesity, and the future outlook of precision treatment for these conditions. Show less
Most antipsychotic drugs (APDs) induce hyperphagia and weight gain. However, the neural mechanisms are poorly understood, partly due to challenges replicating their metabolic effects in rodents. Here, Show more
Most antipsychotic drugs (APDs) induce hyperphagia and weight gain. However, the neural mechanisms are poorly understood, partly due to challenges replicating their metabolic effects in rodents. Here, we report a new mouse model that recapitulates overeating induced by clozapine, a widely prescribed APD. Our study shows that clozapine boosts food intake by inhibiting melanocortin 4 receptor (MC4R) expressing neurons in the paraventricular nucleus of the hypothalamus. Interestingly, neither clozapine nor risperidone, another commonly used APD, affects receptor-ligand binding or the canonical Gαs signaling of MC4R. Instead, they inhibit neuronal activity by enhancing the coupling between MC4R and Kir7.1, leading to the open state of the inwardly rectifying potassium channel. Deletion of Show less
Many pharmacological treatments are considered effective in the treatment of panic disorder (PD), however, about 20 to 40% of the patients have treatment-resistant PD. Pharmacogenetics could explain w Show more
Many pharmacological treatments are considered effective in the treatment of panic disorder (PD), however, about 20 to 40% of the patients have treatment-resistant PD. Pharmacogenetics could explain why some patients are treatment-resistant. Our objective was to gather preliminary data on the clinical usefulness of pharmacogenetic testing in this disorder. Twenty patients with treatment-resistant PD were included in this observational study and submitted to commercial pharmacogenetic testing. Testing panel included gene polymorphisms related to CYP, genes In 30% of the patients, the tests indicated reduced chance of response to the prescribed drug, while they indicated very low serum levels of the prescribed drug in 20% of the subjects. The pharmacogenetic tests predicted reduction of MTHFR enzyme activity in 74% of the patients. ABCB1 gene alleles associated to drug resistance were found in 90% of the samples. Commercial pharmacogenetic testing failed to predict negative treatment outcome in most patients with PD. The association between treatment-resistance in PD and the genes CYP2C19, MTHFR and ABCB1 deserves further study. Show less
Gene-environment interaction studies are emerging as a promising tool to shed light on the reasons for the rapid increase in excess body weight (overweight and obesity). We aimed to investigate the in Show more
Gene-environment interaction studies are emerging as a promising tool to shed light on the reasons for the rapid increase in excess body weight (overweight and obesity). We aimed to investigate the influence of several polymorphisms on excess weight in Spanish children according to a short- and long-term exposure to bisphenols and parabens, combining individual approach with the joint effect of them. This case-control study included 144 controls and 98 cases children aged 3-12 years. Thirty SNPs in genes involved in obesity-related pathways, xenobiotic metabolism and hormone systems were genotyped using the GSA microchip technology and qPCRs with Taqman® probes. Levels of bisphenols and parabens in urine and hair were used to assess short- and long-term exposure, respectively, via UHPLC-MS/MS system. LEPR rs9436303 was identified as a relevant risk variant for excess weight (OR Show less
Hereditary defects in the function of the Kir7.1 in the retinal pigment epithelium are associated with the ocular diseases retinitis pigmentosa, Leber congenital amaurosis, and snowflake vitreal degen Show more
Hereditary defects in the function of the Kir7.1 in the retinal pigment epithelium are associated with the ocular diseases retinitis pigmentosa, Leber congenital amaurosis, and snowflake vitreal degeneration. Studies also suggest that Kir7.1 may be regulated by a GPCR, the melanocortin-4 receptor, in certain hypothalamic neurons. We present the first structures of human Kir7.1 and describe the conformational bias displayed by two pathogenic mutations, R162Q and E276A, to provide an explanation for the basis of disease and illuminate the gating pathway. We also demonstrate the structural basis for the blockade of the channel by a small molecule ML418 and demonstrate that channel blockade in vivo activates MC4R neurons in the paraventricular nucleus of the hypothalamus (PVH), inhibiting food intake and inducing weight loss. Preliminary purification, and structural and pharmacological characterization of an in tandem construct of MC4R and Kir7.1 suggests that the fusion protein forms a homotetrameric channel that retains regulation by liganded MC4R molecules. Show less
To explore the patterns of differentially expressed genes (DEGs) associated with different growth rates in rock carp (Procypris rabaudi), transcriptome sequencing was performed on the muscle, liver, a Show more
To explore the patterns of differentially expressed genes (DEGs) associated with different growth rates in rock carp (Procypris rabaudi), transcriptome sequencing was performed on the muscle, liver, and brain tissues of rock carp. Subsequently, bioinformatics analysis was conducted, and 2129, 1380, and 415 DEGs were identified in the muscle, liver, and brain tissues, respectively. GO enrichment and KEGG pathway analysis revealed that genes related to appetite regulation, protein degradation and digestion, lipid transport and metabolisms, and glycolysis/gluconeogenesis were upregulated in individuals with slower growth rates. Differential expression analysis identified 21 genes associated with feeding and metabolism across three tissues, including mc4r, npy, and npry in brain tissue; fatp, fabp, pparα, and apo in liver tissue; and prss, ctrl, and cela in muscle tissue. All these genes were upregulated in the slow-growing fish. Furthermore, weighted gene co-expression network analyses, including three modules (yellow, turquoise, and brown), significantly associated with growth. A network map that included these three modules enabled the identification of a series of hub genes, including rp13a, ube2o, h6pd, etc. These genes may be key candidate genes regulating the growth of rock carp. This study contributes to a deeper understanding of the growth control mechanism in rock carp and offers a scientific basis for efficient breeding and species improvement. 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 in Show more
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
Cyclic dipeptides (CDPs), known for their diverse biological activities, have potential therapeutic applications in mental and behavioral disorders (MBDs), particularly schizophrenia. This study explo Show more
Cyclic dipeptides (CDPs), known for their diverse biological activities, have potential therapeutic applications in mental and behavioral disorders (MBDs), particularly schizophrenia. This study explores the CDPs' therapeutic potential using bibliometric analysis, network pharmacology, molecular docking, and experimental verification, focusing on the interactions with the SIGMA1 receptor. A literature review over three decades utilizing the Web of Science Core Collection (WOSCC) was conducted to identify the emerging trends in CDPs research. A compound library was constructed from the PubChem database, and target prediction using SwissTargetPrediction revealed 800 potential protein targets. A compound-target network highlighted the key interactions with kinases, G protein-coupled receptors, and chromatin-modifying enzymes. Enrichment analysis revealed significant associations with schizophrenia and other MBDs. Schizophrenia-related targets among the potential protein targets were identified using the GEO database. Molecular docking results showed interactions of MC4R, OPRK1, SIGMA1, and CDK5R1 with various CDPs compounds, with SIGMA1 being especially noteworthy. Most CDPs exhibited lower binding energies than the control compounds NE-100 and duloxetine. Experimental validation demonstrated that CDPs such as Cyclo(Ala-Gln), Cyclo(Ala-His), and Cyclo(Val-Gly) exhibited IC Show less