Search Results (218)

Heat stress (HS) is a major environmental factor negatively impacting the reproductive performance of livestock. This study investigates the molecular mechanisms of heat stress on the hypothalamic–pituitary–ovarian (HPO) axis in Hu sheep. A heat-stressed animal model was established, and high-throughput RNA sequencing (RNA-seq) was employed to analyze gene expression in the hypothalamus, pituitary, and ovarian tissues of both control and heat-stressed groups. The results revealed significant changes in estrus behavior, hormone secretion, and reproductive health in heat-stressed sheep, with a shortened estrus duration, prolonged estrous cycles, and decreased levels of FSH, LH, E₂, and P4. A total of 520, 649, and 482 differentially expressed genes (DEGs) were identified in the hypothalamus, pituitary, and ovary, respectively. The DEGs were enriched in pathways related to hormone secretion, neurotransmission, cell proliferation, and immune response, with significant involvement of the p53 and cAMP signaling pathways. Tissue-specific responses to heat stress were observed, with distinct regulatory roles in each organ, including GPCR activity and cytokine signaling in the hypothalamus, calcium-regulated exocytosis in the pituitary, and cilium assembly and ATP binding in the ovary. Key genes such as SYN3, RPH3A, and IGFBP2 were identified as central to the coordinated regulation of the HPO axis. These findings provide new insights into the molecular basis of heat stress-induced impairments in reproductive function—manifested by altered estrous behavior, reduced hormone secretion (FSH, LH, E₂, and P4), and disrupted gene expression in the hypothalamic–pituitary–ovarian (HPO) axis—and offer potential targets for improving heat tolerance and reproductive regulation in sheep. Full article

Prenatal and postnatal skeletal muscle development in ruminants is coordinated by interactions between genetic, nutritional, epigenetic, and endocrine factors. This review focuses on the influence of maternal nutrition during gestation on fetal myogenesis, satellite cell dynamics, and myogenic regulatory factors expression, including MYF5, MYOD1, and MYOG. Studies in sheep and cattle indicate that nutrient restriction or overnutrition alters muscle fiber number, the cross-sectional area, and the transcriptional regulation of myogenic genes in offspring. Postnatally, muscle hypertrophy is primarily mediated by satellite cells, which are activated via PAX7, MYOD, and MYF5, and regulated through mechanisms such as CARM1-induced chromatin remodeling and miR-31-mediated mRNA expression. Hormonal signaling via the GH–IGF1 axis and thyroid hormones further modulate satellite cell proliferation and protein accretion. Genetic variants, such as myostatin mutations in Texel sheep and Belgian Blue cattle, enhance muscle mass but may compromise reproductive efficiency. Nutritional interventions, including the plane of nutrition, supplementation strategies, and environmental stressors such as heat and stocking density, significantly influence muscle fiber composition and carcass traits. This review provides a comprehensive overview of skeletal muscle programming in ruminants, tracing the developmental trajectory from progenitor cell differentiation to postnatal growth and maturation. These insights underscore the need for integrated approaches combining maternal diet optimization, molecular breeding, and precision livestock management to enhance muscle growth, meat quality, and production sustainability in ruminant systems. Full article

Per- and polyfluoroalkyl substances (PFASs) comprise a diverse array of synthetic chemicals that resist environmental degradation. They are increasingly recognised as endocrine-disrupting compounds (EDCs). These chemicals, found in non-stick cookware, food packaging, and industrial waste, accumulate in human tissues and fluids, raising substantial concerns regarding their impact on female reproductive health. Epidemiological studies have demonstrated associations between PFAS exposure and reduced fertility; nevertheless, the underlying molecular pathways remain inadequately understood. This narrative review investigates the multifaceted effects of PFASs on ovarian physiology, including its disruption of the hypothalamic–pituitary–ovarian (HPO) axis, alteration of anti-Müllerian hormone (AMH) levels, folliculogenesis, and gonadotropin receptor signalling. Significant attention is directed towards the emerging association between PFASs and polycystic ovarian syndrome (PCOS), wherein PFAS-induced hormonal disruption may exacerbate metabolic issues and elevated androgen levels. Furthermore, we analyse the current data regarding PFAS exposure in women undergoing treatment based on assisted reproductive technologies (ARTs), specifically in vitro fertilisation (IVF), highlighting possible associations with diminished oocyte quality, suboptimal embryo development, and implantation failure. We examine potential epigenetic and transgenerational alterations that may influence women’s reproductive capabilities over time. This study underscores the urgent need for further research and regulatory actions to tackle PFAS-related reproductive toxicity, particularly in vulnerable populations, such as women of reproductive age and those receiving fertility treatments. Full article

The hypothalamic-pituitary-adrenal (HPA) axis plays an important regulatory role in inflammatory responses to systemic or local infection in the host. A high-calorie diet, which can aggravate pediatric pneumonia and delay recovery, is intimately associated with HPA axis disorder; however, its underlying mechanisms remain unknown. This study examined whether the mechanism by which a high-calorie diet aggravates pneumonia is related to HPA axis disorder. In this study, juvenile rats were fed a high-calorie diet and/or nebulized with lipopolysaccharide (LPS) for model construction. Our data shows that a high-calorie diet increases interleukin-1 beta(IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) levels in lung tissues and aggravates LPS-induced inflammatory injury in the lungs of juvenile rats. Additionally, we found that a high-calorie diet decreases the expression level of serum adrenocorticotropic hormone (ACTH) and corticosterone (CORT) in juvenile rats with pneumonia, resulting in HPA axis disorder. Hypothalamus proteomics and Western blot results proved that a high-calorie diet upregulated the expression level of hypothalamus hypoxia-inducible factor-1 alpha (HIF-1α) in juvenile rats with pneumonia, and this mechanism is associated with reduced HIF-1α ubiquitination. We further observed that HPA axis disorder was significantly abated and inflammatory damage in rat lung tissues was significantly alleviated after in vivo HIF-1α pathway inhibition. This shows that pneumonia aggravation by a high-calorie diet is associated with interference in the HIF-1α-mediated HPA axis. A high-calorie diet boosts HIF-1α signaling in the hypothalamus and exacerbates LPS-induced pneumonia by disrupting the HPA axis. This sheds light on lung inflammation and strengthens the lung-brain connection. Full article

In women, gonadal hormones play a crucial regulatory role in body fat distribution and glucose–lipidic homeostasis, which are closely associated with the hepatic steatogenesis and intrahepatic inflammatory pathways. Accumulating evidence supports the idea that hepatic health is closely linked to endocrine ovarian function through hormonal, metabolic, and immunological communications, collectively known as the “ovary–liver axis”. This review presents the molecular mechanisms involved in sex hormone synthesis, metabolism, and signaling pathways along the ovary–liver axis, focusing on dysregulated mechanisms that may contribute to common disorders and, specifically to hepatic derangements in the context of altered ovarian function. Additionally, we analyzed epidemiological evidence supporting the ovary–liver axis, specifically examining meta-analytic studies exploring the connection between polycystic ovary syndrome and metabolic dysfunction-associated steatotic liver disease (MASLD). We also discuss studies linking hypogonadism with liver health, with a specific focus on Turner syndrome and MASLD. Furthermore, we explore the impact of menopause on liver health. Our integrated molecular and epidemiological approach identifies important clinical and public health implications, aiming to uncover potentially innovative interventions and effective strategies for managing disease progression. However, unexplored areas within the ovary–liver axis highlight the need for further research on causal pathways. Full article

Background: Duchenne muscular dystrophy (DMD) is a severe X-linked neuromuscular disorder caused by mutations in the DMD gene, leading to progressive muscle degeneration, loss of ambulation, and multi-systemic complications. Beyond its impact on mobility, DMD is associated with significant endocrine and metabolic dysfunctions that develop over time. Objective: To provide a comprehensive analysis of growth disturbances, endocrine dysfunctions, and metabolic complications in DMD including bone metabolism, considering the underlying mechanisms, clinical implications, and management strategies for daily clinical guidance. Methods: In this narrative review, an evaluation of the literature was conducted by searching the Medline database via the PubMed, Scopus, and Web of Science interfaces. Results: Growth retardation is a hallmark feature of DMD, with patients exhibiting significantly shorter stature compared to their healthy peers. This is exacerbated by long-term glucocorticoid therapy, which disrupts the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis and delays puberty. Obesity prevalence follows a biphasic trend, with increased risk in early disease stages due to reduced mobility and corticosteroid use, followed by a decline in body mass index (BMI) in later stages due to muscle wasting. Metabolic complications, including insulin resistance, altered lipid metabolism, and hepatic steatosis, further characterize disease burden. Osteoporosis and increased fracture risk, primarily due to reduced mechanical loading and glucocorticoid-induced bone resorption, are major concerns, needing early screening and intervention. The RANK/RANKL/OPG signaling pathway has emerged as a critical factor in bone deterioration, providing potential therapeutic targets for improving skeletal health. Conclusions: Growth and endocrine disorders in DMD are complex and multifactorial, requiring proactive monitoring and early intervention. Addressing these issues requires a multidisciplinary approach integrating endocrine, nutritional, and bone health management. Further research is essential to refine treatment strategies that mitigate growth and metabolic disturbances while preserving overall patient well-being. Full article

Idiopathic short stature (ISS) represents one of the most frequent yet enigmatic conditions in pediatric endocrinology. Traditionally defined by auxological parameters in the absence of identifiable causes, ISS has long served as a diagnosis of exclusion. However, with the advent of next-generation sequencing, our understanding of the etiological landscape has significantly evolved. Recent studies have revealed that many children previously labeled as idiopathic actually harbor monogenic variants in genes related to the growth hormone–insulin-like growth factor axis, extracellular matrix components, or growth plate signaling pathways. This review integrates auxological assessment with current knowledge on molecular diagnostics to propose a more accurate and individualized approach to short stature. We examine emerging genotype–phenotype correlations, criteria for selecting candidates for genetic testing, and implications for recombinant human growth hormone therapy. Additionally, we advocate for a shift in clinical mindset: from a descriptive to a biologically grounded framework. ISS should be regarded as a transitional label pending further endocrine and genetic clarification. Recognizing this paradigm shift will improve diagnostic accuracy, personalize treatment strategies, and ultimately enhance care for children with growth failure in the genomic era. Full article

It is well established that different fasting strategies offer a range of benefits and may even serve as potential therapeutic approaches for metabolic diseases. The biological effects of intermittent fasting (IF) are multidimensional, involving the induction of metabolic switching from glucose to fatty acid and ketone utilization, thereby enhancing fat metabolism and improving glucose tolerance and insulin sensitivity. In addition, IF modulates the growth hormone/insulin-like growth factor 1 (GH/IGF-1) axis by lowering IGF-1 levels, a change associated with enhanced cellular protection, reduced tumorigenesis, and delayed aging. Moreover, IF modulates key signaling pathways, including mitogen-activated protein kinases, Notch, and nuclear factor kappa B, which collectively contribute to reduced oxidative stress, attenuated inflammation, and hepatoprotection. Although fasting may present certain challenges, it is essential to be adequately informed about its potential benefits and appropriate preparatory strategies before undertaking various fasting protocols. This review summarizes the current knowledge on various IF protocols and periodic short-term fasting (PSTF) lasting more than 24 h and up to 72 h, highlighting the signaling pathways through which these interventions affect metabolic processes. Additionally, it aims to provide a practical guide for the safe preparation for PSTF lasting more than 24 h and up to 72 h. Full article

Insulin, a key hormone primarily involved in glucose metabolism, has emerged as a crucial modulator of bone metabolism. Increasing evidence suggests that insulin influences bone health, but its precise mechanism of action remains unestablished. This review explores the intricate relationship between insulin and bone health, as well as elucidating the mechanism of action involved. Animal models of type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) demonstrated distinct skeletal alterations, largely attributed to differences in insulin availability and associated metabolic dysfunction. Insulin deficiency in T1DM was associated with the deterioration of trabecular and cortical bone, whereas insulin resistance in T2DM primarily compromised trabecular bone quality. The route, frequency, and duration of insulin administration have been shown to influence bone-related outcomes. Studies involving insulin receptor silencing have suggested that insulin signalling is essential for normal bone development and maintenance. In humans, inconsistent findings on the effects of circulating insulin levels and insulin resistance on bone health were mainly attributed to heterogeneity in age, gender, metabolic status, study designs, population characteristics, and assessment methods. This review also highlights current knowledge gaps and underscores the need for longitudinal studies and mechanistic research. A clearer understanding of the insulin–bone axis may guide the development of targeted strategies to mitigate skeletal complications in individuals with diabetes mellitus. Full article

Biological, physiological, and psychological stressors cause a “stress response” in our bodies. Stressors that are sensorily perceived (either acute or chronic) trigger hormonal responses from the sympathetic nervous system—the SAM and HPA axis—that effect intended organs to alert the individual. Other stressors have a direct effect on the target organ(s) of the body—e.g., physical injury and wounds, toxins, ionizing, and UV radiation. Both kinds of stressors change cell equilibrium, often leading to reactive oxygen species (ROS) accumulation and cellular damage. Among the signaling pathways involved in fighting these stressors, the c-Jun-N-terminal kinases (JNK) respond to diverse kinds of stressors. This review focuses on JNK1 and JNK2, both of which are ubiquitously present in all cell types, and attention is paid to gastrointestinal tract epithelial cells and their response—including tight junction disruption and cytoskeletal changes. We discuss the seemingly opposite roles of JNK1 and JNK2 in helping cells choose pro-survival and pro-apoptotic pathways. We examine the common features of the JNK protein structure and the possibilities of discovering JNK-isoform-specific inhibitors since, although JNK1 and JNK2 are involved in multiple diseases, including cancer, obesity, diabetes, musculoskeletal and liver disease, no cell-specific or isoform-specific inhibitors are available. Full article

This overview explores the complex relationship between environmental factors, particularly obesity, and the timing of puberty, with a focus on how hormonal and genetic interactions are influenced by external conditions. Puberty (gonadarche) is characterised by the activation of the hypothalamic–pituitary–gonadal (HPG) axis. The onset and progression of puberty vary significantly among individuals, primarily due to genetic factors, with key genes like kisspeptin 1 (KISS1) and makorin ring finger protein 3 (MKRN3) playing a crucial role. Cohesively, this paper emphasises that environmental factors, particularly obesity and exposure to endocrine-disrupting chemicals (EDCs), have become significant influences on the timing of puberty. Childhood obesity has risen significantly in recent decades and the age of pubertal onset has declined over the same period. Obesity greatly disrupts hormone regulation in pre-pubertal children. Leptin accelerates the onset of puberty in girls but not in boys. The underlying mechanism is proposed to be the increase in Kiss1/GnRH signalling. On the contrary, excess leptin in boys suppresses testosterone production by increasing oestrogen conversion. Low adiponectin in obese girls may contribute to earlier puberty due to a reduced inhibition of Kiss1/GnRH signalling. Low adiponectin in boys is linked to delayed puberty due to its role in maintaining insulin sensitivity and testosterone production. Hyperinsulinemia influences pubertal timing through central and peripheral mechanisms. Insulin acting synergistically with leptin promotes the earlier onset of puberty in girls but not in boys. The effects of exposure to certain EDCs—mostly obesogenic chemicals that mimic the action of natural hormones—on the timing of puberty remain unclear; hence, further research on this topic is needed. Addressing and preventing obesity in children could potentially mitigate these alterations in pubertal timing. Full article

Phototropins (PHOTs), as blue light receptors, play a pivotal role in plant light signal perception and adaptive regulation, yet their functional characteristics in trees remain poorly understood. In this study, the PHOT gene family was identified in Populus trichocarpa, and it included three members, PtrPHOT1, PtrPHOT2.1, and PtrPHOT2.2, all of which were highly expressed in mature leaves. Using CRISPR/Cas9 gene editing technology, triple-gene mutations in the PtrPHOT1/2.1/2.2 (PtrPHOTs) were generated, providing initial insights into the functions of PHOTs in trees. Compared to the wild type (WT), triple-gene ptrphots mutants displayed curved and wrinkled leaves, reduced leaf area, and delayed phototropic responses, indicating the central role of PHOTs in blue light signal perception. The stomatal aperture recovery rate in mutants was only 40% of that observed in WT, accompanied by significant downregulation of the BLUS1 gene transcription levels, confirming the conservation of the PHOT-BLUS1-H⁺-ATPase signaling axis in stomatal regulation. Transcriptome of triple-gene ptrphots mutants revealed 1413 differentially expressed genes, of which were enriched in auxin response (upregulation of SAUR family genes), jasmonic acid (downregulation of JAZ genes), and light signaling pathways, suggesting that PHOTs could regulate plant adaptability by integrating light signals and hormone homeostasis. Overall, this study achieved the knockouts of three PtrPHOTs family genes, and characteristics of triple-gene ptrphots mutants elucidated the multifunctional roles of PHOTs in leaf development, phototropism, and stomatal movement in poplar. Our work provides a foundation for deciphering light signaling networks and molecular breeding in woody plants. Full article

Fertility is a dynamic, multifactorial process governed by hormonal, immune, metabolic, and environmental factors. Recent evidence highlights the gut microbiota as a key systemic regulator of reproductive health, with notable impacts on endometrial function, implantation, pregnancy maintenance, and the timing of birth. This review examines the gut–endometrial axis, focusing on how gut microbial communities influence reproductive biology through molecular signaling pathways. We discuss the modulatory roles of microbial-derived metabolites—including short-chain fatty acids, bile acids, and tryptophan catabolites—in shaping immune tolerance, estrogen metabolism, and epithelial integrity at the uterine interface. Emphasis is placed on shared mechanisms such as β-glucuronidase-mediated estrogen recycling, Toll-like receptor (TLR)-driven inflammation, Th17/Treg cell imbalance, and microbial translocation, which collectively implicate dysbiosis in the etiology of gynecological disorders including endometriosis, polycystic ovary syndrome (PCOS), recurrent implantation failure (RIF), preeclampsia (PE), and preterm birth (PTB). Although most current evidence remains correlational, emerging insights from metagenomic and metabolomic profiling, along with microbiota-depletion models and Mendelian randomization studies, underscore the biological significance of gut-reproductive crosstalk. By integrating concepts from microbiology, immunology, and reproductive molecular biology, this review offers a systems-level perspective on host–microbiota interactions in female fertility. Full article

Background/Objectives: Growth in childhood and adolescence is influenced by a complex interaction of genetic, environmental, and hormonal factors, with growth hormone (GH) and insulin-like growth factor 1 (IGF-1) playing crucial roles in linear growth and development. However, chronic inflammation, often detected in situations like inflammatory bowel disease and juvenile idiopathic arthritis, can significantly disrupt the GH/IGF-1 axis, causing a relevant growth impairment. Methods: We conducted a retrospective review focusing on the role of cytokines in the GH-IGF-1 axis and growth. Results: Inflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 have been shown to contribute to GH resistance through an array of mechanisms that involve the downregulation of GH receptors and alterations in IGF-1 metabolism. This disruption negatively impacts the growth plate, particularly by impairing chondrocyte proliferation and differentiation, which are essential for proper bone elongation. This review delves into the intricate relationship among growth, chronic inflammation, and GH-IGF-1 axis, emphasizing the contribution of inflammatory cytokines in modulating GH signaling. It also highlights how cytokines can interfere with the molecular pathways that regulate skeletal growth, ultimately leading to growth disturbances in children suffering from chronic inflammatory diseases. Conclusions: The findings underscore the importance of controlling inflammation in affected individuals to mitigate its detrimental effects on growth and ensure that children may reach their growth full potential. Full article

This study systematically elucidates the regulatory mechanisms and potential therapeutic value of the exercise-induced hormone Irisin in the pathological progression of cardiac fibrosis. Through comprehensive analysis and multidimensional data integration, we constructed a complete regulatory network of Irisin within the cardiovascular system, spanning its secretion, signal transduction, and precise regulatory control. Our findings demonstrate that exercise intervention significantly elevates circulating Irisin levels via the skeletal muscle–peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α)–fibronectin type III domain-containing protein 5 (FNDC5) signaling axis. Irisin establishes a multidimensional molecular barrier against cardiac fibrosis by targeting Sirtuin 1 (Sirt1) activation, inhibiting the transforming growth factor-beta (TGF-β)/Smad3 signaling pathway, and modulating the transcriptional activity of the mitochondrial biogenesis core factors PGC-1α and nuclear respiratory factor 1 (NRF-1). Moreover, the dual regulatory mechanism of the exercise–skeletal muscle–heart axis not only effectively suppresses the aberrant activation of cardiac fibroblasts but also significantly reduces collagen deposition, oxidative stress, and inflammatory infiltration by restoring mitochondrial dynamics balance. Taken together, this study reveals a novel exercise-mediated cardioprotective mechanism at the molecular interaction network level, thereby providing a theoretical basis for the development of non-pharmacological bio-intervention strategies targeting the Irisin signaling pathway and laying a translational foundation for precise exercise prescriptions in cardiovascular diseases. Full article