生理学报最新文献

Metabolic diseases characterized by an imbalance in energy homeostasis represent a significant global health challenge. Individuals with metabolic diseases often suffer from complications related to disorders in lipid metabolism, such as obesity and non-alcoholic fatty liver disease (NAFLD). Understanding core genes involved in lipid metabolism can advance strategies for the prevention and treatment of these conditions. Stearoyl-CoA desaturase 1 (SCD1) is a key enzyme in lipid metabolism that converts saturated fatty acids into monounsaturated fatty acids. SCD1 plays a crucial regulatory role in numerous physiological and pathological processes, including energy homeostasis, glycolipid metabolism, autophagy, and inflammation. Abnormal transcription and epigenetic activation of Scd1 contribute to abnormal lipid accumulation by regulating multiple signaling axes, thereby promoting the development of obesity, NAFLD, diabetes, and cancer. This review comprehensively summarizes the key role of SCD1 as a metabolic hub gene in various (patho)physiological contexts. Further it explores potential translational avenues, focusing on the development of novel SCD1 inhibitors across interdisciplinary fields, aiming to provide new insights and approaches for targeting SCD1 in the prevention and treatment of metabolic diseases.

Mitochondrial metabolism is crucial for providing energy and heme precursors during erythroid development. Oxoglutarate dehydrogenase complex (OGDC) is a key enzyme in the mitochondrial tricarboxylic acid (TCA) cycle, and its level gradually increases during erythroid development, indicating its significant role in erythroid development. The aim of the present study was to explore the role and mechanism of OGDC in erythroid development. In this study, we treated erythroid progenitor cells with CPI-613, a novel lipoic acid analog that competitively inhibits OGDC. The results showed that CPI-613 inhibited erythropoietin (EPO)-induced differentiation and enucleation of human CD34⁺ hematopoietic stem cells into erythroid cells, suppressed cell proliferation, and induced apoptosis. The results of in vivo experiments showed that CPI-613 also hindered the recovery of mice from acute hemolytic anemia. Further mechanism research results showed that CPI-613 increased reactive oxygen species (ROS) in erythroid progenitor cells, inhibited mitochondrial respiration, caused mitochondrial damage, and suppressed heme synthesis, thereby inhibiting erythroid differentiation. Clinical research results showed that oxoglutarate dehydrogenase (OGDH) protein expression levels were up-regulated in bone marrow cells of polycythemia vera (PV) patients. Treatment with CPI-613 significantly inhibited the excessive proliferation and differentiation of erythroid progenitor cells of the PV patients. These findings demonstrates the critical role of OGDC in normal erythroid development, suggesting that inhibiting its activity could be a novel therapeutic strategy for treating PV.

Obesity is a worldwide health problem. An imbalance in energy metabolism is an important cause of obesity and related metabolic diseases. Our previous studies showed that inhibition of miR-429 increased the protein level of uncoupling protein 1 (UCP1) in beige adipocytes; however, whether local inhibition of miR-429 in subcutaneous adipose tissue affects diet-induced obesity and related metabolic disorders remains unclear. The aim of this study was to investigate the effect of local overexpression of miR-429 sponge in subcutaneous adipose tissue on obesity and related metabolic disorders. The control adeno-associated virus (AAV) or AAV expressing the miR-429 sponge was injected into mouse inguinal white adipose tissue. Seven days later, the mice were fed a high-fat diet for 10 weeks to induce obesity. The effects of the miR-429 sponge on body weight, adipose tissue weight, plasma glucose and lipid levels, and hepatic lipid content were explored. The results showed that the overexpression of miR-429 sponge in subcutaneous white adipose tissue reduced body weight and fat mass, decreased fasting blood glucose and plasma cholesterol levels, improved glucose tolerance, and alleviated hepatic lipid deposition in mice. Mechanistic investigation showed that the inhibition of miR-429 significantly upregulated the expression of UCP1 in adipocytes and adipose tissue. These results suggest that local inhibition of miR-429 in subcutaneous white adipose tissue ameliorates obesity and related metabolic disorders potentially by upregulating UCP1, and miR-429 is a potential therapeutic target for the treatment of obesity and related metabolic disorders.

Steroid-induced osteonecrosis of femoral head (SONFH) is a disease characterized by femoral head collapse and local pain caused by excessive use of glucocorticoids. Peroxisome proliferator-activated receptor-γ (PPARγ) is mainly expressed in adipose tissue. Wnt/β-catenin, AMPK and other related signaling pathways play an important role in regulating adipocyte differentiation, fatty acid uptake and storage. Bone marrow mesenchymal cells (BMSCs) have the ability to differentiate into adipocytes or osteoblasts, and the use of hormones upregulates PPARγ expression, resulting in BMSCs biased towards adipogenic differentiation. The increase of adipocytes affects the blood supply and metabolism of the femoral head, and the decrease of osteoblasts leads to the loss of trabecular bone, which eventually leads to partial or total ischemic necrosis and collapse of the femoral head. MicroRNAs (miRNAs) are a class of short non-coding RNAs that regulate gene expression by inhibiting the transcription or translation of target genes, thereby affecting cell function and disease progression. Studies have shown that miRNAs affect the progression of SONFH by regulating PPARγ lipid metabolism-related signaling pathways. Therefore, it may be an accurate and feasible SONFH treatment strategy to regulate adipogenic-osteoblast differentiation in BMSCs by targeted intervention of miRNA differential expression to improve lipid metabolism. In this paper, the miRNA-mediated PPARγ-related signaling pathways were classified and summarized to clarify their effects on lipid metabolism in SONFH, providing a theoretical reference for miRNA targeted therapy of SONFH, and then providing scientific evidence for SONFH precision medicine.

This study aims to investigate the effects of renin inhibitor aliskiren on kidney injury in human angiotensinogen-renin (AGT-REN) double transgenic hypertensive (dTH) mice and explore its possible mechanism. The dTH mice were divided into hypertension group (HT group) and aliskiren intervention group (HT+Aliskiren group), while wild-type C57BL/6 mice were served as the control group (WT group). Blood pressure data of mice in HT+Aliskiren group were collected after 28 d of subcutaneous penetration of aliskiren (20 mg/kg), and the damage of renal tissue structure and collagen deposition were observed by HE, Masson and PAS staining. The ultrastructure of kidney was observed by transmission electron microscope. Coomassie bright blue staining and biochemical analyzer were used to detect renal function injury. The expression of renin-angiotensin system (RAS) was determined by ELISA and immunohistochemistry. The contents of superoxide dismutase (SOD) and malondialdehyde (MDA) in kidney were determined by chemiluminescence method. The content of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit p47^phox, inducible nitric oxide synthase (iNOS), 3-nitrotyrosine (3-NT), NADPH oxidase 2 (NOX2) and NADPH oxidase 4 (NOX4) were detected by Western blot analysis. The results showed that compared with WT group, the blood pressure of mice in HT group was significantly increased. The renal tissue structure in HT group showed glomerular sclerosis, severe interstitial tubular injury, and increased collagen deposition. In addition, 24 h urinary protein, serum creatinine and urea levels increased. Serum and renal tissue levels of angiotensin II (Ang II) were increased, serum angiotensin-(1-7) [Ang-(1-7)] expression was decreased, and renal Ang-(1-7) expression was elevated. The expressions of ACE, Ang II type 1 receptor (AT₁R) and MasR in renal tissue were increased, while the expression of ACE2 was decreased. MDA content increased, SOD content decreased, and the expressions of p47^phox, iNOS, 3-NT, NOX2 and NOX4 were increased. However, aliskiren reduced blood pressure in dTH mice, improved renal structure and renal function, reduced Ang II and Ang-(1-7) levels in serum and renal tissue, reduced the expression of ACE and AT₁R in renal tissue, increased the expression of ACE2 and MasR in renal tissue, and decreased the above levels of oxidative stress indexes in dTH mice. These results suggest that aliskiren may play a protective role in hypertensive renal injury by regulating the balance between ACE-Ang II-AT₁R and ACE2-Ang-(1-7)-MasR axes and inhibiting oxidative stress.

Persistent inflammation plays a pivotal role in the initiation and progression of renal fibrosis. Activation of the pattern recognition receptor retinoic acid-inducible gene-I (RIG-I) is implicated in the initiation of inflammation. This study aimed to investigate the upstream mechanisms that regulates the activation of RIG-I and its downstream signaling pathway. Eight-week-old male C57BL/6 mice were used to establish unilateral ureteral obstruction (UUO)-induced renal fibrosis model, and the renal tissue samples were collected 14 days later for analysis. Transforming growth factor-β (TGF-β)-treated mouse renal tubular epithelial cells were used in in vitro studies. The results demonstrated that, compared to the control group, UUO kidney exhibited significant fibrosis, which was accompanied by the increases of RIG-I, p-NF-κB p65 and inflammatory cytokines, such as TNF-α and IL-1β. Additionally, the protein level of the E3 ubiquitin ligase RNF125 was significantly downregulated and predominantly localized in the renal tubular epithelial cells. Similarly, the treatment of tubular cells with TGF-β induced the increases in RIG-I, p-NF-κB p65 and inflammatory cytokines while decreasing RNF125. Co-immunoprecipitation (Co-IP) assays confirmed that RNF125 was able to interact with RIG-I. Overexpression of RNF125 promoted the ubiquitination of RIG-I, and accelerated its degradation via the ubiquitin-proteasome pathway. Overexpression of RNF125 in UUO kidneys and in vitro tubular cells effectively mitigated the inflammatory response and renal fibrosis. In summary, our results demonstrated that the decrease in RNF125 under pathological conditions led to reduction in RIG-I ubiquitination and degradation, activation of the downstream NF-κB signaling pathway and increase in inflammatory cytokine production, which promoted the progression of renal fibrosis.

Esophageal squamous cell carcinoma (ESCC) is a prevalent malignancy of the digestive tract that poses a significant threat to human health, with an incidence rate that continues to rise globally. Increasing research highlights the crucial role of non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), in regulating ferroptosis and contributing to the malignant progression of ESCC. These ncRNAs influence the proliferation, apoptosis, and invasion capabilities of ESCC cells by modulating iron metabolism and redox balance. miRNAs can regulate cellular iron accumulation and oxidative stress by targeting ferroptosis-related genes; lncRNAs may indirectly affect iron metabolic pathways by competitively binding to miRNAs; circRNAs, through a sponge effect, may regulate the activity of miRNAs. This review systematically summarizes the mechanisms of ncRNAs-mediated regulation of ferroptosis in ESCC, focusing on molecular mechanisms, regulatory networks, and their specific roles in the ferroptosis process. Additionally, the potential of ncRNAs in ESCC diagnosis, prognosis assessment, and therapeutic intervention is discussed, aiming to provide new insights and targets for ferroptosis-based tumor therapy.

The present study aimed to investigate the effects of eccentric treadmill exercise on adaptive hypertrophy of skeletal muscle in rats. Thirty-two 3-month-old Sprague Dawley (SD) rats were selected and randomly assigned to one of the four groups based on their body weights: 2-week quiet control group (2C), 2-week downhill running exercise group (2E), 4-week quiet control group (4C), and 4-week downhill running exercise group (4E). The downhill running protocol for rats in the exercise groups involved slope of -16°, running speed of 16 m/min, training duration of 90 min, and 5 training sessions per week. Twenty-four hours after the final session of training, all the four groups of rats underwent an exhaustion treadmill exercise. After resting for 48 h, all the rats were euthanized and their gastrocnemius muscles were harvested for analysis. HE staining was used to measure the cross-sectional area (CSA) and diameter of muscle fibers. Transmission electron microscope was used to observe the ultrastructural changes in muscle fibers. Purithromycin surface labeling translation method was used to measure protein synthesis rate. Immunofluorescence double labeling was used to detect the colocalization levels of lysosomal-associated membrane protein 2 (Lamp2)-leucyl-tRNA synthetase (LARS) and Lamp2-mammalian target of rapamycin (mTOR). Western blot was used to measure the protein expression levels of myosin heavy chain (MHC) IIb and LARS, as well as the phosphorylation levels of mTOR, p70 ribosomal protein S6 kinase (p70S6K), and eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1). The results showed that, compared with the 2C group rats, the 2E group rats showed significant increases in wet weight of gastrocnemius muscle, wet weight/body weight ratio, running distance, running time, pre- and post-exercise blood lactate levels, myofibrillar protein content, colocalization levels of Lamp2-LARS and Lamp2-mTOR, and LARS protein expression. Besides these above changes, compared with the 4C group, the 4E group further exhibited significantly increased fiber CSA, fiber diameter, protein synthesis rate, and phosphorylation levels of mTOR, p70S6K, and 4E-BP1. Compared with the quiet control groups, the exercise groups exhibited ultrastructural damage of rat gastrocnemius muscle, which was more pronounced in the 4E group. These findings suggest that eccentric treadmill exercise may promote mTOR translocation to lysosomal membrane, activating mTOR signaling via up-regulating LARS expression. This, in turn, increases protein synthesis rate through the mTOR-p70S6K-4E-BP1 signaling pathway, promoting protein deposition and inducing adaptive skeletal muscle hypertrophy. Although the ultrastructural changes of skeletal muscle are more pronounced, the relatively long training cycles during short-term exercise periods have a more significant effect on promoting gastrocnemius muscle protein synthesis and adaptive hypertrophy.

Parkinson's disease (PD) is a common neurodegenerative disorder mainly related to mitochondrial dysfunction of dopaminergic neurons in the midbrain substantia nigra. This study aimed to investigate the effects of exercise preconditioning on motor deficits and mitochondrial function in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model. Eight-week-old male C57BL/6J mice were randomly divided into four groups: sedentary + saline (SS), sedentary + MPTP (SM), exercise + saline (ES), and exercise + MPTP (EM) groups. Mice in the ES and EM groups received 4 weeks of treadmill training, and then SM and EM groups were treated with MPTP for 5 days. Motor function was assessed by behavioral tests, and morphological and functional changes in dopaminergic neurons and mitochondria in the substantia nigra of the midbrain were evaluated using immunohistochemistry, Western blot, and transmission electron microscopy technology. The results showed that, compared with the SM group, the EM group exhibited significantly improved motor ability, up-regulated protein expression levels of tyrosine hydroxylase (TH) and dopamine transporter (DAT) in the midbrain, and down-regulated protein expression of α-synuclein (α-Syn) in the mitochondria of substantia nigra. Compared with the SM group, the EM group showed up-regulated protein expression levels of mitochondrial fusion proteins, including optical atrophy protein 1 (OPA1) and mitofusin 2 (MFN2), and biogenesis-related proteins, including peroxisome proliferator activated receptor gamma coactivator 1α (PGC-1α) and mitochondrial transcription factor A (TFAM), while the protein expression levels of dynamin-related protein 1 (DRP1) and mitochondrial fission protein 1 (FIS1) were significantly down-regulated. Compared with the SM group, the EM group showed significantly reduced damage to substantia nigra mitochondria, restored mitochondrial membrane potential and ATP production, and decreased levels of reactive oxygen species (ROS). These results suggest that 4-week treadmill pre-training can alleviate MPTP-induced motor impairments in PD mice by improving mitochondrial function, providing a theoretical basis for early exercise-based prevention of PD.

Tripartite motif-containing (TRIM) family proteins are crucial E3 ubiquitin ligases that have garnered significant attention for their regulatory roles in bone metabolism in recent years. This article reviews the function and regulatory mechanisms of TRIM family proteins in bone metabolism, focusing on their dual roles in bone formation and resorption. It also provides a detailed analysis of signaling pathways and molecular mechanisms by which TRIM family members regulate the activities of osteoblasts and osteoclasts. Research findings suggest that modulating the expression or activity of TRIM family proteins could be beneficial for treating bone diseases such as osteoporosis. This review highlights the molecular mechanisms of TRIM family members in bone physiology and pathology, aiming to provide theoretical basis and scientific guidance for developing novel therapeutic strategies for bone diseases.