Skeletal muscle is the largest metabolic and endocrine organ in the body.As the basic unit of skeletal muscle,muscle fiber has high plasticity.Skeletal muscle fibers are mainly divided into oxidative and glycolytic muscle fibers,and muscle fibers type is an important factor affecting the contraction and energy metabolism of skeletal muscle.Understanding the molecular mechanism regulating skeletal muscle fiber type conversion is of great significance for regulating skeletal muscle-related diseases.Mitochondria is the energy factory of cell life activities,and the characteristics of mitochondria,namely the content,shape and distribution of mitochondria,are closely related to the function of mitochondria.The mitochon-drial characteristics of various types of muscle fiber are different,which is related to the difference of en-ergy metabolism of different muscle fiber types.Mitochondrial homeostasis is a dynamic equilibrium process,which is usually regulated by mitochondrial biogenesis,mitochondrial fusion and fission,mito-chondrial autophagy and other processes.These processes not only affect the morphology and quantity of mitochondria,but also affect the metabolic balance of glucose and fatty acids in the body.Many studies have also shown that mitochondria-mediated changes in the substrates of energy metabolism of skeletal muscle affect the type conversion process of skeletal muscle fiber.Exercise is a non-drug treatment that can generally promote the formation of oxidized muscle fibers by maintaining skeletal muscle mitochondri-al homeostasis.In this paper,the mitochondrial characteristics of different types of skeletal muscle fibers and the role of maintaining mitochondrial homeostasis in regulating muscle fiber type conversion were re-viewed.On this basis,the molecular mechanism of mitochondrial involvement in PGC1α,Ca2+and ROS signaling pathways mediated by fiber type conversion of skeletal muscle was summarized.Mitochondria are the energy factories of skeletal muscle,and targeted intervention through understanding their regulato-ry mechanism may be a new direction for the treatment of skeletal muscle-related diseases in the future.

In-fusion cloning technology,as a revolutionary and efficient molecular biology tool,has been applied in multiple research fields such as basic biology,biotechnology,and biomedicine.In this article,we introduce a teaching reform project suitable for undergraduate students in the course of"Molecular Bi-ology Laboratory",which utilizes in-Fusion cloning technology to construct a prokaryotic expression vector for alkaline phosphatase mutant genes.Through specific teaching cases,we systematically explored the design and implementation of experimental projects,and focused on analyzing the key and difficult points of the teaching content.Our teaching practice has found that the implementation of this educational re-form project has achieved very good results in enhancing students' core biological literacy,bioinformatics skills,research thinking,and innovation abilities.At the same time,the application of this technology can significantly improve the quality of experimental teaching,providing new ideas and practical refer-ences for promoting the reform and innovation of National First-Class Courses.

This study employed 16S r RNA gene high-throughput sequencing and metabolomics to explore the mechanism of Angelicae Dahuricae Radix polysaccharides(RP) in the treatment of ulcerative colitis(UC). A mouse model of UC was induced with 2. 5% dextran sulfate sodium. The therapeutic effects of RP on UC in mice were evaluated based on changes in body weight, disease activity index( DAI), and colon length, as well as pathological changes. RT-qPCR was performed to assess the m RNA levels of interleukin(IL)-6, IL-1β, tumor necrosis factor(TNF)-α, myeloperoxidase(MPO), mucin 2(Muc2), Occludin, Claudin2, and ZO-1 in the mouse colon tissue. ELISA was employed to measure the expression of IL-1β and TNF-α in the colon tissue. The intestinal permeability of mice was evaluated by the fluorescent dye permeability assay. Immunohistochemistry was employed to detect the expression of Muc2 and occludin in the colon tissue. Changes in gut microbiota and metabolites were analyzed by 16S r RNA sequencing and ultra-high-performance liquid chromatography coupled with quadrupole-orbitrap mass spectrometry( UPLC-Q-Exactive Plus Orbitrap MS), respectively. The results indicated that low-dose RP alleviated general symptoms, reduced colonic inflammation and intestinal permeability, and promoted Muc2 secretion and tight junction protein expression in UC mice. In addition, low-dose RP increased gut microbiota diversity in UC mice and decreased the relative abundance of harmful bacteria such as Ochrobactrum and Streptococcus. Twenty-seven differential metabolites were identified in feces, and low-dose RP restored the levels of disturbed metabolites. Notably, arginine and proline metabolism were the most significantly altered amino acid metabolic pathways following lowdose RP intervention. In conclusion, RP can ameliorate general symptoms, inhibit colonic inflammation, and maintain intestinal mucosal barrier integrity in UC mice by modulating gut microbiota composition and arginine and proline metabolism.
Animals ; Gastrointestinal Microbiome/drug effects* ; Colitis, Ulcerative/genetics* ; Mice ; Male ; Drugs, Chinese Herbal/administration & dosage* ; Polysaccharides/administration & dosage* ; Angelica/chemistry* ; Humans ; Colon/metabolism* ; Disease Models, Animal ; Mucin-2/metabolism* ; Tumor Necrosis Factor-alpha/metabolism*

OBJECTIVE: This study aimed to explore the association between body mass index (BMI) and mortality based on the 10-year population-based multicenter prospective study. METHODS: A general population-based multicenter prospective study was conducted at four sites in rural China between 2013 and 2023. Multivariate Cox proportional hazards models and restricted cubic spline analyses were used to assess the association between BMI and mortality. Stratified analyses were performed based on the individual characteristics of the participants. RESULTS: Overall, 19,107 participants with a sum of 163,095 person-years were included and 1,910 participants died. The underweight (< 18.5 kg/m ²) presented an increase in all-cause mortality (adjusted hazards ratio [ aHR] = 2.00, 95% confidence interval [ CI]: 1.66-2.41), while overweight (≥ 24.0 to < 28.0 kg/m ²) and obesity (≥ 28.0 kg/m ²) presented a decrease with an aHR of 0.61 (95% CI: 0.52-0.73) and 0.51 (95% CI: 0.37-0.70), respectively. Overweight ( aHR = 0.76, 95% CI: 0.67-0.86) and mild obesity ( aHR = 0.72, 95% CI: 0.59-0.87) had a positive impact on mortality in people older than 60 years. All-cause mortality decreased rapidly until reaching a BMI of 25.7 kg/m ² ( aHR = 0.95, 95% CI: 0.92-0.98) and increased slightly above that value, indicating a U-shaped association. The beneficial impact of being overweight on mortality was robust in most subgroups and sensitivity analyses. CONCLUSION This study provides additional evidence that overweight and mild obesity may be inversely related to the risk of death in individuals older than 60 years. Therefore, it is essential to consider age differences when formulating health and weight management strategies.
Humans ; Body Mass Index ; China/epidemiology* ; Male ; Female ; Middle Aged ; Prospective Studies ; Rural Population/statistics & numerical data* ; Aged ; Follow-Up Studies ; Adult ; Mortality ; Cause of Death ; Obesity/mortality* ; Overweight/mortality*

Skeletal muscle is the largest metabolic and endocrine organ in the body.As the basic unit of skeletal muscle,muscle fiber has high plasticity.Skeletal muscle fibers are mainly divided into oxidative and glycolytic muscle fibers,and muscle fibers type is an important factor affecting the contraction and energy metabolism of skeletal muscle.Understanding the molecular mechanism regulating skeletal muscle fiber type conversion is of great significance for regulating skeletal muscle-related diseases.Mitochondria is the energy factory of cell life activities,and the characteristics of mitochondria,namely the content,shape and distribution of mitochondria,are closely related to the function of mitochondria.The mitochon-drial characteristics of various types of muscle fiber are different,which is related to the difference of en-ergy metabolism of different muscle fiber types.Mitochondrial homeostasis is a dynamic equilibrium process,which is usually regulated by mitochondrial biogenesis,mitochondrial fusion and fission,mito-chondrial autophagy and other processes.These processes not only affect the morphology and quantity of mitochondria,but also affect the metabolic balance of glucose and fatty acids in the body.Many studies have also shown that mitochondria-mediated changes in the substrates of energy metabolism of skeletal muscle affect the type conversion process of skeletal muscle fiber.Exercise is a non-drug treatment that can generally promote the formation of oxidized muscle fibers by maintaining skeletal muscle mitochondri-al homeostasis.In this paper,the mitochondrial characteristics of different types of skeletal muscle fibers and the role of maintaining mitochondrial homeostasis in regulating muscle fiber type conversion were re-viewed.On this basis,the molecular mechanism of mitochondrial involvement in PGC1α,Ca2+and ROS signaling pathways mediated by fiber type conversion of skeletal muscle was summarized.Mitochondria are the energy factories of skeletal muscle,and targeted intervention through understanding their regulato-ry mechanism may be a new direction for the treatment of skeletal muscle-related diseases in the future.

In-fusion cloning technology,as a revolutionary and efficient molecular biology tool,has been applied in multiple research fields such as basic biology,biotechnology,and biomedicine.In this article,we introduce a teaching reform project suitable for undergraduate students in the course of"Molecular Bi-ology Laboratory",which utilizes in-Fusion cloning technology to construct a prokaryotic expression vector for alkaline phosphatase mutant genes.Through specific teaching cases,we systematically explored the design and implementation of experimental projects,and focused on analyzing the key and difficult points of the teaching content.Our teaching practice has found that the implementation of this educational re-form project has achieved very good results in enhancing students' core biological literacy,bioinformatics skills,research thinking,and innovation abilities.At the same time,the application of this technology can significantly improve the quality of experimental teaching,providing new ideas and practical refer-ences for promoting the reform and innovation of National First-Class Courses.

Aim To explore the effect and mechanism of the artesunate(ART)on hepatocellular carcinoma(HCC).Methods The cell lines MHCC-97H and HCC-LM3 were used to be detected.MTT and clone formation were used to determine the cell proliferation;Wound healing was used to detect the cell migration;Transwell was used to test the cell invasion.Flow-cy-tometry was used to detect cell apoptosis and cell cy-cle.RNA-seq and qRT-PCR was used to detect the genes expression.Results The proliferation,migra-tion and invasion of treated cells were obviously inhibi-ted(P＜0.01).Moreover,the apoptosis rate in-creased significantly,so did the proportion of G2/M cells.Transcriptomic analysis identified GADD45A as a potential target of ART through RNA-sequencing da-ta,and suggested that ART might induce apoptosis and cell cycle arrest through regulating the expression of GADD45A.In addition,the results of mechanism studies and signaling analysis suggested that GADD45A had interaction with its upstream gene NACC1(nucle-us accumbens associated 1).Moreover,after ART treatment,the expressions of GADD45A and NACC1 were changed significantly.Conclusion ART may be a potential drug to resist HCC by affecting the expres-sion of GADD45A and its upstream gene NACC1,which provides a new drug,a new direction and a new method for the clinical treatment of HCC.

Objective:To analyze the methylation characteristics of the lymphocyte-specific protein-tyrosine kinase (LCK) promoter region in the peripheral blood circulation of rheumatoid arthritis (RA) patients and its correlation with clinical indicators.Methods:Targeted methylation sequencing was used to compare the methylation levels of 7 CpG sites in the LCK promoter region in the peripheral blood of RA patients with healthy controls (HC) and osteoarthritis (OA) patients. Correlation analysis and ROC curve construction were performed with clinical information.Results:Non-parametric tests revealed that compared with HC [0.53(0.50, 0.57)] and OA patients [0.59(0.54, 0.62), H=47.17, P<0.001], RA patients [0.63(0.59, 0.68)] exhibited an overall increase in methylation levels. Simultaneously, when compared with the HC group [0.38(0.35, 0.41), 0.59(0.55, 0.63), 0.60(0.55, 0.64), 0.59(0.55, 0.63), 0.58(0.53, 0.62), 0.45(0.43, 0.49), 0.57(0.54, 0.61)], the RA group [0.46(0.42, 0.49), 0.70(0.65, 0.75), 0.70(0.66, 0.76), 0.70(0.65, 0.75), 0.69(0.64, 0.74), 0.55(0.51, 0.59), 0.68(0.63, 0.73)] showed a significant elevation in methylation levels at CpG sites cg05350315_60, cg05350315_80, cg05350315_95, cg05350315_101, cg05350315_104, cg05350315_128, and cg05350315_142, with statistically significant differences ( Z=-5.63, -5.89, -5.91, -5.89, -5.98, -5.95, -5.95, all P<0.001). Compared with the OA group [0.65(0.59, 0.69), 0.65(0.60, 0.69), 0.64(0.58, 0.68), 0.50(0.45, 0.54), 0.63(0.58, 0.67)], the RA group [0.70(0.66, 0.76), 0.70(0.65, 0.75), 0.69(0.64, 0.74), 0.55(0.51, 0.59), 0.68(0.63, 0.73)] exhibited a significant increase in methylation levels at CpG sites cg05350315_95, cg05350315_101, cg05350315_104, cg05350315_128, and cg05350315_142, with statistically significant differences ( Z=-3.56, -3.52, -3.60, -3.67, -3.62; P=0.036, 0.042, 0.031, 0.030, 0.030). Furthermore, Pearson correlation coefficient analysis revealed a positive correlation between the overall methylation level in this region and C-reactive protein (CRP) ( r=0.19, P=0.004) and erythrocyte sedimentation rate ( r=0.14, P=0.035). The overall methylation level of the LCK promoter region in the CRP (low) group [0.63 (0.58, 0.68)] was higher than that in the CRP (high) group [0.65(0.61, 0.70)], with statistically significant differences ( Z=2.60, P=0.009). Finally, by constru-cting a ROC curve, the discriminatory efficacy of peripheral blood LCK promoter region methylation levels for identifying RA patients, especially seronegative RA patients, from HC and OA groups was validated, with an AUC value of 0.78 (95% CI: 0.63, 0.93). Conclusion:This study provides insights into the methylation status and methylation haplotype patterns of the LCK promoter region in the peripheral blood of RA patients. The overall methylation level in this region is positively correlated with the level of inflammation and can be used to differentiate seronegative RA patients from the HC and OA patients.