BACKGROUND:Forskolin,a diterpenoid natural compound extracted from Coleus forskohlii,has a crucial regulatory role in skeletal muscle repair.However,the regulatory role of forskolin on myogenic differentiation of C2C12 skeletal muscle cells has not been fully explored.OBJECTIVE:To explore the effects of forskolin on the differentiation of C2C12 myoblast cell line and probe into the underlying molecular mechanisms.METHODS:C2C12 cells were treated with 0,0.1,0.25,0.5,1,5,10 and 20 μmol/L forskolin during growth,and cell proliferation was detected by cell counting kit-8 and qRT-PCR.C2C12 cells were treated with 0,0.25,0.5 and 1 μmol/L forskolin during the induction of myogenic differentiation.Immunofluorescence staining and qRT-PCR were used to detect C2C12 cells differentiation.Western blot was used to detect the expression level of myogenic differentiation-related signaling pathway proteins.RESULTS AND CONCLUSION:(1)The viability of C2C12 cells was decreased and cell proliferation was inhibited after treatment with high concentrations(＞1 μmol/L)of forskolin.(2)The qRT-PCR results showed that forskolin up-regulated the expression of Myh2,Myh4,Myomaker,but down-regulated the expression of Myh7 compared with the 0 μmol/L group,when C2C12 cells were differentiated for 4 days.Immunofluorescence staining results showed that the fusion index and myotube diameter of C2C12 cells were increased after forskolin treatment,and the number of myotubes was also increased.(3)Western blot results showed that the phosphorylated extracellular signal-regulated kinase 1/2 expression was inhibited;however,the phosphorylated protein kinase B was promoted after treatment with forskolin.The protein expression level of the myogenic differentiation transcription factor Myogenin was significantly up-regulated after treatment with forskolin.The above results demonstrate that forskolin may promote myogenic differentiation of C2C12 skeletal muscle cells through the extracellular signal-regulated kinase 1/2 and protein kinase B signaling pathway.

BACKGROUND:Forskolin,a diterpenoid natural compound extracted from Coleus forskohlii,has a crucial regulatory role in skeletal muscle repair.However,the regulatory role of forskolin on myogenic differentiation of C2C12 skeletal muscle cells has not been fully explored.OBJECTIVE:To explore the effects of forskolin on the differentiation of C2C12 myoblast cell line and probe into the underlying molecular mechanisms.METHODS:C2C12 cells were treated with 0,0.1,0.25,0.5,1,5,10 and 20 μmol/L forskolin during growth,and cell proliferation was detected by cell counting kit-8 and qRT-PCR.C2C12 cells were treated with 0,0.25,0.5 and 1 μmol/L forskolin during the induction of myogenic differentiation.Immunofluorescence staining and qRT-PCR were used to detect C2C12 cells differentiation.Western blot was used to detect the expression level of myogenic differentiation-related signaling pathway proteins.RESULTS AND CONCLUSION:(1)The viability of C2C12 cells was decreased and cell proliferation was inhibited after treatment with high concentrations(＞1 μmol/L)of forskolin.(2)The qRT-PCR results showed that forskolin up-regulated the expression of Myh2,Myh4,Myomaker,but down-regulated the expression of Myh7 compared with the 0 μmol/L group,when C2C12 cells were differentiated for 4 days.Immunofluorescence staining results showed that the fusion index and myotube diameter of C2C12 cells were increased after forskolin treatment,and the number of myotubes was also increased.(3)Western blot results showed that the phosphorylated extracellular signal-regulated kinase 1/2 expression was inhibited;however,the phosphorylated protein kinase B was promoted after treatment with forskolin.The protein expression level of the myogenic differentiation transcription factor Myogenin was significantly up-regulated after treatment with forskolin.The above results demonstrate that forskolin may promote myogenic differentiation of C2C12 skeletal muscle cells through the extracellular signal-regulated kinase 1/2 and protein kinase B signaling pathway.

ObjectiveTo elucidate the mechanism by which total flavonoids of Abelmoschi Corolla （TFA） treat immunoglobulin A （IgA） nephropathy （IgAN） through serum metabolomics analysis. MethodsSPF-grade male SD rats were randomly assigned into six groups （n=10）： blank， model， low-dose TFA （TFA-L， 27 mg·kg^-1）， medium-dose TFA （TFA-M， 54 mg·kg^-1）， high-dose TFA （TFA-H， 108 mg·kg^-1）， and losartan potassium （LST， 4.5 mg·kg^-1） groups. The remaining five groups， excluding the blank group， were modeled with bovine serum albumin （BSA）， lipopolysaccharide （LPS）， and carbon tetrachloride （CCl₄）. Specifically， from weeks 1 to 10， BSA was administered via gavage every other day， and a mixture of castor oil and CCl₄ was injected subcutaneously once a week， with LPS injected into the tail vein at weeks 6 and 8. After successful modeling， each intervention group was administrated with the medication prepared with distilled water once daily by gavage for a continuous period of 4 weeks. The levels of 24-hour urinary total protein （24 h UP） and serum creatinine （SCr） were quantified by kits， and the serum IgA level was determined by enzyme-linked immunosorbent assay （ELISA）. Renal pathological changes were observed by hematoxylin-eosin （HE） staining and periodic acid-Schiff （PAS） staining. Renal IgA deposition was assessed by immunofluorescence （IF）. Endoplasmic reticulum （ER） stress was observed by transmission electron microscopy. Western blot and immunohistochemistry （IHC） were employed to detect the expression of ER stress-related factors. Non-targeted metabolomics was used to screen differential metabolites for analysis， and key metabolites arachidonic acid （AA）， prostaglandin E₂ （PGE₂）， and cyclooxygenase-2 （COX-2） were validated. ResultsCompared with the blank group， the model group showed increased 24-hour urine protein （24 h UP） and serum creatinine （SCr） levels （P<0.01）， obvious renal pathological damage， elevated serum IgA level （P<0.01）， increased renal AA and PGE₂ levels （P<0.01）， and up-regulated protein levels of COX-2， glucose-regulated protein 78 （GRP78）， phosphorylated eukaryotic initiation factor 2α （P-EIF2α）， activating transcription factor 4 （ATF4）， inositol-requiring enzyme 1α （IRE1α）， and spliced X-box binding protein 1 （XBP1s） in the renal tissue （P<0.05， P<0.01）. Compared with the model group， the intervention groups showed reductions in 24 h UP and SCr levels （P<0.05， P<0.01）， alleviated renal pathological injury， decreased serum IgA level （P<0.05， P<0.01）， and reduced renal AA and PGE₂ levels （P<0.01）. Western blot and IHC results showed that TFA reduced the levels of COX-2， GRP78， P-EIF2α， ATF4， IRE1α， and XBP1s in the renal tissue （P<0.05， P<0.01）. Metabolomics results indicated that 51 commonly differential metabolites were found among the normal， model， and TFA-M groups. TFA ameliorated IgAN by affecting metabolic pathways related to the biosynthesis of arachidonic acid and arginine through L-aspartic acid， prostaglandin 2α， leukotriene B₄， leukotriene D₄， among others. ConclusionTFA can regulate the arachidonic acid metabolism pathway， thereby modulating ER stress， reducing renal damage， and ameliorating IgA nephropathy.

ObjectiveTo investigate the effect and mechanism of transplantation of human umbilical cord mesenchymal stem cell （hUC-MSC） with overexpression of the Numb gene in the treatment of cholestatic liver fibrosis （CLF）. MethodsThe technique of lentiviral transfection was used to induce the overexpression of the Numb gene in hUC-MSC （hUC-MSC^Numb-OE）， and hUC-MSC transfected with empty vector （hUC-MSC^OE-EV） was used as negative control. Bile duct ligation （BDL） was performed to establish a rat model of CLF， and then the rats were randomly divided into BDL group， hUC-MSC group， hUC-MSC^OE-EV group， and hUC-MSC^Numb-OE group， while a sham-operation group was also established. The rats in the intervention groups were given a single splenic injection of the corresponding cells after BDL， and samples were collected at the end of week 4. Related indicators were measured， including serum biochemistry， liver histopathology， the content of hydroxyproline （Hyp） in the liver， hepatic stellate cell activation， ductular reaction， liver regeneration， and the expression levels of key molecules in the Numb-p53 signaling axis. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for further comparison between two groups. ResultsCompared with the BDL group， the hUC-MSC group and the hUC-MSC^OE-EV group had significant reductions in the levels of serum biochemical parameters （aspartate aminotransferase， gamma-glutamyl transpeptidase， total bile acid， total bilirubin， and direct bilirubin）， liver fibrosis markers （the content of Hyp and the expression levels of alpha-smooth muscle actin， tumor necrosis factor-α， and transforming growth factor-beta 1）， and ductular reaction markers （the expression levels of CK7 and CK19） （all P <0.05）， and compared with the hUC-MSC^OE-EV group， the hUC-MSC^Numb-OE group had significantly greater improvements in the above indicators （all P <0.05）. In addition， compared with the hUC-MSC^OE-EV group， the hUC-MSC^Numb-OE group had significant improvements in the expression levels of liver regeneration-related markers （albumin and hepatocyte nuclear factor 4α） and the molecules associated with the Numb-p53 signaling axis （Numb， pNumb， Mdm2， and p53） （all P <0.05）. ConclusionOverexpression of the Numb gene can enhance the therapeutic effect of hUC-MSC on CLF， possibly by activating the Numb-PTB^L-p53-HNF4α axis， promoting the hepatic differentiation of hUC-MSCs and subsequently enhancing liver regeneration.

ObjectiveTo explore the efficacy and potential neural mechanisms of individualized precision rehabilitation combining multimodal neuromodulation technologies under the guidance of multidisciplinary team (MDT)-based whole process dynamic assessment in a patient with large-area cerebral infarction who responded poorly to conventional rehabilitation. MethodsA 38-year-old male patient presented with hemiplegia and complete aphasia following large-area cerebral infarction in the left fronto-temporo-parietal lobe and basal ganglia due to arterial dissection. Under the MDT framework, the patient underwent six months of inpatient rehabilitation and one month of outpatient follow-up. Multimodal assessments were performed at multiple time points using diffusion tensor imaging (DTI), functional magnetic resonance imaging (fMRI), three-dimensional gait analysis and 128-channel electroencephalogram (EEG) monitoring, combined with standardized scales, such as Chinese Rehabilitation Research Center Standard Aphasia Examination (CRRCAE), Loewenstein Occupational Therapy Cognitive Assessment (LOTCA), simplified Fugl-Meyer Assessment (FMA) and modified Barthel Index (MBI). The rehabilitation protocol integrated conventional therapies with multimodal interventions, including multi-target transcranial magnetic stimulation, brain-computer interface (BCI)-driven robotic hand training and task-oriented virtual reality upper limb training. ResultsAfter intervention, the patient showed significant improvements: LOTCA score increased by 16 points, CRRCAE subscale scores improved by 60% to 90%, total FMA score increased from 20 to 54, FMA-Balance reached 12, and MBI improved from 40 to 91. DTI revealed an increase in global fiber tract count, elevated fractional anisotropy in the corpus callosum and right corticospinal tract, and significantly increased amplitude of low-frequency fluctuations and regional homogeneity in specific brain regions on fMRI. Event-related desynchronization dynamically decreased during BCI training, and three-dimensional gait parameters showed overall improvement. ConclusionFor patients with large-area stroke who respond inadequately to conventional rehabilitation, an individualized precision rehabilitation system based on MDT whole-process dynamic assessment and integrating multimodal neuromodulation with conventional therapy can effectively enhance cognitive, language, motor functions and activities of daily living. Neuroimaging and electrophysiological findings suggest that the mechanism may involve promoting neural fiber remodeling and modulating regional brain activity.

For middle-aged and elderly patients with conditions such as spinal fractures and degenerative spinal diseases, spinal internal fixation is a core surgical procedure for reconstructing spinal stability, heavily relying on the biomechanical stability provided by pedicle screw systems. Whereas, these patients are often complicated by osteoporosis that can significantly compromise the stability of the bone-pedicle screw interface, leading to a marked increase in pedicle screw loosening and surgical failure rates. The bone cement-augmented pedicle screw technique, which involves injecting bone cement into the vertebral body or screw trajectory to optimize the mechanical properties of the bone-pedicle screw composite, has been proven to significantly enhance fixation strength and effectively prevent screw-related failures, thereby reducing the incidence of internal fixation failure in high-risk populations undergoing spinal fusion. However, the widespread clinical application of this technique has faced challenges such as inaccurate clinical decision-making (indication and contraindication selection), non-standardized operative practices, and insufficient awareness of complication prevention, resulting in considerable variability in clinical outcomes and even severe complications. To address this, Prof. Luo Fei from First Affiliated Hospital of Army Medical University initiated the project and the Chinese Association Orthopaedic Surgeons organized relevant experts to develop the Evidence-based clinical practice guideline for bone cement-augmented pedicle screw technique ( version 2025), based on current evidence. The guidelines put forward 8 recommendations regarding the clinical value, scope of application, and operational standards of the technique, aiming to provide evidence-based medical support and technical standardization for clinical decision-making.

Objective:To understand the trends of the disease burden of Alzheimer's disease(AD)attributable to high body mass index(BMI)and high fasting plasma glucose(FPG)in the past 30 years and future trends in China, and to provide suggestions for the prevention and treatment of AD.Methods:Based on the Global Burden of Disease Research Database(GBD), data on AD deaths and disability adjusted life years(DALYs)attributable to high BMI and high FPG were collected from 1990 to 2021 in Chinese and global populations.The Joinpoint log-linear regression model was used to explore and compare the changing trends of AD burden in China and globally from 1990 to 2021, and a Bayesian age-period-cohort model was constructed for predictive analysis.Results:In 2021, the age-standardized mortality and DALYs rates of AD attributed to high BMI in the Chinese population were 1.256/100, 000 and 24.751/100, 000, respectively, and those attributed to high FPG were 3.636/100, 000 and 66.721/100, 000, respectively.The age-standardized rates of mortality and DALYs of females were both higher than those of males.From 1990 to 2021, the age-standardized rates of mortality and DALYs of AD attributed to high BMI increased slowly at first and then rapidly in China, the corresponding average annual percent change(AAPC)and 95% confidence interval(95% CI)were 9.87%(9.63%-10.12%), and 9.81%(9.54%-10.09%), respectively( P<0.001). The age-standardized rates of mortality and DALYs of AD caused by high FPG showed a fluctuating upward trend, with AAPC of 0.29%(95% CI: 0.17%-0.41%)and 0.53%(95% CI: 0.45%-0.61%), respectively( P<0.001). It is predicted that by 2030, the age-standardized rates of mortality and DALYs of AD attributed to high BMI and high FPG in the whole population of China will increase to 4.87/100 000 and 97.20/100 000, both lower than the global level(5.45/100 000 and 100.24/100 000). In addition to a slight decline in the age-standardized mortality rate in Chinese men, the age-standardized rates of mortality and DALYs attributed to high BMI and high FPG in Chinese women and the global population will both show an upward trend. Conclusions:The burden of AD attributed to high BMI and high FPG is relatively severe, with gender differences, and is expected to increase slightly by 2030.It is recommended that early identification of key high-risk populations of AD should be strengthened, especially for the elderly and female groups.Interventions targeting modifiable risk factors should be carried out, and effective measures should be adopted to reduce the burden of AD.

Objective:To quantitatively evaluate the effects of left bundle branch block（LBBB）on left ventricular structure，function and myocardial perfusion using left ventricular pressure-strain loop and single photon emission computed tomography（SPECT），and to investigate the relationship between myocardial work，myocardial perfusion and pathological changes of left ventricular remodeling in left bundle branch block induced cardiomyopathy（LBBB-CM）.Methods:Fourteen male beagle dogs were selected，and the main trunk of the left bundle branch was ablated to create an LBBB dog model. Electrocardiogram（ECG），transesophageal echocardiography and arterial blood pressure data of LBBB dogs were collected before and 12 months after the ablation of left bundle branch trunk. Global and segmental myocardial work parameters were obtained by left ventricular pressure-strain loop. The differences of above parameters between baseline and 12 months after the ablation of left bundle branch were compared. SPECT was performed in LBBB dogs 12 months after the creation of LBBB. The hearts were harvested for anatomy observation and histopathological analysis in LBBB dogs and another 7 male beagle dogs（normal control group）matched by age and weight. The correlation between myocardial perfusion（percentage of regional tracer uptake）and myocardial work parameters，myocardial fibrosis in LBBB dogs were analyzed.Results:Compared with baseline，the left ventricular end-diastolic volume of 12 months after the ablation increased［（20.78 ± 5.32）ml vs（26.71 ± 7.94）ml， P = 0.003］，left ventricular ejection fraction decreased［（59.17 ± 5.67）% vs（47.69 ± 5.45）%， P<0.001］；left ventricular global/segmental longitudinal strain，global/segmental constructive work and global/segmental work efficiency decreased（all P<0.05），left ventricular global/segmental wasted work increased（all P<0.001）. Heterogenous perfusion defect was observed in LBBB dogs by SPECT，compared with lateral wall segments，the percentage of regional tracer uptake of septum was decreased（all P<0.05）. Gross anatomical and myocardial pathological changes were manifested as cardiomegaly，flaky or focal grayish thickening of endocardium，cardiomyocyte degeneration and fibrosis. Compared with normal control group，the collagen fiber volume fraction（CVF）in all segmental endocardium and partial segmental myocardium of LBBB dogs were significantly increased（all P<0.05）. Percentage of regional tracer uptake was positively correlated with segmental myocardial work（SMW）and segmental myocardial efficiency（SWE）（ r s = 0.49，0.31；both P<0.001），and negatively correlated with CVF and segmental wasted work（SWW）（ r s = -0.51，-0.49；both P<0.001）. Conclusions:Isolated LBBB is not benign，which can result in left ventricular remodeling，decreased cardiac constructive function，abnormal myocardial perfusion，endocardial fibrosis and myocardial fibrosis.The parameters of myocardial work assecsed by echocardiograpgy and myocardial perfusion，as non-invasive examination，can to some extent reflect the degree of left ventricular remodeling in LBBB-CM.

Adenosine triphosphate(ATP),as a rich energy currency in cells,is released into the extracellular space through a variety of regulatory mechanisms.The role of extracellular ATP(eATP)and related purine and pyrimidine nucleotides as extracellu-lar signal molecules regulating immune cell function has been reported as evidence of purine signal transduction and has become the focus of attention as a therapeutic target for various diseases.Mast cells(MC)are distributed in tissues that come into contact with the external environment and are the first immune cells to respond to non-microbial environmental antigens.Although eATP is considered to be an activator of MC,the details remain to be further elucidated.This article describes the role of purine receptor signaling in MC degranulation.It expands the further understanding of the mechanism of allergic diseases,and further provides ideas for finding new targets for the treatment of allergic diseases and formulating new treatment strategies.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.