ObjectiveThis paper aims to observe the protective effect of Huamoyan granules on knee osteoarthritis （KOA） and explore whether its protective effect is oriented toward an anti-inflammatory direction by regulation of macrophage polarization， which can effectively inhibit the progression of pathological inflammatory response， reduce the release of inflammatory pain mediators， and downregulate the protein expression level of transient receptor potential vanilloid 1 （TRPV1）， so as to provide experimental evidence for its clinical application and investigate its action mechanism. MethodsAfter adaptive feeding， Sprague-Dawley （SD） rats were randomly divided into six groups： sham group， model group， celecoxib group， and high， medium， and low-dose synovitis granule groups （9.6， 4.8， 2.4 g·kg^-1）. The administration dose of celecoxib capsules was 20 mg·kg^-1. There were 10 rats in the sham group and 12 rats in the model group and each administration group. A KOA animal model was established by means of intra-articular injection of sodium iodoacetate into the knee joint. From the 10^th day of the experiment， each administration group was given intragastric administration at a dose of 10 mL·kg^-1 for 4 weeks. General conditions of rats in each group were assessed daily. The pressure pain threshold （PPT） to mechanical stimulation and joint diameter were recorded. X-ray examination was performed on the right knee joints of rats for imaging analysis. Enzyme linked immunosorbent assay （ELISA） was performed to detect the tumor necrosis factor-α （TNF-α）， serum interleukin-1β （IL-1β）， and other pro-inflammatory cytokines in rat serum samples， as well as the expression levels of neurogenic inflammatory mediators such as nerve growth factor （NGF） and calcitonin gene-related peptide （CGRP）. Histopathological changes in the knee joint synovial tissues were examined by hematoxylineosin （HE） staining. Safranin O-fast green staining was performed to observe and evaluate the degree of knee cartilage lesions. Western blot was employed to quantitatively analyze TRPV1， p38 mitogen-activated protein kinase （p38 MAPK）， and phosphorylated （p）-p38 MAPK in rat knee synovial tissues. Immunofluorescence （IF） was used to measure and assess M1/M2 macrophage polarization. ResultsCompared with those in the sham group， the circumference and joint diameter of the right knee were markedly enlarged in the model group （P<0.01）， while PPTs of rats showed a significant reduction （P<0.01）. The contents of IL-1β， TNF-α， CGRP， and NGF in rats' serum were significantly elevated （P<0.01）， and the synovial Krenn score was increased （P<0.01）. The Mankin score of cartilage tissue was increased （P<0.01）， and the protein expressions of TRPV1 and p-p38 MAPK/p38 MAPK were significantly upregulated （P<0.01）. The experimental intervention significantly reduced the proportion of pro-inflammatory M1 macrophages in the total macrophage population （P<0.01）， and the percentage of M2 macrophages was decreased （P<0.01）. The M1/M2 macrophage ratio was significantly elevated （P<0.01）. Knee joint diameters of all dose groups of Huamoyan granules and the celecoxib group were reduced （P<0.01） compared with those of the model group， and the PPT recovery speeds in the high and medium-dose groups of Huamoyan granules were more obvious （P<0.05）. The contents of IL-1β， CGRP， and NGF in the rats' serum in all administration groups were significantly reduced （P<0.05， P<0.01）， and the content of TNF-α in rats' serum was significantly reduced （P<0.01）. All dose groups of Huamoyan granules demonstrated significant reductions in both synovial Krenn score （P<0.05， P<0.01） and protein expression of TRPV1 and p-p38 MAPK/p38 MAPK in rats' synovial tissues （P<0.01）. The percentage of M1 macrophages in the synovial tissues of the celecoxib group and all dose groups of Huamoyan granules was decreased （P<0.01）. The percentage of M2 macrophages was increased （P<0.05）， and the M1/M2 ratio was decreased （P<0.01）. ConclusionHuamoyan granules can alleviate the inflammatory response of KOA， reduce the release of inflammatory pain mediators， and downregulate TRPV1 protein expression by regulating macrophage polarization. Its mechanism may be related to the TRPV1/p38 MAPK signaling pathway， thereby achieving the effect of improving peripheral pain hypersensitivity in KOA.

Objective: To analyze the epidemiological characteristics and influencing factors of severe fever with thrombocytopenia syndrome (SFTS) in Zhejiang Province from 2019 to 2023, so as to provide the reference for strengthening SFTS prevention and control. Methods: Data on laboratory-confirmed SFTS cases in Zhejiang Province from 2019 to 2023 were collected through the Infectious Disease Reporting Information System of Chinese Disease Prevention and Control Information System. Meteorological data, geographic environment and socioeconomic factors during the same period were collected from the fifth-generation European Centre for Medium-Range Weather Forecasts, Geospatial Data Cloud, and Zhejiang Statistical Yearbook, respectively. Descriptive epidemiological methods were used to analyze the epidemiological characteristics of SFTS from 2019 to 2023, and a Bayesian spatio-temporal model was constructed to analyze the influencing factors of SFTS incidence. Results: A total of 578 SFTS cases were reported in Zhejiang Province from 2019 to 2023, with an annual average incidence of 0.23/105. The peak period was from May to July, accounting for 52.60%. There were 309 males and 269 females, with a male-to-female ratio of 1.15∶1. The cases were mainly aged 50-<80 years, farmers, and in rural areas, accounting for 82.53%, 77.34%, and 75.43%, respectively. Taizhou City and Shaoxing City reported more SFTS cases, while Shaoxing City and Zhoushan City had higher annual average incidences of SFTS. The Bayesian spatio-temporal interaction model showed good goodness of fit. The results showed that mean temperature (RR=1.626, 95%CI: 1.111-2.378) and mean wind speed (RR=1.814, 95%CI: 1.321-2.492) were positively correlated with SFTS risk, while altitude (RR=0.432, 95%CI: 0.230-0.829) and population density (RR=0.443, 95%CI: 0.207-0.964) were negatively correlated with SFTS risk. Conclusions SFTS in Zhejiang Province peaks from May to July. Middle-aged and elderly people and farmers are high-risk populations. Taizhou City, Shaoxing City, and Zhoushan City are high-incidence areas. Mean temperature, mean wind speed, altitude, and population density can all affect the risk of SFTS incidence.

ObjectiveThis paper aims to observe the role of Danlou tablet in treating coronary heart disease （CHD） with phlegm-stasis intermingling syndrome in minipigs by improving platelet function and explore the potential pharmacological mechanism of Danlou tablet in regulating platelet function by using proteomics technology. MethodsThirty Bama minipigs were randomly divided into a normal control group （6 pigs） and a high-fat diet group （24 pigs）. After 2 weeks of high-fat diet feeding， the high-fat diet group was randomly subdivided into a model group， an atorvastatin group （1 mg·kg^-1）， and Danlou tablet groups （0.6 g·kg^-1 and 0.3 g·kg^-1）. All groups continued to receive a high-fat diet for 8 weeks after the procedure. The normal control group was given a regular diet， underwent only coronary angiography， and did not receive an interventional injury procedure. The model group and each administration group were fed a high-fat diet. Two weeks later， they underwent a coronary angiography injury procedure. After the procedure， drugs were mixed into the feed every morning for 8 consecutive weeks， with the minipigs maintained on a continuous high-fat diet during this period. Quantitative proteomics technology was further used to study platelet proteins， and differential proteins were obtained by screening. Bioinformatics analysis was performed to analyze key regulatory proteins and biological pathways involved in the therapeutic effect of Danlou tablet on CHD with phlegm-stasis intermingling syndrome. ResultsCompared with the normal control group， the model group showed a significant increase in total cholesterol （TC）， triglyceride （TG）， high-density lipoprotein cholesterol （HDL-C）， and low-density lipoprotein cholesterol （LDL-C） of minipigs' serum （P<0.01）， a significant shortening in prothrombin time of （PT） （P<0.01）， a coagulation function index， and an increase in whole blood viscosity （P<0.01） and platelet aggregation rate （P<0.01）. Moreover， the platelet morphology was altered， and the contents of endothelin-1 （ET-1） and nitric oxide （NO） were significantly increased （P<0.01）. Hemodynamic parameters were obviously abnormal， including significantly decreased systolic blood pressure （SBP）， diastolic blood pressure （DBP）， mean arterial pressure （MAP）， left ventricular systolic pressure （LVSP）， and left ventricular maximal positive dp/dt （LV+dp/dt_max） （P<0.01）. Left ventricular maximal negative dp/dt （LV-dp/dt_max） was significantly increased （P<0.01）. Besides， there were myocardial cell hypertrophy， obvious edematous degeneration， massive interstitial inflammatory cell infiltration， high degree of fibrosis， and coronary endothelial atherosclerosis. TC and TG levels in minipigs' serum were significantly reduced in Danlou tablet groups with 0.6 g·kg^-1 and 0.3 g·kg^-1 （P<0.05， P<0.01）， compared with those in the model group. LDL-C was decreased in the Danlou tablet group with 0.6 g·kg^-1 （P<0.05）. The whole blood viscosity under low and high shear conditions was significantly reduced in the Danlou tablet group with 0.6 g·kg^-1 （P<0.05）. In groups with all doses of Danlou tablet， maximum aggregation rate （MAR） and average aggregation rate （AAR） were significantly decreased （P<0.05， P<0.01）， and platelets' morphological changes such as pseudopodia extension were reduced. ET-1 levels in the serum were significantly reduced. In the Danlou tablet group with 0.6 g·kg^-1， NO level in the serum was reduced （P<0.05）. In groups with all doses of Danlou tablet， DBP and MAP were significantly increased （P<0.05）. In the Danlou tablet group with 0.6 g·kg^-1， LVSP and LV+dp/dt_max were significantly increased （P<0.05， P<0.01）， and LV-dp/dt_max was significantly decreased （P<0.05）. In groups with all doses of Danlou tablet， edematous degeneration in myocardial tissue was milder， and coronary artery lesion degree was significantly alleviated. Compared with the normal control group， there were 94 differentially expressed proteins in the model group， including 81 up-regulated and 13 down-regulated proteins. Compared with the model group， the Danlou tablet group with 0.6 g·kg^-1 showed 174 differentially expressed proteins， including 100 up-regulated and 74 down-regulated proteins. A total of 30 proteins were reversed after Danlou tablet intervention. Bioinformatics analysis revealed that its pharmacological mechanism may exert anti-platelet activation， aggregation， and adhesion effects through biological pathways such as regulation of actin cytoskeleton， platelet activation pathway， Fcγ receptor-mediated phagocytosis， as well as proteins such as growth factor receptor-bound protein 2 （GRB2）， Ras-related C3 botulinum toxin substrate 2 （RAC2）， RAC1， and heat shock protein 90 alpha family class A member 1 （HSP90AA1）. ConclusionDanlou tablet can effectively reduce platelet activation and aggregation， exerting a good therapeutic effect on CHD with phlegm-stasis intermingling syndrome in minipigs. Its pharmacological mechanism may involve regulating biological pathways such as actin cytoskeleton and platelet activation pathway， as well as proteins like GRB2， RAC2， RAC1， and HSP90AA1， thereby exerting a pharmacological effect in anti-platelet activation， aggregation， and adhesion.

Functional constipation （FC） is a common functional disorder of the intestines， mainly characterized by reduced bowel movement frequency， difficulty in defecation， a sensation of incomplete evacuation， and hard stools， which severely affect patients’ quality of life. Research indicates that the pathogenesis of FC is closely related to gut microbiota dysbiosis and abnormal bile acid secretion. Bile acids， as endogenous natural laxatives， promote bowel movements by enhancing colonic secretion and regulating intestinal motility； meanwhile， gut microbiota influence colonic transit function by regulating the enteric nervous system， immune system， and their metabolic products. Based on an overview of the relationship between gut microbiota and bile acid metabolism， this article systematically reviews the current research status on the mechanisms of traditional Chinese medicine （TCM） in treating FC by regulating the balance of the gut microbiota-bile acid axis. It is found that single Chinese medicinal herbs （such as Atractylodes macrocephala）， isolated compounds （such as Platycodon grandiflorum polysaccharides）， herbal formulas （such as Shanger huang pill）， acupuncture， and moxibustion can up-regulate the abundance of beneficial bacteria， reshape the microbial structure， correct bile acid metabolism， and activate the Takeda G-protein receptor 5/farnesoid X receptor pathway to treat FC.

Background Co-exposure to noise and microwave radiation occurs frequently. The central nervous system has been identified as a sensitive target organ for both noise and microwave exposure individually, and the underlying mechanisms remain poorly understood. The specific biological effects resulting from co-exposure to these two factors have yet to be fully elucidated. Objective To clarify the effects of co-exposure to noise and microwave on neurobehavior and hippocampal tissue structure, and to explore the underlying mechanism through the assessment of serum cytokines. Methods C57BL/6N mice were selected and randomly assigned to a blank control group, a noise group, a microwave group, and a combined noise & microwave exposure group. To establish the exposure models, the noise group was subjected to broadband noise at 100 dB for 2 h, while the microwave group received radiation at a central frequency of 9.375 GHz with an average power density of 12 mW·cm⁻² and a specific absorption rate of 2.58 W·kg⁻¹ for 15 min. Open field and tail suspension tests assessed anxiety-like emotional behaviour; novel object recognition and Y-maze tests evaluated cognitive function. Histological changes in hippocampal tissue were examined using haematoxylin and eosin (HE) staining, and Nissl staining under light microscopy. Serum cytokine levels were measured using radioimmunoassay and enzyme-linked immunosorbent assay (ELISA). Results After 3 d of exposure, the noise, microwave, and combined exposure groups showed significant reductions in exploration frequency, duration, and distance within the central zone of the open field test compared to the control group (P < 0.01); the combined exposure group exhibited increased ratios of peripheral-to-central exploration time and distance (P < 0.05). After 7 d of exposure, compared with the control group, the noise group maintained a decrease in central zone exploration time (P < 0.01), while the combined exposure group showed persistent decline across all central zone metrics (P < 0.05) and elevated peripheral-to-central ratios (P < 0.05); compared to the microwave group, the combined exposure group showed significant less time in the central zone (P < 0.05) and higher peripheral-to-central ratios (P < 0.05). Regarding behaviour and cognition, compared with the control group, the combined exposure group showed increased immobility time in the tail suspension test after 3 d of exposure (P < 0.01). At this interval, all exposure groups demonstrated reduced frequency and duration of novel object recognition (P < 0.05), with the combined exposure group showing a marked decrease in novel arm exploration time (P < 0.01). After 7 d of exposure, compared with the control group, the noise group showed reduced novel object recognition frequency (P < 0.05), and both the noise and microwave groups exhibited decreased novel arm exploration time (P < 0.05). Pathological alterations including an increased number of hyperchromatic nuclei and depleted Nissl bodies were observed in the CA3 and DG regions across all exposure groups with the most severe lesions observed in the combined exposure group. Serum levels of central nervous system-specific protein β (S-100β), glial fibrillary acidic protein (GFAP), and corticosterone (CORT) were significantly elevated in all exposure groups compared with the control group (P < 0.05). Aquaporin-4 (AQP4) levels increased in the combined exposure group (P < 0.05), while CXC chemokine ligand 10 (CXCL10) levels rose in both the noise and combined groups compared with the control group (P < 0.05). Specifically, S-100β and CXCL10 levels in the combined exposure group were higher than those in the microwave group (P < 0.05); moreover, levels of S-100β, GFAP, CORT, AQP4, and CXCL10 in the combined exposure group were significantly higher than those in the noise group (P < 0.05). Conclusion Combined exposure to noise and microwave radiation induces pathological changes in the hippocampus of mice, increases levels of serum stress hormones and neuro-specific biomarkers. These impairments are more severe than those observed following single-factor exposure. The underlaying mechanism may be related to systemic stress response, neuronal damage, astrocyte activation, and changes in blood-brain barrier permeability, leading to emotional behavioral abnormalities and cognitive decline.

Background Sunshine duration is closely associated with population mental health and emotional states, although its relationship with mental and behavioral disorders (MBD) remains insufficiently studied. Objective To analyze the effect of sunshine duration on hospital admissions for MBD in Zigong City, Sichuan Province. Methods Hospital admission records for MBD from 10 medical institutions, meteorological data, and ambient air pollutant concentrations were collected in Zigong City from January 1, 2019 to December 31, 2024. A distributed lag non-linear model (DLNM) was employed to calculate single-day and cumulative lag effects of different sunshine duration exposures—0 h (P₀, P₅, P₂₅), 6 h (P₇₅), and 10.4 h (P₉₅)—on hospitalization risks for MBD, stratified by diagnostic category, sex, and age groups. Results This study analyzed 36597 hospital admissions for MBD in Zigong City. The exposure-response curve for sunshine duration at lag 0 d exhibited an inverted N-shaped pattern, with minimum relative risk (RR) of hospitalizations observed at 14 h sunshine duration. The immediate effects of different levels of sunshine duration on the hospitalization risk for MBD, schizophrenia, schizotypal and delusional disorders (SSDD), and neurotic, stress-related and somatoform disorders (NSSD) were significant, with the cumulative effect peaking at lags 12–13 days. For extremely short sunshine duration 0 h, the maximum relative risk (RR) values (with 95% confidence intervals, 95%CI) of hospitalization risk were 1.209 (1.001, 1.459) at lag 1 d for SSDD patients and 1.398 (1.133, 1.724) at lag 0 d for NSSD patients, respectively. The cumulative effect on hospitalization risk induced by short sunshine duration 6 h was higher than that induced by extremely short sunshine duration 0 h and long sunshine duration 10.4 h. Among populations stratified by gender and age, male patients and those aged over 70 years had higher hospitalization risks. For short sunshine duration 6 h, the cumulative RR (CRR) value (95%CI) of hospitalization risk for male MBD patients was 3.373 (1.362, 8.358) at cumulative lag 0–12 d, which was higher than that for female patients [2.943 (1.471, 5.889) at cumulative lag 0–13 d]. The population aged over 70 years was more sensitive to single-day and cumulative lag effects on hospitalization risk than other age groups. For short sunshine duration 6 h, the RR and CRR values (95%CI) of single-day and cumulative lag effects on hospitalization risk were 1.336 (1.002, 1.783) at lag 0 day and 5.085 (1.680, 15.392) at cumulative lag 0–12 d, respectively. At lag 13 d, long sunshine duration 10.4 h exposure was associated with depression hospitalizations in patients <20 years with RR=1.127 (95%CI: 1.002, 1.270). Conclusion When the daily sunshine duration is less than 14 h, it will increase the hospitalization risk of MBD in the population to varying degrees, with both single-day and cumulative lag effects. It is recommended that the public, especially vulnerable groups such as people with MBD aged 70 years and above and those with depression under 20 years, strengthen health protection to reduce the health risks caused by changes in sunshine.

ObjectiveThe malaria parasites remodel the host erythrocyte structure by exporting parasite proteins that interact with the membrane skeleton proteins of red blood cells (RBCs), facilitating their intracellular survival and pathogenicity. Skeleton-binding protein 1 (SBP1) is a conserved exported protein across Plasmodium species. In Plasmodium falciparum, SBP1 has been reported to interact with erythrocyte membrane skeleton proteins 4.1R and spectrin, while its contribution to erythrocyte remodeling and parasite virulence in Plasmodium berghei (Pb) remains unclear. This study aims to determine whether PbSBP1 associates with the host cytoskeletal protein 4.1R and to investigate its role in the remodeling of host RBCs and the pathogenicity of Plasmodium berghei. MethodsIn Plasmodium berghei, the relationship between PbSBP1 and the erythrocyte cytoskeletal protein 4.1R was examined using co-immunoprecipitation. A Pbsbp1 gene knockout mutant of Plasmodium berghei (Pbsbp1∆) was generated based on the principle of double crossover homologous recombination. The deformability of erythrocytes infected with Pbsbp1∆ parasites was assessed using microfluidic methods. Microchannels with an array of cylindrical pillars were used to detect modifications in infected RBC deformability. The infected RBCs were squashed between the rows and recovered between the columns and the transit velocity (μm/s) of infected RBCs travelling through the microchannel was recorded. The component of the erythrocyte membrane skeleton junctional complex, tropomodulin (TMOD), was fluorescently labeled, and the cytoskeletal network of infected erythrocytes was imaged using super-resolution stochastic optical reconstruction microscopy (STORM) to analyze ultrastructural changes in the cytoskeleton of wild-type (WT) and Pbsbp1∆-infected erythrocytes. Actin-based junctional complexes were displayed as individual clusters by the labeled TMOD in the STORM images, and the cluster densities and distances between adjacent clusters of infected RBCs were calculated. Additionally, rodent malaria models (BALB/c mice) and experimental cerebral malaria models (C57BL/6 mice) were employed to monitor the growth of Pbsbp1∆ and WT parasites during the intraerythrocytic stage and their capacity to induce cerebral malaria in mice. ResultsPbSBP1 may participate in the remodeling of infected erythrocytes through direct or indirect interaction with the erythrocyte cytoskeletal protein 4.1R. Microfluidic assays revealed that the deformability of erythrocytes infected with Pbsbp1∆ parasites was significantly enhanced compared to those infected with WT parasites. STORM imaging further demonstrated that the ultrastructure of the erythrocyte cytoskeleton in Pbsbp1∆-infected cells was altered relative to that in WT-infected erythrocytes. The distances between nearest neighbors of clusters had a tendency to increase while the cluster densities were decreased in Pbsbp1∆-infected RBCs compared to WT-infected RBCs. Subsequent phenotypic analysis indicated that the growth rate of Pbsbp1∆ parasites during the intraerythrocytic stage was significantly slower than that of WT parasites, and their ability to induce cerebral malaria in mice was also attenuated. These findings suggest that PbSBP1 is involved in the remodeling of the erythrocyte membrane skeleton, likely through its direct or indirect interaction with protein 4.1R, thereby regulating the deformability of infected erythrocytes and influencing the pathogenicity of the blood-stage parasites. ConclusionThis study establishes a role for PbSBP1 in host erythrocyte remodeling and parasite virulence, providing new research strategies for the prevention and treatment of malaria.

low transit constipation （STC） is a common functional intestinal disorder caused by impaired colonic transit function， characterized by reduced bowel movement frequency， hard stools， and difficulty in defecation. The mitogen-activated protein kinase （MAPK） signaling pathway， which mainly includes extracellular signal-regulated kinase （ERK）， c-Jun N-terminal kinase （JNK）， and p38 subtypes， plays a critical regulatory role in the occurrence and development of STC. This paper systematically reviews the multiple pathogenic mechanisms of the MAPK signaling pathway in STC and the research progress of traditional Chinese medicine （TCM） intervention.At the mechanistic level， the MAPK signaling pathway promotes the progression of STC through the following links：（1） Activation of p38 upregulates the expression of aquaporin 3 （AQP3）/AQP4 in the colon， leading to excessive reabsorption of water in the intestinal lumen； （2） It forms a positive feedback loop with nuclear factor-κB （NF-κB） to maintain low-grade intestinal inflammation， releases inflammatory factors such as tumor necrosis factor-α （TNF-α） and interleukin-1β （IL-1β）， and inhibits smooth muscle contraction； （3） Overactivation of p38 downregulates the expression of occludin and mucin 2 while upregulates the expression of claudin-2， thereby disrupting the mucosal barrier； （4） The JNK/p38 signaling pathway activates the caspase cascade to induce apoptosis of intestinal epithelial cells， neurons， and interstitial cells of Cajal； （5） Abnormal ERK signaling and excessive activation of p38/JNK inhibit intestinal smooth muscle contraction and reduce 5-hydroxytryptamine secretion， ultimately resulting in impaired colonic transit function.At the intervention level， TCM compound formulas and single herbs have been proven to improve STC by regulating the MAPK signaling pathway. Their effects are syndrome type-dependent：yin-nourishing formulas （Zengye Chengqi Tang， Tongbian Tang） mainly regulate the ERK/AQP axis； yang-warming formulas （Jichuan Jian） target both ERK/JNK and anti-apoptosis； heat-clearing formulas （Sanren Tang） focus on p38/NF-κB anti-inflammation. A single drug can simultaneously cover multiple aspects including water metabolism， inflammation， barrier function， apoptosis， and intestinal motility.Current relevant studies still have limitations such as mechanisms mostly remaining at the correlational level and a lack of disease-syndrome integrated research models. Future studies should combine specific inhibitors or gene knockout to identify core targets， establish disease-syndrome integrated STC models， and use network pharmacology and molecular docking techniques to deeply analyze the fine mechanism of “component-target-phenotype”， so as to provide high-quality evidence for the precise regulation of the MAPK signaling pathway by TCM in the intervention of STC.

The functional realization of proteins and other biological macromolecules depends on conformational dynamics and allosteric regulation, and elucidating their molecular mechanisms is an important foundation for understanding life processes. Molecular dynamics simulations are a powerful tool for investigating conformational evolution at the atomic level. However, traditional methods are limited by simulation timescales and high free-energy barriers, making it difficult to effectively capture rare conformations and their transition pathways. As a result, the development of enhanced sampling techniques has become key to overcoming this bottleneck. As a classical enhanced sampling technique, metadynamics suffers from several shortcomings, including strong dependence on collective variables and significant errors caused by bias potential accumulation. This article reviews three major improvement strategies. The first combines stochastic resetting with metadynamics, using trajectory-resetting mechanisms to improve sampling efficiency while avoiding the difficulty of optimizing collective variables. The second, SinkMeta, employs a “sinking” bias effect to enable efficient exploration of specific regions and paths. The third, OPES-based hybrid methods, improve the stability of free-energy estimation by optimizing the target distribution or the way the bias is constructed. These methods provide new ideas for characterizing free-energy landscapes and studying conformational transitions in complex biological systems, while also promoting the continued development of enhanced sampling methodologies.

ObjectiveTo explore the mechanism of Shouhui Tongbian capsules in treating constipation based on the research foundation of its active components combined with network pharmacology and animal experiments. MethodsThe drug components were imported into SwissTargetPrediction to predict the targets of Shouhui Tongbian capsules， and constipation-related targets were collected from disease databases. A protein-protein interaction （PPI） network was constructed for the common targets shared by Shouhui Tongbian capsules and constipation to screen key targets， which was followed by gene ontology （GO） function and Kyoto encyclopedia of genes and genomes （KEGG） pathway enrichment analyses. A "bioactive component-target-pathway" network was constructed， and the core components of Shouhui Tongbian capsules in treating constipation were screened based on the topological parameters of this network. Molecular docking was employed to predict the binding affinity of core components to key targets. A mouse model of constipation was constructed to screen the key pathways and targets of the drug intervention in constipation. ResultsThe PPI network revealed six key constipation-related targets： protein kinase B （Akt1）， B-cell lymphoma-2 （Bcl-2）， glycogen synthase kinase-3β （GSK-3β）， cyclooxygenase-2 （PTGS2）， estrogen receptor 1 （ESR1）， and epidermal growth factor receptor （EGFR）. The KEGG pathway analysis showed that the phosphatidylinositol 3-kinase （PI3K）/Akt signaling pathway was the most enriched. The topological parameter analysis of the "bioactive component-target-pathway" network screened out the top 10 core components： auranetin， isosinensetin， naringin， diosmetin， quercetin， apigenin， luteolin， hesperidin， isorhapontigenin， and chrysophanol. Molecular docking results showed that the 10 core components had strong binding affinity with the 6 key targets. Animal experiments showed that after intervention with different doses of Shouhui Tongbian capsules， the time to the first black stool excretion was reduced and the fecal water content and small intestine charcoal propulsion rate of mice were improved. After treatment with Shouhui Tongbian capsules， the colonic mucosal injury and glandular arrangement were alleviated， and the muscle layer thickness was increased. Western blot results showed that Shouhui Tongbian capsules recovered the expression of apoptosis-related molecules mediated by the PI3K/Akt pathway in the colonic tissue of constipated mice. Terminal-deoxynucleotidyl transferase-mediated nick end labeling （TUNEL） results showed that the cell apoptosis rate of the colon significantly reduced after intervention with Shouhui Tongbian capsules. ConclusionThe results of network pharmacology and animal experiments confirmed that Shouhui Tongbian capsules can treat constipation through multiple targets and pathways. The capsules can effectively intervene in loperamide-induced constipation in mice by regulating the constipation indicators and reducing cell apoptosis in the colon tissue via activating the PI3K/Akt signaling pathway.