Exercise fatigue is a complex physiological and psychological phenomenon that includes peripheral fatigue in the muscles and central fatigue in the brain. Peripheral fatigue refers to the loss of force caused at the distal end of the neuromuscular junction, whereas central fatigue involves decreased motor output from the primary motor cortex, which is associated with modulations at anatomical sites proximal to nerves that innervate skeletal muscle. The central regulatory failure reflects a progressive decline in the central nervous system’s capacity to recruit motor units during sustained physical activity. Emerging evidence highlights the critical involvement of central neurochemical regulation in fatigue development, particularly through neurotransmitter-mediated modulation. Alterations in neurotransmitter release and receptor activity could influence excitatory and inhibitory signal pathways, thus modulating the perception of fatigue and exercise performance. Increased serotonin (5-HT) could increase perception of effort and lethargy, reduce motor drive to continue exercising, and contribute to exercise fatigue. Decreased dopamine (DA) and noradrenaline (NE) neurotransmission can negatively impact arousal, mood, motivation, and reward mechanisms and impair exercise performance. Furthermore, the serotonergic and dopaminergic systems interact with each other; a low 5-HT/DA ratio enhances motor motivation and improves performance, and a high 5-HT/DA ratio heightens fatigue perception and leads to decreased performance. The expression and activity of neurotransmitter receptors would be changed during prolonged exercise to fatigue, affecting the transmission of nerve signals. Prolonged high-intensity exercise causes excess 5-HT to overflow from the synaptic cleft to the axonal initial segment and activates the 5-HT1A receptor, thereby inhibiting the action potential of motor neurons and affecting the recruitment of motor units. During exercise to fatigue, the DA secretion is decreased, which blocks the binding of DA to D1 receptor in the caudate putamen and inhibits the activation of the direct pathway of the basal ganglia to suppress movement, meanwhile the binding of DA to D2 receptor is restrained in the caudate putamen, which activates the indirect pathway of the basal ganglia to influence motivation. Furthermore, other neurotransmitters and their receptors, such as adenosine (ADO), glutamic acid (Glu), and γ‑aminobutyric acid (GABA) also play important roles in regulating neurotransmitter balance and fatigue. The occurrence of central fatigue is not the result of the action of a single neurotransmitter system, but a comprehensive manifestation of the interaction between multiple neurotransmitters. This review explores the important role of neurotransmitters and their receptors in central motor fatigue, reveals the dynamic changes of different neurotransmitters such as 5-HT, DA, NE, and ADO during exercise, and summarizes the mechanisms by which these neurotransmitters and their receptors regulate fatigue perception and exercise performance through complex interactions. Besides, this study presents pharmacological evidence that drugs such as agonists, antagonists, and reuptake inhibitors could affect exercise performance by regulating the metabolic changes of neurotransmitters. Recently, emerging interventions such as dietary bioactive components intake and transcranial electrical stimulation may provide new ideas and strategies for the prevention and alleviation of exercise fatigue by regulating neurotransmitter levels and receptor activity. Overall, this work offers new theoretical insights into the understanding of exercise central fatigue, and future research should further investigate the relationship between neurotransmitters and their receptors and exercise fatigue.

Objective To clarify the current development status and research hotspots in the field of experimental drug management in China through data mining by bibliometric. Methods Key words such as “experiment”, “drug”, and “management” were used to search the Chinese literature in China National Knowledge Infrastructure （CNKI）. The title, author name, author affiliation, Chinese abstract, Chinese keywords, publication period, journal name, and other content of the literature were extracted from the literature. Cluster analysis was performed by CNKI literature visualization analysis system, CiteSpace and other software, and a network knowledge map was drawn. Results The literature in the field of experimental drug management in China was first published in 1994, and a total of 140 articles were published until 2022. Among them, 20 articles were supported by relevant funds, and the keyword co-occurrence frequency was highest among “subjects”. The most frequently published medium was the Chinese Pharmacological Yearbook. Conclusion At present, the quantity and quality of literature in the field of experimental drug management in China were relatively small, and the cooperation and communication among authors were not close. The funding from various fund projects in this field was also lacking. These factors led to a lower overall development level and slower development speed in this field.

BACKGROUND:Osteosarcoma has a complex pathogenesis and a poor prognosis.While advancements in medical technology have led to some improvements in the 5-year survival rate,substantial progress in its treatment has not yet been achieved. OBJECTIVE:To screen key molecular markers in osteosarcoma,analyze their relationship with osteosarcoma treatment drugs,and explore the potential disease mechanisms of osteosarcoma at the molecular level. METHODS:GSE99671 and GSE284259(miRNA)datasets were obtained from the Gene Expression Omnibus database.Differential gene expression analysis and Weighted Gene Co-expression Network Analysis(WGCNA)on GSE99671 were performed.Functional enrichment analysis was conducted using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes separately for the differentially expressed genes and the module genes with the highest positive correlation to the disease.The intersection of these module genes and differentially expressed genes was taken as key genes.A Protein-Protein Interaction network was constructed,and correlation analysis on the key genes was performed using CytoScape software,and hub genes were identified.Hub genes were externally validated using the GSE28425 dataset and text validation was conducted.The drug sensitivity of hub genes was analyzed using the CellMiner database,with a threshold of absolute value of correlation coefficient|R|>0.3 and P<0.05. RESULTS AND CONCLUSION:(1)Differential gene expression analysis identified 529 differentially expressed genes,comprising 177 upregulated and 352 downregulated genes.WGCNA analysis yielded a total of 592 genes with the highest correlation to osteosarcoma.(2)Gene Ontology enrichment results indicated that the development of osteosarcoma may be associated with extracellular matrix,bone cell differentiation and development,human immune regulation,and collagen synthesis and degradation.Kyoto Encyclopedia of Genes and Genomes enrichment results showed the involvement of pathways such as PI3K-Akt signaling pathway,focal adhesion signaling pathway,and immune response in the onset of osteosarcoma.(3)The intersection analysis revealed a total of 59 key genes.Through Protein-Protein Interaction network analysis,8 hub genes were selected,which were LUM,PLOD1,PLOD2,MMP14,COL11A1,THBS2,LEPRE1,and TGFB1,all of which were upregulated.(4)External validation revealed significantly downregulated miRNAs that regulate the hub genes,with hsa-miR-144-3p and hsa-miR-150-5p showing the most significant downregulation.Text validation results demonstrated that the expression of hub genes was consistent with previous research.(5)Drug sensitivity analysis indicated a negative correlation between the activity of methotrexate,6-mercaptopurine,and pazopanib with the mRNA expression of PLOD1,PLOD2,and MMP14.Moreover,zoledronic acid and lapatinib showed a positive correlation with the mRNA expression of PLOD1,LUM,MMP14,PLOD2,and TGFB1.This suggests that zoledronic acid and lapatinib may be potential therapeutic drugs for osteosarcoma,but further validation is required through additional basic experiments and clinical studies.

ObjectiveTo investigate the mechanism of Acanthopanacis Senticosi Radix et Rhizoma seu Caulis extract （ASH） in treating Parkinson's disease （PD） in mice by Data-Independent Acquisition （DIA） proteomics. MethodsThe α-Synuclein （α-Syn） transgenic PD mice were selected as suitable models for PD， and they were randomly assigned into PD， ASH （61.25 mg·kg^-1）， and Madopar （97.5 mg·kg^-1） groups. Male C57BL/6 mice of the same age were selected as the control group， with eight mice in each group. Mice were administrated with corresponding drugs by gavage once a day for 20 days. The pole climbing time and the number of autonomic activities were recorded to evaluate the exercise ability of mice. Hematoxylin-eosin staining was employed to observe neuronal changes in the substantia nigra of PD mice. Immunohistochemistry （IHC） was employed to measure the tyrosine hydroxylase （TH） activity in the substantia nigra and assess the areal density of α-Syn in the striatum. DIA proteomics was used to compare protein expression in the substantia nigra between groups. IHC was utilized to validate key differentially expressed proteins， including Lactotransferrin， Notch2， Ndrg2， and TMEM 166. The cell counting kit-8 （CCK-8） method was used to investigate the effect of ASH on the viability of PD cells with overexpression of α-Syn. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot were employed to determine the protein and mRNA levels of Lactotransferrin， Notch2， Ndrg2， and TMEM 166 in PD cells. ResultsCompared with the control group， the model group showed prolonged pole climbing time， diminished coordination ability， reduced autonomic activities （P<0.01）， and reduced swelling neurons. Compared with the model group， ASH and Madopar reduced the climbing time， increased autonomic activities （P<0.01）， and ameliorated neuronal damage. Compared with the control group， the model group showed a decrease in TH activity in the substantia nigra and an increase in α-Syn accumulation in the striatum （P<0.01）. Compared with the model group， the ASH group showed an increase in TH activity and a reduction in α-Syn accumulation （P<0.05）. DIA proteomics revealed a total of 464 differentially expressed proteins in the model group compared with the control group， with 323 proteins being up-regulated and 141 down-regulated. A total of 262 differentially expressed proteins were screened in the ASH group compared with the model group， including 85 proteins being up-regulated and 177 down-regulated. Kyoto encylopedia of genes and genomes （KEGG） pathway analysis indicated that ASH primarily regulated the Notch signaling pathway. The model group showed up-regulation in protein levels of Notch2， Ndrg2， and TMEM 166 and down-regulation in the protein level of Lactotransferrin compared with the control group （P<0.01）. Compared with the model group， ASH down-regulated the protein levels of Notch2， Ndrg2， and TMEM 166 （P<0.05） while up-regulating the protein level of Lactotransferrin （P<0.01）. The IHC results corroborated the proteomics findings. The cell experiment results showed that compared with the control group， the modeling up-regulated the mRNA and protein levels of Notch2， Ndrg2， and TMEM 166 （P<0.01）， while down-regulating the mRNA and protein levels of Lactotransferrin （P<0.01）. Compared with the model group， ASH reduced the mRNA and protein levels of Notch2， Ndrg2， and TMEM 166 （P<0.01）， while increasing the mRNA and protein levels of Lactotransferrin （P<0.05， P<0.01）. ConclusionASH may Synergistically inhibit the Notch signaling pathway and mitigate neuronal damage by down-regulating the expression of Notch2 and Ndrg2. Additionally， by up-regulating the expression of Lactotransferrin and down-regulating the expression of TMEM166， ASH can address brain iron accumulation， intervene in ferroptosis， inhibit mitophagy， and mitigate reactive oxygen species damage， thereby protecting nerve cells and contributing to the treatment of PD.

Hearing loss has become increasingly prevalent and causes considerable disability, thus gravely burdening the global economy. Irreversible loss of hair cells is a main cause of sensorineural hearing loss, and currently, the only relatively effective clinical treatments are limited to digital hearing equipment like cochlear implants and hearing aids, but these are of limited benefit in patients. It is therefore urgent to understand the mechanisms of damage repair in order to develop new neuroprotective strategies. At present, how to promote the regeneration of functional hair cells is a key scientific question in the field of hearing research. Multiple signaling pathways and transcriptional factors trigger the activation of hair cell progenitors and ensure the maturation of newborn hair cells, and in this article, we first review the principal mechanisms underlying hair cell reproduction. We then further discuss therapeutic strategies involving the co-regulation of multiple signaling pathways in order to induce effective functional hair cell regeneration after degeneration, and we summarize current achievements in hair cell regeneration. Lastly, we discuss potential future approaches, such as small molecule drugs and gene therapy, which might be applied for regenerating functional hair cells in the clinic.
Infant, Newborn ; Humans ; Hair Cells, Auditory, Inner/physiology* ; Ear, Inner/physiology* ; Hair Cells, Auditory/physiology* ; Regeneration/genetics* ; Stem Cells

Objective To retrospectively analyze the prevention and control effect and epidemic characteristics of elderly tuberculosis in Hubei Province from 2016 to 2020, and to provide a scientific basis for the prevention and treatment of elderly tuberculosis in Hubei Province． Methods The data on tuberculosis patients aged 60 and above who registered their current address in Hubei Province from 2016 to 2020 were collected and analyzed. The registration rates and composition ratios were analyzed using χ² test and χ² test for trend. Results A total of 135 976 tuberculosis patients were reported in Hubei from 2016 to 2020. The annual average registration rate of elderly tuberculosis among the elderly registered residence population (referring to the registration rate of elderly registered residence population aged 60 and above as the denominator, and tuberculosis patients aged 60 and above as the numerator) was 263.51/100 000. The highest rate was 300.02/100,000 in 2017, and the lowest was 188.19/100,000 in 2020 (χ²=70,227.603, P<0.001). In terms of composition, the average annual proportion of tuberculosis patients in the 60-70 years old group was 59.60%, which decreased year by year (χ²_trend=40.448，P<0.001 ). The average annual proportion of males was 73.35%, which was significantly higher than that of females (26.65%). The average annual proportion of farmers was 62.03%. From the perspective of case management, the annual average proportion of major epidemic online reports was 85.17%. The classification of cases was mainly based on clinical diagnosis, accounting for 48.33% annually and showing a decreasing trend year by year (χ²_trend=740.911, P<0.001). The proportion of confirmed cases was 25.08%, which showed an increasing trend (χ²_trend=380.557, P<0.001). From 2016 to 2019, the delay rate of diagnosis and treatment of elder tuberculosis patients was 49.42% (67 876/135 967), and the delay rate decreased year by year (χ²_trend=323.764, P<0.001). Conclusion The elderly population with pulmonary tuberculosis in Hubei Province shows a downward trend. It is necessary to focus on the efforts of designated hospitals to proactively identify cases, increase the proportion of confirmed cases, maintain a high tracking in place, reduce medical delays, and ensure the effectiveness of tuberculosis prevention and treatment for the elderly.

Based on the strategy of metabolomics combined with bioinformatics, this study analyzed the potential allergens and mechanism of pseudo-allergic reactions (PARs) induced by the combined use of Reduning injection and penicillin G injection. All animal experiments and welfare are in accordance with the requirements of the First Affiliated Experimental Animal Ethics and Animal Welfare Committee of Henan University of Chinese Medicine (approval number: YFYDW2020002). Based on UPLC-Q-TOF/MS technology combined with UNIFI software, a total of 21 compounds were identified in Reduning and penicillin G mixed injection. Based on molecular docking technology, 10 potential allergens with strong binding activity to MrgprX2 agonist sites were further screened. Metabolomics analysis using UPLC-Q-TOF/MS technology revealed that 34 differential metabolites such as arachidonic acid, phosphatidylcholine, phosphatidylserine, prostaglandins, and leukotrienes were endogenous differential metabolites of PARs caused by combined use of Reduning injection and penicillin G injection. Through the analysis of the "potential allergen-target-endogenous differential metabolite" interaction network, the chlorogenic acids (such as chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid, and isochlorogenic acid A) and β-lactam allergens in the combination of the two may be mainly regulated by PLD1, PLA2G12A and CYP1A1. The three upstream signal target proteins mainly activate the arachidonic acid metabolic pathway, promote the degranulation of mast cells, release downstream endogenous inflammatory mediators, and induce PARs.

Platycodonis Radix is the dry root of Platycodon grandiflorum of Campanulaceae, which has a variety of pharmacological effects and is a commonly used bulk Chinese medicine. In this study, the chloroplast genome sequences of six P. grandiflorum from different producing areas has been sequenced with Illumina HiSeq X Ten platform. The specific DNA barcodes were screened, and the germplasm resources and genetic diversity were analyzed according to the specific barcodes. The total length of the chloroplast genome of 6 P. grandiflorum samples was 172 260-172 275 bp, and all chloroplast genomes showed a typical circular tetrad structure and encoded 141 genes. The comparative genomics analysis and results of amplification efficiency demonstrated that trnG-UCC and ndhG_ndhF were the potential specific DNA barcodes for identification the germplasm resources of P. grandiflorum. A total of 305 P. grandiflorum samples were collected from 15 production areas in 9 provinces, for which the fragments of trnG-UCC and ndhG_ndhF were amplificated and the sequences were analyzed. The results showed that trnG-UCC and ndhG_ndhF have 5 and 11 mutation sites, respectively, and 5 and 7 haplotypes were identified, respectively. The combined analysis of the two sequences formed 13 haplotypes (named Hap1-Hap13), and Hap4 is the main genotype, followed by Hap1. The unique haplotypes possessed by the three producing areas can be used as DNA molecular tags in this area to distinguish from the germplasm resources of P. grandiflorum from other areas. The haplotype diversity, nucleotide diversity and genetic distance were 0.94, 4.79×10^-3 and 0.000 0-0.020 3, respectively, suggesting that the genetic diversity was abundant and intraspecific kinship was relatively close. This study laid a foundation for the identification of P. grandiflorum, the protection and utilization of germplasm resources, and molecular breeding.

BACKGROUND:The formation of Lewy bodies due to abnormal α-synuclein aggregation is a characteristic pathological change in Parkinson's disease.In recent years,several studies have revealed that the formation of α-synuclein aggregates is closely related to its post-translational modifications.The modification of α-synuclein such as phosphorylation,nitration,acetylation,and ubiquitination has attracted extensive attention in the pathogenesis and progression of Parkinson's disease. OBJECTIVE:To review the research progress in the effect of modification types and sites of α-synuclein on the characteristic pathological formation and progression of Parkinson's disease. METHODS:PubMed and CNKI databases were searched by the first author with the key words of"α-synuclein,Parkinson's disease,phosphorylation,acetylation,ubiquitination,nitration"in English and Chinese respectively to collect and sort out the literature related to abnormal modification of α-synuclein in recent years.Finally,61 articles were included for further review. RESULTS AND CONCLUSION:Abnormal modification of α-synuclein is closely related to its protein structure and its positive and negative charges.Its amino terminus is positively charged and prone to ubiquitination and acetylation modifications.The central hydrophobic region is prone to forming β-pleated sheet due to its hydrophobic property.The carboxyl terminus is negatively charged,which is the main phosphorylation modification region.Phosphorylation modification sites promote phosphorylation modification and are closely related to α-synuclein aggregation,while protein kinases can target the activation of translational modifications,which may help to promote or inhibit aggregate formation.The degradation pathway of α-synuclein mainly plays a role in removing pathological proteins.Various kinase catalysts contribute to impaired protein ubiquitination modifications that lead to abnormal protein accumulation,thereby exacerbating neurodegeneration.The amino-terminal acetylation of α-synuclein improves the shuttle ability of the protein to the cell membrane and slows down the protein aggregation,which may be the protection target of nerve cells.However,the acetylation modification of the mutant protein produces the opposite effect.The protein nitration modification is mainly related to oxidative stress.The aggregation tendency of the protein modified by nitration is enhanced under the action of reactive oxygen species.Different post-translational modifications have different effects.Therefore,elucidating the main mechanisms of their post-translational modifications and inhibiting the post-translational modifications that contribute to protein aggregation may provide a reference for new targets for early diagnosis and treatment of Parkinson's disease.

BACKGROUND:C2 ceramide reduces the formation of Alpha-Synuclein(α-Syn)oligomers as the protein phosphatase 2A agonist,which has an important regulatory effect on cell aging in the central nervous system. OBJECTIVE:To investigate the protective mechanism of C2 ceramide on dopaminergic neurons. METHODS:Twenty-five C57BL/6 mice were randomly divided into control group,model group,C2 ceramide low-,medium-and high-dose groups(n=5 per group).Except for the control group,a mouse model of Parkinson's disease was established by injecting mutant A53T α-Syn oligomers into the left striatum in the other groups.On the 30th day after the striatal injection,three C2 ceramide groups were intragastrically administered with C2 ceramide(1,5,10 μg/g)dissolved in saline at one time,while the control and model groups were administered with the same amount of saline within 30-90 days after modeling,for a total of 60 days.Behavioral changes in each group of mice were observed during this period.On the 90th day after striatal injection,mouse brain tissue was extracted by perfusion under anesthesia,and the changes of dopaminergic neurons in the midbrain substantia nigra were analyzed by immunohistochemical staining.The levels of α-Syn oligomerization and phosphorylation in the midbrain of mice were detected by ELISA,and the changes of enzyme activities related to α-Syn phosphorylation were analyzed. RESULTS AND CONCLUSION:C2 ceramide had an ameliorating effect on Parkinson's disease-like dyskinesia in mice caused by the striatal injection of mutant A53T α-Syn oligomers.High-dose C2 ceramide showed better effects on dyskinesia in mice with Parkinson's disease(P<0.01).The mutant A53T α-Syn oligomers significantly reduced the number of dopaminergic neurons in the substantia nigra of mice(P<0.01),while the number of dopaminergic neurons in the substantia nigra increased significantly in the C2 ceramide high-dose group(P<0.01).The levels of α-Syn oligomers and phosphorylated α-Syn in the brain were significantly reduced in the C2 ceramide high-dose group compared with the model group(P<0.01),while the level of ceramide was increased(P<0.05)and the activity of protein phosphatase 2A was significantly upregulated(P<0.01).To conclude,C2 ceramide can attenuate the neurotoxic effects induced by oligomerized α-Syn by the phosphorylation modification environment of α-Syn in mouse midbrain tissue and protect against the reduction in the number of nigrostriatal dopaminergic neurons in mice,thereby reducing the degree of dyskinesia in Parkinson's disease.