1.Differences in deltamethrin resistance and kdr gene mutation in Culex tritaeniorhynchus population in and outside the Yellow Sea wetland
Xiao-er ZHANG ; Zhi-ming WU ; Ye TIAN ; Qian CUI ; Yu-qian JI ; Huan WANG ; Shu-juan YANG ; Yi-chao ZHAO ; Yu WANG ; Hua-yu YIN ; Yu DING ; Guo-jin YAN ; Min-sen ZHAO ; Shou-gang ZHANG ; Bing-dong SONG ; Hong-na CHEN ; Jian GAO ; Wei-fang YANG ; Yu-fu ZHANG ; Hui LIU ; Hong-liang CHU
Acta Parasitologica et Medica Entomologica Sinica 2026;33(2):101-107
Objective To gain insights into the biological characteristics of different populations of Culex tritaeniorhynchus within and around the Yellow Sea wetland from the perspective of the occurrence of resistance, we investigated the levels of resistance to deltamethrin and kdr gene mutation in the wetland and its peripheral areas. Methods Specimens were collected from Cx. tritaeniorhynchus populations at two monitoring sites in the Rare Bird National Nature Reserve and Tiaozi Ni Wetland Scenic Area, and also from two populations in Yancheng City and the Liuhe District of Nanjing, and the resistance of these mosquitoes to deltamethrin was determined using the CDC biotest bottle method. For each concentration of deltamethrin assessed, a random subset of exposed specimens was selected for amplification of the kdr gene fragment, followed by Sanger sequencing to identify and analyze resistance-associated mutations. Results The LC50 levels of deltamethrin among mosquitoes from the four populations in Luhe, Yancheng, the Rare Bird National Nature Reserve and the Tiaozi Ni Wetland Scenic Area were 2.048 5, 7.798 2, 3.473 3, and 17.695 5 mg/mL, respectively, with corresponding concentrations of deltamethrin ranging from 0.005 to 5.000,0.050 to 50.000,0.050 to 25.000 and 0.050 to 50.000 mg/mL, respectively. Furthermore, the ranges of the KT50 values were 11.76-107.43, 67.05-216.30,29.77-107.43 and 28.40-329.51 min; the 1-h knockdown rates were 34.58%-99.15%, 9.52%-43.80%, 55.09%-73.01%, and 10.09%-68.07%; and the 24-h mortality rates were 12.15%-67.52%,9.52%-79.56%,13.17%-82.21%, and 11.01%-78.99%, respectively. With respect to kdr gene mutation, we assayed a total of 63,70,59, and 57 mosquitoes for the four populations, for which we detected L1014F mutation frequencies of 14.29%, 35.00%, 20.34%, and 31.58%, respectively, with a majority of these mutations being heterozygous for resistance. In addition, five adult mosquitoes were identified has having synonymous mutations at site 1011[i. e. , AAT(asparagine)mutation to AAC(asparagine)]. Conclusions Our findings revealed the clear resistance of Cx. tritaeniorhynchus to deltamethrin in the Yancheng region of the Yellow Sea wetland, and the resistance phenotype and kdr frequency of Cx. tritaeniorhynchus in the wetland environment were comparable to those of Cx. tritaeniorhynchus in the wetland environment, thereby indicating that the resistance of different populations of Cx. tritaeniorhynchus was homogeneous under the pressure of different insecticide selection within and around the wetland. However, the underlying mechanisms need to be further studied.
2.Research advances in IP3R calcium ion channels and respiratory system-related diseases
Xinyun XIE ; Yan HUANG ; Ao DANG ; Rong HUA ; Jiachun ZHANG ; Zhao YANG
Chongqing Medicine 2025;54(3):770-774
The pathogenesis of respiratory diseases such as chronic obstructive pulmonary disease(COPD),asthma,and pulmonary hypertension remains incompletely understood.However,accumulating evi-dence suggests that calcium ion channels play a critical role in these disorders.As a key second messenger,cal-cium ions regulates diverse physiological and pathological processes.Studies indicate that calcium ion homeo-stasis,including their concentration and distribution and spatial distribution is mediated primarily through ino-sitol 1,4,5-trisphosphate receptor(IP3R)channel.Disruption of this homeostasis may contribute to the devel-opment of COPD,asthma,and other respiratory diseases.Nevertheless,the role of IP3R channels in respirato-ry diseases require further investigation.
3.The 5-HT Descending Facilitation System Contributes to the Disinhibition of Spinal PKCγ Neurons and Neuropathic Allodynia via 5-HT2C Receptors.
Xiao ZHANG ; Xiao-Lan HE ; Zhen-Hua JIANG ; Jing QI ; Chen-Chen HUANG ; Jian-Shuai ZHAO ; Nan GU ; Yan LU ; Qun WANG
Neuroscience Bulletin 2025;41(7):1161-1180
Neuropathic pain, often featuring allodynia, imposes significant physical and psychological burdens on patients, with limited treatments due to unclear central mechanisms. Addressing this challenge remains a crucial unsolved issue in pain medicine. Our previous study, using protein kinase C gamma (PKCγ)-tdTomato mice, highlights the spinal feedforward inhibitory circuit involving PKCγ neurons in gating neuropathic allodynia. However, the regulatory mechanisms governing this circuit necessitate further elucidation. We used diverse transgenic mice and advanced techniques to uncover the regulatory role of the descending serotonin (5-HT) facilitation system on spinal PKCγ neurons. Our findings revealed that 5-HT neurons from the rostral ventromedial medulla hyperpolarize spinal inhibitory interneurons via 5-HT2C receptors, disinhibiting the feedforward inhibitory circuit involving PKCγ neurons and exacerbating allodynia. Inhibiting spinal 5-HT2C receptors restored the feedforward inhibitory circuit, effectively preventing neuropathic allodynia. These insights offer promising therapeutic targets for neuropathic allodynia management, emphasizing the potential of spinal 5-HT2C receptors as a novel avenue for intervention.
Animals
;
Neuralgia/physiopathology*
;
Protein Kinase C/metabolism*
;
Receptor, Serotonin, 5-HT2C/metabolism*
;
Hyperalgesia/physiopathology*
;
Mice, Transgenic
;
Mice
;
Spinal Cord/metabolism*
;
Serotonin/metabolism*
;
Male
;
Neurons/metabolism*
;
Mice, Inbred C57BL
4.Lentivirus-modified hematopoietic stem cell gene therapy for advanced symptomatic juvenile metachromatic leukodystrophy: a long-term follow-up pilot study.
Zhao ZHANG ; Hua JIANG ; Li HUANG ; Sixi LIU ; Xiaoya ZHOU ; Yun CAI ; Ming LI ; Fei GAO ; Xiaoting LIANG ; Kam-Sze TSANG ; Guangfu CHEN ; Chui-Yan MA ; Yuet-Hung CHAI ; Hongsheng LIU ; Chen YANG ; Mo YANG ; Xiaoling ZHANG ; Shuo HAN ; Xin DU ; Ling CHEN ; Wuh-Liang HWU ; Jiacai ZHUO ; Qizhou LIAN
Protein & Cell 2025;16(1):16-27
Metachromatic leukodystrophy (MLD) is an inherited disease caused by a deficiency of the enzyme arylsulfatase A (ARSA). Lentivirus-modified autologous hematopoietic stem cell gene therapy (HSCGT) has recently been approved for clinical use in pre and early symptomatic children with MLD to increase ARSA activity. Unfortunately, this advanced therapy is not available for most patients with MLD who have progressed to more advanced symptomatic stages at diagnosis. Patients with late-onset juvenile MLD typically present with a slower neurological progression of symptoms and represent a significant burden to the economy and healthcare system, whereas those with early onset infantile MLD die within a few years of symptom onset. We conducted a pilot study to determine the safety and benefit of HSCGT in patients with postsymptomatic juvenile MLD and report preliminary results. The safety profile of HSCGT was favorable in this long-term follow-up over 9 years. The most common adverse events (AEs) within 2 months of HSCGT were related to busulfan conditioning, and all AEs resolved. No HSCGT-related AEs and no evidence of distorted hematopoietic differentiation during long-term follow-up for up to 9.6 years. Importantly, to date, patients have maintained remarkably improved ARSA activity with a stable disease state, including increased Functional Independence Measure (FIM) score and decreased magnetic resonance imaging (MRI) lesion score. This long-term follow-up pilot study suggests that HSCGT is safe and provides clinical benefit to patients with postsymptomatic juvenile MLD.
Humans
;
Leukodystrophy, Metachromatic/genetics*
;
Pilot Projects
;
Genetic Therapy/methods*
;
Hematopoietic Stem Cell Transplantation
;
Male
;
Follow-Up Studies
;
Female
;
Lentivirus/genetics*
;
Child
;
Child, Preschool
;
Hematopoietic Stem Cells/metabolism*
;
Cerebroside-Sulfatase/metabolism*
;
Adolescent
5.Changing prevalence and antibiotic resistance profiles of carbapenem-resistant Enterobacterales in hospitals across China:data from CHINET Antimicrobial Resistance Surveillance Program,2015-2021
Wenxiang JI ; Tong JIANG ; Jilu SHEN ; Yang YANG ; Fupin HU ; Demei ZHU ; Yuanhong XU ; Ying HUANG ; Fengbo ZHANG ; Ping JI ; Yi XIE ; Mei KANG ; Chuanqing WANG ; Pan FU ; Yingchun XU ; Xiaojiang ZHANG ; Ziyong SUN ; Zhongju CHEN ; Yuxing NI ; Jingyong SUN ; Yunzhuo CHU ; Sufei TIAN ; Zhidong HU ; Jin LI ; Yunsong YU ; Jie LIN ; Bin SHAN ; Yan DU ; Sufang GUO ; Lianhua WEI ; Fengmei ZOU ; Yunjian HU ; Xiaoman AI ; Chao ZHUO ; Danhong SU ; Dawen GUO ; Jinying ZHAO ; Hua YU ; Xiangning HUANG ; Wen'en LIU ; Yanming LI ; Yan JIN ; Chunhong SHAO ; Xuesong XU ; Chao YAN ; Shanmei WANG ; Yafei CHU ; Lixia ZHANG ; Juan MA ; Shuping ZHOU ; Yan ZHOU ; Lei ZHU ; Jinhua MENG ; Fang DONG ; Zhiyong LÜ ; Fangfang HU ; Han SHEN ; Wanqing ZHOU ; Wei JIA ; Gang LI ; Jinsong WU ; Yuemei LU ; Jihong LI ; Jinju DUAN ; Jianbang KANG ; Xiaobo MA ; Yanping ZHENG ; Ruyi GUO ; Yan ZHU ; Yunsheng CHEN ; Qing MENG ; Shifu WANG ; Xuefei HU ; Hong ZHANG ; Chun WANG ; Wenhui HUANG ; Ruizhong WANG ; Hua FANG ; Bixia YU ; Yong ZHAO ; Ping GONG ; Kaizhen WENG ; Yirong ZHANG ; Jiangshan LIU ; Longfeng LIAO ; Hongqin GU ; Lin JIANG ; Wen HE ; Shunhong XUE ; Jiao FENG ; Chunlei YUE
Chinese Journal of Infection and Chemotherapy 2025;25(4):445-454
Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43%(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38%,9.73%,and 8.47%,respectively.The prevalence of CRE strains in Escherichia coli was 1.99%.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)%,followed by blood(20.88±3.40)%and urine(18.40±3.45)%.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)%.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.
6.Changing distribution and antibiotic resistance profiles of the respiratory bacterial isolates in hospitals across China:data from CHINET Antimicrobial Resistance Surveillance Program,2015-2021
Ying FU ; Yunsong YU ; Jie LIN ; Yang YANG ; Fupin HU ; Demei ZHU ; Yingchun XU ; Xiaojiang ZHANG ; Fengbo ZHANG ; Ping JI ; Yi XIE ; Mei KANG ; Chuanqing WANG ; Pan FU ; Yuanhong XU ; Ying HUANG ; Ziyong SUN ; Zhongju CHEN ; Yuxing NI ; Jingyong SUN ; Yunzhuo CHU ; Sufei TIAN ; Zhidong HU ; Jin LI ; Bin SHAN ; Yan DU ; Sufang GUO ; Lianhua WEI ; Fengmei ZOU ; Hong ZHANG ; Chun WANG ; Yunjian HU ; Xiaoman AI ; Chao ZHUO ; Danhong SU ; Dawen GUO ; Jinying ZHAO ; Hua YU ; Xiangning HUANG ; Wen'en LIU ; Yanming LI ; Yan JIN ; Chunhong SHAO ; Xuesong XU ; Chao YAN ; Shanmei WANG ; Yafei CHU ; Lixia ZHANG ; Juan MA ; Shuping ZHOU ; Yan ZHOU ; Lei ZHU ; Jinhua MENG ; Fang DONG ; Zhiyong LÜ ; Fangfang HU ; Han SHEN ; Wanqing ZHOU ; Wei JIA ; Gang LI ; Jinsong WU ; Yuemei LU ; Jihong LI ; Jinju DUAN ; Jianbang KANG ; Xiaobo MA ; Yanping ZHENG ; Ruyi GUO ; Yan ZHU ; Yunsheng CHEN ; Qing MENG ; Shifu WANG ; Xuefei HU ; Jilu SHEN ; Ruizhong WANG ; Hua FANG ; Bixia YU ; Yong ZHAO ; Ping GONG ; Kaizhen WENG ; Yirong ZHANG ; Jiangshan LIU ; Longfeng LIAO ; Hongqin GU ; Lin JIANG ; Wen HE ; Shunhong XUE ; Jiao FENG ; Chunlei YUE ; Wenhui HUANG
Chinese Journal of Infection and Chemotherapy 2025;25(4):431-444
Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6%of the isolates were Gram-negative bacteria and 17.4%were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)%and(94.0±0.1)%,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P<0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9%.The prevalence of penicillin-resistant S.pneumoniae was 1.4%.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8%and 41.3%,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7%,20.8%,9.4%,29.8%,and 73.3%,respectively.The prevalence of β-lactamase was 96.1%in Moraxella catarrhalis and 60.0%in Haemophilus influenzae.The H.influenzae isolates from children(<18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P<0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.
7.Design and application of a cardiopulmonary resuscitation compression depth limiting device.
Zhifang XUE ; Shuao ZHAO ; Hao LI ; Rongzhao GU ; Rong HUA ; Xianliang YAN
Chinese Critical Care Medicine 2025;37(2):180-182
During cardiopulmonary resuscitation (CPR), the depth of compression is a critical factor affecting the effectiveness of the rescue and the patient's prognosis. However, it is difficult to master the correct compression depth in manual CPR. If the compression depth is too deep, it may cause rib fractures, while insufficient compression depth may fail to establish effective circulation. Although most existing manual CPR compression depth control devices can indicate the depth but lack direct limiting functions. Against this background, led by a team of faculty and students from the Department of Emergency and Rescue Medicine at Xuzhou Medical University, on the basis of the development of a portable CPR protection device (National Invention Patent of China, patent number: ZL 2021 1 0309001.4), the device's compression depth limiting performance was further expanded, and then a new type of CPR compression depth limiting device suitable for different body types was developed. This device has applied for a National Invention Patent of China (patent application number: ZL 2023 1 0644910.2) and has been granted a National Utility Model Patent of China (patent number: ZL 2023 2 1384853.0). The device consists of a horizontal support beam, a vertical sliding beam, a guide block, a rotating shaft, a rotating arm, a limit slider and a limit pin. The horizontal support beams of the two limit devices are fixed horizontally to the horizontal side beams of the portable CPR protection device by bolts, and the connecting arms at the bottom of the vertical sliding beams are fixedly connected with the pressing mechanism, so that precise control of the pressing depth in CPR operation can be realized according to the patient's body size by the mechanical linkage of the vertical sliding beams and the rotating arms, as well as by the blocking and limiting effect of the rotating arms and the guiding blocks on the limiting sliders. It can prevent the occurrence of complications such as chest wall fractures, and thereby increase the success rate of manual CPR, and its structure is simple, low-cost, and suitable for social popularization.
Cardiopulmonary Resuscitation/instrumentation*
;
Humans
;
Equipment Design
;
Pressure
8.International clinical practice guideline on the use of traditional Chinese medicine for functional dyspepsia (2025).
Sheng-Sheng ZHANG ; Lu-Qing ZHAO ; Xiao-Hua HOU ; Zhao-Xiang BIAN ; Jian-Hua ZHENG ; Hai-He TIAN ; Guan-Hu YANG ; Won-Sook HONG ; Yu-Ying HE ; Li LIU ; Hong SHEN ; Yan-Ping LI ; Sheng XIE ; Jin SHU ; Bin-Fang ZENG ; Jun-Xiang LI ; Zhen LIU ; Zheng-Hua XIAO ; Jing-Dong XIAO ; Pei-Yong ZHENG ; Shao-Gang HUANG ; Sheng-Liang CHEN ; Gui-Jun FEI
Journal of Integrative Medicine 2025;23(5):502-518
Functional dyspepsia (FD), characterized by persistent or recurrent dyspeptic symptoms without identifiable organic, systemic or metabolic causes, is an increasingly recognized global health issue. The objective of this guideline is to equip clinicians and nursing professionals with evidence-based strategies for the management and treatment of adult patients with FD using traditional Chinese medicine (TCM). The Guideline Development Group consulted existing TCM consensus documents on FD and convened a panel of 35 clinicians to generate initial clinical queries. To address these queries, a systematic literature search was conducted across PubMed, EMBASE, the Cochrane Library, China National Knowledge Infrastructure (CNKI), VIP Database, China Biology Medicine (SinoMed) Database, Wanfang Database, Traditional Medicine Research Data Expanded (TMRDE), and the Traditional Chinese Medical Literature Analysis and Retrieval System (TCMLARS). The evidence from the literature was critically appraised using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. The strength of the recommendations was ascertained through a consensus-building process involving TCM and allopathic medicine experts, methodologists, pharmacologists, nursing specialists, and health economists, leveraging their collective expertise and empirical knowledge. The guideline comprises a total of 43 evidence-informed recommendations that span a range of clinical aspects, including the pathogenesis according to TCM, diagnostic approaches, therapeutic interventions, efficacy assessments, and prognostic considerations. Please cite this article as: Zhang SS, Zhao LQ, Hou XH, Bian ZX, Zheng JH, Tian HH, Yang GH, Hong WS, He YY, Liu L, Shen H, Li YP, Xie S, Shu J, Zeng BF, Li JX, Liu Z, Xiao ZH, Xiao JD, Zheng PY, Huang SG, Chen SL, Fei GJ. International clinical practice guideline on the use of traditional Chinese medicine for functional dyspepsia (2025). J Integr Med. 2025; 23(5):502-518.
Dyspepsia/drug therapy*
;
Humans
;
Medicine, Chinese Traditional/methods*
;
Practice Guidelines as Topic
;
Drugs, Chinese Herbal/therapeutic use*
9.Protective effect of aliskiren on renal injury in AGT-REN double transgenic hypertensive mice.
Xiao-Ling YANG ; Yan-Yan CHEN ; Hua ZHAO ; Bo-Yang ZHANG ; Xiao-Fu ZHANG ; Xiao-Jie LI ; Xiu-Hong YANG
Acta Physiologica Sinica 2025;77(3):408-418
This study aims to investigate the effects of renin inhibitor aliskiren on kidney injury in human angiotensinogen-renin (AGT-REN) double transgenic hypertensive (dTH) mice and explore its possible mechanism. The dTH mice were divided into hypertension group (HT group) and aliskiren intervention group (HT+Aliskiren group), while wild-type C57BL/6 mice were served as the control group (WT group). Blood pressure data of mice in HT+Aliskiren group were collected after 28 d of subcutaneous penetration of aliskiren (20 mg/kg), and the damage of renal tissue structure and collagen deposition were observed by HE, Masson and PAS staining. The ultrastructure of kidney was observed by transmission electron microscope. Coomassie bright blue staining and biochemical analyzer were used to detect renal function injury. The expression of renin-angiotensin system (RAS) was determined by ELISA and immunohistochemistry. The contents of superoxide dismutase (SOD) and malondialdehyde (MDA) in kidney were determined by chemiluminescence method. The content of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit p47phox, inducible nitric oxide synthase (iNOS), 3-nitrotyrosine (3-NT), NADPH oxidase 2 (NOX2) and NADPH oxidase 4 (NOX4) were detected by Western blot analysis. The results showed that compared with WT group, the blood pressure of mice in HT group was significantly increased. The renal tissue structure in HT group showed glomerular sclerosis, severe interstitial tubular injury, and increased collagen deposition. In addition, 24 h urinary protein, serum creatinine and urea levels increased. Serum and renal tissue levels of angiotensin II (Ang II) were increased, serum angiotensin-(1-7) [Ang-(1-7)] expression was decreased, and renal Ang-(1-7) expression was elevated. The expressions of ACE, Ang II type 1 receptor (AT1R) and MasR in renal tissue were increased, while the expression of ACE2 was decreased. MDA content increased, SOD content decreased, and the expressions of p47phox, iNOS, 3-NT, NOX2 and NOX4 were increased. However, aliskiren reduced blood pressure in dTH mice, improved renal structure and renal function, reduced Ang II and Ang-(1-7) levels in serum and renal tissue, reduced the expression of ACE and AT1R in renal tissue, increased the expression of ACE2 and MasR in renal tissue, and decreased the above levels of oxidative stress indexes in dTH mice. These results suggest that aliskiren may play a protective role in hypertensive renal injury by regulating the balance between ACE-Ang II-AT1R and ACE2-Ang-(1-7)-MasR axes and inhibiting oxidative stress.
Animals
;
Fumarates/therapeutic use*
;
Mice
;
Renin/antagonists & inhibitors*
;
Amides/therapeutic use*
;
Mice, Inbred C57BL
;
Hypertension/physiopathology*
;
Mice, Transgenic
;
Kidney/pathology*
;
Angiotensinogen/genetics*
;
Renin-Angiotensin System/drug effects*
;
NADPH Oxidases/metabolism*
;
Male
;
Antihypertensive Agents/pharmacology*
;
Humans
;
Superoxide Dismutase/metabolism*
;
NADPH Oxidase 4
10.Eccentric treadmill exercise promotes adaptive hypertrophy of gastrocnemius in rats.
Zhi-Qiang DAI ; Yu KE ; Yan ZHAO ; Ying YANG ; Hui-Wen WU ; Hua-Yu SHANG ; Zhi XIA
Acta Physiologica Sinica 2025;77(3):449-464
The present study aimed to investigate the effects of eccentric treadmill exercise on adaptive hypertrophy of skeletal muscle in rats. Thirty-two 3-month-old Sprague Dawley (SD) rats were selected and randomly assigned to one of the four groups based on their body weights: 2-week quiet control group (2C), 2-week downhill running exercise group (2E), 4-week quiet control group (4C), and 4-week downhill running exercise group (4E). The downhill running protocol for rats in the exercise groups involved slope of -16°, running speed of 16 m/min, training duration of 90 min, and 5 training sessions per week. Twenty-four hours after the final session of training, all the four groups of rats underwent an exhaustion treadmill exercise. After resting for 48 h, all the rats were euthanized and their gastrocnemius muscles were harvested for analysis. HE staining was used to measure the cross-sectional area (CSA) and diameter of muscle fibers. Transmission electron microscope was used to observe the ultrastructural changes in muscle fibers. Purithromycin surface labeling translation method was used to measure protein synthesis rate. Immunofluorescence double labeling was used to detect the colocalization levels of lysosomal-associated membrane protein 2 (Lamp2)-leucyl-tRNA synthetase (LARS) and Lamp2-mammalian target of rapamycin (mTOR). Western blot was used to measure the protein expression levels of myosin heavy chain (MHC) IIb and LARS, as well as the phosphorylation levels of mTOR, p70 ribosomal protein S6 kinase (p70S6K), and eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1). The results showed that, compared with the 2C group rats, the 2E group rats showed significant increases in wet weight of gastrocnemius muscle, wet weight/body weight ratio, running distance, running time, pre- and post-exercise blood lactate levels, myofibrillar protein content, colocalization levels of Lamp2-LARS and Lamp2-mTOR, and LARS protein expression. Besides these above changes, compared with the 4C group, the 4E group further exhibited significantly increased fiber CSA, fiber diameter, protein synthesis rate, and phosphorylation levels of mTOR, p70S6K, and 4E-BP1. Compared with the quiet control groups, the exercise groups exhibited ultrastructural damage of rat gastrocnemius muscle, which was more pronounced in the 4E group. These findings suggest that eccentric treadmill exercise may promote mTOR translocation to lysosomal membrane, activating mTOR signaling via up-regulating LARS expression. This, in turn, increases protein synthesis rate through the mTOR-p70S6K-4E-BP1 signaling pathway, promoting protein deposition and inducing adaptive skeletal muscle hypertrophy. Although the ultrastructural changes of skeletal muscle are more pronounced, the relatively long training cycles during short-term exercise periods have a more significant effect on promoting gastrocnemius muscle protein synthesis and adaptive hypertrophy.
Animals
;
Rats, Sprague-Dawley
;
Physical Conditioning, Animal/physiology*
;
Rats
;
Muscle, Skeletal/metabolism*
;
TOR Serine-Threonine Kinases/metabolism*
;
Male
;
Hypertrophy
;
Adaptation, Physiological/physiology*
;
Adaptor Proteins, Signal Transducing/metabolism*
;
Ribosomal Protein S6 Kinases, 70-kDa/metabolism*
;
Intracellular Signaling Peptides and Proteins


Result Analysis
Print
Save
E-mail