BACKGROUND:Exercise training can improve osteoporosis,but its effects and mechanisms on senile osteoporosis are not fully understood. OBJECTIVE:To observe the effect of treadmill exercise on osteoporosis and wnt/β-catenin signal pathway in aged rats. METHODS:Sixteen 24-month-old male Sprague-Dawley rats were randomly divided into osteoporosis group(n=8)and treadmill group(n=8)and eight 6-month-old male Sprague-Dawley rats were used as young control group.The model of senile osteoporosis was replicated by natural aging and the rats in the treadmill group were treated with treadmill exercise once a day,5 days a week,for 8 weeks.Levels of bone metabolic markers such as type I collagen cross-linked C-terminal peptide,tartrate resistant acid phosphatase,osteocalcin and bone specific alkaline phosphatase were detected by ELISA;bone mineral density of the left femur and L5 was measured by dual energy X-ray;bone scanning and bone microstructure quantitative analysis were performed by bone micro-CT;and the mRNA and protein expression levels of wnt3a,β-catenin,LRP5,DKK1 and GSK3β were detected by RT-PCR and western blot,respectively. RESULTS AND CONCLUSION:Compared with the young control group,the osteoporosis group showed a reduction in serum bone specific alkaline phosphatase and osteocalcin levels(P<0.05),bone mineral density of the femur and L5,the number of tibia and L4 bone trabeculae,bone volume,bone volume fraction(P<0.05),and mRNA and protein expression of wnt3a,β-catenin,and LRP5 in bone marrow tissue(P<0.05)as well as an increase in serum levels of tartrate resistant acid phosphatase and type I collagen cross-linked C-terminal peptide(P<0.05),the intertrabecular space between the tibia and L4,structural model index(P<0.05),and mRNA and protein expression of DKK1 and GSK3 β in bone marrow tissue(P<0.05).In addition to the reduced number of trabeculae in the tibia and L4 vertebrae,the trabeculae were structurally disturbed and sparsely aligned and fractured.Compared with the osteoporosis group,the treadmill group showed an increase in serum bone specific alkaline phosphatase and osteocalcin levels(P<0.05),bone mineral density of the femur and L5(P<0.05),the number of tibial trabeculae,bone volume,bone volume fraction(P<0.05),mRNA and protein expression of wnt3a,β-catenin,and LRP5 in bone marrow tissue(P<0.05)but a reduction in the serum levels of tartrate resistant acid phosphatase and type I collagen cross-linked C-terminal peptide,L4 trabecular space,tibial trabecular space,structural model index,and mRNA and protein expression of DKK1 and GSK3 β in bone marrow tissue(P<0.05).In addition to the increased number of tibial and L4 trabeculae,the trabeculae were arranged in a regular and dense pattern and were connected to a network.To conclude,treadmill exercise may improve osteoporosis in aged rats by activating the wnt/β-catenin signal pathway.

BACKGROUND:Synovitis plays a leading role in the early progression of knee osteoarthritis and is a potential early therapeutic target.However,the mechanism of synovitis remains unclear.In animal models,increased systemic iron and intracellular iron uptake can induce and exacerbate osteoarthritis,but the association with ferroptosis in synovitis remains unclear.Further studies are needed to investigate the role of ferroptosis in the development and progression of synovitis in osteoarthritis. OBJECTIVE:To investigate the role of ferroptosis mediated by glutathione peroxidase 4(GPX4)in the development of synovitis in knee osteoarthritis. METHODS:The synovial tissues of 43 patients with osteoarthritis who underwent arthroscopic or joint replacement surgery and 10 patients undergoing arthroscopic treatment of meniscal injury or ligament tear were collected and divided into three groups according to the Kellgren-Lawrence grading of X-ray images:normal control group(KLG 0,n=10),early knee osteoarthritis group(KLG 1,2,n=20)and late knee osteoarthritis group(KLG 3,4,n=23).Hematoxylin-eosin staining was used to observe the severity of synovitis in each group,and iron deposition in the synovium in each group was evaluated by Prussian blue staining.The expressions of Acyl-CoA Synthetase Long Chain Family Member 4(ACSL4),GPX4,cyclooxygenase 2 and tumor necrosis factor α in the synovium were detected by immunohistochemical staining.Western blot and immunofluorescence were used to detect the expression of ferroptosis-related proteins ACSL4 and GPX4. RESULTS AND CONCLUSION:Compared with the normal control group,iron content in synovial tissue was increased in the knee osteoarthritis groups,and iron deposition in the late knee osteoarthritis group was higher than that in the early osteoarthritis group.ACSL4 was highly expressed in the synovial tissue of knee osteoarthritis compared with the normal control group(P＜0.01),and GPX4 was lowly expressed in the synovial tissue of knee osteoarthritis(P＜0.01).The expression level of ACSL4 increased with the progression of osteoarthritis,while the expression level of GPX4 decreased with the progression of osteoarthritis.The expression of cyclooxygenase 2 in the synovium of osteoarthritis was significantly higher than that in the normal synovium,and the expression was the highest in the early stage of osteoarthritis,which was significantly different from that in the advanced stage of osteoarthritis(P＜0.01).The expression of tumor necrosis factor α in the synovium of osteoarthritis was significantly higher than that in the normal synovium,but there was no significant difference between early and late osteoarthritis groups(P＞0.05).To conclude,the deposition of iron exists in the synovial tissue of osteoarthritis and ferroptosis is involved in the occurrence and progression of synovitis in knee osteoarthritis.

BACKGROUND:There are many treatment methods for knee osteoarthritis,among which electroacupuncture,as an important non-drug treatment,is effective in the treatment of knee osteoarthritis,but its exact mechanism is not clear. OBJECTIVE:Effect of electroacupuncture on the expression of p53 and P21 in articular cartilage and subchondral bone of aged rats with knee osteoarthritis. METHODS:Eight 6-month-old male Sprague-Dawley rats were included in the young group and sixteen 24-month-old male Sprague-Dawley rats were randomly divided into old group(n=8)and electroacupuncture group(n=8).The rats in the electroacupuncture group received electroacupuncture stimulation once a day,5 days a week,for 8 continuous weeks,and the other two groups did not do any treatment.Eight weeks later,the level of type Ⅱ collagen C-terminal peptide in peripheral blood was detected by ELISA,the morphology of left knee cartilage and subchondral bone was observed by safranin O-fast green staining,the degree of knee cartilage degeneration was evaluated by modified Mankin's score,the microstructure of left knee cartilage and subchondral bone was detected by micro-CT,and the expression levels of matrix metalloproteinase 13,P53,P21 Mrna and protein were detected by RT-PCR and western blot respectively. RESULTS AND CONCLUSION:Compared with the young group,the level of C-terminal peptide of type Ⅱ collagen in the peripheral blood was increased in the old group(P<0.05).The micro-CT results showed that the bone volume fraction,bone mineral density and the number of bone trabeculae were decreased in the old group compared with the young group(P<0.05),while the trabecular separation increased(P<0.05).Safranin O-fast green staining showed that in the old group,the surface layer of cartilage was uneven with fissures,the morphology of chondrocytes was irregular and stained unevenly,the boundary between the cartilage and subchondral bone was blurred,and the matrix loss was serious.The Mankin's score was higher in the old group than the young group(P<0.05).The expression of matrix metalloproteinase 13,P53,P21 at Mrna and protein levels increased in the old group compared with the young group(P<0.05).Compared with the old group,electroacupuncture decreased the level of C-terminal peptide of type Ⅱ collagen(P<0.05),increased the bone volume fraction,bone mineral density and the number of bone trabeculae(P<0.05),and decreased the trabecular separation(P<0.05).Safranin O-fast green staining showed that in the electroacupuncture group,the surface of cartilage was smooth and red staining was uniform,and the cell morphology and structure were between the young group and the old group.Following electroacupuncture treatment,the Mankin's score(P<0.05),matrix metalloproteinase 13 and P21 Mrna expression(P<0.05),and matrix metalloproteinase 13 and P53 protein expression decreased(P<0.05),while there was a decreasing trend of P53 Mrna and P21 protein expression,but with no statistical significance(P>0.05).To conclude,electroacupuncture may delay articular cartilage degeneration and subchondral osteoporosis in aged rats by inhibiting the expression of P53 and P21,so as to protect joints and delay joint aging.

BACKGROUND:Inflammation is one of the important factors that induce cerebral ischemia-reperfusion injury.Studies have shown that electroacupuncture can effectively reduce inflammation after ischemic stroke and improve the symptoms of neurological deficits,but the mechanism is not clear. OBJECTIVE:To observe the effect of electroacupuncture on Toll-like receptor 4/nuclear factor-κB in rats with cerebral ischemia-reperfusion injury. METHODS:Forty-eight male Sprague-Dawley rats were randomly divided into sham operation group,model group and electroacupuncture group,with 16 rats in each group.The rat model of cerebral ischemia-reperfusion injury was prepared by middle cerebral artery occlusion.At 24 hours after modeling,the rats in the electroacupuncture group were treated with electroacupuncture,once a day,20 minutes each time,for a total of 5 days.The sham operation group and the model group did not do any intervention.After 5 days of intervention,Longa method was used to evaluate the degree of neurological injury in rats.Triphenyl tetrazolium chloride staining and hematoxylin-eosin staining were used to measure the volume of cerebral infarction and the pathological changes of brain tissue in rats.Serum interleukin-6,interleukin-18 and tumor necrosis factor-α were detected by ELISA.Expressions of Toll-like receptor 4 and nuclear factor-κB in the cerebral cortex at mRNA and protein levels were detected by fluorescence quantitative PCR and western blot,respectively. RESULTS AND CONCLUSION:Compared with the sham operation group,the neurological function scores,serum interleukin-6,interleukin-18,and tumor necrosis factor-α levels,Toll-like receptor 4 and nuclear factor-κB mRNA and protein expression levels were significantly higher in the model group(P＜0.01).Compared with the model group,electroacupuncture significantly reduced the neurological function scores,serum interleukin-6,interleukin-18,and tumor necrosis factor-α levels,Toll-like receptor 4 and nuclear factor-κB mRNA and protein expression levels(P＜0.05,P＜0.01).Compared with the sham operation group,the volume of cerebral infarction in the model group increased significantly(P＜0.01).Compared with the model group,the volume of cerebral infarction in the electroacupuncture group decreased(P＜0.05).In the model group,the arrangement of neurons was disordered,some nerve cells disappeared,nuclei presented with pyknosis and incomplete structure.After electroacupuncture intervention,the degree of neuronal degeneration and neuronal loss in the cerebral cortex of rats were reduced compared with those in the model group.To conclude,electroacupuncture can significantly improve the neurobehavior of rats with cerebral ischemia-reperfusion injury,reduce brain tissue injury,and effectively reduce the level of serum inflammatory factors.The mechanism may be related to the inhibition of Toll-like receptor 4/nuclear factor-κB signaling pathway.

BACKGROUND:Pulsed electromagnetic fields,as an important physical therapy,are exactly effective in the treatment of osteoarthritis,but the mechanism has not been fully clarified. OBJECTIVE:To observe the effect of pulsed electromagnetic field on the degeneration of knee joint cartilage in aged rats. METHODS:Eight 6-month-old Sprague-Dawley rats were selected as the young group and were subjected to normal diet with no treatment.Sixteen 22-month-old Sprague-Dawley rats were randomly divided into old group(n=8)and pulsed electromagnetic field group(n=8).The rats in the pulsed electromagnetic field group were subjected to a pulsed electromagnetic field intervention,once a day,5 days per week for continuous 8 weeks.The rats in the old group were given no treatment.All rats were anesthetized and executed after 8 weeks for the detection of relevant indexes. RESULTS AND CONCLUSION:Compared with the young group,serum type Ⅱ collagen C-terminal peptide level was increased in the old group(P<0.05);compared with the old group,serum type Ⅱ collagen C-terminal peptide level was decreased in the pulsed electromagnetic field group(P<0.05).Micro-CT showed that the bone volume fraction,bone mineral density,and number of bone trabeculae decreased(P<0.05)and the trabecular separation increased(P<0.05)in the tibia of rats in the aged group compared with the young group;and the bone volume fraction,bone density,and number of trabeculae increased(P<0.05)and the trabecular separation decreased(P<0.05)in the tibia of rats in the pulsed electromagnetic field group compared with the aged group.The tibial plateau Safranin O-fast green staining showed that the articular cartilage structure of rats in the aged group was disorganized,and the number of chondrocytes was obviously reduced,and the tidal line could not be distinguished.The above results were improved in the pulsed electromagnetic field group.RT-qPCR and western blot assay showed that the mRNA and protein expression levels of matrix metalloproteinase 1,matrix metalloproteinase 13,P53 and P21 in the articular cartilage and subchondral bone of rats were elevated in the aged group compared with the young group(P<0.05)and decreased in the pulsed electromagnetic field group compared with the old group(P<0.05).To conclude,pulsed electromagnetic fields may improve osteoarthritis in aged rats by inhibiting chondrocyte senescence,alleviating articular cartilage degradation and inhibiting subchondral bone osteoporosis through suppressing the expression of P53/P21.

Treponema pallidum(Tp),a common sexually transmitted pathogen,can infect the fetus via pla-cental vertical transmission,leading to congenital syphilis(CS).This infection results in adverse pregnancy outcomes,such as stillbirth,miscarriage,preterm birth,and fetal growth restriction.However,the exact pathogenesis remains un-clear.Studies indicate that patients with early syphilis primarily exhibit pro-inflammatory immune responses.The Tp has been proven to induce dysfunction in various immune cells and abnormal expression of cytokines,potentially disrupting im-mune tolerance homeostasis and leading to adverse pregnancy outcomes.Grounded in the current understanding of CS and maternal-fetal immunology by scholars both domestically and internationally,this paper provides a comprehensive review of the potential mechanisms of Tp interacting with the cells of the maternal-fetal interface,ultimately leading to adverse pregnancy outcomes.It summarizes the pathogenesis characteristics,clinical manifestations,and maternal-fetal immune responses of CS.

Objective To analyze the effects of agatroban combined with mitochondrial transplantation on endothelial function and hemorheology in mice with cerebral ischemia-reperfusion injury.Methods 50 SPF grade Kunming mice,with 10 as the normal group,38 mices were successfully modeled and divided into a model group of 9,a mitochondrial transplantation group of 9,an Agatroban group of 10,and a combination group of 10.The mitochondrial transplantation group was given exogenous mitochondrial extract,the agatroban group was given agatroban,the combined group was given agatroban combined with mitochondrial transplantation,and the blank group and model group were injected with normal saline.Observation of changes in cerebral infarction volume,pathological morphology of brain tissue,endothelial function,hemorheology,and relative expression of apoptosis related proteins in mice after 7 days of intervention.Results Compared with normal group,cerebral infarction volume ratio,ET-1,whole blood viscosity,plasma viscosity,Caspase-3 and Bax protein expression levels were increased in model group,mitochondrial transplantation group,agatroban group and combined group,while NO level and Bcl-2 protein expression levels were decreased(P<0.05).Compared with the model group,the cerebral infarction volume ratio,ET-1,whole blood viscosity,plasma viscosity,Caspase-3 and Bax protein expressions in the mitochondrial transplantation group,agatroban group and combined group were decreased,and the combined group was lower than the mitochondrial transplantation group and agatroban group,and the NO level and Bcl-2 protein expression were increased.The combined group was higher than that of mitochondrial transplantation group and agatriban group(P<0.05).Conclusion In mice with cerebral ischemia-reperfusion injury,endothelial function injury was improved,hemorheology was regulated,and brain injury was alleviated after agatroban combined with mitochondrial transplantation.

Objective To explore the role of the PPARα/HOXA10 signaling pathway in mediating the effect of adiponectin(APN)for improving endometrial receptivity in a rat model of polycystic ovary syndrome(PCOS).Methods Forty female SD rat models with letrozole-induced PCOS were randomized,with 10 normal rats as the control,into 4 equal groups for treatment with APN alone,APN combined with GW6471(a specific PPARα inhibitor)or the vehicle for 20 days,or no further treatment(PCOS model group).GW6471 treatment(daily dose of 1 mg/kg)and vehicle treatment were initiated on the 11th day following the start of APN treatment,all administered via intraperitoneal injection.The rats were observed for changes in estrous cycle,body weight,ovarian index and morphology,uterine index and morphology,serum hormone levels and lipid metabolism parameters.Endometrial expressions of PPARα and HOXA10 were detected with immunohistochemistry and Western blotting.The development of endometrial pinopodes was observed under electron microscope,and pregnancies of the rats were recorded.Results The rat models of PCOS exhibited obvious estrous cycle disorders with significantly prolonged estrous interval,increased body weight and ovarian index,decreased uterine index,disordered serum hormones and lipid metabolism(P<0.05),and polycystic ovarian changes,and these changes were significantly improved by APN treatment.Endometrial expressions of PPARα and HOXA10 were significantly lowered in PCOS rats and effectively up-regulated after APN treatment,but GW6471 treatment obviously blocked the effect of APN(P<0.05).APN showed strong protective effect against PCOS-induced impairment of endometrial pinopode development,and this effect was obviously attenuated by GW6471.APN also significantly increased the pregnancy rate and embryo number in PCOS rats,while GW6471 obviously reduced the embryo number and caused developmental retardation of the embryos.Conclusion APN can improve endometrial receptivity in PCOS rats by upregulating the PARα/HOXA10 pathway.

Spinal muscular atrophy (SMA) is the most common neuromuscular disease in children, which seriously affects children′s health. At present, gene and molecular modification therapy for SMA have become hot spots. However, there are many uncertainties about when people with SMA should start treatment, how well the drugs can treat, and the prognosis. Therefore, reliable biomarkers for monitoring and evaluation are urgently needed. This review will summarize the progress made in SMA biomarker research in recent years.

Objective To explore the role of the PPARα/HOXA10 signaling pathway in mediating the effect of adiponectin(APN)for improving endometrial receptivity in a rat model of polycystic ovary syndrome(PCOS).Methods Forty female SD rat models with letrozole-induced PCOS were randomized,with 10 normal rats as the control,into 4 equal groups for treatment with APN alone,APN combined with GW6471(a specific PPARα inhibitor)or the vehicle for 20 days,or no further treatment(PCOS model group).GW6471 treatment(daily dose of 1 mg/kg)and vehicle treatment were initiated on the 11th day following the start of APN treatment,all administered via intraperitoneal injection.The rats were observed for changes in estrous cycle,body weight,ovarian index and morphology,uterine index and morphology,serum hormone levels and lipid metabolism parameters.Endometrial expressions of PPARα and HOXA10 were detected with immunohistochemistry and Western blotting.The development of endometrial pinopodes was observed under electron microscope,and pregnancies of the rats were recorded.Results The rat models of PCOS exhibited obvious estrous cycle disorders with significantly prolonged estrous interval,increased body weight and ovarian index,decreased uterine index,disordered serum hormones and lipid metabolism(P<0.05),and polycystic ovarian changes,and these changes were significantly improved by APN treatment.Endometrial expressions of PPARα and HOXA10 were significantly lowered in PCOS rats and effectively up-regulated after APN treatment,but GW6471 treatment obviously blocked the effect of APN(P<0.05).APN showed strong protective effect against PCOS-induced impairment of endometrial pinopode development,and this effect was obviously attenuated by GW6471.APN also significantly increased the pregnancy rate and embryo number in PCOS rats,while GW6471 obviously reduced the embryo number and caused developmental retardation of the embryos.Conclusion APN can improve endometrial receptivity in PCOS rats by upregulating the PARα/HOXA10 pathway.