BACKGROUND:Skeletal muscle aging is associated with various chronic diseases.Exercise is considered an important means to delay this process,but the multimechanism regulation of exercise intervention strategies still requires in-depth exploration.OBJECTIVE:To systematically outline the main physiological changes in skeletal muscle aging and explore the multiple mechanisms by which exercise regulates these changes,thereby providing a theoretical basis for basic research and clinical applications.METHODS:By searching databases such as Web of Science,PubMed,Embase,CNKI,WanFang,and VIP,relevant literature from database inception to October 2024 was retrieved by the first author,including original research articles and reviews.The search terms were"skeletal muscle aging,sarcopenia,exercise regulation,physical activity,chronic inflammation,inflammaging,mitochondrial dysfunction,extracellular matrix fibrosis,lipid mediators,satellite cells"in English and Chinese.Literature was screened based on inclusion and exclusion criteria,and the included 95 articles underwent quality assessment and data extraction.RESULTS AND CONCLUSION:(1)The core manifestations of skeletal muscle aging are the decline in muscle mass,strength,and function,closely related to various physiological changes.The decreased protein synthesis capacity and accelerated degradation rate in muscles lead to muscle atrophy and functional decline.Additionally,dysfunction of satellite cells is considered a key factor in the reduced regenerative capacity of muscles.Mitochondrial dysfunction is another important factor leading to muscle fatigue and energy metabolism disorders,directly affecting the metabolic activity and endurance of skeletal muscles.Chronic inflammatory responses and extracellular matrix fibrosis further exacerbate muscle aging.These factors interact synergistically,collectively resulting in skeletal muscle degeneration.(2)Exercise is widely recognized as an important means to delay skeletal muscle aging.Exercise alleviates chronic low-grade inflammatory responses in skeletal muscle by regulating the immune system,increasing the secretion of anti-inflammatory factors,and inhibiting the expression of pro-inflammatory factors,thereby mitigating the damage of inflammation to muscles.Exercise also enhances mitochondrial biogenesis and function,improves the muscle's energy metabolism capacity,and consequently increases endurance and strength.Furthermore,exercise regulates lipid metabolism and the synthesis of lipid mediators,reduces fat accumulation and alleviates fat-induced inflammatory responses,thereby further protecting skeletal muscles.The mechanical stimulation from exercise promotes the remodeling of the extracellular matrix,reduces fibrosis occurrence,and improves muscle structure and function.Additionally,exercise activates satellite cells,enhancing the regenerative capacity of skeletal muscles,especially notable with strength training and high-intensity interval training.(3)Future research should include large-scale,multicenter clinical trials to evaluate the comprehensive effects of long-term exercise interventions on skeletal muscle aging.By analyzing data from genomics,metabolomics,and other fields,exploring individual differences in responses to exercise interventions can provide more precise theoretical bases for personalized exercise strategies.Besides exercise,the impacts of other interventions such as nutritional supplementation and pharmacological treatments on skeletal muscle aging should not be overlooked.Future studies can explore the combined use of exercise with these interventions to achieve more significant effects.

BACKGROUND:Skeletal muscle aging is associated with various chronic diseases.Exercise is considered an important means to delay this process,but the multimechanism regulation of exercise intervention strategies still requires in-depth exploration.OBJECTIVE:To systematically outline the main physiological changes in skeletal muscle aging and explore the multiple mechanisms by which exercise regulates these changes,thereby providing a theoretical basis for basic research and clinical applications.METHODS:By searching databases such as Web of Science,PubMed,Embase,CNKI,WanFang,and VIP,relevant literature from database inception to October 2024 was retrieved by the first author,including original research articles and reviews.The search terms were"skeletal muscle aging,sarcopenia,exercise regulation,physical activity,chronic inflammation,inflammaging,mitochondrial dysfunction,extracellular matrix fibrosis,lipid mediators,satellite cells"in English and Chinese.Literature was screened based on inclusion and exclusion criteria,and the included 95 articles underwent quality assessment and data extraction.RESULTS AND CONCLUSION:(1)The core manifestations of skeletal muscle aging are the decline in muscle mass,strength,and function,closely related to various physiological changes.The decreased protein synthesis capacity and accelerated degradation rate in muscles lead to muscle atrophy and functional decline.Additionally,dysfunction of satellite cells is considered a key factor in the reduced regenerative capacity of muscles.Mitochondrial dysfunction is another important factor leading to muscle fatigue and energy metabolism disorders,directly affecting the metabolic activity and endurance of skeletal muscles.Chronic inflammatory responses and extracellular matrix fibrosis further exacerbate muscle aging.These factors interact synergistically,collectively resulting in skeletal muscle degeneration.(2)Exercise is widely recognized as an important means to delay skeletal muscle aging.Exercise alleviates chronic low-grade inflammatory responses in skeletal muscle by regulating the immune system,increasing the secretion of anti-inflammatory factors,and inhibiting the expression of pro-inflammatory factors,thereby mitigating the damage of inflammation to muscles.Exercise also enhances mitochondrial biogenesis and function,improves the muscle's energy metabolism capacity,and consequently increases endurance and strength.Furthermore,exercise regulates lipid metabolism and the synthesis of lipid mediators,reduces fat accumulation and alleviates fat-induced inflammatory responses,thereby further protecting skeletal muscles.The mechanical stimulation from exercise promotes the remodeling of the extracellular matrix,reduces fibrosis occurrence,and improves muscle structure and function.Additionally,exercise activates satellite cells,enhancing the regenerative capacity of skeletal muscles,especially notable with strength training and high-intensity interval training.(3)Future research should include large-scale,multicenter clinical trials to evaluate the comprehensive effects of long-term exercise interventions on skeletal muscle aging.By analyzing data from genomics,metabolomics,and other fields,exploring individual differences in responses to exercise interventions can provide more precise theoretical bases for personalized exercise strategies.Besides exercise,the impacts of other interventions such as nutritional supplementation and pharmacological treatments on skeletal muscle aging should not be overlooked.Future studies can explore the combined use of exercise with these interventions to achieve more significant effects.

Objective:To explore the short-term effect of drug-coated balloon angioplasty (DCBA) and common plain old balloon angioplasty (POBA) in the isolated popliteal artery chronic total occlusion (CTO), and to analyze the factors affecting the postoperative primary patency rate.Methods:A retrospective cohort study approach was used in this study. A total of 42 isolated popliteal CTO patients admitted to the First Affiliated Hospital of Bengbu Medical University from January 2020 to June 2022 were divided into two groups according to their different balloons: 24 as POBA group and 18 as DCBA group. The primary patency rate of target lesions, the clinically-driven target lesion revascularization(CD-TLR) rate, amputation and toe amputation rate, and the improvement of ankle-brachial index (ABI) and Rutherford grade at 6 and 12 months after surgery were compared.Measurement data with normal distribution was expressed as xˉ± s and means between two groups were compared using independent samples t-test. The percentage of counting data was calculated, and the rate between groups was compared by χ2 test or Fisher's exact probability method. Kaplan-Meier survival curve method was used to plot the survival curves of primary patency rate and CD-TLR free rate at 12 months after surgery, and Log rank test was used to compare the differences between groups . Univariate log rank test and multivariate Cox regression was used to analyze the factors affecting the primary patency rate at 12 months in patients with isolated popliteal CTO. Results:12 months after surgery, 4 patients in the DCBA group experienced lumen restenosis or occlusion while 12 patients in the POBA group experienced lumen restenosis or occlusion. The cumulative primary patency rate of target lesions in the DCBA group was higher than that in the POBA group (Log-rank χ2=4.03, P=0.045). ABI in the DCBA group at 6 and 12 months was greater than that in the POBA group [(0.91±0.11) vs (0.83±0.09), (0.84±0.11) vs (0.70±0.12), t=2.40, P=0.021, t=3.64 and P=0.001].There were no significant difference in cumulative CD-TLR exemption, amputation and amputation at 12 months, and Rutherford grade at 6 and 12 months for both groups(all P>0.05). The results of univariate analysis showed that DCBA as surgical method, hypertension and coronary heart disease were the influencing factors of the primary patency rate after chronic occlusion of the isolated popliteal artery (all P<0.05). The results of multivariate Cox regression analysis indicated that DCBA as surgical method was a protective factor for primary patency at 12 months (odds ratio =0.31,95% confidence interval: 0.10~0.870., P=0.038), while hypertension was an independent risk factor( OR=5.63,95% confidence interval: 1.54~20.56, P=0.009). Conclusions:The cumulative primary patency rate of target lesions 12 months after isolated popliteal CTO was higher than that of POBA. DCBA as surgical method was a protective factor for primary patency rate 12 months in patients with isolated popliteal CTO, while hypertension was an independent risk factor.

ObjectiveTo explore the pharmacological mechanism involved in the treatment of allergic cough （AC） by Xiaoer Huatan Zhike granules （XEHT） based on proteomics and network pharmacology. MethodsAfter sensitization by intraperitoneal injection of 1 mL suspension containing 2 mg ovalbumin （OVA） and 100 mg aluminum hydroxide， a guinea pig model of allergic cough was constructed by nebulization with 1% OVA. The modeled guinea pigs were randomized into the model， low-， medium- and high-dose （1， 5， 20 g·kg^-1， respectively） XEHT， and sodium montelukast （1 mg·kg^-1） groups （n=6）， and another 6 guinea pigs were selected as the blank group. The guinea pigs in drug administration groups were administrated with the corresponding drugs by gavage， and those in the blank and model groups received the same volume of normal saline by gavage， 1 time·d^-1. After 10 consecutive days of drug administration， the guinea pigs were stimulated by 1% OVA nebulization， and the coughs were observed. The pathological changes in the lung tissue were observed by hematoxylin-eosin staining. The enzyme-linked immunosorbent assay was performed to measure the levels of C-reactive protein （CRP）， interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， superoxide dismutase （SOD）， and malondialdehyde （MDA） in the bronchoalveolar lavage fluid （BALF） and immunoglobulin G （IgG） and immunoglobulin A （IgA） in the serum. Immunohistochemistry （IHC） was employed to observe the expression of IL-6 and TNF-α in the lung tissue. Transmission electron microscopy was employed observe the alveolar type Ⅱ epithelial cell ultrastructure. Real-time PCR was employed to determine the mRNA levels of IL-6， interleukin-1β （IL-1β）， and TNF-α in the lung tissue. Label-free proteomics was used to detect the differential proteins among groups. Network pharmacology was used to predict the targets of XEHT in treating AC. The Kyoto Encyclopedia of Genes and Genomes （KEGG） enrichment analysis was performed to search for the same pathways from the results of proteomics and network pharmacology. ResultsCompared with the blank group， the model group showed increased coughs （P<0.01）， elevated levels of CRP， TNF-α， IL-6， and MDA and lowered level of SOD in the BALF （P<0.05， P<0.01）， elevated levels of IgA and IgG in the serum （P<0.05， P<0.01）， congestion of the lung tissue and infiltration of inflammatory cells， increased expression of IL-6 and TNF-α （P<0.01）， large areas of low electron density edema in type Ⅱ epithelial cells， obvious swelling and vacuolization of the organelles， karyopyknosis or sparse and dissolved chromatin， and up-regulated mRNA levels of IL-6， IL-1β， and TNF-α （P<0.01）. Compared with the model group， the drug administration groups showed reduced coughs （P<0.01）， lowered levels of CRP， TNF-α， IL-6， and MDA and elevated level of SOD in the BALF （P<0.05， P<0.01）， alleviated lung tissue congestion， inflammatory cell infiltration， and type Ⅱ epithelial cell injury， and decreased expression of IL-6 and TNF-α （P<0.01）. In addition， the medium-dose XEHT group and the montelukast sodium group showcased lowered serum levels of IgA and IgG （P<0.05， P<0.01）. The medium- and high-dose XEHT groups and the montelukast sodium showed down-regulated mRNA levels of IL-6， IL-1β， and TNF-α and the low-dose XEHT group showed down-regulated mRNA levels of IL-6 and TNF-α （P<0.05， P<0.01）. Phospholipase D， mammalian target of rapamycin （mTOR）， and epidermal growth factor receptor family of receptor tyrosine kinase （ErbB） signaling pathways were the common pathways predicted by both proteomics and network pharmacology. ConclusionProteomics combined with network pharmacology reveal that XEHT can ameliorate AC by regulating the phospholipase D， mTOR， and ErbB signaling pathways.

Objective:To investigate the correlation between postoperative spinal sagittal parameters and reinforced vertebral recompression fractures in patients with osteoporotic vertebral compression fractures (OVCFs) who have undergone percutaneous kyphoplasty (PKP).Methods:Data on patients with OVCFs treated with PKP at the Department of Orthopaedics, Second Affiliated Hospital of Soochow University, from August 2020 to August 2024, were collected. Among these, 31 patients who underwent single-segment PKP experienced postoperative reinforced vertebral recompression fractures (recompression fracture group), comprising 8 males and 23 females, with a mean age of 73.74±8.76 years, a body mass index (BMI) of 23.83±1.87 kg/m 2, and a bone mineral density T-value of -2.29±0.55. The remission rate of the visual analogue scale (VAS) after surgery was 80.14%±4.86%, with a mean volume of bone cement used at 5.37±0.69 ml. The surgical segments involved included T 5 (1 case), T 8 (1 case), T 10 (1 case), T 11 (4 cases), T 12 (9 cases), L 1 (7 cases), L 2 (4 cases), L 3 (2 cases), and L 4 (2 cases). Following a 1∶1 matching principle, 31 patients whose vertebrae did not experience reinforced recompression fractures during the same period (non-recompression fracture group) were included. This group also comprised 8 males and 23 females, with a mean age of 74.88±8.31 years, a BMI of 23.15±2.04 kg/m 2, a bone mineral density T-value of -2.76±0.64, and a VAS remission rate of 79.75%±5.01%. The mean volume of bone cement used in this group was 5.41±0.72 ml. The surgical segments involved included T 8 (1 case), T 10 (1 case), T 11 (4 cases), T 12 (8 cases), L 1 (7 cases), L 2 (5 cases), L 3 (2 cases), L 4 (2 cases), and L 5 (1 case). There were no statistically significant differences in the aforementioned indicators between the two patient groups ( P>0.05). A comparison of the postoperative spinal sagittal parameters between the two groups was conducted, focusing on the local kyphosis angle (LKA), lumbar lordosis (LL), thoracic kyphosis (TK), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and the lumbar-pelvic matching value (PI-LL). Indicators that exhibited statistically significant differences were included in the binary logistic regression analysis to evaluate the impact of spinal sagittal parameters following PKP on the recompression of the reinforced vertebral. Results:The time to reinforced vertebral recompression fractures after PKP ranged from 35 to 184 d, with a median of 69 d. The TK in the recompression fracture group (46.56°±7.02°) was significantly greater than that in the non-recompression fracture group (41.95°±5.76°). Additionally, the LKA, PI and SS were all smaller in the recompression fracture group (9.84°±2.13°, 41.36°±4.27°, 22.69°±5.53°, respectively) compared to the non-recompression fracture group (12.37°±2.64°, 48.09°±6.33°, 28.41°±7.64°), with all differences being statistically significant ( P<0.05). However, no significant differences were observed between the LL, PT, and PI-LL values ( P>0.05). TK, LKA, PI, and SS were included in the binary logistic regression analysis, which indicated that TK [ OR=1.533, 95% CI(1.47, 1.59)] after PKP was positively correlated with the occurrence of reinforced vertebral recompression fractures. Conversely, LKA [ OR=0.882, 95% CI(0.80, 0.96)], PI [ OR=0.815, 95% CI(0.71, 0.91)], and SS [ OR=0.833, 95% CI(0.73, 0.93)] were negatively correlated. Conclusions:The incidence of reinforced vertebral recompression fractures following PKP is associated with spinal sagittal parameters, including TK, LKA, PI, and SS. Specifically, a larger TK and smaller values of LKA, PI, and SS are correlated with an elevated risk of reinforced vertebral recompression fractures.

Objective:To investigate the correlation between postoperative spinal sagittal parameters and reinforced vertebral recompression fractures in patients with osteoporotic vertebral compression fractures (OVCFs) who have undergone percutaneous kyphoplasty (PKP).Methods:Data on patients with OVCFs treated with PKP at the Department of Orthopaedics, Second Affiliated Hospital of Soochow University, from August 2020 to August 2024, were collected. Among these, 31 patients who underwent single-segment PKP experienced postoperative reinforced vertebral recompression fractures (recompression fracture group), comprising 8 males and 23 females, with a mean age of 73.74±8.76 years, a body mass index (BMI) of 23.83±1.87 kg/m 2, and a bone mineral density T-value of -2.29±0.55. The remission rate of the visual analogue scale (VAS) after surgery was 80.14%±4.86%, with a mean volume of bone cement used at 5.37±0.69 ml. The surgical segments involved included T 5 (1 case), T 8 (1 case), T 10 (1 case), T 11 (4 cases), T 12 (9 cases), L 1 (7 cases), L 2 (4 cases), L 3 (2 cases), and L 4 (2 cases). Following a 1∶1 matching principle, 31 patients whose vertebrae did not experience reinforced recompression fractures during the same period (non-recompression fracture group) were included. This group also comprised 8 males and 23 females, with a mean age of 74.88±8.31 years, a BMI of 23.15±2.04 kg/m 2, a bone mineral density T-value of -2.76±0.64, and a VAS remission rate of 79.75%±5.01%. The mean volume of bone cement used in this group was 5.41±0.72 ml. The surgical segments involved included T 8 (1 case), T 10 (1 case), T 11 (4 cases), T 12 (8 cases), L 1 (7 cases), L 2 (5 cases), L 3 (2 cases), L 4 (2 cases), and L 5 (1 case). There were no statistically significant differences in the aforementioned indicators between the two patient groups ( P>0.05). A comparison of the postoperative spinal sagittal parameters between the two groups was conducted, focusing on the local kyphosis angle (LKA), lumbar lordosis (LL), thoracic kyphosis (TK), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and the lumbar-pelvic matching value (PI-LL). Indicators that exhibited statistically significant differences were included in the binary logistic regression analysis to evaluate the impact of spinal sagittal parameters following PKP on the recompression of the reinforced vertebral. Results:The time to reinforced vertebral recompression fractures after PKP ranged from 35 to 184 d, with a median of 69 d. The TK in the recompression fracture group (46.56°±7.02°) was significantly greater than that in the non-recompression fracture group (41.95°±5.76°). Additionally, the LKA, PI and SS were all smaller in the recompression fracture group (9.84°±2.13°, 41.36°±4.27°, 22.69°±5.53°, respectively) compared to the non-recompression fracture group (12.37°±2.64°, 48.09°±6.33°, 28.41°±7.64°), with all differences being statistically significant ( P<0.05). However, no significant differences were observed between the LL, PT, and PI-LL values ( P>0.05). TK, LKA, PI, and SS were included in the binary logistic regression analysis, which indicated that TK [ OR=1.533, 95% CI(1.47, 1.59)] after PKP was positively correlated with the occurrence of reinforced vertebral recompression fractures. Conversely, LKA [ OR=0.882, 95% CI(0.80, 0.96)], PI [ OR=0.815, 95% CI(0.71, 0.91)], and SS [ OR=0.833, 95% CI(0.73, 0.93)] were negatively correlated. Conclusions:The incidence of reinforced vertebral recompression fractures following PKP is associated with spinal sagittal parameters, including TK, LKA, PI, and SS. Specifically, a larger TK and smaller values of LKA, PI, and SS are correlated with an elevated risk of reinforced vertebral recompression fractures.

Objective:To explore the short-term effect of drug-coated balloon angioplasty (DCBA) and common plain old balloon angioplasty (POBA) in the isolated popliteal artery chronic total occlusion (CTO), and to analyze the factors affecting the postoperative primary patency rate.Methods:A retrospective cohort study approach was used in this study. A total of 42 isolated popliteal CTO patients admitted to the First Affiliated Hospital of Bengbu Medical University from January 2020 to June 2022 were divided into two groups according to their different balloons: 24 as POBA group and 18 as DCBA group. The primary patency rate of target lesions, the clinically-driven target lesion revascularization(CD-TLR) rate, amputation and toe amputation rate, and the improvement of ankle-brachial index (ABI) and Rutherford grade at 6 and 12 months after surgery were compared.Measurement data with normal distribution was expressed as xˉ± s and means between two groups were compared using independent samples t-test. The percentage of counting data was calculated, and the rate between groups was compared by χ2 test or Fisher's exact probability method. Kaplan-Meier survival curve method was used to plot the survival curves of primary patency rate and CD-TLR free rate at 12 months after surgery, and Log rank test was used to compare the differences between groups . Univariate log rank test and multivariate Cox regression was used to analyze the factors affecting the primary patency rate at 12 months in patients with isolated popliteal CTO. Results:12 months after surgery, 4 patients in the DCBA group experienced lumen restenosis or occlusion while 12 patients in the POBA group experienced lumen restenosis or occlusion. The cumulative primary patency rate of target lesions in the DCBA group was higher than that in the POBA group (Log-rank χ2=4.03, P=0.045). ABI in the DCBA group at 6 and 12 months was greater than that in the POBA group [(0.91±0.11) vs (0.83±0.09), (0.84±0.11) vs (0.70±0.12), t=2.40, P=0.021, t=3.64 and P=0.001].There were no significant difference in cumulative CD-TLR exemption, amputation and amputation at 12 months, and Rutherford grade at 6 and 12 months for both groups(all P>0.05). The results of univariate analysis showed that DCBA as surgical method, hypertension and coronary heart disease were the influencing factors of the primary patency rate after chronic occlusion of the isolated popliteal artery (all P<0.05). The results of multivariate Cox regression analysis indicated that DCBA as surgical method was a protective factor for primary patency at 12 months (odds ratio =0.31,95% confidence interval: 0.10~0.870., P=0.038), while hypertension was an independent risk factor( OR=5.63,95% confidence interval: 1.54~20.56, P=0.009). Conclusions:The cumulative primary patency rate of target lesions 12 months after isolated popliteal CTO was higher than that of POBA. DCBA as surgical method was a protective factor for primary patency rate 12 months in patients with isolated popliteal CTO, while hypertension was an independent risk factor.

The functional role of glutamatergic (vGluT2) neurons in the pedunculopontine nucleus (PPN) in modulating motor activity remains controversial. Here, we demonstrated that the activity of vGluT2 neurons in the rostral PPN is correlated with locomotion and ipsilateral head-turning. Beyond these motor functions, we found that these rostral PPN-vGluT2 neurons remarkably respond to salient stimuli. Furthermore, we systematically traced the upstream and downstream projections of these neurons and identified two downstream projections from these neurons to the caudal pontine reticular nucleus/anterior gigantocellular reticular nucleus (PnC/GiA) and the zona incerta (ZI). Our findings indicate that the projections to the PnC/GiA inhibit movement, consistent with 'pause-and-play' behavior, whereas those to the ZI promote locomotion, and others respond to a new 'pause-switch-play' pattern. Collectively, these findings elucidate the multifaceted influence of the PPN on motor functions and provide a robust theoretical framework for understanding its physiological and potential therapeutic implications.
Pedunculopontine Tegmental Nucleus/physiology* ; Animals ; Neural Pathways/physiology* ; Vesicular Glutamate Transport Protein 2/metabolism* ; Locomotion/physiology* ; Glutamic Acid/metabolism* ; Neurons/physiology* ; Male ; Mice ; Motor Activity/physiology* ; Zona Incerta/physiology*

ObjectiveTo explore the possible mechanism of Osteoking （OK） on postmenopausal osteoporosis （PMOP）. MethodForty adult female mice were randomly divided into a sham operation （Sham） group， osteoporosis model （OVX） group， estradiol intervention （E₂） group， and OK group， with 10 mice in each group. The modeling was completed by conventional back double incision ovariectomy， and the corresponding drugs were given one week later. After 12 weeks， the body mass and uterine index of mice were measured， and the pathological changes of bone tissue and the number of osteoclasts （OCs） were determined by hematoxylin-eosin （HE） and tartrate-resistant acid phosphatase （TRAP） staining， respectively. Bone mineral density （BMD）， trabecular number （Tb.N）， trabecular separation （Tb.Sp）， and bone volume fraction （BV/TV） were measured by microcomputed tomography （Micro-CT）. The maximum load of the femur was detected by a three-point bending test. The contents of tumor necrosis factor-α （TNF-α） and bone resorption marker C-terminal telopeptide of type Ⅰ collagen （CTX-1） were measured by enzyme linked immunosorbent assay （ELISA）. The protein expression levels of nuclear factor-kappa B p65 （NF-κB p65）， phosphorylated nuclear factor-kappa B p65 （p-NF-κB p65）， nuclear factor kappa B inhibitor alpha （IκBα）， phosphorylated nuclear factor kappa B alpha （p-IκBα）， nuclear factor of activated T cells 1 （NFATc1）， and proto-oncogene （c-Fos） were detected by Western blot. The mRNA expressions of OCs-related specific genes matrix metalloproteinase-9 （MMP-9）， NFATc1， TRAP， cathepsin K （CTSK）， and c-Fos were detected by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. ResultCompared with the Sham group， the uterine index decreased significantly in the OVX group， and the body mass （BMI） increased significantly. The structure of bone trabeculae was completely damaged， and the number of OCs increased. BMD， Tb.N， BV/TV， and maximum load decreased， while Tb.Sp was up-regulated. The levels of TNF-α and CTX-1 in serum were up-regulated. The protein expressions of c-Fos， p-NF-κB p65/NF-κB p65， NFATc1， and p-IκBα/IκBα were increased. The mRNA expressions of NFATc1， c-Fos， CTSK， TRAP， and MMP-9 were up-regulated （P<0.05， P<0.01）. Compared with the OVX group， the body mass of the OK and E₂ groups decreased， and the uterine index increased. The bone trabeculae increased， and the number of OCs decreased. BMD， Tb.N， BV/TV， and maximum load increased， while Tb.Sp decreased. The levels of TNF-α and CTX-1 in serum were decreased. The protein expressions of c-Fos， p-NF-κB p65/NF-κB p65， NFATc1， and p-IκBα/IκBα were decreased， and the mRNA expressions of NFATc1， c-Fos， CTSK， TRAP， and MMP-9 were decreased （P<0.05， P<0.01）. ConclusionOK can inhibit the NF-κB/NFATc1 signaling pathway and reduce bone mass loss by reducing the level of inflammatory injury factors in PMOP mice， which is one of the mechanisms for treating PMOP.

Objective:To summarize the clinical and genetic characteristics of children with β-ketothiolase deficiency (BKTD).Methods:The clinical characteristics, biochemical, markers detected by tandem mass spectrometry (MS/MS) and gas chromatography-mass spectrometry (GC/MS), as well as the variants in ACAT1 gene among 5 children with BKTD in Children′s Hospital of Chongqing Medical University between October 2018 and December 2022 were retrospectively analyzed.Results:The onset age of the disease in 5 patients (4 males and 1 female) ranged from 9.7 to 28.0 months. During the acute phase, severe metabolic acidosis was observed with a pH of 6.9-7.1, as well as hypoglycaemia (2.3-3.4 mmol/L) and positive urinary ketone bodies (+-++++). Blood levels of methylcrotonyl carnitine, methylmalonyl carnitine and malonyl carnitine were 0.03-0.42, 0.34-1.43 and 0.83-3.53 μmol/L respectively and were significantly elevated. Urinary 2-methyl-3-hydroxybutyric acid was 22-202 and 3-hydroxybutyric acid was 4-6 066, both were higher than the normal levels. Methylcrotonylglycine was mild elevated (0-29). The metabolites detected by MS/MS and GC/MS were significantly reduced after treatment. Analysis of ACAT1 gene mutation was performed in 5 children. Most variants were missense (8/9). Four previously unreported variants were identified: c.678G>T (p.Trp226Cys), c.302A>G (p.Gln101Arg), c.627_629dupTGA (p.Asn209_Glu210insAsp) and c.316C>T (p.Gln106Ter), the first 2 variants were predicted to be damaging by SIFT, PolyPhen-2 and Mutation Taster software. c.316C>T (p.Gln106Ter) is a nonsense variant.Conclusions:β-ketothiolase deficiency is relatively rare, lacks specific clinical manifestations, however severe metabolic acidosis, hypoglycemia, and ketosis during the acute onset were consistent findings. Missense mutations in the ACAT1 gene are common genetic causes of β-ketothiolase deficiency.