Parkinson’s disease (PD) is a neurodegenerative disorder characterized by the progressive loss of dopamine (DA) neurons in the substantia nigra pars compacta (SNpc), primarily manifesting as motor dysfunctions such as resting tremor, muscle rigidity, and bradykinesia. According to the classical model of basal ganglia motor control, approximately half of the medium spiny neurons (MSNs) in the striatum are D1-MSNs, which constitute the direct pathway. These neurons express D₁-dopamine receptor (D₁R) and substance P, and they mainly participate in the selection, initiation, and execution of movements. The other half are D2-MSNs, which constitute the indirect pathway. These neurons express D₂-dopamine receptor (D₂R) and adenosine 2A receptors and are involved in inhibiting unnecessary movements or terminating ongoing movements, thereby adjusting movement sequences to perform more precise motor behaviors. The direct pathway in the striatum modulates the activity of motor cortex neurons by exciting D1-MSNs through neurotransmitters such as glutamate (Glu), allowing the motor cortex to send signals more freely to the motor system, thus facilitating the generation and execution of specific motor behaviors. Studies using D1-Cre and D2-Cre mice with neurons labeled for D₁R and D₂R have shown that both types of neurons are involved in the execution of movements, with D1-MSNs participating in movement initiation and D2-MSNs in inhibiting actions unrelated to the target movement. These findings suggest that the structural and functional plasticity of D1-MSNs and D2-MSNs in the basal ganglia circuitry enables motor learning and behavioral regulation. Additionally, when SNpc DA neurons begin to degenerate, D1-MSNs are initially affected but do not immediately cause motor impairments. In contrast, when D2-MSNs undergo pathological changes, they are first activated by upstream projecting neurons, leading to the inhibition of most motor behaviors and resulting in motor dysfunction. Therefore, it is hypothesized that motor impairments such as bradykinesia and initiation difficulties are more closely related to the functional activity of D2-MSNs. The extracellular signal-regulated kinase (Erk)/mitogen-activated protein kinase (MAPK) signaling pathway has been identified as a critical modulator in the pathophysiology of PD. Recent findings indicate that Erk/MAPK signaling pathway can mediate DA and Glu signaling in the central nervous system, maintaining normal functional activity of striatal MSNs and influencing the transmission of motor control signals. Within this complex regulatory network, the Erk/MAPK signaling pathway plays a key role in transmitting motor information to downstream neurons, regulating normal movements, avoiding unnecessary movements, and finely tuning motor behaviors. Our laboratory’s previous research found that 4 weeks of aerobic exercise intervention improved motor dysfunction in PD mice by inhibiting the Erk1/2 signaling upstream of striatal MSNs, primarily involving the Erk1/2 signaling in D2-MSNs rather than D1-MSNs. This review summarizes the neurobiological mechanisms of Erk/MAPK signaling pathway in D2-MSNs for the prevention and treatment of motor dysfunction in PD. By exploring the role of this signaling pathway in regulating motor abnormalities and preventing motor dysfunction in the central nervous system of PD, this review provides new theoretical perspectives for related mechanistic research and therapeutic strategies.

The development of bone in human body and the maintenance of bone mass in adulthood are regulated by a variety of biological factors. Myocyte enhancer factor 2C (MEF2C), as one of the many factors regulating bone tissue development and balance, has been shown to play a key role in bone development and metabolism. However, there is limited systematic analysis on the effects of MEF2C on bone tissue. This article reviews the role of MEF2C in bone development and metabolism. During bone development, MEF2C promotes the development of neural crest cells (NC) into craniofacial cartilage and directly promotes cartilage hypertrophy. In terms of bone metabolism, MEF2C exhibits a differentiated regulatory model across different types of osteocytes, demonstrating both promoting and other potential regulatory effects on bone formation, with its stimulating effect on osteoclasts being determined. In view of the complex roles of MEF2C in bone tissue, this paper also discusses its effects on some bone diseases, providing valuable insights for the physiological study of bone tissue and strategies for the prevention of bone diseases.
Humans ; MEF2 Transcription Factors/physiology* ; Bone and Bones/metabolism* ; Animals ; Bone Development/physiology* ; Osteogenesis/physiology* ; Myogenic Regulatory Factors/physiology*

OBJECTIVES: To evaluate preterm white matter injury (PWMI) in neonatal rats using multimodal magnetic resonance imaging (MRI) combined with histological assessments and to explore its underlying mechanisms. METHODS: Healthy 3-day-old Sprague-Dawley neonatal rats were randomly divided into a sham operation group and a PWMI group (n=12 in each group). A PWMI model was established in neonatal rats through hypoxia-ischemia. Laser speckle imaging was used to observe changes in cerebral oxygen saturation and blood flow at different time points post-modeling. Multimodal MRI was employed to assess the condition of white matter injury, while hematoxylin-eosin staining was utilized to observe morphological changes in the striatal area on the injured side. Immunofluorescence staining was performed to detect the proliferation and differentiation of oligodendrocyte precursor cells. RESULTS: At 0, 6, 12, 24, and 72 hours post-modeling, the relative blood flow and relative oxygen saturation on the injured side in the PWMI group were significantly lower than those in the sham operation group (P<0.05). At 24 hours post-modeling, T2-weighted imaging showed high signals in the white matter of the injured side in the PWMI group, with relative apparent diffusion coefficient values and Lorenz differential values being lower than those in the sham operation group (P<0.001); additionally, the arrangement of nerve cells in the PWMI group was disordered, and the number of EdU⁺PDGFR-α⁺ cells was higher than that in the sham operation group (P<0.001). At 28 days post-modeling, the relative fractional anisotropy values, the number of EdU⁺Olig2⁺ cells, and the fluorescence intensity of myelin basic protein and neurofilament protein 200 in the white matter region of the PWMI group were all lower than those in the sham operation group (P<0.001). CONCLUSIONS Multimodal MRI can evaluate early and long-term changes in PWMI in neonatal rat models in vivo, providing both imaging and pathological evidence for the diagnosis and treatment of PWMI in neonates. Hypoxia-ischemia inhibits the proliferation and differentiation of oligodendrocyte precursor cells in neonatal rats, leading to PWMI.
Animals ; Rats, Sprague-Dawley ; Magnetic Resonance Imaging/methods* ; Rats ; White Matter/injuries* ; Animals, Newborn ; Female ; Multimodal Imaging ; Male ; Hypoxia-Ischemia, Brain/pathology*

OBJECTIVE: To analyze the efficacy and safety of decitabine-based myeloablative preconditioning regimen for allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with acute myeloid leukemia (AML). METHODS: The clinical characteristics and efficacy of 115 AML patients who underwent allo-HSCT at the First Medical Center of Chinese PLA General Hospital from August 2018 to August 2022 were retrospectively analyzed, including 37 patients treated with decitabine conditioning regimen (decitabine group) and 78 patients without decitabine conditioning regimen (non-decitabine group). The cumulative incidence of relapse (CIR), overall survival (OS), leukemia-free survival (LFS), non-relapse mortality (NRM) and graft versus host disease (GVHD) were analyzed. RESULTS: For the patients in first complete remission (CR1) state before allo-HSCT, the 1-year relapse rates of decitabine group(22 cases) and non-decitabine group(69 cases) were 9.1% and 29.6%, respectively, the difference was statistically significant(P =0.042). The 1-year cumulative incidence of acute graft-versus-host disease (aGVHD) in decitabine group and non-decitabine group was 62.2% and 70.5%, respectively, and the 1-year cumulative incidence of chronic inhibitor-versus-host disease (cGVHD) was 18.9% and 14.1%, respectively, there were no significant differences in the incidence of aGVHD and cGVHD between the two groups (P >0.05). Of the 115 patients, there were no significantly differences in the 1-year CIR(21.7% vs 28.8%, P =0.866), NRM(10.9% vs 3.9%, P =0.203), OS(75.2% vs 83.8%, P =0.131) and LFS(74.6% vs 69.1%, P =0.912) between the decitabine group(37 cases) and the non-decitabine group(78 cases). CONCLUSION Decitabine-based conditioning regimen could reduce the relapse rate of AML CR1 patients with good safety.
Humans ; Leukemia, Myeloid, Acute/therapy* ; Hematopoietic Stem Cell Transplantation/methods* ; Decitabine/therapeutic use* ; Transplantation Conditioning/methods* ; Retrospective Studies ; Graft vs Host Disease ; Transplantation, Homologous ; Male ; Female ; Adult ; Middle Aged ; Adolescent ; Young Adult

OBJECTIVE: To explore the efficacy and adverse reactions of CAG regimen combined with venetoclax, chidamide, and azacitidine in the treatment of elderly patients with acute myeloid leukemia (AML). METHODS: 15 elderly AML patients aged≥60 years old who were admitted to the Hematology Department of our hospital from May 2022 to October 2023 were treated with the CAG regimen combined with venetoclax, chidamide and azacitidine, and the efficacy, treatment-related adverse events, overall survival (OS) and event-free survival (EFS) were analyzed. RESULTS: After one course of treatment, 11 out of 15 patients achieved complete response (CR), 3 patients achieved CR with incomplete hematologic recovery (CRi), and 1 patient died due to prior infection before efficacy evaluation, and the overall response rate (ORR) was 93.3% (14/15). The median follow-up time was 131 (19-275) days, with median OS and EFS both remaining unreached. Next-generation sequencing (NGS) analysis showed that among the 15 patients, 13 were detected with gene mutations, and there were 7 genes with mutation frequencies of more than 10%, including ASXL1 (4 cases), RUNX1 (4 cases), BCOR (3 cases), DNMT3A (3 cases), STAG2 (2 cases), IDH1/2 (2 cases), and TET (2 cases). Among the 13 patients with detectable mutations, 12 patients achieved composite response (CR+CRi). The average recovery time of white blood cell count was 14.6 days after chemotherapy, and the average recovery time of platelets was 7.7 days after chemotherapy. The main adverse event was myelosuppression, with 10 patients accompanied by infection. Except for 1 patient who died due to septic shock during chemotherapy, no patients experienced serious complications such as heart, liver, or kidney damage during the treatment process. CONCLUSION The CACAG+V regimen, which combines the CAG regimen with venetoclax, chidamide, and azacitidine, can be applied in the treatment of elderly AML patients, demonstrating good safety and induction remission rate.
Humans ; Leukemia, Myeloid, Acute/drug therapy* ; Bridged Bicyclo Compounds, Heterocyclic/therapeutic use* ; Sulfonamides/therapeutic use* ; Aminopyridines/therapeutic use* ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use* ; Azacitidine/therapeutic use* ; Aged ; Benzamides/therapeutic use* ; Male ; Female ; Treatment Outcome ; Middle Aged ; Cytarabine ; Aclarubicin ; Granulocyte Colony-Stimulating Factor

Idiopathic pulmonary fibrosis (IPF), a chronic interstitial lung disease, is characterized by aberrant wound healing, excessive scarring and the formation of myofibroblastic foci. Although the role of alternative splicing (AS) in the pathogenesis of organ fibrosis has garnered increasing attention, its specific contribution to pulmonary fibrosis remains incompletely understood. In this study, we identified an up-regulation of serine/arginine-rich splicing factor 7 (SRSF7) in lung fibroblasts derived from IPF patients and a bleomycin (BLM)-induced mouse model, and further characterized its functional role in both human fetal lung fibroblasts and mice. We demonstrated that enhanced expression of Srsf7 in mice spontaneously induced alveolar collagen accumulation. Mechanistically, we investigated alternative splicing events and revealed that SRSF7 modulates the alternative splicing of pyruvate kinase (PKM), leading to metabolic dysregulation and fibroblast activation. In vivo studies showed that fibroblast-specific knockout of Srsf7 in conditional knockout mice conferred resistance to bleomycin-induced pulmonary fibrosis. Importantly, through drug screening, we identified lomitapide as a novel modulator of SRSF7, which effectively mitigated experimental pulmonary fibrosis. Collectively, our findings elucidate a molecular pathway by which SRSF7 drives fibroblast metabolic dysregulation and propose a potential therapeutic strategy for pulmonary fibrosis.

Objective:To investigate the efficacy of cytoreductive radical prostatectomy (CRP) in patients with oligometastatic prostate cancer, and to assess its impact on progression-free survival (PFS), overall survival (OS), as well as the incidence and severity of complications.Methods:A prospective, monocentric non-randomized controlled trial including 80 cases of oligometastatic prostate cancer admitted to the Second Affiliated Hospital of Air Force Military Medical University from January 2020 to June 2024 was conducted. There were 40 patients each assigned to CRP group and no local treatment (NLT) group. The study used multivariate analysis to account for potential biases, analyzed the effects of CRP on PFS, OS as well as circulating tumor cell (CTC) and DNA methylation status. Meanwhile, the incidence and severity of complications were recorded. Measurement data were expressed as mean ± standard deviation ( ± s), and t-test was used for inter-group comparison. Count data and rank data were expressed as number of cases and percentage, and Chi-test was used for comparison between groups. Kaplan-Meier method was used to calculate PFS and OS, and Log-rank test was used to compare differences between groups. Multivariate analysis was performed using Cox proportional hazard regression model. A time-dependent Cox regression model was used to consider the effect of follow-up time on the results. Results:The PFS and OS in the CRP group were significantly better than those in the NLT group. The PFS rates in CRP group and NLT group at 12 months were 60% and 35% ( P=0.030). The OS rates at 12 months in the CRP group reached 80%, compared to 50% in the NLT group ( P=0.040). The level of CTC in the CRP group decreased from 50 cells/mL at first month to 5 cells/mL at 12th month, and the DNA methylation status decreased from 0.75 at first month to 0.30 at 12th month, which were significantly better than those in the NLT group ( P<0.05). The incidence of complications decreased gradually from first month to 12th month, with the CRP group from 30% to 10%, and the NLT group from 25% to 12% ( P=0.080). Although the severity of complications was slightly higher in the CRP group than in the NLT group at the early stage, the difference in severity gradually narrowed and eventually became similar between the two groups by the 12th month of follow-up. Conclusion:CRP significantly prolonged PFS and OS in patients with oligometastatic prostate cancer, reduced tumor burden, and despite a higher incidence of early complications, overall safety was good.

Osteosarcopenia (OS) is a multifactorial, multiaetiologic degenerative metabolic syndrome in which sarcopenia coexists with osteoporosis, and its influences are related to aging-induced mechanics, genetics, inflammatory factors, endocrine disorders, and irregular lifestyles. With the accelerated aging process in our country, osteosarcopenia has become a public health problem that cannot be ignored, with a higher risk of falls, fractures, impaired mobility and death. In recent years, scholars at home and abroad have conducted a lot of research on osteosarcopenia, but their pathogenesis is still unclear. Understanding the signaling pathways associated with osteosarcopenia is of great significance for further research on the pathogenesis of these disorders and for finding new targets for treatment. Studies have shown that activation of the PI3K/Akt signaling pathway promotes osteoblast differentiation as well as skeletal muscle regeneration, indicating that inhibition of thePI3K/Akt signaling pathway is closely related to the development of osteosarcopenia. Muscle factor-mechanical stress interactions can maintain osteoblast viability by activating the Wnt/β-catenin signaling pathway, suggesting that Wnt signaling is important in muscle and bone crosstalk. The Notch signaling pathway also plays an important role in improving bone and muscle mass and function, but different researchers hold different views, which need to be further validated and refined in subsequent studies. Exercise, as an existing non-pharmacological treatment with strong and sustained effects on physical function and muscle strength, also significantly increases bone density in osteoporosis patients, which may be mainly due to the fact that exercise induces changes in the form and function of bones, in the form of muscular pulling and indirectly improves the bone mass, and changes in the bone strength can also change the number, shape as well as the function of the muscles. At the same time, the mechanism of different exercise modalities focuses on different aspects, and there are differences in exercise time, exercise intensity, and therapeutic effects in the implementation of interventions. Aerobic exercise can improve the quality of skeletal muscle and increase the expression of osteogenesis-related genes by stimulating mitochondrial biosynthesis, as well as improve the quality and strength of bones and muscles through the Wnt/β- catenin and PI3K/Akt signaling pathways, effectively preventing and controlling the occurrence of musculoskeletal disorders. High-intensity resistance exercise has a significant effect on improving the quality of muscles and bone mineral density, but older people with osteosarcopenia suffer from a decline in muscle quality and strength, and a decline in bone mineral density, which makes them very susceptible to fracture, so they should select the intensity of the training in a gradual and orderly manner, from small to large. What kind of exercise intensity and exercise modalities are most effective in improving the occurrence and development of osteosarcopenia needs to be further investigated. Therefore, this paper mainly reviews the epidemiology of osteosarcopenia, diagnostic criteria, the related signaling pathways (PI3K/Akt pathway, Wnt/β-catenin pathway, Notch pathway, NF-κB pathway) that jointly regulate the metabolic process of myocytes and skeletal cells, as well as the interventional effects of different exercise modes on osteosarcopenia, with the aim of providing theoretical bases for the clinical treatment of osteosarcopenia, as well as enhancing the preventive capacity of the disease in old age.

Osteoporosis leads to an imbalance in bone remodelling, where bone resorption is greater than bone formation and osteoclast degradation increases, resulting in severe bone loss. Autophagy is a lysosomal degradation pathway that regulates the proliferation, differentiation, and apoptosis of various bone cells (including osteoblasts, osteoclasts, and osteoclasts), and is deeply involved in the bone remodelling process. In recent years, the role of autophagy in the progression of osteoporosis and related bone metabolic diseases has received more and more attention, and it has become a research hotspot in this field. Summarising the existing studies, it is found that senile osteoporosis is the result of a combination of factors. On the one hand, it is the imbalance of bone remodelling and the increase of bone resorption/bone formation ratio with ageing, which causes progressive bone loss. On the other hand, aging leads to a general decrease in the level of autophagy, a decrease in the activity of osteoblasts and osteoclasts, and an inhibition of osteogenic differentiation. The lack of oestrogen leads to the immune system being in a low activation state, and the antioxidant capacity is weakened and inflammatory response is increased, inducing autophagy-related proteins to participate in the transmission of inflammatory signals, excessive accumulation of reactive oxygen species (ROS) in the skeleton, and negatively regulating bone formation. In addition, with aging and the occurrence of related diseases, glucocorticoid treatments also mediate autophagy in bone tissue cells, contributing to the decline in bone strength. Exercise, as an effective means of combating osteoporosis, improves bone biomechanical properties and increases bone density. It has been found that exercise induces oxidative stress, energy imbalance, protein defolding and increased intracellular calcium ions in the organism, which in turn activates autophagy. In bone, exercise of different intensities activates messengers such as ROS, PI3K, and AMP. These messengers signal downstream cascades, which in turn induce autophagy to restore dynamic homeostasis in vivo. During exercise, increased production of AMP, PI3K, and ROS activate their downstream effectors, AMPK, Akt, and p38MAPK, respectively, and these molecules in turn lead to activation of the autophagy pathway. Activation of AMPK inhibits mTOR activity and phosphorylates ULK1 at different sites, inducing autophagy. AMPK and p38 up-regulate per-PGC-1α activity and activate transcription factors in the nucleus, resulting in increased autophagy and lysosomal genes. Together, they activate FoxOs, whose transcriptional activity controls cellular processes including autophagy and can act on autophagy key proteins, while FoxOs proteins are expressed in osteoblasts. Exercise also regulates the expression of mTORC1, FoxO1, and PGC-1 through the PI3K/Akt signalling pathway, which ultimately plays a role in the differentiation and proliferation of osteoblasts and regulates bone metabolism. In addition, BMPs signaling pathway and long chain non-coding RNAs also play a role in the proliferation and differentiation of osteoblasts and autophagy process under exercise stimulation. Therefore, exercise may become a new molecular regulatory mechanism to improve osteoporosis through the bone autophagy pathway, but the specific mechanism needs to be further investigated. How exercise affects bone autophagy and thus prevents and treats bone-related diseases will become a future research hotspot in the fields of biology, sports medicine and sports science, and it is believed that future studies will further reveal its mechanism and provide new theoretical basis and ideas.

Cyclin-dependent kinases (CDKs) are proline-induced serine/threonine kinases that are primarily involved in the regulation of cell cycle, gene transcription, and cell differentiation. In general, CDKs are activated by binding to specific regulatory subunits of cell cycle proteins and are regulated by phosphorylation of specific T-loops by CDK activated kinases. In the CDKs family, cyclin-dependent kinase 5 (CDK5) is a specialized member whose activity is triggered only by interaction with p35 and p39, which do not have the same sequence as the cell cycle proteins, and this may be one reason why CDK5 is distinguished from other CDK members by its structural and functional differences. In addition, unlike most CDK members that require phosphorylation at specific sites to function, CDK5 does not require such phosphorylation, and it can be activated simply by binding to p35 and p39. More notably, inhibitors that are commonly used to inhibit the activity of other CDK members have almost zero effect on CDK5. In contrast, CDK5, as a unique CDK family member, plays an important role in the development of numerous diseases. In metabolic diseases, elevated CDK5 expression leads to decreased insulin secretion, increased foam cell formation and triggers decreased bone mass in the body, thus accelerating metabolic diseases, and the role of CDK5 in bone biology is gradually gaining attention, and the role of CDK5 in bone metabolic diseases may become a hotspot for research in the future; in neurodegenerative diseases, hyperphosphorylation of Tau protein is an important hallmark of Alzheimer’s disease development, and changes in CDK5 expression are associated with Tau protein phosphorylation and nerve death, indicating that CDK5 is highly related to the development of the nervous system; in tumor diseases, the role of CDK5 in the proliferation, differentiation and migration and invasion of tumor cells marks the development of tumorigenesis, but different researchers hold different views, and further studies are needed in the follow-up. Therefore, the study of its mechanism of action in diseases can help to reveal the pathogenesis and pathological process of diseases. Appropriate exercise not only helps in the prevention of diseases, but also plays a positive role in the treatment of diseases. Exercise-induced mechanical stress can improve bone microstructure and increase bone mass in osteoporosis patients. In addition, exercise can effectively inhibit neuronal apoptosis and improve mitochondrial dysfunction, more importantly, appropriate exercise can inhibit the proliferation of cancer cells to a certain extent. It can be seen that exercise occupies a pivotal position in the prevention and treatment of pathologic diseases. It has been shown that exercise can reduce the expression of CDK5 and affect the pathological process of neurological diseases. Currently, there is a dearth of research on the specific mechanisms of CDK5’s role in improving disease outcomes through exercise. In order to understand its effects more comprehensively, subsequent studies need to employ diverse exercise modalities, targeting patients with various types of diseases or corresponding animal models for in-depth exploration. This article focuses on the pathological functions of CDK5 and its relationship with exercise, with a view to providing new insights into the prevention and treatment of disease by CDK5.