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1.
Regulated cell death predominantly involves apoptosis, autophagy, and regulated necrosis. It is vital that we understand how key regulatory signals can control the process of cell death. Pin1 is a cis-trans isomerase that catalyzes the isomerization of phosphorylated serine or threonine-proline motifs of a protein, thereby acting as a crucial molecular switch and regulating the protein functionality and the signaling pathways involved. However, we know very little about how Pin1-associated pathw...  相似文献   
2.
After spinal cord injury(SCI),a fibroblast-and microglia-mediated fibrotic scar is formed in the lesion core,and a glial scar is formed around the fibrotic scar as a res ult of the activation and proliferation of astrocytes.Simultaneously,a large number of neuro ns are lost in the injured area.Regulating the dense glial scar and re plenishing neurons in the injured area are essential for SCI repair.Polypyrimidine tra ct binding protein(PTB),known as an RNA-binding protein,plays a key role in neu...  相似文献   
3.
Objective:The newly defined cancer-testis(CT)gene,MEIOB,was previously found to play key roles in DNA double-strand break(DSB)repair.In this study,we aimed to investigate the effects and mechanisms of MEIOB in the carcinogenesis of triple-negative breast cancers(TNBCs).Methods:The Cancer Genome Atlas database was used to quantify the expression of MEIOB.Cox regression analysis was used to evaluate the association between MEIOB expression and the prognosis of human TNBC.The effects of MEIOB on cell proliferation and migration in TNBCs were also assessed in vitro.Patient-derived xenograft(PDX)models were used to assess the sensitivity of breast cancers with active MEIOB to PARP1 inhibitors.Results:We confirmed MEIOB as a CT gene whose expression was restricted to the testes and breast tumors,especially TNBCs.Its activation was significantly associated with poor survival in breast cancer patients[overall,hazard ratio(HR)=1.90(1.16–2.06);TNBCs:HR=7.05(1.16–41.80)].In addition,we found that MEIOB was oncogenic and significantly promoted the proliferation of TNBC cells.Further analysis showed that MEIOB participated in DSB repair in TNBCs.However,in contrast to its function in meiosis,it mediated homologous recombination deficiency(HRD)through the activation of poly ADP-ribose polymerase(PARP)1 by interacting with YBX1.Furthermore,activated MEIOB was shown to confer sensitivity to PARP inhibitors,which was confirmed in PDX models.Conclusions:MEIOB played an oncogenic role in TNBC through its involvement in HRD.In addition,dysregulation of MEIOB sensitized TNBC cells to PARP inhibitors,so MEIOB may be a therapeutic target of PARP1 inhibitors in TNBC.  相似文献   
4.
Objective: Emerging studies have demonstrated the promising clinical value of circulating tumor cells(CTCs)for diagnosis, disease assessment, treatment monitoring and prognosis in epithelial ovarian cancer. However, the clinical application of CTC remains restricted due to diverse detection techniques with variable sensitivity and specificity and a lack of common standards.Methods: We enrolled 160 patients with epithelial ovarian cancer as the experimental group, and 90 patients including 50 pat...  相似文献   
5.
Huajuhong(Exocarpium Citri grandis,ECG)is a traditional Chinese herbal medicine and has been used for the treatment of respiratory diseases for hundreds of years.Recently,ECG has been listed in a traditional Chinese medicine formula in the Guidelines for the Diagnosis and Treatment of Coronavirus Disease 2019(sixth edition)in China.To date,the effect and mechanism of ECG against respiratory diseases have not been systematically reviewed.In this paper,the researchers summarized the effects of ECG and its pharmacologically active compound naringin in functioning as an antitussive and expectorant,improving lung function,alleviating acute lung injury,attenuating pulmonary fibrosis,and enhancing antiviral immune response,so as to provide a reference for its clinical application in the prevention and treatment of multiple respiratory diseases,including coronavirus disease 2019.  相似文献   
6.
Abnormal accumulation ofα-synuclein contributes to the formation of Lewy bodies in the substantia nigra,which is considered the typical pathological hallmark of Parkinson's disease.Recent research indicates that angiotensin-(1-7)plays a crucial role in several neurodegenerative disorders,including Parkinson's disease,but the underlying mechanisms remain elusive.In this study,we used intraperitoneal administration of rotenone to male Sprague-Dawley rats for 4 weeks to establish a Parkinson's disease model.We investigated whether angiotensin-(1-7)is neuroprotective in this model by continuous administration of angiotensin-(1-7)into the right substantia nigra for 4 weeks.We found that angiotensin-(1-7)infusion relieved characteristic parkinsonian behaviors and reducedα-synuclein aggregation in the substantia nigra.Primary dopaminergic neurons were extracted from newborn Sprague-Dawley rat substantia nigras and treated with rotenone,angiotensin-(1-7),and/or the Mas receptor blocker A-779 for 24 hours.After binding to the Mas receptor,angiotensin-(1-7)attenuated apoptosis andα-synuclein aggregation in rotenone-treated cells.Primary dopaminergic neurons were also treated with angiotensin-(1-7)and/or the autophagy inhibitor 3-methyladenine for 24 hours.Angiotensin-(1-7)increasedα-synuclein removal and increased the autophagy of rotenone-treated cells.We conclude that angiotensin-(1-7)reducesα-synuclein aggregation by alleviating autophagy dysfunction in Parkinson's disease.Therefore,the angiotensin-(1-7)/Mas receptor axis plays an important role in the pathogenesis of Parkinson's disease and angiotensin-(1-7)has potential therapeutic value for Parkinson's disease.All experiments were approved by the Biological Research Ethics Committee of Nanjing First Hospital(approval No.DWSY-2000932)in January 2020.  相似文献   
7.
Kaempferol is a natural flavonol that possesses various pharmacological activities,including anti-arthritis effects,yet the underlying mechanisms remain controversial.To evaluate the anti-arthritis efficacy and the underlying mechanisms of kaempferol,collagen-induced arthritis(CIA)mice were treated with kaempferol intragastrically(200 mg·kg^−1·d^−1)and intraperitoneally(20 mg·kg^−1·d^−1).Pharmacodynamic and pharmacokinetic studies showed that the oral administration of kaempferol produced distinct anti-arthritis effects in model mice with arthritis in terms of the spleen index,arthritis index,paw thickness,and inflammatory factors;the bioavailability(1.5%,relative to that of the intraperitoneal injection)and circulatory exposure of kaempferol(Cmax=0.23±0.06 ng/mL)and its primary metabolite kaempferol-3-O-glucuronide(Cmax=233.29±89.64 ng/mL)were rather low.In contrast,the intraperitoneal injection of kaempferol caused marginal anti-arthritis effects,although it achieved a much higher in vivo exposure.The much higher kaempferol content in the gut implicated a potential mechanism involved in the gut.Analysis of 16S ribosomal RNA revealed that CIA caused imbalance of 14 types of bacteria at the family level,whereas kaempferol largely rebalanced the intestinal microbiota in CIA mice.A metabolomics study showed that kaempferol treatment significantly reversed the perturbation of metabolites involved in energy production and the tryptophan,fatty acid and secondary bile acid metabolisms in the gut contents of the CIA mice.In conclusion,we demonstrate for the first time that the high level of kaempferol in the gut regulates the intestinal flora and microbiotic metabolism,which are potentially responsible for the anti-arthritis activities of kaempferol.  相似文献   
8.
After spinal cord injury,microglia as the first responders to the lesion display both beneficial and detrimental characteristics.Activated microglia phagocyte and eliminate cell debris,release cytokines to recruit peripheral immune cells to the injury site.Excessively activated microglia can aggravate the secondary damage by producing extravagant reactive oxygen species and pro-inflammatory cytokines.Recent studies demonstrated that the voltage-gated proton channel Hv1 is selectively expressed in microglia and regulates microglial activation upon injury.In mouse models of spinal cord injury,Hv1 deficiency ameliorates microglia activation,resulting in alleviated production of reactive oxygen species and pro-inflammatory cytokines.The reduced secondary damage subsequently decreases neuronal loss and correlates with improved locomotor recovery.This review provides a brief historical perspective of advances in investigating voltage-gated proton channel Hv1 and home in on microglial Hv1.We discuss recent studies on the roles of Hv1 activation in pathophysiological activities of microglia,such as production of NOX-dependent reactive oxygen species,microglia polarization,and tissue acidosis,particularly in the context of spinal cord injury.Further,we highlight the rationale for targeting Hv1 for the treatment of spinal cord injury and related disorders.  相似文献   
9.
Rheumatoid arthritis patients can be prescribed a combination of immunosuppressive drug leflunomide(LEF)and the antiviral drug acyclovir to reduce the high risk of infection.Acyclovir is a substrate of organic anion transporter(OAT)1/3 and multidrug resistance-associated protein(MRP)2.Considering the extraordinarily long half-life of LEF’s active metabolite teriflunomide(TER)and the kidney injury risk of acyclovir,it is necessary to elucidate the potential impact of LEF on the disposition of acyclovir.Here we used a specific MRP inhibitor MK571 and probenecid(OAT1/3 and MRP2 inhibitor)to assess the effects of MRP2 and OAT1/3 on the pharmacokinetics and tissue distribution of acyclovir in rats.We showed that LEF and probenecid,but not MK571 significantly increased the plasma concentration of acyclovir.However,kidney and liver exposures of acyclovir were increased when coadministered with LEF,probenecid or MK571.The kidney/plasma ratio of acyclovir was increased to approximately 2-fold by LEF or probenecid,whereas it was increased to as much as 14.5-fold by MK571.Consistently,these drugs markedly decreased the urinary excretion of acyclovir.TER(0.5−100μmol/L)dose-dependently increased the accumulation of acyclovir in MRP2-MDCK cells with an IC50 value of 4.91μmol/L.TER(5μmol/L)significantly inhibited the uptake of acyclovir in hOAT1/3-HEK293 cells.These results suggest that LEF/TER increased the kidney accumulation of acyclovir by inhibiting the efflux transporter MRP2,which increased its kidney/plasma ratio and renal injury risk.However,the inhibitory effects of LEF/TER on OAT1/3 reduced the tubular cells’uptake of acyclovir and increased the plasma concentration.  相似文献   
10.
The objective of this study was to provide research clues for the prevention and treatment of coronavirus disease?2019 (COVID?19) and coronavirus (CoV) infection using Traditional Chinese Medicine (TCM). A review on research and clinical trials that using TCM extracts and active ingredients against CoV was performed, and a table of TCM agents and their effects on CoV were summarized. Relevant analysis was performed and visual expression of the data included summarizing the types of TCM and treatment methods for COVID?19. TCM fighting against CoV is mainly used in the lung and heart channels, and its medicinal properties are mainly cold and mild, while its taste is mainly bitter and sweet. The majority of research focused on treatments that clear away heat and toxic materials and those that strengthen body resistance and tonify deficiencies. TCM has unique advantages to fight against CoV. The development of new anti?CoV therapy using TCM is of great significance for the prevention and treatment of COVID?19 pneumonia and various viral infectious diseases.  相似文献   
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