Loss of protein homeostasis is a hallmark of cellular senescence, and ribosome pausing plays a crucial role in the collapse of proteostasis. However, our understanding of ribosome pausing in senescent cells remains limited. In this study, we utilized ribosome profiling and G-quadruplex RNA immunoprecipitation sequencing techniques to explore the impact of RNA G-quadruplex (rG4) on the translation efficiency in senescent cells. Our results revealed a reduction in the translation efficiency of rG4-rich genes in senescent cells and demonstrated that rG4 structures within coding sequence can impede translation both in vivo and in vitro. Moreover, we observed a significant increase in the abundance of rG4 structures in senescent cells, and the stabilization of the rG4 structures further exacerbated cellular senescence. Mechanistically, the RNA helicase DHX9 functions as a key regulator of rG4 abundance, and its reduced expression in senescent cells contributing to increased ribosome pausing. Additionally, we also observed an increased abundance of rG4, an imbalance in protein homeostasis, and reduced DHX9 expression in aged mice. In summary, our findings reveal a novel biological role for rG4 and DHX9 in the regulation of translation and proteostasis, which may have implications for delaying cellular senescence and the aging process.
G-Quadruplexes ; Cellular Senescence ; Ribosomes/genetics* ; Humans ; Animals ; Mice ; DEAD-box RNA Helicases/genetics* ; Protein Biosynthesis ; RNA/chemistry* ; Neoplasm Proteins

Objective To investigate the role of dynamin-related protein 1(Drp-1)and peroxisome proliferator-activated receptor γ coactivator 1-α(PGC-1α)in the lung tissues of neonatal rats with meconium aspiration syndrome(MAS)and its mechanism.Methods Fifty 2-3-week-old SD neonatal rats were randomly divided into five groups(n=10):control group,model group and SN50 low,medium and high concentration groups.In control group,2 ml/kg of saline was injected into the trachea after tracheal exposure,and 2 ml/kg of meconium suspension was injected into the trachea of the rest of groups;after 24 h,control and model groups were left untreated,and 100 μl of each of SN50 concentrations of 10,30,and 60 μg/ml was injected into SN50 low,medium,and high concentration groups intraperitoneally;the rats of each group were killed after 6 h,and the chest X-rays,the gross views of the lungs,the lung wet/dry weight ratios(W/D),and the lungs of the rats in control group and model group were examined.After 6 h,the rats in each group were executed,and the pathological changes of lung tissue were observed by chest radiographs,lung gross view,lung wet/dry weight ratio(W/D)and HE staining;Western blotting was used to detect the changes of nuclear factor κB(NF-κB)(p65),p-NF-κB p65(p-p65),Drp-1,and PGC-1α proteins expression in neonatal rat lung tissues,and immuno-histochemistry was used to observe the expression of p65,Drp-1,and PGC-1α related proteins expression in neonatal rat lung tissues.Results Compared with control group,model group showed inflammatory infiltration in the chest radiograph and gross view,and the W/D and lung injury pathology scores were significantly higher(P＜0.05);compared with model group,the chest radiograph and gross view of inflammation were slightly reduced in SN50 low,medium and high concentration groups,and the W/D and lung injury pathology scores were significantly lower(P＜0.05).Western blotting showed that,compared with control group,the protein expression levels of p-p65 and Drp-1 in the lung tissues of neonatal rats were significantly higher in model group(P＜0.05),and the protein expression level of PGC-1α was significantly lower(P＜0.05);compared with model group,the protein expression levels of p-p65 and Drp-1 were significantly lower in SN50 low,medium,and high concentration groups(P＜0.05),and the difference in the protein expression level of PGC-1α in SN50 low concentration group was not statistically significant(P＞0.05),whereas the PGC-1α expression levels in SN50 medium and high concentration groups were significantly higher(P＜0.05);the difference in the total p65 protein expression levels in each group was not statistically significant(P＞0.05).Immunohistochemical assay results showed that,compared with control group,p65 and Drp-1 protein expression levels were significantly higher in model group(P＜0.05),and PGC-1α protein expression level was significantly lower(P＜0.05);compared with model group,p65 protein expression level was significantly lower in SN50 low concentration group(P＜0.05),and the difference in Drp-1 and PGC-1α protein expression levels were not statistically significant(P＞0.05),Drp-1 protein expression level was significantly lower(P＜0.05),and PGC-1α protein expression level was significantly higher(P＜0.05)in SN50 middle and high concentration groups.Conclusion Fecal inhalation can induce lung tissue inflammation in neonatal rats,and the mechanism may be related to enhanced oxidative stress,promotion of mitochondrial dysfunction,activation of the Drp-1/NF-κB signaling pathway,and inhibition of PGC-1α protein expression.

Although significant progress has been made in the development of novel targeted drugs for the treatment of acute myeloid leukemia(AML)in recent years,chemotherapy still remains the mainstay of treatment and the overall survival is poor in most patients.Here,we demonstrated the antileukemia activity of a novel small molecular compound NL101,which is formed through the modification on bendamustine with a suberanilohydroxamic acid(SAHA)radical.NL101 suppresses the proliferation of myeloid malignancy cells and primary AML cells.It induces DNA damage and caspase 3-mediated apoptosis.A genome-wide clustered regularly interspaced short palindromic repeats(CRISPR)library screen revealed that phosphatase and tensin homologous(PTEN)gene is critical for the regulation of cell survival upon NL101 treatment.The knockout or inhibition of PTEN significantly reduced NL101-induced apoptosis in AML and myelodysplastic syndrome(MDS)cells,accompanied by the activation of protein kinase B(AKT)signaling pathway.The inhibition of mammalian target of rapamycin(mTOR)by rapamycin enhanced the sensitivity of AML cells to NL101-induced cell death.These findings uncover PTEN protein expression as a major determinant of chemosensitivity to NL101 and provide a novel strategy to treat AML with the combination of NL101 and rapamycin.

Objective:To investigate the causal correlation between depression and stress urinary incontinence(SUI)using Mendelian randomization(MR)analysis.Methods:We searched the FinnGen Consortium database for genome-wide association studies(GWAS)on depression and obtained 23 424 case samples and 192 220 control samples,with the GWAS data on SUI provided by the UK Biobank,including 4 340 case samples and 458 670 control samples.We investigated the correlation between depression and SUI based on the depression data collected from the Psychiatric Genomics Consortium(PGC).We employed inverse-variance weighting as the main method for the MR study,and performed sensitivity analysis to verify the accuracy and stability of the findings.Results:Analysis of the data from the UK Biobank and FinnGen Consortium showed that depression was significantly correlated with an increased risk of SUI(P=0.005),but not SUI with the risk of depression(P=0.927).And analysis of the PGC data verified the correlation of depression with the increased risk of SUI(P=0.043).Conclusion:Depression is associated with an increased risk of SUI,while SUI does not increase the risk of depression.

Objective:To retrospectively analyze the clinical and pathologic characteristics, response to treatment, survival, and prognosis of patients with primary large B-cell lymphoma of the central nervous system (PCNSLBCL) .Methods:Clinical and pathologic data of 70 patients with PCNSLBCL admitted to Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from December 2010 to November 2022 were collected for retrospective analysis. Survival analysis was performed using the Kaplan-Meier method and log-rank test, and prognosis analysis was conducted using the Cox proportional hazards model.Results:Among 70 patients with PCNSLBCL, complete remission (CRs) were achieved in 49 (70.0% ) and partial remission in 4 (5.7% ) after the first-line induction therapy; the overall remission rate was 75.7%. The 2-year progression-free survival (PFS) rate was 55.8% and the median progression-free survival (mPFS) time was 35.9 months, whereas the 2-year overall survival (OS) rate was 79.1% with a median OS time not reached. After CR induced by first-line therapy, cumulative incidence of relapse (CIR) was lower in patients who had received auto-HSCT than in those who had not received consolidation therapy ( P=0.032), whose 2-year PFS rate was 54.4% and mPFS time was 35.9 months; comparatively, the 2-year PFS rate in patients having received oral maintenance of small molecule drugs reached 84.4% with a mPFS time of 79.5 months ( P=0.038). Multivariant analysis demonstrated that Class 3 in the Memorial Sloan-Kettering Cancer Center (MSKCC) prognostic model is an independent adverse prognostic factor of OS in patients with PCNSLBCL ( HR=3.127, 95% CI 1.057-9.253, P=0.039) . Conclusions:In patients with PCNSLBCL achieving CR after the first-line induction therapy, auto-HSCT as consolidation therapy would lead to a decreased CIR, and PFS time could be prolonged by oral maintenance of small molecule drugs. Class 3 MSKCC prognostic model is independently associated with poorer OS.

Transcatheter aortic valve replacement(TAVR)is the use of interventional catheter to transport the artificial heart valve to the aortic valve area through the patient's arterial,venous system or left ventricular apex,then release it to replace the original aortic valve to achieve normal physiological function.The"suicide left ventricle"phenomenon refers to the paradoxical hemodynamic collapse of dynamic left ventricular obstruction caused by left ventricular hypertrophy and hypersystole after the removal of the fixed valve obstruction of aortic stenosis after TAVR.The clinical manifestation is abnormal continuous hypotension that is ineffective to positive inotropic drugs during the operation or within a few hours after the operation.With the indications for transcatheter aortic valve surgery covering patients with low,medium and high risk of severe aortic stenosis,surgery-related complications have been reported to increase gradually."Suicide left ventricle"is worth studying and exploring as a fatal potential complication.This article mainly reviews four aspects of the overview of"suicide left ventricle",pathological mechanism,risk-related indicators,prevention strategies and treatment methods to be highly vigilant and make corresponding emergency plans for patients with aortic stenosis who may have suicide left ventricle risk,so as to minimize perioperative mortality.

The interaction between organelles is the focus of re-search in neural development.The contact site of endoplasmic reticulum and mitochondria is the focus of Parkinson's disease(PD)in recent years.The research shows that mitochondria,endoplasmic reticulum(ER),lysosome and other organelles play an important role in neurogenesis.Specifically,metabolic turnover,reactive oxygen species production,mitochondrial dy-namics,mitochondrial autophagy,mitochondria-mediated apop-tosis,and interactions between mitochondria and the ER all play a role in neurogenesis.In PD,abnormal ER-mitochondrial inter-action can affect mitochondrial calcium overload,mitochondrial fission and fusion imbalance,and lipid homeostasis disorder.Therefore,here we review the recent progress in the main regu-latory mechanisms of ER-mitochondrial interaction and address the effects of abnormal ER-mitochondrial interactions on PD.

Aim To investigate the effects of multi-gly-cosides of Tripterygium wilfordii(GTW)on mitochon-drial dynamics-related proteins and the mechanism of nephroprotective effects in IgA nephrophathy(IgAN)rats.Methods SPF grade male SD rats were random-ly divided into the Control group,modelling group,prednisone group(6.25 mg·kg·d-1)and GTW group(6.25 mg·kg·d-1).The IgAN rat model was established by the method of"bovine serum albumin(BSA)+carbon tetrachloride(CCl4)+lipopolysac-charide(LPS)".The total amount of urinary protein(24 h-UTP)and erythrocyte count in urine were meas-ured in 24 h urine.Blood biochemistry of serum albu-min(ALB),alanine aminotransferase(ALT),urea ni-trogen(BUN),and creatinine(Scr)were measured in abdominal aorta of the rats;immunofluorescence and HE staining were used to observe the histopathology of the kidneys;RT-PCR and Western blotting were used to detect the mRNA and protein expression levels of key proteins regulating mitochondrial division and fu-sion:dynamin-related protein 1(Drp1),mitochondrial fusion protein 1(Mfn1),and mitochondrial fusion pro-tein 2(Mfn2),and PTEN-induced putative kinase 1(Pink1),in the kidney tissue of rats.Results GTW significantly reduced urinary erythrocyte count and 24 h-UTP,decreased serum ALT,BUN and Scr levels,in-creased serum ALB levels,improved renal histopatho-logical status in IgAN rats,increased the protein and mRNA expression levels of Mfn1,Mfn2,and Pink1,and decreased the protein and mRNA expression levels of Drp1 in renal tissues.Conclusions GTW may regu-late mitochondrial structure and maintain the dynamic balance of mitochondrial dynamics by promoting the ex-pression of Mfn1,Mfn2,Pink1 and decreasing Drp1.This may result in a reduction in urinary erythrocyte counts and proteinuria,and an improvement in renal function.

Aim To explore the mechanism of action of Tripterygium glycosides tablets on kidney of rats with IgA nephropathy based on inflammation-related path-ways.Methods Forty-five male SD rats of SPF grade were randomly divided into control group and modeling group.In addition to the blank group,the modeling group used the combination of bovine serum albumin(BSA)+carbon tetrachloride(CC14)+lipopolysac-charide(LPS)to establish the IgA nephropathy rat model.Successfully modeled rats were randomly divid-ed into the model group,the prednisone group and Tripterygium glycosides tablets group,and the treat-ment group was given the drug by gavage from the 13 th week,and the 24 hours urine,blood and kidney tis-sues of the rats were collected and examined after 4 weeks of the administration of the drug.Urine erythro-cyte count,quantitative 24-h urine protein(24 h-UTP),urea nitrogen(BUN),and blood creatinine(Scr)were detected in each group;serum interleukin 1β(IL-1β)and tumor necrosis factor α(TNF-α)were detected by enzyme-linked immunosorbent assay(Elisa);the pathological changes in the renal tissues of the rats in each group were observed by horizontal hematoxylin-eosin(HE)staining;and the renal tis-sues in each group were observed by Western blotting.The expressions of LIGHT,HVEM,LTβR proteins and their mRNAs in rat kidney tissue were detected by Western blot and real-time fluorescence quantitative polymerase chain reaction(RT-PCR).Results Tripterygium glycosides tablets significantly reduced the levels of urinary erythrocyte count,24 h-UTP,BUN,and Scr in IgA nephropathy rats(P＜0.01),improved renal histopathology,lowered the levels of se-rum inflammatory factors IL-1β and TNF-α(P＜0.01),and lowered the levels of LIGHT,HVEM,LTβR proteins and their mRNA expression in renal tis-sues(P＜0.01).Conclusions Tripterygium glyco-sides tablets may inhibit the immune response and re-duce the release of inflammatory factors by down-regu-lating the LIGHT-HVEM/LT(3R pathway,thus reduc-ing the inflammatory response,lowering the urinary e-rythrocytes and urinary proteins,improving the renal nephron pathologic injury,and protecting the renal function.

Aim To investigate the effects of berberine(BBR)combined with 5'-n-ethylformamidoadenosine(NECA)on myocardial H9c2 and HL-1 cell damage induced by hypoxia/reoxygenation(H/R).Methods H9c2 and HL-1 cells were divided into the Control group,BBR group,NECA group,combined administra-tion group,H/R group,BBR+H/R group,NECA+H/R group,and combined administration+H/R group.CCK-8 was used to detect cell viability in each group.The TMRE kit was used to detect MMP.DCFH-DA was used to detect ROS content.The Mito SOX Red fluorescent probe was used to detect mitochondrial su-peroxide.The expressions of COX Ⅳ,Tom20,and Tim23 were detected by Western blot.The expression of COX Ⅳ and Tom20 genes was detected by qRT-PCR.Results In H9c2 cells,the cell viability and TMRE fluorescence intensity in the H/R group were significantly decreased compared with the Control group.The protein expressions of COX Ⅳ,Tom20,and Tim23,gene expressions of COX Ⅳ and Tom20,ROS,and mitochondrial superoxide contents were significant-ly increased.Compared with the H/R group,the cell viability of BBR and NECA were enhanced after ad-ministration alone.The contents of ROS and mitochon-drial superoxide were significantly decreased.In HL-1 cells,cell viability in the H/R group was significantly decreased compared with the Control group.The con-tents of ROS and mitochondrial superoxide were signifi-cantly increased.Compared with the H/R group,BBR and NECA alone and combined administration en-hanced cell viability.The contents of ROS and mito-chondrial superoxide were significantly decreased.Conclusion The administration of BBR and NECA a-lone or in combination can reduce the production of mi-tochondrial superoxide and cell ROS,thereby allevia-ting mitochondrial damage,alleviating oxidative stress damage,and ultimately reducing H/R-induced myocar-dial cell damage.