Human umbilical cord mesenchymal stem cells attenuate diabetic nephropathy through the IGF1R-CHK2-p53 signalling axis in male rats with type 2 diabetes mellitus. / 人脐带间å 质干细胞通过IGF1R-CHK2-p53信号轴减轻2åž‹ç³–å°¿ç— é›„æ€§å¤§é¼ ç³–å°¿ç— è‚¾ç— .

Diabetes mellitus (DM) is a disease syndrome characterized by chronic hyperglycaemia. A long-term high-glucose environment leads to reactive oxygen species (ROS) production and nuclear DNA damage. Human umbilical cord mesenchymal stem cell (HUcMSC) infusion induces significant antidiabetic effects in type 2 diabetes mellitus (T2DM) rats. Insulin-like growth factor 1 (IGF1) receptor (IGF1R) is important in promoting glucose metabolism in diabetes; however, the mechanism by which HUcMSC can treat diabetes through IGF1R and DNA damage repair remains unclear. In this study, a DM rat model was induced with high-fat diet feeding and streptozotocin (STZ) administration and rats were infused four times with HUcMSC. Blood glucose, interleukin-6 (IL-6), IL-10, glomerular basement membrane, and renal function were examined. Proteins that interacted with IGF1R were determined through coimmunoprecipitation assays. The expression of IGF1R, phosphorylated checkpoint kinase 2 (p-CHK2), and phosphorylated protein 53 (p-p53) was examined using immunohistochemistry (IHC) and western blot analysis. Enzyme-linked immunosorbent assay (ELISA) was used to determine the serum levels of 8-hydroxydeoxyguanosine (8-OHdG). Flow cytometry experiments were used to detect the surface markers of HUcMSC. The identification of the morphology and phenotype of HUcMSC was performed by way of oil red "O" staining and Alizarin red staining. DM rats exhibited abnormal blood glucose and IL-6/10 levels and renal function changes in the glomerular basement membrane, increased the expression of IGF1 and IGF1R. IGF1R interacted with CHK2, and the expression of p-CHK2 was significantly decreased in IGF1R-knockdown cells. When cisplatin was used to induce DNA damage, the expression of p-CHK2 was higher than that in the IGF1R-knockdown group without cisplatin treatment. HUcMSC infusion ameliorated abnormalities and preserved kidney structure and function in DM rats. The expression of IGF1, IGF1R, p-CHK2, and p-p53, and the level of 8-OHdG in the DM group increased significantly compared with those in the control group, and decreased after HUcMSC treatment. Our results suggested that IGF1R could interact with CHK2 and mediate DNA damage. HUcMSC infusion protected against kidney injury in DM rats. The underlying mechanisms may include HUcMSC-mediated enhancement of diabetes treatment via the IGF1R-CHK2-p53 signalling pathway.

Human umbilical cord mesenchymal stem cells attenuate diabetic nephropathy through the IGF1R-CHK2-p53 signalling axis in male rats with type 2 diabetes mellitus. / 人脐带间å 质干细胞通过IGF1R-CHK2-p53信号轴减轻2åž‹ç³–å°¿ç— é›„æ€§å¤§é¼ ç³–å°¿ç— è‚¾ç— .

Diabetes mellitus (DM) is a disease syndrome characterized by chronic hyperglycaemia. A long-term high-glucose environment leads to reactive oxygen species (ROS) production and nuclear DNA damage. Human umbilical cord mesenchymal stem cell (HUcMSC) infusion induces significant antidiabetic effects in type 2 diabetes mellitus (T2DM) rats. Insulin-like growth factor 1 (IGF1) receptor (IGF1R) is important in promoting glucose metabolism in diabetes; however, the mechanism by which HUcMSC can treat diabetes through IGF1R and DNA damage repair remains unclear. In this study, a DM rat model was induced with high-fat diet feeding and streptozotocin (STZ) administration and rats were infused four times with HUcMSC. Blood glucose, interleukin-6 (IL-6), IL-10, glomerular basement membrane, and renal function were examined. Proteins that interacted with IGF1R were determined through coimmunoprecipitation assays. The expression of IGF1R, phosphorylated checkpoint kinase 2 (p-CHK2), and phosphorylated protein 53 (p-p53) was examined using immunohistochemistry (IHC) and western blot analysis. Enzyme-linked immunosorbent assay (ELISA) was used to determine the serum levels of 8-hydroxydeoxyguanosine (8-OHdG). Flow cytometry experiments were used to detect the surface markers of HUcMSC. The identification of the morphology and phenotype of HUcMSC was performed by way of oil red "O" staining and Alizarin red staining. DM rats exhibited abnormal blood glucose and IL-6/10 levels and renal function changes in the glomerular basement membrane, increased the expression of IGF1 and IGF1R. IGF1R interacted with CHK2, and the expression of p-CHK2 was significantly decreased in IGF1R-knockdown cells. When cisplatin was used to induce DNA damage, the expression of p-CHK2 was higher than that in the IGF1R-knockdown group without cisplatin treatment. HUcMSC infusion ameliorated abnormalities and preserved kidney structure and function in DM rats. The expression of IGF1, IGF1R, p-CHK2, and p-p53, and the level of 8-OHdG in the DM group increased significantly compared with those in the control group, and decreased after HUcMSC treatment. Our results suggested that IGF1R could interact with CHK2 and mediate DNA damage. HUcMSC infusion protected against kidney injury in DM rats. The underlying mechanisms may include HUcMSC-mediated enhancement of diabetes treatment via the IGF1R-CHK2-p53 signalling pathway.

USP25 Elevates SHLD2-Mediated DNA Double-Strand Break Repair and Regulates Chemoresponse in Cancer.

DNA damage plays a significant role in the tumorigenesis and progression of the disease. Abnormal DNA repair affects the therapy and prognosis of cancer. In this study, it is demonstrated that the deubiquitinase USP25 promotes non-homologous end joining (NHEJ), which in turn contributes to chemoresistance in cancer. It is shown that USP25 deubiquitinates SHLD2 at the K64 site, which enhances its binding with REV7 and promotes NHEJ. Furthermore, USP25 deficiency impairs NHEJ-mediated DNA repair and reduces class switch recombination (CSR) in USP25-deficient mice. USP25 is overexpressed in a subset of colon cancers. Depletion of USP25 sensitizes colon cancer cells to IR, 5-Fu, and cisplatin. TRIM25 is also identified, an E3 ligase, as the enzyme responsible for degrading USP25. Downregulation of TRIM25 leads to an increase in USP25 levels, which in turn induces chemoresistance in colon cancer cells. Finally, a peptide that disrupts the USP25-SHLD2 interaction is successfully identified, impairing NHEJ and increasing sensitivity to chemotherapy in PDX model. Overall, these findings reveal USP25 as a critical effector of SHLD2 in regulating the NHEJ repair pathway and suggest its potential as a therapeutic target for cancer therapy.

Peer Victimization and Adolescent Mental Health: School-level Victimization as a Moderator.

As a global issue, peer victimization is closely associated with adolescent mental health. Although previous research has explored the relationship between peer victimization and mental health in some contexts, the school context, particularly within the Chinese cultural context, has not received sufficient attention. Based on the Healthy Context Paradox, this study aimed to explore the moderating role of school-level victimization in the relationship between individual-level peer victimization and mental health. This study tested two hypotheses by using a multilevel design: higher individual-level and school-level peer victimization are associated with higher depressive symptoms and lower life satisfaction (Hypothesis 1); school-level victimization moderates the association between individual-level peer victimization and mental health (Hypothesis 2). Participants were 39,720 adolescents (50.41% females; Mage = 13.68, SD = 2.39) across 292 Chinese schools. They completed a set of questionnaires, including the Center for Epidemiologic Studies Depression Scale, the single-item Life Satisfaction Questionnaire, the Peer Victimization Scale, and demographics. The multilevel model indicated that both individual-level and school-level peer victimization were positively correlated with depressive symptoms and negatively correlated with life satisfaction. In schools with lower levels of victimization, there was a stronger association between individual peer victimization and adolescent mental health. A potential explanation for these results might be the victimization visibility and perceived severity in different contexts. These findings extended the discussion of the Healthy Context Paradox within the Chinese school context and provided valuable insights for developing school support strategies for victimized adolescents. School management might play a significant role in affecting the mental health of victimized adolescents.

Germline Mutations of Holliday Junction Resolvase Genes in Multiple Primary Malignancies Involving Lung Cancer Lead to PARP Inhibitor Sensitization.

PURPOSE: The incidence of multiple primary malignancies (MPM) involving lung cancer has increased in recent decades. There is an urgent need to clarify the genetic profile of such patients and explore more efficacious therapy for them. EXPERIMENTAL DESIGN: Peripheral blood samples from MPM involving patients with lung cancer were assessed by whole-exome sequencing (WES), and the identified variants were referenced for pathogenicity using the public available database. Pathway enrichment analysis of mutated genes was performed to identify the most relevant pathway. Next, the effects of mutations in relevant pathway on function and response to targeted drugs were verified by in vitro and in vivo experiments. RESULTS: Germline exomes of 71 patients diagnosed with MPM involving lung cancer were sequenced. Pathway enrichment analysis shows that the homologous recombination repair (HRR) pathway has the strongest correlation. Moreover, HRR genes, especially key Holliday junction resolvases (HJR) genes (GEN1, BLM, SXL4, and RMI1), were most frequently mutated, unlike the status in the samples from patients with lung cancer only. Next, we identified a total of seven mutations in HJR genes led to homologous recombination DNA repair deficiency and rendered lung cancer cells sensitive to PARP inhibitor treatment, both in vitro and in vivo. CONCLUSIONS: This is the first study to map the profile of germline mutations in patients with MPM involving lung cancer. This study may shed light on early prevention and novel targeted therapies for MPM involving patients with lung cancer with HJR mutations.

NADPH oxidase 4-mediating oxidative stress contributes to endometriosis.

NADPH oxidase 4 (NOX4) plays an important role in the regulation of oxidative stress, which is associated with endometriosis. This study aims to investigate the effects of NOX4 in endometriosis and its molecular mechanisms. Clinical specimens were collected, and human endometrial stromal cells (HESCs) were isolated. The knockdown of NOX4 cell lines was established on the HESCs and induced by peritoneal fluid. The levels of NOX4 were determined by using immunohistochemistry (IHC) staining, western blotting, and qPCR, respectively. The levels of oxidative stress markers were determined by using western blotting and ELISAs, respectively. The correlation of NOX4 and oxidative stress markers was analyzed by the Pearson correlation coefficient. The levels of NOX4 were dramatically elevated in the ectopic endometrium. Besides, oxidative stress biomarkers were also dysregulated in the ectopic endometrium as compared to the normal endometrium. Pearson's correlation coefficient analysis revealed a relationship between NOX4 and oxidative stress biomarkers in the ectopic endometrium. NOX4 modulated the expressions of oxidative stress markers in endometrial stromal cells stimulated by the peritoneal fluid from endometriosis. The effects of NOX4 on endometriosis are in part by its regulatory effects against oxidative stress.

Clinical Diagnostic Values of C1q/TNF-Related Protein-3 for Polycystic Ovary Syndrome Women with Insulin Resistance.

Polycystic ovary syndrome (PCOS) is the most common disease caused by complex endocrine and metabolic abnormalities in women. Insulin resistance is considered an important pathophysiological factor in the pathogenesis of PCOS. Here we investigated the clinical values of C1q/TNF-related protein-3 (CTRP3) as predictive factor for insulin resistance. Our study included 200 patients with PCOS, among which 108 had insulin resistance. Serum CTRP3 levels were measured using enzyme-linked immunosorbent assay. Predictive values of CTRP3 for insulin resistance was analyzed using receiver operating characteristic (ROC) analysis. Correlations of CTRP3 to insulin levels, obesity measurements and blood lipid levels were determined using Spearman's correlation analysis. Our data suggested that PCOS patients with insulin resistance had a higher obesity, lower high-density lipoprotein cholesterol, higher total cholesterol, higher insulin levels and lower CTRP3 levels. CTRP3 had a high sensitivity (72.22%) and specificity (72.83%). CTRP3 significantly correlated to insulin levels, body mass index, waist-to-hip ratio, high-density lipoprotein, and total cholesterol levels. The predictive value of CTRP3 in PCOS patients with insulin resistance was supported by our data. Our findings suggest that CTRP3 is involved in the pathogenesis and insulin resistance of PCOS, which indicates its value as an indicator for the PCOS diagnosis.

DNA damage repair gene signature model for predicting prognosis and chemotherapy outcomes in lung squamous cell carcinoma.

BACKGROUND: Lung squamous cell carcinoma (LUSC) is prone to metastasis and likely to develop resistance to chemotherapeutic drugs. DNA repair has been reported to be involved in the progression and chemoresistance of LUSC. However, the relationship between LUSC patient prognosis and DNA damage repair genes is still unclear. METHODS: The clinical information of LUSC patients and tumour gene expression level data were downloaded from the TCGA database. Unsupervised clustering and Cox regression were performed to obtain molecular subtypes and prognosis-related significant genes based on a list including 150 DNA damage repair genes downloaded from the GSEA database. The coefficients determined by the multivariate Cox regression analysis and the expression level of prognosis-related DNA damage repair genes were employed to calculate the risk score, which divided LUSC patients into two groups: the high-risk group and the low-risk group. Immune viability, overall survival, and anticarcinogen sensitivity analyses of the two groups of LUSC patients were performed by Kaplan-Meier analysis with the log rank test, ssGSEA and the pRRophetic package in R software. A time-dependent ROC curve was applied to compare the survival prediction ability of the risk score, which was used to construct a survival prediction model by multivariate Cox regression. The prediction model was used to build a nomogram, the discriminative ability of which was confirmed by C-index assessment, and its calibration was validated by calibration curve analysis. Differentially expressed DNA damage repair genes in LUSC patient tissues were retrieved by the Wilcoxon test and validated by qRT-PCR and IHC. RESULT: LUSC patients were separated into two clusters based on molecular subtypes, of which Cluster 2 was associated with worse overall survival. A prognostic prediction model for LUSC patients was constructed and validated, and a risk score calculated based on the expression levels of ten DNA damage repair genes was employed. The clinical utility was evaluated by drug sensitivity and immune filtration analyses. Thirteen-one genes were upregulated in LUSC patient samples, and we selected the top four genes that were validated by RT-PCR and IHC. CONCLUSION: We established a novel prognostic model based on DNA damage repair gene expression that can be used to predict therapeutic efficacy in LUSC patients.

USP17L2-SIRT7 axis regulates DNA damage repair and chemoresistance in breast cancer cells.

PURPOSE: Sirtuin7 (SIRT7), as a member of the sirtuin and NAD+-dependent protein-modifying enzyme family, plays an important role in regulating cellular metabolism, stress responses, tumorigenesis, and aging. Ubiquitination and deubiquitination are reversible post-translational modifications that regulate protein stability, enzyme activity, protein-protein interactions, and cellular signaling transduction. However, whether SIRT7 is regulated by deubiquitination signaling is unclear. This study aims to elucidate the molecular mechanism of SIRT7 via deubiquitination signaling. METHODS: USP17L2 or SIRT7-targeting shRNAs were used to deplete USP17L2 or SIRT7. Western blot was applied to assess the effects of USP17L2 or SIRT7 depletion. A co-immunoprecipitation assay was used to detect the interaction relationship. Cell Counting Kit-8 assays were applied to assess the viability of breast cancer cells. An immunohistochemistry assay was employed to detect the protein level in samples from breast cancer patients, and the TCGA database was applied to analyze the survival rate of breast cancer patients. Statistical analyses were performed with the Student's t test (two-tailed unpaired) and χ2 test. RESULTS: We find that the deubiquitinase USP17L2 interacts with and deubiquitinates SIRT7, thereby increasing SIRT7 protein stability. In addition, USP17L2 regulates DNA damage repair through SIRT7. Furthermore, SIRT7 polyubiquitination is increased by knocking down of USP17L2, which leads to cancer cells sensitizing to chemotherapy. In breast cancer patient samples, high expression of USP17L2 is correlated with increased levels of SIRT7 protein. In conclusion, our study demonstrates that the USP17L2-SIRT7 axis is the new regulator in DNA damage response and chemo-response, suggesting that USP17L2 may be a prognostic factor and a potential therapeutic target in breast cancer. CONCLUSION: Our results highlighted that USP17L2 regulates the chemoresistance of breast cancer cells in a SIRT7-dependent manner. Moreover, the role of USP17L2 as a potential therapeutic target in breast cancer and a prognostic factor for patients was elucidated.

Efficiency moderates the relationship between sleep-onset insomnia and resting-state electroencephalogram microstate.

BACKGROUND: Overactivation of the salience network (SN) causes hyperarousal in insomnia patients and is associated with sleep-onset insomnia (SOI). Resting-state microstate 3 (RS-MS3) duration is closely related to SN overactivation. However, whether RS-MS3 duration is a biomarker for SOI has not yet been reported in the literature. In addition, SN activity is also associated with efficiency. However, it is not clear whether there are individual differences in the neural mechanisms of SOI in different efficiency groups. METHODS: Considering that RS-MS3 duration characterizes the stability and persistent activation of the SN in the resting state, the current study investigated the link between SOI measured by sleep latency of Pittsburg Sleep Quality Index (PSQI), efficiency measured by Kirton Adaption-Innovation Inventory (KAI), and RS-MS3 in a Chinese healthy (subclinical) student population, using electroencephalography (EEG) microstate analysis. RESULTS: We found that RS-MS3 duration was positively correlated with sleep latency and efficiency. The interaction between sleep latency and efficiency was significant. Simple slope analysis showed that high sleep latency was positively correlated with longer RS-MS3 duration in participants with higher efficiency scores. This correlation did not exist in participants with low efficiency scores. CONCLUSIONS: RS-MS3 duration may serve as a biomarker for SOI. There is heterogeneity in the relationship between SOI and RS-MS3 duration between individuals with high and low efficiency.

DUB3/KLF4 combats tumor growth and chemoresistance in hepatocellular carcinoma.

This study aimed to investigate the role of deubiquitinating enzyme 3 (DUB3) in the regulation of Krüppel-like factor 4 (KLF4) expression in hepatocellular carcinoma (HCC). Gain- and loss-of-function assay, luciferase reporter assay, co-immunoprecipitation, and intracellular and extracellular deubiquitination assays were conducted in vitro. A tumor xenograft mouse model was established. The expression of DUB3 and KLF4 was examined in HCC patient specimens. The results showed that DUB3 upregulated KLF4 expression by deubiquitinating and stabilizing KLF4 protein in HCC cells through binding with KLF4. DUB3 inhibited HCC cell proliferation in vitro and tumor growth in vivo while enhancing the chemosensitivity of HCC cells in a KLF4-dependent manner. Furthermore, KLF4 promoted DUB3 transcription by binding to the DUB3 promoter. In HCC patients, DUB3 expression positively correlated with KLF4 expression in HCC tissues. Low DUB3 expression predicted worse overall survival and recurrence in HCC patients. In conclusion, this study revealed a positive DUB3/KLF4 feedback loop that inhibits tumor growth and chemoresistance in HCC. These results suggest that DUB3/KLF4 activation might be a potential therapeutic approach for HCC treatment.

The Role of Alternative Splicing Factors, DDB2-Related Ageing and DNA Damage Repair in the Progression and Prognosis of Stomach Adenocarcinoma Patients.

DNA damage response is a key signal transduction pathway in triggering ageing and tumor progression. Abnormal alternative splicing (AS) is associated with tumors and ageing. However, the role of AS factors associated with DNA damage repair and ageing in stomach adenocarcinoma (STAD) remains unclear. We downloaded the percentage of splicing (PSI) values for AS in STAD from the TCGA SpliceSeq database. The PSI values of DNA repair gene AS events were integrated with STAD patient survival data for Cox regression analysis. The prediction model for the overall survival (OS) was constructed by the clinical traits. The tumor immune microenvironment was analyzed by CIBERSORT and ESTIMATE. We detected 824 AS events originating from 166 DNA repair genes. Cox regression analysis provided 21 prognostic AS events connected with OS statistically, and a prognostic prediction model was constructed. The expression of these AS factors was higher in STAD tumors. DDB2 high senescence levels were associated with active immune responses and better survival in STAD patients. We built a novel prognostic model founded on DNA repair genes with AS events and identified that DDB2 may be a potential biomarker to apply in clinics.

Relationship Between Trait Mindfulness and Sleep Quality in College Students: A Conditional Process Model.

Sleep quality can affect the physical and mental health, as well as the personal development of college students. Mindfulness practices are known to ameliorate sleep disorder and improve sleep quality. Trait mindfulness, an innate capacity often enhanced by mindfulness training, has been shown to relate to better sleep quality and different aspects of psychological well-being. However, how individual difference factors such as trait mindfulness relate to sleep quality remains largely unclear, which limits the optimization and further application of mindfulness-based intervention schemes targeting the improvement of sleep quality. In this study, we aimed to investigate how negative emotions and neuroticism may influence the relationship between trait mindfulness and sleep quality. A conditional process model was built to examine these relationships in 1,423 Chinese young adults. Specifically, the conditional process model was constructed with trait mindfulness as the independent variable, sleep quality as the dependent variable, negative emotions as the mediating variable, and neuroticism as the moderating variable. Our results showed that negative emotions mediated the link between mindfulness and sleep quality and that neuroticism had a moderating effect on the relationship between mindfulness and sleep quality. Together, these findings suggested a potential mechanism of how trait mindfulness influences sleep quality, provided a therapeutic target for which mindfulness-based interventions may act upon to improve sleep quality, and offered a basis for prediction of different intervention effects among individuals.