Effects of chronic Cr and Ni co-exposure on liver inflammation and autophagy in mice by regulating the TLR4/mTOR pathway.

Exposure to Cr and/or Ni can have widespread implications on the environment and health. However, the specific toxic effects of chronic Cr and Ni co-exposure on mice liver have not been reported. To ascertain the combined toxic effects of chronic Cr and Ni co-exposure on liver damage in mice, 80 6-week-old female C57BL/6 J mice were randomly divided into 4 groups: the Con group, Cr group (Cr+6 50 mg/L), Ni group (Ni+2 110 mg/L), and Cr + Ni group (Cr+6 50 mg/L + Ni+2 110 mg/L). The trial period lasted for 16 weeks. The results showed that Cr+6 and/or Ni+2 increased liver weight and liver index (P < 0.05) in mice, caused histological abnormality and ultrastructural damage, and micronutrients imbalance in mice liver. These findings serve as the basis for subsequent experiments. Compared with the individual exposure group, chronic Cr and Ni co-exposure resulted in decreased levels and activities of ALT, AST, MDA, T-AOC, and T-SOD (P < 0.05) in liver tissue, and decreased the mRNA expression levels of the TLR4/mTOR pathway related factors (TLR4, TRAM, TRIF, TBK-1, IRF-3, MyD88, IRAK-4, TRAF6, TAK-1, IKKß, NF-κB, IL-1ß, IL-6, TNFα, ULK1, Beclin 1, LC3) (P < 0.05) and decreased the protein expression levels of the factors (TLR4, MyD88, TRAF6, NF-κB p50, IL-6, TNFα, ULK1, LC3II/LC3I) (P < 0.05). Moreover, factorial analysis revealed the interaction between Cr and Ni, which was manifested as antagonistic effects on Cr concentration, Ni concentration, and TLR4, MyD88, NF-κB, mTOR, LC3, and p62 mRNA expression levels. In conclusion, the TLR4/mTOR pathway as a mechanism through which chronic Cr and Ni co-exposure induce liver inflammation and autophagy in mice, and there was an antagonistic effect between Cr and Ni. The above results provided a theoretical basis for understanding the underlying processes.

Relationship between semen parameters, serum InhB, and INSL-3 levels, and the degree of varicocele.

BACKGROUND: Varicocele is an abnormal expansion of the pampininias venous plexus in the scrotum, resulting in impaired sperm production and reduced sperm quality. The exact pathophysiological mechanism leading to varicocele-related infertility has not been fully elucidated. Although treatable, varicocele may lead to male infertility. OBJECTIVE: To investigate the relationship between semen parameters, serum InhB and INSL-3 levels, and the degree of varicocele in male patients. METHODS: Serum InhB and INSL-3 were detected. To evaluate the relationship between semen parameters and serum InhB and INSL-3 levels. To evaluate the value of semen parameters and serum InhB and INSL-3 levels in distinguishing disease severity in patients with varicocele. RESULTS: Serum INSL-3 in patients with varicocele decreased with the severity of the disease. Serum INSL-3 was positively correlated with total sperm count and frequency of normal sperm morphology. There was a weak correlation between serum InhB and semen volume, concentration, and total sperm. Patients with different disease severity were similar within the groups, with partial overlap or similarity between varicocele Grade I and Grade II, and significant differences between Grade III and Grade I and II. Semen volume, concentration, total sperm, normal sperm morphology, and serum InhB and INSL-3 levels could distinguish the degree of varicocele. CONCLUSION: Semen parameters and the combination of serum InhB and INSL-3 levels in patients with varicocele are closely related to the severity of the disease. Serum INSL-3 is expected to be a potential biomarker for early clinical intervention.

Relationship between semen parameters, serum InhB, and INSL-3 levels, and the degree of varicocele

Abstract Background Varicocele is an abnormal expansion of the pampininias venous plexus in the scrotum, resulting in impaired sperm production and reduced sperm quality. The exact pathophysiological mechanism leading to varicocele-related infertility has not been fully elucidated. Although treatable, varicocele may lead to male infertility. Objective To investigate the relationship between semen parameters, serum InhB and INSL-3 levels, and the degree of varicocele in male patients. Methods Serum InhB and INSL-3 were detected. To evaluate the relationship between semen parameters and serum InhB and INSL-3 levels. To evaluate the value of semen parameters and serum InhB and INSL-3 levels in distinguishing disease severity in patients with varicocele. Results Serum INSL-3 in patients with varicocele decreased with the severity of the disease. Serum INSL-3 was positively correlated with total sperm count and frequency of normal sperm morphology. There was a weak correlation between serum InhB and semen volume, concentration, and total sperm. Patients with different disease severity were similar within the groups, with partial overlap or similarity between varicocele Grade I and Grade II, and significant differences between Grade III and Grade I and II. Semen volume, concentration, total sperm, normal sperm morphology, and serum InhB and INSL-3 levels could distinguish the degree of varicocele. Conclusion Semen parameters and the combination of serum InhB and INSL-3 levels in patients with varicocele are closely related to the severity of the disease. Serum INSL-3 is expected to be a potential biomarker for early clinical intervention.

Butyrate alleviates renal fibrosis in CKD by regulating NLRP3-mediated pyroptosis via the STING/NF-κB/p65 pathway.

Chronic kidney disease (CKD) is a serious and irreversible disease primarily characterized by chronic inflammation and renal fibrosis. Recent studies have suggested that gut microbiota-related metabolites, particularly short-chain fatty acids (SCFAs) are significantly associated with kidney diseases. Notably, butyrate, a type of SCFAs, plays a crucial role in this correlation. However, the effect of butyrate on renal fibrosis in patients with CKD and its potential mechanisms remain unclear. In this study, we demonstrated that butyrate levels are reduced as CKD progresses using a CKD C57BL/6 mouse model established by a 0.2% adenine diet. Exogenous supplementation of butyrate effectively alleviated renal fibrosis and repressed the levels of proteins associated with NLRP3-mediated pyroptosis (NLRP3, IL-1ß, caspase-1, and GSDMD). Additionally, we conducted an in vitro experiment using HK-2 cells, which also confirmed that the elevated levels of NLRP3-mediated pyroptosis proteins in TGF-ß1-stimulated HK-2 cells are reversed by butyrate intervention. Further, butyrate mitigated the activity of the STING/NF-κB/p65 pathway, and STING overexpression impaired the protective function of butyrate in CKD. Hence, we suggest that butyrate may have a renoprotective role in CKD, alleviating renal fibrosis possibly by regulating NLRP3-mediated pyroptosis via the STING/NF-κB/p65 pathway.

Inhibition of semaphorin-3a suppresses lipopolysaccharide-induced acute kidney injury.

Semaphorin-3a (Sema3A), a soluble axon guidance cue, appears to play an important role in the development of acute kidney injury (AKI) and has been regarded as an early diagnostic marker to evaluate the progression of AKI. However, the role of Sema3A in sepsis-associated AKI remains unknown. In this study, lipopolysaccharide (LPS) was used to simulate sepsis-associated AKI and the role of Sema3A in LPS-induced AKI was investigated in vivo and in vitro. In our in vivo study, Sema3A was found in tubular epithelial cells (TECs), which presented a higher level after LPS treatment. Meanwhile, the results of our in vitro experiment showed that Sema3A was also elevated in NRK-52E cells treated by LPS. Notably, inhibition of Sema3A by (-)-epigallocatechin-3-gallate (EGCG) could significantly reduce kidney inflammation and apoptosis in mice. Likewise, EGCG intervention also ameliorated the inflammation and apoptosis of cells in vitro. Furthermore, our research also found that the Rac1/NF-κB p65 and JNK pathways were possibly involved in the Sema3A-mediated inflammation and apoptosis of TECs, respectively. Our findings suggest that Sema3A play a pathogenic role by promoting inflammation and apoptosis of TECs in LPS-induced AKI. It might serve as a useful treatment target in ameliorating sepsis-associated AKI. KEY MESSAGES: Sema3A is upregulated in LPS-induced AKI. Inhibition of Sema3A attenuates inflammation and apoptosis of TECs in LPS-induced AKI. Sema3A enhances the LPS-induced inflammation of TECs through the Rac1/NF-κB p65 pathway. Sema3A exacerbates the LPS-induced apoptosis of TECs through the JNK pathway.

Attenuation of everolimus-induced cytotoxicity by a protective autophagic pathway involving ERK activation in renal cell carcinoma cells.

AIM: The mammalian target of rapamycin (mTOR) pathway is a critical target for cancer treatment and the mTOR inhibitor everolimus (RAD001) has been approved for treatment of renal cell carcinoma (RCC). However, the limited efficacy of RAD001 has led to the development of drug resistance. Autophagy is closely related to cell survival and death, which may be activated under RAD001 stimulation. The aim of the present study was to identify the underlying mechanisms of RAD001 resistance in RCC cells through cytoprotective autophagy involving activation of the extracellular signal-regulated kinase (ERK) pathway. METHODS AND RESULTS: RAD001 strongly induced autophagy of RCC cells in a dose- and time-dependent manner, as confirmed by Western blot analysis. Importantly, suppression of autophagy by the pharmacological inhibitor chloroquine effectively enhanced RAD001-induced apoptotic cytotoxicity, as demonstrated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Western blot analysis, indicating a cytoprotective role for RAD001-induced autophagy. In addition, as was shown by the MTT assay, flow cytometry, and Western blot analysis, RAD001 robustly activated ERK, but not c-Jun N-terminal kinase and p38. Activation of ERK was inhibited by the pharmacological inhibitor selumetinib (AZD6244), which effectively promoted RAD001-induced cell death. Moreover, employing AZD6244 markedly attenuated RAD001-induced autophagy and enhanced RAD001-induced apoptosis, which play a central role in RAD001-induced cell death. Furthermore, RAD001-induced autophagy is regulated by ERK-mediated phosphorylation of Beclin-1 and B-cell lymphoma 2, as confirmed by Western blot analysis. CONCLUSION: These results suggest that RAD001-induced autophagy involves activation of the ERK, which may impair cytotoxicity of RAD001 in RCC cells. Thus, inhibition of the activation of ERK pathway-mediated autophagy may be useful to overcome chemoresistance to RAD001.

Hypoxia-induced autophagy promotes gemcitabine resistance in human bladder cancer cells through hypoxia-inducible factor 1α activation.

Overcoming the chemoresistance of bladder cancer is a pivotal obstacle in clinical treatments. Hypoxia widely exists in solid tumors and has been demonstrated to contribute to chemoresistance through hypoxia-inducible factor 1α (HIF­1α)-mediated autophagy in several types of cancer. However, it is unclear whether HIF­1α-mediated autophagy and chemoresistance occur in bladder cancer. The present study demonstrated that HIF­1α was overexpressed in 20 bladder cancer tissues compared with matched paracarcinoma tissues. Gemcitabine-induced apoptosis during hypoxia was significantly reduced compared with that observed under normoxic conditions. In addition, hypoxia activated autophagy and enhanced gemcitabine-induced autophagy. Combined treatment using gemcitabine and an autophagy inhibitor (3-methyladenine) under hypoxia significantly increased gemcitabine cytotoxicity. Furthermore, it was demonstrated that hypoxia-activated autophagy depended on the HIF­1α/BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 (BNIP3)/Beclin1 signaling pathway. Suppressing HIF­1α inhibited autophagy, BNIP3 and Beclin1, as well as enhanced gemcitabine-induced apoptosis in bladder cancer cells under hypoxic conditions. Consequently, the results of the present study demonstrated that hypoxia-induced cytoprotective autophagy counteracted gemcitabine-induced apoptosis through increasing HIF­1α expression. Therefore, targeting HIF­1α-associated pathways or autophagy in bladder cancer may be a successful strategy to enhance the sensitivity of bladder cancer chemotherapy.

Inhibiting autophagy overcomes docetaxel resistance in castration-resistant prostate cancer cells.

BACKGROUND: This study investigates the docetaxel-resistant mechanism and explores the effect of tea polyphenols (TP) on autophagy and its related mechanism in human castration-resistant prostate cancer (CRPC) cell lines PC3 and DU145. METHODS: Immunofluorescence assay and annexin V-FITC/PI double staining flow cytometry were used to analyze the apoptosis and autophagy of PC3 and DU145 cells. The expression of autophagy-related proteins was detected by western bolt. RESULTS: Docetaxel could induce autophagy and apoptosis, together with the expression increase in p-JNK, p-Bcl-2 and Beclin1. The level of autophagy was remarkably decreased, but apoptosis was increased after combining with TP. In addition, the expression of p-mTOR was increased after combining with TP. CONCLUSION: Docetaxel induces protective autophagy in CRPC cells by JNK pathway activation and then Bcl-2 phosphorylation and Beclin1 dissociation. TP activates mTOR pathway, which ultimately inhibits docetaxel-induced autophagy and improves therapeutic efficacy of docetaxel in CRPC cells.