Pin1 aggravates renal injury induced by ischemia and reperfusion in rats via Nrf2/HO-1 mediated endoplasmic reticulum stress.

PURPOSE: To investigate the role of peptidyl-prolyl cis/trans isomerase 1 (Pin1) on renal ischemia-reperfusion (I/R) injury and underlying mechanism. METHODS: By establishing the in vitro and in vivo models of renal I/R, the role of Pin1 was explored by using molecular assays. RESULTS: In renal I/R, endogenous Pin1 level was up-regulated in I/R-impaired kidney. Suppression of Pin1 with juglone afforded protection against I/R-mediated kidney dysfunction, and reduced I/R-induced endoplasmic reticulum (ER) stress in vivo. Consistent with the in vivo results, repression of Pin1 with juglone or gene knockdown with si-Pin1 conferred cytoprotection and restricted hypoxia/reoxygenation (H/R)-driven ER stress in HK-2 cells. Simultaneously, further study uncovered that Nrf-2/HO-1 signals was the association between Pin1 and ER stress in response to renal I/R. In addition, Nrf-2/HO-1 signal pathway was inactivated after kidney exposed to I/R, as indicated by the down-regulation of Nrf-2/HO-1 levels. Furthermore, inhibition of Pin1 remarkably rescued the inactivation ofNrf-2/HO-1. CONCLUSIONS: Pin1 modulated I/R-mediated kidney injury in ER stress manner dependent on Nrf2-HO-1 pathway in I/R injury.

Fucoxanthin Attenuates Oxidative Damage by Activating the Sirt1/Nrf2/HO-1 Signaling Pathway to Protect the Kidney from Ischemia-Reperfusion Injury.

Oxidative stress is a key component of renal ischemia/reperfusion (I/R) injury. Fucoxanthin (Fx), a marine carotenoid with enhanced antioxidant capacity, acts as a ROS inhibitor in diseases such as ischemic stroke and acute lung injury. We hypothesized that fucoxanthin could attenuate renal I/R-induced oxidative damage. C57BL/6 mice (n = 30) were randomly assigned to sham, IR, IR + DMSO, and IR + Fx (25, 50, and 100 mg/kg) groups. The renal I/R injury was induced by clamping the left kidney nephron tip in mice. Fucoxanthin was injected intraperitoneally 24 hours before surgery. Compared with the IR group, pretreatment with fucoxanthin significantly improved renal dysfunction and tissue structural damage and inhibited ROS levels and apoptosis. Consistent results were observed in HK-2 cells. Besides, we found that renal I/R resulted in decreased expression of Sirt1, Nrf2, and HO-1, while fucoxanthin upregulated the expression of Sirt1, Nrf2, and HO-1. The protective effects of fucoxanthin were significantly reversed by EX527 (a selective inhibitor of Sirt1) or si-Sirt1. In conclusion, our study investigated the protective effect of fucoxanthin against renal I/R injury, and the underlying mechanism may be related to the activation of the Sirt1/Nrf2/HO-1 signaling pathway by fucoxanthin to attenuate oxidative stress-induced apoptosis.

Pin1 aggravates renal injury induced by ischemia and reperfusion in rats via Nrf2/HO-1 mediated endoplasmic reticulum stress

Purpose: To investigate the role of peptidyl-prolyl cis/trans isomerase 1 (Pin1) on renal ischemia-reperfusion (I/R) injury and underlying mechanism. Methods: By establishing the in vitro and in vivo models of renal I/R, the role of Pin1 was explored by using molecular assays. Results: In renal I/R, endogenous Pin1 level was up-regulated in I/R-impaired kidney. Suppression of Pin1 with juglone afforded protection against I/R-mediated kidney dysfunction, and reduced I/R-induced endoplasmic reticulum (ER) stress in vivo. Consistent with the in vivo results, repression of Pin1 with juglone or gene knockdown with si-Pin1 conferred cytoprotection and restricted hypoxia/reoxygenation (H/R)-driven ER stress in HK-2 cells. Simultaneously, further study uncovered that Nrf-2/HO-1 signals was the association between Pin1 and ER stress in response to renal I/R. In addition, Nrf-2/HO-1 signal pathway was inactivated after kidney exposed to I/R, as indicated by the down-regulation of Nrf-2/HO-1 levels. Furthermore, inhibition of Pin1 remarkably rescued the inactivation ofNrf-2/HO-1. Conclusions: Pin1 modulated I/R-mediated kidney injury in ER stress manner dependent on Nrf2-HO-1 pathway in I/R injury.

Long non-coding RNA CCAT2 promotes prostate cancer cell proliferation and invasion by regulating the Wnt/ß-catenin signaling pathway.

Long non-coding RNA colon cancer associated transcript 2 (CCAT2) is dysregulated in a number of different types of human cancer, and affects cancer progression via the Wnt/ß-catenin signaling pathway. However, the roles of CCAT2 and the Wnt/ß-catenin signaling pathway in prostate cancer (PCa) are not completely understood. The present study aimed to investigate the potential mechanism of CCAT2 in PCa. In the present study, the reverse transcription-quantitative PCR (RT-qPCR) results indicated that CCAT2 expression was significantly upregulated in PCa tissues, and DU145 and PC3 cell lines compared with normal prostate tissues and the epithelial RWPE-1 cell line, respectively. Functional assays indicated that CCAT2 downregulation inhibited DU145 and PC3 cell proliferation, cell cycle, migration and invasion. In addition, the luciferase reporter assay, RT-qPCR and western blotting results indicated that CCAT2 regulated transcription factor 7 like 2 (TCF7L2) expression by binding to microRNA-217. Further western blotting and TOPFlash assays indicated that CCAT2-knockdown inhibited the Wnt/ß-catenin signaling pathway in DU145 and PC3 cell lines by inhibiting the expression of TCF7L2. However, CCAT2-knockdown-mediated effects were reversed by the Wnt/ß-catenin signaling pathway activator lithium chloride (LiCl). Further cell experiments suggested that LiCl treatment reversed CCAT2-knockdown-mediated inhibition of PCa cell proliferation, cell cycle, epithelial-mesenchymal transition, migration and invasion. Overall, the results indicated that CCAT2 regulated PCa via the Wnt/ß-catenin signaling pathway; therefore, CCAT2 may exhibit key role during the progression of PCa and may serve as a therapeutic target for the disease.

Effect of ozone oxidative preconditioning on oxidative stress injury in a rat model of kidney transplantation.

The aim of the present study was to investigate the protective effect of ozone oxidative preconditioning (OOP) on renal oxidative stress injury in a rat model of kidney transplantation. Thirty-six male Sprague Dawley (SD) rats were randomly divided into three groups: A sham (S) group, a kidney transplantation (KT) group and an OOP and kidney transplantation (OOP+KT) group. In the S group, the rats' abdomens were opened and closed without transplantation. In the KT group, the rats received a left kidney from donor SD rats. In the OOP+KT group, donor SD rats received 15 OOP treatments by transrectal insufflations (1 mg/kg), once a day, at an ozone concentration of 50 µg/ml, before the kidney transplantation. Twenty-four hours after transplantation, the parameters of renal function of the recipients were measured. The morphology and pathological effects of renal allograft were examined using hematoxylin and eosin staining, periodic acid-Schiff staining, a terminal deoxynucleotidyl transferase dUTP nick end labeling assay and immunohistochemistry. Markers of oxidative stress were also detected using the thiobarbituric acid method, and expression levels of Nrf-2 and HO-1 were determined by western blot analysis. Blood urea nitrogen and creatinine levels were significantly decreased in the OOP+KT group compared with the KT group, and the morphology and pathological changes of renal allograft were also less severe. Meanwhile, the renal allograft cell apoptosis index was significantly higher in the KT group compared to the OOP+KT group (P<0.05). Levels of superoxide dismutase, glutathione and catalase in the renal allografts were significantly higher in the OOP+KT group compared to those in the KT group (P<0.05), while malondialdehyde levels were significantly lower in the OOP+KT group compared to those in the KT group (P<0.05). Western blot analysis indicated that the expression levels of nuclear factor erythroid 2-related factor 2 (Nrf-2) and heme oxygenase 1 (HO-1) were significantly higher in the OOP+KT compared to the KT group (P<0.05). In conclusion, the mechanism by which OOP alleviates oxidative stress injury in renal transplantation may be related to the activation of the signaling pathways of Nrf-2/HO-1 and inhibition of renal tubular epithelial cell apoptosis.

Metformin alleviated EMT and fibrosis after renal ischemia-reperfusion injury in rats.

PURPOSE: The purpose of this study is to assess the potential effects of metformin on the development of EMT and tubulointerstitial fibrosis 12 weeks after acute renal ischemia-reperfusion. METHODS: Male Sprague-Dawley rats were randomly assigned to four groups: Sham, IRI, transient administration of metformin (TAM), and continuous administration of metformin (CAM). Metformin was administered i.p. at a dose of 125 µg kg (- 1) d( - 1) 3 d prior to suffering from IRI (TAM), or from 3 d before suffering from IRI to 12 weeks after reperfusion (CAM). Renal function, histology, and expressions of IL-6, TNF-α, α-SMA, TGF-ß1, Vimentin, and E-cadherin were analyzed. RESULTS: Tubulointerstitial fibrosis worsened further in IRI, accompanied by the increased expressions of interleukin-6, TNF-α, α-SMA, TGF-ß1, Vimentin, and loss of E-cadherin. Although there were no significant differences between IRI and TAM (p > 0.05). Compared with the IRI, expressions of IL-6, TNF-α, α-SMA, TGF-ß1, and Vimentin were reduced and the expression of E-cadherin was restored in CAM (p < 0.05). CAM also significantly promoted activation of AMPK (p < 0.05), which showed no difference among Sham, IRI, and TAM (p > 0.05). CONCLUSIONS: CAM significantly attenuated tubulointerstitial fibrosis and EMT in rats, potentially via activation of AMPK and down-regulation of TGF-ß1.

Inhibition of LSD1 by Pargyline inhibited process of EMT and delayed progression of prostate cancer in vivo.

Recently, lysine-specific demethylase 1 (LSD1) was identified as the first histone demethylase. LSD1 interacted with androgen receptor (AR) and promoted androgen-dependent transcription of target genes, such as PSA, by ligand-induced demethylation of mono- and dimethylated histone H3 at Lys 9 (H3K9). Meanwhile, the phenomenon of epithelial-mesenchymal transition (EMT) had received considerable attention in tumor recurrence and metastasis. This study examined the effect of Pargyline (an inhibitor of LSD1) on the process of EMT in vitro and in vivo. SCID mice were injected subcutaneously with LNCap cells. Pargyline was given intraperitoneally or not after castration (implemented with Bilateral orchidectomy), then PSA levels in serum and tumor were determined to assess time to androgen-independent progression. The results showed that LSD1 expression was up-regulated when PCa progressed to Castration Resistant Prostate Cancer (CRPC). Pargyline reduced LNCap cells migration and invasion ability, and inhibited the process of EMT by up-regulating expression of E-cadherin, and down-regulating expressions of N-cadherin and Vimentin in vitro and in vivo. Although, Pargyline did not change the level of AR, it reduced PSA expression both in vitro and in vivo. Furthermore, Pargyline delayed prostate cancer transition from androgen-dependent to androgen-independent state (CRPC). These findings indicated that inhibition of LSD1 might be a promise adjunctive therapy with androgen deprivation therapy (ADT) for locally advanced or metastatic prostate cancer.

Metformin attenuated the inflammation after renal ischemia/reperfusion and suppressed apoptosis of renal tubular epithelial cell in rats.

PURPOSE: To investigate the effect of metformin on renal tubular epithelial cell apoptosis and inflammation after kidney ischemia/ reperfusion in rats. METHODS: Eighteen SD rats were randomly divided into three groups: Sham (S), Ischemia/reperfusion (I/R), and Metformin (E). Before establishing the I/R model, group E was administered metformin for three days, while groups S and I/R were administered equal volumes of saline. After three days, a right nephrectomy was performed on all groups, after which the left kidneys of groups E and I/R rats were subjected to 45 min renal ischemia. Renal function, histology, and cell apoptosis were assessed. AMPK, pAMPK, COX-2, and Caspase 3 were also detected. RESULTS: Compared to I/R group, Caspase 3 and COX-2 levels were decreased in group E. COX-2, Caspase3 and pAMPK levels were higher in groups E and I/R than in group S. The pAMPK level of group E was higher than that of I/R group, while COX-2 and caspase 3 were lower in group E than they were in the other groups. There was no significant difference between E and I/R groups in AMPK levels. CONCLUSION: Metformin preconditioning attenuated the inflammation caused by ischemia/reperfusion and inhibited the apoptosis of renal tubular epithelial cells.

Metformin attenuated the inflammation after renal ischemia/reperfusion and suppressed apoptosis of renal tubular epithelial cell in rats

PURPOSE:To investigate the effect of metformin on renal tubular epithelial cell apoptosis and inflammation after kidney ischemia/ reperfusion in rats.METHODS:Eighteen SD rats were randomly divided into three groups: Sham (S), Ischemia/reperfusion (I/R), and Metformin (E). Before establishing the I/R model, group E was administered metformin for three days, while groups S and I/R were administered equal volumes of saline. After three days, a right nephrectomy was performed on all groups, after which the left kidneys of groups E and I/R rats were subjected to 45 min renal ischemia. Renal function, histology, and cell apoptosis were assessed. AMPK, pAMPK, COX-2, and Caspase 3 were also detected.RESULTS:Compared to I/R group, Caspase 3 and COX-2 levels were decreased in group E. COX-2, Caspase3 and pAMPK levels were higher in groups E and I/R than in group S. The pAMPK level of group E was higher than that of I/R group, while COX-2 and caspase 3 were lower in group E than they were in the other groups. There was no significant difference between E and I/R groups in AMPK levels.CONCLUSION:Metformin preconditioning attenuated the inflammation caused by ischemia/reperfusion and inhibited the apoptosis of renal tubular epithelial cells.

Oxymatrine ameliorates renal ischemia-reperfusion injury from oxidative stress through Nrf2/HO-1 pathway.

PURPOSE: To investigate if oxymatrine pretreatment could ameliorate renal I/R injury induced in rats and explore the possible role of oxymatrine in Nrf2/HO-1 pathway. METHODS: Unilaterally nephrectomized rats were insulted by I/R in their left kidney. Twenty four rats were randomly divided into three groups: sham group, I/R + saline-treated group, I/R + OMT-treated group. Oxymatrine or vehicle solution was administered intraperitoneally injected 60 min before renal ischemia, respectively. Renal function, histology, makers of oxidative stress, cell apoptosis and Nrf2/HO-1 expressions were assessed. RESULTS: Oxymatrine pretreatment exhibited an improved renal functional recovery, alleviated histological injury and oxidative stress, inhibiting tubular apoptosis, and accompanied by upregulated the expression of Nrf2/HO-1 proteins. CONCLUSION: Oxymatrine may attenuate renal ischemia/reperfusion injury, and this renoprotective effect may be through activating the Nrf2/HO-1 pathway.

Oxymatrine ameliorates renal ischemia-reperfusion injury from oxidative stress through Nrf2/HO-1 pathway

PURPOSE: To investigate if oxymatrine pretreatment could ameliorate renal I/R injury induced in rats and explore the possible role of oxymatrine in Nrf2/HO-1 pathway. METHODS: Unilaterally nephrectomized rats were insulted by I/R in their left kidney. Twenty four rats were randomly divided into three groups: sham group, I/R + saline-treated group, I/R + OMT-treated group. Oxymatrine or vehicle solution was administered intraperitoneally injected 60 min before renal ischemia, respectively. Renal function, histology, makers of oxidative stress, cell apoptosis and Nrf2/HO-1 expressions were assessed. RESULTS: Oxymatrine pretreatment exhibited an improved renal functional recovery, alleviated histological injury and oxidative stress, inhibiting tubular apoptosis, and accompanied by upregulated the expression of Nrf2/HO-1 proteins. CONCLUSION: Oxymatrine may attenuate renal ischemia/reperfusion injury, and this renoprotective effect may be through activating the Nrf2/HO-1 pathway. .

The protective effect of nesfatin-1 against renal ischemia-reperfusion injury in rats.

INTRODUCTION: The pathogenetic mechanisms underlying ischemia-reperfusion (I/R) injury involve oxidative stress, inflammation and apoptosis. Nesfatin-1, a novel peptide, has been reported to possess antioxidant, anti-inflammatory and anti-apoptic properties. The study was to examine the potential protective effects of nesfatin-1 on renal I/R injury. MATERIALS AND METHODS: I/R model was induced by placing a clamp across left renal artery for 45 min followed by 24 h reperfusion, along with a contralateral nephrectom. Twenty-four rats divided into three groups: sham-operated group, vehicle-treated I/R and nesfatin-1-treated I/R. Nesfatin-1 was intraperitoneally injected 30 min before renal ischemia. We harvested serum and kidneys at 24 h after reperfusion. Renal function and histological changes were assessed. Marker of oxidative stress and cells in kidney were also evaluated. RESULTS: The animals with nesfatin-1 significantly improved renal functional and histologic lesions induced by I/R injury. The malondialdehyde (MDA) level decreased, whereas superoxide dismutase (SOD) and catalase (CAT) activities were significantly increased. Moreover, nesfatin-1-treated rats had a markedly decrease in apoptotic tubular cells, as well as a decrease in caspase-3 activity and an increase in the bcl-2/Bax ratio. CONCLUSIONS: This is the first evidence that nesfatin-1 treatment ameliorates acute renal I/R injury by suppressing oxidative stress and cell apoptosis. Therefore, it is promising as a potential therapeutic agent for renal IR injury.

Relationship between LSD1 expression and E-cadherin expression in prostate cancer.

PURPOSE: To investigate the relationship between the expression of LSD1 and E-cadherin in prostate cancer and their prognostic significance. METHODS: The expression of LSD1 and E-cadherin in prostate cancer was detected using immunohistochemistry, and the relationship between the expressions of these two molecules was analyzed by correlation analysis. Furthermore, LNCap cell line was treated with Pargyline (an inhibitor of LSD1), and Western blot was used to analyze LSD1 and E-cadherin expression. RESULTS: LSD1 expression increased significantly in prostate cancer specimens compared with benign prostatic hyperplasia (P < 0.05). Further analysis testified that LSD1 expression was positively correlated with higher Gleason Score, distant metastases, and poor prognosis (P < 0.05). Nevertheless, E-cadherin expression decreased significantly in prostate cancer specimens compared with benign prostatic hyperplasia (P < 0.05) and was negatively correlated with higher Gleason Score, distant metastases (P < 0.05). Correlation analysis revealed that LSD1 expression was negatively correlated with E-cadherin expression in prostate cancer (rs = -0.486, P = 0.001). Positive LSD1 expression and negative E-cadherin expression were significantly correlated with high 2-year progression (occurrence of castration-resistant prostate cancer) rate and low 5-year survival rate (P < 0.05). Moreover, Pargyline inhibited activity of LSD1 and up-regulated E-cadherin expression. CONCLUSION: High LSD1 expression combined with low E-cadherin expression might be predictors of prostate cancer progression and metastasis. Inhibition of LSD1 may be a potential therapeutic target for prevention of prostate cancer.