Protective effects of the AKT activator SC79 on renal ischemia-reperfusion injury.
3
Citation
26
Reference
10
Related Paper
Citation Trend
Abstract:
SC79, an AKT activator, has been reported to protect experimental ischemia-elicited neuronal death, brain injury, and myocardiocyte hypoxia/reoxygenation (H/R) injury. However, the protection of SC79 from renal ischemia-reperfusion (I/R) injury and the precise mechanisms involved are unknown. Here, we investigated the effects of SC79 in renal tubular epithelial cells in vitro and in mouse kidney in vivo following hypoxia-reoxygenation (H/R) and renal I/R injury.The kidneys of Sprague-Dawley rats were subjected to 30 min of warm ischemia followed by 24 h of reperfusion. Murine renal tubular epithelial NRK-52E cells were subjected to hypoxia for 6 h and reoxygenation for 24 h. The NRK-52E cells and the renal I/R injury model were treated with SC79 and/or LY294002 at different times and concentrations. Serum creatinine (Cr) concentration, renal histology, cellular viability, and cell apoptosis were assessed. Levels of phospho-Akt, bad, Bim, bax, bcl-2, and bcl-XL in NRK-52E cells and renal tissues were determined by western blotting.SC79 improved viability and inhibited apoptosis in NRK-52E cells following H/R. SC79 decreased serum Cr and markedly improved pathology and decreased cell apoptosis in kidneys following I/R. In addition, SC79 promoted the expression of phospho-Akt, bcl-2, and bcl-XL, and decreased the expression levels of bid, bax, and bim. PI3K inhibitor (LY294002) pre-treatment completely abolished these effects of SC79.The protective role of SC79 against H/R of NRK-52E cells or renal I/R injury is related to activation of phosphorylation of AKT, resulting in a decrease in the pro-apoptotic proteins bim, bax, and bad and an increase in the anti-apoptotic proteins bcl-2 and bcl-XL induced by cell H/R and renal I/R injury.Keywords:
Hypoxia
LY294002
Cite
Objective This study aims to investigate the relationship between PI3K/AKt signaling pathway and the protection provided by LPA for cisplatin-induced apoptosis in ovarian carcinoma cells. Methods MTT assay was used to assess the proliferative activity of SKOV3 cells treated by DDP with or without LPA and LY294002. Hochest33258 was used to observe the apoptotic cells by fluorescence staining. FCM was used to detect the apoptosis of SKOV3 cells treated by DDP with LPA and LY294002. The specific DNA ladder pattern was used to confirm the apoptotic event. Western blotting was employed to detect the expression the levels of phosphorylated Akt protein. Results It revealed that LPA decreased the growth inhibition induced by DDP,but LPA+LY294002 increased the growth inhibition induced by DDP. In addition,it was also found that the apoptosis percentage in the cells treated with LPA+LY294002+DDP only exposed to LPA+DDP. Neither the apoptotic body nor the specific DNA ladder pattern for apoptotic cells was found in the cells exposed to LPA,but they were seen in the cells which were exposed to LPA+LY294002.Western blotting showed that LPA increased the expression level of expression of phosphorylated Akt protein,but LY294002 decreased. Conclusion LPA inhibit the apoptosis induced by DDP through the PI3K/AKt signaling pathway.
LY294002
MTT assay
Cite
Citations (0)
Cite
Citations (7)
In this study we demonstrated that Triticuside A, one of the flavonoid compounds isolated from wheat bran, induced apoptosis and inhibited proliferation of human breast cancer cells. Triticuside A inhibited the proliferation of human breast cancer cells (MCF-7 and MDA-MB-231) in a dose-dependent manner but barely showed cytotoxicity to the normal human fibroblasts. Triticuside A-induced apoptosis was accompanied by a significant decrease of Mcl-1 and Bcl-2 proteins and by an increase of cleavage of caspases-3, -7, -9, and PARP. Triticuside A also suppressed the level of phospho-Akt and its downstream targets, mTOR and P70 S6 kinase. LY294002, a specific inhibitor of PI3K, significantly enhanced the Triticuside A-induced apoptosis. Moreover LY294002 not only downregulated the level of phospho-Akt but also enhanced the inhibition of Mcl-1 expression when combined with Triticuside A. Our results demonstrate for the first time the specific apoptogenic activity of Triticuside A in tumor cells and involvement of the mitochondrial apoptosis pathway and Akt/mTOR signaling pathway. Thus, Triticuside A may be a potentially useful wheat bran component that can be used for prevention or treatment of breast cancer.
LY294002
Cite
Citations (14)
Background and Objectives. Bone mesenchymal stem cells (BMSCs) play a vital role in skin wound healing and skin regeneration through proliferation, migration, and paracrine interactions. A previous study indicated that ginsenoside Rb1 acted as a vital antidotal component which antagonized the oxidative stem cell. However, the effect and mechanism of ginsenoside Rb1-mediated BMSC migration remained unknown. Methods. Wound-healing assay and Transwell assay were utilized to evaluate the effect of ginsenoside Rb1 on the migration of BMSCs. RT-PCR and Western blotting were performed to evaluate the expression of stromal-derived factor 1 (SDF-1), C-X-C chemokine receptor type 4 (CXCR4), phosphatidylinositol 3-kinase (PI3K), and protein kinase B (PKB; AKT). Results. Ginsenoside Rb1 significantly enhanced the migration of BMSCs through the activation of SDF-1, CXCR4, p-PI3K/PI3K, and p-Akt/Akt relative expression. Furthermore, this stimulus was blocked by the pretreatment with AMD3100 and LY294002. Conclusions. Ginsenoside Rb1 facilitated the migration of BMSCs through the activation of the SDF-1/CXCR4 axis and PI3K/Akt pathway.
Cite
Citations (6)
Hypoxia inducible factor 1 is regulated by the appearance of the HIF‐1α subunit. HIF‐1α is subjected to proteasomal destruction or enhanced protein translation, which requires the phosphatidylinositol 3‐kinase (PI3K)/Akt pathway. We investigated how PI3K/Akt and glycogen synthase kinase 3β (GSK3β) affect HIF‐1α in human RKO cells under prolonged periods of severe hypoxia/anoxia. 16‐ to 32‐h lasting incubations attenuated Akt activity and decreased HIF‐1α protein. This was reproduced by blocking PI3K with LY294002. GSK3β inhibition by indirubins circumvented the effect of hypoxia/anoxia or LY294002 on HIF‐1α. Ruling stability regulation of HIF‐1α protein and/or enhanced transcription of HIF‐1α mRNA via GSK3β inhibition out is suggestive for translational modulation of HIF‐1α under the influence of GSK3β.
Hypoxia
LY294002
GSK3B
Cite
Citations (40)
Objective To investigate the role of phosphoinositide 3-kinases(PI3K)/Akt signaling pathway in TRAIL-induced cell apoptosis,and the effect of oxaliplatin on TRAIL-induced apoptosis in gastric cancer BGC823 cells.Methods Cell proliferation was measured using MTT assay.Cell apoptosis was determined by flow cytometry.The expression of Akt and phosphor-Akt were determined by Western blotting.Results 100 ng/mL TRAIL caused little cell apoptosis in BGC823 cells.TRAIL activated PI3K/Akt pathway.Pretreated with PI3K in-hibitor LY294002(25 μmol/L)for 1 h followed by exposure to TRAIL for 16 h,the cell apoptosis was obviously higher(12.7%±3.1% vs 3.5%±1.1%,P 0.05)than that without the treatment of LY294002.Treatment with 38 μg/mL oxaliplatin blocked the activation of PI3K/ Akt signaling,and enhanced the sensitivity of cells to TRAIL,the rate of cell apoptosis increased to 35.5%±4.5%(P 0.05).Conclusion Oxaliplatin enhanced the sensitivity of gastric cancer BGC823 cells to TRAIL by inhibiting TRAIL-induced the activation of PI3K/Akt path-way.
MTT assay
LY294002
Cite
Citations (0)
To investigate the role of p38MAPK and PI3K/AKT pathways in mitomycin (MMC)-induced apoptosis in the liver stem-like cell line WB-F344.WB-F344 cells were exposed to MMC and apoptosis was evaluated by flow cytometry and DNA fragmentation. Phospho-MAPK and phospho-PI3K/AKT were detected by western blotting.MMC induced apoptosis in WB-F344 cells at 6h after addition of MMC; the maximum level of apoptosis was reached at 24h after MMC exposure. The apoptosis effects of MMC were concentration dependent and inhibited when the PI3K pathway was abolished by the specific inhibitor LY294002, but not inhibited when the p38MAPK pathway was abolished by inhibitor SB203508.Apoptosis of WB-F344 cells can be induced by MMC.Although MMC can activate both the PI3K/AKT and p38MAPK pathways, the apoptosis effect of MMC occurs via a PI3K pathway and is not dependent on the p38MAPK pathway.
LY294002
Mitomycin C
Cite
Citations (1)
Objective:To clarify the effects of PI3K/Akt pathway on cardiomyocytes subjected to ischemia and hypoxia.Methods: Cardiomyocytes were cultured in vitro.Viabilities of cardiomyocytes,lactate dehydrogenase(LDH)leaking and ratio of propidium io- dide(PI)staining positive cells were observed to test the effects of LY294002,a specific inhibitor of phosphatidylinositol 3-kinase,when exposed to stimulation of isehemia and hypoxia.Results:Viabilities of cardiomyocytes subjected to ischemia and hypoxia by the inhibi- tion of PI3K/Akt pathway were significantly lower and LDH leak-age and ratio of PI staining positive cells were significantly higher than those without PI3K/Akt pathway inhibition(P0.01 ).Conclusion:LY294002 can aggravate the injury of cardiomyocytes subjected to is- ehemia and hypoxia,which suggests that the PI3K/Akt pathway can protect cardiomyocytes from injury of ischemia and hypoxia.
LY294002
Hypoxia
Cite
Citations (0)
To explore the role of the phosphatidylinositol 3 kinase/protein kinase B (PI3K/Akt) pathway in silica-induced α-SMA (α smooth muscle actin) expression in HEB (human bronchial epithelial) cell.The cultured HBE cells were divided into 5 groups: control, silica, PI3K inhibitor (Ly294002), both PI3K inhibitor (Ly294002) and silica at the same time and the inhibitor 24 h ahead of silica. The final concentrations of PI3K inhibitor and silica were 10 µmol/L and 100 µg/ml, respectively. Western blots were used to detect protein expressions of Akt, p-Akt, TGF-β and α-SMA. The location and expression of α-SMA were measured by immunofluorescence assay.HBE cell line exposed to silica can induce Akt phosphorylation, in which expressions of p-Akt were up regulated 1 times at 48 and the highest at 72 h. The expressions of TGFβ increased remarkably at 12 h and the peak at 48 h after silica exposure, while the expressions of α-SMA increased at 24 h and the highest at 72 h. However, the PI3K inhibitor (Ly294002) significantly down regulated α-SMA expression. When the cell line exposed to the PI3K inhibitor ahead of silica 24 h, the expressions of p-Akt and α-SMA were more remarkably down regulated which were decreased 1.5 times and 7.6 times respectively compare to silica exposure group. But no significant changes were found for TGFβ expressions. The immunofluorescence assay showed that silica can induce α-SMA expression, which located in cytoplasma, and PI3K inhibitor can decrease the expression.Silica induced α-SMA expression in HBE cell line is by targeting the PI3K/Akt pathway and PI3K inhibitor can repress α-SMA expression.
LY294002
Cite
Citations (1)
Boswellic acids, a type of pentacyclic triterpenoids, have been shown to induce apoptosis in colon cancer cells. The phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) pathway is crucial for cell proliferation and survival. Whether the apoptotic effects of boswellic acid could be affected by inhibition of PI3K/Akt pathway was examined.Colon cancer HT29 cells were treated with 3-acetyl-11-keto-beta boswellic acid AKBA in the absence and presence of LY294002 or Wortmanin, inhibitors of PI3K. Apoptosis was determined by flow cytometry and caspase assay. The activation of Akt was examined by Western blot.AKBA at 30 microM only slightly induced apoptosis. Preincubation of the cells with LY294002 or wortmannin significantly enhanced the AKBA-induced apoptosis up to 20-fold. Further study showed that at the doses used, AKBA induced phosphorylation of Akt at both Ser473 and Thr308 positions, indicating an activation of the PI3K/Akt pathway.AKBA may activate the PI3K/Akt pathway and inhibition of the PI3K pathway significantly enhances AKBA-induced apoptosis.
Wortmannin
LY294002
Cite
Citations (39)