Effect of L-carnitine on ferroptosis in renal tubular epithelial cells induced by calcium oxalate / 中华泌尿外科杂志

Objective:To investigate the effect of L-carnitine on calcium oxalate-induced ferroptosis in renal tubular epithelial cells (HK-2).Methods:The effects of calcium oxalate(0, 2, 4 and 8 mmol/L) on the expression of ferroptosis-related protein long chain fatty acyl-CoA synthetase 4 (ACSL4), cystine/glutamate transporter(XCT) and glutathione peroxidase 4 (GPX4) in HK-2 cells were detected by Western blotting. The experiment was then divided into four groups: ①control group, cells were cultured in normal medium for 12 hours, then continued to use normal medium; ②L-carnitine group, cells were pretreated with medium containing 5mmol/L L-carnitine for 12 hours, then changed to medium containing 5mmol/L L-carnitine; ③calcium oxalate group, cells were cultured in normal medium for 12 hours, and then replaced with medium containing 4 mmol/L calcium oxalate; ④calcium oxalate+ L-carnitine group, the cells were pretreated with medium containing 5mmol/L L-carnitine for 12 h, and then replaced with 5mmol/L L-carnitine and 4mmol/L calcium oxalate medium. After changing the culture medium for 24 hours, the cells or supernatants were collected, and the expression levels of ferroptosis-related protein quinone oxidoreductase (NQO1), ACSL4, XCT and GPX4 were detected by Western blotting. The levels of superoxide dismutase (SOD), glutathione (GSH) and malondialdehyde were detected by corresponding kit, and the level of reactive oxygen species in cells was detected by reactive oxygen species kit.Results:The results of Western blotting showed that the expression of ACSL4 protein in 0, 2, 4, 8 mmol/L calcium oxalate was 0.37±0.16, 0.68±0.16, 0.73±0.09, 0.89±0.03 respectively. The expression of XCT protein was 1.11±0.10, 0.91±0.14, 0.83±0.09, 0.80±0.07, respectively. The expression of GPX4 protein was 1.23±0.13, 0.99±0.17, 0.81±0.05, 0.72±0.06, respectively. Compared with 0mmol/L group, the expression of ACSL4 protein increased and the expression of XCT and GPX4 decreased in 2, 4 and 8 mmol/L groups, and the difference was more significant between 4 mmol/L group and 0 mmol/L group. So 4 mmol/L was taken as the optimal concentration for follow-up experiment. The levels of NQO1 in control group, L-carnitine group, calcium oxalate group and calcium oxalate+ L-carnitine group were (0.36±0.06, 0.54±0.05, 0.76±0.07, 0.90±0.03) respectively. There was significant difference between L-carnitine group and control group ( P<0.05). There was significant difference between calcium oxalate group and control group ( P<0.05). There was significant difference between calcium oxalate group and control group ( P<0.01). There was significant difference between calcium oxalate + L-carnitine group and calcium oxalate group ( P<0.05). The levels of ACSL4 in control group, L-carnitine group, calcium oxalate group and calcium oxalate + L-carnitine group were (0.66±0.10, 0.58±0.08, 0.99±0.03, 0.77±0.09) respectively. There was no significant difference between L-carnitine group and control group(P>0.05). There was significant difference between calcium oxalate group and control group ( P<0.01). There was significant difference between calcium oxalate + L-carnitine group and calcium oxalate group ( P<0.05). The levels of XCT in control group, L-carnitine group, calcium oxalate group and calcium oxalate + L-carnitine group were (0.93±0.08, 0.85±0.07, 0.76±0.06, 0.99±0.05). There was no significant difference between L-carnitine group and control group (P>0.05). There was significant difference between calcium oxalate group and control group ( P<0.01). There was significant difference between calcium oxalate + L-carnitine group and calcium oxalate group ( P<0.05). The levels of GPX4 in control group, L-carnitine group, calcium oxalate group and calcium oxalate + L-carnitine group were (1.10±0.09, 1.09±0.09, 0.85±0.03, 0.99±0.02) respectively. There was no significant difference between L-carnitine group and control group( P>0.05). There was significant difference between calcium oxalate group and control group ( P<0.01). There was significant difference between calcium oxalate + L-carnitine group and calcium oxalate group ( P<0.05). The levels of LDH in control group, L-carnitine group, calcium oxalate group and calcium oxalate + L-carnitine were (100.00±5.37)%, (99.50±6.38)%, (153.77±6.06)% and (132.50±5.58)%, respectively. There was no significant difference between L-carnitine group and control group( P>0.05). There was significant difference between calcium oxalate group and control group ( P<0.01). There was significant difference between calcium oxalate + L-carnitine group and calcium oxalate group ( P<0.05). The SOD levels in control group, L-carnitine group, calcium oxalate group and calcium oxalate + L-carnitine group were (100.00±5.79)%, (105.80±3.26)%, (44.74±7.60)% and (85.01±5.15)%, respectively. There was no significant difference between L-carnitine group and control group( P>0.05). There was significant difference between calcium oxalate group and control group ( P<0.01). There was significant difference between calcium oxalate + L-carnitine group and calcium oxalate group ( P<0.05). The levels of GSH in control group, L-carnitine group, calcium oxalate group and calcium oxalate + L-carnitine group were (100.00±4.73)%, (107.10±5.48)%, (53.49±3.98)% and (85.18±5.48)%, respectively. There was no significant difference between L-carnitine group and control group( P>0.01). There was significant difference between calcium oxalate group and control group ( P<0.01). There was significant difference between calcium oxalate + L-carnitine group and calcium oxalate group ( P<0.01). The levels of MDA in control group, L-carnitine group, calcium oxalate group and calcium oxalate + L-carnitine group were (100.00±2.36)%, (98.00±11.10)%, (129.11±2.59)% and (113.35±5.79)%, respectively. There was no significant difference between L-carnitine group and control group( P>0.05). There was significant difference between calcium oxalate group and control group ( P<0.01). There was significant difference between calcium oxalate + L-carnitine group and calcium oxalate group ( P<0.01). The fluorescence intensity of ferrous ion in control group, calcium oxalate group and calcium oxalate + L-carnitine group was (39.77±0.68) AU, (68.40±3.14) AU and (48.60±4.30) AU, respectively. There was significant difference between calcium oxalate group and control group ( P<0.01). There was significant difference between calcium oxalate + L-carnitine group and calcium oxalate group ( P<0.05). The fluorescence intensity of reactive oxygen species in control group, calcium oxalate group and calcium oxalate + L-carnitine group was (63.98±9.41) AU, (145.41±8.39) AU and (85.37±4.51) AU, respectively. There was significant difference between calcium oxalate group and control group ( P<0.01). There was significant difference between calcium oxalate + L-carnitine group and calcium oxalate group ( P<0.01). Transmission electron microscopy results showed that mitochondria were wrinkled, cristae were broken or disappeared in the calcium oxalate group compared to the control group, and a double-layer membrane structure was evident. DAPI staining showed that compared with the control group, some of the nuclei in the calcium oxalate group were significantly more damaged, while compared with the calcium oxalate group, the nuclei in the calcium oxalate + L-carnitine were significantly less damaged. The results of crystal adhesion test showed that compared with the control group, calcium oxalate crystals in the calcium oxalate group adhered to the cells in black-like particles and formed clusters. Compared with the calcium oxalate group, the calcium oxalate + L-carnitine showed less black particles adhering to the cells. Conclusions:L-carnitine may reduce the effects of oxidative stress and ferroptosis induced by calcium oxalate, thus reducing cell damage and crystal adhesion.

Leonurine inhibits ferroptosis in renal tubular epithelial cells by activating p62/Nrf2/HO-1 signaling pathway / 中国中药杂志

To investigate the protective effect and the potential mechanism of leonurine(Leo) against erastin-induced ferroptosis in human renal tubular epithelial cells(HK-2 cells), an in vitro erastin-induced ferroptosis model was constructed to detect the cell viability as well as the expressions of ferroptosis-related indexes and signaling pathway-related proteins. HK-2 cells were cultured in vitro, and the effects of Leo on the viability of HK-2 cells at 10, 20, 40, 60, 80 and 100 μmol·L~(-1) were examined by CCK-8 assay to determine the safe dose range of Leo administration. A ferroptosis cell model was induced by erastin, a common ferroptosis inducer, and the appropriate concentrations were screened. CCK-8 assay was used to detect the effects of Leo(20, 40, 80 μmol·L~(-1)) and positive drug ferrostatin-1(Fer-1, 1, 2 μmol·L~(-1)) on the viability of ferroptosis model cells, and the changes of cell morphology were observed by phase contrast microscopy. Then, the optimal concentration of Leo was obtained by Western blot for nuclear factor erythroid 2-related factor 2(Nrf2) activation, and transmission electron microscope was further used to detect the characteristic microscopic morphological changes during ferroptosis. Flow cytometry was performed to detect reactive oxygen species(ROS), and the level of glutathione(GSH) was measured using a GSH assay kit. The expressions of glutathione peroxidase 4(GPX4), p62, and heme oxygenase 1(HO-1) in each group were quantified by Western blot. RESULTS:: showed that Leo had no side effects on the viability of normal HK-2 cells in the concentration range of 10-100 μmol·L~(-1). The viability of HK-2 cells decreased as the concentration of erastin increased, and 5 μmol·L~(-1) erastin significantly induced ferroptosis in the cells. Compared with the model group, Leo dose-dependently increased cell via-bility and improved cell morphology, and 80 μmol·L~(-1) Leo promoted the translocation of Nrf2 from the cytoplasm to the nucleus. Further studies revealed that Leo remarkably alleviated the characteristic microstructural damage of ferroptosis cells caused by erastin, inhibited the release of intracellular ROS, elevated GSH and GPX4, promoted the nuclear translocation of Nrf2, and significantly upregulated the expression of p62 and HO-1 proteins. In conclusion, Leo exerted a protective effect on erastin-induced ferroptosis in HK-2 cells, which might be associated with its anti-oxidative stress by activating p62/Nrf2/HO-1 signaling pathway.

Inhibition of ginsenoside Rb 1 on the epithelial-mesenchymal transition of renal tubular epithelial cells by regulating TGF-β1/Smad3 signaling pathway / 中国药房

OBJECTIVE To study the effects of ginsenoside Rb 1（G-Rb1）on epithelial-mesenchymal transition （EMT）of renal tubular epithelial cells and its potential mechanism. METHODS The growth factor β1（TGF-β1）10 ng/mL was used to induce EMT of human renal tubular epithelial cells HK- 2. The morphological changes of HK- 2 cells were observed after treated with 10， 20，30 μmol/L G-Rb1 for 48 h. The transcriptional activities of biovector SBE in human embryonic kidney cell HEK 293 were determined after 24 h treatment with 1.0，2.5，5.0，10，20，30 μmol/L G-Rb1. Effects of above concentration of G-Rb 1 on the viability of HK- 2 cells were determined after 24 h of treatment. mRNA expressions of α-smooth muscle actin （α-SMA），collagen Ⅰ （COL-Ⅰ）and fibronectin （FN）in HK- 2 cells were detected after treated with 10，20，30 μmol/L G-Rb1 for 24 h. The expressions of α-SMA，Smad3，p-Smad3，COL-Ⅰ，FN and E-cadherin were detected after treated with 10，20，30 μmol/L G-Rb1 for 24 h. RESULTS G-Rb1 of 10-30 μmol/L significantly inhibited TGF-β1-induced EMT in HK- 2 cells and the increase of transcriptional activities of biovector SBE induced by TGF-β1（P＜0.05），but had no effects on relative activities of HK- 2 cells（P＞0.05）. The protein and mRNA expressions of α-SMA，COL-Ⅰ and FN ， the protein expressions of Smad 3 and p-Smad 3 were significantly up-regulated induced by TGF-β1（P＜0.05），while the protein expression of E-cadherin was significantly down- regulated（P＜0.05）；G-Rb1 could effectively reverse aboveprotein or mRNA expressions. CONCLUSIONS G-Rb1 can protect renal tubular epithelial cells from EMT induced byxiezhishen TGF-β1 to a certain extent ，which may be related to inhibiting the activation of TGF-β1/Smad3 signaling pathway.

The role of the fat mass and obesity-associated protein in ischemia-reperfusion injury of human renal tubular epithelial cells / 中华实用儿科临床杂志

Objective:To explore the role of the fat mass and obesity-associated protein (FTO) in human renal tubular epithelial cells (HK-2) suffering ischemia-reperfusion injury (IRI).Methods:The in vitro IRI mo-del was established in HK-2 cells by induction with antimycin A, A23187 and 2-deoxy-D-glucose.The cells were divided into control group and ischemia-reperfusion group (I/R group). The mRNA and protein expressions of FTO, B-cell lymphoma / leukemia 2(Bcl-2)-associated X(Bax), Bcl-2 and cleaved cysteinyl aspartate specific proteinase(cleaved Caspase-3) in HK-2 cells before and after IRI were detected by real-time fluorescent quantitative PCR(qPCR) and Western blot, respectively.Cell apoptosis was measured using flow cytometry.The level ofe N 6-methy-ladenosine (m 6A) RNA was detected by colorimetry. Results:(1) The mRNA expressions of FTO (0.15±0.05 vs.1.00±0.23) and Bcl-2 (0.14±0.07 vs.1.02±0.25) in I/R group were significantly lower than those in control group; While those of Bax (3.10±0.35 vs.1.00±0.13) and cleaved Caspase-3 (4.21±0.56 vs.1.00±0.09) were significantly higher ( t=6.28, 5.84, -9.83, and -9.84, respectively, all P<0.01). (2) The protein expressions of FTO (0.69±0.14 vs.1.37±0.02) and Bcl-2 (0.50±0.12 vs.1.25±0.21) were significantly lower in I/R group than those of control group; While those of Bax (1.04±0.08 vs.0.57±0.06) and cleaved Caspase-3 (0.99±0.05 vs.0.36±0.07) were significantly higher ( t=8.10, 5.49, -8.22, and -12.09, respectively, all P<0.05). (3) Compared with the control group, the apoptosis rate of HK-2 cells in I/R group was significantly higher [(61.70±1.01)% vs.(0.16±0.10)%, t=63.80, P<0.01]. (4) Compared with the control group, the percentage of m 6A modification level in total RNA in I/R group was significantly higher [(3.13±0.21)% vs.(1.10±0.26)%, t=-10.61, P<0.01]. Conclusions:FTO-mediated RNA m 6A modification may affect renal IRI by regulating the apoptosis of HK-2 cells.

Panax notoginseng Saponins Alleviate TGF-β1-induced Renal Tubular Epithelial Cell Injury by Inhibiting Autophagy / 中国实验方剂学杂志

ObjectiveTo investigate the role and mechanism of Panax notoginseng saponins （PNS） in inhibiting transforming growth factor-β1 （TGF-β1）-induced renal tubular epithelial cell injury. MethodNRK-52E renal tubular epithelial cells were cultured and divided into control group， TGF-β1 group，TGF-β1+12.5 mg·L-1 PNS group，TGF-β1+25 mg·L-1 PNS group and TGF-β1+50 mg·L-1 PNS group. After 48 hours of PNS intervention， the cells and the supernatant were collected， and cell morphology was observed by inverted microscope. Western blot was used to detect the expression of epithelial-mesenchymal transition （EMT）-related proteins and autophagy-related proteins. Flow liquid chromatography for multiple protein quantification and flow cytometry were employed to determine the content of inflammatory factors and apoptosis rate， respectively. ResultCompared with the conditions in the control group， after TGF-β1 induction， the cells showed a spindle-shaped change and the expression of E-cadherin was down-regulated （P<0.05）， while the expression of α-smooth muscle actin （α-SMA） was up-regulated （P<0.05）. After PNS treatment， most of the cells tended to be normal and reversed the occurrence of EMT. In addition， compared with the conditions in the control group， the level of TNF-α was increased while that of IL-10 was decreased， with elevated apoptosis rate （P<0.05） in the TGF-β1 group. After PNS treatment， the level of TNF-α was lowered while that of IL-10 was boosted with the increase of the dose， with reduced apoptosis rate （P<0.05）. Moreover， after TGF-β1 induction， the expression of autophagy-related proteins Beclin 1 and LC3Ⅱ/Ⅰ in renal tubular epithelial cells were up-regulated， while PNS inhibited their expression（P<0.05，P<0.01）. ConclusionPNS had a protective effect on TGF-β1-induced renal tubular epithelial cells， and the mechanism might be that it reduced inflammation and apoptosis by inhibiting autophagy， thus alleviating TGF-β1-induced injury.

Effect of hydroxysafflor yellow A on apoptosis of human renal tubular epithelial cells under cold hypoxia and reoxygenation / 中国综合临床

Objective:To investigate the effect of hydroxysafflor yellow A(HSYA) preconditioning group on apoptosis induced by cold hypoxia/reoxygenation (cold H/R) injury in human renal tubular epithelial cells (HK2 cells).Methods:After digestion and passage, HK2 cell lines were divided into Sham group (control group), cold hypoxia and reoxygenation group (cold H/R group, cells cold hypoxia for 4 h, reoxygenation for 4 h), and HSYA preconditioning group (each HSYA subgroup was given different doses of HSYA 0.5 h before hypoxia, and the other operations were the same as the cold H/R group). The cell survival rate was measured by CCK-8 method.The expression of Bcl-2, Bax and Caspase-3 proteins in HK-2 cells were detected by immunocytochemistry and Western blotting.Results:(1) Compared with cold H/R group, different doses of HSYA could improve cell survival rate in different degrees, but only HSYA25 μmol/L group had the most significant effect (74.000±5.500 vs.59.000±3.800, P<0.05). (2) Immunocytochemistry semi-quantitative score: Compared with cold H/R group, the expression of Bax and Caspase-3 in HK2 cells of HSYA25 μmol/L group was significantly decreased(0(0, 1) vs. 8(6, 8), Z=2.041, P<0.05 and (3.400±0.548) vs.(7.800±1.095), t=11.000, P<0.01). The expression of Bcl-2 protein was increased significantly ((6.800±1.095) vs.(1.400±0.548), t=10.590, P<0.01). The ratio of Bcl-2/Bax increased significantly.(3)Western blot was used to detect protein: Compared with the cold H/R group, the protein levels of Bax, Cleaved-Caspase-3 and Pro-caspase-3 of HK2 cells in the HSYA25 μmol/L group were significantly decreased ((0.707±0.012) vs.(0.968±0.117), (0.480±0.009)vs.(0.735±0.005), (0.992±0.008)vs.(1.197±0.005), all P<0.01). The expression of Bcl-2 protein was significantly increased, and the ratio of Bcl-2/Bax was significantly increased ((0.410±0.009) vs.(0.273±0.008), (0.582±0.016) vs (0.282±0.080), all P<0.01). The experimental results were consistent with the immunocytochemistry. Conclusion:HSYA can effectively reduce the damage of HK2 cells after cold hypoxia and reoxygenation.

Effects of Sulforaphane on the Proliferation and Apoptosis of Human Renal Tubular Epithelial Cells Induced by High Glucose and Its Mechanism / 中国药房

OBJECTIVE：To study the effects of sulforaphane on the prolifera tion and apoptosis of human renal tubular epithelial cells HK- 2 induced by high glucose ，and to investigate its mechanism primarily. METHODS ：HK-2 cells were divided into normal group ，high glucose group ，irbesartan group （positive control ，1 μmol/L），sulforaphane low ，medium and high concentration groups （10，20，40 μmol/L）. The cells in normal group were cultured in DMEM medium for 96 hours. T he cells in other groups were cultured in high glucose DMEM medium （containing 40 mmol/L glucose ）for 48 hours. After inducing cell injury，the cells were added with corresponding drugs for 48 hours. Survival rate and apoptotic rate of cells were detected. mRNA expression of cyclin D 1，caspase-3，Bcl-2 and Bax as well as protein expression of p-mTOR ，p-AMPK，p-Akt and p-PI 3K were also determined. In addition ，HK-2 cells were divided into normal group ，high glucose group ，sulforaphane high concentration group（40 μmol/L），acardicin group （AMPK agonist ，1 mmol/L），sulforaphane high concentration+compound C group （sulforaphane 40 μmol/L+AMPK inhibitor compound C 40 μmol/L），perifoxine group （Akt inhibitor ，19.95 μmol/L）、sulforaphane high concentration+SC 79 group（sulforaphane 40 μmol/L+Akt agonist SC79 4 μmol/L）. After cultured with the same method ， protein expression of p-mTOR ，p-AMPK，p-Akt and p-PI 3K were detected in HK- 2 cells. RESULTS ：Compared with normal group，survival rate of HK- 2 cells，mRNA expression of cyclin D 1 and Bcl- 2 as well as protein expression of p-AMPK were decreased significantly in high glucose group （P＜0.05）；apoptotic rate ，mRNA expression of caspase- 3 and Bax ，protein expression of p-mTOR ，p-Akt and p-PI 3K in HK- 2 cells were increased significantly （P＜0.05）. Compared with high glucose group，above indexes of sulforaphane low ，medium and high concentration groups ，irbesartan group were all improved significantly （P＜0.05）；the improvement of above indexes in sulforaphane medium and high concentration groups were significantly better those of sulforaphane low concentration group （P＜0.05）. There was no significant difference in above indexes between sulforaphane high concentration group and irbesartan group （P＞0.05）. Compared with sulforaphane high concentration group，there were no significant difference in the protein expression of p-AMPK ，p-mTOR in acardicin group and p-mTOR ，p-Akt and p-PI 3K in perifoxine group （P＞0.05）；the protein expression of p-AMPK in sulforaphane high concentration+compound C group was decreased significantly （P＜0.05），while the protein expression of p-mTOR was increased significantly （P＜0.05）；the protein expression of p-mTOR 、p-Akt、p-PI3K in sulforaphane high concentration+SC 79 group were increased significantly （P＜ 0.05）. CONCLUSIONS ：Sulforaphane can promote the proliferation of renal tubular epithelial cells and inhibit its apoptosis ；its mechanism may be associated with up-regulating the expression of p-AMPK and down-regulating the expression of p-mTOR ，p-Akt and p-PI 3K.

Exploring molecular mechanisms of fucoidan in improving human proximal renal tubular epithelial cells aging by targeting autophagy signaling pathways / 中国中药杂志

Fucoidan(FPS) is an effective component of the Chinese patent medicine named Haikun Shenxi, which treats schronic renal failure in clinics, and has the potential anti-aging effects. However, it is still unclear whether FPS can improve renal aging, especially the molecular mechanism of its anti-aging. The human proximal renal tubular epithelial cells(HK-2) in vitro were divided into normal group(N), D-gal model group(D), low dose of FPS group(L-FPS), high dose of FPS group(H-FPS) and vitamin E group(VE), and treated by the different measures, respectively. More specifically, the HK-2 cells in each group were separately treated by 1 mL of 1% fetal bovine serum(FBS) or D-galactose(D-gal, 75 mmol·L~(-1)) or D-gal(75 mmol·L~(-1))+FPS(25 μg·mL~(-1)) or D-gal(75 mmol·L~(-1))+FPS(50 μg·mL~(-1)) or D-gal(75 mmol·L~(-1))+VE(50 μg·mL~(-1)). After the treatment for 24 h, firstly, the effects of D-gal on senescence-associated β-galactosidase(SA-β-gal) staining characteristics and klotho, P53 and P21 protein expression le-vels, as well as adenosine monophosphate activated protein kinase(AMPK)-uncoordinated 51-like kinase 1(ULK1) signaling pathway activation in the HK-2 cells were detected, respectively. Secondly, the effects of FPS and VE on SA-β-gal staining characteristics and klotho, P53 and P21 protein expression levels in the HK-2 cells exposed to D-gal were investigated, respectively. Finally, the effects of FPS and VE on microtubule-associated protein 1 light chain 3(LC3) protein expression level and AMPK-ULK1 signaling pathway activation in the HK-2 cells exposed to D-gal were examined severally. The results indicated that, for the HK-2 cells, the dose of 75 mmol·L~(-1) D-gal could induce the changes of SA-β-gal staining characteristics and klotho, P53 and P21 protein expression levels. That is causing cells aging. FPS and VE could both ameliorate the changes of SA-β-gal staining characteristics and klotho, P53 and P21 protein expression levels in the HK-2 cells exposed to D-gal. That is anti-cells aging, here, the functions of FPS and VE are similar. D-gal could not only induce cell aging but also increase LC3Ⅱ, phosphorylated-AMPK(p-AMPK) and phosphorylated-ULK1(p-ULK1) protein expressions, and activate autophagy-related AMPK-ULK1 signaling pathway. FPS and VE could both improve the changes of LC3Ⅱ, p-AMPK and p-ULK1 protein expression levels in the HK-2 cells exposed to D-gal. That is inhibiting autophagy-related AMPK-ULK1 signaling pathway activation. On the whole, for the human proximal renal tubular epithelial cells aging models induced by D-gal, FPS similar to VE, can ameliorate renal cells aging by possibly inhibiting autophagy-related AMPK-ULK1 signaling pathway activation. This finding provides the preliminary pharmacologic evidences for FPS protecting against renal aging.

Canine adipose-derived mesenchymal stem cells and their exosomes in the repair of gentamicin-induced renal tubular epithelial cell injury / 中国组织工程研究

BACKGROUND: Canine kidney injury is characterized by the apoptosis and necrosis of renal tubular epithelial cells. Recent developments in mesenchymal stem cells and their exosomes research have shown great promise for the treatment of kidney injury in humans, rats and mice, but little research has been done on dogs. OBJECTIVE: To investigate the effects of canine adipose-derived mesenchymal stem cells and their exosomes on canine renal tubular epithelial cell injury induced by gentamicin in vitro. METHODS: Canine renal tubular epithelial cells were treated by 5 mmol/L gentamicin sulfate. Subsequently, canine adipose-derived mesenchymal stem cells and their conditional medium and exosomes were co-cultured with damaged canine renal tubular epithelial cells respectively. After 24 and 48 hours, the cell proliferation activity of each group was measured by cell counting kit-8 method, and the apoptosis rate of each group was detected by flow cytometry. Finally, Q-PCR was used to further reveal the effects of canine adipose-derived mesenchymal stem cell exosomes on PCNA, Bcl-2 and Bax genes in these cells. RESULTS AND CONCLUSION: Canine adipose-derived mesenchymal stem cells, their conditioned media, and exosomes could significantly promote proliferation and reduce apoptosis in damaged canine renal tubular epithelial cells (P < 0.05). Among them, canine adipose-derived mesenchymal stem cell exosomes worked best, which could significantly increase the expression of PCNA and Bcl-2 genes in damaged canine renal tubular epithelial cells (P < 0.05). These results suggest that canine adipose-derived mesenchymal stem cells can repair the canine renal tubular epithelial cell damage induced by gentamicin through their exosomes.

Blocking pannexin-1 alleviates cisplatin-induced acute kidney injury in mice by reducing renal inflammatory cell infiltration / 南方医科大学学报

OBJECTIVE@#To investigate the effect of blocking pannexin-1 against acute kidney injury induced by cisplatin.@*METHODS@#Twenty-six male C57BL/6 mice aged 6-8 weeks were randomly divided into control group, cisplatin model (Cis) group and cisplatin + carbenoxolone treatment group (Cis + CBX). In Cis group and Cis + CBX group, the mice were injected intraperitoneally with 20 mg/kg of cisplatin and with CBX (20 mg/kg) at 30 min before and 24 and 48 h after cisplatin inhjection, respectively. All the mice were sacrificed at 72 h after cisplatin injection, and plasma and kidney samples were collected for testing mRNA and protein expression levels of pannexin-1 in the renal tissue using RT-qPCR and Western blotting and for detecting plasma creatinine and BUN levels; the pathological changes in the renal tissues were observed using Periodic Acid-Schiff staining. The expression of kidney injury molecule 1 (KIM-1) was examined using immunohistochemistry and the mRNA expressions of KIM-1 and neutrophil gelatinase- related lipid transport protein (NGAL) were detected by RT-qPCR to evaluate the injuries of the renal tubules. The infiltration of F4/80-positive macrophages and CD4-positive T cells were observed by immunofluorescence. In the experiment, human proximal tubule epithelial cell line HK-2 was stimulated with 50 μmol/L cisplatin to establish a cell model of acute kidney injury, and the mRNA and protein expressions of pannexin-1 were detected by RT-qPCR and Western blotting at 4, 6, 12, 18 and 24 h after the stimulation.@*RESULTS@#Compared with the control mice, the cisplatin-treated mice showed significantly up-regulated protein levels ( < 0.05) and mRNA levels ( < 0.005) of pannexin-1 in the kidney tissue. Cisplatin stimulation also caused significant increases in the protein levels ( < 0.005) and mRNA levels ( < 0.005) of pannexin-1 in cultured HK-2 cells. Compared with cisplatin-treated mice, the mice treated with both cisplatin and the pannexin-1 inhibitor CBX showed obviously lessened kidney pathologies and milder renal tubular injuries with significantly reduced plasma BUN and Scr levels ( < 0.01), expressions of KIM-1 and NGAL in the kidney ( < 0.05), and infiltration of F4/80-positive macrophages ( < 0.01) and CD4- positive T cells ( < 0.05) in the kidney tissues.@*CONCLUSIONS@#In cisplatin induced acute kidney injury mice model, Pannexin-1 expression is up-regulated in the kidneys tissue, and blocking pannexin-1 alleviates the acute kidney injury reducing renal inflammatory cell infiltration.

Preventive effect of Shenkang injection against high glucose-induced senescence of renal tubular cells / 医学前沿

Shenkang injection (SKI) is a classic prescription composed of Radix Astragali, rhubarb, Astragalus, Safflower, and Salvia. This treatment was approved by the State Food and Drug Administration of China in 1999 for treatment of chronic kidney diseases based on good efficacy and safety. This study aimed to investigate the protective effect of SKI against high glucose (HG)-induced renal tubular cell senescence and its underlying mechanism. Primary renal proximal tubule epithelial cells were cultured in (1) control medium (control group), medium containing 5 mmol/L glucose; (2) mannitol medium (mannitol group), medium containing 5 mmol/L glucose, and 25 mmol/L mannitol; (3) HG medium (HG group) containing 30 mmol/L glucose; (4) SKI treatment at high (200 mg/L), medium (100 mg/L), or low (50 mg/L) concentration in HG medium (HG + SKI group); or (5) 200 mg/L SKI treatment in control medium (control + SKI group) for 72 h. HG-induced senescent cells showed the emergence of senescence associated heterochromatin foci, up-regulation of P16 and cyclin D1, increased senescence-associated β-galactosidase activity, and elevated expression of membrane decoy receptor 2. SKI treatment potently prevented these changes in a dose-independent manner. SKI treatment prevented HG-induced up-regulation of pro-senescence molecule mammalian target of rapamycin and p66Shc and down-regulation of anti-senescence molecules klotho, sirt1, and peroxisome proliferator-activated receptor-g in renal tubular epithelial cells. SKI may be a novel strategy for protecting against HG-induced renal tubular cell senescence in treatment of diabetic nephropathy.

Molecular mechanisms of mycelium of Cordyceps sinensis ameliorating renal tubular epithelial cells aging induced by D-galactose via inhibiting autophagy-related AMPK/ULK1 signaling activation / 中国中药杂志

To explore the effects and molecular mechanisms of mycelium of Cordyceps sinensis(MCs)improving renal tubular epithelial cells aging induced by D-galactose,the renal proximal tubular epithelial cells(NRK-52E cells)of rats in vitro were divided into the normal group(N),the D-gal model group(D),the low dose of MCs group(L-MCs),the medium dose of MCs group(M-MCs)and the high dose of MCs group(H-MCs),and treated by the different measures,respectively.More specifically,the NRK-52E cells in each group were separately treated by 1%fetal bovine serum(FBS)or D-galactose(D-gal,100 mmol·L~(-1))or D-gal(100 mmol·L~(-1))+MCs(20 mg·L~(-1))or D-gal(100 mmol·L~(-1))+MCs(40 mg·L~(-1))or D-gal(100 mmol·L~(-1))+MCs(80 mg·L~(-1)).After the intervention for24 h or 48 h,firstly,the effects of D-gal on the protein expression levels of klotho,P27 and P16,the staining of senescence-associatedβ-galactosidase(SA-β-gal)and the activation of adenosine monophosphate activated protein kinase(AMPK)/uncoordinated 51-like kinase 1(ULK1)signaling in the NRK-52E cells were detected,respectively.Secondly,the effects of MCs on the activation of the NRK-52E cells proliferation were investigated,respectively.Finally,the effects of MCs on the protein expression levels of klotho,P27,P16and microtubule-associated protein 1 light chain 3(LC3),the staining of SA-β-gal and the activation of AMPK/ULK1 signaling in the NRK-52E cells exposed to D-gal were examined severally.The results indicated that,for the NRK-52E cells,D-gal could cause aging,induce the protein over-expression levels of the phosphorylated AMPK(p-AMPK)and the phosphorylated ULK1(p-ULK1)and activate AMPK/ULK1 signaling pathway.The co-treatment of MCs at the medium and high doses and D-gal could significantly ameliorate the protein expression levels of klotho,P27,P16 and the staining of SA-β-gal,suggesting the anti-cell aging actions.In addition,the cotreatment of MCs at the medium and high doses and D-gal could obviously improve the protein expression levels of LC3,p-AMPK,and p-ULK1,inhibit the activation of AMPK/ULK1 signaling and increase autophagy.On the whole,for the renal tubular epithelial cells aging models induced by D-gal,MCs not only has the in vitro actions of anti-aging,but also intervenes aging process by inhibiting autophagy-related AMPK/ULK1 signaling activation,which may be the novel molecular mechanisms of MCs protecting against aging of the renal tubular epithelial cells.

MiRNA-148b targeted AMPKα1 mediates high glucose-induced apoptosis in human renal tubular epithelial cells via oxidative stress / 中华肾脏病杂志

Objective To investigate the expression and mechanism of microRNA-148b (miRNA-148b) in high glucose-induced renal tubular injury.Method HK-2 cells cultured in vitro were divided into normal glucose group,mannitol hypertonic control group and high glucose group.After 48 hours of culture,the expression of miRNA-148b was detected by real-time quantitative PCR.2',7'-Dichlorodihydrofluorescein diacetate (DCFH-DA) was used for detecting production of ROS and observed under fluorescence microscope for analysis;The expression of AMPKot1,Bcl-2,NOX2,NOX4,activated caspase3 (cleaved-caspase3) were detected by Western blotting.Results Compared with the normal glucose group,the expression of miRNA-148b was up-regulated in HK-2 cells in high glucose group and hypertonic group (P ＜ 0.01),and the production of ROS increased (P ＜ 0.01).The expression of NOX2 and NOX4 was increased,AMPKα1 and Bcl-2 decreased,and cleaved caspase-3 was increased (all P ＜ 0.01).Conclusions HG up-regulated miRNA-148b expression and down-regulated its target gene AMPKα1 which promotes the expression of NOX2 and NOX4 in HK-2 cells.MiRNA-148b promotes apoptosis of HK-2 cells via increasing production of ROS and enhancing cleaved-caspase3 for Bcl-2 insufficiency.The tubular toxicity of high glucose is partly due to osmotic pressure.MiRNA-148b may be involved in the pathological injury of diabetic nephropathy and is expected to become a new therapeutic target for diabetic nephropathy.

Effect and mechanism of atorvastatin on cellular inflammatory response induced by calcium oxalate crystals / 中华泌尿外科杂志

Objective@#To investigate the effect and mechanism of atorvastatin (ATV) on the inflammatory response of human renal tubular epithelial cells (HK-2 cells) induced by calcium oxalate crystals.@*Methods@#HK-2 cells were divided into control group (normal medium), ATV group (after 3 h pretreatment with 40 μmol/L ATV, replaced with normal medium), calcium oxalate crystal stimulation group (4 mmol/L calcium oxalate crystal) and ATV treatment group (after 3 h pretreatment with 40 μmol/L ATV, replaced with 4 mmol/L calcium oxalate crystals). After 12 h, the cells were collected, and the expression levels of NLRP3 and Cleaved caspase-1 were detected by immunohistochemical staining and Western blotting. The expression level of NF-κB was detected by immunofluorescence and Western blotting. The cell culture supernatant was collected to detecte the concentrations of interleukin-1β (IL-1β) and interleukin-18 (IL-18) by enzyme linked immunosorbent assay (ELISA).@*Results@#Western blot analysis showed that the relative expression of NLRP3 (0.125±0.013 vs. 0.135±0.007) and Cleaved caspase-1 (0.090±0.014 vs. 0.095±0.006) was decreased in the ATV group compared with the control group, but the difference was not statistically significant (P>0.05). The relative expression of NLRP3 (0.315±0.021 vs. 0.135±0.007, P<0.001) and Cleaved caspase-1 (0.235±0.008 vs. 0.095±0.006, P<0.001) was significantly increased in the calcium oxalate crystal stimulation group compared with the control group. While the relative expression of NLRP3 (0.245±0.007 vs. 0.315±0.021, P<0.05) and Cleaved caspase-1 (0.170±0.017 vs. 0.235±0.008, P<0.05) in the ATV treatment group was significantly lower than that in the calcium oxalate crystal stimulation group. The results of immunohistochemical staining showed that the expression trends of NLRP3 and Cleaved caspase-1 in each group were consistent with those obtained by Western blotting. The ELISA results showed that the concentration of inflammatory factors IL-1β [(162.00±21.21)pg/ml vs. (183.50±7.78) pg/ml, P>0.05] and IL-18 [(176.50±24.12)pg/ml vs.(182.50±20.51)pg/ml, P>0.05] in the ATV group was lower than that in the control group, but the difference were not statistically significant (P>0.05). The concentrations of IL-1β[(850.50±48.79)pg/ml vs. (183.50±7.78)pg/ml, P<0.001] and IL-18 [(526.00±39.61)pg/ml vs. (182.50±20.51)pg/ml, P<0.001] were significantly increased in the cell culture medium of the calcium oxalate crystal stimulation group compared with the control group, while the concentrations of IL-1β [(452.50±36.06)pg/ml vs. (850.50±48.79) pg/ml, P<0.01] and IL-18 [(403.50±23.33)pg/ml vs. (526.00±39.61)pg/ml, P<0.05] was significantly reduced in the cell culture medium of the ATV treatment group compared with the calcium oxalate crystal stimulation group. Western blot analysis showed that the relative expression of NF-κB (0.105±0.021 vs. 0.100±0.014) in the ATV group was decreased compared with the control group, but the difference was not statistically significant (P>0.05). The relative expression of NF-κB (0.295±0.035 vs. 0.100±0.014, P<0.001) in the calcium oxalate crystal stimulation group was significantly increased compared with the control group. While the relative expression of NF-κB (0.160±0.012 vs. 0.295±0.035, P<0.05) in the ATV treatment group was significantly lower than that in the calcium oxalate crystal stimulation group. The expression of NF-κB by immunofluorescence staining was consistent with the results of Western blotting.@*Conclusions@#Calcium oxalate crystals can induce the inflammatory response of HK-2 cells, while ATV can exert anti-inflammatory effects by inhibiting the activation of NLRP3 inflammasome and decreasing the secretion of inflammatory factors IL-1β, IL-18 and the expression of NF-κB.

Effect and mechanism of atorvastatin on cellular inflammatory response induced by calcium oxalate crystals / 中华泌尿外科杂志

Objective To investigate the effect and mechanism of atorvastatin (ATV) on the inflammatory response of human renal tubular epithelial cells (HK-2 cells) induced by calcium oxalate crystals.Methods HK-2 cells were divided into control group (normal medium),ATV group (after 3 h pretreatment with 40 μmol/L ATV,replaced with normal medium),calcium oxalate crystal stimulation group (4 mmol/L calcium oxalate crystal) and ATV treatment group (after 3 h pretreatment with 40 μmol/L ATV,replaced with 4 mmol/L calcium oxalate crystals).After 12 h,the cells were collected,and the expression levels of NLRP3 and Cleaved caspase-1 were detected by immunohistochemical staining and Western blotting.The expression level of NF-κB was detected by immunofluorescence and Western blotting.The cell culture supernatant was collected to detecte the concentrations of interleukin-1 β (IL-1β) and intedeukin-18 (IL-18) by enzyme linked immunosorbent assay (ELISA).Results Western blot analysis showed that the relative expression of NLRP3 (0.125 ±0.013 vs.0.135 ±0.007) and Cleaved caspase-1 (0.090 ±0.014 vs.0.095±0.006) was decreased in the ATV group compared with the control group,but the difference was not statistically significant (P ＞ 0.05).The relative expression of NLRP3 (0.315 ±0.021 vs.0.135 ± 0.007,P ＜ 0.001) and Cleaved caspase-1 (0.235 ± 0.008 vs.0.095 ± 0.006,P ＜0.001) was significantly increased in the calcium oxalate crystal stimulation group compared with the control group.While the relative expression of NLRP3 (0.245 ±0.007 vs.0.315 ±0.021,P ＜0.05) and Cleaved caspase-1 (0.170 ±0.017 vs.0.235 ±0.008,P ＜0.05) in the ATV treatment group was significantly lower than that in the calcium oxalate crystal stimulation group.The results of immunohistochemical staining showed that the expression trends of NLRP3 and Cleaved caspase-1 in each group were consistent with those obtained by Western blotting.The ELISA results showed that the concentration of inflammatory factors IL-1 β [(162.00±21.21)pg/ml vs.(183.50±7.78) pg/ml,P＞0.05] and IL-18 [(176.50±24.12)pg/ml vs.(182.50 ± 20.51) pg/ml,P ＞ 0.05] in the ATV group was lower than that in the control group,but the difference were not statistically significant (P ＞ 0.05).The concentrations of IL-1β [(850.50 ± 48.79)pg/ml vs.(183.50 ± 7.78) pg/ml,P ＜ 0.001] and IL-18 [(526.00 ± 39.61) pg/ml vs.(182.50 ±20.51)pg/ml,P ＜0.001] were significantly increased in the cell culture medium of the calcium oxalate crystal stimulation group compared with the control group,while the concentrations of IL-1 β [(452.50 ±36.06)pg/ml vs.(850.50±48.79) pg/ml,P＜0.01] and IL-18 [(403.50 ±23.33)pg/ml vs.(526.00 ±39.61)pg/ml,P ＜0.05] was significantly reduced in the cell culture medium of the ATV treatment group compared with the calcium oxalate crystal stimulation group.Western blot analysis showed that the relative expression of NF-κB (0.105 ±0.021 vs.0.100 ±0.014) in the ATV group was decreased compared with the control group,but the difference was not statistically significant (P ＞ 0.05).The relative expression of NF-κB (0.295 ±0.035 vs.0.100 ±0.014,P ＜0.001) in the calcium oxalate crystal stimulation group was significantly increased compared with the control group.While the relative expression of NF-κB (0.160 ± 0.012 vs.0.295 ± 0.035,P ＜ 0.05) in the ATV treatment group was significantly lower than that in the calcium oxalate crystal stimulation group.The expression of NF-κB by immunofluorescence staining was consistent with the results of Western blotting.Conclusions Calcium oxalate crystals can induce the inflammatory response of HK-2 cells,while ATV can exert anti-inflammatory effects by inhibiting the activation of NLRP3 inflammasome and decreasing the secretion of inflammatory factors IL-1β,IL-18 and the expression of NF-κB.

Effect of netrin-1 on high glucose induced injury of renal tubular epithelial cells / 中国病理生理杂志

AIM:To study the effect of netrin-1 on the damage of renal tubular epithelial cells induced by high glucose.METHODS:Human renal tubular epithelial HK-2 cells were treated with high glucose.Real-time PCR and Western blot were used to detect the expression level of netrin-1 in the cells.HK-2 cells were infected with netrin-1-overexpressing lentivirus, and the effect of netrin-1 over-expression on the HK-2 cells treated with high glucose was observed.The apoptosis rate was analyzed by flow cytometry.The protein level of cleaved caspase-3 was determined by Western blot.lactate dehydrogenase (LDH) activity in the culture medium was measured by 2, 4-binitrobenzene hydrazine method.The content of malondialdehyde (MDA) in the culture medium was detected by thiobarbituric acid method.The concentrations of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the culture medium were measured by ELISA.RE-SULTS:The expression of netrin-1 at mRNA and protein levels in the HK-2 cells after high glucose treatment was significantly lower than that in the control cells (P<0.05).Infection with netrin-1-over-expressing lentivirus up-regulated the expression of netrin-1 in the HK-2 cells treated with high glucose.High glucose promoted the secretion of IL-1βand TNF-α, decreased the levels of LDH and MDA in the cell culture supernatant, and induced apoptosis and activation of caspase-3 in renal tubular epithelial cells (P<0.05).After the HK-2 cells with up-regulation of netrin-1 were induced by high glucose, the IL-1βand TNF-αsecretion, the levels of LDH and MDA in the culture medium, the apoptosis, and the level of activated caspase-3 protein in the cells were all decreased, as compared with the control cells (P<0.05).CONCLU-SION:Up-regulation of netrin-1 expression attenuates oxidative damage and inflammatory injury, and reduces apoptosis induced by high glucose in renal tubular epithelial cells.

Protective Effect and Mechanism of Aqueous Extract of Perillae Folium on Adriamycin-induced Oxidative Injury in HK-2 Cell / 中国实验方剂学杂志

Objective: To investigate the protective effect of Perillae Folium with aqueous extract (PFAE) on some key factors of Adriamycin (ADR)-induced oxidative injury in human renal tubular epithelial cells(HK-2), including the survival rate, oxidative injury indexes and cell apoptosis,in order to define the underlying mechanism. Method: A model of ADR-induced HK-2 cells oxidative injury was established in vitro, then cell viability was detected by cell counting kit-8 (CCK-8) after intervention with positive reference N-acetylcysteine (NAC) or PFAE (5,15,45 g·L-1) at different concentrations. According to the morphological changes under microscopy, the optimum concentration of PFAE was screened out for the follow-up experiments. Then, the experiments were divided into six groups:blank group, ADR (0.05 g·L-1) group, PFAE (15 g·L-1) group, ADR+PFAE (0.05+15) g·L-1 group, NAC (0.81 g·L-1) group, and ADR+NAC (0.05+81) g·L-1 group. After that, malondialdehyde (MDA), superoxide dismutase (SOD), total antioxidant capacity(TAC) were measured in the cell homogenate after 24 h administration. The level of reactive oxygen species (ROS) was detected by 2',7'-dichloroflurescin diacetate (DCFH-DA) fluorescence probe. Flow cytometry and TdT-mediated dUTP Nick-End Labeling (TUNEL) were used to monitor the cell apoptosis. Western blot was used to observed the expressions of mitochondrial apoptosis-associated proteins, like B lymphocyte tumor-2 gene (Bcl-2), Bcl-2 related X protein (Bax), cysteine aspartate protease-9 (Caspase-9), cysteine aspartate protease-3 (Caspase-3) and poly ADP-ribose polymerase (PARP), as well as their shear bodies. In addition, the phosphorylation protein expressions of p38 mitogen-activated protein kinase (p38 MAPK), extracellular signal-regulated kinase (ERK), c-Jun amino-terminal kinase (JNK) in mitogen-activated protein kinase (MAPK) signaling transduction pathway were detected by Western blot. Result: Compared with blank group, ADR group showed a decreased cell viability (PPPPPPPP-1. The ATC and SOD levels were increased in ADR+PFAE group and ADR+NAC group (PPConclusion: PFAE could alleviate the oxidative injury of HK-2 cells induced by ADR, and have an antioxidant effect, which inhibited cell apoptosis through mitochondrial apoptotic pathway and ERK/p38 MAPK signaling pathway.

Effect of Tongfengning Serum Containing on Expression of Urate Transporter in HK-2 Induced by Uric Acid / 中国实验方剂学杂志

Objective: Study on the mechanism of Tongfengning in reducing serum uric acid from the perspective of renal urate transporter. Method: The human renal tubular epithelial cells(HK-2)was randomly divided into normal group, model group, Tongfengning low, medium and high dose group (7.65,15.3,30.6 g·kg-1) and benzbromarone group (50 μmo1·L-1),different culture media were given for intervention.HK-2 and cell supernatant were collected after 24 h of intervention. The expressions of urate transporter 1 (URAT1), glucose transporter 9 (GLUT9), organic anion transporter 1(OAT1), organic anion transporter 3(OAT3), and ATP-binding cassette superfamily G member 2 (ABCG2) protein and mRNA were detected in HK-2 of all groups by Western blot and Real-time PCR. Result: Compared with normal group, the expression of URAT1, GLUT9 protein and mRNA was significantly increased(PPPPPConclusion: Tongfengning can regulate the reabsorption and secretion of uric acid in renal tubules, promote the excretion of uric acid in kidney and reduce the level of serum uric acid by down-regulating the expression of URAT1, GLUT9 protein and mRNA in HK-2 and up-regulating the expression of ABCG2 protein and mRNA. It is suggested that the regulation of renal uric acid transporter protein may be one of the specific mechanisms of Tongfengning to reduce serum uric acid by promoting dampness and turbid removal. OAT1, OAT3 protein and mRNA were not expressed in HK-2 cultured in vitro.

Effect of a novel PPARγ partial agonist CMHX008 on hyperglycemia-induced fibrogenesis in renal tubular epithelial HK-2 cells and its mechanism / 中国药理学通报

Aim To investigate the effect of CMHX008, a novel peroxisome proliferator-activated receptor γ (PPARγ) partial agonist, on fibrogenic pathways and its potential mechanism in renal tubular epithelial HK-2 cells in comparison with rosiglitazone. Methods HK-2 cells were cultured with 30 mmol . L 1 D-(+)-glucose, and then treated with rosiglitazone and CMHX008. Cell counting kit-8(CCK-8) was used to detect cell viability; immunoblotting was used to detect protein expression fibrogenic markers and p-PPARγ(ser273) in HK-2 cells; quantitative real time PCR (qRT-PCR) was used to detect fibrosis-related mRNA levels; wound healing assay and transwell assay were used to detect the migration and invasion ability of HK-2 cells. Results CCK-8 analysis showed that 3 (imol . L 1 rosiglitazone and 3 μmol . L 1 CMHX008 had no obvious cytotoxicity to HK-2 cells; immunoblotting revealed that rosiglitazone and CMHX008 could reverse the up-regulation of p-PPARγ(ser273), reduce transforming growth factor β1 (TGF-β1) and α-smooth muscle actin(α-SMA) protein levels, and up-regulate E-cadherin protein expression levels in HK-2 cells in high glucose conditions; wound healing assay and transwell assay showed that rosiglitazone and CMHX008 could inhibit the increase of migration and invasion ability of hyperglycemia-cultured HK-2 cells. Conclusions The novel PPAR7 agonist CMHX008 can improve hyperglycemia-induced renal tubular fibrosis, which may be possibly related to the inhibition of p-PPARγ(Ser273) phosphorylation.

Effect of overexpression of retinoic acid receptor α on epithelial -to -mesenchymal transition induced by hypoxia in renal tubular epithelial cells / 中华实用儿科临床杂志

Objective To explore the effect of overexpression of retinoic acid receptor α(RARα)on epithelial-to-mesenchymal transition(EMT)induced by hypoxia in renal tubular epithelial cells(NRK-52E).Methods The RARα lentivirus vector and negative control lentivirus vector were synthetised.The NRK-52E cells were divided into 4 groups:the normal control group,the hypoxia model group,the transfection group and the negative control group.Puro-mycin(2 mg/L)was added in transfection group and negative control group for screening after gene interference for 72 h.Then the 2 groups were subjected to hypoxia/reoxygenation,but the normal control group had no treatment. The change of cellular morphology was observed by using light microscope;the mRNA and protein expressions of RARα, E-cadherin,α -smooth muscle actin(α-SMA)in NRK-52E cells were detected by adopting reverse transcription-polymerase chain reaction(RT-PCR)and Western blot after hypoxia for 48 h.Results (1)Light microscope re-vealed that cells in both hypoxia model group and negative control group cells became atrophic and elongated,which were consistent with the morphology of myofibroblasts.But cells in transfection group cells were cubic,forming an epi-thelial monolayer.(2)Compared with the normal control group,the mRNA and protein expressions of RARα and E-cadherin in hypoxia model group were dramatically reduced(mRNA:0.58 ± 0.12 vs.1.00 ± 0.00,0.11 ± 0.00 vs. 1.00 ± 0.00,t= -0.63,767.30,all P<0.05;protein:0.63 ± 0.12 vs.1.62 ± 0.16,0.44 ± 0.22 vs.1.27 ± 0.08,t=8.61,6.19,all P<0.05),but the mRNA and protein expressions of α-SMA were higher(3.47 ± 0.83 vs.1.00 ± 0.00,1.39 ± 0.16 vs.0.64 ± 0.10,t= -5.01,-6.91,all P<0.05).(3)The mRNA and protein expressions of RARα and E-cadherin in the transfection group were significantly increased,compared with hypoxia model group(mRNA:4.69 ± 1.34 vs.0.58 ± 0.12,0.23 ± 0.00 vs.0.11 ± 0.00,q=9.13,25.48,all P<0.05;protein:1.39 ± 0.19 vs. 0.63 ± 0.12,0.87 ± 0.09 vs.0.44 ± 0.22,q=7.92,4.30,all P<0.05)and negative control group(mRNA:4.69 ± 1.34 vs.0.55 ± 0.21,0.23 ± 0.00 vs.0.12 ± 0.01,q=9.20,23.35,all P<0.05;protein:1.39 ± 0.19 vs.0.65 ±0.18,0.87 ± 0.09 vs.0.39 ± 0.21,q=7.71,4.80,all P<0.05).Conversely,the mRNA and protein levels of α-SMA were obviously lower in transfection group(1.52 ± 0.34 vs.3.47 ± 0.83,4.05 ± 0.81,0.82 ± 0.13 vs.1.39 ± 0.10,1.17 ± 0.10,q=4.88,6.33,7.50,4.61,all P<0.05).The difference in mRNA and protein expressions of RARα,E-cadherin,α-SMA between the hypoxia group and the negative control group had no statistical significance (all P>0.05).Conclusion Overexpression of RARα could alleviate EMT of renal tubular epithelial cells induced by hypoxia.