Animals ; Epithelial Cells ; cytology ; drug effects ; Humans ; Kidney Tubules ; cytology ; drug effects ; Oleanolic Acid ; analogs & derivatives ; pharmacology ; Podocytes ; drug effects

Phospholipase D (PLD) is an enzyme involved in signal transduction and widely distributed in mammalian cells. The signal transduction pathways and role for phospholipid metabolism during hormonal response in cortical collecting duct remain partly undefined. It has been reported that dexamethasone increases transepithelial transport in M-1 cells that are derived from the mouse cortical collecting duct. We investigated the expression and activity of PLD in M-1 cells. Basal PLD activity of M-1 cells cultured in the presence of dexamethasone (5 microM) was higher than in the absence of dexamethasone. Dexamethasone and ATP activated PLD in M-1 cells but phorbol ester did not stimulate PLD activity. Vasopressin, bradykinin, dibutyryl cyclic AMP, and ionomycin were ineffective in activating PLD of the cells. The PLD2 isotype was detected by immunoprecipitation but PLD1 was not detected in M-1 cells. Addition of GTPgammaS and ADP-ribosylation factor or phosphatidylinositiol 4,5-bisphosphate to digitonin-permeabilized cells did not augment PLD activity. In intact cells PLD activity was increased by sodium oleate but there was no significant change between dexamethasone treated- and untreated cells by oleate. These results suggest that at least two types of PLD are present in M-1 cells and PLD plays a role in the corticosteroid-mediated response of cortical collecting duct cells.
Animal ; Biological Transport/drug effects ; Dexamethasone/pharmacology* ; Dose-Response Relationship, Drug ; Drug Interactions ; Glycerophospholipids/analysis ; Isoenzymes/drug effects ; Kidney Cortex/cytology ; Kidney Tubules, Collecting/drug effects* ; Kidney Tubules, Collecting/cytology ; Mice ; Mice, Transgenic ; Oleic Acid/pharmacology ; Phospholipase D/drug effects*

In kidney, the role of cell proliferation, differentiation, apoptosis, inflammatory mediators and cytokines expression is closely related with cell signaling pathways, including tyrosine kinase pathway, transforming growth factor-beta/Smad pathway, Rho/Rho-associated coiled-coil forming protein kinase pathway, phosphoinositol pathway, cyclic nucleotide pathway, nuclear factor kappaB pathway and so on. Some Chinese herbs and their extracts, such as rhubarb and triptolide, as well as some Chinese herbal prescriptions, such as astragalus-angelica mixture and Chailing decoction, not only could ameliorate proliferation, differentiation and apoptosis of renal cell by regulating cell signaling pathways, but also could control target gene transcription, expression and its biological effects through inhibiting the phosphorylation of key signaling molecules.
Animals ; Apoptosis ; drug effects ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Kidney ; cytology ; drug effects ; metabolism ; Signal Transduction ; drug effects

Calcium Channel Blockers ; pharmacology ; Cell Survival ; drug effects ; Drug Antagonism ; Humans ; Kidney ; cytology ; drug effects ; Lead ; toxicity

OBJECTIVETo explore the toxic effects of lead acetate on the apoptosis and ultrastructure of human renal tubular epithelial cells (HK-2).

METHODSAfter HK-2 cells were exposed to 5, 10 and 20 µmol/L lead acetate for 24 h, the morphological changes of HK-2 cells were observed by Hochest 33342-PI staining, and the ultrastructure changes of HK-2 cells were examined under a electron microscope, LDH activity and MDA content in supernatant of HK-2 cellular culture were detected by spectrophotometer, DNA damage of HK-2 was determined by DNA ladder and the apoptotic rates of HK-2 cells were measured by flow cytometry.

RESULTSThe morphological changes of apoptotic HK-2 cells in exposure group were observed by Hochest 33342-PI staining. The cytoplasm vacuoles, karyopycnosis, nuclear membrane vague and apoptotic bodies in HK-2 cells of exposure group were found under electron microscopy. LDH activity and MDA contents in exposure group increased significantly, as compared to control group (P < 0.01). The results of DNA Ladder showed that DNA damage of HK-2 cells in exposure group appeared. The apoptotic rates of HK-2 cells exposed to 5, 10, 20 µmol/L lead acetate were 14.16% ± 2.94%, 19.45% ± 2.73%, 25.01% ± 3.97%, respectively, which were significantly higher than that (5.81% ± 2.18%) in control group (P < 0.05).

CONCLUSIONLead acetate could remarkably induce the apoptosis of HK-2 cells and affect the kidney.

Apoptosis ; drug effects ; Cell Line ; Epithelial Cells ; cytology ; drug effects ; ultrastructure ; Humans ; Kidney Tubules, Proximal ; cytology ; drug effects ; ultrastructure ; Organometallic Compounds ; toxicity

OBJECTIVETo explore the effect of resveratrol on transforming growth factor-beta1 (TGF-beta1) induced transdifferentiation of podocytes.

METHODSMouse podocytes in vitro cultured under differentiating conditions for 10 days were divided into the normal group, the model group, the high dose resveratrol group, and the low dose resveratrol group. The podocytes in the high and low dose resveratrol groups were intervened with 5 micromol/L and 2 micromol/L resveratrol respectively for 30 min. Those in the model group and the two resveratrol treated groups were continually incubated with 5 ng/mL TGF-beta1 for 72 h. Those in the normal group were routinely cultured. The protein expression of podocyte phenotypic protein molecules such as E-cadherin, P-cadherin, zonula occludens-1 (ZO-1), NEPH1, and alpha-smooth muscle-actin (alpha-SMA) were detected by immunocytochemistry, flow cytometry (FCM), and Western blot. A simple albumin influx assay was used to evaluate the filtration barrier function of podocyte monolayer.

RESULTSCompared with the normal control group, E-cadherin (+) percentage rate, the protein expression of P-cadherin, ZO-1, and NEPH1 significantly decreased in the model group (P < 0.05), but the expression of alpha-SMA and albumin permeability across podocyte monolayers increased significantly (P < 0.05). Compared with the model group, E-cadherin (+) percentage rate significantly increased (P < 0.05) and albumin permeability across podocyte monolayers decreased significantly (P < 0.05) in the high and low dose resveratrol groups. In the low dose resveratrol group, the expression of P-cadherin and NEPH1 significantly increased (P < 0.05). In the high dose resveratrol group, the expression of P-cadherin, ZO-1, and NEPH1 increased significantly, and the expression of alpha-SMA decreased significantly (P < 0.05). The correlations between resveratrol concentrations and the expression of E-cadherin (+), P-cadherin, and NEPH1 were significantly positive (r(E-cadherin (+)) = 0.772, r(P-cadherin) = 0.756, r(NEPH1) = 0.809, P < 0.05).

CONCLUSIONThe role of resveratrol in inhibiting TGF-beta1 induced phenotype abnormality might be an important mechanism for preserving the integrality of glomerular filtration barrier and decreasing proteinuria.

Animals ; Cell Transdifferentiation ; drug effects ; Cells, Cultured ; Kidney Tubules ; cytology ; drug effects ; Mice ; Podocytes ; cytology ; drug effects ; Stilbenes ; pharmacology ; Transforming Growth Factor beta1 ; metabolism

Epithelial to mesenchymal transition (EMT) has been proposed as a key role leading to the progressive tubulo-interstitial fibrosis (TIF). The tubular EMT is an highly regulated process involving four key steps including: loss of epithelial cell adhesion, de novo smooth muscle actin expression and actin reorganization, disruption of tubular basement membrane,and enhanced cell migration and invasion. These crucial processes are closely connected to the relative actions on many signaling pathways in EMT. Additionally, increasing evidences suggest that some Chinese herbal medicines and their extracts, such as Astragali Radix, Cordyceps, Salvia miltiorrhiza, as well as Chinese. herbal prescriptions including Astragalus Angelica mixture and Supplementing Qi and activating blood circulation decoction, could intervene the related events controlling EMT both in vitro and in vivo. Chinese herbal medicines could ameliorate TIF by intervening the course of EMT.
Animals ; Drugs, Chinese Herbal ; pharmacology ; Epithelial-Mesenchymal Transition ; drug effects ; Gene Expression Regulation ; drug effects ; Humans ; Kidney Tubules ; cytology ; drug effects ; metabolism ; Signal Transduction ; drug effects

OBJECTIVETo compare the serum miR-663 levels in renal transplant patients with and without acute rejection (AR) and explore the role of miR-663 acute renal graft rejection.

METHODSReal time-PCR was used to determine serum miR-663 levels in renal transplant recipients with and without AR. MTT assay and Annexin V-FITC assay were employed to examine the viability and apoptosis of human renal glomerular endothelial cells (HRGEC) treated with a miR-663 mimic or a miR-663 inhibitor, and ELISA was performed to detect the expression of inflammation-related cytokines including IL-6, IFN-γ, CCL-2 and TNF-α in the cells. Transwell assay was used to examine the effect of miR-663 mimic and miR-663 inhibitor on the chemotactic capability of macrophages.

RESULTSSerum miR-663 level was significantly higher in renal transplant recipients with AR than in those without AR. The miR-663 mimic significantly inhibited the viability of HRGECs and increase the cell apoptosis rate, while miR-663 inhibitor suppressed the cell apoptosis. The miR-663 mimic increased the expression levels of inflammation-related cytokines and enhanced the chemotactic capability of macrophages.

CONCLUSIONmiR-663 might play important roles in acute renal graft rejection and may become a therapeutic target for treating AR.

Apoptosis ; Cells, Cultured ; Cytokines ; metabolism ; Endothelial Cells ; cytology ; Graft Rejection ; blood ; Humans ; Kidney Glomerulus ; cytology ; Kidney Transplantation ; Macrophages ; cytology ; drug effects ; MicroRNAs ; blood

OBJECTIVETo observe the expressions of Wnt/beta-catenin and the effects of tanshinone IIA (TII A) on Wnt/beta-catenin signaling pathway in high glucose induced renal tubular epithelial cell transdifferentiation.

METHODSHuman kidney proximal tubular epithelial cells (HK-2) were divided into three groups, i. e., the normal glucose group, the high glucose group, and the high glucose plus tanshinone IIA group. The expression of beta-catenin was observed using immunocytochemical staining. The protein expression of beta-catenin, E-cadherin, and alpha-smooth muscle actin (alpha-SMA) were detected by Western blot. The mRNA levels of beta-catenin and E-cadherin were detected by RT-PCR.

RESULTSCompared with the normal glucose group, both the protein and the mRNA expressions of beta-catenin were significantly enhanced (P < 0.01), the expression of E-cadherin significantly decreased (P < 0.01), the expression of beta-catenin increased in the cytoplasm and nucleus in the high glucose group. TIIA at the final concentration of 100 micromol/L significantly reduced the ectopic expression of beta-catenin. At that concentration, the protein and mRNA expressions of beta-catenin in the nucleus significantly decreased, while the protein and mRNA expressions of E-cadherin were up-regulated. Meanwhile, the expression of alpha-SMA obviously decreased.

CONCLUSIONSWnt/beta-catenin signaling pathway participated in the high glucose induced renal tubular epithelial cell transdifferentiation. TIIA inhibited the transdifferentiation process possibly through down-regulating the activities of Wnt/beta-catenin signaling pathway, thus further playing a role in renal protection.

Cadherins ; metabolism ; Cell Line ; Cell Transdifferentiation ; drug effects ; Diterpenes, Abietane ; pharmacology ; Epithelial Cells ; cytology ; drug effects ; metabolism ; Glucose ; adverse effects ; Humans ; Kidney Tubules, Proximal ; cytology ; drug effects ; metabolism ; Wnt Signaling Pathway ; drug effects ; beta Catenin ; metabolism

OBJECTIVETo study effects of Yishen Kangxian Compound (YKC) and benazepril containing serums on HK-2 cells (human renal proximal tubule epithelial cells) in the process of renal tubular epithelial cells to mesenchymal myofibroblasts transdifferentiation (TEMT) by gene chip.

METHODSYKC and benazepril containing serums were prepared. Their inhibitory effects on HK-2 cells in the transforming growth factor-beta1 (TGF-beta1)-induced TEMT process were observed. HK-2 cells were randomly divided into four groups, i.e., the blank control group, the model group, the benazepril group, and the YKC group. The gross RNAs were extracted and purified by taking advantage of the HumanHT-12 v4 of IlluminaBeadChip. Differentially expressed genes were obtained after they were reversely transcribed to cDNA, incorporating biotin labeling probe, hybridized with GeneChip, picture signals of fluorescence in gene array scanned and compared with differential genes by computer analysis.

RESULTSDifferentially expressed genes were successfully identified by gene chip. Compared with the model group, there were 227 differentially expressed genes in the benazepril group, including 118 up-regulated genes and 109 downregulated genes. Compared with the model group, there were 97 differentially expressed genes in the YKC group, including 69 up-regulated genes and 28 down-regulated genes. The Gene Ontology (GO) analysis indicated that YKC was more actively involved in the regulatory process than benazepril in terms of cell damage, apoptosis, growth, NF-KB, protein kinase, neuron, and blood vessel growth.

CONCLUSIONSYKC and benazepril could inhibit the TEMT process of HK-2 cells. But YKC also had taken part in cell damage, apoptosis, growth,and more pathways of early stage TEMT.

Cell Line ; Cell Transdifferentiation ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Epithelial Cells ; cytology ; drug effects ; Genomics ; Humans ; Kidney Tubules, Proximal ; cytology ; pathology