cyclin-d1 and Kidney-Diseases

Podocytes are terminally differentiated cells with little proliferative capacity. The high expression levels of cell cycle inhibitory proteins, including p21, p27, and p57, play an important role in maintaining the low level of proliferation of mature podocytes. In the present study, we aimed to explore the role of yes-associated protein (YAP) signalling in adriamycin-induced podocyte re-entry into the cell cycle and dedifferentiation. Proliferating cell nuclear antigen (PCNA)-, cyclin-dependent kinase 4 (CDK4)-, and Cyclin D1-positive podocytes were found in mice with adriamycin-induced nephropathy. In vitro, adriamycin administration increased the percentage of cells in S phase and the upregulation of mesenchymal-related marker proteins. CDK4 and cyclin D1 were significantly up-regulated after incubation with adriamycin. Overexpression of YAP in podocytes promoted their entry into the cell cycle; up-regulated cyclin D1, desmin, and snail2 expression and down-regulated Wilms' tumour 1 (WT1) and nephrin production. Recombinant murine FGF-basic induced podocytes to re-enter the cell cycle, inhibited WT1 and nephrin, and increased desmin and snail2 expression. Pretreating podocytes with verteporfin, an inhibitor of YAP/ TEA domain transcription factor (TEAD), decreased the adriamycin-induced overexpression of cyclin D1 and reduced the ratio of S-phase podocytes. This result was further verified by knocking down YAP expression using RNA interference. In conclusion, adriamycin induced podocytes to re-enter the cell cycle via upregulation of CDK4 and cyclin D1 expression, which was at least partly mediated by YAP signalling. Re-entry into the cell cycle induced the over-expression of mesenchymal markers in podocytes.

Topics: Adaptor Proteins, Signal Transducing; Animals; Cell Cycle; Cell Cycle Proteins; Cell Dedifferentiation; Cyclin D1; Cyclin-Dependent Kinase 4; Desmin; Down-Regulation; Doxorubicin; Fibroblast Growth Factor 2; Kidney; Kidney Diseases; Male; Mice, Inbred BALB C; Podocytes; Signal Transduction; Snail Family Transcription Factors; Up-Regulation; YAP-Signaling Proteins

The mechanism of hypertension-induced renal fibrosis is not well understood, although it is established that high levels of angiotensin II contribute to the effect. Since β-catenin signal transduction participates in fibrotic processes, we evaluated the contribution of β-catenin-dependent signaling pathway in hypertension-induced renal fibrosis. Two-kidney one-clip (2K1C) hypertensive rats were treated with lisinopril (10 mg/kg/day for four weeks) or with pyrvinium pamoate (Wnt signaling inhibitor, single dose of 60 ug/kg, every 3 days for 2 weeks). The treatment with lisinopril reduced the systolic blood pressure from 220 ± 4 in 2K1C rats to 112 ± 5 mmHg (P < 0.05), whereas the reduction in blood pressure with pyrvinium pamoate was not significant (212 ± 6 in 2K1C rats to 170 ± 3 mmHg, P > 0.05). The levels of collagen types I and III, osteopontin, and fibronectin decreased in the unclipped kidney in both treatments compared with 2K1C rats. The expressions of β-catenin, p-Ser9-GSK-3beta, and the β-catenin target genes cyclin D1, c-myc, and bcl-2 significantly decreased in unclipped kidney in both treatments (P < 0.05). In this study we provided evidence that β-catenin-dependent signaling pathway participates in the renal fibrosis induced in 2K1C rats.

Topics: Angiotensin II; Animals; beta Catenin; Blood Pressure; Cyclin D1; Fibrosis; Humans; Hypertension; Kidney; Kidney Diseases; Lisinopril; Proto-Oncogene Proteins c-myc; Pyrvinium Compounds; Rats; Signal Transduction

Intermedin/adrenomedullin 2 (IMD/ADM2) is a newly discovered peptide closely related to adrenomedullin. We recently reported that IMD/ADM2 gene transfer could significantly reduce renal ischaemia/reperfusion injury. In this study, we evaluated the effect of IMD/ADM2 on cell proliferation and regeneration in a cultured rat renal tubular epithelial cell line (NRK-52E) of hypoxia-reoxygenation (H/R) injury.. The H/R model in NRK-52E cells consisted of hypoxia for 1 h and reoxygenation for 2 h. IMD/ADM2 was overexpressed in NRK-52E cells using the vector pcDNA3.1-IMD. Enzyme-linked immunosorbent assays were used to measure the concentration of IMD/ADM2 in the culture medium, and real-time PCR and Western blotting were used to determine mRNA and protein levels. In addition, luciferase reporter assays and electrophoretic mobility-shift assays were performed to measure cyclin D1 promoter activity and transcription factor activity.. We found that IMD/ADM2 gene transfer markedly promoted cell viability and decreased lactate dehydrogenase (LDH) activity and cell apoptosis compared with that of H/R. IMD/ADM2 increased the phosphorylation of ERK and decreased the phosphorylation of JNK and P38. Furthermore, IMD/ADM2 promoted cell cycle progression with concomitant increases in the levels of cyclin D1 and cyclin E, and these effects were blocked by the inhibition of ERK, or the agonist JNK and P38. IMD/ADM2 also increased cyclin D1 promoter activity and AP-1 DNA-binding activity.. We demonstrated that IMD/ADM2 promotes renal cell proliferation and regeneration after renal H/R injury by upregulating cyclin D1 and that this upregulation seems to be mediated by the ERK, JNK, and P38 MAPK signalling pathways.

Topics: Adrenomedullin; Animals; Apoptosis; Cell Hypoxia; Cell Line; Cell Proliferation; Cell Survival; Cyclin D1; Cyclin E; Enzyme Activation; Extracellular Signal-Regulated MAP Kinases; Genes, Reporter; JNK Mitogen-Activated Protein Kinases; Kidney Diseases; Kidney Tubules; L-Lactate Dehydrogenase; MAP Kinase Signaling System; p38 Mitogen-Activated Protein Kinases; Phosphorylation; Promoter Regions, Genetic; Rats; Regeneration; Reperfusion Injury; RNA, Messenger; Transcription Factor AP-1; Transfection; Up-Regulation

In renal hyperparathyroidism, parathyroid cell proliferation seems to play a key role in the progression of the disease. Therefore, G1/S transition, a main cell cycle regulatory step, could be deregulated in these patients.. One hundred and one parathyroid glands, taken from parathyroidectomies performed on 41 patients on hemodialysis (HD), and 15 glands, taken from 7 patients with post-transplantation persistent hyperparathyroidism (HPT), were studied. Twelve normal parathyroid (PT) glands were used as the control. Biochemical data, immunohistochemical (IHC) profiles of G1/S transition regulators belonging to the two main pathways (cyclin D1/p16INK4A/pRb and p14ARF/p53/MDM2), and proliferation rate (Ki67) were correlated.. All of the other proteins differed from normal IHC profiles in both groups that showed significant higher proliferating rates, decreases in p27KIP1, pRb, and cyclin D1, as well as increases in p16INK4A, p53, MDM2, and p21WAF1 levels, in comparison with normal PT glands, with the exception of cyclin D3. Contrary to patients with HPT who were on hemodialysis, in post-transplantation HPT, consistent correlations between biochemical data and IHC profiles were obtained.. In both groups IHC profiles of proteins involved in G1/S transition regulation significantly differed from normal PT glands. The results support partial reversion to normal IHC profile in post-transplantation HPT.

Topics: Adult; Aged; Cell Cycle; Cell Cycle Proteins; Cell Division; Cyclin D1; Female; Humans; Hyperparathyroidism, Secondary; Immunohistochemistry; Kidney Diseases; Kidney Transplantation; Male; Middle Aged; Nuclear Proteins; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-mdm2; Renal Dialysis