Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04179 (MnSOD)
 2,777 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sublethal renal ischemia induces tubular epithelium damage and kidney dysfunction. Using NRK-52E rat proximal tubular epithelial cells, we have established an in vitro model, which includes oxygen and nutrients deprivation, to study the proximal epithelial cell response to ischemia. By means of this system, we demonstrate that confluent NRK-52E cells lose monolayer integrity and detach from collagen IV due to: (i) actin cytoskeleton reorganization; (ii) Rac1 and RhoA activity alterations; (iii) Adherens junctions (AJ) and Tight junctions (TJ) disruption, involving redistribution but not degradation of E-cadherin, beta-catenin and ZO-1; (iv) focal adhesion complexes (FAC) disassembly, entangled by mislocalization of paxillin and FAK dephosphorylation. Reactive oxygen species (ROS) are generated during the deprivation phase and rapidly balanced at recovery involving MnSOD induction, among others. The use of antioxidants (NAC) prevented FAC disassembly by blocking paxillin redistribution and FAK dephosphorylation, without abrogating AJ or TJ disruption. In spite of this, NAC did not show any protective effect on cell detachment. H(2)O(2), as a pro-oxidant treatment, supported the contribution of ROS in tubular epithelial cell-matrix but not cell-cell adhesion alterations. In conclusion, ROS-mediated FAC disassembly was not sufficient for the proximal epithelial cell shedding in response to sublethal ischemia, which also requires intercellular adhesion disruption.
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PMID:Requirements for proximal tubule epithelial cell detachment in response to ischemia: role of oxidative stress. 1702 98

Standard cell culture conditions do not reflect the physiological environment in terms of oxygen tension (20% vs 3%). The effects of lowering oxygen tension on cell proliferation in culture can be beneficial as well as detrimental depending on the cell line studied, but the molecular mechanism underlying such effects is not fully understood. We observed that the proliferative capacity of the rat cell lines NRK and INS-1 was inhibited when cultured under 3% oxygen as compared to 20% oxygen. Suppression of proliferation in NRK cells was accompanied by induction of DNA double strand breaks whereas in INS-1 cells it was accompanied by up-regulation of p53 and p27. Although Sirt1 was up-regulated in both cell lines by 3% oxygen the effects on antioxidant enzymes (MnSOD, CuZnSOD and catalase) were cell line specific. Marked up-regulation of heme oxygenase-1 (HO-1) was detected in both NRK and INS-1 cells when cultured in 3% oxygen. HO-1 expression can be readily induced by exposure to hydrogen peroxide in culture. These results suggest that reduced oxygen tension suppresses the proliferative capacity of these two cell lines through a stress response that is similar to an oxidative stress response but the molecular events that lead to the reduced cell proliferation are cell line specific.
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PMID:Adverse effects of reduced oxygen tension on the proliferative capacity of rat kidney and insulin-secreting cell lines involve DNA damage and stress responses. 1869 96

Saikosaponin-d (Ssd) is one of the major pharmacologically active molecules present in Bupleurum falcatum L, a medical herb against inflammatory diseases in the traditional Chinese medicine. In the current study, we investigated the protective activity of Ssd on diabetic nephropathy along with the underlying mechanisms using renal tubular epithelial cell line (NRK-52E). Our study showed that high glucose stimulation significantly increased NRK-52E cell proliferation. Ssd administration dramatically inhibited high glucose-induced proliferation and DNA synthesis in NRK-52E cell. In addition, high glucose treatment resulted in oxidative stress as shown by increased production of ROS, higher concentration of MDA, and decreased activity of SOD. However, incubation with Ssd reversed such changes in NRK-52E cells. On the molecular level, Ssd also increased the mRNA levels of IDH2 and MnSOD. Moreover, Ssd-treated NRK-52E cells displayed a dramatic enhancement in SIRT3 expression both at mRNA and protein levels. Down-regulation of SIRT3 abolished the protective effects of Ssd on NRK-52E cells. These findings demonstrated that Ssd protected renal tubular epithelial cell against high glucose induced injury via upregulation of SIRT3.
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PMID:Saikosaponin-d protects renal tubular epithelial cell against high glucose induced injury through modulation of SIRT3. 2613 Dec 75