ABSTRACT
To study the protective function against oxygen radicals in the mesangial area, we assessed extracellular superoxide dismutase (EC-SOD) production in mesangial cells (MCs) in vitro. These cells have a major protective function against oxygen radicals in the extracellular space. In two different kinds of culture conditions: "growth medium" with fetal cow serum, and "differentiation medium" with reduced growth factor, and four extracellular matrixes; type I collagen, type IV collagen, laminin and fibronectin, were added to the MC culture. With the difference in the culture media, differentiation medium induced EC-SOD hyper-production associated with the both of the slowing down of cell proliferation and the suppression of IL-6 and IL-8 production. With difference in the extracellular matrix, the presence of type VI collagen and laminin promoted higher production of EC-SOD than fibronectin and type I collagen. Type IV collagen and laminin associated with the physiological condition of the glomeruli promoted EC-SOD production compared with the presence of type I collagen and fibronectin dominantly located in pathological condition. Suppression of EC-SOD production in growth medium along with MC proliferation and chemokine hyper-production compared with production in differentiation medium might mimic reduction of the protective capacity against oxygen radical toxity during mesangial proliferation in the glomerular nephritis. MC proliferation with type I collagen and fibronectin might enhance oxygen radical toxity in the glomeruli, and accelerate glomerular sclerosis through the suppression of EC-SOD production.
Subject(s)
Extracellular Matrix/enzymology , Glomerular Mesangium/cytology , Glomerular Mesangium/enzymology , Superoxide Dismutase/biosynthesis , Cell Proliferation , Cells, Cultured , Chemokines/analysis , Culture Media , Humans , Male , Middle Aged , Reactive Oxygen Species/metabolismABSTRACT
The superoxide anion has been implicated in a wide range of diseases. The major protector against superoxide anion in the cell cytosol is Cu,Zn-superoxide dismutase (Cu,Zn-SOD). In this study, anti rat Cu,Zn-SOD was established in murine monoclonal antibodies for the first time. These antibodies were applied to both a highly sensitive EIA system in serum and immunohistochemical methods for detection in gastric mucosa tissues. The proposed EIA method had a high sensitivity within the assay range, 10-300 pg/mL, good percentage, 96.9 +/- 5.60%, and good reproducibility; within-day assay CV = 8.6-10.2%, between-day assay CV = 6.5-11.7%. Inmmunohistochemically, Cu,Zn-SOD localized in the esophagus epithelial cells, gastric oxyntic cells, surface of the gastric lumen side in the small intestine and colonic epithelial cells. The establishment of anti-rat CuZn-SOD monoclonal antibody allows both specific analysis of immunoquantitation in rat Cu,Zn-SOD and highly specific detection of Cu,Zn-SOD location by immunohistochemical methods.
Subject(s)
Antibodies, Monoclonal/immunology , Superoxide Dismutase/immunology , Animals , Antibody Specificity , Female , Immunohistochemistry , Mice , Mice, Inbred BALB C , Rats , Sensitivity and SpecificityABSTRACT
Extracellular superoxide dismutase (EC-SOD) is synthesized in mesenchymally derived cells and prevents the oxygen radical-induced injury. We studied whether kidney mesangial cells (MCs) produce EC-SOD and how its production is associated with chemokine secretion. Under unstimulated condition, MCs produced EC-SOD, and its production was correlated positively with cyclic adenosine monophosphate (cAMP), but negatively with interleukin (IL)-6 or IL-8 production. By prednisolone or phorbol myristate acetate treatment, EC-SOD levels were correlated negatively with levels of IL-6 and IL-8. The presence of adenylate cyclase inhibitor 2',3'-dideoxyadenosine lost the prednisolone effect. The stimulation of EC-SOD production might be one of the important effects of prednisolone via cAMP pathway in MCs.
