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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Cells, Cultured, Coloring Agents, Erythropoietin, Extracellular Matrix, Extracellular Matrix Proteins, Kidney Glomerulus, Podocytes, Primary Cell Culture, Rats, Receptors, Erythropoietin, Recombinant Proteins, Tetrazolium Salts, Thiazoles.
user
Are the protective effects of erythropoietin on rat glomerular podocytes in culture modulated by extracellular matrix proteins? Context: Podocytes are typically cultured on collagen I; however, collagen I is absent from healthy glomerular basement membranes. Erythropoietin (EPO) is thought to protect podocytes in vivo. Here, we studied how various types of extracellular matrix (ECM) proteins and EPO affect podocytes in culture. Primary rat podocytes were replated on collagen I, collagen IV, whole ECM extract, laminin, or bare plastic. Cellular adhesion (8 hours after plating), proliferation (5 days, 10 % serum), and resistance to serum deprivation (3 days, 0.5 % serum) were assessed. BrdU incorporation and expression of podocyte-specific markers were employed as measures of cellular proliferation and differentiation, respectively. qPCR was used to verify expression of EPO receptor in cultured podocytes. Cellular adhesion was similar on all ECM proteins and unaffected by EPO. Proliferation was accelerated by laminin and the ECM extract, but the final cell density was similar on all ECM surfaces. Collagen IV supported the serum-deprived cells better than the other ECM proteins. EPO (2-20 ng/ml) improved viability of serum-deprived podocytes on collagen I, collagen IV, and ECM, but not on laminin or bare plastic. The cells expressed mRNA for EPO receptor.
assistant
The physiological ECM proteins are more supportive of primary podocytic cultures compared with collagen I. The protective effects of EPO during serum deprivation are modulated by the cultivation surface. Final Decision: yes