TY - JOUR
T1 - Glomerular endothelial cell proteoglycans - regulation by TGF-β1
AU - Kasinath, B. S.
PY - 1993
Y1 - 1993
N2 - Glomerular endothelial cells (G-Endo) may participate in the synthesis of glomerular basement membrane. We studied the metabolism of proteoglycans and its regulation by TGF-β1 in bovine G-Endo. The synthesis of cell layer and medium-associated [35S]SO4-labeled macromolecules was significantly increased by TGF-β1. On ion exchange chromatography, 80-90% of the 35S-labeled macromolecules in the control medium and cell layer were found to be proteoglycans; TGF-β1 increased their synthesis by 1.8-fold but did not alter the anionic charge density. On dissociative Sepharose CL-4B chromatography, the medium proteoglycans were distributed into two peaks of Kav 0.22 (M-I) and 0.44 (M-II). Digestion procedures showed that 39% and 57% of peaks M-I and M-II consisted of HSPG, the remainder being CS/DSPG. The HSPG in peak M-II has the same hydrodynamic size as HSPG present in bovine glomerular basement membrane (N. Parthasarathy and R. G. Spiro, 1987, J. Biol. Chem. 259:12749). Cell layer proteoglycans also resolved into two peaks of Kav 0.33 (C-I) and 0.63 (C-II), respectively, on Sepharose CL-4B chromatography; 39 and 45% of these peaks were made of HSPG. TGF-β1 increased the synthesis of CS/DSPG in the media by three-fold without affecting the synthesis of HSPG. Our data suggest that G-Endo may participate in synthesis of glomerular matrix HSPG under physiologic conditions; regulation of G-Endo proteoglycans by TGF-β1 may be of relevance in glomerular diseases characterized by matrix expansion.
AB - Glomerular endothelial cells (G-Endo) may participate in the synthesis of glomerular basement membrane. We studied the metabolism of proteoglycans and its regulation by TGF-β1 in bovine G-Endo. The synthesis of cell layer and medium-associated [35S]SO4-labeled macromolecules was significantly increased by TGF-β1. On ion exchange chromatography, 80-90% of the 35S-labeled macromolecules in the control medium and cell layer were found to be proteoglycans; TGF-β1 increased their synthesis by 1.8-fold but did not alter the anionic charge density. On dissociative Sepharose CL-4B chromatography, the medium proteoglycans were distributed into two peaks of Kav 0.22 (M-I) and 0.44 (M-II). Digestion procedures showed that 39% and 57% of peaks M-I and M-II consisted of HSPG, the remainder being CS/DSPG. The HSPG in peak M-II has the same hydrodynamic size as HSPG present in bovine glomerular basement membrane (N. Parthasarathy and R. G. Spiro, 1987, J. Biol. Chem. 259:12749). Cell layer proteoglycans also resolved into two peaks of Kav 0.33 (C-I) and 0.63 (C-II), respectively, on Sepharose CL-4B chromatography; 39 and 45% of these peaks were made of HSPG. TGF-β1 increased the synthesis of CS/DSPG in the media by three-fold without affecting the synthesis of HSPG. Our data suggest that G-Endo may participate in synthesis of glomerular matrix HSPG under physiologic conditions; regulation of G-Endo proteoglycans by TGF-β1 may be of relevance in glomerular diseases characterized by matrix expansion.
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U2 - 10.1006/abbi.1993.1434
DO - 10.1006/abbi.1993.1434
M3 - Article
C2 - 8373175
AN - SCOPUS:0027270920
VL - 305
SP - 370
EP - 377
JO - Archives of Biochemistry and Biophysics
JF - Archives of Biochemistry and Biophysics
SN - 0003-9861
IS - 2
ER -