lisinopril and nephrin

Nephrin, podocin, CD2AP, and alpha-actinin-4 are important podocyte proteins that help maintain the integrity of the slit diaphragm and prevent proteinuria. Studies have shown that angiotensin-converting enzyme inhibitors, glucocorticoids, and all-trans retinoic acid (ATRA) have antiproteinuric effects. However, it is still unclear whether these drugs, with different pharmacological mechanisms, lead to a reduction in proteinuria by changing the expression and distribution of these important podocyte proteins. In this study, changes in the expression and distribution of nephrin, podocin, CD2AP, and alpha-actinin-4 were dynamically detected in Adriamycin-induced nephrotic (ADR) rats treated with three different drugs: lisinopril, prednisone, and ATRA. Nephropathy was induced by an intravenous injection of Adriamycin. After Adriamycin injection, rats received lisinopril, prednisone, and ATRA treatment, respectively. Renal tissues were collected at Days 3, 7, 14, and 28. The distribution and the expression of messenger RNA and protein of nephrin, podocin, CD2AP, and alpha-actinin-4 were detected by indirect immunofluorescence, real-time polymerase chain reaction, and Western blotting, respectively. With the intervention of lisinopril, prednisone, and ATRA, changes in the expression of nephrin, podocin, and CD2AP were diverse, which was different from that detected in ADR rats. After lisinopril and prednisone intervention, podocin exhibited prominent earlier changes compared with those of nephrin and CD2AP, whereas CD2AP showed more prominent changes after ATRA intervention. There was no change in the expression of alpha-actinin-4 molecule. In summary, we conclude that the antiproteinuric effects of lisinopril, prednisone, and ATRA were achieved by changes in the expression and distribution of the important podocyte molecules nephrin, podocin, CD2AP, and alpha-actinin-4. The pattern in the change of podocyte molecules after lisinopril and prednisone intervention was similar, but the pattern in the change of podocyte molecules after ATRA intervention was different from that of lisinopril or prednisone intervention.

Topics: Actinin; Adaptor Proteins, Vesicular Transport; Angiotensin-Converting Enzyme Inhibitors; Animals; Antibiotics, Antineoplastic; Doxorubicin; Glucocorticoids; Intracellular Signaling Peptides and Proteins; Kidney Glomerulus; Lisinopril; Male; Membrane Proteins; Microfilament Proteins; Nephrosis; Podocytes; Prednisone; Proteinuria; Random Allocation; Rats; Rats, Sprague-Dawley; Tretinoin

Angiotensin-converting enzyme inhibitors restore size-selective dysfunction of the glomerular barrier in experimental animals and humans with proteinuric nephropathies, although the structural and molecular determinants of such an effect are not completely understood. This study used an accelerated model of experimental nephrosis to assess nephrin gene and protein expression in the kidney and the possible modulating effect of drugs that block angiotensin II (AII) synthesis/activity. Passive Heymann nephritis (PHN) and control animals were studied at day 7, month 4, and month 8. Additional PHN rats were treated with lisinopril or AII receptor blocker L-158,809 and studied at 8 mo. Lisinopril and L-158,809 controlled BP, prevented proteinuria, and protected PHN animals from renal injury. An intense signal of nephrin mRNA was detected in glomeruli of control animals mainly restricted to podocytes. In PHN rats, nephrin staining progressively and remarkably decreased with time. Lisinopril and L-158,809 fully prevented the decrease in nephrin transcripts to levels comparable to those of control rats. Consistent with nephrin mRNA expression, immunostaining of the protein showed a progressive decrease in kidneys from PHN rats that was completely abolished by lisinopril and L-158,809. In summary, progressive renal injury was associated with downregulation of nephrin gene that was totally prevented by angiotensin-converting enzyme inhibitor and AII receptor blocker, suggesting that renoprotection afforded by drugs that interfere with AII synthesis/activity was related to an effect on nephrin assembly.

Topics: Angiotensin II; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Animals; Base Sequence; DNA Primers; Glomerulonephritis; Imidazoles; In Situ Hybridization; Kidney Glomerulus; Lisinopril; Male; Membrane Proteins; Proteins; Rats; Rats, Sprague-Dawley; RNA, Messenger; Tetrazoles