nsc-74859 and Nephritis--Interstitial

It is high incidence of tubulointerstitial lesion (TIL) in lupus nephritis (LN) and TIL can affect the prognosis of patients with LN. Signal transducer and activator of transcription (STAT) 3 was activated in LN and STAT3 inhibition could delay the onset of LN. Here, we evaluated the role of a well-known STAT3 inhibitor, S3I-201, on TIL in lupus nephritis. STAT3 was activated in MRL/lpr mice (a mouse model of lupus nephritis), and treatment with S3I-201 inhibited the activation of it. The level of 24-h urine protein and nitrogen urea increased in MRL/lpr mice and adminstration of S3I-201 reduced the level of urinary protein. In addition, S3I-201 attenuated the expression of α-smooth muscle actin (α-SMA), Fibronectin (FN) proteins, as well as the expression of monocyte chemotactic factor-1 (MCP-1) and intercellular adhesion molecule (ICAM-1). However, the expression of E-cadherin improved when treatment with S3I-201. These results revealed that the activation of STAT3 mediates tubulointerstitial lesion in mice with LN. S3I-201, by suppressing STAT3 activity, has therapeutic effect in lupus nephritis.

Topics: Aminosalicylic Acids; Animals; Benzenesulfonates; Blood Urea Nitrogen; Creatinine; Disease Models, Animal; Female; Kidney; Lupus Nephritis; Mice; Mice, Inbred MRL lpr; Nephritis, Interstitial; Proteinuria; Signal Transduction; STAT1 Transcription Factor; STAT3 Transcription Factor

Accumulation of both interstitial myofibroblasts and excessive production of extracellular matrix proteins is a common pathway contributing to chronic kidney disease. In a number of tissues, activation of STAT3 (signal transducer and activator of transcription 3) increases expression of multiple profibrotic genes. Here, we examined the effect of a STAT3 inhibitor, S3I-201, on activation of renal interstitial fibroblasts and progression of renal fibrosis. Treatment of cultured rat renal interstitial fibroblasts with S3I-201 inhibited their activation, as evidenced by dose- and time-dependent blockade of alpha-smooth muscle actin and fibronectin expression. In a mouse model of renal interstitial fibrosis induced by unilateral ureteral obstruction, STAT3 was activated, and administration of S3I-201 attenuated both this activation and extracellular matrix protein deposition following injury. S3I-201 reduced infiltration of the injured kidney by inflammatory cells and suppressed the injury-induced expression of fibronectin, alpha-smooth muscle actin, and collagen type-1 proteins, as well as the expression of multiple cytokines. Furthermore, S3I-201 inhibited proliferation and induced apoptosis preferentially in renal interstitial fibroblasts of the obstructed kidney. Thus, our results suggest that increased STAT3 activity mediates activation of renal interstitial fibroblasts and the progression of renal fibrosis. Inhibition of STAT3 signaling with S3I-201 may hold therapeutic potential for fibrotic kidney diseases.

Topics: Aminosalicylic Acids; Animals; Benzenesulfonates; Cell Line; Cells, Cultured; Disease Models, Animal; Extracellular Matrix Proteins; Fibroblasts; Fibrosis; Kidney Diseases; Kidney Failure, Chronic; Male; Mice; Mice, Inbred C57BL; Nephritis, Interstitial; Rats; Renal Insufficiency, Chronic; STAT3 Transcription Factor; Ureteral Obstruction