nifuroxazide and Fibrosis

The current work explored the influences of nifuroxazide, an in vivo inhibitor of signal transducer and activator of transcription-3 (STAT-3) activation, on tubulointerstitial fibrosis in rats with obstructive nephropathy using unilateral ureteral obstruction (UUO) model. Thirty-two male Sprague Dawley rats were assigned into 4 groups (n = 8/group) at random. Sham and UUO groups were orally administered 0.5% carboxymethyl cellulose (CMC) (2.5 mL/kg/day), while Sham-NIF and UUO-NIF groups were treated with 20 mg/kg/day of NIF (suspended in 0.5% CMC, orally). NIF or vehicle treatments were started 2 weeks after surgery and continued for further 2 weeks. NIF treatment ameliorated kidney function in UUO rats, where it restored serum creatinine, blood urea, serum uric acid and urinary protein and albumin to near-normal levels. NIF also markedly reduced histopathological changes in tubules and glomeruli and attenuated interstitial fibrosis in UUO-ligated kidneys. Mechanistically, NIF markedly attenuated renal immunoexpression of E-cadherin and α-smooth muscle actin (α-SMA), diminished renal oxidative stress (↓ malondialdehyde (MDA) levels and ↑ superoxide dismutase (SOD) activity), lessened renal protein expression of phosphorylated-STAT3 (p-STAT-3), phosphorylated-Src (p-Src) kinase, the Abelson tyrosine kinase (c-Abl) and phosphorylated nuclear factor-kappaB p65 (pNF-κB p65), decreased renal cytokine levels of transforming growth factor-β1 (TGF-β1), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and monocyte chemoattractant protein-1 (MCP-1) and reduced number of cluster of differentiation 68 (CD68) immunolabeled macrophages in UUO renal tissues, compared to levels in untreated UUO kidneys. Taken together, NIF treatment suppressed interstitial fibrosis in UUO renal tissues, probably via inhibiting STAT-3/NF-κB signaling and attenuating renal oxidative stress and inflammation.

Topics: Animals; Fibrosis; Hydroxybenzoates; Inflammation; Kidney; Kidney Diseases; Male; NF-kappa B; Nitrofurans; Oxidative Stress; Rats; Rats, Sprague-Dawley; Signal Transduction; STAT3 Transcription Factor; Ureteral Obstruction; Uric Acid

Diabetic nephropathy (DN) is a serious complication of diabetes mellitus. Moreover,it is amongst the most common causes of end-stage renal failure. Inflammation is a crucial player in both development and progression of DN. JAK2/STA3 is a pleotropic cascade reported to regulate diverse inflammatory events. Previous studies reported involvement of JAK2/STA3 signal transduction pathway in diabetes-associated renal injury. In the current study, the inhibitory effect of nifuroxazide (25 mg/kg/day, orally) against inflammatory condition associating diabetic kidney progression in rats was evaluated. The underlying hypothesis is mainly via the inhibitory effect of nifuroxazide on STAT3 signaling. Results revealed that nifuroxazide effectively inhibited STAT3 activation in diabetic male rats, improved glomerular filtration function, protected against diabetes-induced histopathological and ultramicroscopic structural alterations. Further, nifuroxazide treatment significantly reduced renal macrophage infiltration and fibrosis and decreased mRNA and protein levels of TNF-α and IL-18 in diabetic renal tissue. The current findings shed the light on nifuroxazide's efficacy as an alternative anti-inflammatory therapy to hinder the development and progression of DN in diabetic patients mainly via STAT3 inhibition.

Topics: Animals; Anti-Inflammatory Agents; Blood Urea Nitrogen; Creatine; Diabetes Mellitus, Experimental; Diabetic Nephropathies; Fibrosis; Hydroxybenzoates; Interleukin-18; Janus Kinase 2; Kidney; Kidney Function Tests; Macrophages; Male; Microscopy, Electron; Nitrofurans; Rats; Signal Transduction; STAT3 Transcription Factor; Streptozocin; Tumor Necrosis Factor-alpha