Ciprofloxacin has antifibrotic effects in scleroderma fibroblasts via downregulation of Dnmt1 and upregulation of Fli1

Abstract

Systemic sclerosis (SSc) is characterized by fibrosis of the skin and internal organs. The present study was undertaken to examine the effects of ciprofloxacin, a fluoroquinolone antibiotic implicated in matrix remodeling, on dermal and lung fibroblasts obtained from SSc patients. Dermal and lung fibroblasts from SSc patients and healthy subjects were treated with ciprofloxacin. Western blotting was used to analyze protein levels and RT-PCR was used to measure mRNA expression. The pharmacologic inhibitor UO126 was used to block Erk1/2 signaling. SSc dermal fibroblasts demonstrated a significant decrease in collagen type I mRNA and protein levels after antibiotic treatment, while healthy dermal fibroblasts were less sensitive to ciprofloxacin, downregulating collagen only at the protein levels. Connective tissue growth factor (CCN2) gene expression was significantly reduced and matrix metalloproteinase 1 (MMP1) levels were enhanced after ciprofloxacin treatment to a similar extent in healthy and SSc fibroblasts. Ciprofloxacin induced Erk1/2 phosphorylation, and Erk1/2 blockade completely prevented MMP1 upregulation. However, Smad1 and Smad3 activation in response to TGFβ was not affected. The expression of friend leukemia integration factor 1 (Fli1), a transcriptional repressor of collagen, was increased after treatment with ciprofloxacin only in SSc fibroblasts, and this was accompanied by a decrease in the levels of DNA methyltransferase 1 (Dnmt1). Similar effects were observed in SSc-interstitial lung disease (ILD) lung fibroblasts. In summary, our study demonstrates that ciprofloxacin has antifibrotic actions in SSc dermal and lung fibroblasts via the downregulation of Dnmt1, the upregulation of Fli1 and induction of MMP1 gene expression via an Erk1/2-dependent mechanism. Thus, our data suggest that ciprofloxacin may be an attractive therapy for SSc skin and lung fibrosis.

The dark side of fluoroquinolones

“…Metalloproteases and their inhibitors are intertwined and form a basis for a metabolic matrix tissue stability that may be interrupted pharmacologically. This theory is in line with previous observations revealing antifibrotic activity 8 and decreased collagen-1 protein expression with fluoroquinolones. 9 The enigmatic puzzle of the progression of some aortic events may alarmingly be iatrogenic, and the clinician may wisely consider a prudent use of fluoroquinolones in patients with aortic dilatation.…”

Unfolding the pathogenesis of scleroderma through genomics and epigenomics

“…They showed that addition of the DNMT inhibitor 2-deoxy-5-azacytidine (5-aza) and HDAC inhibitor trichostatin A (TSA) decreased collagen content in SSc fibroblasts, possibly through normalizing the hypermethylated and hypoacetylated promoter region of the collagen suppressor gene Friend leukemia integration 1 (FLI1), hence increasing Fli-1 expression. The impact of DNA methylation on FLI1 expression was further confirmed by Bujor et al [92]. They showed that the antifibrotic effect of ciprofloxacin, a broad spectrum antibiotic, in SSc dermal fibroblasts and SSc-interstitial lung disease lung fibroblasts stemmed from downregulation of DNMT1 and upregulation of FLI1.…”

Treatment of rapidly progressive systemic sclerosis: current and futures perspectives

“…Also, multiple existing drugs that might be repurposed to treat fibrosis [134] such as the peroxisome proliferator-activated receptor-γ agonists, rosiglitazone [135], statins [136,137], fluoroquinolone antibiotics such as ciprofloxacin [138,139], and thrombin inhibitors such as dabigatran [140], are being considered. However, given that the pathogenic mechanisms of fibrotic diseases in SSc are quite complex with multiple and often redundant pathways, blocking a single molecule or pathway will likely not be sufficient.…”