An experimental model on the protective impact of nanosilymarin on ulcerative colitis induced by TNBS in rats: The inclusion of TLR۴ / NF-κB pathway

Objective(s): The present work aimed to assess the protective impacts of nanosilymarin or silymarin on colitis induced by TNBS in rats. Materials and Methods: Induction of acute colitis was conducted by rectally administering ۲ ml of TNBS solution. About ۲ hr followed by induction of colitis, the rates were given dexamethasone (۲ mg / kg), normal saline, silymarin (۵۰, ۱۰۰, and ۲۰۰ mg / kg), and nanosilymarin (۵۰,۱۰۰, and ۲۰۰ mg / kg) orally for two weeks. Damage was assessed at the macroscopic and microscopic levels. MPO enzyme activity was measured using biochemical technique and also ELISA kit was used to measure tissue levels of TNF-α and IL-۱β and Western blot analysis was utilized to study the expression level of P۶۵ TLR۴ and pNF-κB proteins. According to the results, dexamethasone (۲ mg / kg) and nanosilimarin (۲۰۰ mg / kg) reduced tissue damages than the TNBS group (P<۰.۰۰۱). Moreover, these drugs reduced MPO activity (P<۰.۰۰۱) and levels of TNF-α and IL-۱β (P<۰.۰۰۱) in colon tissue than the TNBS group and also the expression of p۶۵ TLR۴ and pNF-κB proteins was decreased when in comparison to the TNBS group.Conclusion: It is proposed that nanosilimarin reduce colon inflammation in TNBS-induced experimental colitis by inhibition of the TLR۴ / NFκB molecular path.

Keywords:

Colitis , Nanosilymarin , TLR۴/NF-κB , TNBS