Molecular docking, dynamics, and preclinical experimental studies identify Morin hydrate as a potent PPAR-γ and NRF-2 transcription factor agonist that mitigates colon inflammation
Authors: Touny Aya , Venkataraman Balaji , Almarzooqui Saeeda , Subramanian Veedamali , Bhongade Bhoomendra , Patil Rajesh , Harjacek Miroslav 
Published: May 2024

Introduction: Peroxisome proliferator-activated receptor gamma (PPAR-γ) plays a vital role in regulating intestine inflammation. PPAR-γ is highly expressed in the adipose tissue and the colon. The nuclear erythroid 2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein1 (Keap1) system protects cells from oxidative stress and inflammation. Therefore, PPAR-γ and Nrf2 ligands offer a drug-targeting system that can be exploited to treat inflammatory bowel diseases (IBDs), especially ulcerative colitis. IBD prevalence is on the rise globally. Current mainstream therapies for IBD offer protection but with many side effects; therefore, up to 30% of IBD patients turn to alternate therapy using bioactive phytochemicals. Morin hydrate, a naturally occurring bioflavonoid in many fruits, stems, and leaves of the Moraceae family plant, possesses potent anti-inflammatory properties. The docking studies reveal that it is a potent activator of the PPAR-γ and Nrf2 transcription factors. Therefore, in this study, we investigated the role of morin hydrate modulating colon epithelial PPAR-γ transcription in colon inflammation. Aim: Therefore, this study aims to investigate morin hydrate’s anti-inflammatory properties using both in vivo and in vitro models of colon inflammation. Methodology: C57BL/6J black mice were administered 2% dextran sodium sulfate (DSS) morin hydrate administered at concentrations of 25 & 50mg/kg body for in vivo studies. The DAI, colon length, MPO, and histology changes were determined. Proinflammatory cytokines (IL-1β, IL-6, TNF-α, & IL17A) were measured using ELISA and mRNA using real-time PCR. PPAR-γ and Nrf2 expression and phosphoNF-κB/NF-κB expression were estimated. HT-29 cells were cultured in DMEM media and were stimulated using TNF-α (1ng/ml). Different concentrations of morin hydrate were treated to HT-29 cells to determine a safe dose range for further in vitro experiments by estimating cell toxicity assay. CXCL-1, IL-8, and mRNA levels were determined using real-time PCR after morin hydrate co-treatment. Morin hydrate effect on PPAR-γ and Nrf2 promoter activity was determined using full-length promoter transfection studies. Results: Morin treatment significantly ( p<0.01) decreased DAI, MPO level, and restored colon length dose-dependently in the treated group. Histological scoring for colonic inflammation was significantly ( p<0.001) improved upon morin treatment. Morin treatment also inhibited the proinflammatory cytokines (IL-1β, IL-6, TNF-α, & IL17A) significantly ( p<0.01) both at protein and mRNA levels. Morin significantly inhibited COX-2 and iNOS both at protein and mRNA levels and also decreased tissue nitrite levels. Morin also activated PPAR-γ protein expression NRF2 nuclear translocation and inhibited NF-κB expression in DSS-administered mice. Morin significantly decreased antioxidant surrogate markers superoxide dismutase (SOD) and catalase activity. Morin significantly ( p<0.01) decreased proinflammatory cytokine (CXCL-1 & IL-8) mRNA expression when HT-29 cells were challenged with TNF-α. Morin also increased PPAR-γ and Nrf2 promoter activity. Conclusion: Morin hydrate is a potent PPAR-γ and Nrf2 transcription factor activator that mitigates colon inflammation through its anti-inflammatory and antioxidant activities.

This is supported from UAE University grant, fund number 12R006 and 12R169.

This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.