RESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Rheumatoid arthritis (RA) is a multifactorial, polygenic inflammatory disease. Mesua assamica (King & Prain) Kosterm. (MA) is an endangered medicinal plant indigenous to South Asia, primarily to Assam in India. The tree bark is claimed to possess anti-inflammatory, anti-diabetic, anti-cancer, and anti-malarial properties; nevertheless, its role in RA has not been elucidated. Hence, this study aims to investigate the in-vitro and in-vivo anti-arthritic effects of Mesua assamica bark ethanolic extract (MAE). AIM OF THE STUDY: This study aims to investigate the anti-rheumatic potential of MAE in-vitro on RAW 264.7 cells for its anti-oxidant and anti-inflammatory activities and in-vivo on the CFA-induced adjuvant arthritis in the rat model. MATERIALS AND METHODS: We investigated the possible therapeutic effects of MAE in-vitro using RAW 264.7 cells triggered by LPS. Meanwhile, adult Wistar rats were injected intradermally with 100 µl of CFA to induce arthritis, and they were given MAE orally at doses of 100 and 200 mg/kg for up to 28 days. Paw volume analysis, X-ray radiography, anti-oxidant levels analysis, gene and protein expression studies, and histological analysis were carried out to assess the effects of MAE in-vivo. RESULTS: MAE significantly mitigated the inflammation by reducing ROS levels and dropped the nitrite, PGE2, and COX-2 levels enhanced by LPS in-vitro. At the same time, MAE treatment reduced the paw and joint inflammation and increased the immune organ index in the CFA rats. Histopathology data revealed that MAE mitigated the CFA-induced lesions of the ankle joints and synovial tissues. Similarly, MAE significantly abated the secretion of pro-inflammatory cytokines, inhibited the protein expression of TLR4, NF-кB, COX-2, and iNOS, as well as improved the Nrf2 and HO-1 levels in-vitro and in-vivo. CONCLUSION: All the results highlighted the anti-rheumatic potential of MAE in RA in-vitro and in-vivo by inhibiting the TLR4/NF-кB/COX-2/iNOS and promoting the Nrf2/HO-1 signaling axis.
Asunto(s)
Artritis Experimental , Artritis Reumatoide , Ciclooxigenasa 2 , Etanol , Factor 2 Relacionado con NF-E2 , FN-kappa B , Corteza de la Planta , Extractos Vegetales , Receptor Toll-Like 4 , Animales , Extractos Vegetales/farmacología , Células RAW 264.7 , Ratones , Corteza de la Planta/química , Receptor Toll-Like 4/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Artritis Reumatoide/tratamiento farmacológico , FN-kappa B/metabolismo , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/patología , Etanol/química , Ciclooxigenasa 2/metabolismo , Masculino , Ratas , Ratas Wistar , Regulación hacia Abajo/efectos de los fármacos , Antiinflamatorios/farmacología , Antiinflamatorios/aislamiento & purificación , Antioxidantes/farmacología , Transducción de Señal/efectos de los fármacos , Hemo Oxigenasa (Desciclizante)/metabolismo , Antirreumáticos/farmacología , Antirreumáticos/aislamiento & purificación , Hemo-Oxigenasa 1/metabolismo , Proteínas de la MembranaRESUMEN
Ulcerative colitis (UC) is an idiopathic, chronic disorder of the intestines characterized by excessive inflammation and oxidative stress. Loganic acid (LA) is an iridoid glycoside reported to have antioxidant and anti-inflammatory properties. However, the beneficial effects of LA on UC are unexplored yet. Thus, this study aims to explore the potential protective effects of LA and its possible mechanisms. In-vitro models were employed using LPS-stimulated RAW 264.7 macrophage cells, and Caco-2 cells, whereas an in-vivo model of ulcerative colitis was employed using 2.5% DSS in BALB/c mice. Results indicated that LA significantly suppressed the intracellular ROS levels and inhibited the phosphorylation of NF-κB in both RAW 264.7 and Caco-2 cells, contrarily LA activated the Nrf2 pathway in RAW 264.7 cells. In DSS-induced colitis mice, LA significantly alleviated the inflammation and colonic damage by decreasing the pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α, and IFN-γ), oxidative stress markers (MDA, and NO), and also expression levels of various inflammatory proteins (TLR4 and NF-кB) which was evidenced by immunoblotting. On the contrary, the release of GSH, SOD, HO-1, and Nrf2 were profoundly increased upon LA treatment.Subsequently, molecular docking studies showed that LA interacts with active site regions of target proteins (TLR4, NF-κB, SIRT1, and Nrf2) through hydrogen bonding and salt bridge interaction. The current findings demonstrated that LA could exhibit a protective effect in DSS-induced ulcerative colitis through its anti-inflammatory and anti-oxidant effects via inactivating the TLR4/NF-κB signaling pathway and activating the SIRT1/Nrf2 pathways.