Consumption of Saturated Fatty Acids-Rich Lard Benefits Recovery of Experimental Arthritis by Activating PPAR-γ

Scope: This study investigates the impacts of lard and related fatty acids intake on rheumatoid arthritis (RA) animal models. Method and results: Collagen-induced arthritis (CIA) and adjuvant-induced arthritis (AIA) are induced in SD rats and C57 BL/6 mice respectively, which are fed by lard-rich diet (LRD) for 42 days with intake restriction or not. AIA SD rats are treated by representative fatty acids for 30 days. Body weight, arthritis score, and metabolic profile are periodically recorded. Monocyte distribution, cytokine/metabolites levels, gene expression, and tissue damages are investigated by flow cytometry, ELISA, colorimetry, PCR, and histological methods. After being treated by fatty acids in vitro, THP-1 monocytes and the corresponding medium are collected for ELISA, PCR, immunoblotting, and reporter gene assays. Irrespective of intake amounts, LRD decreases inflammatory cytokines and inhibits glycolysis in all rheumatic rodents. Furthermore, it alters monocyte distribution and promotes PPAR-gamma expression in AIA mice. Overall evidences show that both saturated (SF) and unsaturated fatty acids (USF) from lard can attenuate inflammation by activating PPAR-gamma. Silencing PPAR-gamma abrogates their anti-inflammatory effects in vitro. Besides, SF can stimulate TLR4/NF-kappa B pathway. Conclusion: Lard consumption is beneficial for active inflammatory arthritis recovery. Even SF can activate PPAR-gamma and consequently attenuate inflammation.

Automated summary

This study investigates the effects of lard and related fatty acids intake on rheumatoid arthritis animal models. The results show that lard consumption can attenuate inflammation in rheumatic rodents by activating PPAR-gamma, regardless of intake amounts.