Flaxseed Linusorb Alleviates Collagen-Induced Rheumatoid Arthritis in Rats via Inhibiting the TLR4/NF-κb/MAPK Signal Pathway and Modulating Gut Microbiota
Jialong Li, Jing Chen, Xin Shao, Ning Zhang, Yong Wang, Ying Li
Abstract
Flaxseed linusorb (FL) has gradually garnered widespread attention in recent years because of its intriguing bioactivities like anti-inflammation, antimelanogenesis, and even anticancer effects. Based on its proven in vitro anti-inflammatory activity and mechanism, it is supposed that FL may also exhibit an in vivo effect in treating and preventing rheumatoid arthritis (RA). Collagen-induced arthritis (CIA) rat models were established to investigate the potential therapeutic effect of FL, which were intervened with FL via gavage (50 and 100 mg/kg B.W.) and intraperitoneal injection (10 and 20 mg/kg B.W.). After FL treatment, RA clinical symptoms were significantly alleviated, including reduced toe swelling volume and mitigated bone damage in CIA rats. Moreover, a decline in the expression of pro-inflammatory factors (i.e., TNF-α, IL-1β, and IL-6) and RA-related proteins (i.e., MMP-3, COX-2, and 5-LOX) was observed to effectively block the TLR4/NF-κB/MAPK signaling pathway. In addition, FL was discovered to modulate the diversity and composition of intestinal microbiota in CIA rats, where the level of g_Parvibacte, g_Allobaculum, g_Enterococcus, and unclassified_o_Lactobacillales could be significantly increased, whereas the level of Gram-negative bacteria g_Parabacteroides, g_Parasutterella, and g_Paludicola was notably reduced. In conclusion, FL shows promise in RA treatment by inhibiting inflammatory pathways and regulating the gut microbiota.