Electroacupuncture ameliorates knee osteoarthritis in rats via inhibiting NLRP3 inflammasome and reducing pyroptosis

Abstract

Objective: Knee Osteoarthritis (KOA), is the most common joint disease worldwide. The pathogenesis of KOA is complex and electroacupuncture (EA) is an effective therapy for KOA, but the mechanism remains unclear. In this study, we aim to investigate the potential therapeutic effect of EA on the rat model of KOA induced by monosodium iodoacetate (MIA) and its relationship with NLRP3 inflammasome by immunohistochemistry and western blot.
 Methods: KOA was induced by intra-articular injection of MIA (3 mg/50 μL) into the right knee joint of rats. Forty-five male rats weighing 250-300g were randomly divided into 3 groups: control group, KOA group, and KOA + electroacupuncture group (KOA+EA). EA treatment lasted for 2 weeks (6 times a week). Paw withdrawal threshold tests were used to assess mechanical allodynia once a week. Safranin O/Fast Green and hematoxylin and eosin (H&E) staining were used to assess the damage to cartilage, synovium, and subpatellar fat pad (IFP). Immunohistochemistry was used to observe NLRP3 inflammasome-associated protein-positive cells in the same field of view and western blot was used to detect the expression of the associated protein in cartilage tissue.
 Results: The KOA group showed mechanical hyperalgesia, joint inflammation, and significant cartilage tissue destruction. Safranin O/Fast Green and H&E staining revealed that EA alleviated the joint pathological changes caused by KOA and had a protective effect on cartilage, synovium, and IFP destruction. Mechanical allodynia pain and joint swelling were reduced in KOA rats after EA treatment. Immunohistochemistry and western blot showed significant inhibition of NLRP3 inflammasome-associated protein.
 Conclusion: The results indicate that EA can inhibit NLRP3 inflammasome and reduce pyroptosis, which results in the protection of cartilage tissue and the treatment of KOA. It provides reliable evidence for the development of EA in the treatment of KOA and the clinical application of acupuncture.
 
 

Electroacupuncture Ameliorate Juvenile Collagen-Induced Arthritis by Regulating M1 Macrophages and Pyroptosis Signaling Pathways

“…Previous research has substantiated the effectiveness of EA in reducing cartilage damage and abnormal in ammatory responses linked to osteoarthritis [47]; however, the underlying cellular and molecular mechanisms are not yet fully understood. Recent ndings suggest that macrophages can activate cells in the immediate environment to release in ammatory cytokines [48].…”

Electro-acupuncture modulated miR-214 expression to prevent chondrocyte apoptosis and reduce pain by targeting BAX and TRPV4 in osteoarthritis rats

“…The EA needles were inserted to a consistent depth. Alternating strings of dense-sparse frequencies (2/100 Hz EA stimulation, 15 min) were selected as reported previously ( 18 ).…”

Effect of Traditional Chinese Non-Pharmacological Therapies on Knee Osteoarthritis: A Narrative Review of Clinical Application and Mechanism

“… (2) Reducing the expression of NLRP3, ASC, caspase-1, IL-1β and IL-18 in synovium. Zhang et al 107 EA Rats Reducing the contents of IL-1β and IL-18 and the expression of NLRP3, ASC and caspase-1. Central nervous system Regulating the descending pain control system Gao et al 110 Acupuncture Patients Enhancing the FC between dorsal RPN and the right putamen.…”

“…Studies have demonstrated that EA could reduce the contents of IL-1β and IL-18 and the expression of NLRP3, ASC and caspase-1 in synovium of KOA rats. 106,107…”