Effects of Warm Needling on Cartilage Injury in Rats with Knee Osteoarthritis via Regulating Cuproptosis

Abstract

Objective

This study was designed to evaluate the effects of warm needling on cartilage damage in rats with knee osteoarthritis (KOA) and to elucidate its relationship with cuproptosis.

Methods

Forty Wistar rats were randomly divided into four groups: normal group, model group, mild-warm moxibustion group, and warm needling group, with 10 rats in each group. The KOA model was established by intra-articular injection of monosodium iodoacetate (MIA). Four weeks after model induction, rats in the mild-warm moxibustion group and the warm needling group received respective interventions at the acupoints “Futu” (ST32) and “Zusanli” (ST36), while rats in the other groups were only restrained under identical conditions. Each session lasted 30 min and was administered every other day, for a total of 14 sessions.

Results

Compared with the model group, both intervention groups significantly improved the morphology and structure of chondrocytes and mitochondria and significantly increased paw withdrawal threshold and knee range of motion (P < 0.05). Copper ion (Cu²⁺) and interleukin-2 (IL-2) levels were significantly decreased (P < 0.05), while interleukin-10 (IL-10) level was significantly increased (P < 0.05). The expression levels of heat shock protein 70 (HSP70), ferredoxin 1 (FDX1), and dihydrolipoamide S-acetyltransferase (DLAT) were significantly downregulated (P < 0.05), whereas pyruvate dehydrogenase E1 beta subunit (PDHB) expression was significantly upregulated (P < 0.05). Compared with the mild-warm moxibustion group, the warm needling group showed significantly greater improvements in behavioral outcomes, biochemical parameters, and cuproptosis-related protein expression (P < 0.05).

Conclusion

Warm needling alleviated cartilage injury in KOA rats, possibly by regulating the expression of cuproptosis-related proteins and regulating cuproptosis.