Labisia pumila prevented osteoarthritis cartilage degeneration by attenuating joint inflammation and collagen breakdown in postmenopausal rat model

The tropical herb Labisia pumila is traditionally used in facilitating childbirth and post-partum care. The effects of L. pumila leaf extract (LP) in explant cartilage culture and on postmenopausal osteoarthritis (OA) rat model were assessed. The LP (10, 25 and 50 µg/ml) or diclofenac (10 µg/ml) was added to the cartilage explants containing bovine IL-1β (20 ng/ml), to evaluate their direct effects on cartilage degradation. In the preclinical study, rats were grouped (n = 8) into: non-treated OA; OA + diclofenac (5 mg/kg); OA + LP extract (150 and 300 mg/kg); and healthy control. To induce OA, monosodium iodoacetate was injected into the ovariectomised female rats' intra-articular knee joints and evaluated for OA severity after 8 weeks via physical (radiological, macroscopic and histological observations), biochemical, ELISA and mRNA expression analysis (for inflammation and cartilage degradation biomarkers). The LP reduced the nitric oxide and proteoglycan release from the cartilage explants under IL-1β induction. The radiological, macroscopic, microscopic and histological images showed the OA rats treated with LP and diclofenac had significantly reduced osteophytes and cartilage erosions compared to non-treated OA rats. The extract significantly up-regulated the anti-inflammatory interleukin-10, collagen type II and down-regulated pro-inflammatory PTGS2 (prostaglandin-endoperoxide synthase 2) mRNA expressions compared to non-treated control. The LP treatment significantly reduced serum collagenases (MMP-1 and MMP-3) and collagen type II degradation biomarker (CTX-II) levels in OA rats. The LP containing myricetin and gallic acid suppressed inflammation, collagenases and cartilage degradation, and helped cartilage matrix synthesis, to prevent OA at the dose equivalent to 30-60 mg/kg daily for humans.