Abstract:
The potential of the fruit peels of mango, orange, cantaloupe, and pomegranate in
the treatment of osteoarthritis (OA) was evaluated in a rat model. Their metabolic
profiles were characterized using ultrahigh‐performance liquid chromatography
(UPLC)–electrospray ionization‐mass spectroscopy and 66 albino rats were intra‐
articularly injected with monosodium iodoacetate in the knee joints. The extracts
were orally administered at doses of 200 and 400 mg/kg for 28 days. Serum levels of
IL‐6 and tissue levels of cyclooxygenase‐2 (COX‐2), peroxisome proliferator‐
activated receptor‐gamma (PPARγ), and alpha‐smooth muscle actin (α‐SMA) were
measured using ELISA. COL1A1 expression was measured by quantitative
polymerase chain reaction. Histopathological changes in the joints were examined.
In the extracts, 85 metabolites were annotated, and the levels of interleukin (IL)‐6,
COX‐2, α‐SMA, malondialdehyde, and nitric oxide were significantly reduced, while
PPARγ and glutathione levels were significantly raised in all treated groups
compared to the OA group. All extracts downregulated the cartilage mRNA
expressions for COL1A1 dose‐dependently. Mango peel extract exhibited the best
chondroprotective effect. The in silico study showed the link between mango extract
metabolites and COX‐2.