Oral Administration of Salmon Cartilage Proteoglycan Attenuates Osteoarthritis in a Monosodium Iodoacetate-Induced Rat Model

Abstract

Proteoglycan (PG) is a type of glycoprotein which forms an extracellular matrix with collagen and hyaluronic acid to maintain articular cartilage, synovial membrane, and synovial fluid. This study aimed to evaluate the antiosteoarthritis effects of salmon nasal cartilage-derived PG in alleviating knee osteoarthritis in an osteoarthritis rat model. Knee osteoarthritis was induced in rats by intra-articular injection of monosodium iodoacetate (MIA), 3 mg/knee, to the right knee. Animals were then administered either diclofenac (3 mg/kg body weight [b.w]/day) or proteoglycan F (PGF; 40 mg/kg and 120 mg/kg b.w/day) by oral gavage for 6 consecutive weeks. Knee diameters were measured throughout the experimental period; serum interleukin-1β and tumor necrosis factor-alpha (TNF-α) levels, and histological analysis of the ligament were carried out at the end of the experiment. Salmon cartilage PG considerably alleviated the osteoarthritis symptoms in the model and lowered the serum concentrations of interleukin-1β and TNF-α. Diclofenac 3 mg/kg/day and PGF at doses of 40 mg/kg/day and 120 mg/kg/day also improved articular cartilage structure on further histological studies. This study demonstrated the in vivo effect of salmon cartilage PG in attenuating symptoms in an MIA-induced rat model, including reduction of inflammatory markers and histological improvement of cartilage tissue.

The efficacy and tolerability of proteoglycan F in the treatment of knee osteoarthritis: A prospective, randomized, double-blind controlled trial

“…This shows the advantage of the MRI method when it is possible to detect very small structural changes that ultrasound cannot detect. Indeed, although the exact mechanism by which salmon nasal cartilage exerts its protective effects on cartilage structure is still to be elucidated, proteoglycan has been shown to possibly have anti-inflammatory effects through inhibition of inflammatory cytokine production IL-1, IL-6, TNF-α, and immunomodulation in vitro and in vivo [ 19 , 20 , 38 , 39 ]. Furthermore, salmon nasal proteoglycan was shown to promote chondrocyte proliferation and innate PG production, thereby providing an anti-inflammatory and chondroprotective effect in the joint tissue [ 20 ].…”

“…Proteoglycan F (PGF) was manufactured in the form of a hard capsule (50 ​mg in a capsule) by Astrim, INC (2006, Kobora, Yamada-cho, Mizunami-Shi, Gifu, Japan - GMP Certification No.12806) and consisted of 12.5 ​mg salmon nasal cartilage extract (containing 10 ​mg proteoglycan) and 37.5 ​mg dextrin (as a vehicle). Salmon proteoglycan was extracted from salmon ( Oncorhynchus keta ) nasal cartilage, as in previous studies [ 18 , 19 ].…”

“…Recent studies have demonstrated the safety and efficacy of proteoglycan in rats, rabbits, and individuals with knee joint discomfort but without a diagnosis of OA [ 15 , [18] , [19] , [20] ]. Previous studies found that using a proteoglycan-containing product effectively reduced knee pain and improved knee function in people with knee pain or osteoarthritis [ 21 , 22 ].…”