Effects of undernatured collagen supplementation on rat knee osteoarthritis
C. Marques de Araújo Osteoarthritis and Cartilage VOLUME 28, SUPPLEMENT 1, S215-S216, APRIL 01, 2020
Purpose: To evaluate the evolution of osteoarthritis rat knees second histological evaluation of OARSI (Osteoarthritis Research Society International) after undernatured collagen oral supplementation.
Methods: 24 rats were divided into 4 groups: Control (C), Osteoarthritis (OA), Control with Supplementation (CS) and Osteoarthritis with Supplementation (OS). The OA and OAS groups had bilateral anterior cruciate ligament transection (ACLT) as animal model of osteoarthritis. After 2 weeks of surgery, groups CS and OAS started the oral supplementation protocol of 5mg of undenatured collagen diluted in 1 ml of water daily for 2 weeks. At the end of the experiment, the knee joints of all rats were collected, processed in paraffin, and some histological sections,were stained with Hematoxylin and Eosin for histological evaluation according to OARSI recommendations (Gerwin et al., 2010).
We evaluated 9 items: Cartilage matrix loss width, Cartilage degeneration score, Total cartilage degeneration width, Significant cartilage degeneration width, Zonal depth ratio of lesions, Osteophytes, Calcified cartilage and subchondral bone damage, Synovial reaction and Medial joint capsule repair.
Results: The changes in the loss of extracellular matrix (ECM) occurred only at 0% depth (superficial region) however, at 50% depth (intermediate region) and 100% depth (deep region) (Table 1).In the cartilage degeneration score, only the OA group obtained significant score, showing a difference between all groups (p = 0.001) (Table 2). In the evaluation of the synovial membrane, the OA group presented difference between all groups (OA and C, p = 0.04; OA and CS, p = 0.04; OA and OAS, p = 0.04). The OAS group showed difference between all groups (OAS and C, p = 0.04; OAS and CS, p = 0.04; OAS and OA, p = 0.04) (Figure 1).The measurement of lesion depth by zone again showed no difference between groups. In the morphometric evaluation of the osteophytes, the groups C, CS, OAS and OA did not present osteophytes larger than 200 μm, therefore, by the OARSI tool they are considered marginal and score 0.The joint capsule evaluation showed a small increase of the joint capsule thickness of the OA group, but the groups showed no difference between them.
Conclusions: The oral supplementation with collagen had great findings only in the initial alterations of the OA, especially the remodeling of the synovial membrane and the superficial layer of the cartilage. Our collagen supplementation protocol showed that the collagen supplementation brought benefits to the studied tissues demonstrating a great potential of the drug for the treatment of osteoarthritis onset.