Synovium-Synovial Fluid Axis in Osteoarthritis Pathology: A Key Regulator of the Cartilage Degradation Process.

Failure of conventional anti-inflammatory therapies in osteoarthritis (OA) underlines the insufficient knowledge about inflammatory mechanisms, patterns and their relationship with cartilage degradation. Considering non-linear nature of cartilage loss in OA, a better understanding of inflammatory milieu and MMP status at different stages of OA is required to design early-stage therapies or personalized disease management. For this, an investigation based on a synovium-synovial fluid (SF) axis was planned to study OA associated changes in synovium and SF along the progressive grades of OA. Gene expressions in synovial-biopsies from different grades OA patients (N = 26) revealed a peak of IL-1ß, IL-15, PGE2 and NGF in early OA (Kellgren-Lawrence (KL) grade-I and II); the highest MMP levels were found in advanced stages (KL grade-III and IV). MMPs (MMP-1, 13, 2 and 9) abundance and FALGPA activity estimated in forty SFs of progressive grades showed the maximum protein levels and activity in KL grade-II and III. In an SF challenge test, SW982 and THP1 cells were treated with progressive grade SFs to study the dynamics of MMPs modulation in inflammatory microenvironment; the test yielded a result pattern, which matched with FALGPA and the protein-levels estimation. Inflammatory mediators in SFs served as steering factor for MMP up-regulation. A correlation-matrix of IL-1ß and MMPs revealed expressional negative correlation.

Reduced synovial inflammation and inhibition of matrix metalloproteinases explicates anti-osteoarthritis activity of polyherbal formulations.

OBJECTIVES: Current osteoarthritis (OA) research experiences an incline toward Ayurveda to attain a complete cure without notable adverse effects. Ayurveda uses natural products, which are known to perform the multi-faceted role, a much demanding approach for OA management. However, lack of scientific evidence is a major drawback hindering their wider use. The present work investigated the anti-arthritic potential of Ashwagandharishta, Balarishta, Dashmoolarishta, and Triphala-extract to establish molecular-evidence for their clinical use. MATERIALS AND METHODS: Rabbit synoviocytes were induced using interleukin-1 beta (IL-1 ß) and lipopolysaccharide (LPS) separately and were further treated with study formulations to test anti-inflammatory and anti-oxidant potential, using nitric oxide (NO) and malondialdehyde (MDA) assays. Collagenase inhibition activity was estimated with N-(3-[2-Furyl] acryloyl)-Leu-Gly-Pro-Ala (FALGPA)-substrate and gelatinase spot assays. Data were analyzed with GraphPad Prism using one-way ANOVA followed by Bonferroni's multiple comparison. RESULTS: The study formulations were effective against synovitis, oxidative-stress, and inhibiting collagenase. They caused NO reduction in selected concentrations. DA showed the maximum NO decline of 0.02 ± 0 and 0.97 ± 0.62 µM/ml with IL-1 ß and LPS induction at 5 and 20 µg/ml concentrations, respectively. Estimated by FALGPA assay, increasing collagenase inhibition was observed as the function of concentration. All formulations showed a significant MDA decline, in dose-dependent manner. CONCLUSION: We assessed the anti-OA efficacy of conventionally prescribed Ayurvedic drugs using relevant biochemical assays. The studied formulations revealed potential to restrain synovitis, cartilage degeneration and to reduce oxidative stress, and the signature OA features. With established molecular authenticity, Ayurvedic drugs can offer a safer and affordable therapeutic option for OA.

Glycosaminoglycan measured from synovial fluid serves as a useful indicator for progression of Osteoarthritis and complements Kellgren-Lawrence Score.

BACKGROUND: Plain radiography is the first choice for diagnosis and monitoring of knee-osteoarthritis (OA) while, Kellgren-Lawrence score (KL) is most widely used to grade OA severity. However, incompetency for reproducibility of joint space measurement in longitudinal assessment and non-linearity of KL-score system, limits radiography-based early diagnosis of the disease. Glycosaminoglycan (GAG) is direct cartilage-degradation product, which can be measured biochemically. We strived to correlate KL-score and GAG from OA patients to compliment KL-system. METHODS: We obtained 34 synovial-fluid (SF) samples from 28 OA patients (few bilateral) with different disease severity using arthrocetesis. All patients were categorised using radiographic KL-score-system. SFs were further analysed for GAG estimation using 1,2-dimethylmethylene blue (DMMB) assay. RESULTS: A substantial increase in GAG was noted in KL-grade-II and III, comparing grade-I patients, indicating amplified cartilage-degradation. KL-grade-IV patients revealed further rise in GAG reflecting more cartilage-loss. Another category of grade-IV patients with lower GAG were also detected, indicating close to total cartilage-loss. CONCLUSIONS: Accurate diagnosis of cartilage-loss remains a challenge with OA due to limitations of KL-system; thus no target intervention is available to arrest active cartilage-loss. We propose, GAG-estimation in OA patients, characterizes accurate biochemical depiction of cartilage degeneration. GENERAL SIGNIFICANCE: Radiology often fails to reveal an accurate cartilage loss, associated with OA. GAG levels from the SFs of OA patients' serve as a useful marker, which parallels cartilage degeneration and strengthen radiographic grading system, ultimately.

Inflammatory response of cultured rat synoviocytes challenged with synovial fluid from osteoarthritis patients correlates with their radiographic grading: a pilot study.

The inflammatory nature of synovial fluid (SF) of varying grade osteoarthritis (OA) patients was estimated by measuring pro-inflammatory factors and through a unique cell-challenge experiment. SF samples were collected from six OA and one non-OA patient; spanning Kellgren-Lawrence (KL) grades were analyzed for interlukin-1-beta (IL-1ß), nitric oxide (NO) and its derivatives, and glycosaminoglycan (GAG). Levels of IL-1ß, NO, and GAG in SF did not correlate with KL grades of the patients studied. In the cell-challenge experiment, cultured rat synoviocyte fibroblasts (RSFs) were challenged by the patient's SFs with and without pre-treatment of IL-1ß and lipopolysaccharide (LPS). NO released by the cells was taken as an indicator of inflammation. SFs from KL grades 2 and 3 induced maximum inflammation in cultured RSFs (grade 2 64.61 ± 4.8 and 89.51 ± 5.6 µM/ml after 48 and 72 h, grade 3 58.27 ± 2.7 and 64.22 ± 2.8 µM/ml after 48 and 72 h, respectively). Similar trend was observed in RSF pretreated with either recombinant IL-1ß or LPS suggesting that SF from patients KL grades 2 and 3 accumulates more pro-inflammatory factors. IL-1ß-pre-treated RSFs challenged by SF for 72 h showed 234.41 ± 17.6 µM/ml increase (patient 3, grade 3), whereas higher NO after LPS pre-treatment was recorded (118.92 ± 6.2 µM/ml; patient 3, grade 3). Interestingly, SFs from grade 1 and non-OA patient could reduce released NO to 27.10 ± 2.2 µM/ml showing potency to alleviate inflammation. These interesting findings, however, need to be confirmed on a wider number of patients, which may offer significant therapeutic application in treatment of OA.