Pharmacology and Articular Cartilage Regeneration: A New Strategy for Osteoarthritis

Abstract

ABSTRACT Background: Osteoarthrosis is a slowly progressive, multifactorial, and non-inflammatory degenerative disease affecting synovial joints and is typically associated with aging or previous joint damage. Method: Fifty male Sprague Dawley rats were utilized in the study and divided into five groups, with ten rats in each group. The experiment was divided into two phases: in Phase 1, ten animals received 50 μL of saline in the left tibiotarsal joint and served as the control group (SAL), while the other four groups (n = 40) received a single dose of 50 μL complete Freund’s adjuvant (CFA) to induce monoarthritis. In Phase II, after the induction of monoarthritis, from the fourth week onward, the rats in the four CFA-induced monoarthritis groups were treated with 20 μl of gamma-amino butyric acid (GABA), serotonin (SERO), or a neurotransmitter cocktail (NTC) which were given intra-articularly once for three consecutive weeks, while one group was kept as an experimental control. The animals were monitored throughout the experiment, for ankle diameter, gait, and radiological assessment, and were then euthanized and subjected to histopathological evaluation at the conclusion of the study. Results: The study found that there were statistically significant differences in the degree of inflammation between the CFA group and the groups treated with GABA, SERO, and NTC. The CFA group exhibited the most severe and persistent inflammation, whereas the NTC group showed a milder and shorter inflammatory response than the control group (SAL). In terms of gait score, the NTC treatment resulted in a significant reduction in score compared to the treatments with GABA and SERO administered separately. The radiological scores revealed that NTC was the most effective treatment in mitigating radiographic evidence of joint damage, with a significant decrease in bone destruction. The histopathological examination showed that the NTC group had minimal tissue damage or inflammation and had a regenerative effect compared to the other treatment groups. Conclusions: In conclusion, the local administration of neurotransmitters was found to be effective in reversing inflammation, improving gait score, and mitigating radiological changes in CFA-induced arthritis in the murine model.