Análises histológicas e imunocelulares em joelhos de ratos com osteoartrose induzida após uso de Clodronato Lipossoma

Abstract

The knee osteoarthritis is one of the most disabling diseases in the world. It presents complex pathophysiology, where a series of mechanical and inflammatory interactions promote the destruction of the joint surface, synovitis, stiffness and loss of function. The diagnosis depends of clinical and imaging signs, it is usually late and at a stage where the process has already irreversible. The aim of our study was to comparatively analyze changes in articular cartilage in the knees of rats with induced osteoarthritis that received intra-articular infiltration of liposome-coated clodronate, seeking to correlate the early structural changes in articular cartilage with the concentration of serum degradation biomarker collagen, the presence in the serum of the cytokine Interleukin 10 (IL-10) and to identify the possible beneficial and preventive effects in osteoarthritis by inactivating macrophages on the surface of the synovium. Twenty-one Wistar rats were used in the experiments, divided into 3 groups. One group, designated as control, did not receive any type of treatment, the other 2 groups induced osteoarthritis (OA) through transection of anterior cruciate ligament (TLAC). In the groups submitted to TLAC, one group (n = 7) received intraarticular knee infiltration with clodronate liposome and the other group (n = 7) received saline solution, these procedures occurred seven days before the TLAC surgical procedure. During the experiment, blood samples were collected for laboratory evaluation on the seventh day and on the twenty-first postoperative day (PO) when the animals were euthanized and material for histology was collected. The results identified that the extracellular matrix degradation biomarker was not able to identify early changes in cartilage in the time adopted for the experiment, that it was not possible to determine significant concentrations of IL-10 systemic in this period, that the technique employed in inducing osteoarthritis is adequate methodology for this type of study, and that histology has a fundamental role in the identification of the initial changes in the implantation of osteoarthritis. An important finding to be highlighted is that the use of liposome clodronate seems to have a protective effect on articular cartilage.