AVALIAÇÃO DA SUPLEMENTAÇÃO DE Curcuma longa L. SOBRE AS ALTERAÇÕES FUNCIONAIS, INFLAMATÓRIAS E MORFOLÓGICAS DO ÍLEO EM MODELO DE ARTRITE REUMATOIDE

Abstract

Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease characterized by inflammation of the joints. In the intestines, RA changes include ulcers, vasculitis, and intestinal wall atrophy. Alternatives to the traditional treatment of RA have been studied using turmeric (Curcuma longa L.), a plant native to India and commonly used in cooking, from which curcumin is extracted, also known to be anti-inflammatory and antimicrobial. This study aimed to analyze the effects of Curcuma longa L. supplementation on the histomorphological structure of the ileum in an experimental model of rheumatoid arthritis using Complete Freund's Adjuvant (CFA). Wistar rats, with an average age of 14 weeks and an average weight of 340 g, were randomly separated into groups (n=7/group): Control (CON), Turmeric (CM), Arthritis (A), and Turmeric Arthritis (ACM). Groups A and ACM were induced to RA by injecting CFA into the base of the tail and then into the capsule of the tibiofibular joint. After 24 hours, supplementation with C. longa dry extract was started by gavage for 15 consecutive days in the CM and ACM groups at 100 mg/kg/day. The animals in all groups underwent five functional evaluations to assess joint edema and disability, grip strength, and nociception. Euthanasia was carried out on the 24th day of the experiment. The ileum was collected, and its proximal segment was processed and stained with hematoxylin-eosin for histomorphometric analysis of villus height and width, crypt depth, total thickness of the intestinal wall and tunica muscularis, and quantification of intraepithelial lymphocytes. The distal segment of the ileum was fixed and subjected to Giemsa staining for quantification and morphometric analysis of the total population of myenteric neurons. A generalized mixed model test followed by Fisher's post-test (LDS) was carried out for all the parameters analyzed (p<0.05). Body weight and perigonadal and retroperitoneal fat did not vary significantly between the groups. The induction of RA caused an increase in joint edema and paw elevation time, as well as reduced grip strength and nociception in groups A and ACM. In the ileum, the width of the villi was decreased in groups CM, A, and ACM. The other histomorphometric parameters and the quantification of intraepithelial lymphocytes were similar between the groups, as were the total density and area of the cell bodies of the myenteric neurons. The results showed that RA caused inflammation, compromising motor and nociceptive functions, which were not reversed by turmeric. Although no effects were detected in the total myenteric population, changes in the intestinal mucosa induced by RA and turmeric infer that intestinal homeostasis was influenced.