Role of Propolis in Reducing Inflammation and Swelling in Induced Osteoarthritis

Abstract

The aim of the study is to investigate the anti-inflammatory and swelling effects of propolis in an induced osteoarthritis (OA) in rats by using monosodium iodoacetate (MIA). The term "propolis" is from the Greek words "pro" and "polis," meaning "defense of the city," reflecting its protective role in the hive (1). This substance is composed of plant resins, such as cinnamic acid, flavonoids, albumin, terpenoids, essential oils, aromatic compounds, aromatic acids, esters, sugars, benzophenones, steroids, amino acids, and other constituents (2). It is known that propolis has flavonoids such as chrysin, apigenin, and quercetin. Flavonoids affect COX-2 mRNA level, PGE-2 expression, and activity of NF-kB as the mechanism of action on the inflammation pathway (3). Osteoarthritis is the most prevalent type of joint disease; it is a slowly progressive degenerative condition that gradually leads to structural and functional changes in the affected joints (4). Method: Twenty-four adult male rats, each weighing between 225 and 275 grams, were utilized. The experimental study took place from October 13 to November 13, 2024, at the animal facility of the College of Veterinary Medicine, University of Kufa, following a one-week acclimatization period. The animals were randomly allocated into different cages, with each cage containing six animals.

Rats were divided into four groups, with six rats in each group: group 1 (control negative), and the others were induced with osteoarthritis using monosodium iodoacetate (MIA) at a dose of 3 mg/kg intra-articular single dose. group 2 (control positive). Then two groups were treated: group 3 with propolis at a dose of 200 mg/kg and group 4 with propolis at a dose of 400 mg/kg. Treatments were given orally for 30 days. Blood was collected via cardiac puncture to obtain serum for measuring parameters such as an anti-inflammatory effect. Results: The induction of osteoarthritis in groups 2, 3, and 4 was evidenced by the inflammatory mediator's pro-inflammatory protease compounds and cytokines such as TNF-α, PGF2α, and IL-1β levels. As a result, groups 3 and 4 showed a decrease in inflammation and swelling of the joint compared to the positive control, supporting the potential of propolis as an anti-inflammatory agent in managing osteoarthritis.