Effects of Calorie restriction on formalin-induced inflammation in animal models

Avicenna Journal of Phytomedicine

Volume 5 - Number Suppl.1

Article Type: Original Article
Abstract: Objectives: Management of acute and chronic inflammation is a challenging process, and use of chemical anti-inflammatory drugs is associated with several side effects. In the perspective of the Iranian traditional medicine (ITM), there is a significant correlation between inflammation and “Imtila” (food and water accumulation in the body). Calorie restriction (CR) is defined as the reduction of food intake, which could reduce the risk of imtila and inflammation. This study aimed to investigate the effects of a 30% daily CR on the incidence of inflammation in rats in Iran. Materials and Methods: This experimental study was conducted on 18 male rats (race: Rattus rattus) weighing between 220-270 g. After inducing inflammation through formalin injection to the paws of the animals, they were randomly divided into two groups of 9 using software and prescribed with normal diet (control group) and a similar diet with 30% CR (experimental group) for eight days. Changes in the paw volume were recorded twice per day in both groups by one researchers using standard plethysmometer. In addition, serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), erythrocyte and platelet counts, white blood cell count and hemoglobin levels were compared between the study groups. Results: In this study, reduction of body weight and paw volume were more significant in the experimental group compared to the control group (p<0.001 and p=0.001, respectively). Moreover, decrease in the paw volume of the animals was more significant after day 3 of injection. Also, there were more CRP-positive rats (1 or 2+) in the control group compared to the CR group (33.3% vs. 11.1%). However, this difference was not considered to be significant (p=0.58). On the other hand, mean of ESR was significantly higher in the control group compared to the CR group (29.00±2.89 h vs. 14.00±1.55 h, respectively) (p=0.001). No significant difference was observed in other serum parameters between the two study groups. Conclusion: According to the results of this study, regression of inflammation was more significant in the animals receiving 30% CR diet compared to the control subjects.