Background: The low-grade, chronic inflammation is a process characterized by slightly elevated levels of pro-inflammatory molecules. It can be induced by increased levels of saturated fatty acids which could affect toll-like receptor signaling pathways. In this experiment we estimated the degree of low-grade inflammation in different muscles of Wistar rats subjected to a high-lipid diet.Methods: To study the effect of the high-fat diet on the development of inflammation in skeletal muscles we used sixty, 8-week-old male Wistar rats. The animals were subjected to standardized rodent food – a high-fat and a standard diet. After the period of time needed to provoke inflammation we changed the diet in order to collect data for the duration of the process. We used the quantitative ELISA method to determine the degree of the tissue inflammatory process, studying the levels of pro- and anti-inflammatory marker molecules.Results: We established that the high-fat diet changes the levels of the measured proinflammatory molecules to an increase. Their levels in the studied skeletal muscles were slightly elevated compared to the controls. We detected that the inflammatory process depends on time as well. A longer period of time leads to an additional increase in the levels of the cytokines in some muscles, while their levels remain almost the same in others. The replacement of the high-lipid diet with a standard one causes the muscles to restore of their normal, non-inflammatory phenotype. At the same time, the levels of the anti-inflammatory molecule show almost no change during the experiment.Conclusions: Skeletal muscles develop inflammation as a result of the intake of a high-lipid diet. The process is low-grade, chronic and its duration is as long as the high-fat food persists in the diet of the animals. The insignificantly changed levels of the anti-inflammatory molecule indicate that the muscle tissue does not, or barely exerts control over the development of this process.
