Investigation of Vascular Endothelial Growth Factor and Endostatin Levels in Some Rat Tissues in Response to Cold Stress and Diet

Objective: Obesity, the disease of our age, is a condition that occurs when there is an excess of fat tissue in the body. It is not merely a concern about weight gain, but rather a medical issue that elevates the risk of various diseases including heart disease, diabetes, high blood pressure, and certain cancers. This study aimed to explore the impact of a high-fat diet under normal conditions and cold stress, as well as the influence of propolis as a dietary supplement, on vascular endothelial growth factor (VEGF) and endostatin levels in rats fed with propolis.  Material and Methods: Thirty-six 3-month-old female Wistar rats (6 rats in each group) sourced from Inonu University Experimental Animal Production and Research Center were utilized for the study. Propolis was administered by gavage, dissolved in water, at a dosage of 2 mL per day for two weeks. Results: The group exhibiting at least a 20% increase in weight due to high-fat diet consumption was categorized as the obese group. Tissues including heart, liver, lung, brown adipose, and white adipose tissues were procured from the obese, propolis-treated, and control groups. Endostatin and vascular endothelial growth factor levels were assessed in the tissues using the ELISA method. The study revealed an elevation in VEGF levels in brown adipose tissue in both cold stress and propolis treatment groups, accompanied by a reduction in white adipose tissue compared to the control group. Additionally, VEGF levels displayed a general increase in lung, liver, and heart tissues. Conversely, endostatin levels, an antiangiogenic factor, decreased in brown adipose tissue while increasing in white adipose tissue. In liver, lung, and heart tissues, endostatin levels exhibited a general decrease. Conclusion: The findings suggest that both cold stress and propolis treatment influence VEGF and endostatin levels in various rat tissues, indicating potential implications for obesity-related conditions and angiogenesis regulation.