Effects of Blueberry and Collard Greens Dietary Intervention on Metabolic and Inflammatory Biomarkers in Zucker Obese Rats

Background/Objectives: Obesity is a global health challenge associated with metabolic and inflammatory health outcomes. Dietary interventions such as phytochemical-rich foods may offer a sustainable and cost-effective approach to improving health outcomes associated with obesity. This study evaluated the effects of diets containing 4% blueberry powder and extracts, and 4% collard greens powder and extracts, and a combination of 2% blueberry and 2% collard greens on metabolic and inflammatory biomarkers in obese Zucker rats. Methods: Fifty-six male rats were randomly assigned to seven treatment groups (n = 8), including five diet treatment groups, an AIN- 93 control group, and an Ozempic® (semaglutide)-treated group. Body weight, feed intake, plasma glucose, lipid profile, and inflammatory biomarkers were assessed following an 8-week dietary intervention. Results: A high mortality rate was observed in the Ozempic® (semaglutide)-treated group, with five out of eight rats dying during the third week of intervention. The semaglutide-treated group showed the greatest reductions in fasting plasma glucose concentrations. Diets supplemented with blueberry and collard greens significantly increased HDL cholesterol and reduced LDL cholesterol concentrations compared with the control group, while also improving selected inflammatory biomarkers. The collard green extract group had the lowest IL-6 concentration (34.65 ± 3.90 pg/mL) compared with the control group (339.57 ± 185.65 pg/mL) (p < 0.05). Conclusions: Overall, blueberries and collard greens consumption improved dyslipidemia and inflammation in obese Zucker rats. These preliminary findings suggest that phytochemical-rich fruits and vegetables may provide a cost-effective dietary strategy for improving metabolic and inflammatory outcomes associated with obesity.