Brazilian Green Propolis Modulates Cholesterol Homeostasis in a Preclinical Guinea Pig Model
Authors: de Miranda Aline M. , Aldana‐Mejía Jennyfer A. , da Silva Araujo Santiago Marcella , Perobelli Juliana E. , Bastos Jairo K. 
Published: May 2022

This study investigates the effect of the hydroalcoholic extract of Brazilian green propolis on lipid metabolism in hypercholesterolemic guinea pigs. This product has been considered an important source of bioactive compounds with potential health benefits. Thirty‐six guinea pigs, Cavia porcellus (male), 90 days old, weight of 400 g, were divided into six groups of six animals each and fed a standard AIN‐93 M diet (C), hypercholesterolemic diet (H), hypercholesterolemic diet + hydroalcoholic extract (75 mg/kg body weight [HEtOH1]; 150 mg/kg body weight [HEtOH2], and 300 mg/kg body weight [HEtOH3]), or hypercholesterolemic diet + simvastatin (1.5 mg/kg body weight) (HS) for 10 weeks. The group‐specific diet and water were provided ad libitum throughout the experimental period. Blood and liver tissue samples were collected for biochemical analysis and histopathology. Statistical analysis was performed using GraphPad Prism software version 5.0. The experimental protocol for the use of animals was approved by the Ethics Committee on Animal Use of the University of São Paulo (N°18.1.999.60.0). Animals in the H groups had a lower food intake than in the C group. Fecal excretion was regulated by the administration of extracts, being higher in these groups when compared to H and HS groups. Liver weights were influenced by the diet and administration of the hydroalcoholic extract of green propolis. Hypercholesterolemic diets determined an increase of about 2 times in the relative weight of this organ when compared to the C group, being more expressive in the groups of animals that received the hydroalcoholic extract. A significant increase in serum levels of total and non‐HDL cholesterol was observed in H group, concomitant with a reduction in the concentration of cholesterol‐HDL when compared to group C. However, these high levels of total cholesterol were reduced when simvastatin and extracts were administered with the hypercholesterolemic diet. The same was observed for the non‐HDL cholesterol fraction, where administration with simvastatin and extracts significantly reduced the concentration of these fractions, especially in HS and HEtOH3 groups when compared to group H. Analysis of the HDL fraction demonstrates that the animals submitted to the hypercholesterolemic diet had the lowest levels for this parameter when compared to the groups that received the control diet and/or extracts and simvastatin. There was a significant reduction in serum triacylglycerol levels in the HEtOH2 and HEtOH3 groups. However, a change in liver metabolism was observed, favoring the deposition of lipids in the liver, a different profile from what was observed when administering simvastatin. C group presented a histological aspect compatible with the normality of the organ. The H and HS groups presented moderate to severe fat degeneration, with a slight degeneration in the HS group when compared to the H group. A profile similar to that of the HS group was observed in the HEtOH2 group. Our results suggest that the Brazilian green propolis extract induces positive effects on dyslipidemia.