Hydroalcoholic extract of Brazilian green propolis modulates inflammatory process in mice submitted to a low protein diet

[Display omitted] •HGPE (hydroalcoholic green propolis extract) promotes weight gain in malnourished mice.•HGPE sustains regular serum protein levels in mice fed with low-protein diet.•HGPE reduces the inflammatory cell infiltrate into subcutaneous implants.•HGPE reduces angiogenesis regardless of nutritional status. The occurrence of inflammation and protein malnutrition is an aggravating risk factor for morbidity and mortality in the clinical setting. The green propolis, a natural product made by Apis mellifera bees from Baccharis dracunculifolia resin, has therapeutic potential to modulate chronic inflammation. However, its effect on inflammation in an impaired nutritional status is not known. The aim of this study was to characterize the effects of the administration of the hydroalcoholic extract of the green propolis in the chronic inflammatory process of mice submitted to a low-protein diet. For this, we used the subcutaneous implantation of sponge disks as an inflammatory model and the animals were distributed in the following groups: standard protein diet (12% protein content), control treatment; standard protein diet, propolis treatment; low-protein diet (3% protein content), control treatment; low-protein diet, propolis treatment. Propolis was given daily at a dose of 500 mg/kg (p.o.) during a period of 7 or 15 days. Our main findings show that animals fed with standard protein diet and treated with propolis had low levels of red blood cells, hemoglobin, and hematocrit, with the subsequent reestablishment of these levels, in addition to monocyte count elevation and higher TNF levels after one week of treatment. In the low-protein diet group, the propolis treatment provided a significant recovery in weight and maintenance of total serum protein levels at the end of two weeks of treatment. Histological analysis showed propolis reduced the inflammatory infiltrate in the sponges of both standard and low-protein diet groups. In addition, the propolis extract presented antiangiogenic effect in both groups. Therefore, our data suggests that the hydroalcoholic extract of the green propolis promotes weight recovery and avoid the reduction of protein levels, in addition to inhibit inflammation and angiogenesis in animals fed with a low-protein diet.