EFFECTS OF BIOACTIVE MOLECULES ON ALVEOLAR MACROPHAGES AND GASTROINTESTINAL TRACT OF SUS SCROFA

In the last years, great importance has been given to the beneficial effects of polyphenols [1]. Agricultural by-products are a rich source of polyphenols and have a potential suitable for development into dietary supplements and various food additives [2]. The objective of the present research was to investigate gut morphology, inflammation and immune response of adult pigs (Casertana strain) fed with polyphenols extracted from olive mill wastewater added to the standard diet, by in vivo and in vitro analysis. The ‘Casertana’ pig is an ancient autochthon genetic type and represents an experimental model suitable for semi-wild controlled breeding technique. During the finishing period, pigs were randomly assigned in two groups: control group fed with a standard diet and treated group fed with standard diet supplemented with polyphenols extracted from olive mill wastewater (OMWW) using capsules (0.03 g/kg of feed per pig per day) [3]. The trial lasted for 120days. After slaughter, alveolar macrophages were extracted from pig lungs [4] and the superoxide anion assay was performed to test the anti-oxidant effects of polyphenols extracted from OMWW. Gastrointestinal tracts (stomach, duodenum, jejunum, ileum, caecum and colon) were collected from all animals, embedded in paraffin wax, serially cut in transversal sections and stained with hematoxylin– eosin for histomorphometric analysis. No significant differences in the length of the jejunum-ileum villi and the depth of the colon crypts were detected between control and polyphenols fed pigs. COX-2 immunoreactivity in the gastrointestinal tract was more intense in the control group. The low level of expression of COX-2 in immunoreactive cells in the intestine of treated pigs could suggests a protective role of polyphenols, modulating and reducing the inflammatory response [5]. Superoxide anion production in alveolar macrophages was lower in pigs fed polyphenols (p<0.05). In vitro studies suggested that OMWW polyphenols are potent antioxidants, while the interpretation of the in vivo experiments is more problematic and further studies are necessary on the interactions between bioactive feed compounds and intestinal status. [1] Zhang H, Tsao R. Dietary polyphenols, oxidative stress and antioxidant and antiinflammatory effects, Current Opinion in Food Science, 8:33-42, 2016. [2] Di Nunzio et al. Olive oil industry by-products. Effects of a polyphenol rich extract on the metabolome and response to inflammation in cultured intestinal cell, Food Research International, Volume 113, Pages 392-400, 2018. [3] Corino et al. Growth performance and oxidative status in piglets supplemented with verbascoside and teupolioside, Italian Journal of Animal Science, 6:292– 294, 2007. [4] Brockmeier et al. Coinfection of pigs with porcine respiratory coronavirus and Bordetella bronchiseptica, Veterinary Microbiology, 128:36–47, 2008. [5] Willenberg et al. Food polyphenols fail to cause a biologically relevant reduction of COX-2 activity, PLoS One, 10(10): e0139147, 2015.