The Effectiveness of Dietary Byproduct Antioxidants on Induced CYP Genes Expression and Histological Alteration in Piglets Liver and Kidney Fed with Aflatoxin B1 and Ochratoxin A

Abstract

The purpose of this study was to investigate the potential of a byproduct mixture derived from grapeseed and sea buckthorn oil industry to mitigate the harmful damage produced by ochratoxin A and aflatoxin B1 at hepatic and renal level in piglets after weaning. Forty cross-bred TOPIGS-40 hybrid piglets after weaning were assigned to three experimental groups (E1, E2, E3) and one control group (C), and fed with experimental diets for 30 days. The basal diet was served as a control and contained normal compound feed for starter piglets without mycotoxins. The experimental groups were fed as follows: E1-basal diet plus a mixture (1:1) of two byproducts (grapeseed and sea buckthorn meal); E2-the basal diet experimentally contaminated with mycotoxins (479 ppb OTA and 62ppb AFB1); and E3-basal diet containing 5% of the mixture (1:1) of grapeseed and sea buckthorn meal and contaminated with the mix of OTA and AFB1. After 4 weeks, the animals were slaughtered, and tissue samples were taken from liver and kidney in order to perform gene expression and histological analysis. The gene expression analysis showed that when weaned piglets were fed with contaminated diet, the expression of most analyzed genes was downregulated. Among the CYP450 family, CYP1A2 was the gene with the highest downregulation. According to these results, in liver, we found that mycotoxins induced histomorphological alterations in liver and kidney and had an effect on the expression level of CYP1A2, CYP2A19, CYP2E1, and CYP3A29, but we did not detect important changes in the expression level of CY4A24, MRP2 and GSTA1 genes.

Keywords: CYPs gene expression; antioxidant effect; feed additives; mycotoxins; piglets.

Figure 1

Histopathological changes in liver of weaned piglets subjected to experimental diets. The Control group (C) showed the normal aspect of hepatocytes and sinusoids (a,b) in the H&E stain and the normal aspect of thin perilobular (c) and priportal (d) fibrous spikes in Gomori’s trichrome stain. The E1 group showed the normal aspect of the liver in the H&E stain (a,b) and Gomori’s trichrome stain (c,d). The E2 group showed dilated sinusoids and inflammatory infiltrates (arrows) and necrotic hepatocytes (*) in the H&E stain (a–c,e–g), and perilobular (d) and priportal (h) fibrosis (arrowhead) in Gomori’s trichrome stain. The E3 group displayed marked improvement of the histological aspect of the liver, which is comparable to that of the control group, in the H&E (a,b) and Gomori’s trichrome stains (c,d). Scale bar = 50 μm.

Figure 2

Histopathological changes in kidney of weaned piglets subjected to experimental diets. The Control group (C) showed the normal aspect of kidney cortex (a) and medulla (b) in the H&E stain and few collagen fibers surrounding glomeruli and tubules in cortex (c) and medulla (d) in Gomori’s trichrome stain. The E1 group showed the normal aspect of kidney cortex (a) and medulla (b) in the H&E stain and few collagen fibers surrounding glomeruli and tubules in the cortex (c) and medulla (d) in Gomori’s trichrome stain. The E2 group (a–d) kidney cortex showed glomerular atrophy (*), Bowmann’s capsule injury (arrow), inflammatory cell infiltrates (arrowhead) (a,b), or glomerular degeneration (*) in the H&E stain (a–c) and slight proliferation of peritubular collagen in Gomori’s trichrome stain (arrow) (d). (e–h) The kidney medulla showed altered tubuli (arrow), inflammatory infiltrates (arrowhead), and congestion in blood vessels in the H&E stain (e–g) and the proliferation of peritubular collagen in Gomori’s trichrome stain (arrow) (h). The E3 group displayed marked improvement of the renal histological aspect, which is comparable to that of the control group, in the kidney cortex (a) and medulla (b) in the H&E stain and in the cortex (c) and medulla (d) in Gomori’s trichrome stain. Scale bar = 50 μm.

Figure 3

Gene expression level in the liver for CYP1A2, CYP2A19, CYP2E1, CYP3A29, CYP4A24, MRP2, and GSTA1 of weaned piglets subjected to experimental diets. The data are illustrated as average values of the groups (n = 4) ± standard deviation of the mean (STDEV). Statistical significance: * p < 0.05; ** p < 0.01. The statistical significance of the changes is related to the control group level.

Figure 4

Gene expression level in the kidney for CYP1A2, CYP2A19, CYP2E1, CYP3A29, CYP4A24, MRP2, and GSTA1 of weaned piglets subjected to experimental diets. The data are illustrated as average values of the groups (n = 4) ± standard deviation of the mean (STDEV).