Influence of Nitrogen Levels on Nutrient Transporters and Regulators of Protein Synthesis in Small Intestinal Enterocytes of Piglets

Abstract

To investigate effects of dietary nitrogen level on nutrient absorption and utilization in small intestinal enterocyte of piglets, weaned piglets were fed for 10 days with diets containing 20%, 17%, or 14% crude protein (CP) with supplementation to meet requirements for essential amino acids in vivo, and IPEC-1 cells were cultured with different nitrogen levels (NL) in a culture medium (70%, 85%, and 100%) in vitro by monocultured and cocultured intestinal porcine epithelial cells (IPEC-1) and human gastric epithelial cells (GES-1). The results showed the following: (1) In animal trial, decreased dietary CP reduced transcript abundance of nutrient transporters like CAT1, PepT1, GLUT2, and SGLT-1 in jejunal mucosa (0.09 ± 0.03, P < 0.0001; 0.40 ± 0.04, P = 0.0087; 0.20 ± 0.07, P = 0.0003; 0.35 ± 0.02, P = 0.0001), but 17% CP diet did not affect jejunal protein synthesis. (2) The transcript abundance of nutrient transporters displayed similarly effective tendency in jejunal mucosa and cocultured IPEC-1 rather than that in monocultured IPEC-1. (3) Decreased nitrogen levels reduced expressive abundance of PI3K, Class 3 PI3K, TSC2, and 4E-BP1 in monocultured IPEC-1, but 85% nitrogen level did not affect expressive abundance of PI3K, TSC2, mTORC1, 4E-BP1, and S6K1 in cocultured IPEC-1. In general, decreased 3% CP or 15% nitrogen level reduced relative transcript expression of nutrient transporters, but did not affect protein synthesis in jejunal mucosa and cocultured IPEC-1. Therefore, decreased 3% dietary CP increased utilized and synthetic efficiency of nitrogen resource in small intestine and was beneficial in saving the dietary nitrogen resource.

Dietary Supplementation With Didancao (Elephantopus scaber L.) Improves Meat Quality and Intestinal Development in Jiaji Ducks

“…This result further confirmed that dietary supplementation with E. scaber increased the meat quality of ducks. The morphology of intestine is a key factor influencing nutrient absorption (25). Given the increased feed conversion in ducks fed with E. scaber, we suspected that dietary supplementation with E. scaber might improve the intestine development.…”

Effect of guanidine acetic acid on meat quality, muscle amino acids, and fatty acids in Tibetan pigs

“…The relative expressions of genes were determined by qPCR analysis using SYBR Green mix (Bio-Rad, Hercules, CA, USA) on the CFX96 Real-Time PCR Detection System (Bio-Rad Laboratories). Real-time PCR was performed in the same manner, as described previously ( 17 ). β -actin was used to normalize the mRNA expression of each target gene, and the relative expression data were calculated using the 2 −ΔΔCt method ( 17 ), where ΔΔCt = (Ct target – Ct β − actin )treatment – (Ct target − Ct β− actin )control.…”

“…Real-time PCR was performed in the same manner, as described previously ( 17 ). β -actin was used to normalize the mRNA expression of each target gene, and the relative expression data were calculated using the 2 −ΔΔCt method ( 17 ), where ΔΔCt = (Ct target – Ct β − actin )treatment – (Ct target − Ct β− actin )control. The relative expressions of adipose triglyceride lipase ( ATGL ), stearoyl CoA desaturase ( SCD ), fatty acid binding proteins ( FABP ), ankyrin 1 ( ANK 1), acetyl Co A carboxylase ( ACC ), peroxisome proliferator-activated receptor γ (PPAR γ), fatty acid synthase ( FAS ), 2, 4 -dienoyl-Co A reductase 1 ( DECR 1), sterol regulatory element binding protein ( SREBP ), and malic enzyme 1 ( ME 1) were determined.…”

Effect of Soybean Isoflavones on Proliferation and Related Gene Expression of Sow Mammary Gland Cells In Vitro

“…The detailed operation methods followed the previous literature report [ 18 ]. Briefly, 100 mg of frozen tissue was homogenized with 1 mL of RIPA Lysis Buffer (Beyotime Institute of Biotechnology, Shanghai, China) and centrifuged (16,000× g for 15 min at 4 °C) to collect the supernatants.…”