Calcium overload and reactive oxygen species accumulation induced by selenium deficiency promote autophagy in swine small intestine

Abstract

Selenium (Se) deficiency can seriously affect the small intestine of swine, and cause diarrhea in swine. However, the specific mechanism of Se deficiency-induced swine diarrhea has rarely been reported. Here, to explore the damage of Se deficiency on the calcium homeostasis and autophagy mechanism of swine, in vivo and in vitro models of swine intestinal Se deficiency were established. Twenty-four pure line castrated male Yorkshire pigs (45 d old, 12.50 ± 1.32 kg, 12 full-sibling pairs) were divided into 2 equal groups and fed Se-deficient diet (0.007 mg Se/kg) as the Se-deficiency group, or fed Se-adequate diet (0.3 mg Se/kg) as the control group for 16 weeks. The intestinal porcine enterocyte cell line (IPEC-J2) was divided into 2 groups, and cultured by Se-deficient medium as the Se-deficient group, or cultured by normal medium as the control group. Morphological observations showed that compared with the control group, intestinal cells in the Se-deficiency group were significantly damaged, and autophagosomes increased. Autophagy staining and cytoplasmic calcium staining results showed that in the Se-deficiency group, autophagy increased and calcium homeostasis was destroyed. According to the reactive oxygen species (ROS) staining results, the percentage of ROS in the Se-deficiency group was higher than that in the control group in the in vitro model. Compared with the control group, the protein and mRNA expressions of autophagy-calcium-related genes including Beclin 1 , microtubule-associated proteins 1A ( LC3-1 ), microtubule-associated proteins 1B ( LC3-2 ), autophagy-related protein 5 ( ATG5 ), autophagy-related protein 12 ( ATG12 ), autophagy-related protein 16 ( ATG16 ), mammalian target of rapamycin ( mTOR ), calmodulin-dependent protein kinase kinase β ( CAMKK-β ), adenosine 5′-monophosphate-activated protein kinase ( AMPK ), sarco(endo)plasmic reticulum Ca 2+ -ATPase ( SERCA ), and calpain in the Se-deficiency group were significantly increased which was consistent in vivo and in vitro ( P < 0.05). Altogether, our results indicated that Se deficiency could destroy the calcium homeostasis of the swine small intestine to trigger cell autophagy and oxidative stress, which was helpful to explain the mechanism of Se deficiency-induced diarrhea in swine.

Decreased thioredoxin reductase 3 expression promotes nickel‐induced damage to cardiac tissue via activating oxidative stress‐induced apoptosis and inflammation

“…Oxidative stress is the major cause of mitochondrial apoptosis, autophagy, and chronic inflammation, 81–84 but the crosstalk between the three is very complex, and either cooperating or antagonizing each other about cell function is possible 85 . Our study confirmed that apoptosis and autophagy acted synergistically in pro‐death and elicited increased pro‐inflammatory factors in mouse heart tissue under the same stimulation conditions (Ni exposure).…”

Protective Effects of Astilbin Against Cadmium-Induced Apoptosis in Chicken Kidneys via Endoplasmic Reticulum Stress Signaling Pathway

“…Immunoblotting was carried out by blocking the membranes in 5% non-fat milk for 2 h and hatched with diluted primary antibody against GRP78, PERK, Bax, caspase-12, caspase-9, caspase-3, and Bcl-2 (Wanleibio Co., Ltd., Shenyang, China) and β-actin (1:1000, Beijing Zhong Shan-Golden Bridge Biological Technology Co., Ltd., Beijing, China) overnight [42]. Then, the members were incubated with HorseRadish Peroxidase (HRP)-conjugated immunoglobin G (IgG) (1:5000, Bioss Co., Ltd., Beijing, China).…”

Molybdenum and Cadmium Co-induce Mitochondrial Quality Control Disorder via FUNDC1-Mediated Mitophagy in Sheep Kidney

“…The specific experimental method of RT-QPCR was referred to a previous study (32). TRIzol reagent (Vazyme Biotech, China) was used to segregate total RNA from kidney tissue following the explanations supplied by the manufacturer.…”