Endogenous Hydrogen Sulfide Promotes Apoptosis via Mitochondrial Pathways in the Livers of Broilers with Selenium Deficiency Exudative Diathesis Disease

Hydrogen sulfide ameliorates abdominal aorta coarctation-induced myocardial fibrosis by inhibiting pyroptosis through regulating eukaryotic translation initiation factor 2α phosphorylation and activating PI3K/AKT1 pathway

This study aimed to assess the effects of exogenous hydrogen sulfide (H2S) on abdominal aorta coarctation (AAC) induced myocardial fibrosis (MF) and autophagy in rats. Forty-four Sprague-Dawley rats were randomly divided into control group, AAC group, AAC + H2S group, and H2S control group. After a model of rats with AAC was built surgically, AAC + H2S group and H2S group were injected intraperitoneally with H2S (100 μmol/kg) daily. The rats in the control group and the AAC group were injected with the same amount of PBS. We observed that H2S can improve left ventricular function and the deposition of myocardial collagen fibers, inhibit pyroptosis, down-regulate the expression of P-eif2α in myocardial tissue, and inhibit cell autophagy by activating the phosphatidylinositol 3-kinase (PI3K)/AKT1 signaling pathway (p < 0.05). In addition, angiotensin II (1 μM) H9c2 cardiomyocytes were injured in vitro experiments, and it was also observed that pyroptosis was inhibited after H2S (400 μmol/kg) intervention, the expression of P-eif2α in cardiomyocytes was significantly down-regulated, and the PI3K/AKT1 signaling pathway was activated at the same time. Therefore, increasing the expression of P-eif2α reverses the activation of the PI3K/AKT1 signaling pathway by H2S. In conclusion, these findings suggest that exogenous H2S can ameliorate MF in rats with AAC by inhibiting pyroptosis, and the mechanism may be associated with inhibiting the phosphorylation of eif2α and activating the PI3K/AKT1 signaling pathway to inhibit excessive cell autophagy.

Development and validation of a selenium metabolism regulators associated prognostic model for hepatocellular carcinoma

BACKGROUND

Selenium metabolism has been implicated in human health. This study aimed to identify a selenium metabolism regulator-based prognostic signature for hepatocellular carcinoma (HCC) and validate the role of INMT in HCC.

METHODS

Transcriptome sequencing data and clinical information related to selenium metabolism regulators in TCGA liver cancer dataset were analysed. Next, a selenium metabolism model was constructed by multiple machine learning algorithms, including univariate, least absolute shrinkage and selection operator, and multivariate Cox regression analyses. Then, the potential of this model for predicting the immune landscape of different risk groups was evaluated. Finally, INMT expression was examined in different datasets. After knockdown of INMT, cell proliferation and colony formation assays were conducted.

RESULTS

A selenium metabolism model containing INMT and SEPSECS was established and shown to be an independent predictor of prognosis. The survival time of low-risk patients was significantly longer than that of high-risk patients. These two groups had different immune environments. In different datasets, including TCGA, GEO, and our PUMCH dataset, INMT was significantly downregulated in HCC tissues. Moreover, knockdown of INMT significantly promoted HCC cell proliferation.

CONCLUSIONS

The current study established a risk signature of selenium metabolism regulators for predicting the prognosis of HCC patients. INMT was identified as a biomarker for poor prognosis of HCC.

Role of 3-Mercaptopyruvate Sulfurtransferase (3-MST) in Physiology and Disease

3-mercaptopyruvate sulfurtransferase (3-MST) plays the important role of producing hydrogen sulfide. Conserved from bacteria to Mammalia, this enzyme is localized in mitochondria as well as the cytoplasm. 3-MST mediates the reaction of 3-mercaptopyruvate with dihydrolipoic acid and thioredoxin to produce hydrogen sulfide. Hydrogen sulfide is also produced through cystathionine beta-synthase and cystathionine gamma-lyase, along with 3-MST, and is known to alleviate a variety of illnesses such as cancer, heart disease, and neurological conditions. The importance of cystathionine beta-synthase and cystathionine gamma-lyase in hydrogen sulfide biogenesis is well-described, but documentation of the 3-MST pathway is limited. This account compiles the current state of knowledge about the role of 3-MST in physiology and pathology. Attempts at targeting the 3-MST pathway for therapeutic benefit are discussed, highlighting the potential of 3-MST as a therapeutic target.

Roles of selenoprotein K in oxidative stress and endoplasmic reticulum stress under selenium deficiency in chicken liver

Selenoprotein K (SELENOK) is a major part of selenoprotein family. Selenoproteins have been proven playing vital roles in a variety of physiological processes. However, as a necessary supplement to the body of trace elements, how SELENOK regulates necroptosis in chicken liver has none clear claim. The purpose of this study was to cover the mechanism of SELENOK act in necroptosis of chicken liver. By feeding Se-deficiency diet for 1-day-old hyline chickens, we successfully built SELENOK-deficiency and discussed the regulation SELENOK have done. The test of liver function showed there has dysfunction appeared in the -Se groups. Results of TEM showed necroptosis occurred in the 35-Se group. After that western blot and qRT-PCR results prompted us SELENOK-deficiency caused large accumulation of ROS, enhanced endoplasmic reticulum stress, abnormally elevated HSPs family expression, and activated RIPK1-RIPK3 complex. In order to show the regulation of SELENOK in chicken liver, we artificially knocked off SELENOK gene in LMH cells. Through AO/EB staining we also found necroptosis in the siRNA-Se group. Furthermore, the results in LMH cells were coincided with those in chicken (Gallus gallus) liver. Our experiment clarified the molecular mechanism of SELENOK in the regulation and liver necroptosis, and provided reference for the healthy feeding mode of broilers.

MiR-1656 targets GPX4 to trigger pyroptosis in broilers kidney tissues by activating NLRP3 inflammasome under Se deficiency

Selenium (Se) is a vital minor element for the organism. Se deficiency caused inflammation in kidney tissue and regulate the expression of selenoproteins and microRNAs (miRNAs). Pyroptosis involved in the inflammatory response, however, whether microRNA targets GPX4 to regulate Se-deficient kidney tissue pyroptosis is unclear. In this study, broilers were divided into two groups, Control group with 0.3mg/kg Se diet and Se-deficient group with 0.03mg/kg Se diet. The dual luciferase reporter assay system and quantitative real-time PCR (qRT-PCR) were used to screen the specificity of miR-1656 and its target protein in Se-deficient broilers. We tested the pyroptosis-related genes of Se-deficient broilers kidney and miR-1656-transfected primary broilers kidney by qRT-PCR, Western blot (WB) and immunofluorescence staining. Our research indicated that the GPX4 is one of the target genes of miR-1656, and Se deficiency leaded to the overexpression of miR-1656 and the increased expression of pyroptosis-related genes. The overexpression of miR-1656 can induce increased expression of pyroptosis-related genes including NLRP3, Caspase-1, IL-18, and IL-1β by inhibiting the release of GPX4. This study showed that miR-1656 could increase the release of ROS by targeting GPX4, activated the NLRP3 inflammasome, and release the inflammatory factors IL-1β and IL-18 to trigger pyroptosis in the kidney tissue of Se-deficient broilers. This finding may provide new research ideas for kidney injury and cell death due to Se deficiency.

The Role of Selenium in Pathologies: An Updated Review

Selenium is an essential microelement required for a number of biological functions. Selenium—and more specifically the amino acid selenocysteine—is present in at least 25 human selenoproteins involved in a wide variety of essential biological functions, ranging from the regulation of reactive oxygen species (ROS) concentration to the biosynthesis of hormones. These processes also play a central role in preventing and modulating the clinical outcome of several diseases, including cancer, diabetes, Alzheimer’s disease, mental disorders, cardiovascular disorders, fertility impairments, inflammation, and infections (including SARS-CoV-2). Over the past years, a number of studies focusing on the relationship between selenium and such pathologies have been reported. Generally, an adequate selenium nutritional state—and in some cases selenium supplementation—have been related to improved prognostic outcome and reduced risk of developing several diseases. On the other hand, supra-nutritional levels might have adverse effects. The results of recent studies focusing on these topics are summarized and discussed in this review, with particular emphasis on advances achieved in the last decade.

miR-130-CYLD Axis Is Involved in the Necroptosis and Inflammation Induced by Selenium Deficiency in Pig Cerebellum

Selenium (Se) is an essential trace element in creatures which deficiency can cause necroptosis and inflammation of multiple tissues. MicroRNAs (miRNAs) have been identified to participate multiple biological processes by regulating the expression of target genes. In the present study, the Se-deficient pig cerebellar model was established and conducted by light microscopy, qRT-PCR, and Western blot. Morphological observation exhibited necrosis-like lesions and inflammatory infiltration in the cerebellum of the Se-deficient group. Quantitative analysis result showed that Se deficiency significantly suppressed miR-130 expression, which in turn disinhibited the expression of CYLD. Meanwhile, in comparison to the control group, the expression levels of TNF-α pathway genes (TNF-α, TNFR1, and NF-κB p65) and necroptosis-related genes (RIPK1, RIPK3, and MLKL) in Se deficiency group were obviously increased (P < 0.05). Moreover, Se deficiency induced the occurrence of inflammation by upregulating the expression of inflammatory cytokines (IL-1β, IL-2, IL-8, IL-18, IFN-γ, COX-2, PTGEs, and NLRP3). In conclusion, we proved Se deficiency could induce the deregulation of miR-130-CYLD axis to cause RIPK3-dependent necroptosis and inflammation in pig cerebellum.

Evaluation of the safety and nutritional equivalency of maize grain with genetically modified event DP-Ø23211-2

Feeding studies were conducted with rats and broiler chickens to assess the safety and nutrition of maize grain containing event DP-Ø23211-2 (DP23211), a newly developed trait-pyramid product for corn rootworm management. Diets containing 50% ground maize grain from DP23211, non-transgenic control, or non-transgenic reference hybrids (P0928, P0993, and P1105) were fed to Crl:CD®(SD) rats for 90 days. Ross 708 broilers were fed phase diets containing up to 67% maize grain from each source for 42 days. Body weight, gain, and feed conversion were determined for comparisons between animals fed DP23211 and control diets in each study. Additional measures included clinical and neurobehavioral evaluations, ophthalmology, clinical pathology, organ weights, and gross and microscopic pathology for rats, and carcass parts and select organ yields for broilers. Reference groups were included to determine if any observed significant differences between DP23211 and control groups were likely due to natural variation. No diet-related effects on mortality or evaluation measures were observed between animal fed diets produced with DP23211 maize grain and animal fed diets produced with control maize grain. These studies show that maize grain containing event DP-Ø23211-2 is as safe and nutritious as non-transgenic maize grains when fed in nutritionally adequate diets. The results are consistent with previously published studies, providing further demonstration of the absence of hazards from edible-fraction consumption of genetically modified plants.

Exogenous Hydrogen Sulfide Ameliorates Diabetic Myocardial Fibrosis by Inhibiting Cell Aging Through SIRT6/AMPK Autophagy

Stress aging of myocardial cells participates in the mechanism of myocardial fibrosis (MF). Previous studies have shown that hydrogen sulfide (H₂S) can improve MF, however the specific internal mechanism remains still unclear. Therefore, this study aims to explore whether H₂S can improve myocardial cell aging induced by high glucose and myocardial fibrosis in diabetic rats by activating autophagy through SIRT6/AMPK. We observed that HG (high glucose, 33 mM) induced down-regulation of endogenous H₂S-producing enzyme CSE protein expression, increased cell senescence, down-regulation of autophagy-related proteins Beclin1, Atg5, Atg12, Atg16L1, and inhibition of SIRT6/AMPK signaling pathway in H9c2 cardiomyocytes. H₂S (NaHS: 400 μM) could up-regulate CSE protein expression, inhibit cell senescence, activate autophagy and SIRT6/AMPK signaling pathway. On the contrary, no above phenomena was achieved upon addition of CSE inhibitor PAG (dl-propargylglycine: mmol/L). In order to further elucidate the relationship between H₂S and SIRT6/AMPK signaling pathway, dorsomorphin dihydrochloride (Dor), an inhibitor of AMPK signaling pathway, was added to observe the reversal of H₂S’s inhibitory effect on myocardial cell aging. At the same, streptozotocin (STZ; 40 mg/kg) was injected intraperitoneally to build an animal model of diabetic SD rats. The results showed that myocardial collagen fibers were significantly deposited, myocardial tissue senescent cells were significantly increased and the expression of CSE protein was down-regulated, while SIRT6/AMPK signaling pathway and cell autophagy were significantly inhibited. H₂S-treated (NaHS; 56 μmol/kg) could significantly reverse the above phenomenon. In conclusion, these findings suggest that exogenous H₂S can inhibit myocardial cell senescence and improve diabetic myocardial fibrosis by activating CSE and autophagy through SIRT6/AMPK signaling pathway.

The role of necroptosis and apoptosis through the oxidative stress pathway in the liver of selenium-deficient swine

Necroptosis is regarded as a new paradigm of cell death that plays a key role in the liver damage observed with selenium (Se) deficiency.

Pharmacokinetics of Sodium Selenite Administered Orally in Blood and Tissues of Selenium-Deficient Ducklings

Selenium (Se) is an essential trace element for humans and animals. Appropriate amount of Se in the body can prevent a variety of diseases. However, Se deficiency leads to pathological changes such as skeletal muscle necrosis and pancreatic atrophy in livestock and poultry. Se preparations are widely used in the prevention and treatment of Se-deficient disease, but there is no unified standard of medication, and the safe dose range of Se is narrow. Therefore, it is of great significance to study the pharmacokinetics of low-Se ducklings and to formulate drug administration schemes. In the present study, eighty 1-day-old healthy ducklings were randomly selected, and fed with low-Se diet to 30 days of age (blood Se content ≦ 0.03 μg/mL). After the low Se duckling models were duplicated, blood samples and tissues of livers, pancreases, and thigh muscles were collected at different time points to detect Se content following oral administration of 0.1% sodium selenite (Na₂SeO₃) at 0.8 mg/kg BW, and the pharmacokinetics parameters were automatically calculated by MCPKP program. The results showed that pharmacokinetics characteristics of Na₂SeO₃ in blood, livers, and pancreases of ducklings were consistent with the first-order absorption and two-compartment open models; in thigh muscles was consistent with the first-order absorption and one compartment with a lag time open model. The primary kinetic parameters of Na₂SeO₃ in blood: the half-life of absorption was 5.9026 h, the time of reaching maximum concentration was 23.03 h, and the half-life of elimination was 131.13 h. The absorption of Na₂SeO₃ in livers was the quickest, pancreases and thigh muscles were in order of becoming slower, and the elimination of Na₂SeO₃ in thigh muscles was the quickest, livers and pancreases were in order of becoming slower. The administration parameters of multi-dose were calculated according to the kinetic of single-dose: loading dose (D*) was 1.7046 mg/kg BW, maintenance dose (D₀) was 0.8 mg/kg BW, and dosing interval (τ) was 120 h. The results of this study can supplement and improve the theoretical system of Se metabolic kinetics, and provide experimental basis for the prevention and treatment of Se deficiency disease by rational drug use.