Dietary Selenium Deficiency Exacerbates Lipopolysaccharide-Induced Inflammatory Response in Mouse Mastitis Models

BPA exposure and Se deficiency caused spleen damage in chickens by nitrification stress-TNF-α

With the increasing production and demand of plastic products in life, inescapable bisphenol A (BPA) exposure results in a threat to the health of organisms. Selenium (Se) is an essential trace element for living organisms. The insufficient Se intake can cause multi-tissue organ damage. In the process of production and life, the exposure of BPA is usually accompanied by Se deficiency. In this study, the models of chicken with BPA exposure and/or Se deficiency was duplicated, the status of nitrification stress, apoptosis, necroptosis, and changes in TNF-α/FADD signaling pathways in chicken spleen were examined. At the same time, nitrification stress inhibitor and TNF-α inhibitor were introduced into MSB-1 cell model tests in vitro, indicating that BPA exposure and Se deficiency up-regulated TNF-α/FADD signaling pathway through nitrification stress, inducing necroptosis and apoptosis, and heat shock protein was also involved in this process. This study provides a new control idea for healthy poultry breeding based on Se, and also provides a new reference for toxicity control of environmental pollutants.

The mechanism of selenium regulating the permeability of vascular endothelial cells through selenoprotein O

Vascular diseases, a leading cause of death in human, are strongly associated with pathological damage to blood vessels. The selenoprotein (Sel) have been reported to play important roles in vascular disease. However, the role of SelO in vascular disease has not been conclusively investigated. The present experiment was to investigate the regulatory mechanism of the effect of SelO on the permeability of vascular endothelial. The H.E staining, FITC-Dextran staining, Dil-AC-LDL staining and FITC-WGA staining showed that vascular structure was damaged, and intercellular junctions were disrupted with selenium (Se)-deficient. Immunohistochemistry, qPCR and Western blot revealed decreased expression of the adhesion plaque proteins vinculin, talin and paxillin, decreased expression of the vascular connectivity effector molecules connexin, claudin-1 and E-cadherin and increased expression of JAM-A and N-cadherin, as well as decreased expression of the ZO-1 signaling pathways ZO-1, Rock, rhoGEF, cingulin and MLC-2. In a screening of 24 Sel present in mice, SelO showed the most pronounced changes in vascular tissues, and a possible association between SelO and vascular intercellular junction effectors was determined using IBM SPSS Statistics 25. Silencing of SelO, vascular endothelial intercellular junction adverse effects present. The regulatory relationship between SelO and vascular endothelial intercellular junctions was determined. The results showed that Se deficiency lead to increased vascular endothelial permeability and vascular tissue damage by decreasing SelO expression, suggesting a possible role for SelO in regulating vascular endothelial permeability.

Selenium Prevents Inflammation in Human Placenta and Adipose Tissue In Vitro: Implications for Metabolic Diseases of Pregnancy Associated with Inflammation

Gestational diabetes mellitus (GDM) and maternal obesity are significant metabolic complications increasingly prevalent in pregnancy. Of major concern, both GDM and maternal obesity can have long-term detrimental impacts on the health of both mother and offspring. Recent research has shown that increased inflammation and oxidative stress are two features central to the pathophysiology of these metabolic conditions. Evidence suggests selenium supplementation may be linked to disease prevention in pregnancy; however, the specific effects of selenium on inflammation and oxidative stress associated with GDM and maternal obesity are unknown. Therefore, this study aimed to investigate the effect of selenium supplementation on an in vitro model of GDM and maternal obesity. Human placental tissue, visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were stimulated with either the bacterial product lipopolysaccharide (LPS) or the pro-inflammatory cytokine TNF-α. Selenium pre-treatment blocked LPS and TNF-α induced mRNA expression and secretion of pro-inflammatory cytokines and chemokines, while increasing anti-inflammatory cytokine and antioxidant mRNA expression in placenta, VAT and SAT. Selenium pre-treatment was also found to inhibit LPS- and TNF-α induced phosphorylation of ERK in placenta, VAT and SAT. These findings indicate that selenium may be able to prevent inflammation and oxidative stress associated with GDM and maternal obesity. Additional in vivo studies are required to identify the efficacy of selenium supplementation in preventing inflammatory pathways activated by GDM and maternal obesity and to elucidate the mechanism involved.

In vitro selenium supplementation suppresses key mediators involved in myometrial activation and rupture of fetal membranes

Spontaneous preterm birth, which can affect up to 20% of all pregnancies, is the greatest contributor to perinatal morbidity and mortality. Infection is the leading pathological cause of spontaneous preterm birth. Infection activates the maternal immune system, resulting in the upregulation of pro-inflammatory and pro-labor mediators that activate myometrial contractions and rupture of fetal membranes. Anti-inflammatory agents therefore have the potential for the prevention of spontaneous preterm birth. Selenium, an essential micronutrient, has been shown to be a potent anti-inflammatory regulator. Notably, clinical and epidemiological studies have suggested a link between selenium and preterm birth. Thus, the aim of this study was to assess the effect of selenite (an inorganic form of selenium) on the expression of pro-inflammatory and pro-labor mediators in human gestational tissues. Human fetal membranes and myometrium were pre-incubated with or without selenite before incubation with the bacterial product lipopolysaccharide (LPS) to stimulate inflammation associated with preterm birth. Selenite blocked LPS-induced expression of pro-inflammatory cytokines and chemokines and enzymes involved in remodelling of myometrium and degradation of fetal membranes. Of note, selenite also suppressed myometrial activation induced by inflammation as evidenced by a decrease in LPS-induced prostaglandin signalling and myometrial cell contractility. These effects of selenite were mediated by the MAPK protein ERK as selenite blunted LPS induced activation of ERK. In conclusion, selenite suppresses key mediators involved in inflammation induced activation of mediators involved in active labor in human fetal membranes and myometrium. These findings support recent clinical studies demonstrating selenium supplementation is associated with decreased incidence of spontaneous preterm birth.

Hepatic-Specific Decrease in the Expression of Selenoenzymes and Factors Essential for Selenium Processing After Endotoxemia

Background

Selenium (Se) levels decrease in the circulation during acute inflammatory states and sepsis, and are inversely associated with morbidity and mortality. A more specific understanding of where selenoproteins and Se processing are compromised during insult is needed. We investigated the acute signaling response in selenoenzymes and Se processing machinery in multiple organs after innate immune activation in response to systemic lipopolysaccharide (LPS).

Methods

Wild type (WT) adult male C57/B6 mice were exposed to LPS (5 mg/kg, intraperitoneal). Blood, liver, lung, kidney and spleen were collected from control mice as well as 2, 4, 8, and 24 h after LPS. Plasma Se concentration was determined by ICP-MS. Liver, lung, kidney and spleen were evaluated for mRNA and protein content of selenoenzymes and proteins required to process Se.

Results

After 8 h of endotoxemia, plasma levels of Se and the Se transporter protein, SELENOP were significantly decreased. Consistent with this timing, the transcription and protein content of several hepatic selenoenzymes, including SELENOP, glutathione peroxidase 1 and 4 were significantly decreased. Furthermore, hepatic transcription and protein content of factors required for the Se processing, including selenophosphate synthetase 2 (Sps2), phosphoseryl tRNA kinase (Pstk), selenocysteine synthase (SepsecS), and selenocysteine lyase (Scly) were significantly decreased. Significant LPS-induced downregulation of these key selenium processing enzymes was observed in isolated hepatocytes. In contrast to the acute and dynamic changes observed in the liver, selenoenzymes did not decrease in the lung, kidney or spleen.

Conclusion

Hepatic selenoenzyme production and Se processing factors decreased after endotoxemia. This was temporally associated with decreased circulating Se. In contrast to these active changes in the regulation of Se processing in the liver, selenoenzymes did not decrease in the lung, kidney or spleen. These findings highlight the need to further study the impact of innate immune challenges on Se processing in the liver and the impact of targeted therapeutic Se replacement strategies during innate immune challenge.

The protective effect of selenium on the lipopolysaccharide-induced oxidative stress and depressed gene expression related to milk protein synthesis in bovine mammary epithelial cells

The objective of this study was to determine the effects of selenium (Se) on antioxidative function and the synthesis of milk protein in bovine mammary epithelial cells (BMECs). Two experiments were conducted using a single-factor completely randomized design study. In part I, BMECs were randomly divided into seven groups: control (without Se) and six Se treatments (10, 20, 50, 100, 150, and 200 nmol/L). In part II, based on the results of part I, we used lipopolysaccharide (LPS) as the induced stress source to analyze the protective effect of Se on LPS-induced oxidative damage and the influence on milk protein synthesis of BMECs. BMECs were randomly divided into eight groups: control (without Se and LPS), LPS treatment (only LPS), and six Se treatments with LPS (LS10 to LS200). Treatment of BMECs with Se was found to significantly improve cell proliferation and antioxidant function. LPS could induce oxidative damage which significantly inhibited cell proliferation and antioxidant function in BMECs. Se had a protective effect on the oxidative damage of BMECs induced by LPS. Additionally, our results indicated that LPS damage downregulated the gene expression of milk protein synthesis. Se effectively relieved the inhibition due to LPS-induced oxidative damage on the synthesis of milk protein, and Se concentrations of 50 to 200 nmol/L showed the best effect. In conclusion, Se at concentrations of 50 to 100 nmol/L is better for antioxidant function but had no effect on milk protein synthesis in healthy BMECs. Se ameliorated the damage caused by LPS-induced by improving levels of antioxidant markers and upregulating milk protein synthesis and the expression of genes associated with milk protein in BMECs.

Role of Selenoproteins in Bacterial Pathogenesis

The trace element selenium is an essential micronutrient that plays an important role in maintaining homeostasis of several tissues including the immune system of mammals. The vast majority of the biological functions of selenium are mediated via selenoproteins, proteins which incorporate the selenium-containing amino acid selenocysteine. Several bacterial infections of humans and animals are associated with decreased levels of selenium in the blood and an adjunct therapy with selenium often leads to favorable outcomes. Many pathogenic bacteria are also capable of synthesizing selenocysteine suggesting that selenoproteins may have a role in bacterial physiology. Interestingly, the composition of host microbiota is also regulated by dietary selenium levels. Therefore, bacterial pathogens, microbiome, and host immune cells may be competing for a limited supply of selenium. Elucidating how selenium, in particular selenoproteins, may regulate pathogen virulence, microbiome diversity, and host immune response during a bacterial infection is critical for clinical management of infectious diseases.

Oxidative stress, inflammation, and glycometabolism disorder-induced erythrocyte hemolysis in selenium-deficient exudative diathesis broilers

Selenium (Se) deficiency causes injury of diversified tissues and cells, including livers, hearts, skeletal muscles, and erythrocytes. The aim of the present study is to explore the molecular mechanism of erythrocyte hemolysis due to Se deficiency in broilers. One hundred and eighty broilers (male/female, 1 day old) were randomly divided into two groups and fed with either a normal Se content diet (C group, 0.2 mg Se/kg) or a Se-deficient diet (ED group, 0.008 mg Se/kg) for 45 days. During the trial period of 15-30 days, biological properties such as osmotic fragility, fluidity, phospholipid components of cell membrane, adenosine triphosphatase activities, and antioxidant function of erythrocytes in broilers were examined. Moreover, the messenger RNA (mRNA) expressions of genes associated with inflammation, glycometabolism, and avian uncoupling protein (avUCP) were detected. We found that compared with the C group, hemolysis rate, degree of polarization, and microviscosity of erythrocytes were increased in broilers of the ED group. The composition of erythrocyte membrane lipids was changed. Meanwhile, the antioxidant function of erythrocytes was weakened and mRNA levels of inflammatory genes were stimulated by Se deficiency (p < 0.05). In addition, mRNA expressions of rate-limiting enzymes in glycometabolism were effected and avUCP mRNA level was downregulated (p < 0.05) in the ED group. It has been concluded from the results that oxidative stress, inflammatory response, and glycometabolism disorder lead to erythrocyte hemolysis by changing the structure and function of erythrocyte membrane in ED broilers suffered from Se deficiency.

Inflammatory Response Occurs in Veins of Broiler Chickens Treated with a Selenium Deficiency Diet

Selenium (Se) has been indicated to prevent chronic diseases including cancer, cardiovascular disease, and type 2 diabetes. However, a few studies have indicated that Se deficiency can induce vascular diseases. Thus, in the present study, we investigated the effect of Se deficiency on vascular pathology. A total of 60 male broiler chickens were randomly divided into 2 groups (n = 30). The control group (C group) was fed a basic diet, and the Se-deficient group (L group) was fed a Se-deficient, corn-soy-based diet. Changes in messenger RNA (mRNA) and protein levels of inflammatory factors and inflammation-related cytokines were examined by both RT-PCR and Western blot analysis. Our results indicate that the mRNA and protein levels of inflammatory factors and inflammation-related cytokines in the L group were significantly changed in the vein. In addition, principal component analysis (PCA) was used to define the most important parameters that could be used as key factors. The in vitro experiments also demonstrated that Se can enhance the anti-inflammatory ability of vein endothelial cells. In conclusion, Se deficiency induces an inflammatory response by modulating inflammatory factors and inflammation-related cytokines.

Lower Selenoprotein T Expression and Immune Response in the Immune Organs of Broilers with Exudative Diathesis Due to Selenium Deficiency

The objective of the present study was to investigate whether dietary selenium (Se) deficiency would affect the expression of selenoprotein T (SelT) and immune response in the immune organs of broilers. Changes in expression of inflammatory cytokines and oxidative stress response caused by Se deficiency can lead to organism damage, which in turn leads to immune response. Sixty (1-day-old) broilers were divided into the control group and Se-deficiency group. Animal models with exudative diathesis were duplicated in the broilers by feeding them Se-deficient diet for 20 days. After the Se-deficient group exhibited symptoms of exudative diathesis, all the broilers were euthanized, and their immune organs were taken for analysis. The tissues including spleen, bursa of Fabricius, and thymus were treated to determine the pathological changes (including microscopic and ultramicroscopic), the messenger RNA (mRNA) expression levels of SelT and its synthetase (SecS and SPS1), cytokine mRNA expression levels, and antioxidant status. The microscopic and ultramicroscopic analyses showed that immune tissues were obviously injured in the Se-deficient group. The mRNA expression of SelT was decreased compared with that in the control group. Meanwhile, the mRNA expression levels of SecS and SPS1 were downregulated. In the Se-deficient group, the mRNA expression levels of IL-1R and IL-1β were higher than those of three control organs. Additionally, the IL-2 and INF-γ mRNA expression levels were lower than those of the control group. The activity of CAT was decreased, and the contents of H₂O₂ and •OH were increased due to Se deficiency. Pearson method analysis showed that the expression of SelT had a positive correlation with IL-2, INF-γ, SecS, and SPS1 and a negative correlation with IL-1R and IL-1β. In summary, these data indicated that Se-deficient diet decreased the SelT expression and its regulation of oxidative stress, and it inhibited a pleiotropic mechanism of the immune response.

Oxidative stress induced by Se-deficient high-energy diet implicates neutrophil dysfunction via Nrf2 pathway suppression in swine

The mechanism of the interaction between Se deficiency and high energy remains limited. The aim of the current study was to identify whether Se-deficient, high-energy diet can induce oxidative stress, and downregulate the Nrf2 pathway and phagocytic dysfunction of neutrophils. We detected the phagocytic activity, ROS production, protein levels of Nrf2 and Nrf2 downstream target genes, and the mRNA levels of 25 selenoproteins, heat shock proteins, and cytokines in neutrophils. Cytokine ELISA kits were used to measure the serum cytokines. The concentration of ROS was elevated (P < 0.05) in obese swine fed on a low Se diet (less than 0.03 mg/kg Se) compared to control swine. The protein levels of Nrf2 and its downstream target genes were depressed during Se deficiency and high-energy intake. The mRNA levels of 16 selenoproteins were significantly decreased (P < 0.05) in the Se-deficient group and Se-deficient, high-energy group compared to the control group. However, the mRNA levels of 13 selenoproteins in peripheral blood neutrophils were upregulated in high energy group, except TrxR1, SelI and SepW. In summary, these data indicated that a Se-deficient, high-energy diet inhibits the Nrf2 pathway and its regulation of oxidative stress, and prompted a pleiotropic mechanism that suppresses phagocytosis.

Protective Action of Se-Supplement Against Acute Alcoholism Is Regulated by Selenoprotein P (SelP) in the Liver

Acute alcoholism is a major cause of cirrhosis and liver failure around the world. Selenium (Se) is an essential micronutrient promoting liver health in humans and animals. Selenoprotein P (SelP) is a glycoprotein secreted within the liver, which interacts with cytokines and the growth factor pathway to provide protection for hepatic cells. The present study was conducted to confirm the effect and mechanism of Se and SelP action in livers affected by acute alcoholism. In this study, a mouse model of acute alcoholism, as well as a hepatocyte model, was successfully established. The Se content of the liver was detected by atomic fluorescence spectrophotometry. The expression of messenger RNA (mRNA) was analyzed by quantitative polymerase chain reaction (qPCR). The protein expression of inflammatory factors was detected by ELISA. The other proteins were analyzed by western blotting. The results showed that pathological damage to the liver was gradually weakened by Se-supplementation, which was evaluated by hematoxylin and eosin (H&E) and TUNEL staining. Se-supplementation inhibited expression of pro-inflammatory factors TNF-α and IL-1β and promoted production of anti-inflammatory cytokine IL-10 in the liver with acute alcoholism. Se-supplementation also prevented the apoptosis of hepatocytes by suppressing the cleavage of caspases-9, 3, 6, 7, and poly(ADP-ribose) polymerase (PARP). Through correlational analysis, it was determined that the effects of Se-supplement were closely related to SelP expression, inflammatory cytokines, and apoptosis molecule production. The sienna of SelP further confirmed the protective action of Se-supplementation on the liver and that the mechanism of SelP involves the regulation of inflammatory cytokines and apoptosis molecules in acute alcoholism. These findings provide information regarding a new potential target for the treatment of acute alcoholism.

Selenium Deficiency-Induced Inflammation and Increased Expression of Regulating Inflammatory Cytokines in the Chicken Gastrointestinal Tract

Selenium (Se), a nutritionally essential trace element, plays an important role in various aspects of health for a wide range of species, including birds. Se deficiency inhibits the growth of immune organs and decreases immune function, leading to many inflammatory diseases. The present study determined the effects and mechanism of dietary Se deficiency on gastrointestinal tract tissue inflammation. The histopathological changes showed that Se deficiency induced inflammatory lesions in the gastrointestinal tract tissues (glandular stomach, gizzard, duodenum, small intestine, and rectum). The expression levels of PTGE (prostagland E synthase), COX-2 (cyclooxygenase-2), TNF-α (tumor necrosis factor α), and NF-κB (nuclear transfer factor κB) in the gastrointestinal tract tissues (glandular stomach, gizzard, duodenum, small intestine, and rectum) were determined by qPCR on days 15, 25, 35, 45, and 55, respectively. The results showed that Se deficiency induced high expression levels of PTGE, COX-2, TNF-α, and NF-κB in the gastrointestinal tract tissues. The effects were more obvious in the duodenum and small intestine than those in the glandular stomach, gizzard, and rectum. In addition, the expression levels of these proteins in the gastrointestinal tract tissue increased in a time-dependent manner with Se deficiency feeding time. Furthermore, Se deficiency induced the production of pro-inflammatory factors, thus aggravating inflammatory lesions in the gastrointestinal tract. The effect of Se deficiency on inflammation and other gastrointestinal tract diseases should be further studied.

Selenium Deficiency Facilitates Inflammation Following S. aureus Infection by Regulating TLR2-Related Pathways in the Mouse Mammary Gland

Selenium (Se) is an essential micronutrient affecting various aspects of health. Se deficiency has been associated with inflammation and immune responses. Mastitis poses a serious problem for humans and animals in the postpartum period. Staphylococcus aureus (S. aureus) is the most common infectious bacterial pathogen associated with mastitis. The present study sought to determine the effects and underlying mechanism of dietary Se on S. aureus-induced inflammation using a model of mouse mastitis. ELISA and Western blotting were performed to detect protein levels. Quantitative PCR (qPCR) was performed to detect messenger RNA (mRNA) levels. The histopathological changes indicated that Se deficiency resulted in increased inflammatory lesions in S. aureus mastitis, whereas Se deficiency did not induce inflammatory lesions in the mammary gland. Myeloperoxidase (MPO) activity was increased in Se-deficient mice with S. aureus mastitis. Analysis of cytokine mRNA and protein showed that Se deficiency leads to increased TNF-α, IL-1β, and IL-6 production in S. aureus mastitis. In addition, Se deficiency enhanced the mRNA and protein expressions of toll-like receptor 2 (TLR2), which were originally upregulated by S. aureus in the mammary gland tissues and human embryonic kidney 293 (HEK293)-mTLR2 cells. When Se-deficient mice were infected with S. aureus, the phosphorylation of IκB, nuclear factor-κB (NF-κB), extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 was greatly increased. The results indicate that Se deficiency could intensify the inflammatory reaction in S. aureus mastitis. This work contributes to the exploration of new methods of preventing or treating of S. aureus mastitis and other infectious diseases.

Selenium Deficiency Deteriorate the Inflammation of S. aureus Infection via Regulating NF-κB and PPAR-γ in Mammary Gland of Mice

Selenium (Se) is an essential micronutrient contributing to a strong immune system for the prevention of infections and diseases in humans and animals. Dietary Se regulates the immune status and mediates anti-inflammatory action. Mastitis is an inflammation in the mammary gland typically induced through the major pathogen S. aureus. The aim of the present study was to determine the regulating effect of Se on S. aureus-induced inflammation using a mouse mastitis model. Immunofluorescence staining was used to detect histopathological injury. ELISA was used to detect cytokine expression, while protein and mRNA levels were analyzed through Western blotting and qPCR analysis, respectively. The results showed that Se deficiency increased inflammatory lesions in individuals with S. aureus infection in the mammary gland. The NO levels showed a significant increase in Se-deficient mice with S. aureus mastitis. Se deficiency accelerated the production of pro-inflammatory factors and reduced IL-10 expression. Furthermore, the results of the present study showed that the regulating effect of Se on S. aureus-induced mastitis was associated with the NF-κB pathway. Indeed, Se deficiency suppressed PPAR-γ activity and promoted NF-κB pathway activation. Thus, Se supplementation could improve the effect on PPAR-γ and NF-κB. These results suggest that Se deficiency could aggravate the inflammatory injury resulting from S. aureus-induced mastitis. Moreover, the results of the present study contribute to the development of new prevention or treatment methods for S. aureus-induced mastitis and other infectious diseases.

Selenium Deficiency Facilitates Inflammation Through the Regulation of TLR4 and TLR4-Related Signaling Pathways in the Mice Uterus

Selenium (Se) is an essential nutritional trace element that affects the development and function of the reproductive system. Endometritis is a reproductive obstacle disease that can seriously reduce the reproductive capacity of animal. To study the effects of dietary Se deficiency on lipopolysaccharide (LPS)-induced mice endometritis, we generated a model of LPS-induced mice endometritis. The Se content in uterine tissues was detected by fluorescence spectrophotometry. The levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR). The extent of phosphorylation of IκBα, NF-κB p65, ERK, JNK, and p38 and the expression of Toll-like receptor 4 (TLR4) were detected with Western blots. The TLR4 messenger RNA (mRNA) was analyzed with qRT-PCR. The results indicated that dietary Se intake significantly influenced Se levels in uterine tissues. The Se-deficient mice model was successfully replicated, and Se deficiency exacerbated uterine tissue histopathology; increased the expression of TNF-α, IL-1β, and IL-6; facilitated the activation of TLR4; and enhanced the phosphorylation of IκBα, p65, ERK, JNK, and p38 in LPS-induced mice endometritis. Also, the effects were inhibited by a supplement of Se. In conclusion, our studies demonstrated that Se deficiency makes mice uterus more prone to inflammation. An appropriate Se supplement could enhance the immune condition of the uterus.

Effects of selenium supplementation on glucose homeostasis, inflammation, and oxidative stress in gestational diabetes: Randomized, double-blind, placebo-controlled trial

OBJECTIVE

To our knowledge, no reports are available indicating the effects of selenium supplementation on metabolic parameters, inflammatory factors, and oxidative stress in gestational diabetes mellitus (GDM). The aim of this study was to assess the effects of selenium supplementation on metabolic status in pregnant women with GDM who were not on oral hypoglycemic agents.

METHODS

This randomized, double-blind, placebo-controlled clinical trial was performed with 70 women with GDM. Patients were randomly assigned to receive either 200 μg selenium supplements as tablet (n = 35) or placebo (n = 35) for 6 wk from weeks 24 to 28 of gestation. Fasting plasma samples were taken at study baseline and after 6 wk of intervention to quantify related variables.

RESULTS

Selenium supplementation, compared with placebo, resulted in a significant reduction in fasting plasma glucose (-10.5 ± 11.9 versus +4.5 ± 12.9 mg/dL; P < 0.001), serum insulin levels (-1.98 ± 11.25 versus +5.26 ± 9.33 μIU/mL; P = 0.005), homeostasis model of assessment (HOMA)-insulin resistance (-0.84 ± 2.76 versus +1.47 ± 2.46; P < 0.001) and a significant increase in quantitative insulin sensitivity check index (+0.008 ± 0.03 versus -0.01 ± 0.01; P = 0.009). Additionally, a significant decrease in serum high-sensitivity C-reactive protein (hs-CRP) levels (-791.8 ± 2271.8 versus +500.5 ± 2563.3 ng/mL; P = 0.02) was seen after the administration of selenium supplements compared with placebo. Additionally, we observed a significant elevation in plasma glutathione (+52.14 ± 58.31 versus -39.93 ± 153.52 μmol/L; P = 0.002) and a significant reduction in plasma malondialdehyde levels (-0.01 ± 0.36 versus +0.67 ± 1.90 μmol/L; P = 0.04) after consumption of selenium supplements compared with placebo. We did not find any significant effect of taking selenium supplements on HOMA β-cell function, lipid profiles, plasma nitric oxide, or total antioxidant capacity concentrations.

CONCLUSION

Selenium supplementation in pregnant women with GDM demonstrated beneficial effects on glucose metabolism, hs-CRP levels, and biomarkers of oxidative stress.