Effects of Selenium Supplementation on Gene Expression Levels of Inflammatory Cytokines and Vascular Endothelial Growth Factor in Patients with Gestational Diabetes

The effect of selenium supplementation in pregnant women on maternal, fetal, and newborn outcomes: a systematic review and meta-analysis

OBJECTIVE

Low maternal selenium status has been associated with poor pregnancy outcomes, including preterm birth. This study aimed to evaluate available evidence of the effects of selenium supplementation during pregnancy on preterm birth and related maternal, fetal, and newborn outcomes.

DATA SOURCES

MEDLINE, Embase, CINAHL, Global Index Medicus, and the Cochrane Library were systematically searched on June 23, 2022, without language or time restrictions.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials and nonrandomized interventional studies were included if they compared the effects of selenium supplementation with placebo or no treatment among pregnant women. The review protocol was registered in the International Prospective Register of Systematic Reviews (identification number: CRD42022383669).

METHODS

For outcomes reported by ≥1 study, a meta-analysis was conducted. Because of the small number of studies and high clinical heterogeneity between populations, random-effects models were used. The Risk of Bias 2 and Risk Of Bias In Non-randomized Studies - of Interventions tools were used to assess study quality, and Grading of Recommendations Assessment, Development, and Evaluation analysis was used to determine the certainty of evidence for each outcome.

RESULTS

Literature searches identified 5105 unique records, and 32 studies met the eligibility criteria. Of note, 11 reports were not included for analysis following research integrity assessments. Moreover, 10 trials and 3 observational studies met the inclusion criteria; however, only 8 trials (1851 women) and 1 prospective cohort study (71,728 women) reported on at least 1 review outcome. Our results could not determine the effect of selenium supplementation on preterm birth at <37 weeks of gestation (relative risk, 0.65; 95% confidence interval, 0.26-1.63; very low certainty evidence) and <34 weeks of gestation (relative risk, 1.05; 95% confidence interval, 0.59-1.44; very low certainty evidence).

CONCLUSION

There is limited evidence on the effects of selenium supplementation during pregnancy. Further trials, with larger sample sizes, more representative populations, and reliable assessment of maternal selenium status at trial entry, are required.

Immunophenotyping of Monocyte Migration Markers and Therapeutic Effects of Selenium on IL-6 and IL-1β Cytokine Axes of Blood Mononuclear Cells in Preoperative and Postoperative Coronary Artery Disease Patients

Multivessel coronary artery disease (CAD) is characterized by underlying chronic vascular inflammation and occlusion in the coronary arteries, where these patients undergo coronary artery bypass grafting (CABG). Since post-cardiotomy inflammation is a well known phenomenon after CABG, attenuation of this inflammation is required to reduce perioperative morbidity and mortality. In this study, we aimed to phenotype circulating frequencies and intensities of monocyte subsets and monocyte migration markers, respectively, and to investigate the plasma level of inflammatory cytokines and chemokines between preoperative and postoperative CAD patients and later, to intervene the inflammation with sodium selenite. We found a higher amplitude of inflammation, postoperatively, in terms of CCR1high monocytes and significantly increased pro-inflammatory cytokines, IL-6, IL-8, and IL-1RA. Further, in vitro intervention with selenium displayed mitigating effects on the IL-6/STAT-3 axis of mononuclear cells derived from postoperative CAD patients. In addition, in vitro selenium intervention significantly reduced IL-1β production as well as decreased cleaved caspase-1 (p20) activity by preoperative (when stimulated) as well as postoperative CAD mononuclear cells. Though TNF-α exhibited a positive correlation with blood troponin levels in postoperative CAD patients, there was no obvious effect of selenium on the TNF-α/NF-κB axis. In conclusion, anti-inflammatory selenium might be utilized to impede systemic inflammatory cytokine axes to circumvent aggravating atherosclerosis and further damage to the autologous bypass grafts during the post-surgical period.

Evaluation of Serum Selenium and Copper Levels with Inflammatory Cytokines and Indices of Oxidative Stress in Type 2 Diabetes

Type 2 diabetes mellitus (T2DM) is a metabolic and multifactorial disease in which inflammatory markers, oxidative stress, and certain trace elements seem to have an essential role. This study investigated the relationship between serum selenium and copper level with inflammatory cytokines and oxidative stress in T2DM.In this case-control study, 30 patients with T2DM and 30 healthy individuals were selected. Serum levels of copper and selenium were measured by atomic absorption spectrometry, and TNF-α and IL-6 and oxidative stress markers were measured by ELISA. The SPSS v.22 was used for data analysis and the significance level is less than 5%.The mean age of patients was 52.9 ± 10.4 years, and the control group was 48.5 ± 10.4 years. In this study, 53.3% were female, and 46.7% were male. The levels of BMI (p = 0.002), systolic pressure (p = 0.034), insulin, selenium, malondialdehyde, and glutathione peroxidase (p = 0.0001; each), insulin resistance, copper, and superoxide dismutase, IL6, and TNF-α (p = 0.001; each) in T2DM were significantly higher than the control group. While levels of lipid profile, uric acid, creatinine, and diastolic pressure were not significantly different between the two groups. Selenium and copper are related to insulin resistance, and their increasing levels are associated with increased levels of markers of oxidative stress and inflammatory cytokines (p < 0.05).Increased levels of copper and selenium are associated with T2DM and this increase is also associated with increased levels of TNF-α, IL-6, and oxidative stress in T2DM. Therefore, controlling these markers can lead us to control this disease better.

Selenium deficiency is associated with disease severity, disrupted reward processing, and increased suicide risk in patients with Anorexia Nervosa

BACKGROUND & AIMS

Patients with Anorexia Nervosa (AN) present many nutritional deficiencies (macro- and often also micro-nutrients), possibly explained by their inadequate food intake. Previous studies reported that selenium (Se) deficiency is common in the general population. As Se can be easily added as a supplement, the goal of this study was to evaluate the clinical impact of Se deficiency in patients with AN.

METHODS

This cross-sectional study concerned 153 patients with AN (92.9% women) followed at the Eating Disorder Unit of Lapeyronie Academic Hospital, Montpellier, France. Patients underwent an extensive neuropsychological assessment, and completed validated questionnaires. Blood samples were collected for Se quantification. Results were compared with the t-test, Mann-Whitney U, and Chi square tests, and univariate linear and multivariate logistic regression models.

RESULTS

Se plasma levels were below the cut-off of 80 µg/L in 53.6% (N = 82) of patients. AN onset was earlier in patients with Se deficiency, (p = .005), whereas disease duration was comparable between groups (p = .77). General eating disorder symptomatology in the past 28 days (Eating Disorder Examination Questionnaire) was more severe in patients with Se deficiency (p = .010). The suicide risk (MINI International Neuropsychiatric Evaluation) tended to be higher (p = .037), and suicide attempt history was more frequent (28.39% vs 9.85%, p = .004) in patients with low Se levels. Se plasma concentration was negatively correlated with the performance in the temporal delayed discounting task (p = .006).

CONCLUSIONS

Our findings suggest that in patients with AN, Se plasma concentration might be implicated in disease severity and suicide risk. The finding that Se deficiency in patients with AN was associated only with reward-related processes, but not with other psychological functions suggests the selective involvement of dopamine-related pathways. Our results suggest that it might be useful to monitor the plasma micronutrient profile in patients with AN. Future studies should determine whether Se supplementation in AN might improve clinical outcomes.

Selenium Supplementation in Pregnancy-Maternal and Newborn Outcomes

Background. Several studies have suggested that increased oxidative stress during pregnancy may be associated with adverse maternal and foetal outcomes. As selenium is an essential mineral with an antioxidant role, our aim was to perform a systematic review of the existing literature reporting the effects of selenium supplementation during pregnancy on maternal and neonatal outcomes. Materials and Methods. Six electronic databases (Medline, Embase, Cochrane Library, Web of Science, Scopus, and PubMed) were searched for studies reporting the effects of selenium supplementation during pregnancy and the postpartum period on maternal and neonatal outcomes. Only randomised controlled trials on human subjects reported in English and published up to October 2021 were included. Quality assessments were conducted using the modified Downs and Black quality assessment tool. Data were extracted using a narrative synthesis. Results. Twenty-two articles were included in our systematic review (seventeen reported on maternal outcomes, two on newborn outcomes, and three on both). Maternal studies reported the effects of selenium supplementation in the prevention of thyroid dysfunction, gestational diabetes, pregnancy-induced hypertension/preeclampsia, oxidative stress, postpartum depression, premature rupture of membranes, intrauterine growth retardation, breastmilk composition, and HIV-positive women. Newborn studies reported the effects of maternal selenium supplementation on foetal oxidation stress, foetal lipid profile, neonatal hyperbilirubinemia, and newborn outcomes in HIV-positive mothers. The majority of studies were inappropriately designed to establish clinical or scientific utility. Of interest, four studies reported that selenium supplementation reduced the incidence of thyroid dysfunction and permanent hypothyroidism during the postpartum period by reducing thyroid peroxidase and thyroglobulin antibody titres. Conclusion. The evidence supporting selenium supplementation during pregnancy is poor and there is a need for appropriately designed randomised controlled trials before routine use can be recommended.

Associations of Serum Selenium Levels in the First Trimester of Pregnancy with the Risk of Gestational Diabetes Mellitus and Preterm Birth: a Preliminary Cohort Study

Women with gestational diabetes mellitus (GDM) may have lower serum selenium levels than healthy controls, which may be associated with preterm birth. We explored the association of serum selenium levels in early pregnancy with the risk of GDM and preterm birth among Chinese women. We included 398 women with a singleton pregnancy, who were followed up prospectively from the first prenatal visit until delivery. Serum selenium levels were measured in the first trimester. After delivery, data concerning mothers and their children were sourced from medical records by researchers who were blind to the participants' selenium status. Of the 398 women, 71 (17.8%) had GDM, 21(5.3%) had preterm birth, and 266 (66.8%) had selenium deficiency (serum selenium < 70 μg/L). Women in the upper three quartiles of serum selenium level did not have a significantly lower risk of GDM or preterm birth than those in the lowest quartile after adjustment for covariates (all p > 0.05). When serum selenium levels were classified as normal or deficient, the risk of GDM or preterm birth among women with normal serum selenium levels was still not lower than that of women with deficient serum selenium levels after adjustment for covariates (all p > 0.05). Although selenium deficiency was common in the Chinese women in our cohort, our results indicate that low serum selenium level during early pregnancy may not be a strong predictor of the risk of GDM and preterm birth. However, our sample size was small, and future studies with larger populations are warranted.

The Effects of Selenium Supplementation on Clinical Symptoms and Gene Expression Related to Inflammation and Vascular Endothelial Growth Factor in Infertile Women Candidate for In Vitro Fertilization

This study was performed to determine the effects of selenium supplementation on clinical symptoms and gene expression related to inflammatory markers in infertile women with polycystic ovary syndrome (PCOS) who were candidate for in vitro fertilization (IVF). Thirty-six women candidate for IVF were recruited in this randomized double-blinded, placebo-controlled trial. They (n = 18/group) were randomly assigned into intervention groups to take either 200 μg/day of selenium or placebo for 8 weeks. RT-PCR findings indicated that selenium supplementation downregulated gene expression of interleukin-1 (IL-1) (P < 0.004) and tumor necrosis factor alpha (TNF-α) (P = 0.02) in lymphocytes of patients with PCOS compared with the placebo. In addition, selenium supplementation upregulated gene expression of vascular endothelial growth factor (VEGF) (P = 0.001) in lymphocytes of patients with PCOS compared with the placebo. Selenium supplementation had no significant effect on clinical symptoms and gene expression of IL-8 (P = 0.10) and transforming growth factor beta (TGF-β) (P = 0.63). Overall, our findings documented that selenium supplementation for 8 weeks to infertile women candidate for IVF improved IL-1, TNF-α, and VEGF gene expression, though selenium had no effect on clinical symptoms and, IL-8 and TGF-β gene expression. Clinical trial registration number: http://www.irct.ir: IRCT20170513033941N23.

Effects of selenium supplementation on glucose homeostasis in women with gestational diabetes mellitus: A randomized, controlled trial

Background

There is limited evidence about the anti-diabetic effects of selenium supplementation in women with gestational diabetes mellitus (GDM).

Objective

This study investigates the effects of selenium supplementation on glucose homeostasis in women with GDM.

Materials and Methods

A total of 60 pregnant women with GDM were enrolled in this prospective randomized, double-blind, and placebo-controlled clinical trial. They were randomly assigned to take either 100µg selenium supplements as tablet or a placebo daily for 12 wk since 24-28 wk of gestation. The primary outcomes were changes in the glucose homeostasis, including fasting plasma glucose, the 2-hr post prandial blood glucose, serum insulin level, glycosylated hemoglobin (Hb A1C), and the homeostasis model assessment of insulin resistance(HOMA_IR) at the initial period and 3 months after intervention.

Results

The mean maternal age of the patients who took selenium supplements was 29.19 ± 6.16 (range 18-41) years. In the placebo group, the mean maternal age was 31 ± 4.43 (range 24-39) years. Compared with the placebo group, fasting plasma glucose, 2-hr post-prandial blood glucose, glycosylated hemoglobin(Hb A1C), serum insulin level, and homeostasis model of assessment-estimated insulin resistance(HOMA_IR) were not significantly changed in the selenium group at the end of study (p = 0.25, p = 0.87, p = 0.34, p = 0.57, and p = 0.31, respectively).

Conclusion

The results of this trial suggest that supplementation with 100µg of selenium does not modulate glucose homeostasis in women with GDM.

Manganese is associated with increased plasma interleukin-1β during pregnancy, within a mixtures analysis framework of urinary trace metals

Exposure to trace metals may impact reproductive health outcomes through perturbations in maternal immune signaling molecules. We conducted a cross-sectional study of 390 pregnant women from the LIFECODES birth cohort and investigated the associations between 17 urinary metals and five immune biomarkers measured in the 3rd trimester (median 26 weeks gestation). We used linear regression to estimate pair-wise associations and applied elastic net and Bayesian kernel machine regression to identify important contributing exposures analytes as well as non-linear effects. Maternal urinary manganese, nickel, and barium were positively associated with maternal plasma interleukin-1β (IL-1β). Elastic net and Bayesian kernel machine regression identified manganese as the dominant trace metal in association with IL-1β. An interquartile range difference in manganese (0.6 μg/L) was associated with a 29 % increase in IL-1β (95 % CI: 12.4-48.2). In conclusion, trace metal exposures were associated with biomarkers of immune perturbations, and this warrants further investigation.

Potential of Selected Trace Elements in Patients with Diabetes Mellitus

Based on the high prevalence, diabetes mellitus (DM) is considered as a worldwide problem. More than 8.3 % of the world population is suffering from this disease. One of the causing factors of this disease can be the absence or imbalance of trace, essential elements. It can cause collapses of antioxidant defence and glucose intolerance. It plays a role in the pathogenesis and progression to diabetes mellitus. This review focuses on chromium, copper, selenium, vanadium, and zinc. Many studies deal with these elements but there is variability in opinions. Insulin-mimetic activity and ability to control the concentrations of blood glucose were confirmed. However, these effects were of more importance in patients with prediabetes. In patients with prediabetes, due to the supplementation of selected trace elements, it is possible to normalize the blood glucose level and prevent the development of diabetes mellitus. The importance of supplementation was confirmed for chromium and zinc. The supplementation of vanadium has a positive effect on the normalization of glycaemia but it is necessary to control the level as it can have toxic effects during long-term treatment. Conversely, higher copper concentrations in the body adversely affect patients and chelation therapy is needed. Selenium must be kept in the standard concentration and regular control of the concentration in the body is necessary. For this reason it is necessary to continue with analysis and the creation of new methodologies that could unify the view on the issue.

To Explore the Pathogenesis of Vascular Lesion of Type 2 Diabetes Mellitus Based on the PI3K/Akt Signaling Pathway

BACKGROUND

Type 2 diabetes mellitus (T2DM) has become a chronic disease, serious harm to human health. Complications of the blood pipe are the main cause of disability and death in diabetic patients, including vascular lesions that directly affects the prognosis of patients with diabetes and survival. This study was to determine the influence of high glucose and related mechanism of vascular lesion of type 2 diabetes mellitus pathogenesis.

METHODS

In vivo aorta abdominalis of GK rats was observed with blood pressure, heart rate, hematoxylin and eosin (H&E), Masson, and Verhoeff staining. In vitro cells were cultured with 30 mM glucose for 24 h. RT-QPCR was used to detect the mRNA expression of endothelial markers PTEN, PI3K, Akt, and VEGF. Immunofluorescence staining was used to detect the expression of PTEN, PI3K, Akt, and VEGF. PI3K and Akt phosphorylation levels were detected by Western blot analysis.

RESULTS

Heart rate, systolic blood pressure, diastolic blood pressure, and mean blood pressure in the GK control group were higher compared with the Wistar control group and no difference compared with the GK experimental model group. Fluorescence intensity of VEGF, Akt, and PI3K in the high-sugar stimulus group was stronger than the control group; PTEN in the high-sugar stimulus group was weakening than the control group. VEGF, Akt, and PI3K mRNA in the high-sugar stimulus group were higher than the control group; protein expressions of VEGF, Akt, and PI3K in the high-sugar stimulus group were higher than the control group. PTEN mRNA in the high-sugar stimulus group was lower than the control group. Protein expression of PTEN in the high-sugar stimulus group was lower than the control group.

CONCLUSIONS

Angiogenesis is an important pathogenesis of T2DM vascular disease, and PTEN plays a negative regulatory role in the development of new blood vessels and can inhibit the PI3K/Akt signaling pathway.

Roles for selenium and selenoprotein P in the development, progression, and prevention of intestinal disease

Selenium (Se) is a micronutrient essential to human health, the function of which is mediated in part by incorporation into a class of proteins known as selenoproteins (SePs). As many SePs serve antioxidant functions, Se has long been postulated to protect against inflammation and cancer development in the gut by attenuating oxidative stress. Indeed, numerous studies over the years have correlated Se levels with incidence and severity of intestinal diseases such as inflammatory bowel disease (IBD) and colorectal cancer (CRC). Similar results have been obtained with the Se transport protein, selenoprotein P (SELENOP), which is decreased in the plasma of both IBD and CRC patients. While animal models further suggest that decreases in Se or SELENOP augment colitis and intestinal tumorigenesis, large-scale clinical trials have yet to show a protective effect in patient populations. In this review, we discuss the function of Se and SELENOP in intestinal diseases and how research into these mechanisms may impact patient treatment.

The Effects of Selenium Supplementation on Gene Expression Related to Insulin and Lipid in Infertile Polycystic Ovary Syndrome Women Candidate for In Vitro Fertilization: a Randomized, Double-Blind, Placebo-Controlled Trial

This study was conducted to evaluate the effects of selenium supplementation on gene expression related to insulin and lipid in infertile women with polycystic ovary syndrome (PCOS) candidate for in vitro fertilization (IVF). This randomized double-blind, placebo-controlled trial was conducted among 40 infertile women with PCOS candidate for IVF. Subjects were randomly allocated into two groups to intake either 200-μg selenium (n = 20) or placebo (n = 20) per day for 8 weeks. Gene expression levels related to insulin and lipid were quantified in lymphocytes of women with PCOS candidate for IVF with RT-PCR method. Results of RT-PCR demonstrated that after the 8-week intervention, compared with the placebo, selenium supplementation upregulated gene expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) (1.06 ± 0.15-fold increase vs. 0.94 ± 0.18-fold reduction, P = 0.02) and glucose transporter 1 (GLUT-1) (1.07 ± 0.20-fold increase vs. 0.87 ± 0.18-fold reduction, P = 0.003) in lymphocytes of women with PCOS candidate for IVF. In addition, compared with the placebo, selenium supplementation downregulated gene expression of low-density lipoprotein receptor (LDLR) (0.88 ± 0.17-fold reduction vs. 1.05 ± 0.22-fold increase, P = 0.01) in lymphocytes of women with PCOS candidate for IVF. We did not observe any significant effect of selenium supplementation on gene expression levels of lipoprotein(a) [LP(a)] in lymphocytes of women with PCOS candidate for IVF. Overall, selenium supplementation for 8 weeks in lymphocytes of women with infertile PCOS candidate for IVF significantly increased gene expression levels of PPAR-γ and GLUT-1 and significantly decreased gene expression levels of LDLR, but did not affect LP(a).

CLINICAL TRIAL REGISTRATION NUMBER

http://www.irct.ir : IRCT201704245623N113.