Prooxidant-antioxidant balance in pregnancy: a randomized double-blind placebo-controlled trial of selenium supplementation

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.

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.

On maternal Post-Partum/Natal depression. A global underrecognized problem and the need for better Treatment strategies

BACKGROUND

Maternal Postpartum (PPD) or Postnatal Depression (PND) is believed to be the commonest medical complication postpartum. Evidence suggests a significantly higher prevalence of the disease compared to the often reported 10-15%.

METHOD

Studies were identified by accessing several databases including PubMed/Medline, PubMed Central, EBSCO, and PsycINFO.

RESULTS

Vitamin D (VD) deficiency, hormonal levels alteration (estrogen, progesterone, testosterone, oxytocin, and prolactin), thyroid dysfunction, and increased oxidative stress, play a critical role in PPD etiopathogenesis and pathophysiology.

CONCLUSIONS

Treatment strategies should include an integrated approach of antidepressants and psychotherapy, melatonin, diet, sleep improvement, exercise, VD and antioxidants supplementation, and economic and social support.

The Effects of Selenium Supplementation on Gene Expression Related to Insulin and Lipid Metabolism, and Pregnancy Outcomes in Patients with Gestational Diabetes Mellitus: a Randomized, Double-Blind, Placebo-Controlled Trial

This study was performed to evaluate the effects of selenium supplementation on gene expression related to insulin and lipid metabolism, and pregnancy outcomes in patients with gestational diabetes mellitus (GDM). The current randomized, double-blind, placebo-controlled clinical trial was conducted in 36 patients with GDM. Participants were randomly divided into two groups to intake either 200 μg/day selenium supplements as selenium yeast or placebo (n = 18 each group) for 6 weeks. Selenium supplementation upregulated peroxisome proliferator-activated receptor gamma (P = 0.03) and glucose transporter 1 (GLUT-1) (P = 0.01) in lymphocytes of subjects with GDM compared with the placebo. Selenium supplementation did not affect gene expression of low-density lipoprotein receptor (LDLR) and lipoprotein(a) [Lp(a)]. Supplementation with selenium had a significant decrease in incidence of newborns' hyperbilirubinemia (5.6% vs. 33.3%, P = 0.03) and newborns' hospitalization (5.6% vs. 33.3%, P = 0.03) compared with the placebo. Overall, we found that selenium supplementation for 6 weeks among patients with GDM significantly increased PPAR-γ and GLUT-1 expression, but did not affect gene expression of LDLR and LP(a). It also reduced incidence of newborns' hyperbilirubinemia and newborns' hospitalization. Clinical trial registration number: http://www.irct.ir: IRCT20170513033941N35.

Vitamins A and E during Pregnancy and Allergy Symptoms in an Early Childhood-Lack of Association with Tobacco Smoke Exposure

Epidemiological studies have suggested an association between maternal antioxidant levels during pregnancy and development of allergic diseases in their offspring. The aim of the study was to determine plasma vitamins A and E concentration in the 1st trimester of pregnancy, at delivery and in cord blood and to search for a relationship with allergy in up to 2-year-old children who were prenatally exposed or not exposed to tobacco smoke. The study participants included 252 mother-child pairs from Polish Mother and Child Cohort. Vitamin concentrations were measured using the HPLC-UV method, smoking status&mdash;as saliva cotinine level using the HPLC-MS/MS technique. Children&rsquo;s health status was assessed using a questionnaire and pediatricians/allergists examination. Cord plasma vitamin concentrations were significantly lower than their levels in maternal plasma in the 1sttrimester and at delivery (p < 0.001). Significantly higher concentrations of vitamin E have been shown to occur during the 1st trimester of pregnancy in plasma of the women who have actively/passively smoked cigarettes compared to the non-smokers (p < 0.02). Multivariate analysis with inclusion of a variety of confounding factors have not indicated any statistically significant associations between &beta;-carotene, vitamins A and E and the risk of food allergy, atopic dermatitis and wheezing in their children up to 2 years of age. The interaction between smoking during pregnancy and vitamins levels on the risk of allergy was not statistically significant (p < 0.4). The relationship between plasma concentration of vitamins A and E, and the risk of allergy in their young children has not been demonstrated.

Selenium: implications for outcomes in extremely preterm infants

Extremely preterm infants are at high risk for morbidities including bronchopulmonary dysplasia, intraventricular hemorrhage, and retinopathy of prematurity likely related to their exposure to reactive oxygen and nitrogen species early in life. Selenium is a trace mineral contributes to the proper function of multiple systems including immunity, redox regulation, and inflammation via the "selenoenzymes" glutathione peroxidase, thioredoxin reductase, and selenoprotein P. Given that selenium accretion via the placenta occurs primarily during the third trimester, preterm neonates are born selenium deficient. While the role of selenium in animals and adults is better described, publications are lacking in the neonatal population regarding consequences of selenium deficiency or toxicity, accurate monitoring of levels, and proper enteral and parental dosages. This review highlights the role of selenium as it relates to the optimal function of antioxidant systems in extremely preterm infants in order to highlight the gaps in knowledge as it relates to the pathogenesis and prevention of morbidities in this population.

Barberry administration and pro-oxidant-antioxidant balance in patients with metabolic syndrome

Background:

Metabolic syndrome is the constellation of several cardiometabolic risk factors, and is associated with a heightened risk of coronary heart disease (CHD). The pro-oxidant–antioxidant balance (PAB) is a measure of factors that promote and control oxidative stress. PAB may also be associated with the risk factors of CHD.

Objectives:

This study aimed to explore the impact of supplementation with barberry, a fruit rich in antioxidants, on PAB in patients with metabolic syndrome.

Patients and Methods:

A total of 106 patients diagnosed with metabolic syndrome were randomized in two groups: case and control. The case group received three capsules of barberry and the control group received three capsules of placebo for 6 weeks. Serum PAB was measured in all patients before and after the intervention.

Results:

There was no significant difference between the groups regarding their baseline PAB values (P = 0.32). A significant decrease in PAB was observed in the barberry group (P = 0.022), whilst there was no significant change in the control group (P = 0.18). The magnitude of change in PAB during the study was significantly greater in the case group compared to the control group (P = 0.01).

Conclusions:

Barberry supplementation reduces oxidative burden in patients with metabolic syndrome.

The placental pursuit for an adequate oxidant balance between the mother and the fetus

The placenta is the exchange organ that regulates metabolic processes between the mother and her developing fetus. The adequate function of this organ is clearly vital for a physiologic gestational process and a healthy baby as final outcome. The umbilico-placental vasculature has the capacity to respond to variations in the materno-fetal milieu. Depending on the intensity and the extensity of the insult, these responses may be immediate-, mediate-, and long-lasting, deriving in potential morphostructural and functional changes later in life. These adjustments usually compensate the initial insults, but occasionally may switch to long-lasting remodeling and dysfunctional processes, arising maladaptation. One of the most challenging conditions in modern perinatology is hypoxia and oxidative stress during development, both disorders occurring in high-altitude and in low-altitude placental insufficiency. Hypoxia and oxidative stress may induce endothelial dysfunction and thus, reduction in the perfusion of the placenta and restriction in the fetal growth and development. This Review will focus on placental responses to hypoxic conditions, usually related with high-altitude and placental insufficiency, deriving in oxidative stress and vascular disorders, altering fetal and maternal health. Although day-to-day clinical practice, basic and clinical research are clearly providing evidence of the severe impact of oxygen deficiency and oxidative stress establishment during pregnancy, further research on umbilical and placental vascular function under these conditions is badly needed to clarify the myriad of questions still unsettled.

A Phytochemical-rich Multivitamin-multimineral Supplement Is Bioavailable and Reduces Serum Oxidized Low-density Lipoprotein, Myeloperoxidase, and Plasminogen Activator Inhibitor-1 in a Four-week Pilot trial of Healthy Individuals

BACKGROUND

A multivitamin-multimineral supplement combined with a diverse blend of bioactive phytochemicals may provide additional antioxidant capacity and anti-inflammatory property for overall health. This convenient feature may be useful for individuals who want to increase their intake of phytochemicals.

METHODS

We conducted a pilot study in 15 healthy individuals (8 women and 7 men, mean age 41.7±14.9 years, mean body mass index 28.0±5.6) to investigate the effects of this novel formulation on biomarkers associated with oxidative stress and inflammation. After a 2-week diet that limited intake of fruits and vegetables to 2 servings/day, participants continued with the same restricted diet but began consuming 2 tablets of the study product for the subsequent 4 weeks. Fasting blood samples collected at Week 2 and Week 6 were analyzed and compared using paired t-tests for levels of carotenoids, folate, vitamin B12, homocysteine, oxidized low-density lipoprotein cholesterol (oxLDL), high-sensitivity C-reactive protein (hs-CRP), F2-isoprostane, plasminogen activator inhibitor-1 (PAI-1), and myeloperoxidase. Noninvasive peripheral arterial tonometry (EndoPAT) was also measured.

RESULTS

After 4 weeks of supplementation, plasma levels of carotenoids, folate, and vitamin B12, but not homocysteine, were significantly increased (P<.05). Serum levels of oxLDL, PAI-1 and myeloperoxidase were significantly reduced (P<.05), but F2-isoprostane, hs-CRP, and EndoPAT measures were unchanged compared with baseline. The study product was well tolerated.

CONCLUSIONS

This nutritional supplement is bioavailable as indicated by the significant increase in plasma carotenoids, vitamin B12, and folate levels and may provide health benefits by significantly reducing serum levels of oxLDL, myeloperoxidase, and PAI-1 in healthy individuals.

Prooxidant-antioxidant balance in perinatal asphyxia

OBJECTIVE

To determine the prooxidant-antioxidant balance (PAB) in neonatal asphyxia and compare it with values for PAB in healthy neonates.

METHODS

In a prospective observational study, serum PAB of umbilical cord blood of 30 neonates with asphyxia [pH < 7.2, low Apgar score, signs of respiratory distress syndrome (RDS)] as the case group and 35 healthy neonates (without an abnormal clinical event at birth and after the first week) as the control group were compared.

RESULTS

Among the 35 neonates in the control group, the average level of serum PAB was 20.00 HK units, which was significantly lower than for the 30 neonates within the case group (40.46 HK units; p = 0.019). The blood pH in the case group was significantly lower than for control group (P < 0.001). In controls, HCO3 (-) and pCO2 were 18.6 mmol/L and 38.5 mmHg respectively, whilst in the case group these values were 15.5 mmol/L and 45.7 mmHg respectively (p < 0.05).

CONCLUSIONS

Determination of PAB may be useful in the early diagnosis of perinatal asphyxia and is consistent with HCO3 (-), pCO2 and Apgar score.

Effects of selenium and light wavelengths on liquid culture of Cordyceps militaris Link

To investigate the effects of selenium and light wavelengths on the growth of liquid-cultured Cordyceps militaris and the main active components' accumulation, culture conditions as selenium selenite concentrations and light of different wavelengths were studied. The results are: adenosine accumulation proved to be significantly selenium dependent (R(2) = 0.9403) and cordycepin contents were determined to be not significantly selenium dependent (R(2) = 0.3845) but significantly enhanced by selenium except for 20 ppm; there were significant differences in cordycepin contents, adenosine contents, and mycelium growth caused by light wavelengths: cordycepin, blue light > pink light > daylight, darkness, red light; adenosine, red light > pink light, darkness, daylight, blue light; and mycelium growth, red light > pink light, darkness, daylight > blue light. In conclusion, light wavelength had a significant influence on production of mycelia, adenosine, and cordycepin, so lightening wavelength should be changed according to target products in the liquid culture of C. militaris.

Selenium enrichment on Cordyceps militaris link and analysis on its main active components

To investigate the effects of selenium on the main active components of Cordyceps militaris fruit bodies, selenium-enriched cultivation of C. militaris and the main active components of the fruit bodies were studied. Superoxide dismutase (SOD) activity and contents of cordycepin, cordycepic acid, and organic selenium of fruit bodies were sodium selenite concentration dependent; contents of adenosine and cordycep polysaccharides were significantly enhanced by adding sodium selenite in the substrates, but not proportional to sodium selenite concentrations. In the cultivation of wheat substrate added with 18.0 ppm sodium selenite, SOD activity and contents of cordycepin, cordycepic acid, adenosine, cordycep polysaccharides, and total amino acids were enhanced by 121/145%, 124/74%, 325/520%, 130/284%, 121/145%, and 157/554%, respectively, compared to NS (non-selenium-cultivated) fruit bodies and wild Cordyceps sinensis; organic selenium contents of fruit bodies reached 6.49 mg/100 g. So selenium-enriched cultivation may be a potential way to produce more valuable medicinal food as a substitute for wild C. sinensis.

The effect of selenium administration on restless leg syndrome treatment

BACKGROUND

Restless leg syndrome (RLS) is defined as an uncomfortable feeling in the limbs which is prominently sensed in legs. Dopamine system involvement is considered as the base of RLS's etiology. Because of safety, anti-oxidant and dopaminergic promoting action of selenium, this study aims to investigate the effect of selenium on restless leg syndrome treatment.

METHODS

Sixty patients with primary RLS were enrolled in this clinical trial (Irct2011103015943n1). It was based on 3 periods of drug prescription with one month wash out period. As placebo, 50 and 200 μg of selenium were administered in each separated month. The diagnosis was based on criteria published by IRLSG (International RLS Study Group). The questionnaire included 10 questions while each question's rating was between 0 and 4. Points between 1 and 10 were considered mild, 11 to 20 as moderate, 21 to 30 as severe and 31 to 40 as very severe. After end of each month of drug consumption, questionnaires were completed and each subject was asked to report the severity of disease and side effects of the drugs. At least 10 declines in scale were considered as appropriate responses.

RESULTS

Improvement (decline IRLS score >10) was significantly higher in selenium (50 and 200 μg) than placebo group.

CONCLUSION

Selenium prescription in daily recommended dose of 50 μg instead of a dopamine agonist would be an alternative treatment in improvement of RLS symptoms.