Generational differences in selenium status of women

In this cross-sectional study of three generations of women, daughters (19–26 yr), mothers (40–58 yr) and maternal grandmothers (67–84 yr) from the same 10 families in central Ohio were studied to determine the effect of life-cycle differences, including estrogen status, on selenium status. Plasma and red blood cell (RBC) selenium and glutathione peroxidase (GPx) activities were determined and typical dietary selenium intakes were calculated from food-frequency questionnaires. Selenium status was lowest in the oldest generation. Plasma selenium of daughters and grandmothers were significantly lower than those of mothers, and plasma GPx and RBC selenium of grandmothers were also lower than those of the mothers. A positive correlation (r=0.42, p<0.04) was found between plasma estrogen and plasma selenium concentrations. Selenium intakes of all groups were adequate and no differences in selenium intakes were found among groups. The results of this study indicate that selenium status fluctuates during the female life cycle and is related to estrogen status.     

Alterations in plasma essential trace elements selenium, manganese, zinc, copper, and iron concentrations and the possible role of these elements on oxidative status in patients with childhood asthma

The aim of the present study is to evaluate the status of plasma essential trace element selenium (Se), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) concentrations and the effect of these elements on oxidative status in patients with childhood asthma. Plasma Se, Mn, Cu, and Zn concentrations were determined by atomic absorption spectrophotometry (AAS) and Fe concentrations, malondialdehyde (MDA), and total antioxidant capacity (TAC) were determined by the colorimetric method. The plasma MDA/TAC ratio was calculated as an index of oxidative status. Plasma albumin levels were measured to determine nutritional status. Plasma Fe concentrations, MDA levels and the MDA/TAC ratio were significantly higher (p<0.001, p<0.001, and p<0.01, respectively) and Se and Mn concentrations and TAC were lower (p<0.01, p<0.05, and p<0.01, respectively) in patients when compared to the healthy subjects. Plasma Zn, Cu, and albumin levels were not found to be significantly different in patients and controls (p>0.05). There were positive relationships between plasma MDA and Fe (r=0.545, p<0.001) and TAC and Se (r=0.485, p<0.021), and a negative correlation between TAC and MDA values (r= −0.337, p<0.031) in patients with childhood asthma. However, there was no correlation between these trace elements and albumin content in patient groups. These observations suggest that increased Fe and decreased Se concentrations in patients with childhood asthma may be responsible for the oxidant/antioxidant imbalance.     

Plasma micronutrient concentrations in infants undergoing therapy for phenylketonuria

Twenty-seven infants with classical phenylketonuria were evaluated longitudinally for 6 mo while ingesting Phenex^TM -1 Amino Acid Modified Medical Food With Iron as their primary protein source. Intake of selected nutrients and biochemical indices of trace and ultratrace mineral status and plasma retinol and α-tocopherol concentrations were evaluated. The means of iron status indices (complete blood count, plasma ferritin, iron, transferrin saturation, total iron binding capacity) and the plasma concentrations of trace and ultratrace minerals (copper, manganese, molybdenum, selenium, zinc) and plasma retinol and α-tocopherol were in the reference ranges. Vitamin A intakes (r = 0.49,p < 0.05) and plasma retinol-binding protein concentrations (r = 0.42,p < 0.05) were positively correlated with plasma retinol concentrations at 3 mo of study. At 6 mo, concentrations of plasma transthyretin (r = 0.72,p < 0.01) and retinolbinding protein (r = 0.48,p < 0.05) were positively correlated with plasma retinol concentrations. At 6 mo, concentrations of plasma transthyretin (r = 0.52,p < 0.05) were positively correlated with retinol-binding protein concentrations. Phenex-1 supports normal mean iron status indices and mean concentrations of trace and ultratrace minerals, retinol, and α-tocopherol when fed in adequate amounts.     

Concentrations of cadmium,lead, selenium,and zinc in human blood and seminal plasma

The concentrations of cadmium, lead, selenium, and zinc in blood and seminal plasma were determined in 76 Singapore males. Except for zinc, the concentrations were generally higher in blood than in seminal plasma (cadmium, 1.31 μg/L vs 0.61 μg/L; lead, 82.6 μg/L vs 12.4 μg/L, and selenium, 163.6 μg/L vs 71.5 μg/L). The mean concentration of zinc in seminal plasma was more than 30 times higher than in blood (202 mg/L vs 6.2 mg/L). Significant positive correlations were found between the concentrations in blood and seminal plasma for the two essential trace elements: selenium (r=0.45,p<0.001) and zinc (r=0.25,p<0.05). However, no relationships were found between the concentrations in blood and seminal plasma for two toxic metals (cadmium and lead). Significant inverse correlations were observed between Cd and Zn (r=−0.40,p<0.01), and Pb and Se (r=−0.32,p<0.05) in blood, whereas significant positive correlations were noted between Cd and Se (r=0.45,p<0.01), Cd and Zn (r=0.35,p<0.05), and Se and Zn (r=0.57,p<0.001) in seminal plasma. The physiological significance of these relationships are also discussed in this paper.     

Low selenium status in alcoholic cirrhosis is correlated with aminopyrine breath test

The relationship among impaired selenium status, lipid peroxidation, and liver function was examined in 19 hospitalized patients with severe alcoholic cirrhosis. Plasma selenium was found to be significantly lower (mean±SD: 54±13 μg/L) than in healthy controls (83±11 μg/L) and plasma malondialdehyde, assessed as thiobarbituric acid reactants, which reflects lipid peroxidation, was increased (2.0±1.2 μmol/L vs <1.2 μmol/L in controls). The mean¹⁴C aminopyrine breath test, an indicator of liver function, was lower than normal (2.7±1.9 vs 6.3±0.9% in controls) and found to be significantly correlated with plasma selenium (r=0.59,p<0.05). A prospective, randomized selenium supplementation trial was conducted in a group of 16 patients who received either daily 100 μg selenium as enriched yeast during 4 mo or a placebo. Among the 10 patients who completed the study, plasma selenium significantly increased in the supplemented group (n=4; before: 58±10 μg/L, and after 101±12 μg/L,p<0.01) contrary to the placebo group (n=6, before: 47±10 μg/L, after: 57±9 μg/L, n.s.),¹⁴C aminopyrine breath test improved in three out of four selenium-supplemented patients and in three out of six placebo patients, but the small number of patients did not allow statistical evaluation. These results demonstrate that low selenium status in alcoholic cirrhosis is correlated to liver function and could be improved by supplementation.     

Essential trace elements selenium, zinc, copper, and iron concentrations and their related acute-phase proteins in patients with vivax malaria

The aim of the present study is to evaluate the status of plasma essential trace elements selenium (Se), zinc (Zn), copper (Cu), and iron (Fe) concentrations and their related acute-phase proteins, ceruloplasmin (Cp), ferritin, transferrin (Tf), and albumin levels in patients with vivax malaria. Plasma Cu and Zn concentrations were determined by atomic absorption spectrometry (AAS). Se concentrations were determined by graphite furnace AAS. Fe, Cp, Tf, and albumin levels were determined by colorimetric methods. Plasma Se, Fe, and albumin levels were found to be significantly lower (p<0.01, p<0.001, and p<0.05, respectively) and Cu, Cp, and ferritin levels and Cu/Zn ratios were significantly higher (p<0.001, p<0.001, p<0.001, and p<0.05, respectively) in patients when compared with those of healthy subjects. Plasma, Tf, and Zn levels were not found to be significantly different (p>0.05) in patients and controls. There were positive important correlations between Cu and Cp (r=0.908, p<0.001), Zn and albumin (r=0.633, p<0.001), and negative correlations between Fe and ferritin content (r=−0.521, p<0.05) and Fe and Tf (r=−0.616, p<0.01) in the patients group. Our findings demonstrated that plasma essential trace elements Se, Cu, and Fe change, but these changes might be dependent on acute-phase proteins, which were regulated as a part of defense strategies of the organism, induced by hormonelike substances.     

Effect of selenium supplementation on thyroid hormone levels and selenoenzyme activities in growing lambs

The aim of the present study was to evaluate the effects of selenium supplementation on thyroid hormone metabolism and selenoenzyme activities in lambs. Twelve 20-d-old male lambs were assigned to one of two diets: A (0.11 ppm Se) and B (supplemented with 0.2 ppm selenium as sodium selenite). Blood samples were collected weekly for the determination of T₃, T₄, and selenium levels. The response to thyrotropin-releasing hormone (TRH) challenge was estimated at the 11th and 20th wk. Animals were slaughtered at wk 20 and tissues were collected for enzyme determination. Plasma selenium concentration was significantly higher in supplemented lambs (p<0.001). Plasma T₃ and T₄ levels remained similar in both groups. Type I deiodinase activity (ID-I) was decreased in the liver (p<0.05) and increased in the pituitary (p<0.01) of supplemented animals. No ID-I activity was detected in the thyroid. Pituitary type II deiodinase activity (ID-II) remained unchanged. The response to TRH challenge did not differ between the two groups for both challenges, but in group B, the second TRH challenge (20th wk) resulted in a significantly higher T₃ response compared to the first one (11th wk) (p<0.05). In conclusion, the lack of effects of Se supplementation on thyroid hormone metabolism demonstrates that enzyme activity is homeostatically controlled and selenium is incorporated in that order to ensure the maintenance of thyroid hormone homeostasis.     

Effect of selenium supplementation on some blood biochemical parameters in male rats

The long-term effect of selenium supplementation on blood glutathione peroxidase (GSH-Px) activity and plasma TBARS’ production (as an index of peroxidation) was evaluated in 15-mo-old male rats fed a diet supplemented with 0.25 or 0.50 ppm selenium, for 12 mo. A group of nonsupplemented age-matched rats was the control. In addition, triglycerides, phospholipids, total and free cholesterol, HDL-cholesterol, and HDL-phospholipid levels were measured in plasma. Plasma testosterone levels were also determined in order to control the aging process in these animals. The GSH-Px activity and the peroxidation level were unchanged in all the groups. However, concerning the lipid parameters, a decrease in triglycerides concentration was observed in both treated groups (p<0.05). Therefore, in these experimental conditions, despite no observed changes in parameters related to lipid peroxidation, selenium seems to be involved with triglycerides metabolism, eventually improving the triglycerides status of aged animals.     

Fish eating and variations in selenium and mercury levels in plasma and erythrocytes in free-living healthy Japanese men

The levels and its interindividual and intraindividual variations of selenium (Se) and mercury (Hg) in erythrocytes and plasma were investigated in seven healthy young men during a period of 10 wk, with emphasis on the relationship to the dietary intake of several defined food items. The intraindividual variation, estimated by coefficients of variation (CVs), was 9.9% for plasma Se (PSe), 9.5% for erythrocyte Se (ESe), 42.4% for PHg, and 11.7% for EHg on the average. Significant correlations were found for mean ESe levels in each subject and his fish-eating frequency during this study (r=0.752, p<0.01). Weekly PHg levels were also correlated with average fish-eating frequency in the corresponding week of blood collection (r=0.367, p<0.05). Fish intake within 24 h before blood collection influenced PHg levels significantly.     

Plasma selenium levels in rheumatoid arthritis

The plasma selenium (Se) levels were determined in patients with rheumatoid arthritis (RA) and healthy controls. Plasma Se levels in 60 patients were found to be significantly lower than those in 60 normal, healthy controls (p<0.001). Similar significant differences were determined in sex-matched comparisons between patients and controls (p<0.001) but there was no significant difference in plasma Se levels in sex-matched comparisons in both groups (p>0.05). Our results suggest that Se is an important factor in RA.     

Synovial fluid and plasma selenium, copper, zinc, and iron concentrations in patients with rheumatoid arthritis and osteoarthritis

In recent years, a great number of studies have investigated the possible role of trace elements in the etiology and pathogenesis of rheumatoid arthritis (RA) and osteoartritis (OA). We studied synovial fluid and plasma concentrations of selenium (Se), zinc (Zn), copper (Cu), and iron (Fe) in patients with RA and OA and compared them with sex- and age-matched healthy subjects. Plasma albumin levels were measured as an index of nutritional status. Plasma Se, Cu, and Zn concentrations were determined by atomic absorption spectrophotometry and Fe concentrations were determined by the colorimetric method. Although plasma and synovial fluid Se concentration were found to be significantly lower (p<0.05, and p<0.05, respectively), Cu concentrations were significantly higher in patients with RA than those of healthy subjects and OA (p<0.05 and p<0.05, respectively). There were no significant differences in plasma and synovial fluid Zn concentrations and albumin levels among three groups (p>0.05). On the other hand, synovial fluid Cu and Fe concentrations were significantly higher in patients with OA than those of healthy subjects (p<0.05). There was a significantly positive correlation between synovial fluid Se−Cu values and Zn−Fe values in patients with RA. Our results showed that synovial fluid and plasma trace element concentrations, excluding Zn, change in inflammatory RA, but not in OA. These alterations in trace element concentrations in inflammatory Ra might be a result on the changes of the immunoregulatory cytokines.     

Plasma zinc, copper, leptin, and body composition are associated in elite female judo athletes

This study evaluated levels of plasma zinc, copper, and leptin, body composition, and their relationship in nine elite female judo athletes under two different training conditions. Body composition and biochemical measurements (hematological indexes, plasma zinc, plasma copper, and plasma leptin) were analyzed 24 h after intense training and following a 5-d period without training (no-training). Plasma leptin and plasma zinc increased with no-training. Plasma zinc correlated negatively with percent fat mass (r=−0.62; r=0.05) and positively with plasma leptin (r=0.83; p=0.002) in the no-training condition Plasma copper did not change during the study and correlated positively with plasma leptin (r=0.66; p=0.05) and with percent fat mass (r=0.80; p=0.007) after training. Percent fat mass was associated negatively with plasma zinc (r=−0.62; p=0.05) in the no-training condition. Moreover percent fat mass was negatively associated with the Zn/Cu plasma ratio under both training conditions (r<−0.78, p<0.001). These results are consistent with the possible function of zinc as a lipid-mobilizing factor and of copper as a limiting factor in energy metabolism.     

The Analysis of Copper,Selenium, and Molybdenum Contents in Frequently Consumed Foods and an Estimation of Their Daily Intake in Korean Adults

This study aimed to analyze the amounts of copper, selenium, and molybdenum among trace minerals in foods and to evaluate their daily intakes in Korean adults. Contents of copper, selenium, and molybdenum in 366 varieties of foods commonly consumed by Koreans were analyzed using inductively coupled plasma atomic emission spectrometry and inductively coupled plasma mass spectrometry, techniques with low detection limits as well as high reproducibility and precision. Next, we evaluated the status of trace mineral intake using the 24-h recall method after conducting anthropometric measurements on 249 male and 344 female adults aged 20 or older. The average daily energy intake for males was 7,452.8 kJ, significantly higher than the 6,118.3 kJ for females (p < 0.001). The average daily copper, selenium, and molybdenum intakes by males were 1,156.7, 135.5, and 12.2 μg, respectively, compared to 1,028.5, 122.9, and 10.1 μg, respectively, by females. In males, the intake levels of copper and molybdenum were both significantly higher than in females. By continuously evaluating intake levels in this manner, it is anticipated that reference intakes of trace minerals will be established.     

Differential effects of dietary selenium (Se) and folate on methyl metabolism in liver and colon of rats

A previous study compared the effects of folate on methyl metabolism in colon and liver of rats fed a selenium-deficient die (<3 μg Se/kg) to those of rats fed a diet containing supranutritional Se (2 mg selenite/kg). The purpose of this study was to investigate the effects of folate and adequate Se (0.2 mg/kg) on methyl metabolism in colon and liver. Weanling, Fischer-344 rats (n=8/diet) were fed diets containing 0 or 0.2 mg selenium (as selenite)/kg and 0 or 2 mg folic acid/kg in a 2×2 design. After 70 d, plasma homocysteine was increased (p<0.0001) by folate deficiency; this increase was markedly, attenuated (p<0.0001) in rats fed the selenium-deficient diet compared to those fed 0.2 mg Se/kg. The activity of hepatic glycine N-methyltransferase (GNMT), an enzyme involved in the regulation of tissue S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH), was increased by folate deficiency (p<0.006) and decreased by selenium deprivation, (p<0.0003). Colon and liver SAH were highest (p<0.006) in rats fed deficient folate and adequate selenium. Although folate deficiency decreased liver SAM (p<0.001), it had no effect on colon SAM. Global DNA methylation was decreased (p<0.04) by selenium deficiency in colon but not liver; folate had no effect. Selenium, deficiency did not affect DNA methyltransferase (Dnmt) activity in liver but tended to decrease (p<0.06) the activity of the enzyme in the colon. Dietary folate did not affect liver or colon Dnmt. These results in rats fed adequate selenium are similar to previous results found in rats fed supranutritional selenium. This suggests that selenium deficiency appears to be a more important modifier of methyl metabolism than either adequate or supplemental selenium. The U.S. Department of Agriculture, Agriculture Research Service, Northern Plains Area, is an equal opportunity/affirmative action employer and all agency services are available without discrimination.     

Serum selenium versus lymphocyte subsets and markers of disease progression and inflammatory response in human immunodeficiency virus-1 infection

Serum selenium levels were determined cross-sectionally in 57 HIV-infected patients who were classified according to the Centers for Disease Control (CDC) 1993 classification system. Mean serum selenium levels were lower in CDC stage II (58.7±12.2 μg/L;p<0.01;n=18) and stage III (47.6±11.3 μg/L;p<0.01;n=19) HIV-infected patients, than in healthy subjects (80.6±9.6 μg/L;n=48) and stage I patients (73.6±16.5 μg/L;n=20). Serum selenium levels were positively correlated with CD4 count, CD4/8 ratio, hematocrit, and serum albumin (r=0.42;r=0.39;r=0.48; andr=0.45;p<0.01, respectively) and inversely with serum levels of thymidine kinase (r=−0.49;p<0.01;n=49) and β2-microglobulin (r=−0.46;p<0.001;n=49). In addition, serum selenium levels in 20 randomly selected AIDS-free individuals (CDC I:n=10; CDC II:n=10) were inversely correlated with serum concentrations of interleukin-8 (IL-8) and soluble tumor necrosis factor receptors (sTNFR) types I and II. There was no correlation with serum immuneglobulin A and total serum protein levels. The results show that the progressive deprivation of serum selenium in HIV-infection is associated with loss of CD4⁺-cells and with increased levels of markers of disease progression and inflammatory response.     

The relationship between fetal and maternal selenium concentrations in sheep and goats

In this study, biological samples (slaughterhouse material) were collected from 30 sheep and 36 goats and classified according to gestational stage into either early or late gestation. Samples consisted of allantoic fluid, amniotic fluid, fetal liver, fetal kidney, fetal thyroid gland, maternal plasma and liver to determine selenium (Se) concentrations throughout gestation. The Se concentrations in the allantoic fluid, fetal liver and kidney increased significantly (p < 0.01) during late gestation. Concurrently, the Se concentrations in amniotic fluid, maternal plasma and liver decreased significantly (p < 0.01) over time. Significant (p < 0.01) positive relationships were recorded between the age of the fetus and Se concentrations in the allantoic fluid (r = 0.57–0.75), fetal liver (r = 0.43–0.59) and kidney (r = 0.80–0.81) in both sheep and goats. A significant (p < 0.05) positive relationships were also recorded between the Se concentrations in the allantoic fluid and fetal liver (r = 0.35–0.37), the maternal plasma and liver Se concentrations (r = 0.37–0.57) between sheep and goats. A significant (p < 0.05) negative correlation was recorded between the Se concentrations in the allantoic fluid with maternal plasma of sheep (r = −0.41) as well as between the fetal liver and maternal liver Se (r = −0.22 to 0.50) and a negative correlation (r = −0.42 to 0.43) (p < 0.01) between Se concentrations in the fetal liver and amniotic fluid in both sheep and goats, respectively. Se concentration in the fetal liver was significantly (p < 0.01) higher than that of the kidney and thyroid. In the thyroid gland no morphological differences were noted. Strong fetal–maternal relationships in Se concentration were evident throughout the gestational period and dams seem to sacrifice Se levels in order to maintain that in the fetus. Se concentrations in the amniotic and allantoic fluids could be used as a possible indicator of the Se status of the fetus throughout gestation.     

Effects of excess selenomethionine on selenium status indicators in pregnant long-tailed macaques (Macaca fascicularis)

Forty pregnant long-tailed macaques were treated daily for 30 d with 0, 25, 150 or 300 μg selenium as L-selenomethionine/kg body weight. Erythrocyte and plasma selenium and glutathione peroxidase specific activities, hair and fecal selenium, and urinary selenium excretion were increased by and were linearly related to L-selenomethionine dose. Hair selenium was most sensitive to L-selenomethionine dose, with an 84-fold increase in the 300 μg selenium/(kg-d) group relative to controls (r=0.917). Daily urinary selenium excretion (80-fold,r=0.958), plasma selenium (22-fold,r=0.885), erythrocyte selenium (24-fold,r=0.920), and fecal selenium (18-fold,r=0.911) also responded strongly to L-selenomethionine. Erythrocyte and plasma glutathione peroxidase specific activities increased 154% and 69% over controls, respectively. Toxicity was associated with erythrocyte selenium >2.3 μg/mL, plasma selenium >2.8 μg/mL, and hair selenium >27 μg/g. Plasma, erythrocyte, and hair selenium concentrations may be useful for monitoring and preventing the toxicity of L-selenomethionine administered to humans in cancer chemoprevention trials.     

Effect of selenium and vitamin E supplementation on lipid abnormalities in plasma, aorta, and adipose tissue of Zucker rats

Twenty-nine obese female Zucker rats (fa / fa) were fed with a laboratory chow supplemented or not with a selenium-rich yeast (Selenion), or Selenion + vitamin E, or vitamin E alone. Twelve lean female Zucker rats (Fa / Fa) of the same littermates fed with the same diet were used as control. After 32 wk of diet, obesity induced a large increase in plasma insulin and lipid levels. A significant decrease in the plasma vitamin E/triglycerides ratio (p < 0.005) and an increase in plasma thiobarbituric reactive substances (TBARS) (p < 0.005) were also observed. Plasma selenium and vitamin E increased in all supplemented rats. The plasma insulin level was decreased by selenion supplementation and the vitamin E/triglycerides ratio was completely corrected by double supplementation with Selenion + vitamin E. TBARS were also efficiently decreased in two obese groups receiving vitamin E. In plasma, adipose tissue and aorta, obesity induced an increase in palmitic acid (C16:0), a very large increase in monounsaturated fatty acids (palmitoleic acid C16:l, stearic acid C18:l) associated with a decrease in polyunsaturated n-6 fatty acids (linoleic acid C18:2 n - 6, arachidonic C20:4 n - 6). These alterations in fatty acid distribution were only partly modulated by Se and vitamin E supplements. However, in the aorta, antioxidant treatment in obese rats significantly reduced the increase in C16:0 and C16:l (p < 0.05 andp < 0.01, respectively) and the decrease in arachidonic acid (p < 0.05). These changes could be beneficial in the reduction of insulin resistance and help to protect the vascular endothelium.     

Effect of selenium supplementation on polyunsaturated fatty acids in rats

The purpose of this work was to study plasma, adipose tissue, and liver fatty acids percentages of Wistar rats that drank water supplemented with several levels of sodium selenite for 1, 3, and 6 mo. In a general way, percentages of saturated, monounsaturated, and polyunsaturated fatty acids of supplemented groups were not different from those obtained with nontreated animals in the analyzed tissues. However, in rats supplemented with 0.5 ppm Se, mainly in adipose tissue, a polyunsaturated fatty acids increase (p<0.005) was observed for all times of treatment. This could suggest that 0.5 ppm Se supplement probably exercises a protective role on polyunsaturated fatty acids in that tissue. Supplements of 6.0, 15.0, and 54.0 ppm Se did not change unsaturation levels of fatty acids in the analyzed tissues.     

Relationship among serum selenium levels,lipid peroxidation,and acute bronchiolitis in infancy

Thirty-four infants with acute bronchiolitis and 25 age-matched healthy controls were enrolled to investigate the possible relationship between serum malondialdehyde (MDA) and selenium (Se) levels and the occurrence and severity of acute bronchiolitis in children. Serum samples were taken for serum Se and MDA measurements, and the clinical score was assessed at admission. Blood was taken again from the children with bronchiolitis at 2 mo after discharge from the hospital. Mean serum MDA levels were significantly higher in patients with acute bronchiolitis than at the postbronchiolitis stage and the controls (4.2±2.5nmol./L, 1.4±0.8 nmol/L, and 0.7±0.2 nmol/L, respectively [p<0.001]). Infants with bronchiolitis had lower mean serum Se levels at the acute stage than after 2 mo (31.7±28.9μg/L versus 68.4±26.4 μg/L, p<0.05, respectively); both of which were significantly lower than the control group measurements (145.0±21.9 μg/L) (p<0.001). There was a negative correlation between serum MDA and Se levels in the patient group (=−0.85, p<0.001). The age of the patient, child's immunization status, parental smoking habit, and family crowding index were not correlated with serum Se, MDA levels, or clinical score at admission. In conclusion, increased MDA levels and impaired Se status demonstrate the presence of possible relationship of these parameters with pathogenesis of acute bronchiolitis, and antioxidant supplementation with Se might be thought to supply a beneficial effect against bronchiolitis.