This research was conducted to study the effects of organic selenium (Se) supplements at different levels on pork loin quality during storage. Fifteen pork loins were procured randomly from three groups, Con (fed basal diet), Se15 (fed 0.15 ppm organic Se along with 0.10 ppm inorganic Se), and Se45 (fed 0.45 ppm organic Se along with 0.10 ppm inorganic Se). Each sample was analyzed for Se contents, antioxidant properties (glutathione peroxidase [GPx] activity, 2,2\'-azinobis-[3-ethylbenzothiazoline-6-sulfonic acid] [ABTS] and 2,2-diphenyl-1-picrylhydrazyl [DPPH] radical scavenging activities, 2-thiobarbituric acid reactive substances), physicochemical properties (water holding capacity, pH, color), and metabolomic analysis during 14-day storage period. Se45-supplemented group showed significantly higher Se contents and GPx activity than the other groups throughout the storage period. However, other antioxidant properties were not significantly affected by Se supplementation. Selenium supplementation did not have an adverse impact on physicochemical properties. Nuclear Magnetic Resonance-based metabolomic analysis indicated that the selenium supply conditions were insufficient to induce metabolic change. These results suggest that organic Se (0.15 and 0.45 ppm) can accumulate high Se content in pork loins without compromising quality.

The transition period in high-yielding dairy cows is a critical phase marked by an elevated risk of oxidative stress. This study evaluated the effect of oral selenitetriglyceride supplementation on oxidative stress management in periparturient cows. A controlled experiment was conducted on 12 cows, divided into two groups: the experimental group (STG) received selenitetriglycerides (0.5 mg Se/kg BW), while the control group (CON) was given a placebo, starting 12 days before calving until the calving day. Blood and liver tissue samples were collected at predetermined intervals around the time of parturition. The study observed a significant increase in serum selenium levels and NEFA stabilization in the STG group compared with the control. Antioxidant parameters indicated elevated GSH-Px and CAT concentrations in the STG group. Liver gene expression analysis revealed a significant increase in SOD2 mRNA levels in the STG group (FC = 4.68, p < 0.01). Conversely, GSH-Px3 expression significantly decreased (FC = 0.10, p < 0.05) on the 7th day postpartum in the CON group. However, SOD1, SOD3, and CAT expressions remained stable in both groups. These findings highlight the beneficial role of selenitetriglycerides in enhancing antioxidant capacity and influencing specific gene expressions associated with oxidative stress management in dairy cows during the peripartum period.

Selenium (Se) is an essential trace element for maintaining human health, for example, plays a crucial role in preventing aging-related diseases. However, most studies on the health effects of Se among the community middle-aged and elderly have been observational or the health indices were single, and the related study among the Chinese population is limited. Additionally, China is recognized as among the countries facing a significant deficiency in Se, and Se contents in the human body may decrease with age. Therefore, a two-step study was conducted to explore the health effects of Se exposure and supplementation among such populations in China. Firstly, a retrospective cohort study was conducted to compare the health outcomes between such populations residing in Se-rich regions and non-Se-rich regions, involving a total of 102 subjects, with 51 residing in Se-rich regions and 51 in non-Se-rich regions. The hair-Se (H-Se) contents, serum-Se (S-Se) contents, and total cholesterol of subjects from Se-rich regions were significantly higher than their counterparts. Notably, significant positive associations were observed between S-Se and lipids. Secondly, a before-after self-control Se supplementation study among subjects residing in non-Se-rich regions was conducted. A total of 40 subjects administered Se tablets orally for 30 days, with Se of 120 μg/day. The results showed significant increases in H-Se and S-Se. Se supplementation also exhibited positive effects on alanine aminotransferase, homocysteine, and fasting glucose; however, high-density lipoprotein cholesterol significantly decreased. Overall, the community middle-aged and elderly residing in Se-rich regions or receiving quantitative Se supplementation could effectively improve Se contents in bodies and certain health indices, excluding lipids. These improvements encompass liver function, cardiovascular health, and glucose metabolism. These findings enhance our understanding of how Se impacts the health of the middle-aged and elderly, emphasizing the significance of targeted interventions for such populations in non-Se-rich regions. Trial registration: ChiCTR2000040987 ( https://www.chictr.org.cn ).

Selenium (Se) is an essential trace element for human health and plays an important role in the development and maintenance of central nervous system functions. Se deficiency has been associated with cognitive decline and increased oxidative stress. The increase in oxidative stress is one of the hypotheses for the emergence and worsening of neurodegenerative diseases, such as Alzheimer\'s disease (AD). To investigate the neuroprotective effects of organic Se compounds in human neuroblastoma cells (SH-SY5Y) differentiated into cholinergic neurons-like. The SH-SY5Y cells were differentiated into cholinergic neuron-like with retinoic acid (RA) and brain-derived neurotrophic factor (BDNF). AD was mimicked exposing the cells to okadaic acid (OA) and beta-amyloid protein (Aβ). The neuroprotective effect of organic Se compounds, selenomethionine (SeMet) and Ebselen, was evaluated through cell viability tests, acetylcholinesterase and antioxidant enzyme activities, and detection of reactive oxygen species (ROS). None of the SeMet concentrations tested protected against the toxic effect of OA + Aβ. On the other hand, previous exposure to 0.1 and 1 µM Ebselen protected cells from the toxic effect of OA + Aβ. Cell differentiation induced by RA and BDNF exposure was effective, showing characteristics of neuronal cells, and pointing to a promising model of AD. Ebselen showed a protective effect, but more studies are needed to identify the mechanism of action.

Selenium (Se) is a trace element crucial for human health. Recently, the impact of Se supplementation on gut microbiota has been pointed out as well as its influence on the expression of certain selenoproteins and gut metabolites. This study aims to elucidate the link between Se supplementation, brain selenoproteins and brain metabolome as well as the possible connection with the gut-brain axis. To this end, an in vivo study with 40 BALB/c mice was carried out. The study included conventional (n=20) and mice model with microbiota depleted by antibiotics (n=20) under a regular or Se supplemented diet. Brain selenoproteome was determined by a transcriptomic/gene expression profile, while brain metabolome and gut microbiota profiles were accomplished by untargeted metabolomics and amplicon sequencing, respectively. The total content of Se in brain was also determined. The selenoproteins genes Dio and Gpx isoenzymes, SelenoH, SelenoI, SelenoT, SelenoV, and SelenoW and 31 metabolites were significantly altered in the brain after Se supplementation in conventional mice, while 11 selenoproteins and 26 metabolites were altered in microbiota depleted mice. The main altered brain metabolites were related to glyoxylate and dicarboxylate metabolism, amino acid metabolism, and gut microbiota that have been previously related with the gut-brain axis (e.g., members of Lachnospiraceae and Ruminococcaceae families). Moreover, specific associations were determined between brain selenoproteome and metabolome, which correlated with the same bacteria, suggesting an intertwined mechanism. Our results demonstrated the effect of Se on brain metabolome through specific selenoproteins gene expression and gut microbiota.

Overexposure to Se is detrimental to glucose metabolism, mainly because of its pro-oxidant effects and the overexpression of selenoproteins. This systematic review evaluated the effects of Se supplementation on glycaemic control in healthy rodents. The methodology followed the PRISMA. We searched the databases for articles published up to May 2022. The risk of bias and the methodological quality were assessed using the SYRCLE and CAMARADES. The results are presented as meta-analytic estimates of the overall standardised mean difference (SMD) and 95 % CI. Of the 2359 records retrieved, thirteen studies were included, of which eleven used sodium selenite and two used zero-valent Se nanoparticles as supplement. Nine studies were included in the meta-analysis. Generally, the risk of bias was high, and 23·1 % of the studies were of high quality. Supplementation with sodium selenite significantly increased fasting blood glucose (SMD = 2·57 (95 % CI (1·07, 4·07)), I2 = 93·5 % (P = 0·001). Subgroup analyses showed effect size was larger for interventions lasting between 21 and 28 d (SMD = 25·74 (95 % CI (2·29, 9·18)), I2 = 96·1 % (P = 0·001)) and for a dose of 864·7 μg/kg/d of sodium selenite (SMD = 10·26 (95 % CI (2·42, 18·11), I2 = 97·1 % (P = 0·010)). However, it did not affect glutathione peroxidase activity (SMD = 0·60 (95 % CI (-0·71, 1·91)), I2 = 83·2 % (P = 0·37)). The current analysis demonstrated the adverse effects of sodium selenite supplementation on glycaemic control in healthy rodents.

This study investigated the effect of dietary selenium supplementation (organic and inorganic) of late-gestation ewes on blood selenium concentrations and metabolic and antioxidant status indicators in ewes and their lambs. In addition, the efficacy of selenium transfer from ewes to lambs during the suckling period was determined. The study was conducted on 30 Merinolandschaf ewes and their lambs and lasted four months. The feed mixture of the control group (group I) contained no added selenium, while the feed mixture of group II was enriched with 0.3 mg/kg of organic selenium sources and the third group with 0.3 mg/kg of inorganic selenium sources. In ewes and their lambs, selenium supplementation significantly (p < 0.01; p < 0.05) increased selenium concentration, glutathione peroxidase, and superoxide dismutase activity and decreased malondialdehyde concentration compared to the control group. Selenium supplementation had a positive effect on metabolism and hematological indicators in lambs. A positive correlation was found between antioxidant indicators in the whole blood of ewes and lambs. The good transfer of selenium from ewes to lambs was complemented by higher correlation coefficients when the feed mixture was supplemented with organic compared to inorganic selenium.

Introduction: The efficacy of selenium supplementation was elusive for polycystic ovary syndrome. This meta-analysis aimed to explore the efficacy of selenium supplementation for polycystic ovary syndrome. Methods: PubMed, EMbase, Web of science, EBSCO, Cochrane library database, CNKI, Chongqing VIP database and Wanfang databases have been searched through July 2022 and we included randomized controlled trials (RCTs) reporting the effect of selenium supplementation versus placebo in patients with polycystic ovary syndrome. Results: Five RCTs were included in the meta-analysis. Compared with placebo group for polycystic ovary syndrome, selenium supplementation was associated with significantly reduced total testosterone (SMD=-0.42; 95% CI=-0.78 to -0.06; p = 0.02) and cholesterol (SMD=-0.71; 95% CI=-1.41 to -0.02; p = 0.04), but revealed no remarkable influence on SHBG (SMD=-0.52; 95% CI=-1.29 to 0.25; p = 0.19), triglyceride (SMD=-1.45; 95% CI=-3.62 to 0.73; p = 0.19), LDL (SMD=-0.17; 95% CI=-0.72 to 0.37; p = 0.53), FPG (SMD=-0.95; 95% CI=-3.72 to 1.82; p = 0.50) or HOMA-IR (SMD=-0.51; 95% CI=-3.79 to 2.77; p = 0.76). Conclusions: Selenium supplementation may be able to improve the metabolic response for polycystic ovary syndrome, and this finding should be interpreted with caution.

Trace element deficiency is common among patients with end-stage renal disease (ESRD); the reason is that since these patients undergo dialysis, they lose these elements more than healthy people, and also the use of trace elements is restricted due to loss of appetite. Selenium (Se) is a trace element that is essential for the oxidative stress defense system. Se deficiency leads to some complications similar to those often seen in ESRD patients, such as all-cause mortality due to cardiovascular diseases, bone loss, uric acid elevation, and anemia. This article aims to review the evidence on consequences of Se deficiency in ESRD patients, as well as effects of Se supplementation in hemodialysis patients. Multiple databases were searched to summarize the available evidence on selenium\'s role in kidney diseases. Since the complications of ESRD and those of Se deficiency are mostly similar, this triggers the idea that Se deficiency may be considered as a cause of these problems, but it needs to be more assessed that Se deficiency is a single factor or there are other factors participated in. Also the role of Se supplementation on resolving the mentioned complications, needs to be more studied through welldesigned clinical studies.

Intake of dietary antioxidants is inversely associated with reduced markers of atherosclerosis development such as carotid intima-media thickness (CIMT).
This study was designed to assess the effects of selenium supplementation on CIMT and metabolic profiles of in diabetic hemodialysis (HD) patients.
This randomized, double-blind, placebo-controlled trial was performed on 60 diabetic HD patients. Subjects were randomly assigned to receive selenium supplements or placebo (starch). Individuals in the selenium group (n = 30) received 200 μg selenium per day in the placebo group (n = 30) received for 24 weeks. Fasting blood samples were taken at the study baseline and after 24 weeks of intervention.
Following the administration of selenium supplements, was observed a significant reduction in serum insulin levels (P = 0.003), insulin resistance (P = 0.003), total cholesterol (P = 0.008), LDL-cholesterol (P < 0.001) and C-reactive protein (CRP) (P < 0.001), and a significant increase in insulin sensitivity (P < 0.001), HDL-cholesterol (P < 0.001) and total glutathione (GSH) (P < 0.001) compared with the placebo.
Selenium supplementation in diabetic HD patients had beneficial effects on markers of insulin metabolism, total-, LDL-, HDL-cholesterol, CRP and GSH levels. This trial was registered at www.irct.ir as http://www.irct.ir: IRCT20170513033941N47.