Effect of Different Selenium Supplementation Levels on Oxidative Stress, Cytokines, and Immunotoxicity in Chicken Thymus

Effect of Selenium and Selenoproteins on Radiation Resistance

With the advancement of radiological medicine and nuclear industry technology, radiation is increasingly used to diagnose human health disorders. However, large-scale nuclear leakage has heightened concerns about the impact on human organs and tissues. Selenium is an essential trace element that functions in the body mainly in the form of selenoproteins. Selenium and selenoproteins can protect against radiation by stimulating antioxidant actions, DNA repair functions, and immune enhancement. While studies on reducing radiation through antioxidants have been conducted for many years, the underlying mechanisms of selenium and selenoproteins as significant antioxidants in radiation damage mitigation remain incompletely understood. Therefore, this paper aims to provide new insights into developing safe and effective radiation protection agents by summarizing the anti-radiation mechanism of selenium and selenoproteins.

Hydroxy-Selenomethionine Mitigated Chronic Heat Stress-Induced Porcine Splenic Damage via Activation of Nrf2/Keap1 Signal and Suppression of NFκb and STAT Signal

Chronic heat stress (CHS) compromised the immunity and spleen immunological function of pigs, which may associate with antioxidant suppression and splenocyte apoptosis and splenic inflammation. Selenium (Se) exhibited antioxidant function and immunomodulatory through selenoprotein. Thus, this study aimed to investigate the protective effect of dietary hydroxy-selenomethionine (Selisso®, SeO) on chronic heat stress (CHS)-induced porcine splenic oxidative stress, apoptosis and inflammation. Growing pigs were raised in the thermoneutral environment (22 ± 2 °C) with the basal diet (BD), or raised in hyperthermal conditions (33 ± 2 °C) with BD supplied with 0.0, 0.2, 0.4 and 0.6 mg Se/kg SeO for 28 d, respectively. The results showed that dietary SeO supplementation recovered the spleen mass and enhanced the splenic antioxidant capacity of CHS growing pigs. Meanwhile, SeO activated the Nrf2/Keap1 signal, downregulated p38, caspase 3 and Bax, inhibited the activation of NFκb and STAT3, and enhanced the protein expression level of GPX1, GPX3, GPX4, SELENOS and SELENOF. In summary, SeO supplementation mitigates the CHS-induced splenic oxidative damages, apoptosis and inflammation in pigs, and the processes are associated with the activation of Nrf2/Keap1 signal and the suppression of NFκb, p38(MAPK) and STAT signal. It seems that the antioxidant-related selenoproteins (GPXs) and functional selenoproteins (SELENOS and SELENOF) play important roles in the alleviation processes.

Effects of Inorganic and Organic Manganese Supplementation on Growth Performance, Tibia Development, and Oxidative Stress in Broiler Chickens

Manganese (Mn) is an essential trace element for broiler chickens; its deficiency causes tibial dyschondroplasia (TD) characterized by lameness and growth retardation. Inorganic and organic manganese sources are used in global poultry production, but there is a lack of systematic investigations to compare the bioavailability among them. In this study, 120 1-day-old Arbor Acres (AA) broilers were randomly divided into four groups (n = 30), i.e., control group (Mn sulfate, 60 mg/kg), Mn-D group (Mn deficiency, 22 mg/kg), Mn-Gly group (Mn glycinate, 60 mg/kg), and Mn-Pro group (Mn proteinate, 60 mg/kg). During the 42-day experiment, growth performance, tibial bone parameters, pathological index changes, serum biochemical changes, and oxidative stress indicators were evaluated. These results not only suggested that Mn plays a crucial role in the normal development of tibia and the maintenance of redox homeostasis in broilers, but also proved that organic Mn supplementation, especially Mn proteinate, improved the tibia development and the absorption efficiency, as well as overall oxidative stress status of broilers, suggesting that it had greater bioavailability than inorganic Mn. Thus, application of organic Mn source may be an effective way to reduce economic losses and resolve animal welfare concerns due to TD in commercial poultry farming.

Nano-Selenium and Macleaya cordata Extracts Improved Immune Functions of Intrauterine Growth Retardation Piglets under Maternal Oxidation Stress

Intrauterine growth retardation (IUGR) is the main death cause of newborn piglets in large-scale farms. To investigate the effects of maternal nano-selenium (nano-Se) and Macleaya cordata extracts (MCE) on immune functions of IUGR piglets in large scale farms, a 2 × 2 factorial design was adopted in this test, and two factors were nano-Se (0, 0.50 mg/kg) and MCE (0, 500 mg/kg). A total of 32 ternary hybrid sows (Landrace × Yorkshire × Duroc, parity 2) were used in this 25-day trial from day 90 of pregnancy to delivery. The dietary treatments were as follows: (1) CON group, basic diet (0.0 mg/kg Se); (2) Nano-Se group, basic diet + 0.50 mg/kg added Se (nano-Se); (3) MCE group, basic diet + 500 mg/kg added MCE; (4) Combined group, basic diet + 0.50 mg/kg added nano-Se and 500 mg/kg added MCE. Maternal nano-Se or combination of nano-Se and MCE diets extremely increased the superoxide dismutase (SOD), catalase (CAT), superoxide dismutase (GSH-Px) contents in the serum and liver of IUGR offspring (P < 0.05), and MCE supplementation in sow diets remarkably increased the serum superoxide dismutase (SOD), catalase (CAT), and superoxide dismutase (GSH-Px) contents of IUGR piglets (P < 0.05). Adding nano-Se, MCE, or nano-Se and MCE to sow diets decreased the malondialdehyde (MDA) content in the serum and liver of IUGR piglets (P < 0.05). The supplementation of nano-Se and combined diets extremely increased the activities of immunoglobulin G (IgG) and immunoglobulin A (IgA) in the serum and liver of IUGR offspring (P < 0.05). Maternal nano-Se, MCE, and combined diets greatly decreased the levels of tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), and interleukin-1β (IL-1β) in the serum and liver of IUGR piglets (P < 0.05). Together, the application of nano-Se and/or MCE to sow diets improved antioxidant capacities and immune functions of IUGR offspring, and alleviated oxidative stress.

Dregs of Cardamine hupingshanensis as a feed additive to improve the egg quality

Natural plant herbs have many active compounds to prevent poultry diseases and improve poultry products. However, most herbs are supplied for human medicine. Thus, for economic and sustainable development purposes, the dregs of Cardamine hupingshanensis (DCH) were developed as a feed additive to improve the egg quality of laying hens in this work. Results showed that the contents of selenium in hen serum and eggs were increased under DCH feeding. Subsequently, DCH also promotes the antioxidant capacity and immunity of laying hens through the increase of superoxide dismutase (SOD), catalase (CAT), and immunoglobulin G (IgG) by ELISA detection. Finally, production performance and egg quality were further graded by monitoring the product condition and scoring the indexes of egg quality, which also displayed that DCH as a feed additive significantly improved the egg quality by enhancing yolk color, eggshell thickness, and egg shape index.

Role of thymus in health and disease

The thymus is a primary lymphoid organ, essential for the development of T-cells that will protect from invading pathogens, immune disorders, and cancer. The thymus decreases in size and cellularity with age referred to as thymus involution or atrophy. This involution causes decreased T-cell development and decreased naive T-cell emigration to the periphery, increased proportion of memory T cells, and a restricted, altered T-cell receptor (TCR) repertoire. The changes in composition and function of the circulating T cell pool as a result of thymic involution led to increased susceptibility to infectious diseases including the recent COVID and a higher risk for autoimmune disorders and cancers. Thymic involution consisting of both structural and functional loss of the thymus has a deleterious effect on T cell development, T cell selection, and tolerance. The mechanisms which act on the structural (cortex and medulla) matrix of the thymus, the gradual accumulation of genetic mutations, and altered gene expressions may lead to immunosenescence as a result of thymus involution. Understanding the molecular mechanisms behind thymic involution is critical for identifying diagnostic biomarkers and targets for treatment help to develop strategies to mitigate thymic involution-associated complications. This review is focused on the consequences of thymic involution in infections, immune disorders, and diseases, identifying potential checkpoints and potential approaches to sustain or restore the function of the thymus particularly in elderly and immune-compromised individuals.

Molybdenum Fertilization Improved Antioxidant Capacity of Grazing Nanjiang Brown Goat on Copper-Contaminated Pasture

Copper (Cu) is an essential trace element, but excessive Cu intake can induce poor performance and Cu poisoning and result in various health problems. Cu and molybdenum (Mo) antagonize each other in vivo. Therefore, Mo can reduce the absorption and utilization of Cu. The aims of this study were to investigate the impacts of Mo fertilization on antioxidant capacity of grazing Nanjiang brown goat on Cu-polluted meadow and explore the control methods of Cu pollution in natural pasture. Fertilization and grazing experiments were carried out in Liangshan Yi Nationality Prefecture of the Western Sichuan Plateau, Sichuan Province, Southwest China. Cu-polluted meadows of 12 hm² were fenced, and randomly divided into two groups (3 replications/group, 2 hm²/replication), control group and treatment group, fed with basic diets supplemented with 0 and 3 kg Mo/hm² [ammonium molybdate tetrahydrate, (NH₄)₆Mo₇O₂₄·4H₂O], respectively. In the current study, 36 healthy Nanjiang brown goats (1 year old, 32.8 ± 1.1 kg) were randomly divided into two groups (3 replications/group, 6 goats/replication) and assigned to the experimental pastures. The grazing experiment lasted for 60 days. The results showed that the concentration of Mo in soil in treatment group was 96.28 mg/kg, far exceeding the normal levels. At days 30 and 60, the levels of Hb, RBC, and PCV in blood in treatment group and the activities of serum SOD, GSH-Px, T-AOC, CAT, and Cp were higher than those in control group (P < 0.01). The MDA content in treatment group was lower than that in control group (P < 0.01). The contents of Cu in blood and liver in treatment goats were lower than those in control animals (P < 0.01). The contents of Zn and Mo in blood and liver in treatment goats were higher than those in control animals (P < 0.01). The Mn content in liver in treatment group was higher than that in control animals (P < 0.01). These results indicated that fertilization of (NH₄)₆Mo₇O₂₄ not only markedly influenced the mineral contents in blood and liver, but also extremely improved antioxidant capacity of grazing Nanjiang brown goat from fertilized pastures and relieved the damage caused by Cu pollution.

Potential Role of Selenium in the Treatment of Cancer and Viral Infections

Selenium has been extensively evaluated clinically as a chemopreventive agent with variable results depending on the type and dose of selenium used. Selenium species are now being therapeutically evaluated as modulators of drug responses rather than as directly cytotoxic agents. In addition, recent data suggest an association between selenium base-line levels in blood and survival of patients with COVID-19. The major focus of this mini review was to summarize: the pathways of selenium metabolism; the results of selenium-based chemopreventive clinical trials; the potential for using selenium metabolites as therapeutic modulators of drug responses in cancer (clear-cell renal-cell carcinoma (ccRCC) in particular); and selenium usage alone or in combination with vaccines in the treatment of patients with COVID-19. Critical therapeutic targets and the potential role of different selenium species, doses, and schedules were discussed.

The Combinations of Sulfur and Molybdenum Fertilization Improved Antioxidant Capacity in Grazing Nanjiang Brown Goat

To assess the impacts of sulfur (S) and molybdenum (Mo) fertilization on antioxidant capacity of grazing Nanjiang brown goat in copper (Cu)-polluted meadow, and explore the control methods of Cu pollution in natural pasture, fertilizer treatments and grazing experiments were carried out in Garzê Tibetan Autonomous Prefecture of the Western Sichuan Plateau, Sichuan Province, Southwest China. 24 hm² Cu-polluted meadows were fenced and randomly divided into four groups (3 replications/group, 2 hm²/replication): (1) control group, no fertilizer; (2) treatment groups, applied 1 kg Mo+40 kg S, 2 kg Mo+80 kg S, and 3 kg Mo+120 kg S per hectare for group I, group II, and group III, respectively. Seventy-two healthy Nanjiang brown goats (1 year old, 30.9 ± 1.1 kg) were randomly divided into 4 groups (3 replications/group, 6 goats/replication) and assigned to the tested pastures. The grazing experiment lasted for 60 days. The results showed that the contents of N, S, Mn, Zn, and Mo in herbage in fertilized pastures were higher than those in control group (P < 0.01). The contents of Cu and Se in herbage in fertilized pastures were lower than those in control group (P < 0.01). There were no differences among the fertilized pastures (P > 0.05). The contents of Mn, Zn, Mo, and S in serum and liver in the treatment goats were higher than those in control animals (P < 0.01). The contents of Cu and Se in serum and liver in the treatment goats were lower than those in control animals (P < 0.01). There was no difference in Fe and Co contents in herbage, serum, and liver among the four groups (P > 0.05). The levels of Hb, RBC, and PCV in blood in the treatment goats and the activities of SOD, GSH-Px, T-AOC, CAT, and Cp in serum were higher than those in control goats (P < 0.01). The contents of MDA in the treatment goats were lower than those in control animals (P < 0.01). The contents of serum Cu and Mo, and liver Cu in group III were lower than those in group I and group II (P < 0.01). Taken together, the combinations of S and Mo fertilization did not influence the mineral contents in herbage, serum, and liver, but reduced the toxicity of Cu in Cu-polluted grassland and improved antioxidant capacity in grazing Nanjiang brown goat from fertilized pastures.

Elements and COVID-19: A Comprehensive Overview of Studies on Their Blood/Urinary Levels and Supplementation with an Update on Clinical Trials

Simple Summary

COVID-19 is a disease caused by the SARS-CoV-2 coronavirus spreading mainly through person-to-person contact. It has caused millions of deaths around the world and lasting health problems in individuals who have survived the disease. This review concisely summarizes certain issues related to COVID-19 with a focus on elements and gives an update on clinical trials where some minerals will be tested/have been tested alone or in combination with drugs, vitamins, or plant extracts/herbal formulations in COVID-19 patients and in those at higher COVID-19 risk.

Abstract

The current report provides a brief overview of the clinical features, hematological/biochemical abnormalities, biomarkers, and AI-related strategies in COVID-19; presents in a nutshell the pharmacological and non-pharmacological therapeutic options; and concisely summarizes the most important aspects related to sociodemographic and behavioral factors as well as comorbidities having an impact on this disease. It also gives a brief outline of the effect of selected elements on immune response and collects data on the levels of micro-/macro-elements and toxic metals in the blood/urine of SARS-CoV-2 infected patients and on supplementation with minerals in COVID-19 subjects. Moreover, this review provides an overview of clinical trials based on the use of minerals alone or in combination with other agents that can provide effective responses toward SARS-CoV-2 infection. The knowledge compiled in this report lays the groundwork for new therapeutic treatments and further research on biomarkers that should be as informative as possible about the patient’s condition and can provide more reliable information on COVID-19 course and prognosis. The collected results point to the need for clarification of the importance of mineral supplementation in COVID-19 and the relationships of the levels of some minerals with clinical improvement.

The combinations of sulfur and molybdenum fertilizations improved antioxidant capacity of grazing Guizhou semi-fine wool sheep under copper and cadmium stress

Mineral development and metal smelting are the main sources of heavy metal pollution, and copper (Cu) and cadmium (Cd) are the most serious mineral elements in heavy metal pollution. Food chain is the main channel for Cu and Cd to enter human body. Excessive accumulation of Cu and Cd can lead to a variety of diseases and threaten human health. Therefore, it is urgent to repair Cu and Cd-contaminated soil. Previous several studies found that sulfur (S) and molybdenum (Mo) had the effect of alleviating the decrease of antioxidant capacity caused by heavy metal poisoning. To investigate the co-combinations of S and Mo fertilizations on antioxidant capacity of grazing Guizhou semi-fine wool sheep in Cu and Cd-contaminated meadow, and explore the control methods of co-pollutions of Cu and Cd in natural pastures, fertilizing and grazing experiments were carried out in the Wumeng Prairie in the northwest of Guizhou Province, Southwest China. 24 hm² Cu and Cd-polluted meadows were fenced, and were randomly divided into four groups with 3 replications per group and 2 hm² per replication. The tested groups included the control group (no fertilizer) and the three treatment groups, applied 40 kg S + 1 kg Mo, 80 kg S + 2 kg Mo, and 120 kg S + 3 kg Mo per hectare for group I, group II, and group III, respectively. 72 healthy Guizhou semi-fine wool sheep (one year old, 33.9 ± 1.2 kg) were randomly assigned to the tested pastures with 18 sheep per group. The grazing experiment lasted for 60 days. The results showed that the contents of Mn, Zn, Mo, and S in herbage in fertilized pastures were higher than that in the control group (P < 0.05). The content of Cu in herbage in fertilized pastures was lower than that in the control group (P < 0.05). The contents of Mn, Zn, Mo, and S in serum of grazing Guizhou semi-fine wool sheep were higher than that in the control group (P < 0.05). The content of Cu in serum of grazing Guizhou semi-fine wool sheep was lower than that in the control group (P < 0.05). The levels of blood Hb, RBC, and PCV, and the activities of serum SOD, GSH-Px, T-AOC, CAT, and Cp in group Ⅲ were higher than that in the control group, group Ⅰ, and group Ⅱ (P < 0.05). The MDA content of sheep in group Ⅲ was lower than that in the other treatment sheep (P < 0.05). In summary, the combinations of S and Mo fertilizers influenced the mineral contents in herbage and serum of grazing Guizhou semi-fine wool sheep. The combinations of 120 kg S + 3 kg Mo fertilizer reduced the toxicity and improved antioxidant capacity of grazing Guizhou semi-fine wool sheep in Cu and Cd-polluted grasslands.

Effects of Nano-selenium Poisoning on Immune Function in the Wumeng Semi-fine Wool Sheep

The Wumeng semi-fine wool sheep is vital to the production system in Southwest China. To study the effects of nano-selenium (Nano-Se) poisoning in the Wumeng semi-fine wool sheep, poisoning model was established. A total of 20 animals with an average initial body weight (BW) of 35.57 ± 3.31 kg were used in this study. After 1-week-long acclimatization period, all animals were randomly divided into two groups: (1) control, with no any treatment; (2) Nano-Se group, orally administered 5 mg Nano-Se (BW/kg/day). There were 10 replications/group and one sheep/replication. The experiment lasted for 30 days. Compared with the control, hemoglobin, erythrocyte count, and packed cell volume in Nano-Se group markedly decreased (P < 0.01), and the activities of serum lactate dehydrogenase, glutamic oxaloacetic transaminase, cereal third transaminase, and alkaline phosphatase in Nano-Se group significantly increased (P < 0.01). T₃ and FT₃ in serum in Nano-Se group were greatly lower than those in the control (P < 0.01). Contents of T₄, FT₄, and TSH in serum in Nano-Se group were extremely higher than those in the control (P < 0.01). Levels of IgG, IgM, IgA, interleukin 2 (IL-2), and tumor necrosis factor-alpha (TNF-α) in Nano-Se group were much lower than those of the control (P < 0.01), but levels of interleukin 6 (IL-6) and interleukin-1β (IL-1β) were greatly higher than those in the control (P < 0.01). Compared with the control, serum superoxide dismutase, glutathione peroxide, total antioxidant capacity, and catalase from Nano-Se group extremely decreased (P < 0.01), and content of serum malondialdehyde in Nano-Se group markedly increased (P < 0.01). The current results indicated that the blood parameters in the Wumeng semi-fine wool sheep were affected by Nano-Se poisoning, and the immune function and antioxidant capacity were greatly reduced too.

Mesenchymal Stromal Cell-Derived Extracellular Vesicles Restore Thymic Architecture and T Cell Function Disrupted by Neonatal Hyperoxia

Treating premature infants with high oxygen is a routine intervention in the context of neonatal intensive care. Unfortunately, the increase in survival rates is associated with various detrimental sequalae of hyperoxia exposure, most notably bronchopulmonary dysplasia (BPD), a disease of disrupted lung development. The effects of high oxygen exposure on other developing organs of the infant, as well as the possible impact such disrupted development may have on later life remain poorly understood. Using a neonatal mouse model to investigate the effects of hyperoxia on the immature immune system we observed a dramatic involution of the thymic medulla, and this lesion was associated with disrupted FoxP3⁺ regulatory T cell generation and T cell autoreactivity. Significantly, administration of mesenchymal stromal cell-derived extracellular vesicles (MEx) restored thymic medullary architecture and physiological thymocyte profiles. Using single cell transcriptomics, we further demonstrated preferential impact of MEx treatment on the thymic medullary antigen presentation axis, as evidenced by enrichment of antigen presentation and antioxidative-stress related genes in dendritic cells (DCs) and medullary epithelial cells (mTECs). Our study demonstrates that MEx treatment represents a promising restorative therapeutic approach for oxygen-induced thymic injury, thus promoting normal development of both central tolerance and adaptive immunity.

Potential benefits of selenium supplementation in patients with kidney disease

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.

Implications of Oxidative Stress and Cellular Senescence in Age-Related Thymus Involution

The human thymus is a primary lymphoepithelial organ which supports the production of self-tolerant T cells with competent and regulatory functions. Paradoxically, despite the crucial role that it exerts in T cell-mediated immunity and prevention of systemic autoimmunity, the thymus is the first organ of the body that exhibits age-associated degeneration/regression, termed “thymic involution.” A hallmark of this early phenomenon is a progressive decline of thymic mass as well as a decreased output of naïve T cells, thus resulting in impaired immune response. Importantly, thymic involution has been recently linked with cellular senescence which is a stress response induced by various stimuli. Accumulation of senescent cells in tissues has been implicated in aging and a plethora of age-related diseases. In addition, several lines of evidence indicate that oxidative stress, a well-established trigger of senescence, is also involved in thymic involution, thus highlighting a possible interplay between oxidative stress, senescence, and thymic involution.

Mechanism Underlying the Protective Effect of Selenium on NO-Induced Oxidative Damage in Bovine Mammary Epithelial Cells

This experiment was conducted to investigate the effects and mechanism of selenium (Se) on antioxidant and immune function of bovine mammary epithelial cells (BMEC) damaged by nitric oxide (NO). The third-generation BMEC was randomly divided into eight treatments with six replicates. The BMEC in the control group was cultured in the medium without Se and diethylenetriamine/NO (DETA/NO) for 30 h. For the DETA/NO group and Se protection group BMEC were exposed to different concentrations of Se (0, 10, 20, 50, 100, 150, and 200 nmol/L) for 24 h, followed by treatment with DETA/NO (1000 μmol/L) for 6 h. Compared with the control group, DETA/NO decreased proliferation rate and activity of thioredoxin reductase (TrxR; P < 0.05). Additionally, DETA/NO decreased the gene expression of both nuclear factor-E2-related factor 2 (Nrf2) and TrxR, as well as the protein expression level of TrxR. However, the activity, and expression levels of inducible nitric oxide synthase (iNOS), as well as the concentration and gene expression level of interleukin-1β (IL-1β) and the concentration of NO significantly increased (P < 0.05). The gene expression levels of indexes related to the mitogen-activated protein kinase (MAPK) signaling pathway showed similar changes. Treatment of BMEC with Se significantly reversed DETA/NO-induced changes in a linear or quadratic dose-dependent manner (P < 0.05), with greatest benefit at 50 nmol/L. These data suggests that Se improves the antioxidant function of BMEC, and protects cells from DETA/NO-induced oxidative damage, primarily by enhancing the activity of TrxR and decreasing the concentration of NO through modulation of Nrf2 and MAPK signaling pathways.

A Note on Fatty Acids Profile of Meat from Broiler Chickens Supplemented with Inorganic or Organic Selenium

This investigation evaluated, in broiler chickens Pectoralis and Gastrocnemius muscles, the effect of the dietary supplementation with sodium selenite (0.3 ppm) versus selenomethionine (0.3 ppm), on the fatty acids composition, lipids indices, and enzymes indexes for desaturase, elongase, and thioesterase. The selenium reduced, in both muscles, the content of atherogenic fatty acids, C14:0 and C16:0, while it increased the C18:1 level. On the other hand, selenium increased, in both muscles, the content of C18:3n3 and EPA, but not DPA and DHA. No selenium effect was detected for PUFA/SFA, n-6, n-3, n-6/n-3, and atherogenic and thrombogenic indices. As for the enzyme indexes, a selenium effect is only detected for thioesterase. Taken together, the results highlight the potential effect of dietary selenium, mainly selenomethionine, in the modulation of the composition of fatty acids in chicken meat, in particular, reducing the content of atherogenic fatty acids and increasing the health promoting n-3 PUFA.