The Role and Mechanisms of Selenium Supplementation on Fatty Liver-Associated Disorder

Selenium Injection in Dam Rabbits During Gestation Has Important Effects on Progeny Productive Performance

Micromineral elements have a fundamental participation in the processes of organogenesis and fetal development. The objective of this study was to assess the effect of selenium (Se) injection in pregnant female rabbits, during organogenesis or rapid fetal growth, on the productive performance of their progeny. An experiment was carried out with 30 New Zealand female rabbits, with an average age of 6 months. At the end of mating (day 0), using a randomized complete design, the female rabbits were distributed into three experimental groups, which were assigned to the following treatments: Control, female rabbits were injected intramuscularly (IM) with 0.5 ml of saline on days 13 and 23 of gestation; Early administration, female rabbits that were injected IM with Se (0.10 mg/kg BW) on day 13 of gestation (organogenesis) and 0.5 ml of saline on day 23 of gestation; and Late administration, female rabbits that were injected IM with 0.5 ml of saline on day 13 of gestation and Se (0.10 mg/kg BW) on day 23 of gestation (rapid fetal growth). No differences were found on kindling performance of dams and pre-weaning growth of rabbit offspring. However, an injection of Se to pregnant rabbits affected the growth and development of their progeny, with the treatment leading to changes in the yield of some carcass traits (forelimb weight and forelimb muscle weight) and weights of some organs (liver, lungs, and spleen). The Se treatment (both early and late) also resulted in lower concentrations of glucose, triglycerides, and cholesterol when compared to the control group. These effects were different when Se injection was performed during organogenesis or rapid fetal development. The results from this study suggest that there are beneficial effects of gestational Se injection of rabbit dams on important productive traits of their progeny.

Association between serum trace element, mineral, and amino acid levels with non-alcoholic fatty liver disease (NAFLD) in adult women

The objective of the present study is assessment of serum trace element and amino acid levels in non-alcoholic fatty liver disease (NAFLD) patients with subsequent evaluation of its independent associations with markers of liver injury and metabolic risk.

MATERIALS AND METHODS

140 women aged 20-90 years old with diagnosed NAFLD and 140 healthy women with a respective age range were enrolled in the current study. Analysis of serum and hair levels of trace elements and minerals was performed with inductively-coupled plasma mass-spectrometry (ICP-MS). Serum amino acid concentrations were evaluated by high-pressure liquid chromatography (HPLC) with UV-detection. In addition, routine biochemical parameters including liver damage markers, alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT), were assessed spectrophotometrically.

RESULTS

The findings demonstrated that patients with NAFLD were characterized by higher ALT, GGT, lactate dehydrogenase (LDH) and cholinesterase (CE) activity, as well as increased levels of total cholesterol, low-density lipoprotein cholesterol, triglycerides, and uric acid. NAFLD patients were characterized by reduced serum and hair Co, Se, and Zn levels, as well as hair Cu content and serum Mn concentrations in comparison to controls. Circulating Ala, Cit, Glu, Gly, Ile, Leu, Phe, and Tyr levels in NAFLD patients exceeded those in the control group. Multiple linear regression demonstrated that serum and hair trace element levels were significantly associated with circulating amino acid levels after adjustment for age, BMI, and metabolic parameters including liver damage markers.

CONCLUSION

It is proposed that altered trace element handling may contribute to NAFLD pathogenesis through modulation of amino acid metabolism.

Supplementation of Micro- and Macronutrients-A Role of Nutritional Status in Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a condition in which the pathological cumulation of fat with coexisting inflammation and damage of hepatic cells leads to progressive dysfunctions of the liver. Except for the commonly well-known major causes of NAFLD such as obesity, dyslipidemia, insulin resistance, or diabetes, an unbalanced diet and imbalanced nutritional status should also be taken into consideration. In this narrative review, we summarized the current knowledge regarding the micro- and macronutrient status of patients suffering from NAFLD considering various diets and supplementation of chosen supplements. We aimed to summarize the knowledge indicating which nutritional impairments may be associated with the onset and progression of NAFLD at the same time evaluating the potential therapy targets that could facilitate the healing process. Except for the above-mentioned objectives, one of the most important aspects of this review was to highlight the possible strategies for taking care of NAFLD patients taking into account the challenges and opportunities associated with the micronutrient status of the patients. The current research indicates that a supplementation of chosen vitamins (e.g., vitamin A, B complex, C, or D) as well as chosen elements such as zinc may alleviate the symptoms of NAFLD. However, there is still a lack of sufficient data regarding healthy ranges of dosages; thus, further research is of high importance in this matter.

Examining the Pathogenesis of MAFLD and the Medicinal Properties of Natural Products from a Metabolic Perspective

Metabolic-associated fatty liver disease (MAFLD), characterized primarily by hepatic steatosis, has become the most prevalent liver disease worldwide, affecting approximately two-fifths of the global population. The pathogenesis of MAFLD is extremely complex, and to date, there are no approved therapeutic drugs for clinical use. Considerable evidence indicates that various metabolic disorders play a pivotal role in the progression of MAFLD, including lipids, carbohydrates, amino acids, and micronutrients. In recent years, the medicinal properties of natural products have attracted widespread attention, and numerous studies have reported their efficacy in ameliorating metabolic disorders and subsequently alleviating MAFLD. This review aims to summarize the metabolic-associated pathological mechanisms of MAFLD, as well as the natural products that regulate metabolic pathways to alleviate MAFLD.

Association between blood heavy metal exposure levels and risk of metabolic dysfunction associated fatty liver disease in adults: 2015-2020 NHANES large cross-sectional study

Background

The relationships between heavy metals and fatty liver, especially the threshold values, have not been fully elucidated. The objective of this research was to further investigate the correlation between blood heavy metal exposures and the risk of Metabolic dysfunction Associated Fatty Liver Disease (MAFLD) in adults.

Methods

Laboratory data on blood metal exposure levels were obtained from National Health and Nutrition Examination Survey (NHANES) data for the period 2015 to 2020 for a cross-sectional study in adults. Associations between blood levels of common heavy metals and the risk of MAFLD in adults were analyzed using multifactorial logistic regression and ranked for heavy metal importance using a random forest model. Finally, thresholds for important heavy metals were calculated using piecewise linear regression model.

Results

In a multifactorial logistic regression model, we found that elevated levels of selenium (Se) and manganese (Mn) blood exposure were strongly associated with the risk of MAFLD in adults. The random forest model importance ranking also found that Se and Mn blood exposure levels were in the top two positions of importance for the risk of disease in adults. The restricted cubic spline suggested a non-linear relationship between Se and Mn blood exposure and adult risk of disease. The OR (95% CI) for MAFLD prevalence was 3.936 (2.631-5.887) for every 1 unit increase in Log Mn until serum Mn levels rose to the turning point (Log Mn = 1.10, Mn = 12.61 μg/L). This correlation was not significant (p > 0.05) after serum Mn levels rose to the turning point. A similar phenomenon was observed for serum Se levels, with a turning point of (Log Se = 2.30, Se = 199.55 μg/L).

Conclusion

Blood heavy metals, especially Se and Mn, are significantly associated with MAFLD in adults. They have a non-linear relationship with a clear threshold.

Bioactivity of selenium-containing pyridinium salts: Prospecting future pharmaceutical constituents to treat liver diseases involving oxidative stress

Redox imbalance leads to oxidative stress that causes irreversible cellular damage. The incorporation of the antioxidant element selenium (Se) in the structure of pyridinium salts has been used as a strategy in chemical synthesis and can be useful in drug development. We investigated the antioxidant activity of Se-containing pyridinium salts (named Compounds 3A, 3B, and 3C) through in vitro tests. We focused our study on liver protein carbonylation, liver lipoperoxidation, free radical scavenging activity (1,1-diphenyl-2-picryl-hydrazil [DPPH]; 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid [ABTS]), and enzyme-mimetic activity assays (glutathione S-transferase [GST]-like; superoxide dismutase [SOD]-like). In addition, 2-(4-chlorophenyl)-2-oxoethyl)-2-((phenylselanyl)methyl)pyridin-1-ium bromide (3C) was selected to evaluate the acute oral toxicity in mice due to the best antioxidant profile. The three compounds were effective in reducing the levels of protein carbonylation and lipoperoxidation in the liver in a µM concentration range. All compounds demonstrated scavenger activity of DPPH and ABTS radicals, and GST-like action. No significant effects were detected in the SOD-like assay. Experimental data also showed that the acute oral treatment of mice with Compound 3C (50 and 300 mg/kg) did not cause mortality or change markers of liver and kidney functions. In summary, our findings reveal the antioxidant potential of Se-containing pyridinium salts in liver tissue, which could be related to their radical scavenging ability and mimetic action on the GST enzyme. They also demonstrate a low toxicity potential for Compound 3C. Together, the promising results open space for future studies on the therapeutic application of these molecules.

Alleviating effect of selenium-enriched Lactobacillus plantarum 6076 on dextran sulfate sodium-induced colitis and liver inflammation in mice

The aim of this study is to investigate the alleviating effect of selenium-enriched Lactobacillus plantarum (SL) 6076 on colitis and liver inflammation induced by sodium dextran sulfate (DSS) in mice and its potential molecular mechanisms. Lactobacillus plantarum (LA) was cultured for 3 generations on MRS medium containing sodium selenite to generate SL. LA (3.2 × 1011 CFU mL-1), low selenium Lactobacillus plantarum (LS) (3.9 × 1010 CFU mL-1, 0.35 mg mL-1 Se) and high selenium Lactobacillus plantarum (HS) (2.8 × 1010 CFU mL-1, 0.52 mg mL-1 Se) were continuously fed to mice for 21 d to observe their effects on DSS-induced colitis and liver inflammation in mice. The composition of gut microbiota was detected through high-throughput 16S rRNA sequencing, and inflammatory cytokines, oxidative stress parameters, and serum biochemical indicators were measured in the colon and liver using quantitative polymerase chain reaction (qPCR) and biochemical analysis methods. The results showed that SL alleviated inflammation symptoms in the colon and liver, reduced the expression of inflammatory factors in the colon and liver, regulated oxidative stress responses in the colon, downregulated NF-κB-P65 pathway factors, and altered the composition and structure of the gut microbiota. In summary, DSS-induced colitis may cause liver inflammation, and SL had a significant relieving effect on both colon and liver inflammation. The intervention effect of SL was better than that of LA, while HS was better than LS. SL had a significant alleviating effect on DSS-induced colitis, and may exert its therapeutic effect by downregulating NF-κB-P65 signaling pathways and regulating the structure of intestinal microbiota. This study provides a new approach for the treatment of colitis.

Effect of Organic Selenium on the Homeostasis of Trace Elements, Lipid Peroxidation, and mRNA Expression of Antioxidant Proteins in Mouse Organs

(1) In this study we determined the effect of long-term selenomethionine administration on the oxidative stress level and changes in antioxidant protein/enzyme activity; mRNA expression; and the levels of iron, zinc, and copper. (2) Experiments were performed on 4-6-week-old BALB/c mice, which were given selenomethionine (0.4 mg Se/kg b.w.) solution for 8 weeks. The element concentration was determined via inductively coupled plasma mass spectrometry. mRNA expression of SelenoP, Cat, and Sod1 was quantified using real-time quantitative reverse transcription. Malondialdehyde content and catalase activity were determined spectrophotometrically. (3) After long-term SeMet administration, the amount of Se increased by 12-fold in mouse blood, 15-fold in the liver, and 42-fold in the brain, as compared to that in the control. Exposure to SeMet decreased amounts of Fe and Cu in blood, but increased Fe and Zn levels in the liver and increased the levels of all examined elements in the brain. Se increased malondialdehyde content in the blood and brain but decreased it in liver. SeMet administration increased the mRNA expression of selenoprotein P, dismutase, and catalase, but decreased catalase activity in brain and liver. (4) Eight-week-long selenomethionine consumption elevated Se levels in the blood, liver, and especially in the brain and disturbed the homeostasis of Fe, Zn, and Cu. Moreover, Se induced lipid peroxidation in the blood and brain, but not in the liver. In response to SeMet exposure, significant up-regulation of the mRNA expression of catalase, superoxide dismutase 1, and selenoprotein P in the brain, and especially in the liver, was determined.

The effect of curcumin on anthropometric indices, blood pressure, lipid profiles, fasting blood glucose, liver enzymes, fibrosis, and steatosis in non-alcoholic fatty livers

Background

Non-alcoholic fatty liver disease (NAFLD) is the most common form of liver disease. Curcumin is a natural polyphenol that may be effective against liver steatosis and steatohepatitis. The present study aimed to evaluate the effects of phytosomal curcumin on lipid profile, fasting blood sugar, anthropometric indices, liver enzymes, fibrosis, and steatosis in non-alcoholic fatty liver patients.

Methods

The participants were randomized to the curcumin-phosphatidylserine phytosomal receiving group and the placebo receiving group and were followed up for 12 weeks. Data on anthropometric indices, lipid profile, blood glucose, blood pressure, liver enzymes, hepatic steatosis, and fibrosis were collected at the beginning and the end of the clinical trial.

Results

Supplementation for 12 weeks with phytosomal curcumin significantly reduced fibrosis and steatosis in the phytosomal curcumin receiving group compared with the placebo group (p < 0.05). Phytosomal curcumin also significantly reduced waist circumference and blood pressure compared with the placebo group (p < 0.05). There was no significant difference between the phytosomal curcumin and the placebo groups regarding changes in weight, body mass index, fasting blood glucose, liver enzymes, and lipid profile.

Conclusion

Curcumin, at a dose of 250 mg per day, might be effective in treating patients with NAFLD. Further studies are necessary to confirm these findings and to discover the underlying mechanisms.

Clinical trial registration

https://www.irct.ir/trial/43730, identifier: IRCT20121216011763N39.

Effect of Selenium Deficiency on the Development of Overt Hepatic Encephalopathy in Patients with Chronic Liver Disease

Selenium is an essential trace element to maintain good health. This retrospective study investigated the prevalence of selenium deficiency and its effect on overt hepatic encephalopathy (OHE) in patients with chronic liver disease (CLD). Patients who underwent serum selenium level measurement between January 2021 and April 2022 were enrolled. The factors associated with selenium deficiency (≤10 µg/dL) and the association between selenium deficiency and OHE were analyzed. Among 98 eligible patients, 24% were observed to have selenium deficiency, with a median serum selenium level of 11.8 µg/dL. The serum selenium levels were significantly lower in patients with cirrhosis than in those with chronic hepatitis (10.9 µg/dL vs. 12.4 µg/dL; p = 0.03). The serum selenium levels were negatively correlated with mac-2 binding protein glycan isomer, the FIB-4 index, albumin-bilirubin (ALBI) score, and Child-Pugh score. The ALBI score remained significantly associated with selenium deficiency (odds ratio, 3.23; 95% confidence interval [CI], 1.56-6.67). During a median follow-up period of 2.9 months, nine patients experienced OHE. Selenium deficiency was associated with OHE (hazard ratio, 12.75; 95% CI, 2.54-70.22). Selenium deficiency is highly prevalent in patients with CLD and is associated with an increased risk of OHE development.

Biological Activity of Selenium and Its Impact on Human Health

Selenium (Se) is a naturally occurring metalloid element essential to human and animal health in trace amounts but it is harmful in excess. Se plays a substantial role in the functioning of the human organism. It is incorporated into selenoproteins, thus supporting antioxidant defense systems. Selenoproteins participate in the metabolism of thyroid hormones, control reproductive functions and exert neuroprotective effects. Among the elements, Se has one of the narrowest ranges between dietary deficiency and toxic levels. Its level of toxicity may depend on chemical form, as inorganic and organic species have distinct biological properties. Over the last decades, optimization of population Se intake for the prevention of diseases related to Se deficiency or excess has been recognized as a pressing issue in modern healthcare worldwide. Low selenium status has been associated with an increased risk of mortality, poor immune function, cognitive decline, and thyroid dysfunction. On the other hand, Se concentrations slightly above its nutritional levels have been shown to have adverse effects on a broad spectrum of neurological functions and to increase the risk of type-2 diabetes. Comprehension of the selenium biochemical pathways under normal physiological conditions is therefore an important issue to elucidate its effect on human diseases. This review gives an overview of the role of Se in human health highlighting the effects of its deficiency and excess in the body. The biological activity of Se, mainly performed through selenoproteins, and its epigenetic effect is discussed. Moreover, a brief overview of selenium phytoremediation and rhizofiltration approaches is reported.

SELENIUM-ASSOCIATED MECHANISMS OF PROGRESSION OF NONALCOHOLIC FATTY LIVER DISEASE IN HYPERTENSIVE PATIENTS

OBJECTIVE

The aim: To determine the role of selenium and Selenoprotein P in the intensification of inflammation processes, deviations of the functional state of the liver and the progression of changes in its parenchyma in patients with NAFLD and hypertension.

PATIENTS AND METHODS

Material and methods: Study included 100 gender and age matched NAFLD patients: 49 (67.3 % women) hypertensive (main group) and 51 (58.8 % women) non-hypertensive NAFLD patients. 20 individuals (55.0 % women) formed control group. Diagnosis of NAFLD and hypertension was made according to respective guidelines. All patients underwent measurement of liver transferases, selenium, Selenoprotein P, IL-8 and IL-10.

RESULTS

Results: In both study groups, ALT and AST levels were significantly predominant in patients with steatohepatitis than steatosis. Increase in IL-8 and IL-10 was found in main study groups but not in subgroup analysis. In hypertensive NAFLD patients with steatosis, ALT correlated with selenium and Selenoprotein P. A direct correlation was between the de Ritis index and IL-8. Selenium correlated with IL-8 but not IL-10. Selenoprotein P correlated inversely with IL-8 and directly with IL-10.

CONCLUSION

Conclusions: Intensification of inflammation and depletion of antioxidant protection under presence of hypertension deepen redox violations in NAFLD patients. Such changes can be only partially compensated by anti-inflammatory and antioxidative activity. Selenium and Selenoprotein P are important substances in progression of NAFLD and should be assessed regarding diagnosis and treatment of NAFLD patients.

Selenium Status and Its Antioxidant Role in Metabolic Diseases

Selenium (Se), in the form of selenoproteins, is an essential micronutrient that plays an important role in human health and disease. To date, there are at least 25 selenoproteins in humans involved in a wide variety of biological functions, including mammalian development, metabolic progress, inflammation response, chemoprotective properties, and most notably, oxidoreductase functions. In recent years, numerous studies have reported that low Se levels are associated with increased risk, poor outcome, and mortality of metabolic disorders, mainly related to the limited antioxidant defense resulting from Se deficiency. Moreover, the correlation between Se deficiency and Keshan disease has received considerable attention. Therefore, Se supplementation as a therapeutic strategy for preventing the occurrence, delaying the progression, and alleviating the outcomes of some diseases has been widely studied. However, supranutritional levels of serum Se may have adverse effects, including Se poisoning. This review evaluates the correlation between Se status and human health, with particular emphasis on the antioxidant benefits of Se in metabolic disorders, shedding light on clinical treatment.