Selenium, antioxidants, cardiovascular disease, and all-cause mortality: a systematic review and meta-analysis of randomized controlled trials

Selenium content in milk and dairy products: Estimation of the daily intake and assessment of the potential risk to public health

In this study, selenium levels in milk (n = 19), cheese (n = 49), yogurt (n = 13) and ayran (n = 8) of different brands sold in Türkiye were first determined by inductively coupled plasma mass spectrometry. The daily selenium intake resulting from the consumption of these foods was then calculated and evaluated with non-carcinogenic health risk. Selenium levels ranged from 9 - 32 and 1- 83 μg/L for milk and ayran, respectively, and from 0 - 224 and 12- 172 μg/kg for cheese and yogurt, respectively. The total daily selenium intake of persons aged 15> (general population) was determined to be 20.4 μg/day (0.292 μg/kg bw/day). The foods contributing most to the total daily selenium intake for all individuals in the same age group were yogurt (51.4 %), ayran (25.7 %), cheese (20.2 %) and milk (2.7 %). For individuals aged 15> (general population), the Target Hazard Quotient values resulting from the consumption of each food (milk, cheese, yogurt and ayran) and the Hazard Index value calculated by consuming all foods together (0.058) were less than 1. This study was detected any health risks related to selenium intake. This study was the first to evaluate health risks of selenium intake from consumption of some milk and dairy products in adult individuals.

Air pollution exposure and incidence of cardiometabolic diseases: Exploring the modifying role of dietary antioxidant intake in adults

While the antioxidative potential of certain vitamins and minerals in cardio-protection has garnered increasing interest, their ability to attenuate associations between air pollution exposure and cardiometabolic diseases (CMDs) remains unexplored. This study examined the associations of air pollution (particulate matter including ultrafine particles (UFP), and nitrogen oxides, including NO2 and NOx) and six dietary antioxidants with incident non-fatal CMDs in 30,519 EPIC-NL study participants. Data on CMD incidence (total cardiovascular disease (CVD), acute myocardial infarction (AMI), coronary heart disease (CHD) and heart failure (HF)) and Type 2 Diabetes Mellitus (T2DM) diagnoses were obtained from medical registries. Annual average ambient concentrations of air pollutants at the participants' baseline residential addresses were predicted using land use regression models. Dietary intake of antioxidants was assessed via a food frequency questionnaire. Multivariable Cox regression models were used to explore associations. Exposures to NO2 and UFP were associated with elevated HF risk (Hazard Ratio (HR) (95 % CI): 1.24 (1.00, 1.54) and 1.69 (1.04, 2.76), respectively). Higher beta-carotene intake was associated with reduced risk of total CVD and CHD incidence (HR (95 % CI): 0.94 (0.89, 0.99) and 0.92 (0.84, 0.99), respectively), whereas, in general, antioxidant intake was positively associated with incident T2DM. Interaction analyses indicated some variability in CMD risk by antioxidant intake, but none of these interactions remained significant after correcting for multiple comparisons. These findings indicate that the associations of air pollution with incident CMD do not differ by dietary antioxidant intake.

Associations Between Metals and Nonmetals in Drinking Water, Cardiovascular Events, and Diet

BACKGROUND

Metals and nonmetals in drinking water could potentially influence cardiovascular health. The relationship between poor-quality drinking water, major adverse cardiovascular events (MACE), and diet is not well studied.

OBJECTIVES

The aim of this study was to determine whether long-term exposure to metals (copper, manganese, aluminum, zinc, and cadmium) and nonmetals (selenium, sulfate, and nitrate-nitrogen) in drinking water was associated with MACE outcomes, and whether the dietary patterns could modify the association between long-term exposure to low-quality drinking water and MACE.

METHODS

Data from a prospective population-based cohort from Yinzhou District, Ningbo (follow-up between 2016 and 2022) were linked to Yinzhou Health Information System. MACE endpoints included acute myocardial infarction (AMI), heart failure, stroke, angina, and cardiovascular death. Effect modification of the associations between exposure and MACE by dietary factors was determined.

RESULTS

In the final cohort of 24,212 participants, 57 had an AMI; 886 developed heart failure; 733 had a stroke; 23 had angina; and 134 had a cardiovascular death. An increased risk of: 1) AMI was seen with exposure to copper, aluminum, cadmium, and selenium; 2) stroke with exposure to zinc, copper, and selenium; 3) angina with exposure to zinc and copper; and 4) cardiovascular death with exposure to zinc and aluminum in drinking water. Consuming fish, white meat, and grain products attenuated MACE outcomes induced by metals and nonmetals in drinking water.

CONCLUSIONS

In this study, long-term exposure to higher metallic and nonmetallic elements in drinking water was associated with an increased risk of MACE. Specific dietary patterns modified the associations. Further studies are needed in this area.

Exploring causal relationships between circulating micronutrients and age-related eye diseases: a Mendelian randomization study

BACKGROUND

With the global population aging, age-related eye diseases (AREDs) such as senile cataract (SC), age-related macular degeneration (AMD), glaucoma, and diabetic retinopathy (DR) are becoming increasingly significant public health concerns. The rising prevalence of AREDs underscores the urgent need for effective prevention and treatment strategies. This study aimed to explore the causal relationships between circulating micronutrients (CMs) and AREDs.

METHODS

A bidirectional two-sample Mendelian randomization (MR) analysis was conducted using genetic variants as instrumental variables to assess the effects of fifteen CMs (vitamin A, vitamin B6, vitamin B12, vitamin C, vitamin D, vitamin E, folate, carotene, copper, calcium, iron, magnesium, potassium, selenium, zinc) on AREDs. Data were sourced from large-scale genome-wide association studies (GWAS). The primary analytical method employed was inverse-variance weighted (IVW), supplemented by sensitivity analyses to confirm the robustness of the results.

RESULTS

The MR analysis revealed significant protective effects of selenium against SC (OR = 0.961, 95% CI = 0.932-0.991, P = 0.012) and DR (OR = 0.927, 95% CI = 0.870-0.987, P = 0.019). Furthermore, higher genetically predicted magnesium levels were associated with a reduced risk of AMD (OR = 0.679, 95% CI = 0.515-0.895, P = 0.006). However, no significant causal relationships were observed between the other CMs and glaucoma or other AREDs.

CONCLUSIONS

These findings provided valuable insights into the complex interplay between CMs and AREDs, offering potential pathways for developing targeted nutritional interventions and public health strategies to mitigate the risk of these debilitating conditions.

Recent research progress on the biological functions, synthesis and applications of selenium nanoparticles

Selenium is an essential trace element that is involved in a variety of complex biological processes and has a significant positive effect on the prevention and treatment of cardiovascular disease, inflammatory diseases, and cancer. Selenium in the body is mainly provided by daily meals. However, selenium has two sides, beneficial in moderation and harmful in excess. Selenium nanoparticles (SeNPs), which has better biocompatibility, safety and stability compared with other forms of selenium, is a good choice for selenium supplementing. Current researchers are exploring SeNPs in a variety of ways, including but not limited to antioxidant, antimicrobial, antiviral, inhibition of inflammation, anti-tumor, development of bio-diagnostic reagents, and nano-carrier systems. Also, efforts are being made to synthesize stable and efficient SeNPs for various applications. This study briefly describes how SeNPs are synthesized, summarizes in detail the wide range of uses of SeNPs, and provides an outlook on the future development of it. In addition, combined with the research results of our group, this study discusses the application and biological assays of SeNPs in diagnosis, which will provide inspiration and help for researchers to broaden the application of SeNPs.

Joint and independent associations of dietary antioxidant intakes with all-cause and cardiovascular mortality among patients with hypertension: a population-based cohort study

BACKGROUND

The evidence regarding dietary antioxidant intake and all-cause and cardiovascular disease (CVD) mortality among patients with hypertension is scarce.

METHODS AND RESULTS

This study included 16,190 adults with hypertension from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. Death outcomes were ascertained by linkage to National Death Index records through December 31, 2019. Overall dietary intake was estimated with composite dietary antioxidant index (CDAI). Cox proportional hazards models were used to estimate the risk for all-cause and CVD mortality. Kaplan-Meier curve was used to illustrate the survival probabilities among CDAI quartiles. Weighted quantile sum (WQS) regression was conducted to evaluate the joint and independent associations of antioxidants with all-cause and CVD mortality. The median (interquartile range) age of participants was 59.00 (47.00, 69.00) years. During a median of 94 months of follow-up, 3,858 deaths were documented. Compared to participants with the lowest quartile of CDAI, the multivariable adjusted HR and 95% CI for participants with the highest quartile was 0.76 (0.64, 0.91) for all-cause mortality. The highest quartile (Q4) of vitamin E (HR = 0.69; 95% CI, 0.59-0.80), selenium (HR = 0.84; 95% CI, 0.70-1.00) and total carotenoids (HR = 0.86; 95% CI, 0.75-0.98) intakes were negatively associated with all-cause mortality. Vitamin E and selenium intakes might be the major contributors to this negative relationship. The highest quartile (Q4) of vitamin E (HR = 0.72; 95% CI, 0.56-0.93) intake was negatively associated with CVD mortality.

CONCLUSION

Higher overall dietary antioxidant intake was significantly associated with decreased all-cause and CVD mortality among patients with hypertension. Further randomized controlled trials are required to confirm our findings.

Exploring the application of dietary antioxidant index for disease risk assessment: a comprehensive review

Oxidative stress contributes to the development of cardiometabolic diseases and cancers. Numerous studies have highlighted the adverse effects of high reactive oxygen species (ROS) levels in the progression of chronic noncommunicable diseases and also during infections. On the other hand, antioxidants play a crucial role in preventing oxidative stress or postponing cell damage via the direct scavenging of free radicals or indirectly via the Keap1/Nrf2/ARE pathway, among others. Dietary antioxidants can be obtained from various sources, mainly through a plant-based diet, including fruits and vegetables. The dietary antioxidant index (DAI) has been developed to assess total antioxidant intake from diet. This review delineated the performance of DAI in the risk assessment of different diseases. It is suggested that a high DAI score prevents obesity-related diseases, including diabetes mellitus, hyperuricemia, dyslipidemia, and metabolic (dysfunction)-associated steatotic liver disease (MASLD). Additionally, DAI is negatively associated with Helicobacter pylori and Human papillomavirus infection, thus reducing the risk of gastric and cervical cancer. Also, a high intake of antioxidants prevents the development of osteoporosis, miscarriage, infertility, and mental illnesses. However, further prospective observations and clinical trials are warranted to confirm the application of DAI in preventing diseases that have been studied.

Composite dietary antioxidant index is inversely and nonlinearly associated with cardiovascular disease, atherosclerotic cardiovascular disease, and cardiovascular mortality in people with dyslipidemia: evidence from NHANES 2001-2018

Background

Dyslipidemia is a major risk factor for cardiovascular disease (CVD) and atherosclerotic CVD (ASCVD). The composite dietary antioxidant index (CDAI), an emerging measure of combined dietary antioxidant exposure, may provide insights into the relationship between diet and CVD/ASCVD outcomes. We aimed to explore the association between CDAI and the prevalence of CVD/ASCVD, as well as CVD mortality in individuals with dyslipidemia.

Methods

CDAI was assessed by integrating dietary vitamins A, C, E, zinc, selenium, and carotenoids. Dyslipidemia was diagnosed according to widely established criteria. Data on CVD/ASCVD were obtained through self-reports, while CVD mortality was obtained through prospective matching participant records with the National Death Index database. Multivariate logistic regression analysis and Cox proportional hazards regression analysis were used to explore these associations and to calculate odds ratios [OR], hazard ratios [HR], and 95% confidence intervals [CI], respectively.

Results

A total of 23,126 participants with dyslipidemia from NHANES 2001-2018 were included. After adjusting for potential confounders, CDAI was inversely associated with the prevalence of both CVD and ASCVD in dyslipidemia populations (OR and 95% CI 0.979 (0.964, 0.995) and 0.977 (0.961, 0.993), respectively). Similar associations were observed between CDAI and specific types of CVD. CDAI was also inversely associated with CVD mortality in dyslipidemia participants (HR = 0.957, 95% CI = 0.939-0.976, p < 0.0001). Restricted cubic spline and threshold effects analyses indicated that CDAI was nonlinearly associated with CVD/ASCVD, with significant associations occurring only when CDAI≤0; however, the association of CDAI with CVD mortality was observed only when CDAI > -2. Furthermore, age, sex, and drinking were found to modify the association of CDAI with CVD/ASCVD, while body mass index influenced the relationship between CDAI and CVD mortality.

Conclusion

CDAI was inversely and nonlinearly associated with both CVD/ASCVD events and CVD mortality in dyslipidemic populations. These findings highlight the potential of antioxidant dietary patterns to alleviate the CVD burden in these populations and underscore the importance of personalized strategies.

Micronutrient Deficiencies in Heart Failure and Relationship with Exocrine Pancreatic Insufficiency

BACKGROUND

Micronutrient deficiencies are common and play a significant role in the prognosis of many chronic diseases, including heart failure (HF), but their prevalence in HF is not well known. As studies have traditionally focused on causes originating within the intestines, exocrine pancreatic insufficiency (EPI) has been overlooked as a potential contributor. The exocrine pancreas enables the absorption of various (fat-soluble) micronutrients and may be insufficient in HF. We hypothesize that EPI contributes to micronutrient deficiencies in HF.

OBJECTIVES

To evaluate micronutrient concentrations in HF cases and their association with clinical characteristics and EPI.

MATERIALS AND METHODS

Plasma samples from 59 consecutive hospitalized patients with HF were analyzed for vitamins A, D, and E and the minerals selenium and zinc. EPI was defined as fecal elastase 1 level < 206 μg/g.

RESULTS

The mean age of patients was 59 ± 14 years, with 24 (41%) being women, and a median NT-proBNP concentration of 3726 [2104-6704] pg/mL was noted. Vitamin A deficiency occurred in eight (14%) of the patients, and 12 (20%) exceeded the upper limit. More than half (51%) were vitamin D-deficient. No patients showed vitamin E deficiency, but 14 (24%) had elevated levels. Selenium deficiency was common, affecting 36 (61%) patients, while zinc was below the normal range in seven patients (12%). Micronutrient levels did not differ significantly based on the presence of EPI.

CONCLUSIONS

This study provides novel insights into the micronutrient status of patients with HF. Deficiencies in vitamins A and D, selenium, and zinc are prevalent in HF, but these findings are not associated with exocrine pancreatic function.

Effects and Impact of Selenium on Human Health, A Review

Selenium (Se) is an essential trace element that is crucial for human health. As a key component of various enzymes and proteins, selenium primarily exerts its biological functions in the form of selenoproteins within the body. Currently, over 30 types of selenoproteins have been identified, with more than 20 of them containing selenocysteine residues. Among these, glutathione peroxidases (GPXs), thioredoxin reductases (TrxRs), and iodothyronine deiodinases (DIOs) have been widely studied. Selenium boasts numerous biological functions, including antioxidant properties, immune system enhancement, thyroid function regulation, anti-cancer effects, cardiovascular protection, reproductive capability improvement, and anti-inflammatory activity. Despite its critical importance to human health, the range between selenium's nutritional and toxic doses is very narrow. Insufficient daily selenium intake can lead to selenium deficiency, while excessive intake carries the risk of selenium toxicity. Therefore, selenium intake must be controlled within a relatively precise range. This article reviews the distribution and intake of selenium, as well as its absorption and metabolism mechanisms in the human body. It also explores the multiple biological functions and mechanisms of selenium in maintaining human health. The aim is to provide new insights and evidence for further elucidating the role of selenium and selenoproteins in health maintenance, as well as for future nutritional guidelines and public health policies.

Biofortification, metabolomic profiling and quantitative analysis of vitamin B12 enrichment in guava juice via lactic acid fermentation using Levilactobacillus brevis strain KU15152

BACKGROUND

Chemical fortification and dose supplementation of vitamin B12 are widely implemented to combat deficiency symptoms. However, in situ, fortification of vitamin B12 in food matrixes can be a promising alternative to chemical fortification. The present study aimed to produce vitamin B12-rich, probiotic guava juice fermented with Levilactobacillus brevis strain KU15152. Pasteurized fresh guava juice was inoculated with 7.2 log CFU mL-1 L. brevis strain KU15152 and incubated for 72 h at 37 °C anaerobically. The antioxidants, total phenolic compounds, vitamin B12 production, sugars, organic acids, pH and viable count were analyzed at 24, 48 and 72 h of incubation. The fermented juice was stored at 4 °C, and the changes in its functional properties were analyzed at 7-day intervals up to 28 days of storage.

RESULTS

During fermentation, the bacteria cell count was increased from 7.01 ± 0.06 to 9.76 ± 0.42 log CFU mL-1 after 72 h of fermentation and was decreased to 6.94 ± 0.34 CFU mL-1 during storage at 4 °C after 28 days. The pH, total soluble solids, crude fiber, citric acid and total sugars decreased, while titratable acidity, total protein, antioxidants, phenolic compounds and lactic acid contents increased during fermentation. The fermented guava juice exhibited higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS)) radical scavenging activities (85.97% and 75.97%, respectively) at 48 h of fermentation. The concentration of active vitamin B12 in the sample reached 109.5 μg L-1 at 72 h of fermentation. However, this concentration gradually decreased to 70.2 μg L-1 during the storage period. During storage for 28 days at 4 °C, both the fermented and control guava juices exhibited a decline in antioxidant and phenolic compound concentrations. Furthermore, the addition of 20% honey and guava flavor enhanced the organoleptic properties and acceptability of fermented guava juice.

CONCLUSION

The value-added fermented guava juice could be a novel functional food product to combat vitamin B12 deficiency. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Selenium, a Notable Micronutrient: A Crucial Element in the Context of All-Cause Long-Term Mortality in Renal Failure

Selenium is a trace element involved in crucial antioxidative and anti-inflammatory processes in the body. Low selenium status has been linked to increased mortality due to compromised immune function and heightened risk of cardiovascular events. Patients with chronic kidney disease (CKD) face elevated mortality risks, prompting the need for strategies to mitigate these events. Selenium deficiency is prevalent among CKD patients, yet the long-term implications and its association with mortality in this population remain unclear. This study assessed seventy-five CKD patients' serum selenium levels (SSL) between January and February 2020. The objective was to investigate the correlation between SSL and 36-month all-cause mortality in CKD patients. Baseline laboratory values, dialysis adequacy, Charlson comorbidity index (CCI), serum selenium status, and all-cause mortality at 36 months were subjected to statistical analysis. Significance level was set at p < 0.05. Significant differences were observed in CCI between surviving and deceased groups, with deceased patients being older and afflicted with more comorbidities. SSL also exhibited a significant difference between the groups, with levels in the mortality group significantly lower than those in other patients, suggesting a potential role of selenium in predicting patient outcomes. SSL equal to or lower than 66.35 were associated with approximately 5 times higher likelihood of mortality within three years of follow-up. Our study highlights the significant association between low serum selenium levels and survival in patients with chronic kidney disease, underscoring the potential importance of selenium monitoring in this population. These findings emphasize the need for further research to elucidate the underlying mechanisms and to explore potential interventions aimed at improving outcomes in CKD patients.

Impact of Alcohol Consumption on Lifespan: a Mendelian randomization study in Europeans

Alcohol is widely used but recognized as a risk factor for several adverse health outcomes based on observational studies. How alcohol affects lifespan remains controversial, with no trial to make such an assessment available or likely. We conducted a Mendelian randomization (MR) to assess the effect of alcohol on lifespan in men and women, including a possible role of smoking and education. Strong (p < 5e- 8), independent (r2 < 0.001) genetic predictors of alcohol consumption in 2,428,851 participants of European ancestry from the Sequencing Consortium of Alcohol and Nicotine use (GSCAN) consortium genome wide association study (GWAS) were applied to sex-specific GWAS of lifespan (paternal and maternal attained age) and age at recruitment to the UK Biobank. We used multivariable MR to allow for smoking and education, with systolic and diastolic blood pressure as control outcomes. Inverse variance weighted was the primary analysis with sensitivity analysis. Alcohol consumption decreased lifespan overall (- 1.09 years (logged alcoholic drinks per week), - 1.89 to - 0.3) and in men (- 1.47 years, - 2.55 to - 0.38), which remained evident after adjusting for smoking (- 1.81 years, - 3.3 to - 0.32) and education (- 1.85 years, - 3.12 to - 0.58). Estimates from sensitivity analysis were similar, and when using the genetic variant physiologically associated with alcohol use. Alcohol consumption was associated with higher blood pressure as expected. Our study indicates that alcohol does not provide any advantages for men or women but could shorten lifespan. Appropriate interventions should be implemented.

A study on the methylation patterns of DIO3 in patients with heart failure and its correlation with key clinical parameters

Objective

This study aimed to analyze the methylation pattern of deoxyribonucleic acid (CpG) sites in the DIO3_FA26 promoter region of patients with heart failure (HF) and explore the correlation between differential CpG methylation levels and various clinical parameters.

Methods

Peripheral blood specimens were collected from 20 patients with HF and 20 healthy individuals. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to identify and detect the CpG sites in the DIO3_FA26 promoter region. CpG methylation levels were compared between patients with HF and healthy controls and patients with HF with different levels of cardiac function.

Results

The methylation level of DIO3_FA26_CpG_17.18 in patients with HF was significantly lower than that in the healthy control group (P = 0.0002). Among patients with HF and cardiac function levels of I/II and III/IV, methylation levels of DIO3_FA26_CpG_24.25.26.27 (P = 0.0168) were significantly lower in those with III/IV cardiac function compared to those with I/II cardiac function.

Conclusion

The methylation level of DIO3_FA26_CpG_17.18 is significantly reduced in patients with HF, and that of DIO3_FA26_CpG_24.25.26.27 is significantly decreased in patients with III/IV cardiac function. Variations in DIO3_FA26 methylation levels influence coagulation, liver and kidney functions, and routine blood indexes, including D-dimer, albumin, calcium, and hemoglobin. This study provides clinical evidence for the involvement of DIO3_FA26 methylation in the occurrence and development of HF and proposes novel targets for HF prevention and treatment.

High dietary antioxidant intake linked to lower risk of myocardial infarction: a nested case-control study

BACKGROUND

In developing nations, myocardial infarction (MI) remains a significant contributor to deaths from sudden cardiac arrest, with diet playing a key role in its incidence through oxidative stress mechanisms. Although the connection between the Dietary Antioxidant Index (DAI) and cardiovascular diseases has been demonstrated in some studies, the relationship between DAI and MI has not been extensively explored. Therefore, this research aims to investigate this association.

METHODS

We conducted a nested case-control study involving 156 MI cases and 312 healthy controls, utilizing data from the Fasa Adults Cohort Study (FACS), a population-based study of individuals aged 35-70 residing in Fasa, Iran, with 11,097 participants included at baseline. The DAI was determined by normalizing the intake values of six dietary vitamins and minerals, adjusting by subtracting the global mean, and then dividing by the global standard deviation. MI diagnosis was established by an experienced cardiologist using electronic medical records. Conditional logistic regression was employed to examine the association between DAI and MI.

RESULTS

There were no significant differences between the case and control groups in terms of age (P = 0.96), gender distribution (P = 0.98), and education level (P = 0.38). In a multiple conditional logistic regression analysis, after adjusting for key variables-including body mass index (BMI), smoking status, education level, and serum levels of triglycerides (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), total cholesterol (TC), fasting blood sugar (FBS), saturated fatty acids (SFA), and polyunsaturated fatty acids (PUFA)-an inverse association was found between DAI and the risk of myocardial infarction (MI) [adjusted Odds Ratio (Adj OR) = 0.88, 95% Confidence Interval (CI): 0.85-0.92; P < 0.001].

CONCLUSIONS

This study highlights the crucial role of the DAI in reducing the risk of myocardial infarction. Promoting diets rich in antioxidants presents a straightforward and effective strategy for MI prevention and the promotion of cardiovascular health, underscoring the novelty and significance of this research in dietary approaches to disease prevention.

Unlocking the biochemical secrets of longevity: balancing healthspan and lifespan

In an era of rising global life expectancies, research focuses on enhancing the quality of extended years. This review examines the link between mitochondrial function and aging, highlighting the importance of healthspan alongside lifespan. This involves significant human and economic challenges, with longer lifespans often accompanied by reduced well-being. Addressing mitochondrial decline, exploring targeted interventions, and understanding the complexities of research models are vital for advancing our knowledge in this field. Additionally, promoting physical exercise and adopting personalized supplementation strategies based on individual needs can contribute to healthy aging. The insights from this Perspective article offer a hopeful outlook for future advances in extending both lifespan and healthspan, aiming to improve the overall quality of life in aging populations.

Spectral Characteristics, In Silico Perspectives, Density Functional Theory (DFT), and Therapeutic Potential of Green-Extracted Phycocyanin from Spirulina

Phycocyanin (PC) is a naturally occurring green pigment in Spirulina. It was extracted by ultrasonic extraction using green technology, and its structure was studied using IR- and NMR-spectroscopy. Spectral data confirmed the PC structure. This study also involves an in silico assessment of the diverse applications of green pigment PC. Utilizing QSAR, PreADME/T, SwissADME, and Pro-Tox, this study explores the safety profile, pharmacokinetics, and potential targets of PC. QSAR analysis reveals a favorable safety profile, with the parent structure and most metabolites showing no binding to DNA or proteins. PreADME/T indicates low skin permeability, excellent intestinal absorption, and medium permeability, supporting oral administration. Distribution analysis suggests moderate plasma protein binding and cautious blood-brain barrier permeability, guiding formulation strategies. Metabolism assessments highlight interactions with key cytochrome P450 enzymes, influencing drug interactions. Target prediction analysis unveils potential targets, suggesting diverse therapeutic effects, including cardiovascular benefits, anti-inflammatory activities, neuroprotection, and immune modulation. Based on the in silico analysis, PC holds promise for various applications due to its safety, bioavailability, and potential therapeutic benefits. Experimental validation is crucial to elucidate precise molecular mechanisms, ensuring safe and effective utilization in therapeutic and dietary contexts. DFT calculations, including geometry optimization, MEP analysis, HOMO-LUMO energy surface, and quantum reactivity parameters of the PC compound, were obtained using the B3LYP/6-311G(d,p) level. This integrated approach contributes to a comprehensive understanding of PC's pharmacological profile and informs future research directions.

Plant Extracts for Production of Functionalized Selenium Nanoparticles

In recent years, selenium nanoparticles (SeNPs) have attracted expanding consideration, particularly in the nanotechnology field. This element participates in important biological processes, such as antioxidant defense, immune function, and thyroid hormone regulation, protecting cells from oxidative damage. Selenium in the form of nanoscale particles has drawn attention for its biocompatibility, bioavailability, and low toxicity; thus, it has found several biomedical applications in diagnosis, treatment, and monitoring. Green methods for SeNP synthesis using plant extracts are considered to be single-step, inexpensive, and eco-friendly processes. Besides acting as natural reductants, compounds from plant extracts can also serve as natural capping agents, stabilizing the size of nanoparticles and contributing to the enhanced biological properties of SeNPs. This brief overview presents the recent developments in this area, focusing on the synthesis conditions and the characteristics of the obtained SeNPs.

Selenium Species in Diabetes Mellitus Type 2

Selenium is an important trace element for humans and animals as it plays a key role in several major metabolic pathways. Several studies were conducted to better understand the role of selenium against diabetes mellitus (DM), particularly type 2 (T2DM), but the obtained conclusions are contradictory. A simple linear relationship does not exist between the risk of T2DM and selenium levels but is best represented in a dose-dependent manner, getting often the U-graph. This relation also depends on selenium chemical forms that are present in a diet or supplements. Both too low and too high selenium intakes could increase the risk of diabetes. Moreover, the baseline status of Se should be taken into consideration to avoid over-supplementation. The focus of this brief overview is to report the recent updates concerning selenium participation in diabetes mellitus.

Associations of dietary selenium intake with the risk of chronic diseases and mortality in US adults

Objective

Selenium is an essential micronutrient and a type of dietary antioxidant. This study aimed to investigate the associations of dietary selenium intake with the risk of human chronic disease [cardiovascular disease (CVD), diabetes mellitus (DM), and cancer] and mortality among US general adults.

Methods

The dietary and demographic data in this study were collected from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2018. Death outcomes were determined by associating with the National Death Index (NDI) records as of December 31, 2019. Logistic regression analyses were used to investigate the relationship of selenium intake with the risk of CVD, DM, and cancer. The effect of dietary selenium on all-cause and disease-specific mortality was estimated with restricted cubic spline (RCS) curves based on the univariate and multivariate Cox proportional hazard models.

Results

Among the 25,801 participants, dietary selenium intake was divided into quintiles (Q1-Q5). After covariate adjustment, the results showed that the participants with higher quintiles (Q4 and Q5) of selenium intake tended to have a low risk of CVD (OR = 0.97, 95% CI: 0.96, 0.99; OR = 0.98, 95% CI: 0.97, 1.00, respectively). Moreover, the RCS curves showed a significant nonlinear association between selenium intake and the risk of all-cause (with a HR of 0.82, 95% CI: 0.68, 0.99) and DM-specific mortality (with the lowest HR of 0.30; 95% CI, 0.12-0.75). Furthermore, we conducted a subgroup analysis and found a negative correlation between the highest quartile of selenium intake and all-cause mortality among participants aged 50 and above (HR = 0.75, 95% CI: 0.60-0.93, p = 0.009).

Conclusion

Our results indicated that a moderate dietary selenium supplement decreased the risk of CVD and displayed a nonlinear trend in association with the risk of all-cause and DM-specific mortality among US adults. In addition, we found that participants aged 50 and older may benefit from higher selenium intake. However, these findings still need to be confirmed through further mechanism exploration.

Selenium as a Modulator of Redox Reactions in the Prevention and Treatment of Cardiovascular Diseases

Cardiovascular diseases stand as the predominant global cause of mortality, exerting a profound impact on both life expectancy and its quality. Given their immense public health burden, extensive efforts have been dedicated to comprehending the underlying mechanisms and developing strategies for prevention and treatment. Selenium, a crucial participant in redox reactions, emerges as a notable factor in maintaining myocardial cell homeostasis and influencing the progression of cardiovascular disorders. Some disorders, such as Keshan disease, are directly linked with its environmental deficiency. Nevertheless, the precise extent of its impact on the cardiovascular system remains unclear, marked by contradictory findings in the existing literature. High selenium levels have been associated with an increased risk of developing hypertension, while lower concentrations have been linked to heart failure and atrial fibrillation. Although some trials have shown its potential effectiveness in specific groups of patients, large cohort supplementation attempts have generally yielded unsatisfactory outcomes. Consequently, there persists a significant need for further research aimed at delineating specific patient cohorts and groups of diseases that would benefit from selenium supplementation.

Prospective findings from the Dongfeng-Tongji cohort: Exposure to various metals, the expression of microRNA-4286, and the incidence of acute coronary syndrome

Mounting evidence suggests that metal/metalloid exposure is related to the adverse health effects. Our prior investigation revealed a positive relation between the plasma level of microRNA-4286 (miR-4286) and an increased risk of developing acute coronary syndrome (ACS). However, it is a lack of studies evaluating the connection between metal/metalloid exposure and miRNA expression on ACS. In the prospective Dongfeng-Tongji cohort, we performed a nested case-control study. A total of 480 ACS and 480 controls were carefully selected based on similar age, sex, and blood collection time. Using inductively coupled plasma mass spectrometry, we assessed the plasma concentrations of 24 different metals. Quantitative real-time polymerase chain reaction was used to analyze the plasma miR-4286. We examined the relations of plasma metals with miR-4286 levels, the incidence of ACS, and the potential interactions. Using the multivariate conditional logistic regression models, we observed that the adjusted odds ratios (95% confidence intervals [CI]) for incident ACS were 1.79 (1.03, 3.12; P-trend = 0.03), 0.60 (0.41, 0.87; P-trend = 0.008), and 0.66 (0.46, 0.93; P-trend = 0.02), when comparing the extreme tertiles of aluminum, rubidium, and selenium, respectively. There was a relation between the concentration of rubidium in plasma and a decrease in the level of plasma miR-4286 (percent difference [95% CI]: -13.36% [-22.74%, -2.83%]; P-trend = 0.01). Both multiplicative (P interaction = 0.009) and additive interactions (relative excess risk due to interaction [95% CI]: 0.82 [0.59, 1.06]) were noted in our observation regarding the relationship between plasma aluminum and miR-4286 in incident ACS. The findings indicated that plasma aluminum was positively while plasma rubidium and selenium were negatively linked to an increased risk of developing ACS. Plasma aluminum exposure and plasma miR-4286 expression might synergistically affect the incident ACS risk. Controlling aluminum exposure was important for ACS prevention, especially for individuals with high expression of plasma miR-4286.

FRBM Mini REVIEW: Chemogenetic approaches to probe redox dysregulation in heart failure

Chemogenetics refers to experimental methods that use novel recombinant proteins that can be dynamically and uniquely regulated by specific biochemicals. Chemogenetic approaches allow the precise manipulation of cellular signaling to delineate the molecular pathways involved in both physiological and pathological disease states. Approaches utilizing yeast d-amino acid oxidase (DAAO) enable manipulation of intracellular redox metabolism through generation of hydrogen peroxide in the presence of d-amino acids and have led to the development of new and informative animal models to characterize the impact of oxidative stress in heart failure and neurodegeneration. These chemogenetic models, in which DAAO expression is regulated by different tissue-specific promoters, have led to a range of cardiac phenotypes. This review discusses chemogenetic approaches to manipulate oxidative stress in models of heart failure. These approaches provide new insights into the relationships between redox metabolism and normal and pathologic states in the heart, as well as in other diseases characterized by oxidative stress.

Associations Between Serum Selenium and Bone Mineral Density in 8-19-year-old children and adolescents: NHANES 2013-2018

The peak bone mass (PBM) in puberty has been proven to be a critical determinant of osteoporosis and brittle fractures in the elderly. Selenium is an essential trace element that could influence bone metabolism in our bodies. However, no study has investigated the impact of selenium status on bone mineral density (BMD) among children and adolescents. This was a cross-section study from National Health and Nutrition Examination Survey (NHANES) in the USA involving participants aged 8-19 years. We conducted multiple linear regression models to assess the relationship between selenium status and BMD among children and adolescents, and then stratified analyses were performed according to genders and races. Smooth curve fits and two-piecewise linear regression models were conducted to explore their nonlinear relationship. A total of 4570 participants (2338 boys and 2232 girls) were included in the present study, with a mean age of 13.57 ± 3.41 years. In the multivariable adjustment model, serum selenium was positively associated with lumbar spine BMD (β = 0.021 95% CI: 0.008, 0.034, P = 0.001). The dose-response analyses indicated a non-linear inverted U-shaped relationship between serum selenium and lumbar spine BMD. Lower and higher selenium concentrations were related to decreased BMD, and the inflection point of serum selenium was 2.60 umol/L. The inverted U-shaped association was also observed in females (inflection point: 2.49 umol/L), males (inflection point: 2.65 umol/L), Non-Hispanic White (inflection point: 2.50 umol/L), Non-Hispanic Black (inflection point: 2.50 umol/L), and other races (Including multi-racial) (inflection point: 2.81 umol/L). Our study first shows a non-linear inversed U-shaped association between selenium status and BMD among children and adolescents. The proper selenium status will benefit bone health in children and adolescents. More research is still required to verify our findings and their potential mechanisms.

Association of composite dietary antioxidant index with depression and all-cause mortality in middle-aged and elderly population

Current research has shown an increasing acceptance of interventions for depression through dietary modifications. However, whether composite dietary antioxidant index (CDAI) is associated with depression and all-cause mortality in middle-aged and elderly population remains unknown. This study aimed to explore those associations in American middle-aged and elderly population. Weighted logistic regression models and weighted Cox proportional hazard regression models were used to assess the association of CDAI, covariates, depression, and all-cause mortality, respectively. The stability of the results was also determined by a linear trend test based on CDAI quintiles. Restricted cubic spline curves were employed to test for non-linear relationships. In the model adjusted for all covariates, significant associations were found with the ORs (95% CI) for CDAI and depression [0.77 (0.67, 0.89)] and the HRs (95% CI) for CDAI with all-cause mortality[0.91 (0.83, 1.00)]. Upon conducting restricted cubic spline curves, we found that the association between CDAI and depression was linear, whereas the association between CDAI and all-cause mortality was non-linear with an inflection point of -0.19. Statistical significance was only found before the inflection point. In this study of middle-aged and elderly Americans, CDAI was linearly negatively associated with depression and non-linearly negatively associated with all-cause mortality.

Effect of dietary selenium intake on CVD: a retrospective cohort study based on China Health and Nutrition Survey (CHNS) data

OBJECTIVE

We aimed to examine the association between dietary Se intake and CVD risk in Chinese adults.

DESIGN

This prospective cohort study included adults above 20 years old in the China Health and Nutrition Survey (CHNS), and they were followed up from 1997 to 2015 (n 16 030). Dietary data were retrieved from CHNS, and a 3-d, 24-h recall of food intake was used to assess the cumulative average intake of dietary Se, which was divided into quartiles. The Cox proportional hazards model was adopted to analyse the association between dietary Se intake and incident CVD risk.

SETTING

CHNS (1991, 1993, 1997, 2000, 2004, 2006, 2009, 2011 and 2015).

RESULTS

A total of 663 respondents developed CVD after being followed up for a mean of 9·9 years (median 9 years). The incidence of CVD was 4·3, 3·7, 4·6 and 4·0 per 1000 person-years across the quartiles of cumulative Se intake. After adjusting all potential factors, no significant associations were found between cumulative Se intake and CVD risk. No interactions were found between Se intake and income, urbanisation, sex, region, weight, hypertension and CVD risk.

CONCLUSION

We found no association between dietary Se and CVD.

Correlation between Selenium and Zinc Levels and Survival among Prostate Cancer Patients

The most prevalent type of cancer among males is prostate cancer. Survival is considered quite good, but it can be further improved when risk factors are optimized. One of these factors is micronutrients, including Se and Zn. To our knowledge, the interaction between Se and Zn and prostate cancer remains undescribed. This study aimed to investigate the optimal levels of selenium (Se) and zinc (Zn) and their impact on the survival of individuals diagnosed with prostate cancer. A total of 338 prostate cancer patients were enrolled in this study, which was conducted in Poland between 2009 and 2015. Mass spectrometry, which uses inductively coupled plasma mass, was used to assess serum element levels before treatment. The study participants were categorized into quartiles (QI-QIV) based on the distributions of Se and Zn levels observed among surviving participants. Cox regression was used to assess the association between serum Se and Zn levels and the survival of prostate cancer patients. Our results reveal the effect of combined Se and Zn levels on survival in prostate cancer patients (SeQI-ZnQI vs. SeQIV-ZnQIV; HR = 20.9). These results need further research to establish Se/Zn norms for different populations.

Association between dietary selenium intake and severe abdominal aortic calcification in the United States: a cross-sectional study

Abdominal aortic calcification (AAC) is an important predictor of cardiovascular disease. The purpose of the current study was to detect the association between dietary selenium intake and severe AAC. We included 2651 participants from the National Health and Nutrition Examination Survey (NHANES, 2013-2014). Dietary selenium intake was measured using the 24-hour recall method. AAC was quantified using the Kauppila score system based on dual-energy X-ray absorptiometry, with a score of >6 indicating severe AAC. The association between dietary selenium intake and severe AAC was analyzed by using a weighted multivariate logistic regression model, smooth curve fitting, and stratified subgroup analysis. After adjusting for multiple covariates, we found that higher dietary selenium intake was negatively associated with severe AAC incidence. When selenium intake was converted into tertiles, the highest tertile of dietary selenium intake was significantly associated with the incidence of severe AAC (odds ratio = 0.66). Smooth curve fitting revealed that this relationship was nonlinear. Subgroup analysis revealed that this negative association was present in participants with chronic kidney disease, but was absent when participants had hypertension or diabetes mellitus. Higher dietary selenium intake was negatively associated with severe AAC incidence in a nonlinear pattern, except in participants with diabetes mellitus or hypertension. However, further cohort studies are required to validate these findings.

Strong associations of serum selenoprotein P with all-cause mortality and mortality due to cancer, cardiovascular, respiratory and gastrointestinal diseases in older German adults

BACKGROUND

Selenium is an essential trace mineral. The main function of selenoprotein P (SELENOP) is to transport selenium but it has also been ascribed anti-oxidative effects.

METHODS

To assess the association of repeated measurements of serum SELENOP concentration with all-cause and cause-specific mortality serum SELENOP was measured at baseline and 5-year follow-up in 7,186 and 4,164 participants of the ESTHER study, a German population-based cohort aged 50-74 years at baseline.

RESULTS

During 17.3 years of follow-up, 2,126 study participants (30%) died. The relationship of serum SELENOP concentration with all-cause mortality was L-shaped, with mortality being significantly higher at SELENOP concentrations < 4.1 mg/L, which is near the bottom tertile's cut-off (4.2 mg/L). All-cause mortality of participants in the bottom SELENOP tertile was significantly increased compared to subjects in the top tertile (hazard ratio [95% confidence interval]: 1.35 [1.21-1.50]). SELENOP in the bottom tertile was further associated with increased cardiovascular mortality (1.24 [1.04-1.49]), cancer mortality (1.31 [1.09-1.58]), respiratory disease mortality (2.06 [1.28-3.32]) and gastrointestinal disease mortality (2.04 [1.25-3.32]). The excess risk of all-cause mortality for those in the bottom SELENOP tertile was more than twice as strong in men as in women (interaction of SELENOP and sex; p = 0.008).

CONCLUSIONS

In this large cohort study, serum SELENOP concentration was inversely associated with all-cause and cause-specific mortality. Consistent inverse associations with multiple mortality outcomes might be explained by an impaired selenium transport and selenium deficiency in multiple organs. Trials testing the efficacy of selenium supplements in subjects with low baseline SELENOP concentration are needed.

TRIAL REGISTRATION

Retrospectively registered in the German Clinical Trials Register on Feb 14, 2018 (ID: DRKS00014028).

Association of antioxidants use with the risk of dementia among community-dwelling adults in the United Kingdom biobank

Background

Data regarding the association between antioxidant supplementation and incident dementia are limited.

Methods

We included 494,632 adults (54.5% females) aged 40-71 years at baseline from the United Kingdom Biobank in the final analysis. Incident dementia was ascertained using hospital inpatient and death records up to January 2021.

Results

Over a median follow-up of 11.9 years, 7,128 new cases of all-cause dementia, 2,772 cases of Alzheimer's disease, and 1,397 cases of vascular dementia were recorded. The hazard ratio (95% CI) for incident dementia associated with zinc supplementation was 0.84 (0.74-0.96), and the association remained significant after adjusting for all confounders (0.84 (0.74-0.96)). In the full model, zinc supplementation was associated with a reduced risk of Alzheimer's disease [HR (95% CI): 0.71 (0.57-0.88)]. There was no significant association between zinc supplementation and the risk of vascular dementia. No significant associations with incident dementia were observed for other antioxidant supplementation. The association between zinc supplementation and incident dementia was significant among individuals with [HR (95% CI): 0.34 (0.15-0.77)] and without cataract [0.87 (0.77-0.99)] but it was stronger among those with cataract (p value for interaction = 0.0271).

Conclusion

Our findings suggest that zinc supplementation may help reduce the risk of all-cause dementia and Alzheimer's disease in middle-aged or older adults, especially among those with cataracts.

Non-oxidative Modified Low-density Lipoproteins: The Underappreciated Risk Factors for Atherosclerosis

Atherosclerosis, the pathological basis of most cardiovascular diseases, is a main risk factor causing about 20 million deaths each year worldwide. Oxidized low-density lipoprotein is recognized as the most important and independent risk factor in initiating and promoting atherosclerosis. Numerous antioxidants are extensively used in clinical practice, but they have no significant effect on reducing the morbidity and mortality of cardiovascular diseases. This finding suggests that researchers should pay more attention to the important role of non-oxidative modified low-density lipoprotein in atherosclerosis with a focus on oxidized low-density lipoprotein. This review briefly summarizes several important non-oxidative modified low-density lipoproteins associated with atherosclerosis, introduces the pathways through which these non-oxidative modified low-density lipoproteins induce the development of atherosclerosis in vivo, and discusses the mechanism of atherogenesis induced by these non-oxidative modified low-density lipoproteins. New therapeutic strategies and potential drug targets are provided for the prevention and treatment of atherosclerotic cardiovascular diseases.

Advances in the Synthesis and Bioactivity of Polysaccharide Selenium Nanoparticles: A Review

Selenium, an essential trace element of the human body, is pivotal in human health and disease prevention. Nevertheless, the narrow therapeutic index of selenium, where the toxic and therapeutic doses are close, limits its clinical utility. Significantly, nanoscale selenium synthesized by different methods using polysaccharides as stabilizers has low toxicity properties and exhibits excellent bioactivity. Its biological activities, such as anti-tumor, anti-inflammatory, antioxidant, antibacterial, and immune function enhancement, are improved compared with traditional organic and inorganic selenium compounds, conferring greater potential for application in biomedicine. Therefore, this review evaluates the advancements in various synthesis methodologies for polysaccharide selenium nanoparticles (Se NPs) and their biological activities. It aims to provide a comprehensive theoretical basis and research directions for the future development of highly efficient, minimally toxic, and biocompatible polysaccharide-Se NPs and the application of polysaccharide-Se NPs in biomedicine.

Selenium - a scoping review for Nordic Nutrition Recommendations 2023

Selenium is an essential trace element in humans, critical to the normal physiology in all animal species. The main form of selenium in food is selenomethionine, selenocysteine and a variety of organic compounds, while inorganic salts mainly occur in food supplements. In animals and humans, selenium occurs as selenocysteine in selenoproteins encoded by 25 genes (specific selenium pool). Several selenoproteins are part of the antioxidant enzyme system and serve as oxido-reductases and in thyroid hormone regulation. SelenoproteinP (SELENOP) transports selenium to peripheral tissues, is the main plasma selenoprotein, and has been used as biomarker of selenium status and intake. SELENOP in plasma represents a saturable pool of selenium and is maximised at a selenium concentration in plasma of about 110 µg/L or an intake of selenomethionine at about 1.2 µg/kg body weight in adults. In Finland, with an estimated selenium intake of 88 µg/day in men and 68 µg/day in women, the average selenium concentration in plasma is about 110 µg/L. Imported wheat from selenium rich areas is an important dietary source in Norway. Dietary intakes in the Nordic and Baltic area vary from 39 to 88 µg/day in men and 22 to 68 µg/day in women, the highest levels were from Finland. Most intervention trials on the effect of selenium supplementation on health outcomes have been carried out in 'selenium-replete'-populations and show no beneficial effect, which from a nutritional point of view would rather not be expected. Some intervention studies conducted in populations low in selenium have showed a beneficial effect. Observational studies suggest an inverse relationship between selenium status and risk of cardiovascular diseases (CVDs), cancer and all-cause mortality, and some other outcomes at low levels of intake (<55 µg/day) or in plasma or serum (<100 µg/L). However, a lack of quantitative data and inconsistencies between studies precludes these studies to be used to derive dietary reference values. At high intakes above 330 to 450 µg/day selenium may cause toxic effects affecting liver, peripheral nerves, skin, nails, and hair. An upper tolerable level (UL) of 255 µg selenium/day in adults was established by EFSA.

Selenium in Infants and Preschool Children Nutrition: A Literature Review

Selenium (Se), an essential trace element, is fundamental to human health, playing an important role in the formation of thyroid hormones, DNA synthesis, the immune response, and fertility. There is a lack of comprehensive epidemiological research, particularly the serum Se concetration in healthy infants and preschool children compared to the estimated dietary Se intake. However, Se deficiencies and exceeding the UL have been observed in infants and preschool children. Despite the observed irregularities in Se intake, there is a lack of nutritional recommendations for infants and preschool children. Therefore, the main objective of this literature review was to summarize what is known to date about Se levels and the risk of deficiency related to regular consumption in infants and preschool children.

Antioxidants for adults with chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is a significant risk factor for cardiovascular disease (CVD) and death. Increased oxidative stress in people with CKD has been implicated as a potential causative factor. Antioxidant therapy decreases oxidative stress and may consequently reduce cardiovascular morbidity and death in people with CKD. This is an update of a Cochrane review first published in 2012.

OBJECTIVES

To examine the benefits and harms of antioxidant therapy on death and cardiovascular and kidney endpoints in adults with CKD stages 3 to 5, patients undergoing dialysis, and kidney transplant recipients.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies until 15 November 2022 using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

We included all randomised controlled trials investigating the use of antioxidants, compared with placebo, usual or standard care, no treatment, or other antioxidants, for adults with CKD on cardiovascular and kidney endpoints.

DATA COLLECTION AND ANALYSIS

Titles and abstracts were screened independently by two authors who also performed data extraction using standardised forms. Results were pooled using random effects models and expressed as risk ratios (RR) or mean difference (MD) with 95% confidence intervals (CI). Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

We included 95 studies (10,468 randomised patients) that evaluated antioxidant therapy in adults with non-dialysis-dependent CKD (31 studies, 5342 patients), dialysis-dependent CKD (41 studies, 3444 patients) and kidney transplant recipients (21 studies, 1529 patients). Two studies enrolled dialysis and non-dialysis patients (153 patients). Twenty-one studies assessed the effects of vitamin antioxidants, and 74 assessed the effects of non-vitamin antioxidants. Overall, the quality of included studies was moderate to low or very low due to unclear or high risk of bias for randomisation, allocation concealment, blinding, and loss to follow-up. Compared with placebo, usual care, or no treatment, antioxidant therapy may have little or no effect on cardiovascular death (8 studies, 3813 patients: RR 0.94, 95% CI 0.64 to 1.40; I² = 33%; low certainty of evidence) and probably has little to no effect on death (any cause) (45 studies, 7530 patients: RR 0.95, 95% CI 0.82 to 1.11; I² = 0%; moderate certainty of evidence), CVD (16 studies, 4768 patients: RR 0.79, 95% CI 0.63 to 0.99; I² = 23%; moderate certainty of evidence), or loss of kidney transplant (graft loss) (11 studies, 1053 patients: RR 0.88, 95% CI 0.67 to 1.17; I² = 0%; moderate certainty of evidence). Compared with placebo, usual care, or no treatment, antioxidants had little to no effect on the slope of urinary albumin/creatinine ratio (change in UACR) (7 studies, 1286 patients: MD -0.04 mg/mmol, 95% CI -0.55 to 0.47; I² = 37%; very low certainty of evidence) but the evidence is very uncertain. Antioxidants probably reduced the progression to kidney failure (10 studies, 3201 patients: RR 0.65, 95% CI 0.41 to 1.02; I² = 41%; moderate certainty of evidence), may improve the slope of estimated glomerular filtration rate (change in eGFR) (28 studies, 4128 patients: MD 3.65 mL/min/1.73 m², 95% CI 2.81 to 4.50; I² = 99%; low certainty of evidence), but had uncertain effects on the slope of serum creatinine (change in SCr) (16 studies, 3180 patients: MD -13.35 µmol/L, 95% CI -23.49 to -3.23; I² = 98%; very low certainty of evidence). Possible safety concerns are an observed increase in the risk of infection (14 studies, 3697 patients: RR 1.30, 95% CI 1.14 to 1.50; I² = 3%; moderate certainty of evidence) and heart failure (6 studies, 3733 patients: RR 1.40, 95% CI 1.11 to 1.75; I² = 0; moderate certainty of evidence) among antioxidant users. Results of studies with a low risk of bias or longer follow-ups generally were comparable to the main analyses.

AUTHORS' CONCLUSIONS

We found no evidence that antioxidants reduced death or improved kidney transplant outcomes or proteinuria in patients with CKD. Antioxidants likely reduce cardiovascular events and progression to kidney failure and may improve kidney function. Possible concerns are an increased risk of infections and heart failure among antioxidant users. However, most studies were of suboptimal quality and had limited follow-up, and few included people undergoing dialysis or kidney transplant recipients. Furthermore, the large heterogeneity in interventions hampers drawing conclusions on the efficacy and safety of individual agents.

Selective Impact of Selenium Compounds on Two Cytokine Storm Players

COVID-19 patients suffer from the detrimental effects of cytokine storm and not much success has been achieved to overcome this issue. We sought to test the ability of selenium to reduce the impact of two important cytokine storm players: IL-6 and TNF-α. The effects of four selenium compounds on the secretion of these cytokines from THP-1 macrophages were evaluated in vitro following an LPS challenge. Also, the potential impact of methylseleninic acid (MSeA) on Nrf2 and IκBα was determined after a short treatment of THP-1 macrophages. MSeA was found to be the most potent selenium form among the four selenium compounds tested that reduced the levels of IL-6 and TNF-α secreted by THP-1 macrophages. In addition, an increase in Nrf2 and decrease in pIκBα in human macrophages was observed following MSeA treatment. Our data indicate that COVID-19 patients might benefit from the addition of MSeA to the standard therapy due to its ability to suppress the key players in the cytokine storm.

Low selenium intake is associated with risk of all-cause mortality in kidney transplant recipients

BACKGROUND

Deficiency of the essential trace element selenium is common in kidney transplant recipients (KTR), potentially hampering antioxidant and anti-inflammatory defence. Whether this impacts the long-term outcomes of KTR remains unknown. We investigated the association of urinary selenium excretion, a biomarker of selenium intake, with all-cause mortality; and its dietary determinants.

METHODS

In this cohort study, outpatient KTR with a functioning graft for longer than 1 year were recruited (2008-11). Baseline 24-h urinary selenium excretion was measured by mass spectrometry. Diet was assessed by a 177-item food frequency questionnaire, and protein intake was calculated by the Maroni equation. Multivariable linear and Cox regression analyses were performed.

RESULTS

In 693 KTR (43% men, 52 ± 12 years), baseline urinary selenium excretion was 18.8 (interquartile range 15.1-23.4) μg/24-h. During a median follow-up of 8 years, 229 (33%) KTR died. KTR in the first tertile of urinary selenium excretion, compared with those in the third, had over a 2-fold risk of all-cause mortality [hazard ratio 2.36 (95% confidence interval 1.70-3.28); P < .001], independent of multiple potential confounders including time since transplantation and plasma albumin concentration. The most important dietary determinant of urinary selenium excretion was protein intake (Standardized β 0.49, P < .001).

CONCLUSIONS

Relatively low selenium intake is associated with a higher risk of all-cause mortality in KTR. Dietary protein intake is its most important determinant. Further research is required to evaluate the potential benefit of accounting for selenium intake in the care of KTR, particularly among those with low protein intake.

A nutrient-wide association study for the risk of cardiovascular disease in the China Health and Nutrition Survey (CHNS) and the National Health and Nutrition Examination Survey (NHANES)

Evidence on the association between dietary nutrient-wide intake and cardiovascular disease (CVD) is inconclusive. Therefore, we systematically assessed the association between dietary intake of 29 nutrients and CVD risk using a nutrient-wide association study. Data were obtained from 7878 Chinese adults participating in the China Health and Nutrition Survey (CHNS) wave 2004-2015. We estimated the association of 29 nutrients with CVD risk. Significant findings were replicated in the National Health and Nutrition Examination Survey (NHANES). Four nutrients (selenium, vitamin A, carotenoids, and total protein) were significantly associated with CVD risk in the CHNS. The hazard ratio (HR) and 95% confidence interval (CI) for nutrient intake in the third tertile compared to the first tertile were 0.68 (0.51-0.90), 0.70 (0.54-0.91), 0.64 (0.50-0.83), and 0.54 (0.38-0.77), respectively. In the NHANES replication, selenium maintained a similar direction and strength of association, while the other nutrients were not replicated successfully. Our results provide support for a negative association between selenium intake and CVD risk, while the association of vitamin A, carotenoids and protein with CVD warrants further studies to confirm.

Perioperative selenium administration in cardiac surgery patients, a way out to reduce post surgical adversities? A meta analysis

Introduction

The oxidative damage suffered in cardiac surgery is associated with declining trace elements which lead to the development of multi organ dysfunction (MOD), acute kidney injury (AKI), or increased length of hospital stay (LOS). Recent evidence shows the cardioprotective role of the trace element selenium as it mitigates worsening outcomes post cardiac surgery. Hence, this meta analysis aims to investigate the role of selenium in lowering cardiac surgery related adverse outcomes.

Methods

Literature search of five electronic databases was performed from the inception of the paper till 29th July, 2023. Eligibility criteria included; (a) randomized clinical trials with Adult patients (≥18 years) undergoing cardiac surgery (b) intervention with selenium pre or/and postoperatively; (c) a control group of a placebo, normal saline, or no selenium. Outcomes of interest include postoperative mortality, LOS in the hospital and Intensive Care Unit (ICU), AKI, troponin I, and Creatinine Kinase-MB (CK-MB). The Cochrane bias assessment tool was used to evaluate the risk of bias. Outcomes were pooled with the Mantel-Haenszel Random-effects model using Review Manager.

Results

Seven RCTs with 2,521 patients and 65% of males were included in this paper. No noticable differences were observed between selenium and control groups in terms of postoperative AKI, mortality, LOS in hospital and ICU, troponin I, and CK-MB levels. All studies had a low risk of bias on quality assessment.

Discussion

Our meta analysis demonstrated no discernible effects of selenium infusion on post operative complications among patients undergoing cardiac surgery. Further large scale multi centered studies comparing the protective role of selenium with combined therapy of other bioactive agents are needed to provide convincing explanations.

Systematic Review Registration

PROSPERO Identifier: 424920.

Catechins and Selenium Species-How They React with Each Other

The combination of selenium and tea infusion, both with antioxidant properties, has potentially complementary mechanisms of action. Se-enriched tea has been considered as a possible Se supplement and a functional beverage to reduce the health risk of Se deficiency. This work investigated the interactions between plant catechins present in tea infusions and selenium species based on changes in the concentration of both reagents, their stability in aqueous solutions, and the possibilities of selenonanoparticles (SeNPs) formation. Selenium species exhibited instability both alone in their standard solutions and in the presence of studied catechins; selenocystine appeared as the most unstable. The recorded UV-Vis absorption spectra indicated the formation of SeNPs in the binary mixtures of catechins and selenite. SeNPs have also formed with diameters smaller than 100 nm when selenite and selenomethionine were added to tea infusions. This is an advantage from the point of view of potential medical applications.

Dose-response relationship between multiple trace elements and risk of all-cause mortality: a prospective cohort study

Objectives

We aimed to prospectively investigate the independent and combined relationship between trace elements concentrations [blood (selenium, manganese), serum (copper, zinc), and urine (cobalt, molybdenum, tin, strontium, iodine)] and all-cause mortality.

Methods

This study included 5,412 individuals with demographical, examination, and laboratory data from the National Health and Nutrition Examination Survey. Three statistical models, including Cox proportional hazards models, restricted cubic spline models, and Bayesian kernel machine regression (BKMR) models, were conducted to estimate the longitudinal relationship between trace elements and all-cause mortality.

Results

There were 356 deaths documented with a median follow-up time of 70 months. In the single-exposure model, the results showed that compared with the lowest quartile, the adjusted hazard ratios (HRs) of mortality for the highest quartile of selenium, manganese, and strontium were 0.47 (95% CI: 0.28-0.79), 1.57 (95% CI: 1.14-2.14), and 0.47 (95% CI: 0.26-0.86), respectively. A nonlinear relationship between zinc, cobalt and mortality was also observed. Furthermore, a significant overall effect of mixtures of trace elements on all-cause mortality was identified, especially when the mixture was at the 60th percentile or lower.

Conclusion

The association of multiple trace elements with all-cause mortality was identified in this study. It is recommended that healthcare providers and relevant public health agencies should strengthen the surveillance and management of trace elements. Emphasis should be placed on monitoring the sources of trace elements such as the body, food, and environment. More population studies and animal experiments should be conducted to identify the underlying mechanisms.

The Role of Selenium in Atherosclerosis Development, Progression, Prevention and Treatment

Selenium is an essential trace element that is essential for various metabolic processes, protection from oxidative stress and proper functioning of the cardiovascular system. Se deficiency has long been associated with multiple cardiovascular diseases, including endemic Keshan's disease, common heart failure, coronary heart disease, myocardial infarction and atherosclerosis. Through selenoenzymes and selenoproteins, Se is involved in numerous crucial processes, such as redox homeostasis regulation, oxidative stress, calcium flux and thyroid hormone metabolism; an unbalanced Se supply may disrupt these processes. In this review, we focus on the importance of Se in cardiovascular health and provide updated information on the role of Se in specific processes involved in the development and pathogenesis of atherosclerosis (oxidative stress, inflammation, endothelial dysfunction, vascular calcification and vascular cell apoptosis). We also discuss recent randomised trials investigating Se supplementation as a potential therapeutic and preventive agent for atherosclerosis treatment.

5-Nitrobenzo[c][1, 2, 5]selenadiazole as therapeutic agents in the regulation of oxidative stress and inflammation induced by influenza A(H1N1)pdm09 in vitro and in vivo

Currently, various problems are being faced in the treatment of influenza, so the development of new safe and effective drugs is crucial. Selenadiazole, an important component of selenium heterocyclic compounds, has received wide attention for its biological activity. This study aimed to verify the antiviral activity of 5-nitrobenzo[c][1,2,5]selenadiazole (SeD-3) in vivo and in vitro. The cell counting kit-8 assay and observation of cytopathic effect verified that SeD-3 could improve the survival of influenza A(H1N1)pdm09-infected Madin-Darby canine kidney cells. Polymerase chain reaction quantification and neuraminidase assay showed that SeD-3 could inhibit the proliferation of H1N1 virus. The time of addition assay demonstrated that SeD-3 may have a direct effect on virus particles and block some stages of H1N1 life cycle after virus adsorption. Cell cycle, JC-1, Annexin V, and terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling-4',6-diamidino-2-phenylindole (TUNEL-DAPI) assays showed that SeD-3 inhibited H1N1 infection-induced apoptosis. Cytokine detection demonstrated SeD-3 inhibited the production of proinflammatory factors after infection, including tumor necrosis factor-α (TNF-α), TNF-β, interferon-γ, interleukin 12 (IL-12), and IL-17F. In vivo experiments suggested that the pathological damage in the lungs was significantly alleviated after treatment with SeD-3 by hematoxylin and eosin staining. The TUNEL assay of lung tissues indicated that SeD-3 inhibited DNA damage during H1N1 infection. Immunohistochemical assays were performed to further explore the mechanism that SeD-3 inhibited H1N1-induced apoptosis via reactive oxygen species-mediated MAPK, AKT, and P53 signaling pathways. In conclusion, SeD-3 may become a new potential anti-H1N1 influenza virus drug due to its antiviral and anti-inflammatory activity.

Associations of composite dietary antioxidant index with cardiovascular disease mortality among patients with type 2 diabetes

To investigate the associations of composite dietary antioxidant index (CDAI) with risk of cardiovascular disease (CVD) mortality among individuals with type 2 diabetes (T2D). This prospective cohort study included 7551 patients with T2D who participated in the National Health and Nutrition Examination Survey (NHANES) from 1999 through 2018. Death statistics were gathered by connecting the cohort database to the National Death Index through December 31, 2019. Multivariable Cox proportional hazards regression models were utilized to calculate hazard ratios and 95% CIs for the relationship of CDAI with risks of CVD and all-cause mortality. Three multivariable models were built. Restricted cubic spline analyses were utilized to explore the nonlinear association of CDAI with CVD mortality, and nonlinearity was tested by the likelihood ratio test. This cohort study included data from 7551 participants with T2D (mean [SE] age, 61.4 (0.2) years; 3811 male [weighted, 50.5%] and 3740 female [weighted, 49.5%]; median CDAI level, - 2.19 [IQR, - 2.19 ~ - 0.22]). A total of 2227 all-cause deaths and 746 CVD deaths were identified during an average of 98 months of follow-up. Nonlinear associations were observed for CDAI (P < 0.05 for nonlinearity) with risk of CVD mortality among patients with T2D. Compared with participants in the first quartile of CDAI levels (< - 2.19), the hazard ratios for CVD mortality were 0.47 (95% CI 0.30-0.75) for participants in the highest CDAI level quartile. This cohort study found that higher CDAI levels were significantly associated with lower risk of CVD mortality among individuals with T2D.

Serum Essential Elements and Survival after Cancer Diagnosis

In a prospective study, we measured the associations between three serum elements (Se, Zn and Cu) and the prognosis of 1475 patients with four different types of cancer (breast, prostate, lung and larynx) from University Hospitals in Szczecin, Poland. The elements were measured in serum taken after diagnosis and prior to treatment. Patients were followed from the date of diagnosis until death from any cause or until the last follow-up date (mean years of follow-up: 6.0-9.8 years, according to site). Kaplan-Meier curves were constructed for all cancers combined and for each cancer separately. Age-adjusted hazard ratios (HRs) were estimated using Cox regression. The outcome was all-cause mortality. A Se level in the highest quartile was also associated with a reduced mortality (HR = 0.66; 95%CI 0.49-0.88; p = 0.005) in all-cause mortality for all cancers combined. Zn level in the highest quartile was also associated with reduced mortality (HR = 0.55; 95%CI 0.41-0.75; p = 0.0001). In contrast, a Cu level in the highest quartile was associated with an increase in mortality (HR = 1.91; 95%CI 1.56-2.08; p = 0.0001). Three serum elements-selenium, zinc and copper-are associated with the prognosis of different types of cancer.

Selenium Organic Content Prediction in Jengkol (Archidendron pauciflorum) and Its Molecular Interaction with Cardioprotection Receptors PPAR-γ, NF-κB, and PI3K

Selenium (Se) is a trace mineral found in plants with a distinct sulfuric odor that is cardioprotective and reported to have low toxicity. West Java, Indonesia, has a variety of plants with a distinct odor that are consumed raw, such as jengkol (Archidendron pauciflorum). This study is conducted to determine the Se content of jengkol using the fluorometric method, where the jengkol extract is separated, and the Se content is detected using high-pressure liquid chromatography (HPLC), combined with fluorometry. Two fractions with the highest Se concentration (A and B) are found and characterized using liquid chromatography mass spectrometry to predict the organic Se content by comparing the results with those in the external literature. The Se content of fraction (A) is found to be selenomethionine (m/z 198), gamma glutamyl-methyl-selenocysteine-(GluMetSeCys; m/z 313), and the Se-sulfur (S) conjugate of cysteine-selenoglutathione (m/z 475). Furthermore, these compounds are docked on receptors involved in cardioprotection. The receptors are peroxisome proliferator-activated receptor-γ (PPAR-γ), nuclear factor kappa-B (NF-κB), and phosphoinositide 3-kinase (PI3K/AKT). The interaction of receptor and ligan that has the lowest binding energy of the docking simulation is measured with molecular dynamic simulation. MD is performed to observe bond stability and conformation based on root mean square deviation, root mean square fluctuation, radius gyration, and MM-PBSA parameters. The results of the MD simulation show that the stability of the complex organic Se compounds tested with the receptors is lower than that of the native ligand, while the binding energy is lower than that of the native ligand based on the MM-PSBA parameter. This indicates that the predicted organic Se in jengkol, i.e., gamma-GluMetSeCys to PPAR-γ, gamma-GluMetSeCys AKT/PI3K, and Se-S conjugate of cysteine-selenoglutathione to NF-κB, has the best interaction results and provides a cardioprotection effect, compared to the molecular interaction of the test ligands with the receptors.

Understanding the Pathogenesis of Cardiac Complications in Patients with Propionic Acidemia and Exploring Therapeutic Alternatives for Those Who Are Not Eligible or Are Waiting for Liver Transplantation

The guidelines for the management of patients affected by propionic acidemia (PA) recommend standard cardiac therapy in the presence of cardiac complications. A recent revision questioned the impact of high doses of coenzyme Q10 on cardiac function in patients with cardiomyopathy (CM). Liver transplantation is a therapeutic option for several patients since it may stabilize or reverse CM. Both the patients waiting for liver transplantation and, even more, the ones not eligible for transplant programs urgently need therapies to improve cardiac function. To this aim, the identification of the pathogenetic mechanisms represents a key point. Aims: This review summarizes: (1) the current knowledge of the pathogenetic mechanisms underlying cardiac complications in PA and (2) the available and potential pharmacological options for the prevention or the treatment of cardiac complications in PA. To select articles, we searched the electronic database PubMed using the Mesh terms "propionic acidemia" OR "propionate" AND "cardiomyopathy" OR "Long QT syndrome". We selected 77 studies, enlightening 12 potential disease-specific or non-disease-specific pathogenetic mechanisms, namely: impaired substrate delivery to TCA cycle and TCA dysfunction, secondary mitochondrial electron transport chain dysfunction and oxidative stress, coenzyme Q10 deficiency, metabolic reprogramming, carnitine deficiency, cardiac excitation-contraction coupling alteration, genetics, epigenetics, microRNAs, micronutrients deficiencies, renin-angiotensin-aldosterone system activation, and increased sympathetic activation. We provide a critical discussion of the related therapeutic options. Current literature supports the involvement of multiple cellular pathways in cardiac complications of PA, indicating the growing complexity of their pathophysiology. Elucidating the mechanisms responsible for such abnormalities is essential to identify therapeutic strategies going beyond the correction of the enzymatic defect rather than engaging the dysregulated mechanisms. Although these approaches are not expected to be resolutive, they may improve the quality of life and slow the disease progression. Available pharmacological options are limited and tested in small cohorts. Indeed, a multicenter approach is mandatory to strengthen the efficacy of therapeutic options.

The Biochemistry and Effectiveness of Antioxidants in Food, Fruits, and Marine Algae

It is more effective to maintain good health than to regain it after losing it. This work focuses on the biochemical defense mechanisms against free radicals and their role in building and maintaining antioxidant shields, aiming to show how to balance, as much as possible, the situations in which we are exposed to free radicals. To achieve this aim, foods, fruits, and marine algae with a high antioxidant content should constitute the basis of nutritional elements, since natural products are known to have significantly greater assimilation efficiency. This review also gives the perspective in which the use of antioxidants can extend the life of food products, by protecting them from damage caused by oxidation as well as their use as food additives.

Associations between Plasma Essential Metals Levels and the Risks of All-Cause Mortality and Cardiovascular Disease Mortality among Individuals with Type 2 Diabetes

Epidemiological evidence regarding the possible link between multiple essential metals levels and all-cause mortality and cardiovascular disease (CVD) mortality among type 2 diabetes (T2D) patients is sparse. Here, we aimed to evaluate the longitudinal associations between 11 essential metals levels in plasma and all-cause mortality and CVD mortality among T2D patients. Our study included 5278 T2D patients from the Dongfeng-Tongji cohort. LASSO penalized regression analysis was used to select the all-cause and CVD mortality-associated metals from 11 essential metals (iron, copper, zinc, selenium, manganese, molybdenum, vanadium, cobalt, chromium, nickel, and tin) measured in plasma. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results: With a median follow-up of 9.8 years, 890 deaths were documented, including 312 deaths of CVD. LASSO regression models and the multiple-metals model revealed that plasma iron and selenium were negatively associated with all-cause mortality (HR: 0.83; 95%CI: 0.70, 0.98; HR: 0.60; 95%CI: 0.46, 0.77), whereas copper was positively associated with all-cause mortality (HR: 1.60; 95%CI: 1.30, 1.97). Only plasma iron has been significantly associated with decreased risk of CVD mortality (HR: 0.61; 95%CI: 0.49, 0.78). The dose-response curves for the association between copper levels and all-cause mortality followed a J shape (P_{for nonlinear} = 0.01). Our study highlights the close relationships between essential metals elements (iron, selenium, and copper) and all-cause and CVD mortality among diabetic patients.