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3.
J Coll Physicians Surg Pak ; 34(5): 561-567, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38720217

RESUMEN

OBJECTIVE: To assess the effects of selenium supplementation on blood glucose levels in women with gestational diabetes mellitus (GDM). STUDY DESIGN: Randomised controlled trial. Place and Duration of the Study: Department of Internal Medicine, Istanbul Medipol University, Faculty of Medicine, Istanbul, Turkiye, from February to July 2023. METHODOLOGY: In the first phase of this study, the selenium levels of the pregnant women who routinely had an oral glucose tolerance test were measured, and in the second phase of the study, the pregnant women diagnosed with GDM were randomly divided into two groups that received 4-week interventions: Diet alone and diet plus selenium supplementation (200 µg/day). RESULTS: Selenium level in pregnant women with GDM was significantly lower than in healthy pregnant women, and a selenium level less than 80 ng/ml predicted GDM diagnosis with a sensitivity of 58.59% and a specificity of 67.11%. Pregnant women with low selenium (<80 ng/ml) had a 2.709-fold higher risk for GDM compared to those with higher values. Fasting blood glucose levels decreased significantly in both groups after the respective interventions, but the decrease was greater in selenium recipients. Furthermore, fasting, 1st and 2nd hour blood glucose levels were lower in selenium recipients compared to those who only received diet. CONCLUSION: Selenium level in pregnant women with GDM was low compared to healthy pregnant women. Selenium supplementation had a beneficial impact (compared to diet only) on blood glucose levels in pregnant women with GDM. KEY WORDS: Pregnancy, Pregnancy outcome, Diabetes, Gestational, Dietary supplements, Selenium.


Asunto(s)
Glucemia , Diabetes Gestacional , Suplementos Dietéticos , Prueba de Tolerancia a la Glucosa , Selenio , Humanos , Diabetes Gestacional/sangre , Diabetes Gestacional/dietoterapia , Femenino , Embarazo , Selenio/sangre , Selenio/administración & dosificación , Adulto , Glucemia/metabolismo , Turquía
4.
BMC Med ; 22(1): 191, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714999

RESUMEN

BACKGROUND: Selenium-dependent deiodinases play a central role in thyroid hormone regulation and metabolism. In many European countries, insufficient selenium intake may consequently lead to adverse effects on thyroid function. In this randomised placebo-controlled double-blind study, we examined the effect of supplementation with selenium and coenzyme Q10 on thyroid hormonal status, cardiovascular (CV) mortality and health-related quality of life (Hr-QoL). METHODS: Free T3, free T4, reverse T3, and TSH were determined in 414 individuals at baseline, and the effect of selenium yeast (200 µg/day) and coenzyme Q10 (200 mg/day) supplementation on hormone concentrations, CV mortality and Hr-QoL was evaluated after 48 months using Short Form 36 (SF-36). Pre-intervention plasma selenium was low, mean 67 µg/L, corresponding to an estimated intake of 35 µg/day. Changes in concentrations of thyroid hormones following the intervention were assessed using T-tests, repeated measures of variance, and ANCOVA analyses. RESULTS: In the total population, the group with the lowest selenium concentration at baseline presented with significantly higher levels of TSH and lower levels of fT3 as compared to subjects with the highest selenium concentration. Supplementation with selenium and coenzyme Q10 for 4 years significantly increased fT3 and rT3, decreased fT4, and diminished the increase in TSH levels compared with placebo treatment (p = 0.03, all). In the placebo group, TSH and fT4 values above the median were associated with an increase in 10-year CV mortality, as compared with the mortality rate among those with TSH and fT4 below the median (p < 0.04, both), with no difference in mortality rate according to TSH and fT4 levels in the active intervention group. Similarly, TSH > median and fT3 < median were associated with a decline in mental Hr-QoL measures vs. TSH < and fT3 > median in the placebo group during 4 years of follow-up, but this was wiped out in the active group. CONCLUSIONS: Supplementation with selenium and coenzyme Q10 had a beneficial effect on thyroid hormones with respect to CV mortality and Hr-QoL outcomes. The initial deficient selenium status was associated with an impaired thyroid function and the changes in thyroid hormone levels can be explained by increased activity of deiodinases. We conclude that a substantial part of the elderly study population might suffer from suboptimal thyroidal function with adverse clinical implications due to selenium deficiency. TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov and has the identifier NCT01443780. Since it was not mandatory to register at the time the study began, the study has been registered retrospectively.


Asunto(s)
Enfermedades Cardiovasculares , Suplementos Dietéticos , Calidad de Vida , Selenio , Hormonas Tiroideas , Ubiquinona , Humanos , Ubiquinona/análogos & derivados , Ubiquinona/administración & dosificación , Ubiquinona/sangre , Selenio/administración & dosificación , Selenio/sangre , Masculino , Anciano , Femenino , Hormonas Tiroideas/sangre , Método Doble Ciego , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/sangre , Suecia/epidemiología , Anciano de 80 o más Años , Persona de Mediana Edad , Placebos/administración & dosificación
5.
Clin Interv Aging ; 19: 953-970, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38807636

RESUMEN

Purpose: This study investigated the effect of consumption of table eggs enriched with n-3 polyunsaturated fatty acids (n-3 PUFA), lutein, vitamin E and selenium on microvascular function, oxidative stress and inflammatory mediators in patients after acute coronary syndrome (ACS). Patients and Methods: In a prospective, randomized, interventional, double-blind clinical trial, ACS patients were assigned to either the Nutri4 (N=15, mean age: 57.2 ± 9.2 years), or the Control group (N=13; mean age 56.8 ± 9.6 years). The Nutri4 group consumed three enriched hen eggs daily for three weeks, providing approximately 1.785 mg of vitamin E, 0.330 mg of lutein, 0.054 mg of selenium and 438 mg of n-3 PUFAs. Biochemical parameters, including serum lipids, liver enzymes, nutrient concentrations, serum antioxidant enzyme activity (catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD)), and markers of oxidative stress (thiobarbituric acid reactive substances (TBARS) and ferric reducing ability (FRAP)), were assessed before and after the dietary interventions. Additionally, arterial blood pressure, heart rate, body composition, fluid status, anthropometric measurements, and skin microvascular blood flow responses to various stimuli (postocclusive reactive hyperemia (PORH), acetylcholine- (Ach ID), and sodium nitroprusside- (SNP ID)) were measured using laser Doppler flowmetry (LDF) throughout the study. Results: The intake of Nutri4 eggs led to a significant reduction in LDL cholesterol levels, while the levels of total cholesterol remained within the established reference values. Consuming Nutri4 eggs resulted in a 12.7% increase in serum vitamin E levels, an 8.6% increase in selenium levels, and demonstrated a favorable impact on microvascular reactivity, as evidenced by markedly improved PORH and ACh ID. Nutri4 eggs exerted a significant influence on the activity of GPx and SOD, with no observed changes in TBARS or FRAP values. Conclusion: The consumption of Nutri4 eggs positively influenced microvascular function in individuals with ACS, without eliciting adverse effects on oxidative stress.


Asunto(s)
Síndrome Coronario Agudo , Huevos , Ácidos Grasos Omega-3 , Luteína , Estrés Oxidativo , Selenio , Vitamina E , Humanos , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Femenino , Masculino , Método Doble Ciego , Estudios Prospectivos , Vitamina E/administración & dosificación , Animales , Ácidos Grasos Omega-3/administración & dosificación , Anciano , Luteína/administración & dosificación , Selenio/administración & dosificación , Antioxidantes , Endotelio Vascular/efectos de los fármacos , Superóxido Dismutasa/sangre , Pollos , Alimentos Fortificados
6.
Food Res Int ; 187: 114428, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38763678

RESUMEN

In this study, blackberry polysaccharide-selenium nanoparticles (BBP-24-3Se) were first prepared via Na2SeO3/Vc redox reaction, followed by coating with red blood cell membrane (RBC) to form core-shell structure polysaccharide-selenium nanoparticles (RBC@BBP-24-3Se). The particle size of BBP-24-3Se (167.1 nm) was increased to 239.8 nm (RBC@BBP-24-3Se) with an obvious core-shell structure after coating with RBC. FT-IR and XPS results indicated that the interaction between BBP-24-3 and SeNPs formed a new C-O···Se bond with valence state of Se0. Bioassays indicated that RBC coating markedly enhanced both the biocompatibility and bioabsorbability of RBC@BBP-24-3Se, and the absorption rate of RBC@BBP-24-3Se in HepG2 cells was 4.99 times higher than that of BBP-24-3Se at a concentration of 10 µg/mL. Compared with BBP-24-3Se, RBC@BBP-24-3Se possessed significantly heightened protective efficacy against oxidative damage and better regulation of glucose/lipid metabolism disorder induced by palmitic acid in HepG2 cells. Mechanistic studies demonstrated that RBC@BBP-24-3Se could effectively improve PI3K/AKT signaling pathway to promote glucose metabolism, inhibit the expression of lipid synthesis genes and up-regulate the expression of lipid-decomposing genes through AMPK signaling pathway to improve lipid metabolism. These results provided a theoretical basis for developing a new type of selenium supplement for the treatment of insulin resistance.


Asunto(s)
Glucosa , Metabolismo de los Lípidos , Nanopartículas , Polisacáridos , Rubus , Selenio , Humanos , Selenio/química , Células Hep G2 , Polisacáridos/farmacología , Polisacáridos/química , Metabolismo de los Lípidos/efectos de los fármacos , Glucosa/metabolismo , Nanopartículas/química , Rubus/química , Tamaño de la Partícula , Estrés Oxidativo/efectos de los fármacos , Antioxidantes/farmacología , Transducción de Señal/efectos de los fármacos
7.
Clin Nutr ESPEN ; 61: 369-376, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38777456

RESUMEN

BACKGROUND: Trace elements are an essential component of metabolism and medical nutrition therapy, with key roles in metabolic pathways, antioxidation, and immunity, which the present course aims at summarizing. RESULTS: Medical nutrition therapy includes the provision of all essential trace elements. The clinical essential issues are summarized for Copper, Iron, Selenium, Zinc, Iodine, Chromium, Molybdenum, and Manganese: the optimal analytical techniques are presented. The delivery of all these elements occurs nearly automatically when the patient is fed with enteral nutrition, but always requires separate prescription in case of parenteral nutrition. Isolated deficiencies may occur, and some patients have increased requirements, therefore a regular monitoring is required. The clinicians should always consider the impact of inflammation on blood levels, mostly lowering them even in absence of deficiency. CONCLUSION: This text summarises the most relevant clinical manifestations of trace element depletion and deficiency, the difficulties in assessing status, and makes practical recommendations for provision for enteral and parenteral nutrition.


Asunto(s)
Nutrición Enteral , Micronutrientes , Nutrición Parenteral , Oligoelementos , Humanos , Oligoelementos/deficiencia , Oligoelementos/administración & dosificación , Oligoelementos/sangre , Micronutrientes/deficiencia , Selenio/deficiencia , Selenio/sangre , Estado Nutricional , Zinc/deficiencia , Zinc/sangre , Necesidades Nutricionales , Cobre/deficiencia , Cobre/sangre , Molibdeno , Hierro/sangre
8.
Biol Pharm Bull ; 47(5): 1000-1007, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38777758

RESUMEN

Previously, insulin resistance and hepatic oxidative stress with increased expressions of glutathione peroxidase (GPx) 1 and selenoprotein P (SelP) were induced in NSY mice, a diabetic mouse model, by administrating a high fat diet (HFD) and seleno-L-methionine (SeMet) for 12 weeks. In this study we developed an analysis method for serum selenoproteins using LC-tandem mass spectrometry (LC-MS/MS) and investigated the effects of supplementary selenium on serum concentrations of selenoproteins as well as protein expression in skeletal muscle as a major insulin target tissue under the same experimental condition. The glucose area under the curves for oral glucose tolerance and insulin tolerance tests indicated that the HFD induced insulin resistance, whereas the treatment of SeMet + HFD showed insignificant promotion compared with the HFD-induced insulin resistance. Although the expressions of GPx1 in gastrocnemius and soleus were not significantly induced by supplementary SeMet nor HFD administration, the expressions of SelP in both skeletal muscles were significantly induced by the treatment of SeMet + HFD. There were also significant increases in serum concentrations of SelP by supplementary SeMet + HFD administration, whereas GPx3 was augmented by supplementary SeMet only. These results indicated that the HFD intake under the sufficient selenium status augmented the blood secretion of SelP, which may participate in the reduction of insulin sensitivity in skeletal muscles as well as liver or adipose tissues, and it is a better indicator of deterioration than GPx3 as it is a major selenoprotein in serum.


Asunto(s)
Dieta Alta en Grasa , Suplementos Dietéticos , Glutatión Peroxidasa , Resistencia a la Insulina , Músculo Esquelético , Selenio , Selenoproteínas , Animales , Músculo Esquelético/metabolismo , Músculo Esquelético/efectos de los fármacos , Masculino , Selenoproteínas/metabolismo , Dieta Alta en Grasa/efectos adversos , Ratones , Glutatión Peroxidasa/metabolismo , Glutatión Peroxidasa/sangre , Selenio/sangre , Selenio/administración & dosificación , Glutatión Peroxidasa GPX1 , Selenometionina/farmacología , Selenometionina/administración & dosificación , Selenoproteína P/sangre , Selenoproteína P/metabolismo , Modelos Animales de Enfermedad , Glucemia/metabolismo , Insulina/sangre , Espectrometría de Masas en Tándem
9.
Plant Physiol Biochem ; 211: 108673, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38733937

RESUMEN

Excess of selenium (Se) in aquatic ecosystems has necessitated thorough investigations into the effects/consequences of this metalloid on the autochthonous organisms exposed to it. The molecular details of Se-mediated adaptive response remain unknown in cyanobacteria. This study aims to uncover the molecular mechanisms driving the divergent physiological responses of cyanobacteria on exposure to selenate [Se(VI)] or selenite [Se(IV)], the two major water-soluble oxyanions of Se. The cyanobacterium, Anabaena PCC 7120, withstood 0.4 mM of Se(VI), whereas even 0.1 mM of Se(IV) was detrimental, affecting photosynthesis and enhancing endogenous ROS. Surprisingly, Anabaena pre-treated with Se(VI), but not Se(IV), showed increased tolerance to oxidative stress mediated by H2O2/methyl viologen. RNA-Seq analysis showed Se(VI) to elevate transcription of genes encoding anti-oxidant proteins and Fe-S cluster biogenesis, whereas the photosynthesis-associated genes, which were mainly downregulated by Se(IV), remained unaffected. Specifically, the content of typical 2-Cys-Prx (Alr4641), a redox-maintaining protein in Anabaena, was elevated with Se(VI). In comparison to the wild-type, the Anabaena strain over-expressing the Alr4641 protein (An4641+) showed enhanced tolerance to Se(VI) stress, whereas the corresponding knockdown-strain (KD4641) was sensitive to this stressor. Incidentally, among these strains, only An4641+ was better protected from the ROS-mediated damage caused by high dose of Se(VI). These results suggest that altering the content of the antioxidant protein 2-Cys-Prx, could be a potential strategy for modulating resistance to selenate. Thus, involvement of oxidative stress machinery appears to be the major determinant, responsible for the contrasting physiological differences observed in response to selenate/selenite in cyanobacteria.


Asunto(s)
Anabaena , Estrés Oxidativo , Estrés Oxidativo/efectos de los fármacos , Anabaena/metabolismo , Anabaena/genética , Anabaena/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Selenio/metabolismo , Selenio/farmacología , Adaptación Fisiológica/efectos de los fármacos , Ácido Selenioso/farmacología , Ácido Selenioso/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ácido Selénico/farmacología , Ácido Selénico/metabolismo , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos
10.
J Med Chem ; 67(10): 7759-7787, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38716896

RESUMEN

There is an urgent need to develop safer and more effective modalities for the treatment of a wide range of pathologies due to the increasing rates of drug resistance, undesired side effects, poor clinical outcomes, etc. Throughout the years, selenium (Se) has attracted a great deal of attention due to its important role in human health. Besides, a growing body of work has unveiled that the inclusion of Se motifs into a great number of molecules is a promising strategy for obtaining novel therapeutic agents. In the current Perspective, we have gathered the most recent literature related to the incorporation of different Se moieties into the scaffolds of a wide range of known drugs and their feasible pharmaceutical applications. In addition, we highlight different representative examples as well as provide our perspective on Se drugs and the possible future directions, promises, opportunities, and challenges of this ground-breaking area of research.


Asunto(s)
Selenio , Compuestos de Organoselenio/química , Compuestos de Organoselenio/farmacología , Selenio/química , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología
11.
Trop Anim Health Prod ; 56(4): 149, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691179

RESUMEN

Egg preference as a source of protein also provides beneficial fatty acids, vital for human consumption. However, rich in lipid products are prone to oxidative damage. The study aims to determine the effect of supplementing biogenic selenium (Se) from Stenotrophomonas maltophilia, ADS18 (ADS18) in laying hens' diet on yolk lipid oxidation status (MDA), beta-carotene (ß-carotene) content, cholesterol, fatty acids, Se, and vitamin E (VE) level. A total of one hundred and twenty (120) laying hens of Lohmann Brown strains aged 50 weeks, weighing 1500 to 2000 g were reared individually in A-shape two-tier stainless-steel cages sized 30 cm x 50 cm x 40 cm (width, depth height). The hens were randomly allotted into four treatments with six replications in a complete randomised design for the period of 12 weeks. The basal diet contains 100 mg/kg VE. Treatment diets consist of basal diet as control, SS containing 0.3 mg/kg sodium selenite, Se-yeast containing 0.3 mg/kg selenised yeast, and VADS18 containing 0.3 mg/kg of ADS18. Forty-eight eggs were collected and freeze-dried biweekly for analysis. The results of the present study showed that hens supplemented ADS18 had significantly (P < 0.05) lower MDA and cholesterol levels while their egg yolks had higher levels of Se and mono-unsaturated fatty acids (MUFA). The control group had significantly (P < 0.05) higher saturated fatty acid (SFA) contents than the VE and dietary Se-supplemented groups, while the ADS18 group had the lowest SFA contents. Conversely, in comparison to the inorganic and control groups, the VE content of the egg yolk was significantly (P < 0.05) higher in organic Se-supplemented (Se-yeast and VADS18) groups. Hens with SS supplementation had significantly (P < 0.05) higher egg yolk ß-carotene content. When compared to other treatment groups, the control group had higher (P < 0.05) polyunsaturated fatty acids (PUFA) content. The ADS18 is therefore deemed comparable to other Se sources. To prevent Se toxicity, however, a better understanding of the levels of ADS18 incorporation in poultry diets is required.


Asunto(s)
Alimentación Animal , Pollos , Dieta , Suplementos Dietéticos , Yema de Huevo , Selenio , Vitamina E , Animales , Femenino , Suplementos Dietéticos/análisis , Alimentación Animal/análisis , Selenio/administración & dosificación , Selenio/análisis , Yema de Huevo/química , Vitamina E/administración & dosificación , Vitamina E/análisis , Dieta/veterinaria , Distribución Aleatoria , Ácidos Grasos/análisis , Ácidos Grasos/metabolismo , Lípidos/análisis , beta Caroteno/análisis , beta Caroteno/administración & dosificación , beta Caroteno/metabolismo
12.
Can Vet J ; 65(5): 481-487, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38694739

RESUMEN

Background: An adequate supply of trace elements is very important for equine neonates, as deficiencies can lead to health problems and even death. Objective: This study investigated serum concentrations of selenium (Se), copper (Cu), and zinc (Zn) in neonatal foals up to the 8th day of life. The influences of disease, age, and failure of passive transfer (FPT) on these concentrations were analyzed. Animals and procedure: Serum concentrations of Se, Cu, and Zn were determined from blood samples of 93 foals by means of inductively coupled plasma mass spectrometry. The foals were divided into 2 groups based on health status: clinically sick (n = 51) and clinically healthy (n = 42). The latter group was further divided into foals with FPT (n = 20) and those without (n = 22). Results: Mean serum concentrations for Se, Cu, and Zn were 60 ± 40 µg/L, 0.25 ± 0.22 mg/L, and 605 ± 285 µg/L, respectively. A significant influence of age on serum Cu concentration was observed (P < 0.0001). No differences were observed between any of the serum concentrations in clinically sick and clinically healthy foals on the 1st day of life. The FPT status was not associated with reduced serum concentrations of Se, Cu, or Zn. Conclusion and clinical relevance: It is not necessary to supplement trace elements in all foals with FPT.


Concentrations sériques de sélénium, de cuivre et de zinc chez les poulains nouveau-nés : influence de l'échec du transfert passif et des changements liés à l'âge. Contexte: Un apport suffisant en oligo-éléments est très important pour les nouveau-nés équins, car des carences peuvent entraîner des problèmes de santé, voire la mort. Objectif: Cette étude a examiné les concentrations sériques de sélénium (Se), de cuivre (Cu) et de zinc (Zn) chez les poulains nouveau-nés jusqu'au 8ème jour de vie. Les influences de maladies, de l'âge et de l'échec du transfert passif (FPT) sur ces concentrations ont été analysées. Animaux et procédure: Les concentrations sériques de Se, Cu et Zn ont été déterminées à partir d'échantillons de sang de 93 poulains au moyen d'une spectrométrie de masse à plasma à couplage inductif. Les poulains ont été divisés en 2 groupes en fonction de leur état de santé: cliniquement malades (n = 51) et cliniquement sains (n = 42). Ce dernier groupe a été divisé en poulains avec FPT (n = 20) et ceux sans (n = 22). Résultats: Les concentrations sériques moyennes de Se, Cu et Zn étaient respectivement de 60 ± 40 µg/L, 0,25 ± 0,22 mg/L et 605 ± 285 µg/L. Une influence significative de l'âge sur la concentration sérique de Cu a été observée (P < 0,0001). Aucune différence n'a été observée entre les concentrations sériques chez les poulains cliniquement malades et cliniquement sains au premier jour de leur vie. Le statut FPT n'était pas associé à une réduction des concentrations sériques de Se, Cu ou Zn. Conclusion et pertinence clinique: Il n'est pas nécessaire de supplémenter tous les poulains en oligo-éléments avec FPT.(Traduit par Dr Serge Messier).


Asunto(s)
Animales Recién Nacidos , Cobre , Enfermedades de los Caballos , Selenio , Zinc , Animales , Caballos/sangre , Selenio/sangre , Cobre/sangre , Zinc/sangre , Animales Recién Nacidos/sangre , Enfermedades de los Caballos/sangre , Femenino , Masculino , Envejecimiento/sangre , Inmunidad Materno-Adquirida , Oligoelementos/sangre
13.
Nat Commun ; 15(1): 4041, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740794

RESUMEN

Due to the complexity of the catalytic FeMo cofactor site in nitrogenases that mediates the reduction of molecular nitrogen to ammonium, mechanistic details of this reaction remain under debate. In this study, selenium- and sulfur-incorporated FeMo cofactors of the catalytic MoFe protein component from Azotobacter vinelandii are prepared under turnover conditions and investigated by using different EPR methods. Complex signal patterns are observed in the continuous wave EPR spectra of selenium-incorporated samples, which are analyzed by Tikhonov regularization, a method that has not yet been applied to high spin systems of transition metal cofactors, and by an already established grid-of-error approach. Both methods yield similar probability distributions that reveal the presence of at least four other species with different electronic structures in addition to the ground state E0. Two of these species were preliminary assigned to hydrogenated E2 states. In addition, advanced pulsed-EPR experiments are utilized to verify the incorporation of sulfur and selenium into the FeMo cofactor, and to assign hyperfine couplings of 33S and 77Se that directly couple to the FeMo cluster. With this analysis, we report selenium incorporation under turnover conditions as a straightforward approach to stabilize and analyze early intermediate states of the FeMo cofactor.


Asunto(s)
Azotobacter vinelandii , Molibdoferredoxina , Nitrogenasa , Selenio , Azufre , Espectroscopía de Resonancia por Spin del Electrón/métodos , Azotobacter vinelandii/enzimología , Azotobacter vinelandii/metabolismo , Nitrogenasa/metabolismo , Nitrogenasa/química , Molibdoferredoxina/metabolismo , Molibdoferredoxina/química , Selenio/metabolismo , Selenio/química , Azufre/metabolismo , Azufre/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química
14.
Front Endocrinol (Lausanne) ; 15: 1362085, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38752174

RESUMEN

Background: Previous studies have identified several genetic and environmental risk factors for chronic kidney disease (CKD). However, little is known about the relationship between serum metals and CKD risk. Methods: We investigated associations between serum metals levels and CKD risk among 100 medical examiners and 443 CKD patients in the medical center of the First Hospital Affiliated to China Medical University. Serum metal concentrations were measured using inductively coupled plasma mass spectrometry (ICP-MS). We analyzed factors influencing CKD, including abnormalities in Creatine and Cystatin C, using univariate and multiple analysis such as Lasso and Logistic regression. Metal levels among CKD patients at different stages were also explored. The study utilized machine learning and Bayesian Kernel Machine Regression (BKMR) to assess associations and predict CKD risk based on serum metals. A chained mediation model was applied to investigate how interventions with different heavy metals influence renal function indicators (creatinine and cystatin C) and their impact on diagnosing and treating renal impairment. Results: Serum potassium (K), sodium (Na), and calcium (Ca) showed positive trends with CKD, while selenium (Se) and molybdenum (Mo) showed negative trends. Metal mixtures had a significant negative effect on CKD when concentrations were all from 30th to 45th percentiles compared to the median, but the opposite was observed for the 55th to 60th percentiles. For example, a change in serum K concentration from the 25th to the 75th percentile was associated with a significant increase in CKD risk of 5.15(1.77,8.53), 13.62(8.91,18.33) and 31.81(14.03,49.58) when other metals were fixed at the 25th, 50th and 75th percentiles, respectively. Conclusions: Cumulative metal exposures, especially double-exposure to serum K and Se may impact CKD risk. Machine learning methods validated the external relevance of the metal factors. Our study highlights the importance of employing diverse methodologies to evaluate health effects of metal mixtures.


Asunto(s)
Insuficiencia Renal Crónica , Humanos , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/etiología , Insuficiencia Renal Crónica/inducido químicamente , Femenino , Masculino , Persona de Mediana Edad , Modelos Teóricos , Adulto , Selenio/sangre , Factores de Riesgo , China/epidemiología , Metales Pesados/sangre , Metales Pesados/efectos adversos , Anciano , Exposición a Riesgos Ambientales/efectos adversos , Metales/sangre , Metales/efectos adversos , Aprendizaje Automático , Cistatina C/sangre , Teorema de Bayes , Potasio/sangre
15.
J Nanobiotechnology ; 22(1): 250, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750519

RESUMEN

The complexity of repairing large segment defects and eradicating residual tumor cell puts the osteosarcoma clinical management challenging. Current biomaterial design often overlooks the crucial role of precisely regulating innervation in bone regeneration. Here, we develop a Germanium Selenium (GeSe) co-doped polylactic acid (PLA) nanofiber membrane-coated tricalcium phosphate bioceramic scaffold (TCP-PLA/GeSe) that mimics the bone-periosteum structure. This biomimetic scaffold offers a dual functionality, combining piezoelectric and photothermal conversion capabilities while remaining biodegradable. When subjected to ultrasound irradiation, the US-electric stimulation of TCP-PLA/GeSe enables spatiotemporal control of neurogenic differentiation. This feature supports early innervation during bone formation, promoting early neurogenic differentiation of Schwann cells (SCs) by increasing intracellular Ca2+ and subsequently activating the PI3K-Akt and Ras signaling pathways. The biomimetic scaffold also demonstrates exceptional osteogenic differentiation potential under ultrasound irradiation. In rabbit model of large segment bone defects, the TCP-PLA/GeSe demonstrates promoted osteogenesis and nerve fibre ingrowth. The combined attributes of high photothermal conversion capacity and the sustained release of anti-tumor selenium from the TCP-PLA/GeSe enable the synergistic eradication of osteosarcoma both in vitro and in vivo. This strategy provides new insights on designing advanced biomaterials of repairing large segment bone defect and osteosarcoma.


Asunto(s)
Regeneración Ósea , Fosfatos de Calcio , Osteogénesis , Osteosarcoma , Andamios del Tejido , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/patología , Animales , Regeneración Ósea/efectos de los fármacos , Andamios del Tejido/química , Conejos , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Osteogénesis/efectos de los fármacos , Poliésteres/química , Humanos , Diferenciación Celular/efectos de los fármacos , Neoplasias Óseas/patología , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/terapia , Línea Celular Tumoral , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Células de Schwann/efectos de los fármacos , Nanofibras/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Selenio/química , Selenio/farmacología
16.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(5): 598-607, 2024 May 15.
Artículo en Chino | MEDLINE | ID: mdl-38752248

RESUMEN

Objective: To investigate the feasibility of selenium-methylselenocysteine (SMC) to promote peripheral nerve regeneration and its mechanism of action. Methods: Rat Schwann cells RSC96 cells were randomly divided into 5 groups, which were group A (without any treatment, control group), group B (adding 100 µmol/L H 2O 2), group C (adding 100 µmol/L H 2O 2+100 µmol/L SMC), group D (adding 100 µmol/L H 2O 2+200 µmol/L SMC), group E (adding 100 µmol/L H 2O 2+400 µmol/L SMC); the effect of SMC on cell proliferation was detected by MTT method, and the level of oxidative stress was detected by immunofluorescence for free radicals [reactive oxygen species (ROS)] after determining the appropriate dose group. Thirty-six 4-week-old male Sprague Dawley rats were randomly divided into 3 groups, namely, the sham operation group (Sham group), the sciatic nerve injury group (PNI group), and the SMC treatment group (SMC group), with 12 rats in each group; the rats in the PNI group were fed with food and water normally after modelling operation, and the rats in the SMC group were added 0.75 mg/kg SMC to the drinking water every day. At 4 weeks after operation, the sciatic nerves of rats in each group were sampled for neuroelectrophysiological detection of highest potential of compound muscle action potential (CMAP). The levels of inflammatory factors [interleukin 17 (IL-17), IL-6, IL-10 and oxidative stress factors catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA)] were detected by ELISA assay. The luxol fast blue (LFB) staining was used to observe the myelin density, fluorescence intensity of glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP) was observed by immunofluorescence staining, and myelin morphology was observed by transmission electron microscopy with measurement of axon diameter. Western blot was used to detect the protein expressions of p38 mitogen-activated protein kinases (p38MAPK), phosphorylated p38MAPK (p-p38MAPK), heme oxygenase 1 (HO-1), and nuclear factor erythroid 2-related factor 2 (Nrf2). Results: MTT assay showed that the addition of SMC significantly promoted the proliferation of RSC96 cells, and the low concentration could achieve an effective effect, so the treatment method of group C was selected for the subsequent experiments; ROS immunofluorescence test showed that group B showed a significant increase in the intensity of ROS fluorescence compared with that of group A, and group C showed a significant decrease in the intensity of ROS fluorescence compared with that of group B ( P<0.05). Neuroelectrophysiological tests showed that the highest potential of CMAP in SMC group was significantly higher than that in PNI and Sham groups ( P<0.05). ELISA assay showed that the levels of IL-6, IL-17, and MDA in PNI group were significantly higher than those in Sham group, and the levels of IL-10, SOD, and CAT were significantly lower; the levels of IL-6, IL-17, and MDA in SMC group were significantly lower than those in PNI group, and the levels of IL-10, SOD, and CAT were significantly higher ( P<0.05). LFB staining and transmission electron microscopy showed that the myelin density and the diameter of axons in the SMC group were significantly higher than those of the PNI group and the Sham group ( P<0.05). Immunofluorescence staining showed that the fluorescence intensity of GFAP and MBP in the SMC group were significantly stronger than those in the PNI group and Sham group ( P<0.05). Western blot showed that the relative expressions of Nrf2 and HO-1 proteins in the SMC group were significantly higher than those in the PNI group and Sham group, and the ratio of p-p38MAPK/p38MAPK proteins was significantly higher in the PNI group than that in the SMC group and Sham group ( P<0.05). Conclusion: SMC may inhibit oxidative stress and inflammation after nerve injury by up-regulating the Nrf2/HO-1 pathway, and then inhibit the phosphorylation of p38MAPK pathway to promote the proliferation of Schwann cells, which ultimately promotes the formation of myelin sheaths and accelerates the regeneration of peripheral nerves.


Asunto(s)
Regeneración Nerviosa , Estrés Oxidativo , Ratas Sprague-Dawley , Células de Schwann , Nervio Ciático , Selenio , Selenocisteína , Animales , Regeneración Nerviosa/efectos de los fármacos , Ratas , Masculino , Selenocisteína/análogos & derivados , Selenocisteína/farmacología , Células de Schwann/metabolismo , Células de Schwann/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Nervio Ciático/efectos de los fármacos , Selenio/farmacología , Proliferación Celular/efectos de los fármacos , Traumatismos de los Nervios Periféricos/metabolismo
17.
BMC Biotechnol ; 24(1): 27, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38725019

RESUMEN

Cyanobacteria represent a rich resource of a wide array of unique bioactive compounds that are proving to be potent sources of anticancer drugs. Selenium nanoparticles (SeNPs) have shown an increasing potential as major therapeutic platforms and led to the production of higher levels of ROS that can present desirable anticancer properties. Chitosan-SeNPs have also presented antitumor properties against hepatic cancer cell lines, especially the Cht-NP (Chitosan-NPs), promoting ROS generation and mitochondria dysfunction. It is proposed that magnetic fields can add new dimensions to nanoparticle applications. Hence, in this study, the biosynthesis of SeNPs using Alborzia kermanshahica and chitosan (CS) as stabilizers has been developed. The SeNPs synthesis was performed at different cyanobacterial cultivation conditions, including control (without magnetic field) and magnetic fields of 30 mT and 60 mT. The SeNPs were characterized by uv-visible spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), Dynamic light scattering (DLS), zeta potential, and TEM. In addition, the antibacterial activity, inhibition of bacterial growth, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC), as well as the antifungal activity and cytotoxicity of SeNPs, were performed. The results of uv-visible spectrometry, DLS, and zeta potential showed that 60 mT had the highest value regarding the adsorption, size, and stabilization in compared to the control. FTIR spectroscopy results showed consistent spectra, but the increased intensity of peaks indicates an increase in bond number after exposure to 30 mT and 60 mT. The results of the antibacterial activity and the inhibition zone diameter of synthesized nanoparticles showed that Staphylococcus aureus was more sensitive to nanoparticles produced under 60 mT. Se-NPs produced by Alborzia kermanshahica cultured under a 60 mT magnetic field exhibit potent antimicrobial and anticancer properties, making them a promising natural agent for use in the pharmaceutical and biomedical industries.


Asunto(s)
Quitosano , Campos Magnéticos , Selenio , Selenio/química , Selenio/farmacología , Quitosano/química , Quitosano/farmacología , Humanos , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/biosíntesis , Pruebas de Sensibilidad Microbiana , Nanopartículas/química , Antineoplásicos/farmacología , Antineoplásicos/metabolismo , Antineoplásicos/química , Nanopartículas del Metal/química
18.
BMC Geriatr ; 24(1): 415, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730347

RESUMEN

BACKGROUND: Parkinson's disease (PD) is a slowly progressive neurodegenerating disease that may eventually lead to disabling condition and pose a threat to the health of aging populations. This study aimed to explore the association of two potential risk factors, selenium and cadmium, with the prognosis of Parkinson's disease as well as their interaction effect. METHODS: Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 2005-2006 to 2015-2016 and National Death Index (NDI). Participants were classified as Parkinson's patients by self-reported anti-Parkinson medications usage. Cox regression models and restricted cubic spline models were applied to evaluate the association between PD mortality and selenium intake level as well as blood cadmium level. Subgroup analysis was also conducted to explore the interaction between them. RESULTS: A total of 184 individuals were included. In full adjusted cox regression model (adjusted for age, gender, race, hypertension, pesticide exposure, smoking status and caffeine intake), compared with participants with low selenium intake, those with normal selenium intake level were significantly associated with less risk of death (95%CI: 0.18-0.76, P = 0.005) while no significant association was found between low selenium intake group and high selenium group (95%CI: 0.16-1.20, P = 0.112). Restricted cubic spline model indicated a nonlinear relationship between selenium intake and PD mortality (P for nonlinearity = 0.050). The association between PD mortality and blood cadmium level was not significant (95%CI: 0.19-5.57, P = 0.112). However, the interaction term of selenium intake and blood cadmium showed significance in the cox model (P for interaction = 0.048). Subgroup analysis showed that the significant protective effect of selenium intake existed in populations with high blood cadmium but not in populations with low blood cadmium. CONCLUSION: Moderate increase of selenium intake had a protective effect on PD mortality especially in high blood cadmium populations.


Asunto(s)
Cadmio , Enfermedad de Parkinson , Selenio , Humanos , Cadmio/sangre , Masculino , Femenino , Enfermedad de Parkinson/sangre , Enfermedad de Parkinson/mortalidad , Selenio/sangre , Selenio/administración & dosificación , Estudios Retrospectivos , Anciano , Persona de Mediana Edad , Encuestas Nutricionales/métodos , Factores de Riesgo , Dieta , Causas de Muerte/tendencias , Estudios de Cohortes
19.
Nutrients ; 16(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38732573

RESUMEN

The role of selenium in the developmental process of esophageal cancer (EC) requires further investigation. To explore the relationship between selenium-related factors and EC through bioinformatic analysis, a case-control study was conducted to verify the results. Utilizing the GEPIA and TCGA databases, we delineated the differential expression of glutathione peroxidase 3 (GPx3) in EC and normal tissues, identified differentially expressed genes (DEGs), and a performed visualization analysis. Additionally, 100 pairs of dietary and plasma samples from esophageal precancerous lesions (EPLs) of esophageal squamous cancer (ESCC) cases and healthy controls from Huai'an district, Jiangsu, were screened. The levels of dietary selenium, plasma selenium, and related enzymes were analyzed using inductively coupled plasma mass spectrometry (ICP-MS) or ELISA kits. The results showed lower GPx3 expression in tumor tissues compared to normal tissues. Further analysis revealed that DEGs were mainly involved in the fat digestion and absorption pathway, and the core protein fatty acid binding protein 1 (FABP1) was significantly upregulated and negatively correlated with GPx3 expression. Our case-control study found that selenium itself was not associated with EPLs risk. However, both the decreased concentration of GPx3 and the increase in FABP1 were positively correlated with the EPLs risk (p for trend = 0.035 and 0.046, respectively). The different expressions of GPx3 and FABP1 reflect the potential of selenium for preventing ESCC at the EPLs stage. GPx3 may affect myocardial infarction through FABP1, which remains to be further studied.


Asunto(s)
Biología Computacional , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Proteínas de Unión a Ácidos Grasos , Glutatión Peroxidasa , Selenio , Humanos , Selenio/sangre , Glutatión Peroxidasa/genética , Glutatión Peroxidasa/metabolismo , Glutatión Peroxidasa/sangre , Estudios de Casos y Controles , Neoplasias Esofágicas/prevención & control , Neoplasias Esofágicas/genética , Biología Computacional/métodos , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Carcinoma de Células Escamosas de Esófago/prevención & control , Carcinoma de Células Escamosas de Esófago/genética , Femenino , Masculino , Persona de Mediana Edad , Regulación Neoplásica de la Expresión Génica , Anciano
20.
Nutrients ; 16(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38732577

RESUMEN

BACKGROUND: Cadmium (Cd) is an environmental contaminant that poses risks to human and animal health. Selenium (Se), a beneficial element, alleviates the detrimental consequences of colitis and Cd toxicity. Se is found in food products as both inorganic Se (sodium selenite) and organic Se (typically Se-enriched yeast). Nano-selenium (nano-Se; a novel form of Se produced through the bioreduction of Se species) has recently garnered considerable interest, although its effects against Cd-induced enterotoxicity are poorly understood. The aim of this study was to investigate the impact of nano-selenium on mitigating cadmium toxicity and safeguarding the integrity of the intestinal barrier. METHODS: For a total of two cycles, we subjected 6-week-old C57 mice to chronic colitis by exposing them to Cd and nano-selenium for two weeks, followed by DSS water for one week. RESULTS: The application of nano-selenium mitigated the intensity of colitis and alleviated inflammation in the colon. Nano-selenium enhanced the diversity of the intestinal flora, elevated the concentration of short-chain fatty acids (SCFAs) in feces, and improved the integrity of the intestinal barrier. CONCLUSIONS: In summary, nano-Se may reduce intestinal inflammation by regulating the growth of intestinal microorganisms and protecting the intestinal barrier.


Asunto(s)
Cadmio , Colitis , Microbioma Gastrointestinal , Ratones Endogámicos C57BL , Selenio , Animales , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Selenio/farmacología , Microbioma Gastrointestinal/efectos de los fármacos , Ratones , Colon/efectos de los fármacos , Colon/metabolismo , Colon/microbiología , Masculino , Enfermedad Crónica , Modelos Animales de Enfermedad , Nanopartículas , Ácidos Grasos Volátiles/metabolismo , Heces/microbiología , Sulfato de Dextran , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología
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