Vitamin D Deficiency: Effects on Oxidative Stress, Epigenetics, Gene Regulation, and Aging

Vitamin D deficiency attenuates endothelial function by reducing antioxidant activity and vascular eNOS expression in the rat microcirculation

This study examined the effects of vitamin D deficiency on vascular function and tissue oxidative status in the microcirculation; and whether or not these effects can be ameliorated with calcitriol, the active vitamin D metabolite. Three groups (n = 10 each) of male Sprague Dawley rats were fed for 10 weeks with control diet (CR), vitamin D-deficient diet without (DR), or with oral calcitriol supplementation (0.15 μg/kg) for the last four weeks (DSR). After 10 weeks, rats were sacrificed; mesenteric arterial rings were studied using wire myograph. Oxidative stress biomarkers malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity were measured in the mesenteric arterial tissue. Vascular protein expression of endothelial nitric oxide synthase (eNOS) was determined by Western blotting. Acetylcholine-induced endothelium-dependent relaxation of DR was lower than CR. eNOS expression and SOD activity were lower in mesenteric arterial tissue of DR compared to CR. Calcitriol supplementation to DSR did not ameliorate the above parameters; in fact, augmented endothelium-dependent contraction was observed. Serum calcium was higher in DSR compared to CR and DR. In conclusion, vitamin D deficiency impaired microvascular vasodilation, associated with eNOS downregulation and reduced antioxidant activity. Calcitriol supplementation to vitamin D-deficient rats at the dosage used augmented endothelium-dependent contraction, possibly due to hypercalcaemia.

Antioxidant supplementations ameliorate PCOS complications: a review of RCTs and insights into the underlying mechanisms

Polycystic ovary syndrome (PCOS) is one of the most important gynecological disorders of women in the age of reproduction. Different hormonal and inflammatory cross-talks may play in the appearance of its eventual complications as a leading cause of infertility. Excessive production of reactive oxygen species over the power of the antioxidant system as oxidative stress is known to contribute to a variety of diseases like PCOS. Thus, the utilization of antioxidants can be efficient in preventing or assistant in treating these diseases. In this review, we describe the clinical trial studies that have examined the efficiency of antioxidant strategies against PCOS and the possible underlying mechanisms. The investigations presented here lead us to consider that targeting oxidative stress pathways is probably a powerful promising therapeutic approach towards PCOS. There is preparatory evidence of the effectiveness of antioxidant interventions in ameliorating some of the PCOS complications, including metabolic and hormonal disorders. Due to limited data and relatively few clinical trials, many of these interventions need further investigation before they can be considered effective agents for routine clinical use.

Effect of Exercise Training on 1,25(OH)2D Levels: The FIT-AGEING Randomized Controlled Trial

BACKGROUND

Vitamin D deficiency is currently endemic worldwide and is considered as an important factor in the development of several chronic conditions. Physical exercise has been postulated as an auspicious strategy to counteract age-related disorders preventing premature mortality. However, the effects of chronic exercise training on 1,25-dihydroxyvitamin D [1,25(OH)₂D] is unclear. This 12-week randomized controlled trial aimed to investigate the effects of different training modalities on 1,25(OH)₂D in healthy sedentary adults.

HYPOTHESIS

Exercise training will increase 1,25(OH)₂D in the study cohort.

STUDY DESIGN

Randomized controlled clinical trial.

LEVEL OF EVIDENCE

Level 1.

METHODS

A total of 89 healthy sedentary adults (53% women; 53.5 ± 4.9 years old) were enrolled in the FIT-AGEING study. The participants were randomized to (1) a control group (no exercise), (2) physical activity recommendation from the World Health Organization (PAR group), (3) high-intensity interval training (HIIT group), and (4) HIIT adding whole-body electromyostimulation training (HIIT + EMS). 1,25(OH)₂D plasma levels were measured using a DiaSorin Liaison immunochemiluminometric analyzer.

RESULTS

Compared with the control group, 1,25(OH)₂D increased in PAR (Δ = 10.99 ± 3.44 pg/mL; P = 0.01), HIIT (Δ = 11.63 ± 3.51 pg/mL; P = 0.009), and HIIT + EMS groups (Δ = 14.01 ± 3.59 pg/mL; P = 0.001) without statistical differences between them (all Ps > 0.1).

CONCLUSION

In summary, the results show that a 12-week exercise intervention produced an increment of 1,25(OH)₂D independently of age, sex, and exercise modality in healthy sedentary adults.

CLINICAL RELEVANCE

The implementation of physical exercise could be considered a strategy not only aiming to reverse the seasonal decrease of 1,25(OH)₂D in winter explained by low sunlight exposure but also for obtaining subsequent increases of this hormone even in these a priori adverse conditions.

Prevalence and Clinical Outcomes of Vitamin D Deficiency in COVID-19 Hospitalized Patients: A Retrospective Single-Center Analysis

Vitamin D attenuates inflammatory responses to viral respiratory infections. Hence, vitamin D deficiency may be a highly significant prognostic factor for severity and mortality in COVID-19 patients. To evaluate the complications and mortality in different vitamin D status groups in COVID-19 hospitalized patients, we conducted this retrospective study on 646 laboratory-confirmed COVID-19 patients who were hospitalized in Shahid Modarres Hospital, Tehran, Iran from 16th March 2020 until 25th February 2021. Overall, patients with vitamin D deficiency, insufficiency and sufficiency were 16.9%, 43.6% and 39.5%, respectively. The presence of comorbidity, length of hospitalization, ICU admission, and invasive mechanical ventilation requirement and overall complications were significantly more in patients with vitamin D deficiency (p-value < 0.001). 46.8% (51/109) of vitamin D deficient patients died due to the disease, whilst the mortality rate among insufficient and sufficient vitamin D groups was 29.4% (83/282) and 5.5% (14/255), respectively. In univariate analysis, age > 60 years (odds ratio (OR) = 6.1), presence of comorbidity (OR = 10.7), insufficient vitamin D status (OR = 7.2), and deficient vitamin D status (OR = 15.1) were associated with increase in COVID-19 mortality (p-value < 0.001). Finally, the multivariate analysis adjusted for age, sex, and comorbidities indicated vitamin D deficiency as an independent risk factor for mortality (OR = 3.3, p-value = 0.002). Vitamin D deficiency is a strong risk factor for mortality and severity of SARS-CoV-2 infection. Vitamin D supplementation may be able to prevent or improve the prognosis of COVID-19 during this pandemic.

Vitamin D status and systemic redox biomarkers in adults with obesity

BACKGROUND & AIMS

Vitamin D has been proposed to have a protective role against oxidative stress. The present study was conducted to test the hypothesis that suboptimal levels of 25(OH)D are related to oxidative/antioxidative biomarkers in adults independently of obesity.

METHODS

In this case-control study, 140 subjects with obesity and 90 age- and sex-matched 25(OH)D sufficient normal weight controls were selected. Subjects with obesity were categorized as 25(OH)D sufficient, insufficient, and deficient based on their serum 25(OH)D concentrations. Serum malondialdehyde (MDA), total oxidant status (TOS), and total antioxidant capacity (TAC) as well as erythrocytes superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) along with serum paraoxonase-1 (PON1) and arylesterase (AREase) activities were assessed.

RESULTS

Serum concentrations of 25(OH)D were inversely correlated with BMI, WC, fat mass, and visceral fat. Serum levels of MDA and TOS, and erythrocyte SOD activities were significantly higher, whereas, serum TAC, PON1, and AREase were significantly lower in subjects with obesity compared to the controls (p < 0.0001). 25(OH)D deficient obese subjects exhibited higher serum levels of MDA as well as erythrocyte SOD activity (p < 0.05) and lower serum levels of TAC (p < 0.0001), PON1 (p < 0.05), and AREase (p < 0.0001) compared to obese subjects with 25(OH)D sufficiency and controls even when adjusted for BMI.

CONCLUSIONS

The present findings demonstrated a strong association between the severity of 25(OH)D deficiency and oxidative/antioxidative related parameters independently of obesity.

Effect of 25-hydroxyvitamin D and essential oil complex on productive performance, egg quality, and uterus antioxidant capacity of laying hens

This study was conducted to determine the effect of 25-hydroxyvitamin D (HDV) and essential oils (EO) on the uterus antioxidant capacity, egg quality, and eggshell ultrastructure in laying hens. A total of 400 48-wk-old Lohmann laying hens were randomly allocated into 2 groups and fed a basal diet (control) or a basal diet supplemented with a combination of 69 μg/kg HDV and EO (including 200 mg/kg thymol and 50 mg/kg carvacrol) for 12 wk. There are 10 replicates of 20 hens each. Compared with the control, dietary HDV+EO supplementation improved (P < 0.05) egg production rate, feed efficiency, eggshell thickness and strength, and decreased (P < 0.05) the translucent egg score. Ultrastructural changes indicated that dietary HDV+EO supplementation decreased (P < 0.05) mammillary knob width, mammillary thickness and the proportion of mammillary thickness, and increased (P < 0.05) the proportion of effective thickness and total thickness of the eggshells compared with the control. Supplementation with HDV+EO complex led to higher serum HDV concentration and increased antioxidant capacity in the uterus, indicated by higher (P < 0.05) antioxidant enzyme activities (catalase [CAT], total antioxidant capacity [T-AOC], and glutathione S-transferases [GST]) and lower malondialdehyde (MDA) content. Therefore, dietary HDV and EO complex (including thymol and carvacrol) supplementation can improve the productive performance and the eggshell quality in laying hens, and the improving effect on eggshell quality may through enhancing eggshell ultrastructure and antioxidant capacity of uterus.

Vitamin D and COVID-19: A review on the role of vitamin D in preventing and reducing the severity of COVID-19 infection

Severe Acute Respiratory Syndrome Coronavirus‐2 (SARS‐CoV‐2) is a pathogenic coronavirus causing COVID‐19 infection. The interaction between the SARS‐CoV‐2 spike protein and the human receptor angiotensin‐converting enzyme 2, both of which contain several cysteine residues, is impacted by the disulfide‐thiol balance in the host cell. The host cell redox status is affected by oxidative stress due to the imbalance between the reactive oxygen/nitrogen species and antioxidants. Recent studies have shown that Vitamin D supplementation could reduce oxidative stress. It has also been proposed that vitamin D at physiological concentration has preventive effects on many viral infections, including COVID‐19. However, the molecular‐level picture of the interplay of vitamin D deficiency, oxidative stress, and the severity of COVID‐19 has remained unclear. Herein, we present a thorough review focusing on the possible molecular mechanism by which vitamin D could alter host cell redox status and block viral entry, thereby preventing COVID‐19 infection or reducing the severity of the disease.

Muscle Regeneration and Function in Sports: A Focus on Vitamin D

Muscle is one of the main targets for the biological effects of vitamin D. This hormone modulates several functions of skeletal muscles, from development to tissue repair after injury, through genomic and non-genomic mechanisms. Vitamin D deficiency and supplementation seem to significantly affect muscle strength in different populations, including athletes, although optimal serum 25(OH)D3 level for sport performance has not been defined so far. Additionally, vitamin D deficiency results in myopathy characterized by fast-twitch fiber atrophy, fatty infiltration, and fibrosis. However, less is known about regenerative effects of vitamin D supplementation after sport-related muscle injuries. Vitamin D receptor (VDR) is particularly expressed in the embryonic mesoderm during intrauterine life and in satellite cells at all stages of life for recovery of the skeletal muscle after injury. Vitamin D supplementation enhances muscle differentiation, growth, and regeneration by increasing the expression of myogenic factors in satellite cells. The objective of this narrative review is to describe the role of vitamin D in sport-related muscle injury and tissue regeneration.

Immunostimulant and Antidepressant Effect of Natural Compounds in the Management of Covid-19 Symptoms

In recent years, the use of natural compounds as adjuvant treatments and alternatives to traditional pharmacological therapies has become increasingly popular. These compounds have a wide range of biological effects, such as: antioxidant, anti-aging, hypocholesterolizing, hypoglycemic, antitumoral, antidepressant, anxiolytic activity, etc. Almost all of these compounds are easily available and are contained in different foods. At the end of 2019 the Coronavirus SARS-CoV-2 appeared in China and quickly spread throughout the world, causing a pandemic. The most common symptoms of this infection are dry cough, fever, dyspnea, and in severe cases bilateral interstitial pneumonia, with consequences that can lead to death. The nations, in trying to prevent the spread of infection, have imposed social distancing and lockdown measures on their citizens. This had a strong psychological-social impact, leading to phobic, anxious and depressive states. Pharmacological therapy could be accompanied by treatment with several natural compounds, such as vitamins, baicalein, zinc and essential oils. These compounds possess marked immunostimulant activity, strengthening the immune response and mitigating interactions between the virus and the host cell. They also have an antidepressant effect, acting on certain neurotransmitters.

Analysis of the Impact of Selected Vitamins Deficiencies on the Risk of Disability in Older People

Vitamin deficiencies have a serious impact on healthy aging in older people. Many age-related disorders have a direct or indirect impact on nutrition, both in terms of nutrient assimilation and food access, which may result in vitamin deficiencies and may lead to or worsen disabilities. Frailty is characterized by reduced functional abilities, with a key role of malnutrition in its pathogenesis. Aging is associated with various changes in body composition that lead to sarcopenia. Frailty, aging, and sarcopenia all favor malnutrition, and poor nutritional status is a major cause of geriatric morbidity and mortality. In the present narrative review, we focused on vitamins with a significant risk of deficiency in high-income countries: D, C, and B (B6/B9/B12). We also focused on vitamin E as the main lipophilic antioxidant, synergistic to vitamin C. We first discuss the role and needs of these vitamins, the prevalence of deficiencies, and their causes and consequences. We then look at how these vitamins are involved in the biological pathways associated with sarcopenia and frailty. Lastly, we discuss the critical early diagnosis and management of these deficiencies and summarize potential ways of screening malnutrition. A focused nutritional approach might improve the diagnosis of nutritional deficiencies and the initiation of appropriate clinical interventions for reducing the risk of frailty. Further comprehensive research programs on nutritional interventions are needed, with a view to lowering deficiencies in older people and thus decreasing the risk of frailty and sarcopenia.

Relationship between 25 Hydroxyvitamin D, Overweight/Obesity Status, Pro-Inflammatory and Oxidative Stress Markers in Patients with Type 2 Diabetes: A Simplified Empirical Path Model

Vitamin D deficiency is highly prevalent in patients with overweight/obesity and type 2 diabetes (T2DM). Herein, we investigated the relationship between vitamin D status and overweight/obesity status, insulin resistance (IR), systemic inflammation as well as oxidative stress (OS). Anthropometric and laboratory assessments of 25-hydroxyvitamin D (25(OH)D) and glycemic, pro-inflammatory and OS biomarkers were performed in a sample of 47 patients with T2DM who were divided into categories based on overweight and degree of obesity. The main findings were: the overweight/obesity status correlated negatively with the degree of serum 25(OH)D deficiency (ρ = −0.27) with a trend towards statistical significance (p = 0.069); the homeostasis model assessment of insulin resistance (HOMA-IR) was significantly different (p = 0.024) in patients with 25(OH)D deficiency, as was total oxidant status (TOS) and oxidative stress index (OSI) in patients with severe serum 25(OH)D deficiency as compared to those with 25(OH)D over 20 ng/mL (TOS: p = 0.007, OSI: p = 0.008); and 25(OH)D had a negative indirect effect on TOS by body mass index (BMI), but BMI was not a significant mediator of the studied relationship. In a setting of overweight and increasing degree of obesity, patients with T2DM did not display decreasing values of 25(OH)D. Subjects with the lowest values of 25(OH)D presented the highest values of BMI. Patients with 25(OH)D deficiency were more insulin resistant and showed increased OS but no elevated systemic inflammation. The negative effect of 25(OH)D on TOS did not seem to involve BMI as a mediator.

Vitamin D Deficiency, Osteoporosis and Effect on Autoimmune Diseases and Hematopoiesis: A Review

Vitamin D (VD) is essential for bone homeostasis, but it is also involved in pleiotropic effects on various organs and tissues. In adults, VD deficiency can cause or exacerbate osteoporosis and induce osteomalacia. However, every tissue and cell in the body has a VD receptor, including the brain, heart, stomach, pancreas, skin, gonads, and immune cells, and a deficiency may modify the function of these organs. Thus, the wide-ranging actions of VD help to explain why a reduction in VD amount has been correlated with numerous chronic diseases. In fact, VD deficiency increases the risk of osteoporosis and several other diseases and complications characterized by impaired bone metabolisms, such as autoimmune diseases, inflammatory bowel diseases, allergy, endocrinological diseases, hematological malignancies, and bone marrow transplantation. This review aims to investigate the link between VD deficiency, osteoporosis, and its concomitant diseases. Further epidemiological and mechanistic studies are necessary in order to ascertain the real role of hypovitaminosis in causing the reported diseases; however, adequate vitamin supplementation and restoration of metabolic normality could be useful for better management of these pathologies.

Associations of Vitamin D Levels with Physical Fitness and Motor Performance; A Cross-Sectional Study in Youth Soccer Players from Southern Croatia

Simple Summary

Vitamin D is a fat-soluble prohormone crucial for bone mineralization, muscle contractility, and neurological conductivity. It is theorized that Vitamin D plays an important role in sport performances, especially in young athletes. In this study we examined the associations of levels of 25-hydroxyvitamin D (25(OH)D) with physical fitness and motor-performance achievements in youth soccer players from Southern Croatia. Participants were tested on physical fitness, motor performance and vitamin D at the end of the winter period, when levels of vitamin D are known to be lowest due to low exposure to sunlight. Results showed that deficiency of 25(OH)D was widespread among youth soccer players living in Southern Croatia. Low 25(OH)D levels were associated with lower results in fitness tests (i.e., tests of energetic capacities), but there was no correlation between 25(OH)D levels and the results in motor performance tests (i.e., skill tests). Our results support the theory of the association between vitamin D and energetic capacities of athletes, but there is no evidence on association between vitamin D and skill-based capacities.

Abstract

Vitamin D level is known to be a factor potentially influencing physical fitness, but few studies have examined this phenomenon among youth athletes. We aimed to evaluate the associations of vitamin D levels (as measured by 25-hydroxyvitamin D concentrations—25(OH)D) with various physical fitness and motor performance tests in youth football (soccer) players. This cross-sectional study included a total of 52 youth soccer players (15.98 ± 2.26 years old) from Southern Croatia. The participants were evaluated at the end of the winter period and data were collected of anthropometric measures (body mass and body height), vitamin D status (25(OH)D levels), physical fitness tests (sprints of 10 and 20 m, 20 yards test, the countermovement jump, the reactive strength index (RSI)) and motor performance tests (the soccer-specific CODS, the soccer-specific agility, and static balance). Among the studied players, 54% had 25(OH)D insufficiency/deficiency, showing a lack of 25(OH)D is widespread even in youth athletes living at a southern latitude. The 25(OH)D level was correlated with sprint 20 m, 20 yards tests, and RSI, showing a greater role of 25(OH)D in physical fitness tests where energetic capacity is essential than in sport-related motor performance tests where skills are crucial. Our results support the idea that vitamin D can play a determinant role in physical fitness tests with a clear physiological component, but is not crucial in motor performance tests related to specific sports where skills are a key component. Future studies should investigate the effects of vitamin D supplementation on the performance in physical fitness and motor performance tests among youth athletes.

Comparative study on beneficial effects of vitamins B and D in attenuating doxorubicin induced cardiotoxicity in rats: Emphasis on calcium homeostasis

The use of doxorubicin (DOX) to treat various tumors is limited by its cardiotoxicity. This study aimed to investigate and compare the cardioprotective effects of nicotinamide (NAM) and alfacalcidol (1α(OH)D3), against DOX-induced cardiotoxicity. Sprague Dawley male rats received DOX (5 mg/kg, i.p.) once/week for four consecutive weeks. Treated groups received either NAM (600 mg/kg, p.o.) for 28 consecutive days or 1α(OH)D3 (0.5 ug/kg, i.p.) once/week for four consecutive weeks. DOX elicited marked cardiac tissue injury manifested by elevated serum cardiotoxicity indices, conduction and histopathological abnormalities. Both NAM and 1α(OH)D3 successfully reversed all these changes. From the mechanistic point of view, DOX provoked intense cytosolic and mitochondrial calcium (Ca2+) overload hence switching on calpain1 (CPN1) and mitochondrial-mediated apoptotic cascades as confirmed by upregulating Bax and caspase-3 while downregulating Bcl-2 expression. DOX also disrupted cardiac bioenergetics as evidenced by adenosine triphosphate (ATP) depletion and a declined ATP/ADP ratio. Moreover, DOX upregulated the Ca2+ sensor; calmodulin kinase II gamma (CaMKII-δ) which further contributed to cardiac damage. Interestingly, co-treatment with either NAM or 1α(OH)D3 reversed all DOX associated abnormalities by preserving Ca2+ homeostasis, replenishing ATP stores and obstructing apoptotic events. Additionally, DOX prompted nuclear factor kappa B (NF-κB) dependent inflammatory responses and subsequently upregulated interleukin-6 (IL-6) expression. Co-treatment with NAM or 1α(OH)D3 effectively obstructed these inflammatory signals. Remarkably, NAM showed superior beneficial cardioprotective properties over 1α(OH)D3. Both NAM and 1α(OH)D3 efficiently attenuated DOX-cardiomyopathy mainly via preserving Ca2+ homeostasis and diminishing apoptotic and inflammatory pathways. NAM definitely exhibited effective cardioprotective capabilities over 1α(OH)D3.

Human Placental Transcriptome Reveals Critical Alterations in Inflammation and Energy Metabolism with Fetal Sex Differences in Spontaneous Preterm Birth

A well-functioning placenta is crucial for normal gestation and regulates the nutrient, gas, and waste exchanges between the maternal and fetal circulations and is an important endocrine organ producing hormones that regulate both the maternal and fetal physiologies during pregnancy. Placental insufficiency is implicated in spontaneous preterm birth (SPTB). We proposed that deficits in the capacity of the placenta to maintain bioenergetic and metabolic stability during pregnancy may ultimately result in SPTB. To explore our hypothesis, we performed a RNA-seq study in male and female placentas from women with SPTB (<36 weeks gestation) compared to normal pregnancies (≥38 weeks gestation) to assess the alterations in the gene expression profiles. We focused exclusively on Black women (cases and controls), who are at the highest risk of SPTB. Six hundred and seventy differentially expressed genes were identified in male SPTB placentas. Among them, 313 and 357 transcripts were increased and decreased, respectively. In contrast, only 61 differentially expressed genes were identified in female SPTB placenta. The ingenuity pathway analysis showed alterations in the genes and canonical pathways critical for regulating inflammation, oxidative stress, detoxification, mitochondrial function, energy metabolism, and the extracellular matrix. Many upstream regulators and master regulators important for nutrient-sensing and metabolism were also altered in SPTB placentas, including the PI3K complex, TGFB1/SMADs, SMARCA4, TP63, CDKN2A, BRCA1, and NFAT. The transcriptome was integrated with published human placental metabolome to assess the interactions of altered genes and metabolites. Collectively, significant and biologically relevant alterations in the transcriptome were identified in SPTB placentas with fetal sex disparities. Altered energy metabolism, mitochondrial function, inflammation, and detoxification may underly the mechanisms of placental dysfunction in SPTB.

Calcitriol attenuates the cytotoxicity induced by aluminium phosphide via inhibiting mitochondrial dysfunction and oxidative stress in rat isolated cardiomyocytes

These days, poisoning with aluminium phosphide (AlP), is one of the main health threats in human societies. Previous studies have been reported that cardiotoxicity induced by AlP, via mitochondrial dysfunction and oxidative stress is the main cause of death in victims. On the other, collectively, multiple lines of evidence strongly suggest that calcitriol has mitochondrial protective and antioxidant effects. Therefore, we assumed that calcitriol could presumably ameliorate AlP-induced oxidative stress and mitochondrial dysfunction in cardiomyocytes. Mitochondria and cardiomyocytes were isolated by differential centrifugation and collagenase perfusion respectively from rat heart. The isolated cardiomyocytes and mitochondria were cotreated with different concentrations of calcitriol (0.2, 0.4 and 1 μg/ml) and AlP (20 μg/ml) for 3 h. The parameters of cellular toxicity including; cytotoxicity, reactive oxygen species (ROS) formation, malondialdehyde (MDA) level, mitochondria membrane potential (ΔΨm) collapse, lysosomal membrane integrity, the level of oxidized and reduced glutathione (GSH and GSSG), and mitochondrial toxicity parameters including; succinate dehydrogenase (SDH) activity and mitochondrial swelling were analyzed using biochemical and flow cytometric evaluations. Administration of AlP significantly increased cytotoxicity, GSH depletion, cellular ROS formation, MDA level, mitochondrial and lysosomal dysfunction in isolated cardiomyocytes. In isolated mitochondria, AlP decreased SDH activity and mitochondrial swelling. The cotreatment of isolated cardiomyocytes and mitochondria with calcitriol (0.4 and 1 μg/ml) and AlP (20 μg/ml) showed the ability to reduce the toxic effects of AlP. These findings suggest a potential therapeutic role of calcitriol in protecting cardiomyocytes and cardiac mitochondria from oxidative damage induced by AlP. According to the results, calcitriol exerted ameliorative effects against AlP-induced cytotoxicity and mitochondrial toxicity, and the effect was attributed to the antioxidant properties.

Vitamin D: A Pleiotropic Hormone with Possible Psychotropic Activities

BACKGROUND

After the recognition of the efficacy of cod-liver oil in rickets at the end of the eighteenth century, and the isolation and synthesis of the liposoluble vitamin D in 1931, its mode of actions and functions were deeply explored. Biochemical studies permitted to identify five forms of vitamin D, called D1, D2, D3, D4 and D5, differing in ultrastructural conformation and origin, with vitamin D2 (ergocalciferol) and D3 (cholecalciferol) representing the active forms. In the last decades especially, a constantly increasing bulk of data highlighted how vitamin D could regulate several activities and processes.

AIMS

The aim of the present paper was to review and comment on the literature on vitamin D, with a focus on its possible role in the pathophysiology of neuropsychiatric disorders.

DISCUSSION

Available literature indicates that vitamin D regulates a variety of processes in humans and in the central nervous system. Vitamin D deficiency is associated with an enhanced pro-inflammatory state, and formation of Aβ oligomers that might contribute to the cognitive decline typical of the elderly age and, perhaps, dementia. More in general, vitamin D is supposed to play a crucial role in neuroinflammation processes that are currently hypothesized to be involved in the pathophysiology of different psychiatric disorders, such as major depression, bipolar disorders, obsessive-compulsive disorders and psychosis.

CONCLUSION

It is conceivable that vitamin D supplementation might pave the way towards "natural" treatments of a broad range of neuropsychiatric disorders, or at least be useful to boost response to psychotropic drugs in resistant cases.

High antibody levels against human herpesvirus-6A interact with lifestyle factors in multiple sclerosis development

BACKGROUND

Infection with human herpesvirus 6A (HHV-6A) has been suggested to increase multiple sclerosis (MS) risk. However, potential interactions between HHV-6A and environmental/lifestyle risk factors for MS have not previously been studied.

METHODS

We used two Swedish population-based case-control studies comprising 5993 cases and 5995 controls. Using logistic regression models, subjects with different HHV-6A antibody levels, environmental exposures, and lifestyle habits were compared regarding MS risk, by calculating odds ratios (ORs) with 95% confidence intervals (CIs). Potential interactions between high HHV-6A antibody levels and common environmental exposures and lifestyle factors were evaluated on the additive scale.

RESULTS

High HHV-6A antibody levels were associated with increased risk of developing MS (OR = 1.5, 95% CI = 1.4-1.6). Regarding MS risk, significant interactions were observed between high HHV-6A antibody levels and both smoking (attributable proportion (AP) = 0.2, 95% CI = 0.1-0.3), low ultraviolet radiation (UVR) exposure (AP = 0.3, 95% CI = 0.1-0.4), and low vitamin D levels (AP = 0.3, 95% CI = 0.0-0.6).

CONCLUSION

High HHV-6A antibody levels are associated with increased MS risk and act synergistically with common environmental/lifestyle risk factors for MS. Further research is needed to investigate potential mechanisms underlying the interactions presented in this study.

Vitamin D3 attenuates doxorubicin-induced senescence of human aortic endothelial cells by upregulation of IL-10 via the pAMPKα/Sirt1/Foxo3a signaling pathway

The toxicity of doxorubicin to the cardiovascular system often limits its benefits and widespread use as chemotherapy. The mechanisms involved in doxorubicin-induced cardiovascular damage and possible protective interventions are not well-explored. Using human aortic endothelial cells, we show vitamin D3 strongly attenuates doxorubicin-induced senescence and cell cycle arrest. We further show the protective effects of vitamin D3 are mediated by the upregulation of IL-10 and FOXO3a expression through fine modulation of pAMPKα/SIRT1/FOXO3a complex activity. These results have great significance in finding a target for mitigating doxorubicin-induced cardiovascular toxicity.

The association of vitamin D with survival in colorectal cancer patients depends on antioxidant capacity

BACKGROUND

Vitamin D plays a role in detoxifying free radicals, which might explain the previously reported lower mortality in colorectal cancer (CRC) patients with higher vitamin D concentrations.

OBJECTIVES

We aimed to assess whether the associations of 25-hydroxyvitamin D [25(OH)D] with prognosis in CRC patients differ by total thiol concentration (TTC), a biomarker of antioxidant capacity.

METHODS

CRC patients who were diagnosed from 2003 to 2010 and recruited into a population-based study in southern Germany (n = 2,592) were followed over a period of 6 y. 25(OH)D and TTC were evaluated from blood samples collected shortly after CRC diagnosis. Associations of 25(OH)D with all-cause and CRC mortality according to TTC were estimated using multivariable Cox proportional hazards regression.

RESULTS

There was a weak positive correlation between 25(OH)D and TTC (r = 0.26, P < 0.001). 25(OH)D was inversely associated with mortality among patients in the lowest and middle TTC tertiles, but no associations were found among patients in the highest TTC tertile (P-interaction = 0.01). Among patients in the lowest/middle TTC tertiles, those in the middle and highest (compared with lowest) 25(OH)D tertiles had 31% and 44% lower all-cause mortality (P < 0.001) and 25% and 45% lower CRC mortality (P < 0.001), respectively. However, in the highest TTC tertile, 25(OH)D was not associated with all-cause (P = 0.638) or CRC mortality (P = 0.395).

CONCLUSIONS

The survival advantages in CRC patients with adequate vitamin D strongly depend on antioxidant capacity and are most pronounced in cases of low antioxidant capacity. These findings suggest that TTC and other biomarkers of antioxidant status may be useful as the basis for enhanced selection criteria of patients for vitamin D supplementation, in addition to the conventional judgment based on blood 25(OH)D concentrations, and also for refining selection of patients for clinical trials aiming to estimate the effect of vitamin D supplementation.

Effects of vitamin D-induced supernatant of placental explants from preeclamptic women on oxidative stress and nitric oxide bioavailability in human umbilical vein endothelial cells

The study evaluated the effect of the supernatant of placental explants from preeclamptic (PE) and normotensive (NT) pregnant women after tissue treatment with or without vitamin D (VD) on oxidative stress and nitric oxide (NO) bioavailability in human umbilical vein endothelial cells (HUVEC). Placental explants were prepared from eight NT and eight PE women, and supernatants were obtained after incubation with or without hydrogen peroxide (H₂O₂) and/or VD. HUVEC were cultured for 24 h with supernatants, and the following parameters were analyzed in HUVEC cultures: NO, nitrate (NO₃^-), and nitrite (NO₂^-) levels, lipid peroxidation, and intracellular reactive oxygen species (ROS). Results showed that the production of NO₃^-, NO₂^-, malondialdehyde (MDA), and ROS were significantly higher in HUVEC treated with explant supernatant from PE compared to NT pregnant women, while the supernatant of PE explants treated with VD led to a decrease in these parameters. A significantly high production of NO was detected in HUVEC cultured with control supernatant of NT group, and in cultures treated with supernatant of PE explants treated with VD. Taken together, these results demonstrated that cultures of placental explants from PE women with VD treatment generated a supernatant that decreased oxidative stress and increased the bioavailability of NO in endothelial cells.

Effects of 1,25 Dihydroxyvitamin D3 on Human Retinal Pigment Epithelial Cell Lines

PURPOSE

To assess the effects of 1,25 dihydroxyvitamin D₃ (vitamin D₃) either alone or under oxidative damage on human retinal pigment epithelium cell lines.

METHODS

The human retinal pigment epithelial cell lines were pretreated with hydrogen peroxide with different concentrations (100-1000 μM) and durations (4, 12 and 24 h) to determine the appropriate dose. A group of cells were treated with vitamin D₃ alone, and another group of cells were co-treated with different concentrations of (10-100 nM) vitamin D₃ and hydrogen peroxide. Anti-cytotoxic, anti-apoptotic and anti-genotoxic effects of vitamin D₃ on the hydrogen peroxide treated cell line were evaluated. In addition, mitochondrial membrane potentials of treated cell lines were measured.

RESULTS

Vitamin D₃ showed statistically significant anti-cytotoxic effects and increased cell viability in all concentrations (p < 0.001). It has also significantly decreased the intracellular ROS generation at concentrations between 10-60 nM and increased intracellular reactive oxygen species in high doses over 90 nM (p < 0.01). When apoptosis was evaluated, vitamin D₃ caused statistically significant decrease in a dose-dependent manner (p < 0.001). In terms of DNA damage which was caused by oxidative stress, it was observed that vitamin D₃ significantly reduced the damage in a dose-dependent manner (p < 0.001). At the doses of 10-50 nM, vitamin D₃ significantly decreased the mitochondrial membrane potential (p < 0.01).

CONCLUSION

Our study suggests that 1,25 (OH)₂ D3 is capable for alleviating the oxidative damage in ARPE cell lines. With these results, vitamin D is thought to be a therapeutic alternative for the prevention of age-related macular degeneration. This warrants further investigations.

Vitamin D, Chronic Migraine, and Extracranial Pain: Is There a Link? Data From an Observational Study

Several studies focused on the role of vitamin D (vitD) in pain chronification. This study focused on vitD level and pain chronification and extension in headache disorders. Eighty patients with primary headache underwent neurological examination, laboratory exams, including serum calcifediol 25(OH)D, and headache features assessment along with three questionnaires investigating depression, anxiety, and allodynia. The 86.8% of the population had migraine (48% episodic and 52% chronic). The 44.1% of patients had extracranial pain, and 47.6% suffered from allodynia. A vitD deficit, namely a serum 25(OH)D level <20 ng/ml, was detectable in 46.1% of the patients, and it occurred more frequently (p = 0.009) in patients suffering from chronic migraine (CM)–medication overuse migraine (MOH) (62.9%) than in episodic migraine (EM, 25.7%) or tension-type headache (TTH, 11.4%). The occurrence of extracranial pain and allodynia was higher in the CM-MOH than in the EM and in the TTH groups but was not related to the co-occurrence of vitD deficiency (Fisher's exact test p = 0.11 and p = 0.32, respectively). Our findings show that 25(OH)D deficit is also related to chronic headache, probably because of vitD anti-inflammatory and tolerogenic properties, reinforcing the idea of a neuroinflammatory mechanism underpinning migraine chronification.

Maternal diet and offspring telomere length: a systematic review

CONTEXT

Many studies assert a negative influence of inappropriate maternal diet and nutritional status during pregnancy on offspring, not only in utero but throughout life, because of the role in the programing of noncommunicable diseases. Telomere length is a biomarker of aging, and shorter telomeres are associated with chronic disease later in life. Maternal nutrition and nutritional status may be an important determinant of offspring telomere length.

OBJECTIVE

A systematic review was conducted to determine the effect of maternal nutrition and nutritional status in pregnancy on offspring telomere length.

DATA SOURCES

This systematic review was conducted according to PRISMA guidelines. Database searches of PubMed, CINAHL, Scopus, Medline, and Web of Science were performed.

STUDY SELECTION

Included studies assessed the association between maternal nutrition (dietary intake and nutritional status) during pregnancy and offspring telomere length measured in cord blood, serum, plasma, and peripheral blood mononuclear cells.

DATA EXTRACTION

Three authors screened and determined the quality of the articles; disagreements were resolved by a fourth author. All authors compared the compiled data.

RESULTS

Seven studies were extracted and evaluated. Studies comprised a double-blind placebo-controlled trial (n = 1), prospective cohort studies (n = 5), and a cross-sectional study (n = 1). Higher circulating maternal folate and 25-hydroxyvitamin D3 concentrations, along with higher maternal dietary caffeine intakes, were associated with longer offspring telomere length, whereas higher dietary intake of carbohydrate, folate, n-3 polyunsaturated fatty acids, vitamin C, or sodium was not.

CONCLUSION

The limited but suggestive evidence highlights the need for further research to be conducted in this area, particularly longitudinal studies involving larger cohorts of pregnant women.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42019136506.

Vitamin D and Microbiota: Is There a Link with Allergies?

There is increasing recognition of the importance of both the microbiome and vitamin D in states of health and disease. Microbiome studies have already demonstrated unique microbial patterns in systemic autoimmune diseases such as inflammatory bowel disease, rheumatoid arthritis, and systemic lupus erythematosus. Dysbiosis also seems to be associated with allergies, in particular asthma, atopic dermatitis, and food allergy. Even though the effect of vitamin D supplementation on these pathologies is still unknown, vitamin D deficiency deeply influences the microbiome by altering the microbiome composition and the integrity of the gut epithelial barrier. It also influences the immune system mainly through the vitamin D receptor (VDR). In this review, we summarize the influence of the microbiome and vitamin D on the immune system with a particular focus on allergic diseases and we discuss the necessity of further studies on the use of probiotics and of a correct intake of vitamin D.

Synergistic Effects of Exercise Training and Vitamin D Supplementation on Mitochondrial Function of Cardiac Tissue, Antioxidant Capacity, and Tumor Growth in Breast Cancer in Bearing-4T1 Mice

Both regular exercise training and vitamin D consumption are beneficial for patients with cancer. The study investigated the effects of interval exercise training (IET) or/and vitamin D supplementation on the gene expression involved in mitochondrial function of heart tissue, tumor size, and total antioxidant capacity (TAC) in breast cancer (BC) model mice. We assigned random 40 female NMRI mice to five equal groups (n = 8); the healthy control group (H.C), cancer control group (Ca.C), cancer with the vitamin D group (Ca.VD), cancer exercise group (Ca.Ex), and cancer exercise along with the vitamin D group (Ca.Ex.VD). Forty-eight hours after treatment, we anesthetized the animals and performed the isolation of heart tissue and blood serum for further studies. The results showed that the lowest mean body weight at the end of the treatments was related to Ca.C (p = 0.001). Vitamin D treatment alone has increased tumor volume growth by approximately 23%; in contrast, co-treatment with exercise and vitamin D inhibited tumor growth in mice (P = 0.001), compared with the cancer control (12%). TAC levels were higher in the group that received both vitamin D and exercise training (Ca.Ex.VD) than in the other treatment groups (Ca.VD and Ca.Ex) (p = 0.001). In cardiac tissue, vitamin D treatment induces an elevation significantly of the mRNA expression of Pgc1-α, Mfn-1, and Drp-1 genes (p = 0.001). The study has shown the overexpression of vitamin D in female mice, and synergistic effects of IET with vitamin D on weight loss controlling, antitumorigenesis, improvement of antioxidant defense, and the modulation of gene expression. The synergistic responses were likely by increasing mitochondrial fusion and TAC to control oxidative stress. We recommended being conducted further studies on mitochondrial dynamics and biogenesis focusing on risk factors of cardiovascular disease (CVD) in patients with BC.

Effect of Vitamin D Status on Vascular Function of the Aorta in a Rat Model of PCOS

Polycystic ovary syndrome (PCOS) is associated with elevated cardiovascular risk. Early vascular dysfunction may lead to the development of cardiovascular disease in PCOS. Vitamin D deficiency (VDD) is a common comorbidity of PCOS that contributes to the pathogenesis of the disease and its complications. Both PCOS and VDD are accompanied by increased oxidative stress that may be involved in the arising vascular dysfunction. We aimed to investigate the role of vitamin D status on aortic function. PCOS was induced by an 8-week-long transdermal testosterone treatment of female rats, and low and adequate vitamin D status was achieved by dietary means. Contraction and relaxation abilities of isolated aortic segments were measured by myograph. Resorcin-fuchsin staining and immunohistochemical labeling of 3-nitrotyrosine were performed. No difference was shown in the norepinephrine-induced contraction of the aortas of different groups, whereas we detected reduced acetylcholine- and insulin-evoked relaxation in VDD groups. A lower level of resorcin-fuchsin staining and elevated 3-nitrotyrosine immunostaining was observed in VDD. In our study, we demonstrated early endothelial dysfunction in VDD PCOS rat model. Vitamin D supplementation could prevent vascular disturbances, while VDD itself damaged endothelium-dependent vasorelaxation and induced nitrative stress.

Dietary 25-hydroxyvitamin D improves intestinal health and microbiota of laying hens under high stocking density

The high stocking density is a major stress factor that adversely affects the health and performance of poultry. Therefore, the object of this study was conducted to explore whether dietary 25-hydroxyvitamin D (25-OH-D₃) could improve gut health of laying hens reared under high stocking density. A 2 × 2 factorial design was used in this 16-week study, in which 800 45-week-old Lohmann laying hens were allocated into two levels of dietary 25-OH-D₃ levels (0 and 69 µg/kg) and two rates of stocking densities [506 (low density, LD) and 338 (high density, HD) cm²/hen]. Compared with the layers with LD, the layers with HD had lower crypt depth in duodenum (P_(Density) < 0.05), lower short chain fatty acid (propionic and butyric acid) contents in cecum (P_(Density) < 0.05), and lower mRNA expression of intestinal barrier associated protein (claudin-1, mucin-1 and mucin-2). Exposed layer to HD also led to lower intestinal antioxidative capacity [superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (T-AOC), and higher malondialdehyde (MDA) content] in small intestine (P_(Density) < 0.05), lower bacterial abundance of Bacteroidetes (phylum), Spirochaetes (phylum) and Bacteroides (genus; P_(Density) < 0.05), higher bacterial enrichment of Lactobacillaceae (genus) and Firmicutes/Bacteroidetes ratio (P_(Density) < 0.05) in cecum. Dietary 25-OH-D₃ increased the villus height in duodenum and jejunum (P_(25-OH-D3) < 0.05), decreased Chao 1 and ACE indexes in cecum (P_(25-OH-D3) < 0.05), and it also up-regulated the mRNA expression of claudin-1, mucin-1 and mucin-2 (P_(25-OH-D3) < 0.05). Layers treated with 25-OH-D₃ led to an enhanced antioxidative enzyme activity of CAT (P_(25-OH-D3) < 0.05). Additionally, the effect of 25-OH-D₃ reversed the effect of HD on T-AOC and MDA content (P_{(Interaction)} < 0.05). In HD layers, 25-OH-D₃ administration decreased the enrichment of Bacteroidetes (phylum), increased Firmicutes (phylum), and Firmicutes/Bacteroidetes ratio (P_{(Interaction)} < 0.05). These results suggest that supplementing 25-OH-D₃ in diets may elevate gut health through the improvement of intestinal barrier function, antioxidant capacity and cecal microbiota composition in laying hens with high stocking density.

1,25-Dihydroxyvitamin D and S-Klotho Plasma Levels: The Relationship Between Two Renal Antiaging Biomarkers Mediated by Bone Mineral Density in Middle-Aged Sedentary Adults

The main active metabolite of vitamin D, the 1,25-dihydroxyvitamin D (1,25(OH)₂D), and the shed form of the α-Klotho gene (S-Klotho) play an important role in aging-related physiological processes and are currently considered powerful antiaging renal biomarkers. We aimed to investigate the relationship between 1,25(OH)₂D and S-Klotho plasma levels in middle-aged sedentary healthy adults. We also aimed to study the mediation role of body composition, physical activity levels, dietary parameters, and blood markers in the association between 1,25(OH)₂D and S-Klotho plasma levels. A total of 73 middle-aged sedentary adults (53.4% women; 53.7 ± 5.1 years old) were enrolled in this cross-sectional study. The 1,25(OH)₂D plasma levels were measured using a DiaSorin Liaison^® immunochemiluminometric analyzer. S-Klotho plasma levels were measured using a solid-phase sandwich enzyme-linked immunosorbent assay. Body composition analysis was performed using dual-energy X-ray absorptiometry scanner. A tendency toward a negative association was observed between 1,25(OH)₂D and S-Klotho plasma levels (β = -0.222, R² = 0.049, p = 0.059). The association was attenuated after controlling for age and sex and become significant after controlling for fat mass index. In addition, the association between 1,25(OH)₂D and S-Klotho levels was indirectly influenced by bone mineral density (BMD), with a percentage of mediation of 31.40%. Our study shows that 1,25(OH)₂D is negatively associated with S-Klotho plasma levels in middle-aged sedentary adults, which is partially mediated by BMD. Clinicaltrial.gov: ID: NCT03334357.

Vitamin D Deficiency Cause Gender Specific Alterations of Renal Arterial Function in a Rodent Model

Vitamin D deficiency shows positive correlation to cardiovascular risk, which might be influenced by gender specific features. Our goal was to examine the effect of Vitamin D supplementation and Vitamin D deficiency in male and female rats on an important hypertension target organ, the renal artery. Female and male Wistar rats were fed with Vitamin D reduced chow for eight weeks to induce hypovitaminosis. Another group of animals received normal chow with further supplementation to reach optimal serum vitamin levels. Isolated renal arteries of Vitamin D deficient female rats showed increased phenylephrine-induced contraction. In all experimental groups, both indomethacin and selective cyclooxygenase-2 inhibition (NS398) decreased the phenylephrine-induced contraction. Angiotensin II-induced contraction was pronounced in Vitamin D supplemented males. In both Vitamin D deficient groups, acetylcholine-induced relaxation was impaired. In the female Vitamin D supplemented group NS398, in males the indomethacin caused reduced acetylcholine-induced relaxation. Increased elastic fiber density was observed in Vitamin D deficient females. The intensity of eNOS immunostaining was decreased in Vitamin D deficient females. The density of AT₁R staining was the highest in the male Vitamin D deficient group. Although Vitamin D deficiency induced renal vascular dysfunction in both sexes, female rats developed more extensive impairment that was accompanied by enzymatic and structural changes.

Oxidative Stress and Low-Grade Inflammation in Polycystic Ovary Syndrome: Controversies and New Insights

The pathophysiology of Polycystic Ovary Syndrome (PCOS) is quite complex and different mechanisms could contribute to hyperandrogenism and anovulation, which are the main features of the syndrome. Obesity and insulin-resistance are claimed as the principal factors contributing to the clinical presentation; in normal weight PCOS either, increased visceral adipose tissue has been described. However, their role is still debated, as debated are the biochemical markers linked to obesity per se. Oxidative stress (OS) and low-grade inflammation (LGI) have recently been a matter of researcher attention; they can influence each other in a reciprocal vicious cycle. In this review, we summarize the main mechanism of radical generation and the link with LGI. Furthermore, we discuss papers in favor or against the role of obesity as the first pathogenetic factor, and show how OS itself, on the contrary, can induce obesity and insulin resistance; in particular, the role of GH-IGF-1 axis is highlighted. Finally, the possible consequences on vitamin D synthesis and activation on the immune system are briefly discussed. This review intends to underline the key role of oxidative stress and low-grade inflammation in the physiopathology of PCOS, they can cause or worsen obesity, insulin-resistance, vitamin D deficiency, and immune dyscrasia, suggesting an inverse interaction to what is usually considered.

Effects of a Single Oral Megadose of Vitamin D3 on Inflammation and Oxidative Stress Markers in Overweight and Obese Women: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

AIM

The study aimed to evaluate the effects of vitamin D3 (VD3) supplementation on inflammation and oxidative stress markers in overweight and obese women with deficiency or insufficiency of vitamin D.

METHODS

Twenty-nine overweight or obese women who had a deficiency or insufficiency of vitamin D were placed into two groups according to VD3 intervention. Patients in the supplemented group received a single oral megadose of VD3 (VD3, n=14). Patients in placebo group received a single oral identical capsule without vitamin D (placebo, n = 15). Anthropometric and biochemical variables were assessed at baseline and after 4-weeks intervention.

RESULTS

Anthropometric variables (waist circumference, waist-hip ratio, waist-height ratio and body mass index) were similar between groups (p > 0.05). VD3 supplementation increased the serum levels of 25-hydroxyvitamin D (p=0.000), malondialdehyde (p=0.021) and C-reactive protein (p=0.043) in overweight and obese women. Additionally, VD3 supplementation reduced the serum levels of aspartate aminotransferase (AST, p=0.035), alanine aminotransferase (ALT, p<0.0001) in overweight and obese women. Despite this, the serum levels of parathyroid hormone (PTH), fasting glucose (FG), and alpha-1- acid glycoprotein (A1GPA), total antioxidant capacity (TAC) were similar between groups.

CONCLUSION

In summary, a single oral megadose of VD3 increased 25-hydroxyvitamin D serum levels but did not improve oxidative stress and inflammation markers.

Calcitriol Supplementation Ameliorates Microvascular Endothelial Dysfunction in Vitamin D-Deficient Diabetic Rats by Upregulating the Vascular eNOS Protein Expression and Reducing Oxidative Stress

Diabetes mellitus contributes to macro- and microvascular complications, leading to adverse cardiovascular events. This study examined the effects of vitamin D deficiency on the vascular function and tissue oxidative status in the microcirculation of diabetic rats and to determine whether these effects can be reversed with calcitriol (active vitamin D metabolite) supplementation. Streptozotocin-induced diabetic rats were fed for 10 weeks with control diet (DC) or vitamin D-deficient diet without (DD) or with oral calcitriol supplementation (0.15 μg/kg) in the last four weeks (DDS) (10 rats each group). A nondiabetic rat group that received control diet was also included (NR). After 10 weeks, rats were sacrificed; mesenteric arterial rings with and without endothelium were studied using wire myograph. Western blotting of the mesenteric arterial tissue was performed to determine the protein expression of endothelial nitric oxide synthase (eNOS) enzyme. Antioxidant enzyme superoxide dismutase (SOD) activity and oxidative stress marker malondialdehyde (MDA) levels in the mesenteric arterial tissue were also measured. The DC group had significantly lower acetylcholine-induced relaxation and augmented endothelium-dependent contraction, with reduced eNOS expression, compared to NR rats. In mesenteric arteries of DD, acetylcholine-induced endothelium-dependent and sodium nitroprusside-induced endothelium-independent relaxations were lower than those in DC. Calcitriol supplementation in DDS restored endothelium-dependent relaxation. Mesenteric artery endothelium-dependent contraction of DD was greater than DC; it was not affected by calcitriol supplementation. The eNOS protein expression and SOD activity were significantly lower while MDA levels were greater in DD compared to DC; these effects were not observed in DDS that received calcitriol supplementation. In conclusion, vitamin D deficiency causes eNOS downregulation and oxidative stress, thereby impairing the vascular function and posing an additional risk for microvascular complications in diabetes. Calcitriol supplementation to diabetics with vitamin D deficiency could potentially be useful in the management of or as an adjunct to diabetes-related cardiovascular complications.

Flavonoid-rich fraction attenuates permethrin-induced toxicity by modulating ROS-mediated hepatic oxidative stress and mitochondrial dysfunction ex vivo and in vivo in rat

The present study explores the antioxidant, anti-microbial, and hepatoprotective potentials of flavonoid-rich fractions from Fumaria officinalis against permethrin-induced liver damage ex vivo/in vivo in rat. However, HPLC-DAD analysis revealed the richness of 6 components in ethyl acetate fraction (EAF) where ferulic acid, rosmarinic acid, and myricetin are the most abundant. The in vitro assays showed that EAFs have impressive antioxidant and anti-microbial properties. Ex vivo, permethrin (PER) (100 μM) induced a decrease of hepatic AST and ALT activities and 25-OH vitamin D and vitamin C levels and an increase of ALP and LDH activities, TBARS, and ϒ-GT levels with a disturbance of oxidative status. The hepatoprotective effect of EAF (1 mg/mL) against PER was confirmed by the amelioration of oxidative stress profile. In vivo, permethrin was found to increase absolute and relative liver weights, plasma transaminase activities, lactate-to-pyruvate ratio, hepatic and mitochondrial lipid peroxidation, and protein oxidation levels. This pesticide triggered a decrease of Ca²⁺ and Mg²⁺-ATPases and mitochondrial enzyme activities. The co-treatment with EAF reestablished the hepatic and mitochondrial function, which could be attributed to its richness in phenolic compounds.

The coronavirus disease (COVID-19) - A supportive approach with selected micronutrients

Worldwide the pandemic of COVID-19 spreads rapidly and has had an enormous public health impact with substantial morbidity and mortality especially in high-risk groups, such as older people and patients with comorbidities like diabetes, dementia or cancer. In the absence of a vaccine against COVID-19 there is an urgent need to find supportive therapies that can stabilize the immune system and can help to deal with the infection, especially for vulnerable groups such as the elderly. This is especially relevant for our geriatric institutions and nursing homes. A major potential contributing factor for elderly is due to their high incidence of malnutrition: up to 80% among the hospitalized elderly. Malnutrition results when adequate macronutrients and micronutrients are lacking in the diet. Often missing in public health discussions around preventing and treating COVID-19 patients are nutritional strategies to support optimal function of their immune system. This is surprising, given the importance that nutrients play a significant role for immune function. Several micronutrients, such as vitamin D, retinol, vitamin C, selenium and zinc are of special importance supporting both the adaptive and innate immune systems. As suboptimal status or deficiencies in these immune-relevant micronutrients impair immune function and reduces the resistance to infections, micronutrient deficiencies should therefore be corrected as soon as possible, especially in the elderly and other vulnerable groups. According to epidemiological, experimental and observational studies, some case reports and a few intervention studies the supplementation of vitamin D and/or zinc are promising. The multiple anti-inflammatory and immunomodulatory effects of Vitamin D could explain its protective role against immune hyper reaction and cytokine storm in patients with severe COVID-19. A randomized, placebo-controlled intervention study even shows that high dose vitamin D supplementation promotes viral clearance in asymptomatic and mildly symptomatic SARS-CoV-2 positive individuals. Besides, the data of a recent prospective study with COVID-19 patients reveal that a significant number of them were zinc deficient. The zinc deficient patients had more complications and the deficiency was associated with a prolonged hospital stay and increased mortality. Thus, immune-relevant micronutrients may help to increase the physiological resilience against COVID-19.

Micronutrient therapy and effective immune response: a promising approach for management of COVID-19

The escalating prevalence of coronavirus disease 2019 (COVID-19) worldwide, with an increased rate of morbidity and mortality, highlights an urgent need to develop more effective therapeutic interventions. Despite the authorized treatment against COVID-19 by the European Union (EU), the safety and effectiveness of this therapeutic strategy for a wide variety of patients have remained a significant challenge. In this respect, micronutrients such as vitamins and minerals, as essential factors, can be considered for improving the function of the immune system and accelerating the treatment procedure. Dietary supplements can attenuate vascular and inflammatory manifestations related to infectious diseases in large part due to their anti-inflammatory and antioxidant properties. Recently, it has been revealed that poor nutritional status may be one of the notable risk factors in severe COVID-19 infections. In the current review, we focus on the micronutrient therapy of COVID-19 patients and provide a comprehensive insight into the essential vitamins/minerals and their role in controlling the severity of the COVID-19 infection. We also discuss the recent advancements, challenges, negative and positive outcomes in relevance to this approach.

The relationship between vitamin D deficiency and oxidative stress can be independent of age and gender

Abstract. The active vitamin D (1,25(OH)2D) acts through a nuclear receptor to perform several functions in cellular metabolism. 1,25(OH)2D participates directly in calcium homeostasis, regulates the immune system, nervous system, blood pressure, insulin secretion, among others. Vitamin D deficiency could also be associated with several diseases and increased cellular oxidative damage. The present study aimed to investigate whether lipid peroxidation and/or protein oxidation are affected by vitamin D deficiency and whether sunlight exposure/diet, gender, and age might influence this relationship. Vitamin D concentrations were obtained from the Heart Hospital database and a questionnaire was applied among the 212 participants. We used the inactive vitamin D (25(OH)2) in the analyses since 1,25(OH)2D has a short half-life and a low blood concentration. Lipid peroxidation and protein oxidation analyses were performed using spectrophotometry. Multivariate analyses suggested the participation of vitamin D deficiency (<30 ng/mL) and sunlight/diet in oxidative stress (p <0.05; R2 MDA: 0.562; R2 CG: 0.429). Multiple linear regression test show that the age and gender of patients are not interfering in the analyses (p>0.05). Therefore, we suggest that the relationship between vitamin D deficiency and oxidative stress can be independent of age and gender.

Molecular mechanisms from insulin-mimetic effect of vitamin D: treatment alternative in Type 2 diabetes mellitus

Diabetes mellitus is a complex and multifactorial disease with a global prevalence that exceeds 425 million people. Type 2 diabetes mellitus (T2DM) is characterized by a state of insulin resistance, which leads to metabolic alterations that aggravate the state of health of people. Vitamin D deficiency appears to play an important role in the triggering mechanisms of insulin resistance. In this review, an analysis is made of the biochemical mechanisms associated with the insulin-mimetic effect of vitamin D, its supplementation being a possible nutritional strategy for the T2DM treatment. The current scientific evidence is extensive regarding the dose of vitamin D used for an insulin-mimetic effect. However, clinical trials and systematic reviews show statistical differences on glucose, insulin, and glycated hemoglobin levels of patients with T2DM, associated with activation mechanisms of transcription factors related to genes of the glucide metabolism and the insulin receptor, and the regulation of intracellular Ca2+ insulin concentrations. Likewise, an indirect mechanism associated with antioxidant and anti-inflammatory effects has been shown that also leads to sensitivity to the insulin receptor. The use of a specific dose of vitamin D could be an effective alternative in the T2DM treatment, which would reduce the risk of complications derived from hyperglycemia.

Serum 25-hydroxyvitamin D levels and psychological distress symptoms in patients with affective disorders during the COVID-19 pandemic

BACKGROUND

The COVID-19 pandemic has given rise to stress worldwide, especially in vulnerable people like those suffering from mental illness. This study aims to investigate the psychological distress perceived by a cohort of patients with Major Depressive Disorder (MDD) or Bipolar Disorder (BD) after a seven-week period of lockdown measures, and to analyze serum 25-hydroxyvitamin D [25(OH)D] levels as a potential predictor of distress severity.

METHODS

Fifty-nine remitted MDD and fifty-three euthymic BD patients were enrolled. An online dedicated survey was administered to obtain lockdown-related information and to evaluate COVID-19 related distress by using the Kessler 10 Psychological Distress Scale (K10). Patients' medical records were reviewed to collect sociodemographic and clinical data, including serum 25(OH)D levels dosed in the three months preceding the outbreak. A multivariate general linear model was adopted to test the effect of factors of interest on psychological distress.

RESULTS

In our sample (n = 112), 29 subjects (25.9 %) reported no likelihood of psychological distress, whereas 35 (31.2 %) and 48 (42.9 %) displayed mild and moderate-to-severe likelihood of psychological distress, respectively. Low serum 25(OH)D levels (p = 0.005) and MDD diagnosis (p = 0.001) specifically predicted the severity of psychological distress. Living alone during the lockdown, a longer duration of illness, and smoking habits were more frequently detected in subjects with COVID-19 related distress.

CONCLUSIONS

Low serum 25(OH)D levels and MDD diagnosis predicted an increased vulnerability to the stressful impact of the COVID-19 outbreak. Our results suggest that vitamin D may represent a biological factor mediating the psychological response to stress in individuals with affective disorders and provide further insight into tailoring intervention strategies.

Twelve-Week Daily Consumption of ad hoc Fortified Milk with ω-3, D, and Group B Vitamins Has a Positive Impact on Inflammaging Parameters: A Randomized Cross-Over Trial

Background and Aim: A state of chronic, subclinical inflammation known as inflammaging is present in elderly people and represents a risk factor for all age-related diseases. Dietary supplementation with ad hoc fortified foods seems an appealing strategy to counteract inflammaging. The purpose of this study was to test the efficacy of elderly-tailored fortified milk on inflammaging and different health parameters. Methods: A double-blind randomized cross-over study was performed on forty-eight volunteers aged 63–80 years. The fortified milk was enriched with ω-3 polyunsaturated fatty acids (eicosapentaenoic acid, EPA; docosahexaenoic acid, DHA), vitamins (25-hydroxyvitamin D, E, C, B6, B9, B12), and trace elements (zinc, selenium). The two intervention periods lasted for 12 weeks, with a 16-week washout intermission. Results: Compared to placebo, the consumption of fortified milk increased the circulating levels of different micronutrients, including vitamins and the ω-3 index of erythrocyte membranes. Conversely, it reduced the amount of arachidonic acid, homocysteine, and ω-6/ω-3 ratio. Conclusion: Twelve-week daily consumption of adhoc fortified milk has an overall positive impact on different health parameters related to inflammaging in the elderly.

Protective and curative role of vitamin D and hormones on the cadmium-induced inhibition of proliferation of human osteoblast cells

Objectives Exposure to cadmium (Cd), which causes environmental and industrial pollution, causes toxicity in many tissues and organs, especially bone, lung and kidney. Hormones, growth factors and other stimuli act on bone tissue through osteoblasts. In this study, it was aimed to determine the effects of Cd on hFOB1.19 osteoblast cells and the protective and healing potentials of estrogen, androgen and vitamin D against the inhibitory effect of Cd on the proliferation. Methods hFOB1.19 cells were cultivated in our laboratory using Dulbecco's Modified Eagle's Medium-F12, HEPES medium, containing 10% fetal bovine serum, 1% penicillin/streptomycin in 34.5 °C 5%CO2 incubator. To determine its protective potentials for the toxicity of CdCl2, it was previously applied 1,25(OH) 2D vitamin, 17β-estradiol, and 5α-androstane for 72 h to cells. To determine their curative potential, osteoblast cells, which were previously exposed to CdCl2 for 72 h, were administered 1,25(OH) 2D vitamin, 17β-estradiol, and 5α-androstane. Following these applications were determined proliferation by XTT analysis and, the amounts of androgen receptor, estrogen receptor, vitamin D receptor, alkaline phosphatase, osteocalcin and osteoprotegerin by ELISA analysis. Results Vitamin D has been both preventive and curative effective to increase cell proliferation, which Cd reduces. Interestingly, estrogen had a preventive effect and androgen had a curative effect. Conclusions In addition to showing the negative effects of cadmium on the proliferation of osteoblast cells, this study provides an overview of the effects of hormone and vitamin D applications before and after Cd, and these results may serve as a guide for future studies.

Vitamin D oral gel for prevention of radiation-induced oral mucositis: A randomized clinical trial

OBJECTIVES

The aim of this clinical trial is to evaluate the effectiveness of topical oral vitamin D gel in prevention of radiation-induced oral mucositis.

MATERIAL AND METHODS

A three-armed randomized controlled clinical trial on forty-five head and neck cancer patients was conducted. First group: conventional treatment. Second group: Topical oral vitamin D gel. Third group: topical oral vitamin D gel plus the conventional treatment. All the patients were examined clinically three and six weeks after the start of radiotherapy for pain and WHO mucositis score.

RESULTS

After 6 weeks of radiotherapy, (33.5%) the patients in control group developed high-grade severity of oral mucositis while the patients in the two-test groups "vitamin D group and combined therapy group" remained with low-grade severity or with complete remission. Mean pain scores showed a significant decrease in the combined therapy group and to a close degree in vitamin D group rather than the control group.

CONCLUSION

Topical oral vitamin D gel has a beneficial effect in lowering oral mucositis development and in reducing pain sensation during the radiation period especially when combined with conventional therapeutic agents.

Vitamin D Deficiency Induces Elevated Oxidative and Biomechanical Damage in Coronary Arterioles in Male Rats

Background: Several reports prove interconnection between vitamin D (VD) deficiency and increased cardiovascular risk. Our aim was to investigate the effects of VD status on biomechanical and oxidative–nitrative (O–N) stress parameters of coronary arterioles in rats. Methods: 4-week-old male Wistar rats were divided into a control group (11 animals) with optimal VD supply (300 IU/kgbw/day) and a VD-deficient group (11 animals, <5 IU/kg/day). After 8 weeks, coronary arteriole segments were prepared. Geometrical, elastic, and biomechanical characteristics were measured by in vitro arteriography. O–N stress markers were investigated by immunohistochemistry. Results: Inner radius decreased; wall thickness and wall-thickness/lumen diameter ratio increased; tangential wall stress and elastic modulus were reduced in VD-deficient group. No difference could be found in wall-cross-sectional area, intima-media area %. While the elastic elements of the vessel wall decreased, the α-smooth muscle actin (α-SMA) immunostaining intensity showed no changes. Significant elevation was found in the lipid peroxidation marker of 4-hidroxy-2-nonenal (HNE), while other O–N stress markers staining intensity (poly(ADP)ribose, 3-nitrotyrosine) did not change. Conclusions: Inward eutrophic remodeling has developed. The potential background of these impairments may involve the initial change in oxidative damage markers (HNE). These mechanisms can contribute to the increased incidence of the cardiovascular diseases in VD deficiency.

Evaluation of the efficacy of two doses of vitamin D supplementation on glycemic, lipidemic and oxidative stress biomarkers during pregnancy: a randomized clinical trial

BACKGROUND

Vitamin D deficiency during pregnancy is common and is likely to be associated with metabolic complications in the mother. The aim of this study was to assess the efficacy of two doses of vitamin D supplementation during pregnancy on maternal and cord blood vitamin D status and metabolic and oxidative stress biomarkers.

METHODS

The eligible pregnant women (n = 84) invited to participate in the study and randomly allocated to one of the two supplementation groups (1000 IU/d vitamin D and 2000 IU/d). Biochemical assessments of mothers including serum concentrations of 25(OH)D, calcium, phosphate, iPTH, fasting serum sugar (FBS), insulin, triglyceride, total cholesterol, LDL-C, HDL-C, malondialdehyde (MDA) and total antioxidant capacity (TAC) were done at the beginning and 34 weeks of gestation. Cord blood serum concentrations of 25(OH)D, iPTH, MDA and TAC were assessed at delivery as well. To determine the effects of vitamin D supplementation on metabolic markers 1-factor repeated-measures analysis of variance (ANOVA) was used. Between groups comparisons was done by using Independent-samples Student's t-test or Mann-Whitney test. P < 0.05 was considered as significant.

RESULTS

Supplementation with 1000 IU/d and 2000 IU/d vitamin D resulted in significant changes in vitamin D status over pregnancy (24.01 ± 21.7, P < 0.001 in 1000 IU/d group and 46.7 ± 30.6 nmol/L, P < 0.001 in 2000 IU/d group). Daily intake of 2000 compared with 1000 IU/d tended to increase the serum concentration of HDL-C (10 ± 8.37, P < 0.001 in 1000 IU/d group and 9.52 ± 11.39 mg/dL, P < 0.001 in 2000 IU/d group). A significant decrement in serum concentration of iPTH observed in both groups (- 4.18 ± 7.5, P = 0.002 in 1000 IU/d group and - 8.36 ± 14.17, P = 0.002 in 2000 IU/d group).

CONCLUSIONS

Supplementation with 2000 IU/d vitamin D as compared with 1000 IU/d, is more effective in promoting vitamin D status and HDL-C serum concentration and in decreasing iPTH over pregnancy.

TRIAL REGISTRATION

This trial is registered at clinicaltrials.gov ( NCT03308487 ). Registered 12 October 2017 'retrospectively registered'.

Beneficial relevance of vitamin D concentration and urine flow rate

BACKGROUND & AIMS

Micturition dysfunction is a problem in the general population that progresses with aging in both males and females. In the past few decades, the relationship between voiding symptoms and body biochemical status has been a subject of research in several disciplines. Micronutrition is considered to affect different aspects of urinary flow, including neuroregulation, detrusor muscle function, and the structures around the bladder outlet such as the pelvic floor and prostate. Therefore, the objective of our study was to determine the correlation between urine flow rate (UFR) and 25-hydroxyvitamin D (25(OH)D) in the general healthy population.

METHODS

Our study involved 3981 adult participants over age 20 from the U.S. National Health and Nutrition Examination Survey datasets (2011-2012). The associations between UFR and serum 25(OH)D concentration were analyzed through multivariate regression models.

RESULTS

There was a significant positive association of serum 25(OH)D concentration with UFR (25(OH)D₂+25(OH)D₃: β coefficient: 0.003; 95% CI: 0.002, 0.004; p < 0.001, 25(OH)D₃; p = 0.003; epi-25(OH)D₃, p = 0.020) in an unadjusted model. The substantial associations were still observed in the gender and age subgroups. In analysis of age subgroup, the association of serum 25(OH)D concentration with urine flow rate was significant in fully adjusted model (age<60: 25(OH)D₂+25(OH)D₃: β coefficient: 0.004, p < 0.001; 25(OH)D₃: p = <0.001, epi-25(OH)D₃: p = 0.007; Age≥60: 25(OH)D₂+25(OH)D₃: β coefficient: 0.004, p = 0.002; 25(OH)D₃: p = 0.001, epi-25(OH)D₃: p = 0.001). In gender subgroup analysis, the β coefficient of 25(OH)D₂+25(OH)D₃ in male is 0.004 (p < 0.001), and in female is 0.004 (p < 0.001) in fully adjusted model. The higher quartiles of UFR tended to have higher 25(OH)D₃ levels with statistically significant in quartile-based analysis.

CONCLUSIONS

UFR was associated with increased level of total vitamin D and bioactive form vitamin D₃. Vitamin D supplements may be a simple and effective way of improving of bladder function.

Immune-Boosting, Antioxidant and Anti-inflammatory Food Supplements Targeting Pathogenesis of COVID-19

The COVID-19 is an acute and contagious disease characterized by pneumonia and ARDS. The disease is caused by SARS-CoV-2, which belongs to the family of Coronaviridae along with MERS-CoV and SARS-CoV-1. The virus has the positive-sense RNA as its genome encoding for ~26 proteins that work together for the virus survival, replication, and spread in the host. The virus gets transmitted through the contact of aerosol droplets from infected persons. The pathogenesis of COVID-19 is highly complex and involves suppression of host antiviral and innate immune response, induction of oxidative stress followed by hyper inflammation described as the "cytokine storm," causing the acute lung injury, tissue fibrosis, and pneumonia. Currently, several vaccines and drugs are being evaluated for their efficacy, safety, and for determination of doses for COVID-19 and this requires considerable time for their validation. Therefore, exploring the repurposing of natural compounds may provide alternatives against COVID-19. Several nutraceuticals have a proven ability of immune-boosting, antiviral, antioxidant, anti-inflammatory effects. These include Zn, vitamin D, vitamin C, curcumin, cinnamaldehyde, probiotics, selenium, lactoferrin, quercetin, etc. Grouping some of these phytonutrients in the right combination in the form of a food supplement may help to boost the immune system, prevent virus spread, preclude the disease progression to severe stage, and further suppress the hyper inflammation providing both prophylactic and therapeutic support against COVID-19.