Vitamina D: ações extraósseas e uso racional

Mini-Review: Electrochemical Sensors Used for the Determination of Water- and Fat-Soluble Vitamins: B, D, K

Vitamins are one of the most essential organic compounds that are necessary for the human body, in order to develop and grow in a healthy way. The aim of this mini-review is to bring together a series of electrochemical sensors (voltametric and amperometric) developed for the determination of vitamins from the families of B, D and K in biological, pharmaceutical or food-related samples. For this mini-review, 16 articles published between 2016 and 2021 were taken into consideration.

Use of vitamins and/or minerals among adults and the elderly in urban areas of Brazil: prevalence and associated factors

The purpose of the present study was to estimate the prevalence of vitamin and/or mineral use among urban Brazilian populations aged 20 years and over and to identify associated factors. Data from the National Survey on Access, Use and Promotion of the Rational Use of Medicines in Brazil (PNAUM) were analyzed and a population-based cross-sectional study with probability sampling was performed in urban areas of Brazil's five geographic regions from September 2013 to February 2014. The estimated prevalence of vitamin and/or mineral use was 4.8% (95%CI: 4.3-5.3), higher in women 6.4% (95%CI: 5.7-7.1) and in the elderly population 11.6% (95%CI: 10.5-12.8). Vitamin and/or mineral use was associated with the following factors: women, 60 years of age or older, economic class A/B, chronic disease(s) and self-perceived health held as average and very poor/poor. Multivitamins and multiminerals were the most used ones with 24.5% (95%CI 20.1-29.4), followed by calcium and vitamin D with 23.4% (95%CI 19.7-27.5). Data suggest that elderly women should be the reference public for actions aimed at promoting rational use. Nationwide epidemiological surveys should increase monitoring of these products to support the analysis of trends.

Advancement in the Treatment of Osteoporosis and the Effects on Bone Healing

Osteoporosis (OP) is a major global health concern, with aging being one of the most important risk factors. Osteoarthritis (OA) is also an age-related disorder. Patients with OP and/or OA may be treated surgically for fractures or when their quality of life is impaired. Poor bone quality due to OP can seriously complicate the stability of a bone fixation construct and/or surgical fracture treatment. This review summarizes the current knowledge on the pathophysiology of normal and osteoporotic bone healing, the effect of a bone fracture on bone turnover markers, the diagnosis of a low bone mineral density (BMD) before surgical intervention, and the effect of available anti-osteoporosis treatment. Interventions that improve bone health may enhance the probability of favorable surgical outcomes. Fracture healing and the treatment of atypical femoral fractures are also discussed.

Vitamin D attenuates COVID-19 complications via modulation of proinflammatory cytokines, antiviral proteins, and autophagy

INTRODUCTION

Global emergence of coronavirus disease-19 (COVID-19) has clearly shown variable severity, mortality, and frequency between and within populations worldwide. These striking differences have made many biological variables attractive for future investigations. One of these variables, vitamin D, has been implicated in COVID-19 with rapidly growing scientific evidence.

AREAS COVERED

The review intended to systematically explore the sources, and immunomodulatory role of vitamin D in COVID-19. Search engines and data sources including Google Scholar, PubMed, NCBI, Scopus, and Web of Science were used for data collection. The search terms used were Vitamin D, COVID-19, immune system, and antiviral mechanism. Overall, 232 sources of information were collected and 188 were included in this review.

EXPERT OPINION

Interaction of vitamin D and vitamin D receptor (VDR) triggers the cellular events to modulate the immune system by regulation of many genes. Vitamin D operates as a double-edged sword against COVID-19. First, in macrophages, it promotes the production of antimicrobial and antiviral proteins like β-defensin 2 and cathelicidin, and these proteins inhibit the replication of viral particles and promote the clearance of virus from the cells by autophagy. Second, it suppresses cytokine storm and inflammatory processes in COVID-19.

Association between vitamin D and cardioprotection in adult patients

OBJECTIVE

To conduct a review of articles which have evaluated the relationship between vitamin D and cardioprotection in adult.

METHODS

A literature search was performed in the Pubmed and Scielo databases. The results were extracted from primary and secondary sources and will be presented in the form of a bibliographic review.

RESULTS

Twenty-three articles were identified from the electronic search that reported on physiological mechanisms relating the vitamin D axis and the cardiovascular system through receptors. Of the ten studies that evaluated the therapeutic effect of vitamin D in cardiovascular diseases, none reported significant results.

CONCLUSION

The articles assessed in this review did not demonstrate a cardioprotective effect of vitamin D, despite the epidemiological correlation of vitamin D deficiency with a higher prevalence of cardiovascular diseases.

Effects of vitamin D supplementation on the glycemic control of pre-diabetic individuals: a systematic review

Introduction

Introduction: research shows the potential effect of vitamin D supplementation with an improvement in the glycemic profile of pre-diabetic patients. Objective: this study evaluates the effects of vitamin D supplementation on glycemic control markers in pre-diabetic individuals. Methods: we analyzed studies published over the last ten years, and indexed in the Science Direct, PubMed, and LILACS databases. We searched studies using health descriptors related to vitamin D, pre-diabetes, and glycemic control markers. We considered randomized controlled trials eligible for inclusion. All phases of selection, data extraction, and risk of bias assessment were carried out by two independent evaluators. Results: we identified 309 articles, of which 4 met the inclusion criteria. Of these, 3 studies have shown that vitamin D supplementation does not alter glycemic control markers in pre-diabetic individuals. Only one study showed a positive effect after supplementation with 60,000 IU/month of vitamin D3 for 12 months, with a significant reduction in the concentrations of glycated hemoglobin, fasting glucose, and two-hour postprandial glucose. Conclusion: there is insufficient scientific evidence to confirm the beneficial effects of vitamin D supplementation on glycemic control markers in pre-diabetic individuals.

Association of vitamin D and vitamin B12 with cognitive impairment in elderly aged 80 years or older: a cross-sectional study

BACKGROUND

The present study aimed to assess the association of vitamin D and vitamin B₁₂ with cognitive impairment in elderly people.

METHODS

The data were obtained from a cross-sectional study that included individuals aged 80 years or older living in the urban and rural areas of the cities of Siderópolis and Treviso in the state of Santa Catarina, Brazil. In total, 165 elderly people were included in the analysis. The outcome of cognitive decline was assessed by the Mini-Mental State Examination. Vitamin D and vitamin B₁₂ levels were measured from blood samples. The socio-demographic, anthropometric and health variables used in the analysis were collected from a questionnaire. Crude and adjusted analyses of the relationship between vitamins D and B₁₂ and cognitive decline were performed using a Poisson regression model.

RESULTS

The prevalence of cognitive decline was 35.2%. In the adjusted model, individuals who had vitamin D levels >19 ng mL^-1 showed a lower prevalence of cognitive decline (prevalence ratio = 0.59; 95% confidence interval = 0.39-0.87). Those participants who had vitamin B₁₂ levels of ≥496 pg mL^-1 had a higher prevalence of cognitive decline (prevalence ratio = 1.90; 95% confidence interval = 1.08-3.36).

CONCLUSIONS

The present study showed that individuals aged ≥80 years who had vitamin D levels of ≤18 ng mL^-1 had a higher prevalence of cognitive decline even after adjustment for potential confounders. In addition, the study demonstrated that vitamin B₁₂ levels of ≥496 pg mL^-1 in this population were also a risk factor for cognitive decline. A cross-sectional analysis does not enable the inference of a cause-effect relationship and additional studies are needed to understand these relationships.

Higher serum levels of vitamin D are associated with lower blood glucose levels

OBJECTIVE

Vitamin D plays an important role in bone metabolism. There is now evidence that a higher serum level of 25-hydroxyvitamin D (25[OH]D) is associated with a lower risk of developing type 2 diabetes mellitus, because it provides better glycemic control, possibly by promoting greater insulin sensitivity, and also by improving pancreatic beta cell function. The objective of the present study was to evaluate the possible association between 25(OH)D sufficiency and glycemia.

METHODS

This was a cross-sectional study involving 680 women, 35 to 74 years of age, selected through systematic sampling. From each participant, fasting blood samples were collected for the determination of 25(OH)D and glucose levels.

RESULTS

The mean fasting blood glucose level was 105 mg/dL (range 26-401 mg/dL). Fasting serum levels of 25(OH)D were <30 ng/mL in 65.4% of the participants and <20 ng/mL in 25.6%. A serum 25(OH)D level <30 ng/mL was positively associated with a blood glucose level ≥100 mg/dL (odds ratio [OR] 1.29, 95% confidence interval [CI] 1.05-1.57), as was a serum 25(OH)D level <20 ng/mL (OR 1.25, 95% CI 1.04-1.50).

CONCLUSIONS

Lower serum 25(OH)D concentrations appear to be associated with a high blood glucose levels.

Association of hematology profile with serum 25-hydroxy vitamin D and Bsml polimorphism in community-dwelling older adults

ABSTRACT Objective: To investigate the association between serum level of 25-hydroxy vitamin D and the Vitamin D Receptos gene BsmI polymorphism in the blood profile of community-dwelling older adults. Methods: This cross-sectional study included 142 older males and females. A questionnaire collected socio demographic information, medical history, and factors associated with sun exposure. Weight, height, and waist circumference were measured. Biological material was collected to analyze biochemical parameters 25-hydroxy vitamin D, parathormone, serum calcium, urea, creatinine, liver enzymes, and blood profile) and to verify the presence of the vitamin D receptos gene BsmI polymorphism. Results: Most participants were female (80.3%). The mean levels of 25-hydroxy vitamin D, hemoglobin, and hematocrit were 32.1±7.3 ng/dL, 13.5±1.5 d/dL, and 40.0±4.4%, respectively. Fifty-eight (40.8%) participants had vitamin D insufficiency/deficiency (25.7±3.3 ng/mL), and 18 (12.6%) had anemia. Serum vitamin D was associated with hemoglobin (p=0.030) and hematocrit (p=0.032). However, when subjects were categorized as anemic or not anemic, said association was not maintained (p=0.270). Moreover, the BsmI polymorphism was not associated with hemoglobin and hematocrit levels, regardless of vitamin D status. Conclusion: The serum level of vitamin D is associated with hematocrit and hemoglobin levels in older adults. However, these blood parameters were not associated with the vitamin D receptor gene BsmI polymorphism.