Variation In Vitamin Research Articles

Variation of vitamin C content and antioxidant capacities during the post-harvest storage of fresh fruits under different temperatures

During post-harvest storage, vitamins and health promoting compounds of fresh fruits are prone to change. Variation in ascorbic acid (ASC), total vitamin C (VitC), total phenolic (TPC) and total flavonoid (TFC) and antioxidant capacities (ACs) were studied during storage of fresh fruits (31 species) for 14 days at three different temperatures. During storage, ASC (1.6–90.0%) and VitC (0.1–71.6%) contents decreased significantly in most of the fruits, irrespective to the storage temperature. Interestingly accumulation of ASC (1.0–245.0%) and VitC (0.5–102.8%) was also observed in some fruit species; Musa paradisiaca, Aegal marmelos, Citrus aurantifolia and Passiflora edulis. All the fruits with the highest rate of accumulation of ASC and VitC are climacteric fruits; Musa paradisiaca, Persea americana etc. In Psidium guajava, almost all the measured health promoting compounds were significantly lost during storage. In most of the under-utilized fruits, significant loss in TPC (Artocarpus heterophyllus (‘Wela’) at room temperature: 87.4%), TFC (Averrhoa carambola: 100.0%) and ACs could be observed. The highest percentage of losses (100.0%) in DPPH radical scavenging assay and Ferric reducing antioxidant potential were observed in Citrullus lantanus. According to the results of multivariate analysis of variance (MANOVA), there is a statistically significant effect (p < 0.0005) of fruit species, storage temperature and an interaction effect of those on changing rates of measured antioxidants. The reduction rates of measured antioxidants are significantly highest at room temperature, while which are significantly highest under freezing conditions compared to refrigeration. Refrigeration temperature is recommended for optimization of preservation of vitamin C and antioxidants during storage of fresh fruits.

Metabolic and hormonal profiling in polycystic ovarian syndrome: insights into INSR gene variations.

Polycystic Ovary Syndrome (PCOS) is a hormonal disorder characterized by irregular periods, excess androgen levels, and polycystic ovaries, affecting many women of reproductive age. This study employed statistical and molecular analyses to compare hormone and metabolic markers between PCOS patients and controls. Sanger sequencing identified two INSR gene variants linked to high insulin and pre-diabetic conditions. Statistically, no significant age differences were detected (p = 0.492) between the overall PCOS patient pool and controls. However, a substantial variation in Vitamin D levels was observed within PCOS patients compared to controls (p = 0.0006), suggesting an association with PCOS. Correlations between Vitamin D and insulin, as well as HbA1c levels (R2 = 0.141 and 0.143, respectively), suggest Vitamin D's potential impact on glycemic control. Significant differences were found in HbA1c (p < 0.0001), insulin (p < 0.0001), and LDL (p = 0.0004) levels between PCOS patients and controls, highlighting marked disparities in these metabolic markers. LH levels also showed a significant contrast (p < 0.0001), while progesterone levels displayed a notable difference (p = 0.007) between the two groups. Correlation analyses within PCOS patients demonstrated associations among LDL, HbA1c, and insulin, with no such correlations observed in control cases. Additionally, Sanger sequencing identified two INSR gene variants, c.3614C > T (p.Pro1205Leu) and c.3355C > T (p.Arg1119Trp), associated with high insulin, LH, and pre-diabetic conditions. These amino acid changes may trigger metabolic imbalances and hormonal irregularities, potentially contributing to the development of PCOS. The findings highlight the multifaceted nature of PCOS, revealing significant metabolic, hormonal, and genetic differences compared to controls. These insights may inform tailored interventions and management strategies for the complex associations characteristic of PCOS.

Effects of Replacing Cow's Milk with Plant-Based Beverages on Potential Nutrient Intake in Sustainable Healthy Dietary Patterns: A Case Study.

More consumers are replacing cow's milk (CM) with plant-based drinks (PBD), but data indicating the nutritional impact are limited. This theoretical study aims to assess the effect of substituting CM with PBD sold in Italy on nutrient intake within two dietary patterns: one aligned with the EAT-Lancet Commission reference diet adapted to Italian food habits (EAT-IT) and another one in line with the Italian Dietary Guidelines (IDG). Nutrition information from 368 PBD were collected and categorized according to their descriptive name and their fortification or not with calcium (Ca- and nCa-fortified). The substitution of CM with each PBD category in both dietary patterns was conducted, and an analysis of nutrient content and adequacy was performed. Substituting CM with all PBD resulted in reduced protein intake, except for nCa-fortified soy drinks, decreased saturated fat and vitamins B2 and B12, and increased fiber intake. Replacing CM with nCa-fortified PBD within both diets decreased Ca intake. Following the substitution of CM with Ca-fortified PBD, variations in vitamin D intake depended on the PBD category. The main risk of nutritional inadequacy was observed in Ca and vitamin D levels, which may even be amplified considering the different bioavailability based on the source of nutrients. This study highlighted the important role of CM in meeting calcium requirements and the potential unintended consequences of substituting CM with PBD without considering their nutritional differences.

Unlocking the genetic basis of vitamin E content in sweet corn kernels: Expanding breeding targets through genome-wide association studies

Tocochromanols, collectively known as Vitamin E, serve as natural lipid-soluble antioxidants that are exclusively obtained through dietary intake in humans. Synthesized by all plants, tocochromanols play an important role in protecting polyunsaturated fatty acids in plant seeds from lipid peroxidation. While the genes involved in tocochromanol biosynthesis have been fully elucidated in Arabidopsis thaliana, Oryza sativa and Zea mays, the genetic basis of tocochromanol accumulation in sweet corn remains poorly understood. This gap is a consequence of limited natural genetic diversity and harvest at immature growth stages. In this study, we conducted comprehensive genome-wide association studies (GWAS) on a sweet corn panel of 295 individuals with a high-density molecular marker set. In total, thirteen quantitative trait loci (QTLs) for individual and derived tocochromanol traits were identified. Our analysis identified novel roles for three genes, ZmCS2, Zmshki1 and ZmB4FMV1, in the regulation of α-tocopherol accumulation in sweet corn kernels. We genetically validated the role of Zmshki1 through the generation of a knock-out line using CRISPR-Cas9 technology. Further gene-based GWAS revealed the function of the canonical tyrosine metabolic enzymes ZmCS2 and Zmhppd1 in the regulation of total tocochromanol content. This comprehensive assessment of the genetic basis for variation in vitamin E content establishes a solid foundation for enhancing vitamin E content not only in sweet corn, but also in other cereal crops.

Clinical Signs and Laboratory Tests for the Differential Diagnosis ofAndrogenic and Post-COVID-19 Alopecia in Women

Background: Pathological hair loss in women has emerged as a prevalent cause for seeking specialized dermatological and cosmetic services. The most common type of this condition is androgenetic alopecia, which arises due to hormonal and micronutrient imbalances.Furthermore, during the COVID-19 epidemic, there has been a notable increase in the number of female patients with pathological hair loss as a complication of the disease, with some individualsexperiencing alopecia the sole indication of asymptomatic COVID-19. Aims: The aim of the study wassearch for objective criteria for the differential diagnosis of androgenetic alopecia and post-COVID alopecia in women based on informative trichological and laboratory markers. Materials and methods: The including criteria for androgenetic alopecia (AGA) group were elevated dihydrotestosterone (DHT) levels, clinical indications of alopecia corresponding to initial stages of the condition, and a past experience of continuous observation untilFebruary 2020. For the post-COVID alopecia (COVID) group, inclusion criteria were a confirmed diagnosis of COVID-19 using RT-PCR and the presence of alopecia symptoms emerging within a year post-infection. Evaluation of quantitative characteristics of hairs was conducted was carried out based on trichogram and phototrichogram data, followed by image processing using a computer diagnostic program. Key indicators for hair growth were identified in patients' plasma, including DHT, vitamins B9 (folic acid), B12, D (25(OH)-D3 form), E, as well as calcium (Ca), iron (Fe), magnesium (Mg), selenium (Se), copper (Cu), and zinc (Zn). CART algorithm (Classification and Regression Trees) based on recursive partitioning of available data with selection of informative predictors and formation of a tree-like hierarchical structurewas applied to determine criteria to differentiate between patients with androgenetic and post-COVID alopecia. Results: Analysis of trichograms and phototrichograms revealed that unlike androgenetic alopecia, which primarily impacts hair follicles in the telogen and anagen phases in the androgen-dependent zone, post-COVID hair loss presents as a diffuse telogen effluvium pattern, involving the androgen-dependent (parietal) area of the scalp. Notably, patients with post-COVID alopecia exhibited elevated dihydrotestosterone levels compared to reference values, with no significant differencein comparison to AGA. While there were no variations in vitamin and certain trace element levels (Fe, Ca, Mg, Zn), individuals in COVID group have demonstrated a statistically significant reduction in copper content (46.4% lower than AGA; p=0.006) alongside an increase in selenium levels (24.7% higher than AGA; p=0.003). Conclusions: The performed study for the first time presents objective criteria for the differential diagnosis of androgenetic and post-COVID alopecia in women. The data obtained show a diffuse pattern of telogen effluvium after recovering from COVID-19, linked to an imbalance in trace elements - specifically, a decrease in copper (Cu) and an increase in selenium (Se). Based on this fact, the algorithm CART used allows for a highly effective differentiation of the compared variants of pathological hair loss in studied patients and forms the basis for pathogenetically justified conservative therapy.

Characterizing and decoding the key odor-active compounds in fresh, pasteurized, and high pressure processing sea buckthorn (Hippophae rhamnoides L.) juice

The non-thermal and thermal effects on aroma of sea buckthorn juice have rarely been investigated. In this study, 57 odor compounds were identified in fresh sea buckthorn juice (FSBJ), high pressure processing sea buckthorn juice (HSBJ), and pasteurized sea buckthorn juice (PSBJ), including 29 esters, 8 aldehydes, 1 ketone, 5 alcohols, 5 acids, 6 terpenoids, and 3 others. Ethyl 2-methylbutanoate, ethyl 3-methylbutanoate, ethyl hexanoate, and ethyl 2-hydroxy-3-methylbutanoate with flavor dilution factors ranging from 729 to 59,049 contributed to the fruity odors of FSBJ and HSBJ. Besides, the formation of off-odor compounds including hexanal, nonanal, furfural, 3-methylbutanoic acid, and dimethyl disulfide with odor activity values ≥ 1, imparts fatty, roasted, sweaty, and cooked odor in PSBJ. The variations of vitamin C and reducing sugar are significantly associated with changes in odor-active compounds during pasteurized processing. These findings provide new insights that high pressure processing minimizes the adverse effects of pasteurization.

Vitamin D Deficiency in Professional Football Players during Competitive Season of Italian First Division (Serie A).

Data in the literature have demonstrated the crucial role that vitamin D plays in the human organism, and recent studies also emphasize this essential role of vitamin D in athletes. Indeed, vitamin D acts on the skeletal muscles and plays a fundamental role in numerous physiological processes involved in immune function. Many factors such as sun exposure, skin tone, body mass index and chronic illness affect vitamin D levels. The aim of the study is to evaluate vitamin D levels in professional football players in Italy and investigate the variations in vitamin D values in footballers who train at different latitudes. The study performed is a retrospective observational study analyzing 25-OH vitamin D values in professional football players of the Italian First Division (Serie A). Two teams during the competitive season were selected: team A (latitude of 41° N in southern Italy) and team B (latitude of 45° N in northern Italy). Three time periods were identified and were classified as follows: the first quarter (May, June, July, and August), the second quarter (September, October, November, and December) and the third quarter (January, February, March, and April). The purpose of this was to study the average values of vitamin D during the year corresponding to different levels of sunlight exposure. Each athlete was subjected to at least one sampling during the three quarters of the competitive season. Both vitamin D insufficiency (10.1%) and overt deficiency (1.93%) were found in Italian Serie A players. Insufficient vitamin D values are between 20 ng/mL and 29 ng/mL and overt deficiency values <20 ng/mL. At the same time, the data demonstrated a significant variation in vitamin D values depending on the period of the competitive season and the latitude of the cities of the two teams. In detail, there was no significant difference in the first quarter, while there was a significant increase in vitamin D values in team B in the second and third quarter, at p < 0.01 and p < 0.05, respectively. Latitude and seasons have a significant impact on vitamin D levels. Therefore, it is essential to measure vitamin D in professional football players, especially during the spring and winter months, so as to monitor changes in levels in relation to the season and latitude and evaluate any supplements. Further studies should be performed to evaluate the relationship between vitamin D deficiency and football players' athletic performance.

The Influence of Organic Manures on Proximate Composition, Minerals, Anti-nutrients and Vitamins of Selected Legume Forage

This study investigated the influence of three organic manure on the nutritional composition of three leguminous forages - Soybeans, Cowpeas, and Groundnuts, cultivated in the coastal Rainforest of Akwa Ibom State, Nigeria. The four different organic manure used were poultry droppings, goat droppings, pig dung and a control (no manure application). Each organic manure represented a treatment group. Each group was replicated three times making a total of 12 experimental units. The data collected were subjected to analysis of variance using the Statistical Package for Social Science (SPSS). Proximate analysis revealed significant (p&lt;0.05) differences in moisture, fat, ash, protein, fiber, carbohydrates, and energy content. Manure type significantly (p&lt;0.05) affected protein, carbohydrate, and moisture content. Poultry Manure had superior performance in Cowpea Forage, while Control excelled in Soybean Forage. The anti-nutrient analysis revealed significant (p&lt;0.05) differences in tannin, oxalate, saponin, and phytate content, impacting nutritional quality. Tannin content varied significantly (Groundnut: 65.78 mg/100g, Soybean: 109.78 mg/100g, Cowpea: 37.62 mg/100g), as did oxalate (Groundnut: 393.18 mg/100g, Soybean: 185.20 mg/100g, Cowpea: 357.13 mg/100g), saponin (Groundnut: 5.71 mg/100g, Soybean: 6.63 mg/100g, Cowpea: 6.63 mg/100g), and phytate (Groundnut: 160.89 mg/100g, Soybean: 30.63 mg/100g, Cowpea: 21.22 mg/100g). Vitamin analysis revealed variations in vitamin C (Groundnut: 57.94 mg/100g, Soybean: 58.31 mg/100g, Cowpea: 63.17 mg/100g) and β-carotene (Groundnut: 9.73 mg/100g, Soybean: 9.46 mg/100g, Cowpea: 7.51 mg/100g), indicating nutritional attributes of the studied leguminous forages. Based on the results, the treatment involving poultry dropping, goat dropping, pig dung and control all demonstrated good performance in terms of contributing to the nutritional composition of cowpea, groundnut and soybean. Thus, the use of poultry dropping and pig dung as organic manure for farmers in the region could be recommended.

The Influence of Organic Manures on Proximate Composition, Minerals, Anti-nutrients and Vitamins of Selected Legume Forage

This study investigated the influence of three organic manure on the nutritional composition of three leguminous forages - Soybeans, Cowpeas, and Groundnuts, cultivated in the coastal Rainforest of Akwa Ibom State, Nigeria. The four different organic manure used were poultry droppings, goat droppings, pig dung and a control (no manure application). Each organic manure represented a treatment group. Each group was replicated three times making a total of 12 experimental units. The data collected were subjected to analysis of variance using the Statistical Package for Social Science (SPSS). Proximate analysis revealed significant (p&lt;0.05) differences in moisture, fat, ash, protein, fiber, carbohydrates, and energy content. Manure type significantly (p&lt;0.05) affected protein, carbohydrate, and moisture content. Poultry Manure had superior performance in Cowpea Forage, while Control excelled in Soybean Forage. The anti-nutrient analysis revealed significant (p&lt;0.05) differences in tannin, oxalate, saponin, and phytate content, impacting nutritional quality. Tannin content varied significantly (Groundnut: 65.78 mg/100g, Soybean: 109.78 mg/100g, Cowpea: 37.62 mg/100g), as did oxalate (Groundnut: 393.18 mg/100g, Soybean: 185.20 mg/100g, Cowpea: 357.13 mg/100g), saponin (Groundnut: 5.71 mg/100g, Soybean: 6.63 mg/100g, Cowpea: 6.63 mg/100g), and phytate (Groundnut: 160.89 mg/100g, Soybean: 30.63 mg/100g, Cowpea: 21.22 mg/100g). Vitamin analysis revealed variations in vitamin C (Groundnut: 57.94 mg/100g, Soybean: 58.31 mg/100g, Cowpea: 63.17 mg/100g) and β-carotene (Groundnut: 9.73 mg/100g, Soybean: 9.46 mg/100g, Cowpea: 7.51 mg/100g), indicating nutritional attributes of the studied leguminous forages. Based on the results, the treatment involving poultry dropping, goat dropping, pig dung and control all demonstrated good performance in terms of contributing to the nutritional composition of cowpea, groundnut and soybean. Thus, the use of poultry dropping and pig dung as organic manure for farmers in the region could be recommended.

Investigating the impact of storage duration and temperature on vitamin C in various citrus genotypes: A meta-analysis method

The present work disseminates a solid scientific meta-analysis method to investigate the impact of storage duration and temperature on vitamin C of citrus. This work is initiated by designing of the PICO framework, collecting, and organizing the articles, creating selection criteria, sorting articles, identifying factors influencing moderation effects and sources of diversity, tabulating data, and employing analysis in the form of a linear mixed model. Using this method, we identified 54 distinct studies from a pool of 289 eligible peer-reviewed publications, focusing on variations of vitamin C in citrus. The method provides mean values in both quadratic and linear regression forms.•This method provides a detailed description starting from topic selection to statistical methodologies intended for performing meta-analysis.•All guidelines for conducting this method have been approved by all authors and adhere to the standard PRISMA-P guidelines.•Disseminating this method in a peer-reviewed publication aims to facilitate scholarly discussions and promote transparency, ultimately improving the standard for performing meta-analysis on vitamin C levels in citrus concerning various genotypes, storage temperatures, and durations.

Seasonal Variation in Vitamin D Status Does Not Interfere with Improvements in Aerobic and Muscular Endurance in Conscripts during Basic Military Training.

Considering a lack of respective data, the primary objective of this study was to assess whether seasonal variation in vitamin D status (D-status) affects the extent of improvement in physical performance (PP) in conscripts during basic military training (BMT). D-status, PP and several blood parameters were measured repeatedly in conscripts whose 10-week BMT started in July (cohort S-C; n = 96) or in October (cohort A-C; n = 107). D-status during BMT was higher in S-C compared to A-C (overall serum 25(OH)D 61.4 ± 16.1 and 48.5 ± 20.7 nmol/L, respectively; p < 0.0001). Significant (p < 0.05) improvements in both aerobic and muscular endurance occurred in both cohorts during BMT. Pooled data of the two cohorts revealed a highly reliable (p = 0.000) but weak (R2 = 0.038-0.162) positive association between D-status and PP measures both at the beginning and end of BMT. However, further analysis showed that such a relationship occurred only in conscripts with insufficient or deficient D-status, but not in their vitamin D-sufficient companions. Significant (p < 0.05) increases in serum testosterone-to-cortisol ratio and decreases in ferritin levels occurred during BMT. In conclusion, a positive association exists between D-status and PP measures, but seasonal variation in D-status does not influence the extent of improvement in PP in conscripts during BMT.

The Power of Vitamin D: Is the Future in Precision Nutrition through Personalized Supplementation Plans?

In the last few decades, vitamin D has undeniably been one of the most studied nutrients. Despite our ability to produce vitamin D through sunlight exposure, its presence in several natural food sources and fortified foods, and its widespread availability as a dietary supplement, vitamin D deficiency is a serious public health problem, affecting nearly 50% of the global population. Low serum levels of vitamin D are being associated with increased susceptibility to numerous health conditions, including respiratory infections, mental health, autoimmune diseases, and different cancer types. Although the association between vitamin D status and health is well-established, the exact beneficial effects of vitamin D are still inconclusive and indefinite, especially when considering the prevention and treatment of different health conditions and the determination of an appropriate dosage to exert those beneficial effects in various population groups. Therefore, further research is needed. With constant improvements in our understanding of individual variations in vitamin D metabolism and requirements, in the future, precision nutrition and personalized supplementation plans could prove beneficial.

Response of Carrots (Daucus carota) on the Growth, Yield, and Nutritional Composition to Varying Poultry Manure Rates

AbstractCarrot cultivation in south-eastern Nigeria could reduce the need to transport carrots from northern regions. To explore this, a field experiment with three replications was carried out in Nsukka, south-eastern Nigeria, focusing on four carrot varieties (Carotte Touchon, Touchon Mega, Super Mega, and Touchon France) and three poultry manure rates (0, 10, and 20 t ha−1). The study revealed that Carotte Touchon had the highest root production (11.6 t ha−1) with 20 t ha−1 of manure, followed by 7.5 t ha−1 at 10 t ha−1, while Touchon Mega had the lowest root yield (1.4 t ha−1) in the control group. Proximate quality of carrots was mostly unaffected by the varieties, except for fat content. The study found significant variations in vitamins A, C, and E, phytochemicals (phytate, tannins, and oxalate), and minerals (Fe, Mg, Na, and K) among the varieties, although no impact on Zn and Ca was observed. This research suggests that carrots have substantial growth potential in south-eastern Nigeria, offering a solution to vitamin and mineral deficiencies prevalent in this area. Additionally, Carotte Touchon with either 20 t ha−1 or 10 t ha−1 of poultry manure is recommended for optimal carrot cultivation in this region.

Vitamin C variation in citrus in response to genotypes, storage temperatures, and storage times: A systematic review and meta-analysis

Numerous published studies have highlighted discrepancies in the duration and storage temperature used for preserving vitamin C content on various citrus genotypes worldwide. The present study aimed to analyze the variation in vitamin C content as influenced by citrus genotype, duration, and storage temperature using meta-analysis approaches. Data searching, selection, and tabulation resulted in a comprehensive database constructed from 1412 data points gathered from 54 individual studies, following PRISMA-P guidelines. The vitamin C content varied widely, ranging from 0 to 76.2 mg/100 mL in whole data of citrus fruit. Meta-analysis findings revealed that the duration of storage significantly impacted the vitamin C content in citrus fruits. Specifically, for grapefruit, mandarin, and orange, the length of storage significantly influenced their vitamin C levels (P < 0.01), with a consistent decrease observed over time. The correlation coefficients (R2) were 0.63 for grapefruit, 0.9 for mandarin, and 0.69 for orange. In contrast, no significant difference was found in terms of vitamin C levels between hybrid and lime citrus concerning the impact of storage time. However, other results indicated a significant influence of storage temperature on the variation in vitamin C levels for both citrus and hybrid varieties (P < 0.001). Depending on the genotype, tangerine had significantly lower vitamin C content compared to other varieties, at 16.9 mg/100 mL, with vitamin C ranging from 13.2 to 20.9 mg/100 mL (P < 0.001). The highest vitamin C content was found in lemon and hybrid varieties, around 65.5 (range 59.3–76.2) and 48.3 (range 29.6–75.5), respectively, all in mg/100 mL (P < 0.001). Furthermore, there was a tendency for decreasing vitamin C concentration due to temperature (P = 0.078), while citrus variety experienced a decrease, although not significant. The ideal temperature (15 °C) and duration of storage (56 days) to minimize vitamin C loss in citrus fruits are at their optimum point. In conclusion, the deterioration of vitamin C in citrus fruits is influenced by both temperature and storage duration, and its content is also impacted by the variety of citrus.

Seasonal and sex-related variation in vitamin D status and its association with other biochemical markers in young individuals: A cross-sectional study.

While several studies have investigated the association between vitamin D deficiency and biochemical parameters, the results are still inconsistent and mostly overlook seasonal variations. This study explored the relationships between 25-hydroxy-vitamin D (25(OH)D) concentrations, biochemical markers, and seasonal variation among young males and females. A cross-sectional study was conducted among 203 individuals aged 18-24 years of both sexes residing in Brasilia, Brazil (latitude: 15°S). Sociodemographic variables, season of blood collection, and serum levels of 25(OH)D, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, glycated hemoglobin (HbA1c), glucose, insulin, hs-CRP, parathyroid hormone, ionized calcium, and alkaline phosphatase were included. Descriptive statistics and differences among groups, correlations, and linear regression tests were performed. The mean age of the participants was 21.17±1.7 years, and the mean serum 25(OH)D level was 25.76±7.0 ng/mL. Of the participants, 50.7% had vitamin D insufficiency (20 to 29.9 ng/mL), and 23.2% were vitamin D deficient (≤20 ng/mL). Vitamin D deficiency was higher in the spring (53.2%) and among females (29.5%). In young men with vitamin D insufficiency/deficiency (≤29.9 ng/mL) (n = 49), 25(OH)D levels were inversely correlated with HOMA-β (r = -0.234, p = 0.032) and triglyceride (r = -0.415, p = 0.003) levels. However, there were no significant correlations between 25(OH)D concentrations and biochemical markers among women with insufficient and deficient vitamin D levels. This study found a high prevalence of vitamin D insufficiency/deficiency among young individuals living in Brasília, Brazil, particularly women and during the spring season. Our findings suggest that lower 25(OH)D levels (≤29.9 ng/mL) may be associated with insulin resistance and an increased risk of cardiovascular disease in young men studied. However, further studies with larger representative samples are needed to explore the mechanisms underlying the association between vitamin D and biochemical parameters.

Seasonal Variations in Vitamin D Levels and the Incident Dementia Among Older Adults Aged ≥60 Years in the UK Biobank.

Limited knowledge exists regarding the association between dementia incidence and vitamin D insufficiency/deficiency across seasons. This study aimed to evaluate the impact of seasonal serum vitamin D (25(OH)D) levels on dementia and its subtypes, considering potential modifiers. We analyzed 193,003 individuals aged 60-73 at baseline (2006-2010) from the UK Biobank cohort, with follow-up until 2018. 25(OH)D were measured at baseline, and incident dementia cases were identified through hospital records, death certificates, and self-reports. Out of 1,874 documented all-cause dementia cases, the median follow-up duration was 8.9 years. Linear and nonlinear associations between 25(OH)D and dementia incidence across seasons were observed. In multivariable-adjusted analysis, 25(OH)D deficiency was associated with a 1.5-fold (95% CIs: 1.2-2.0), 2.2-fold (1.5-3.0), 2.0-fold (1.5-2.7), and 1.7-fold (1.3-2.3) increased incidence of all-cause dementia in spring, summer, autumn, and winter, respectively. Adjusting for seasonal variations, 25(OH)D insufficiency and deficiency were associated with a 1.3-fold (1.1-1.4) and 1.8-fold (1.6-2.2) increased dementia incidence, respectively. This association remained significant across subgroups, including baseline age, gender, and education levels. Furthermore, 25(OH)D deficiency was associated with a 1.4-fold (1.1-1.8) and 1.5-fold (1.1-2.0) higher incidence of Alzheimer's disease and vascular dementia, respectively. These associations remained significant across all subgroups. 25(OH)D deficiency is associated with an increased incidence of dementia and its subtypes throughout the year.

Association of vitamin D with HIV infected individuals, TB infected individuals, and HIV-TB co-infected individuals: a systematic review and meta-analysis.

Vitamin D deficiency (VDD) is a worldwide disease. VDD is also associated with an increased risk of HIV-related comorbidities and mortality, and patients have a tendency to develop active tuberculosis compared to those with latent tuberculosis infection. Vitamin D supplementation may modulate HIV replication, improve TB inflammation and reduce progression of HIV-TB co-infection. We meta-analyzed individual participant data from cohort studies, cross-sectional study, and RCTs of vitamin D in HIV group, TB group, and HIV-TB group. The primary outcomes were differences in vitamin D level and VDD prevalence between three groups, the secondary outcomes were CD4 count, HIV viral load, time to sputum smear conversion, time to culture conversion, relapse, morality, and TB score. For vitamin D levels, the overall mean difference (MD) between HIV group and TB group was -0.21 (95% CI, -20.80-20.38; p = 0.9, I2 = 84%), HIV group and HIV-TB group was 0.87 (95% CI, -11.45-13.20; p = 0.89, I2 = 87%), and TB group and HIV-TB group was 1.17 (95% CI, -5.21-7.55; p = 0.72, I2 = 85%). For vitamin D deficiency prevalence, the overall odds ratio (OR) for HIV group versus TB group was 1.23 (95% CI, 0.46-3.31; p = 0.68; I2 = 70%), HIV group versus HIV-TB group was 1.53 (95% CI, 1.03-2.29; p = 0.04; I2 = 0%), and TB group versus HIV-TB group was 0.85 (95% CI, 0.61-1.20; p = 0.36; I2 = 22%). In HIV-TB group, the overall OR for vitamin D group versus placebo group was 0.78 (95% CI, 0.34-1.67; p = 0.52; I2 = 60%). Our findings indicated that there were no variations in vitamin D levels between three groups. The prevalence of vitamin D deficiency was higher in the HIV-TB group than in the HIV group. Additionally, the administration of vitamin D supplements did not have obvious impact on CD4 count and viral load. Likewise, vitamin D had no effect on time to sputum smear conversion, time to culture conversion, relapse, 12-month morality, and TB score.

Evidence supports a causal association between allele-specific vitamin D receptor binding and multiple sclerosis among Europeans

Although evidence exists for a causal association between 25-hydroxyvitamin D (25(OH)D) serum levels, and multiple sclerosis (MS), the role of variation in vitamin D receptor (VDR) binding in MS is unknown. Here, we leveraged previously identified variants associated with allele imbalance in VDR binding (VDR-binding variant; VDR-BV) in ChIP-exo data from calcitriol-stimulated lymphoblastoid cell lines and 25(OH)D serum levels from genome-wide association studies to construct genetic instrumental variables (GIVs). GIVs are composed of one or more genetic variants that serve as proxies for exposures of interest. Here, GIVs for both VDR-BVs and 25(OH)D were used in a two-sample Mendelian Randomization study to investigate the relationship between VDR binding at a locus, 25(OH)D serum levels, and MS risk. Data for 13,598 MS cases and 38,887 controls of European ancestry from Kaiser Permanente Northern California, Swedish MS studies, and the UK Biobank were included. We estimated the association between each VDR-BV GIV and MS. Significant interaction between a VDR-BV GIV and a GIV for serum 25OH(D) was evidence for a causal association between VDR-BVs and MS unbiased by pleiotropy. We observed evidence for associations between two VDR-BVs (rs2881514, rs2531804) and MS after correction for multiple tests. There was evidence of interaction between rs2881514 and a 25(OH)D GIV, providing evidence of a causal association between rs2881514 and MS. This study is the first to demonstrate evidence that variation in VDR binding at a locus contributes to MS risk. Our results are relevant to other autoimmune diseases in which vitamin D plays a role.

A Comprehensive Review of the Immunomodulatory Effects of Vitamin D in Sepsis.

Sepsis remains a critical global health challenge characterised by a dysregulated immune response to infection, leading to systemic inflammation and organ dysfunction. This review examines the immunomodulatory effects of Vitamin D in sepsis, focusing on its regulation of immune cell function, modulation of cytokine production, and enhancement of antimicrobial responses. While the potential of Vitamin D as an adjunctive therapy in sepsis management is evident, challenges such as variability in Vitamin D status, uncertainties regarding optimal dosages and patient heterogeneity, and potential adverse effects require careful consideration. The review highlights the implications for future research and clinical practice, emphasising the need for standardised measurement protocols, elucidation of optimal supplementation strategies, and integration of Vitamin D assessments into routine care. Despite the complexities, Vitamin D emerges as a promising avenue for personalised interventions in sepsis, necessitating ongoing research collaboration and evidence-based guidelines to harness its full therapeutic potential and improve clinical outcomes.

Cytochrome P450 Family 4F2 and 4F11 Haplotype Mapping and Association with Hepatic Gene Expression and Vitamin K Hydroxylation Activity.

This study evaluated the underlying mechanistic links between genetic variability in vitamin K metabolic pathway genes (CYP4F2 and CYP4F11) and phylloquinone hydroxylation activity using genotype- and haplotype-based approaches. Specifically, we characterized genetic variability in the CYP4F2/CYP4F11 locus and compared common single allele genotypes and common haplotypes as predictors of hepatic gene expression, enzyme abundance, and phylloquinone (VK1) ω-hydroxylation kinetics. We measured CYP4F2 and CYP4F11 mRNA levels, CYP4F2 and CYP4F11 protein abundances, and the VK1 concentration-dependent ω-hydroxylation rate in matched human liver nucleic acid and microsome samples, utilizing a novel in vitro population modeling approach. Results indicate that accounting for the CYP4F2*3 allele alone is sufficient to capture most of the genetic-derived variability in the observed phenotypes. Additionally, our findings highlight the important contribution that CYP4F11 makes toward vitamin K metabolism in the human liver.