Plasma Concentrations Of Vitamin Research Articles

Vitamin E and risk of first stroke in general hypertensive patients: a nested case–control study

Background: Epidemiological studies on the association between levels of plasma vitamin E and first stroke risk are inconclusive. Methods: A nested, case–control study was conducted utilizing data on 115,337 hypertensive patients from the H-type Hypertension and Stroke Prevention and Control Project. The current analysis comprised 2193 cases of first stroke and 2193 controls matched for age, sex, and study site. Results: The mean plasma concentration of vitamin E was 12.37 (3.61) μg/mL. The smoothing curve showed a linear correlation between plasma vitamin E levels and the risk of the first stroke. Hypertensive patients with plasma vitamin E levels ≥14.1 μg/mL (Q4) had an increased risk of first stroke (adjusted odds ratios [OR]: 1.18; 95% confidence interval [CI]: 1.01, 1.37) compared with those with plasma vitamin E < 14.1 μg/mL (Q1–Q3). Sub-group analysis revealed that the relationship between plasma vitamin E (≥14.1.1 vs. P interaction = 0.035). Conclusions: This study suggests that higher levels of plasma vitamin E are associated with an elevated risk of first stroke among Chinese hypertensive patients.

Four-week administration of an energy and protein dense oral nutritional supplement improves micronutrient concentrations but does not completely correct deficiencies in institutionalized malnourished older adults.

Poor food intake is common among elderly living in nursing homes, leading to micronutrient deficiency (MD). There are no recommendations for the management of MD in malnourished older adults. We conducted a single arm, open-label, multicenter interventional study in institutionalized malnourished older adults to describe the effect of a 4-week daily energy and protein dense oral nutritional supplementation (ONS, 600 kcal, 30 g protein per unit) containing 50% of the recommended daily micronutrient intake on micronutrient status. Plasma concentrations of vitamins (A, B9, B12, C, E), magnesium (Mg), selenium (Se) and zinc (Zn), and erythrocyte vitamin B9 were measured at baseline and after 4 weeks. Forty-six participants completed the study (age 87.4 ± 6.6). At baseline, the most frequent MD were Se (48%), Zn (35%), Mg (24%) and vitamin C (24%). Plasma concentrations of vitamins B9, B12, C and E, Mg, Se and Zn significantly increased and the proportion of subjects with at least one MD decreased (p = 0.006). However, after 4 weeks, 40% of subjects still had at least one MD. ONS consumption improved micronutrient status but did not correct MD in all participants. Our data suggest that the prescription of vitamin, mineral and trace element supplementation should be considered in institutionalized malnourished older adults in addition to high energy and high protein ONS.

Association of Plasma Vitamins and Carotenoids, DNA Methylation of LCAT, and Risk of Age-Related Macular Degeneration.

Dysregulation of lipid metabolism has been implicated in age-related macular degeneration (AMD), the leading cause of blindness among the elderly. Lecithin cholesterol acyltransferase (LCAT) is an important enzyme responsible for lipid metabolism, which could be regulated by DNA methylation during the development of various age-related diseases. This study aimed to assess the association between LCAT DNA methylation and the risk of AMD, and to examine whether plasma vitamin and carotenoid concentrations modified this association. A total of 126 cases of AMD and 174 controls were included in the present analysis. LCAT DNA methylation was detected by quantitative real-time methylation-1specific PCR (qMSP). Circulating vitamins and carotenoids were measured using reversed-phase high-performance liquid chromatography (RP-HPLC). DNA methylation of LCAT was significantly higher in patients with AMD than those in the control subjects. After multivariable adjustment, participants in the highest tertile of LCAT DNA methylation had a 5.37-fold higher risk (95% CI: 2.56, 11.28) of AMD compared with those in the lowest tertile. Each standard deviation (SD) increment of LCAT DNA methylation was associated with a 2.23-fold (95% CI: 1.58, 3.13) increased risk of AMD. There was a J-shaped association between LCAT DNA methylation and AMD risk (Pnon-linearity = 0.03). Higher concentrations of plasma retinol and β-cryptoxanthin were significantly associated with decreased levels of LCAT DNA methylation, with the multivariate-adjusted β coefficient being -0.05 (95% CI: -0.08, -0.01) and -0.25 (95% CI: -0.42, -0.08), respectively. In joint analyses of LCAT DNA methylation and plasma vitamin and carotenoid concentrations, the inverse association between increased LCAT DNA methylation and AMD risk was more pronounced among participants who had a lower concentration of plasma retinol and β-cryptoxanthin. These findings highlight the importance of comprehensively assessing LCAT DNA methylation and increasing vitamin and carotenoid status for the prevention of AMD.

Is Cataract in Patients under 60 Years Associated with Oxidative Stress?

Oxidative stress is considered as a possible factor in the genesis of cataract. The study aimed to determine the systemic antioxidant status in cataract patients under 60 years. We studied 28 consecutive cataract patients, mean of 53 years (SD = 9.2), a range of 22-60 and 37 controls. In erythrocytes, activity of antioxidant enzymes was determined: superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), in contrast with plasma concentrations of vitamin A and E. Conjugated dienes (CD) level and protein carbonyls (PC) concentration were also determined in plasma. Malondialdehyde (MDA) concentrations in erythrocytes and plasma were also measured. SOD and GPx activity and vitamin A and E concentrations were lower in cataract patients (p = 0.000511, 0.02, 0.022, and 0.000006, respectively). MDA plasma and erythrocytes concentrations were higher in cataract patients (p = 0.000001 and 0.0000001, respectively). PC concentration was higher in cataract patients than in controls (p = 0.00000013). There were statistically significant correlations between oxidative stress markers both in the cataract patients group as well as in the control group. Cataract incidence in patients under 60 years seems to be accompanied by enhanced lipid peroxidation and protein oxidation, as well as antioxidant defense depletion. Thus, supplementation with antioxidants could be beneficial in this group of patients.

Effect of increasing levels of fat-soluble and water-soluble vitamins on improving performance and plasma vitamin concentration in modern hybrids pig’s growth and finishing phase

ABSTRACT The objective was to evaluate the supplementation of fat-soluble and water-soluble vitamins on the performance and plasma concentrations of vitamins in modern hybrids pigs. A total of 144 commercial hybrid castrated male, 43.531 ± 1.099kg, were used in a randomized block design with six treatments, eight replicates and three animals per pen. The experimental treatments were different vitamin supplementation levels - 0, 25, 50, 75, 100, and 125% of the recommended by Rostagno et al. (2011) for male pigs in growth I (40 to 50kg), growth II (50 to 70kg), and finishing I (70 to 90kg) phases. For growth phases I and II, a linear effect (P<0.05) due to increase in vitamin supplementation was observed on performance. For finishing phase I and total phase, a linear effect (P<0.05) was observed with increased final average weight (FAW) and improved feed conversion ratio (FCR). For average daily weight gain (ADWG) and average daily feed intake (ADFI) a quadratic effect was observed (P<0.05). A linear (P<0.05) increase in plasmatic α-tocopherol and B12 was observed with the 125%. Thus, it is concluded that the 125% vitamin supplementation improved performance of modern hybrids pigs (40 to 90kg).

Early renal impairment affects hormonal regulators of calcium and bone metabolism and Wnt signalling and the response to vitamin D supplementation in healthy older adults

Bone and renal metabolism are regulated by common factors and there is extensive cross-talk between these organs (the ‘renal-bone-axis’). Ageing is associated with physiological changes including reduced bone mass, renal function and tissue sensitivity to regulatory hormones, impacting the renal-bone axis. We aimed to investigate the influence of estimated Glomerular Filtration Rate (eGFR) on plasma concentrations of vitamin D metabolites, Wnt signalling and bone metabolism in a dose ranging vitamin D3 RCT (12,000 IU, 24,000 IU, 48,000 IU/month for 1 year; n = 379, >70 y) with a baseline eGFR > 30 mL/min/1.73 m2. Participants were categorised on basis of eGFR (≥60 or mL/min/1.73 m2) based on 5 commonly used algorithms for eGFR. Differences between eGFR categories were tested with ANCOVA. Before supplementation commenced, a lower eGFR was associated with significantly higher concentrations of c-terminal and intact Fibroblast Growth Factor-23 (cFGF23; iFGF23), intact Parathyroid Hormone (iPTH) and Sclerostin (SOST) and lower Klotho, 1,25-dihydroxy Vitamin D (1,25(OH)2D) and Dickkopf-related Protein 1 (DKK1) concentrations. Differences between eGFR groups in 25-hydroxy Vitamin D (25(OH)D), 24,25-dihydroxy Vitamin D (24,25(OH)2D) and iPTH were only detected with eGFR based on Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Modification in Diet for Renal Disease (MDRD-4) algorithms. Differences in Bone Mineral Density and Content (BMD; BMC) and bone turnover markers were detected only with Cockcroft-Gault (CG). Pre- and post- supplementation comparisons showed differences in the response to supplementation by eGFR group. Plasma 25(OH)D, 24,25(OH)2D, 1,25(OH)2D and DKK1 increased and iPTH and C-terminal telopeptide (CTX) decreased in both groups. Plasma iFGF23, bone specific alkaline phosphatase (BAP) and Procollagen 1 intact N-terminal Propeptide (PINP) increased and phosphate decreased only in the group with eGFR ≥ 60 mL/min/1.73 m2. Findings were largely consistent across all eGFR algorithms. Post-supplementation, cFGF23, iFGF23, iPTH and SOST remained significantly higher in the lower eGFR group. Plasma 1,25(OH)2D and Klotho did no longer differ between eGFR groups. This was found for all eGFR algorithms, with the exception of iPTH and iFGF23, which were not significantly different with eGFR based on CG. Differences in BMD and BMC were detected with CKD-EPI-creatinine and MDRD-4 but not GC. This study showed that even a moderate decline in eGFR is associated with alterations in vitamin D metabolism, Wnt signalling and bone turnover markers. Renal function influenced the response to vitamin D supplementation. Supplementation increased Vitamin D metabolites in the group with moderate renal impairment to concentrations comparable to those found in the group with normal renal function. However, although CTX decreased, an increase in bone formation markers was not found in the group with eGFR 60 mL/min/1.73 m2. In conclusion, vitamin D supplementation had beneficial effects on markers of the renal-bone axis in older people with both normal and impaired renal function.

Vitamin D Deficit as Inducer of Adenotonsillar Hypertrophy in Children with Obstructive Sleep Apnea-A Prospective Case-Control Study.

(1) Objective: This prospective case-control study aimed to assess the level of serum vitamin D comparing pediatric non-allergic patients with obstructive sleep apnea (OSA) and healthy controls. (2) Methods: The period of the enrollment was from November 2021 to February 2022. Children with uncomplicated OSA caused by adenotonsillar hypertrophy (ATH) were recruited. Allergy was excluded by skin prick test (SPT), and the determination of serum IgE level using ELISA test. Plasma concentration of 25-hydroxy vitamin D (25-OHD) was quantitatively determined; then, the vitamin D concentration in patients was compared with healthy controls matched for sex, age, ethnicity, and characteristics. (3) Results: Plasma 25-OHD levels were significantly lower in patients than in healthy subjects (mean 17 ng/mL, 6.27 DS, range 6-30.7 ng/mL, vs. mean 22 ng/mL, 9.45 DS, range 7-41.2 ng/ ml; p < 0.0005). The prevalence of children with vitamin D deficiency was significantly higher in the ATH group than controls. The plasma 25-OHD level did not change following the ATH clinical presentation (III or IV grade according to the Brodsky scale), while the different categories of 25-OHD status (insufficiency, deficiency, and adequacy) in the ATH group were statistically significantly different (p < 0.001) from healthy controls. (4) Conclusions: This study identified statistically significant differences between the ATH group and control regarding the plasma concentration of vitamin D; this data, despite not being directly linkable to the lymphoid tissue hypertrophy (p-value not significant), might suggest a negative effect of vitamin D deficit on the immune system.

A blend of functional amino acids and grape polyphenols improves the pig capacity to cope with an inflammatory challenge caused by poor hygiene of housing conditions

BackgroundDietary supplementation with a blend of functional amino acids (AA) and grape extract polyphenols contributes to preserve intestinal health and growth performance of piglets during the post-weaning period. In the present experiment, we assessed if a supplementation with a mix of AA and grape extract polyphenols during the post-weaning period would persist to improve the pig capacity to cope with a subsequent challenge caused by poor hygiene of housing conditions. Eighty pigs weaned at 28 days of age were fed a standard diet supplemented (AAP) or not (CNT) with 0.2% of a blend of AA (glutamine, arginine, cystine, valine, isoleucine, and leucine) and grape extract polyphenols during the post-weaning period (from week 0 to 6). At week 6, pigs were transferred to a growing unit where 50% of pigs previously fed AAP and CNT diets were housed in good and the other 50% in poor hygiene conditions for 3 weeks (from week 7 to 9; challenge period). All pigs were fed a standard growing diet that was not supplemented with AAP. We measured pig growth performance, plasma indicators of inflammation, digestive integrity, and oxidative status, and scored fecal consistency. Differences were considered significant at P ≤ 0.05.ResultsOne week post-weaning, pigs fed AAP had lower plasma concentrations of haptoglobin than CNT pigs (P = 0.03). Six weeks post-weaning, plasma concentrations of diamine oxidase (DAO) were lower (P = 0.03) whereas those of vitamin E and A were greater (P ≤ 0.05) in pigs fed AAP compared to CNT pigs. The prevalence of diarrhea was higher in CNT pigs compared to AAP pigs (P < 0.01). During the challenge period, only pigs previously fed CNT diet had lower growth rate in poor than good conditions (P ≤ 0.05). They had also greater plasma concentrations of haptoglobin and oxidative stress index (OSI) and lower plasma concentrations of vitamin E in poor than good hygiene conditions (P ≤ 0.05).ConclusionsPigs fed AAP diet during post-weaning had less diarrhea and plasma concentrations of a digestive integrity marker, as well as greater plasma concentrations of antioxidant indicators during the post-weaning period. The beneficial effects of AAP supplementation persisted after the post-weaning period as evidenced by the absence of effects of the hygiene challenge on growth and health indicators in pigs previously fed APP. This clearly indicated a greater ability of pigs fed AAP to cope with the poor hygiene conditions.

A Prenatal Multiple Micronutrient Supplement Produces Higher Maternal Vitamin B-12 Concentrations and Similar Folate, Ferritin, and Zinc Concentrations as the Standard 60-mg Iron Plus 400-μg Folic Acid Supplement in Rural Bangladeshi Women

Background: The effects of prenatal food and micronutrient supplementation on maternal micronutrient status are not well known.Objective: We compared the efficacy and effectiveness of 3 different micronutrient supplements on maternal micronutrient status when combined with food supplementation.Methods: In the MINIMat (Maternal and Infant Nutrition Intervention, Matlab) trial in Bangladesh, 4436 pregnant women were randomly assigned to daily intake of 3 types of micronutrient capsules: 30 mg Fe and 400 μg folic acid (Fe30F), 60 mg Fe and 400 μg folic acid (Fe60F), or multiple micronutrient supplements (MMNs) combined with early (week 9 of pregnancy) or usual (week 20 of pregnancy) food supplementation in a 2 by 3 factorial design. Plasma concentrations of vitamin B-12, folate, ferritin, and zinc were analyzed before the start of micronutrient supplementation (week 14) and at week 30 of pregnancy in 641 randomly selected women. An electronic monitoring device was used to measure the number of capsules taken. The effectiveness of food and micronutrient regimens as well as efficacy per capsule in maternal micronutrient status were analyzed by ANOVA and general linear models.Results: At week 30 of pregnancy, women in the MMN group had higher geometric mean concentrations of vitamin B-12 than women in the Fe60F group (119 compared with 101 pmol/L, respectively); no other differences in effectiveness of micronutrient and food regimens were observed. A dose-response relation between the number of capsules taken and concentrations of folate and ferritin was observed for all micronutrient supplements. Fe30F had lower efficacy per capsule in increasing ferritin concentrations within the first tertile of capsule intake than did Fe60F and MMNs. Because ferritin reached a plateau for all types of micronutrient supplements, there was no difference between the regimens in their effectiveness.Conclusion: Compared with Fe60F, MMNs produced higher maternal vitamin B-12 and similar ferritin and folate concentrations in Bangladeshi women. The MINIMat trial was registered at isrctn.org as ISRCTN16581394.

Multifactorial hypovitaminosis D among women in the South-East Oases of Morocco.

This study assessed the vitamin D status among women in the Draa-Tafilalet region and its relationship with clinical, anthropometric, and behavioral parameters. The study was carried out with 233 women in consultation at five urban and rural health centers in the South-East region of Morocco. The data collected relate to age, monthly income, educational level, BMI, body fat percentage, daily sun exposure, physical activity level, veil wear, and skin color. The plasma determination of vitamin D was measured by immunofluorescence. Statistical analyses were performed using Python and Jamovi. The median 25(OH)D plasma concentration was 9.95ng/mL (IQR: 8-13.18). A total of 50.64% of women had 25(OH)D levels below 10ng/ml and 47.21% had levels between 10 and 30ng/mL. Statistical tests showed an association between hydroxyvitamin D plasma levels and age (r = - 0.139; p = 0.034), monthly income (p = 0.001), BMI (r = - 0.200; p = 0.002), body fat percentage (r = - 0.131; p = 0.049), daily sun exposure (r = 0.165; p = 0.012), and skin color (p < 0.001). Binomial logistic regression showed that darker skin was associated with vitamin D deficiency (< 10ng/mL). It also showed that high income and longer sun exposure could be protecting factors against vitamin D deficiency. The plasma concentrations of vitamin D in women in the Draa-Tafilalet region were low compared to expected results for a high sunshine time area.

Effect of Diet and Supplementation on Serum Vitamin C Concentration and Antioxidant Activity in Dialysis Patients

Loss of vitamin C, especially in conjunction with an inadequate supply, can lead to decreased plasma concentrations of vitamin C. This in turn can lead to overt or subclinical deficiency. The present study aimed to evaluate the effects of diet and supplementation on vitamin C concentrations and serum antioxidant activity (FRAP) in hemodialysis (HD) patients. Sixty-eight HD patients participated in the study. In all of them, the diet was initially determined, and they were divided into five groups according to the diet and supplementation used. Group 1 received an unchanged diet, considered by them to be optimal; in group 2, the standard diet used in HD patients was introduced; in group 3, a standard diet enriched with natural antioxidants was employed; in group 4, a standard diet as in group 2 was used, but enriched with supplements (vitamin C, vitamin E, Se, and Zn). In contrast, group 5 consisted of HD patients with coexisting diabetes. Vitamin C serum levels were determined by high-performance liquid chromatography HPLC and antioxidant activity by The Ferric Reducing Ability of Plasma FRAP. The study shows that a well-chosen diet can slow the build-up of malnutrition and increase antioxidant activity as measured by the FRAP method in the blood of hemodialysis patients. Vitamin C supplementation can improve antioxidant status in hemodialysis patients. * The results presented in this paper complement our study, which assessed the effect of diet on the activity of erythrocyte antioxidant enzymes: Catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px), but also on the concentrations of non-enzymatic antioxidants (tocopherols, carotenoids, and vitamin C) in hemodialysis patients. In the study, plasma malondialdehyde (MDA) concentrations were assessed as an indicator of oxidative damage.

Acquired night blindness due to rod dysfunction after long‐term haemodialysis

AbstractPurpose: To report the clinical findings in 10 patients who developed night blindness after long‐term haemodialysis.Methods: The medical charts of the 10 patients were examined. The fundus photographs, spectral‐domain optical coherence tomographic (SD‐OCT) images, full‐field ERGs, and blood chemistry panels were analysed.Results: The mean age of the 10 patients (4 men) at the time of diagnosis was 70 years. The mean duration of the haemodialysis was 23 years. The visual acuity of the patients was preserved at 20/30 or better except in 1 eye. Ophthalmoscopy showed white flecks that were scattered over the midperipheral retina in all the eyes. SD‐OCT showed mild macular degeneration in 5 eyes. The scotopic ERGs elicited by dim flashes were absent, and those elicited by bright flashes had negative waveforms. The photopic ERGs were relatively well preserved. These data indicated a rod‐specific dysfunction that may account for the night blindness. The plasma concentration of vitamin A was within the normal range in 4 of the patients and slightly lower than the normal limit in 1 of the patients. Administration of vitamin A was performed for 1 patient, and the symptom of night blindness and scotopic ERGs were improved 3 months later.Conclusions: Long‐term haemodialysis can be associated with the night blindness that may be caused by vitamin A deficiency, even though the plasma concentration of vitamin A in these patients was within the normal range.

The role of serum vitamin 25(OH)D concentration in the Covid-19 pandemic in children.

The ongoing Coronavirus disease 19 (Covid-19) pandemic and associated mortality in children led to an effort to address risk factors and develop protective measures. Observational studies in adults showed that vitamin D deficiency is associated with Covid-19 severity. The aim of this review was to summarise data regarding the role of serum vitamin 25(OH)D concentration in the severity of Covid-19 and the associated multisystem inflammatory syndrome in children (MIS-C). Many studies noted lower concentrations of vitamin 25(OH)D in children with Covid-19 compared with healthy controls; however, studies that assessed vitamin 25(OH)D suboptimal concentrations as a risk factor for Covid-19 severity were scarce. There was no high-quality evidence that vitamin 25(OH)D concentrations are associated with Covid-19 severity. Similarly, for MIS-C, a few studies with a small number of patients found that vitamin D deficiency was associated with more severe MIS-C. Vitamin D has many immunomodulatory actions and is consumed in the immunomodulatory cells, especially in infections such as the Covid-19 which is associated with increased inflammation and cytokine storm. Therefore, decreased concentrations of plasma vitamin 25(OH)D have been proposed to be the result of vitamin use by immunomodulatory cells in severe Covid-19, rather than a predisposing factor. In conclusion, the available data cannot prove that vitamin D deficiency is a risk factor for severe Covid-19 disease. More studies, of prospective design, are needed to investigate the role of this marker independently of other risk factors.

Correlation between vitamin d andcovid-19 patients

Vitamin D deficiency is suspected to cause possible complications in COVID-19 patients or they might be provided with a poor prognosis. However, this same vitamin D in excess is capable of causing toxicity. The presentstudy was based on a qualitative/quantitative study carried out from July to September, 2021 .Patients who tested positive for COVID-19 and who sought medical appointment in a private general practice in the city of Caçador,state of Santa Catarina (SC), were selected. The sample consisted of 54 patients who sought ambulatory care and who had a positive diagnosis for COVID-19. Vitamin D levels were found to beeither insufficient or deficient in most patients. However, the plasma concentration of vitamin D in these patients cannot be related to the positivity of the disease or hospitalization. What can be safely concluded is that vitamin D has numerous proven benefits, such as maintaining the cells of the immune system and, thus, preventing infectious diseases.

Retrospective Analysis of Cataract Formation and Nutritional Etiology in a Managed Collection of Parakeet Auklets (Aethia psittacula).

The parakeet auklet (Aethia psittacula) is a piscivorous seabird with a natural diet of various invertebrate and teleost species, which is challenging to replicate in a managed collection. A high prevalence of early onset cataracts was observed in a managed collection of parakeet auklets at the North Carolina Zoo (Asheboro, NC, USA), which was hypothesized to be related to inappropriate vitamin A and E levels. From 1994 to 2002, these parakeet auklets were offered dietary supplementation comprising Vita-Zu small bird tablets. In June 2002, the birds were transitioned to only Thiamin-E paste (vitamin E and thiamin only). Plasma samples were collected from birds with and without cataracts from 1998 to 2005 and submitted for vitamin A (retinol) and vitamin E (α-tocopherol) analysis. Food items comprising the birds' diet were also evaluated for vitamin content. This information was combined with clinical and necropsy data from medical records from 1994 to 2015. A total of 78% of birds (39/50) developed cataracts, with a median age of onset of 7 years (range, 2-12 years). Cataracts ranged from incipient to hypermature during both routine ophthalmic examinations and postmortem evaluations. The median (range) of plasma retinol and α-tocopherol values were 1.99 µg/mL (0.20-6.68 µg/mL) and 15.39 µg/mL (3.40-96.27 µg/mL), respectively. There were no significant differences in plasma concentrations of vitamins based on the animals' sex, origin, presence of cataracts, or administered vitamin supplementation product. No other etiologies for cataract development were identified in the population. Further research in free-ranging parakeet auklet nutrition and cataract occurrence is warranted for continued species collection management.

Effect of Diet Supplementation with the Mycotoxin Binder Montmorillonite on the Bioavailability of Vitamins in Dairy Cows.

The objective of this study was to determine the effect of the mycotoxin binder montmorillonite (MMT) supplemented in the diet of dairy cows on the bioavailability of vitamins A, D, E, B1 and B6. Six multiparous Holstein-Friesian cows were used in a crossover design with two periods. Treatments were a control diet with or without MMT. Vitamins were infused individually into the abomasum through the ruminal cannula. Blood samples were collected from the jugular vein at 0, 1, 2, 3, 4, 6, 9, 12, 24 and 48 h after the administration of each vitamin. Results showed that vitamin A reached maximal concentration (Tmax) at 5.3 h after dosing, the maximal concentration (Cmax) was 1.2 times higher than the basal concentration (Cbasal), and the area under the curve (AUC) was 739 arbitrary units. Vitamin B6 reached the Tmax at 13 h after dosing, the Cmax was 1.4 times higher than the Cbasal, and the AUC was 222 arbitrary units. No differences were observed in Cbasal, Tmax, Cmax and AUC of vitamin A and B6 between control vs. MMT-supplemented cows. Plasma concentrations of vitamins D, E and B1 had no concentration peaks, and were not affected by MMT addition. The lack of a response suggests that their plasma concentration may be tightly regulated. Results of this study do not show evidence that MMT affects the bioavailability of vitamins A and B6 in vivo.

Association between a SLC23A2 Gene Variation, Plasma Vitamin C Levels, and Risk of Different Diseases

Background: Vitamin C is an important plasma water-soluble antioxidant that plays an essential role in the absorption of iron, detoxification of exogenous compounds, and remaking vitamin E for the protection of lipid membranes. In addition, vitamin C is essential in the synthesis of collagen. Vitamin C concentrations of plasma are determined by dietary intake and genetic factors. Ascorbic acid is the functional form of vitamin C, which is transported into the cell through sodium vitamin C transporters (SVCTs). There are two forms of SVCTs which are SVCT1 encoded by the SLC23A1 gene and SVCT2 encoded by the SLC23A2. The SLC23A2 gene locus on human chromosome 20P12. It expresses in most human tissues, except lung and skeletal muscle that it is important in regulating the intracellular concentration of ascorbic acid to protect the cell from oxidative stress and promote type 1 collagen maturation. Maintaining proper concentrations of plasma and cellular vitamin C concentration is important for the normal metabolic function of the body and preventing several diseases. In the contrast, a low concentration of vitamin C caused by SLC23A2 variation can cause several chronic diseases. Our systematic review discusses four diseases related to the variation of SLC23A2 gene and plasma vitamin C levels which are glaucoma, acute coronary syndrome among women, gastric cancer, and HPV16-associated head and neck cancer.&#x0D; Methods: By using NCBI databases, specifically GenBank to analyze DNA sequence and mRNA sequence of SLC23A2 gene. GenBank file format was helpful to extract an accession number of the gene, number of amino acids, number of exons and introns, and length of nucleotides. FASTA format was also useful to retrieve the nucleotide sequence and get the function of the protein. BLAST was used to compare the protein product of the SLC23A2 gene between humans and Macaca mulatta (Rhesus monkey).&#x0D; Results: the accession number of the SLC23A2 gene was NC_000020.11, the number of exons found was 18, and the gene was located in chromosome 20. This gene encodes one of the two required transporters, and the encoded protein accounts for tissue-specific uptake of vitamin C. This gene had an official symbol of SLC23A1. And they found a significant association between the single-nucleotide polymorphism (SNP) rs1279683 (A &gt; G) in SLC23A2 and an increased risk of POAG in homozygous G allele (GG) carriers. Also, POAG patients with this SNP appear to have a significantly lower level of plasma vitamin C compared to other genotypes. Finally, many organisms have the same gene, such as dogs, mice, rats, and chickens.&#x0D; Conclusion: there is a significant association between SLC23A2 gene mutation, increased risk for vitamin C deficiency, and several diseases. SNP in the SLC23A2 gene was significantly associated with a higher risk of POAG in GG allele carriers as well as lower plasma vitamin C concentration.

Association between fat-soluble vitamins and self-reported health status: a cross-sectional analysis of the MARK-AGE cohort.

Self-rated health (SRH) is associated with higher risk of death. Since low plasma levels of fat-soluble vitamins are related to mortality, we aimed to assess whether plasma concentrations of vitamins A, D and E were associated with SRH in the MARK-AGE study. We included 3158 participants (52 % female) aged between 35 and 75 years. Cross-sectional data were collected via questionnaires. An enzyme immunoassay quantified 25-hydroxyvitamin D and HPLC determined α-tocopherol and retinol plasma concentrations. The median 25-hydroxyvitamin D and retinol concentrations differed significantly (P < 0·001) between SRH categories and were lower in the combined fair/poor category v. the excellent, very good and good categories (25-hydroxvitamin D: 40·8 v. 51·9, 49·3, 46·7 nmol/l, respectively; retinol: 1·67 v. 1·75, 1·74, 1·70 µmol/l, respectively). Both vitamin D and retinol status were independently associated with fair/poor SRH in multiple regression analyses: adjusted OR (95 % CI) for the vitamin D insufficiency, deficiency and severe deficiency categories were 1·33 (1·06-1·68), 1·50 (1·17-1·93) and 1·83 (1·34-2·50), respectively; P = 0·015, P = 0·001 and P < 0·001, and for the second/third/fourth retinol quartiles: 1·44 (1·18-1·75), 1·57 (1·28-1·93) and 1·49 (1·20-1·84); all P < 0·001. No significant associations were reported for α-tocopherol quartiles. Lower vitamin A and D status emerged as independent markers for fair/poor SRH. Further insights into the long-term implications of these modifiable nutrients on health status are warranted.

Acquired night blindness due to rod dysfunction after long-term hemodialysis.

To report the clinical findings in 6 patients who developed night blindness after long-term hemodialysis. Retrospective case series. The medical charts of the 6 patients were examined. The fundus photographs, spectral-domain optical coherence tomographic (SD-OCT) images, full-field ERGs, and blood chemistry panels were analyzed. The mean age of the 6 patients (4 men) at the time of diagnosis was 69.1 ± 5.9years. The mean duration of the hemodialysis was 21.8 ± 13.4years (7-41years). The visual acuity of the patients was preserved at 20/30 or better except in 1 eye. Ophthalmoscopy showed white flecks that were scattered over the midperipheral retina in all the eyes. SD-OCT showed mild macular degeneration in 5 eyes. The scotopic ERGs elicited by dim flashes were absent, and those elicited by bright flashes had negative waveforms. The photopic ERGs were relatively well preserved. These data indicated a rod-specific dysfunction that may account for the night blindness. The plasma concentration of vitamin A was within the normal range in 4 of the patients and slightly lower than the normal limit in 1 of the patients. Administration of vitamin A was performed for 1 patient, and the symptom of night blindness and scotopic ERGs were improved 3months later. Long-term hemodialysis can be associated with the night blindness that may be caused by vitamin A deficiency, even though the plasma concentration of vitamin A in these patients was within the normal range.

Vitamin D Receptor Gene Polymorphism and Vitamin D Status in Population of Patients with Cardiovascular Disease-A Preliminary Study.

The association between vitamin D receptor (VDR) polymorphism and the risk of cardiovascular diseases (CVD) remains unclear. This study aimed to assess a relationship between the VDR genotypes, plasma concentrations of vitamin D metabolites, and the occurrence of cardiovascular and metabolic disorders. Fifty-eight patients treated for various cardiological afflictions were included. Identification of VDR polymorphisms: ApaI, TaqI, BsmI, and FokI were carried out using the PCR-RFLP method. Plasma concentrations of 25-hydroxyvitamin-D2, 25-hydroxyvitamin-D3, and 3-epi-25-hydroxyvitamin D3 were assessed by the UPLC-MS/MS method. Lower incidence of BsmI AA genotype in the studied patients was observed compared with healthy controls, but the difference was insignificant. Among patients with the TT genotype, frequency of hypertension was higher than among carriers of other ApaI genotypes (p < 0.01). In addition, carriers of the TT ApaI, TC TaqI, and GA BsmI genotypes had an increased risk of obesity, while the presence of the FokI TT genotype was associated with a higher incidence of heart failure and hypertension. In conclusion, the BsmI AA genotype can be protective against CVD, but this observation needs study on a larger group of patients. Particular VDR genotypes were associated with 25-hydroxyvitamin-D levels, and the mechanism of this association should be further investigated.