The vitamin B6 paradox: Supplementation with high concentrations of pyridoxine leads to decreased vitamin B6 function

High-dose Vitamin-B6 reduces sensory over-responsivity

BACKGROUND

Sensory reactivity differences are experienced by between 5% and 15% of the population, often taking the form of sensory over-responsivity (SOR), in which sensory stimuli are experienced as unusually intense and everyday function is affected. A potential mechanism underlying over-responsivity is an imbalance between neural excitation and inhibition in which inhibitory influences are relatively weakened. Therefore, interventions that boost neural inhibition or reduce neural excitation may reduce SOR; Vitamin-B6 is the coenzyme for the conversion of excitatory glutamate to inhibitory gamma-aminobutyric acid (GABA), and in animal models, it both increases the concentration of GABA and reduces glutamate.

AIMS

To discover whether taking a high dose of Vitamin-B6 reduces SOR and other aspects of sensory reactivity.

METHODS

We recruited 300 adults (249 females) from the general population who completed the Sensory Processing 3-Dimensions Scale (SP-3D) first at baseline, and again following randomisation to either 1 month's supplementation with 100 mg Vitamin-B6, or one of two control conditions (1000 µg Vitamin-B12 or placebo). To focus on individuals who experience SOR, we analysed the effects of supplementation only on individuals with high baseline SOR scores (above the 87th percentile).

RESULTS

In individuals with SOR at baseline, Vitamin-B6 selectively reduced SOR compared to both placebo and Vitamin-B12. We also found that Vitamin-B6 selectively reduced postural disorder in individuals with high scores on this subscale at baseline, but there were no effects on the four remaining SP-3D subscales.

CONCLUSIONS

Clinical trials and mechanistic studies should now be conducted in autism, attention deficit hyperactivity disorder and other groups with SOR.

The impact of vitamin E, vitamin B6, and niacin intake on cataract incidence based on NHANES 2005-2008 data

Objective

This investigation aims to elucidate the correlations between dietary intakes of vitamin E, B6, and niacin and the incidence of cataracts, utilizing the comprehensive NHANES 2005-2008 dataset to affirm the prophylactic roles of these nutrients against cataract formation.

Methods

Using data from the NHANES 2005-2008 cycles, this analysis concentrated on 7,247 subjects after exclusion based on incomplete dietary or cataract data. The identification of cataracts was determined through participants' self-reported ophthalmic surgical history. Nutritional intake was gauged using the automated multiple pass method, and the data were analyzed using logistic and quantile regression analyses to investigate the relationship between vitamin consumption and cataract prevalence.

Results

Our analysis identified significant inverse associations between the intake of vitamins E, B6, and niacin and the risk of cataract development. Specifically, higher intakes of vitamin B6 (OR = 0.85, 95% CI = 0.76-0.96, p = 0.0073) and niacin (OR = 0.98, 95% CI = 0.97-1.00, p = 0.0067) in the top quartile were significantly associated with a reduced likelihood of cataract occurrence. Vitamin E intake showed a consistent reduction in cataract risk across different intake levels (OR = 0.96, 95% CI = 0.94-0.99, p = 0.0087), demonstrating a nonlinear inverse correlation.

Conclusion

The outcomes indicate that elevated consumption of vitamin B6 and niacin, in conjunction with regular vitamin E intake, may have the potential to delay or prevent cataract genesis. These results suggest a novel nutritional strategy for cataract prevention and management, advocating that focused nutrient supplementation could be instrumental in preserving eye health and reducing the risk of cataracts. Further research is recommended to validate these findings and establish optimal dosages for maximum benefit.

Extending diagnostic practices in gyrate atrophy: Enzymatic characterization and the development of an in vitro pyridoxine responsiveness assay

Gyrate atrophy of the choroid and retina (GACR) is caused by pathogenic biallelic variants in the gene encoding ornithine-δ-aminotransferase (OAT), and is characterized by progressive vision loss leading to blindness. OAT is a pyridoxal-5'-phosphate (PLP) dependent enzyme that is mainly involved in ornithine catabolism, and patients with a deficiency develop profound hyperornithinemia. Therapy is aimed at lowering ornithine levels through dietary arginine restriction and, in some cases, through enhancement of OAT activity via supraphysiological dosages of pyridoxine. In this study, we aimed to extend diagnostic practices in GACR by extensively characterizing the consequences of pathogenic variants on the enzymatic function of OAT, both at the level of the enzyme itself as well as the flux through the ornithine degradative pathway. In addition, we developed an in vitro pyridoxine responsiveness assay. We identified 14 different pathogenic variants, of which one variant was present in all patients of Dutch ancestry (p.(Gly353Asp)). In most patients the enzymatic activity of OAT as well as the rate of [14C]-ornithine flux was below the limit of quantification (LOQ). Apart from our positive control, only one patient cell line showed responsiveness to pyridoxine in vitro, which is in line with the reported in vivo pyridoxine responsiveness in this patient. None of the patients harboring the p.(Gly353Asp) substitution were responsive to pyridoxine in vivo or in vitro. In silico analysis and small-scale expression experiments showed that this variant causes a folding defect, leading to increased aggregation properties that could not be rescued by PLP. Using these results, we developed a diagnostic pipeline for new patients suspected of having GACR. Adding OAT enzymatic analyses and in vitro pyridoxine responsiveness to diagnostic practices will not only increase knowledge on the consequences of pathogenic variants in OAT, but will also enable expectation management for therapeutic modalities, thus eventually improving clinical care.

A Comparison of the Health Benefits of Customized Multivitamins and Standard Supplementation Post-bariatric Surgery: A Systematic Review

Rates of obesity increase worldwide year after year. This review explored if customized multivitamins (CMV) resulted in less micronutrient deficiency and higher serum levels of vitamins and minerals when compared to standard multivitamins (SMV) post-bariatric surgery in adults. Vitamins investigated were vitamins B1, B6, B12, D, parathyroid hormone (PTH), calcium, iron, hemoglobin, ferritin, folic acid, zinc, and magnesium. In Roux-en-Y gastric bypass (RYGB) patients weight loss surgeries (WLS) Forte or chewable CMV were studied, while in sleeve gastrectomy (SG) patients, WLS Optimum 1.0 (Opt. 1.0) or WLS Optimum 2.0 (Opt. 2.0) multivitamins were studied. An electronic search was performed on three databases (PubMed (n=28), Embase (n=120), and Cochrane (n=106)) to identify clinical trials and cohort studies. The inclusion criteria focused on studies since 2011 for adults ≥18 years old post-GB and SG. The keywords included bypass, sleeve, WLS, and multivitamins. Four clinical trials and three cohort studies were included. Jadad Scale was used to assess the quality and the bias risk in the clinical trials and the Newcastle-Ottawa scale (NOS) was used for the cohort studies. The PICO model and PRISMA rules were followed, where the outcomes targeted certain vitamin serum levels and the levels of deficiencies. The results of WLS Forte were better than SMV. The chewable CMV and Opt. 1.0 results were comparable to SMV. Opt. 2.0 was slightly better than Opt. 1.0. Further modifications would enhance the CMV presented in this systemic review. SMV would still be recommended until CMV are modified and tested. Multi-center trials that monitor the effect of the modified CMV on the serum levels of vitamins and minerals in the longer term in different wider populations are needed.

Impressive clinical improvement and disappearance of neuropathic pain in an adult patient with hypophosphatasia treated with asfotase alfa

Hypophosphatasia (HPP) is a rare disorder, resulting from loss-of-function variants of the ALPL gene encoding non-tissue specific alkaline phosphatase (TNSALP). Presentation varies largely, with increased severity usually occurring with earlier disease onset. Here we describe the clinical improvement of a 57-year-old woman with childhood onset HPP, after initiating treatment with asfotase alfa (Strensiq®). This was started because of the rapid and progressive radiological deterioration of bone structure after placement of nails in both upper legs for spontaneous atypical femur fracture (AFF) - like fractures. Initiation of treatment, not only resulted in stabilization of bone structure on X-rays, but within a few weeks there was a dramatic reduction of burning pain sensations in the lower legs, attributed in retrospect to neuropathic pain, and also almost complete disappearance of headaches. Additionally, unhealed metatarsal fractures finally healed after almost 10 years. Drug efficacy was further evaluated through -quality of life questionnaires and multiple tests conducted by the physiotherapist, and showed clear improvements. Within 3 months after starting asfotase alfa, the patient was able to carry out her daily tasks indoors without relying on a walker and even started electric bike rides for 20 km/day. In conclusion, treatment with asfotase alfa, halted rapid radiological bone deterioration after bilateral intramedullary femoral pen placement and strongly increased quality of life, marked by rapid disappearance of neuropathic pain, reduction in headaches and musculoskeletal pains, and enhanced muscle strength and mobility. The quick and almost complete disappearance of neuropathic pain and headache suggests a relation with disturbed levels of metabolites in HPP.

Impacts of high-dose riboflavin on cytotoxicity, antioxidant, growth, reproductive gene expressions, and genotoxicity in the rainbow trout gonadal cells

Riboflavin (vitamin B2 found in food) is a precursor of flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), which study as coenzymes for a variety of cellular processes including biosynthesis, homocysteine metabolism, detoxification, and various oxidation and reduction reactions. Although studies on the symptoms resulting from riboflavin deficiency are intense, studies on the effects of high doses of riboflavin are almost absent. This report aimed to examine the actions of riboflavin on cell viability, the transcriptional expressions of antioxidant enzyme (gsr and gpx1a), growth (gh1, igf1, and igf2), the reproductive (bol) genes and DNA damage in the rainbow trout gonad cells (RTG-2) for 48 h. All concentrations of riboflavin (3.125, 6.25, 12.5, 25, 50, and 100 μM) significantly reduced the RTG-2 cell viability. Riboflavin (LD50: 12.5 μM) significantly downregulated the transcriptional expressions of gpx1a, igf1, and bol genes, while it non-significantly upregulated or downregulated the transcriptional expression of gsr, igf2, and gh1 genes in the RTG-2 cells in comparison to the control group for 48 h. The comet assay demonstrated that riboflavin significantly raised tail DNA% >10% DMSO (positive control). Based on the outcomes, high doses of riboflavin exhibit the potential to have a role in cellular mechanisms, including especially reproduction, DNA damage, and cell death.

Pyridoxamine Attenuates Doxorubicin-Induced Cardiomyopathy without Affecting Its Antitumor Effect on Rat Mammary Tumor Cells

Doxorubicin (DOX) is commonly used in cancer treatment but associated with cardiotoxicity. Pyridoxamine (PM), a vitamin B6 derivative, could be a cardioprotectant. This study investigated the effect of PM on DOX cardiotoxicity and DOX antitumor effectiveness. Sprague Dawley rats were treated intravenously with DOX (2 mg/kg/week) or saline over eight weeks. Two other groups received PM via oral intake (1 g/L in water bottles) next to DOX or saline. Echocardiography was performed after eight weeks. PM treatment significantly attenuated the DOX-induced reduction in left ventricular ejection fraction (72 ± 2% vs. 58 ± 3% in DOX; p < 0.001) and increase in left ventricular end-systolic volume (0.24 ± 0.02 µL/cm2 vs. 0.38 ± 0.03 µL/cm2 in DOX; p < 0.0001). Additionally, LA7 tumor cells were exposed to DOX, PM, or DOX and PM for 24 h, 48 h, and 72 h. Cell viability, proliferation, cytotoxicity, and apoptosis were assessed. DOX significantly reduced LA7 cell viability and proliferation (p < 0.0001) and increased cytotoxicity (p < 0.05) and cleaved caspase-3 (p < 0.001). Concomitant PM treatment did not alter the DOX effect on LA7 cells. In conclusion, PM attenuated DOX-induced cardiomyopathy in vivo without affecting the antitumor effect of DOX in vitro, highlighting PM as a promising cardioprotectant for DOX-induced cardiotoxicity.

Exploring health and toxicity in food choices: 10 examples navigating the gray area

People's perception on what is healthy and what is toxic food, determines food preferences and eating behavior. The difference between heathy and toxic food and food ingredients is however not always clear. This is illustrated with 10 examples. Unjustly, all-natural food is regarded as safe. Regulation on health claims on food and food risks is not balanced. Biphasic responses of the physiological effect of food ingredients show that mild toxicity of these substances results in health promotion. Nutritional substances with drugs may have either a negative or a positive effect on health. New toxicological methodologies can be brought into play, to better understand the dynamics of health and disease. Unfortunately, we still cannot taste toxicity.

B Vitamins, Glucoronolactone and the Immune System: Bioavailability, Doses and Efficiency

The present review deals with two main ingredients of energy/power drinks: B vitamins and glucuronolactone and their possible effect on the immune system. There is a strong relationship between the recommended daily dose of selected B vitamins and a functional immune system. Regarding specific B vitamins: (1) Riboflavin is necessary for the optimization of reactive oxygen species (ROS) in the fight against bacterial infections caused by Staphylococcus aureus and Listeria monocytogenes. (2) Niacin administered within normal doses to obese rats can change the phenotype of skeletal fibers, and thereby affect muscle metabolism. This metabolic phenotype induced by niacin treatment is also confirmed by stimulation of the expression of genes involved in the metabolism of free fatty acids (FFAs) and oxidative phosphorylation at this level. (3) Vitamin B5 effects depend primarily on the dose, thus large doses can cause diarrhea or functional disorders of the digestive tract whereas normal levels are effective in wound healing, liver detoxification, and joint health support. (4) High vitamin B6 concentrations (>2000 mg per day) have been shown to exert a significant negative impact on the dorsal root ganglia. Whereas, at doses of approximately 70 ng/mL, sensory symptoms were reported in 80% of cases. (5) Chronic increases in vitamin B12 have been associated with the increased incidence of solid cancers. Additionally, glucuronolactone, whose effects are not well known, represents a controversial compound. (6) Supplementing with D-glucarates, such as glucuronolactone, may help the body's natural defense system function better to inhibit different tumor promoters and carcinogens and their consequences. Cumulatively, the present review aims to evaluate the relationship between the selected B vitamins group, glucuronolactone, and the immune system and their associations to bioavailability, doses, and efficiency.

Nutritional peripheral neuropathies

Nutritional peripheral neuropathies are a global problem, heavily influenced by geopolitical, cultural and socioeconomic factors. Peripheral neuropathy occurs most frequently secondary to B-vitamin deficiencies, which is suspected to increase in years to come due to the popularity of vegan and vegetarian diets and increased use of bariatric surgery.This review will focus on the common B-vitamins for which a causal link to peripheral neuropathy is more established (vitamins B1, B2, B6, B9 and B12). We will review the historical human and animal data on which much of the clinical descriptions of vitamin deficiencies are based and summarise current available tools for accurately diagnosing a nutritional deficiency. We will also review recently described genetic diseases due to pathogenic variants in genes involved in B-vitamin metabolism that have helped to inform the phenotypes and potential causality of certain B-vitamins in peripheral neuropathy (B2 and B9).Endemic outbreaks of peripheral neuropathy over the last two centuries have been linked to food shortages and nutritional deficiency. These include outbreaks in Jamaican sugar plantation workers in the nineteenth century (Strachan's syndrome), World War two prisoners of war, Cuban endemic neuropathy and also Tanzanian endemic optic neuropathy, which remains a significant public health burden today. An improved understanding of lack of which vitamins cause peripheral neuropathy and how to identify specific deficiencies may lead to prevention of significant and irreversible disability in vulnerable populations.

Vitamin B6 Toxicity Secondary to Daily Multivitamin Use: A Case Report

Vitamin B6 is a water-soluble vitamin that is an important cofactor in various metabolic processes. Although rare, its consumption can sometimes result in toxicity, which typically presents with peripheral neuropathy in the early stage. While vitamin B6 toxicity is most often associated with supplemental mega-doses of more than 50 mg/day, more recent studies have shown that toxicity can occur in cases of much smaller doses as well. We present a case of a 73-year-old male with a three-year history of progressive peripheral neuropathy who was found to have a serum vitamin B6 level of 259.9 nmol/L (reference range: 20-125 nmol/L) but only reported taking a daily multivitamin containing 6 mg of vitamin B6. This case of toxicity in the setting of a daily intake lower than the European Food Safety Administration's (EFSA) newly established Tolerable Upper Intake Level (UL) of 12 mg/day highlights the need for further research into the effects of relatively low-dose vitamin B6 supplementation.

Effect of pyridoxine or cobalamin supplementation on apoptosis and cell cycle progression in a human glioblastoma cell line

Glioblastoma is the most aggressive type of brain tumor, with current therapies failing to significantly improve patient survival. Vitamins have important effects on cellular processes that are relevant for tumor development and progression.

AIM

The present study explored the effect of pyridoxine or cobalamin supplementation on the viability and cell cycle progression of human glioblastoma cell line U-87 MG.

METHOD

Cell cultures were treated with increasing concentrations of pyridoxine or cobalamin for 24-72 h. After supplementation, cell viability and cell cycle progression were assessed by spectrophotometry and flow cytometry. Analysis of Bcl-2 and active caspase 3 expression in supplemented cells was performed by western blot.

RESULT

The results show that pyridoxine supplementation decreases cell viability in a dose and time dependent manner. Loss of viability in pyridoxin-supplemented cells is probably related to less cell cycle progression, higher active caspase 3 expression and apoptosis. In addition, Bcl-2 expression did not appear to be altered by vitamin supplementation, but active caspase 3 expression was significantly increased in pyridoxine-, but not cobalamin-supplemented cells, furthermore, cobalamin inhibited the pyridoxine cytotoxicity in the cell viability assay when combined.

CONCLUSION

The results suggest that pyridoxine supplementation promotes apoptosis in human glioblastoma-derived cells and may be useful to enhance the effect of cytotoxic therapies in vivo.

Identifying risk factors for adverse events of pyridoxal phosphate in infantile epileptic spasms syndrome

INTRODUCTION

Infantile epileptic spasms syndrome (IESS) is characterized by epileptic spasms, regardless of hypsarrhythmia on electroencephalogram or neurodevelopmental delay. In Japan, pyridoxal 5'-phosphate (PLP) is often used as the first-line treatment for IESS because it is effective in a certain number of patients. Although several studies have reported serious adverse events following PLP treatment, no study has investigated the risk factors for such occurrences.

OBJECTIVE

To investigate adverse events associated with PLP therapy for the treatment of IESS and to identify the associated risk factors.

MATERIALS AND METHODS

We retrospectively evaluated adverse events in 59 patients with IESS at Tottori University Hospital between January 1995 and September 2022. We subsequently collected and analyzed their clinical data and analyzed the risk factors associated with each adverse event. The cutoff values and relative risk (RR) were analyzed for items with significant associations with adverse events.

RESULTS

Twenty-seven (51.9%) participants experienced adverse events, including vomiting in 16 participants (59.3%), elevated liver enzyme levels in 15 participants (55.6%), and rhabdomyolysis in two participants (3.4%). No significant differences were observed between the non-adverse events group and the overall adverse events group, as well as between the non-adverse events group and the vomiting group, in terms of the factors examined. However, when comparing the non-adverse events group with the group with elevated liver enzyme levels, age at PLP treatment showed a negative correlation, whereas PLP dose showed a positive correlation with elevated liver enzyme levels. The cutoff dose was 40 mg/kg/day (73.3% sensitivity and 60.7% specificity), and the cutoff age was 9 months (100% sensitivity and 40.0% specificity). RRs of doses ≥40 mg/kg/day and age <9 months were 2.6 and 3.6, respectively.

CONCLUSIONS

Adverse events of PLP therapy, including vomiting, elevated liver enzymes, and rhabdomyolysis, were observed in approximately half of the participants. Age under 9 months and a dose ≥40 mg/kg/day were identified as risk factors for elevation of liver enzymes on PLP treatment in infants with IESS, with rhabdomyolysis can occur in the younger or higher dose cases.

Diet and ideal food pyramid to prevent or support the treatment of diabetic retinopathy, age-related macular degeneration, and cataracts

Many eye diseases, such as diabetic retinopathy (DR), age-related macular degeneration (AMD), and cataracts are preventable and treatable with lifestyle. The objective of this review is to assess the most recent research on the ideal dietary approach to prevent or support the treatment of DR, AMD, and cataracts, as well as to construct a food pyramid that makes it simple for people who are at risk of developing these pathologies to decide what to eat. The food pyramid presented here proposes what should be consumed every day: 3 portions of low glycemic index (GI) grains (for fiber and zinc content), 5 portions (each portion: ≥200 g/day) of fruits and vegetables (spinach, broccoli, zucchini cooked, green leafy vegetables, orange, kiwi, grapefruit for folic acid, vitamin C, and lutein/zeaxanthin content, at least ≥42 μg/day, are to be preferred), extra virgin olive (EVO) oil (almost 20 mg/day for vitamin E and polyphenols content), nuts or oil seeds (20-30 g/day, for zinc content, at least ≥15.8 mg/day); weekly: fish (4 portions, for omega-3 content and eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) 0.35-1.4 g/day), white meat (3 portions for vitamin B12 content), legumes (2 portions for vegetal proteins), eggs (2 portions for lutein/zeaxanthin content), light cheeses (2 portions for vitamin B6 content), and almost 3-4 times/week microgreen and spices (saffron and curcumin). At the top of the pyramid, there are two pennants: one green, which indicates the need for personalized supplementation (if daily requirements cannot be met through diet, omega-3, and L-methylfolate supplementation), and one red, which indicates that certain foods are prohibited (salt and sugar). Finally, 3-4 times per week, 30-40 min of aerobic and resistance exercises are required.

Scientific opinion on the tolerable upper intake level for vitamin B6

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on the tolerable upper intake level (UL) for vitamin B6. Systematic reviews of the literature were conducted by a contractor. The relationship between excess vitamin B6 intakes and the development of peripheral neuropathy is well established and is the critical effect on which the UL is based. A lowest-observed-effect-level (LOAEL) could not be established based on human data. A reference point (RP) of 50 mg/day is identified by the Panel from a case-control study, supported by data from case reports and vigilance data. An uncertainty factor (UF) of 4 is applied to the RP to account for the inverse relationship between dose and time to onset of symptoms and the limited data available. The latter covers uncertainties as to the level of intake that would represent a LOAEL. This leads to a UL of 12.5 mg/day. From a subchronic study in Beagle dogs, a LOAEL of 50 mg/kg body weight (bw) per day can be identified. Using an UF of 300, and a default bw of 70 kg, a UL of 11.7 mg/day can be calculated. From the midpoint of the range of these two ULs and rounding down, a UL of 12 mg/day is established by the Panel for vitamin B6 for adults (including pregnant and lactating women). ULs for infants and children are derived from the UL for adults using allometric scaling: 2.2-2.5 mg/day (4-11 months), 3.2-4.5 mg/day (1-6 years), 6.1-10.7 mg/day (7-17 years). Based on available intake data, EU populations are unlikely to exceed ULs, except for regular users of food supplements containing high doses of vitamin B6.

Electrochemical preparation and the characterizations of poly(3,5-diamino 1,2,4-triazole) film for the selective determination of pyridoxine in pharmaceutical formulations

This work describes the synthesis and characterization of a polymeric film of 3,5-diamino 1,2,4-triazole on a pencil graphite electrode for the selective sensing of pyridoxine (PY). The PGE was modified using the electropolymerization process by the potentiodynamic method. The polymerized electrode (PDAT/PGE) was characterized by IR, SEM, AFM, cyclic voltammetry, and electrochemical impedance spectroscopy. PY undergoes irreversible oxidation at 0.79 V on PDAT/PGE in phosphate buffer of pH 5. Using the differential pulse voltammetric technique (DPV), PY showed a linear range from 5 to 950 μM with a lower detection limit of 2.96 μM. The PDAT/PGE was applied for the analytical determination of PY in pharmaceutical tablets with good recovery.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s11696-023-02777-5.

The Rationale for Vitamin, Mineral, and Cofactor Treatment in the Precision Medical Care of Autism Spectrum Disorder

Children with autism spectrum disorder may exhibit nutritional deficiencies due to reduced intake, genetic variants, autoantibodies interfering with vitamin transport, and the accumulation of toxic compounds that consume vitamins. Importantly, vitamins and metal ions are essential for several metabolic pathways and for neurotransmitter functioning. The therapeutic benefits of supplementing vitamins, minerals (Zinc, Magnesium, Molybdenum, and Selenium), and other cofactors (coenzyme Q10, alpha-lipoic acid, and tetrahydrobiopterin) are mediated through their cofactor as well as non-cofactor functions. Interestingly, some vitamins can be safely administered at levels far above the dose typically used to correct the deficiency and exert effects beyond their functional role as enzyme cofactors. Moreover, the interrelationships between these nutrients can be leveraged to obtain synergistic effects using combinations. The present review discusses the current evidence for using vitamins, minerals, and cofactors in autism spectrum disorder, the rationale behind their use, and the prospects for future use.

Pyridoxamine reduces methylglyoxal and markers of glycation and endothelial dysfunction, but does not improve insulin sensitivity or vascular function in abdominally obese individuals: A randomized double-blind placebo-controlled trial

AIM

To investigate the effects of pyridoxamine (PM), a B6 vitamer and dicarbonyl scavenger, on glycation and a large panel of metabolic and vascular measurements in a randomized double-blind placebo-controlled trial in abdominally obese individuals.

MATERIALS AND METHODS

Individuals (54% female; mean age 50 years; mean body mass index 32 kg/m² ) were randomized to an 8-week intervention with either placebo (n = 36), 25 mg PM (n = 36) or 200 mg PM (n = 36). We assessed insulin sensitivity, β-cell function, insulin-mediated microvascular recruitment, skin microvascular function, flow-mediated dilation, and plasma inflammation and endothelial function markers. PM metabolites, dicarbonyls and advanced glycation endproducts (AGEs) were measured using ultra-performance liquid chromatography tandem mass spectrometry. Treatment effects were evaluated by one-way ANCOVA.

RESULTS

In the high PM dose group, we found a reduction of plasma methylglyoxal (MGO) and protein-bound Nδ-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1), as compared to placebo. We found a reduction of the endothelial dysfunction marker soluble vascular cell adhesion molecule-1 (sVCAM-1) in the low and high PM dose group and of soluble intercellular adhesion molecule-1 (sICAM-1) in the high PM dose, as compared to placebo. We found no treatment effects on insulin sensitivity, vascular function or other functional outcome measurements.

CONCLUSIONS

This study shows that PM is metabolically active and reduces MGO, AGEs, sVCAM-1 and sICAM-1, but does not affect insulin sensitivity and vascular function in abdominally obese individuals. The reduction in adhesion markers is promising because these are important in the pathogenesis of endothelial damage and atherosclerosis.

Vitamin B6 Neonatal Toxicity

Vitamin B6 is a micronutrient required by the body. It acts as a coenzyme in biochemical reactions. Vitamin B6 toxicity is not caused by the intake of food-based sources. The few reported cases of vitamin B6 toxicity are always caused by overdosing of nutritional supplements. Chronic toxicity typically occurs with peripheral neuropathy such as paraesthesia, ataxia, and imbalance, paradoxically mimicking vitamin B6 deficiency. However, the prognosis is favorable, and symptoms usually show improvement once excessive vitamin B6 levels return to the physiological range. We report a newborn presenting with diffuse tremor at birth, interpreted as secondary to the mother's intake of high doses of a supplement containing vitamin B6 during pregnancy and breastfeeding. As expected, the newborn's serum levels of vitamin B6 were high. The tremors disappeared when the maternal supplement was stopped.

Preventing Vitamin B6-Related Neurotoxicity

BACKGROUND

Vitamin B6 is essential for life and plays a critical role in many biochemical and physiological processes in the human body. The term B6 collectively refers to 6 water-soluble vitamers, and only the pyridoxal 5'-phosphate (PLP) serves as the biologically active form. A plasma PLP concentration above 30 nmol/L (7.4 μg/L) is indicative of an adequate vitamin B6 status for all age and sex groups. The currently recommended daily allowance of B6 (1.5-2 mg/d) from dietary sources frequently results in inadequate B6 status (<20 nmol/L or 5 μg/L) in many elderly patients and patients with comorbid conditions. PLP-based supplements are preferred and should be administered weekly in low doses (50-100 mg) to maintain a stable serum PLP level between 30 and 60 nmol/L or 7.4 and 15 μg/L.

AREAS OF UNCERTAINTY

It is challenging for physicians to prescribe a safe dose of B6 supplements because of the narrow therapeutic index. The association between elevated levels of pyridoxine and neuropathy is not well established. PLP-based supplements are shown to be least neurotoxic, but further clinical trials are needed to establish the long-term safety in high doses.

DATA SOURCES

PubMed search of randomized control trials and meta-analyses.

THERAPEUTIC OPINION

Plasma B6 levels should be ordered as a part of workup of any unexplained anemia before labeling as "anemia of chronic disease." B6 supplementation is also crucial in the management of chronic Mg deficiency resistant to therapy. When B6 is administered daily in supraphysiologic doses, there is a potential for the development of neurotoxicity (typically at levels >100 nmol/L or 25 μg/L). PLP-based supplements are preferred over pyridoxine supplements because of minimal neurotoxicity observed in neuronal cell viability tests. Since B6 metabolites have a long half-life, weekly administration is preferred over daily use to prevent toxicity.

Effects of Combining Biofactors on Bioenergetic Parameters, Aβ Levels and Survival in Alzheimer Model Organisms

Increased amyloid beta (Aβ) levels and mitochondrial dysfunction (MD) in the human brain characterize Alzheimer disease (AD). Folic acid, magnesium and vitamin B6 are essential micro-nutrients that may provide neuroprotection. Bioenergetic parameters and amyloid precursor protein (APP) processing products were investigated in vitro in human neuroblastoma SH-SY5Y-APP695 cells, expressing neuronal APP, and in vivo, in the invertebrate Caenorhabditis elegans (CL2006 & GMC101) expressing muscular APP. Model organisms were incubated with either folic acid and magnesium-orotate (ID63) or folic acid, magnesium-orotate and vitamin B6 (ID64) in different concentrations. ID63 and ID64 reduced Aβ, soluble alpha APP (sAPPα), and lactate levels in SH-SY5Y-APP695 cells. The latter might be explained by enhanced expression of lactate dehydrogenase (LDHA). Micronutrient combinations had no effects on mitochondrial parameters in SH-SY5Y-APP695 cells. ID64 showed a significant life-prolonging effect in C. elegans CL2006. Incubation of GMC101 with ID63 significantly lowered Aβ aggregation. Both combinations significantly reduced paralysis and thus improved the phenotype in GMC101. Thus, the combinations of the tested biofactors are effective in pre-clinical models of AD by interfering with Aβ related pathways and glycolysis.

B vitamin supply in plants and humans: the importance of vitamer homeostasis

B vitamins are a group of water-soluble micronutrients that are required in all life forms. With the lack of biosynthetic pathways, humans depend on dietary uptake of these compounds, either directly or indirectly, from plant sources. B vitamins are frequently given little consideration beyond their role as enzyme accessory factors and are assumed not to limit metabolism. However, it should be recognized that each individual B vitamin is a family of compounds (vitamers), the regulation of which has dedicated pathways. Moreover, it is becoming increasingly evident that individual family members have physiological relevance and should not be sidelined. Here, we elaborate on the known forms of vitamins B₁ , B₆ and B₉ , their distinct functions and importance to metabolism, in both human and plant health, and highlight the relevance of vitamer homeostasis. Research on B vitamin metabolism over the past several years indicates that not only the total level of vitamins but also the oft-neglected homeostasis of the various vitamers of each B vitamin is essential to human and plant health. We briefly discuss the potential of plant biology studies in supporting human health regarding these B vitamins as essential micronutrients. Based on the findings of the past few years we conclude that research should focus on the significance of vitamer homeostasis - at the organ, tissue and subcellular levels - which could improve the health of not only humans but also plants, benefiting from cross-disciplinary approaches and novel technologies.

Pyridoxamine and Aminoguanidine Attenuate the Abnormal Aggregation of β-Tubulin and Suppression of Neurite Outgrowth by Glyceraldehyde-Derived Toxic Advanced Glycation End-Products

Diabetes mellitus (DM) has been identified as a risk factor for the onset and progression of Alzheimer’s disease (AD). In our previous study, we demonstrated that glyceraldehyde (GA)-derived toxic advanced glycation end-products (toxic AGEs, TAGE) induced similar alterations to those observed in AD. GA induced dysfunctional neurite outgrowth via TAGE-β-tubulin aggregation, which resulted in the TAGE-dependent abnormal aggregation of β-tubulin and tau phosphorylation in human neuroblastoma SH-SY5Y cells. However, the effects of inhibitors of AGE formation on dysfunctional neurite outgrowth caused by GA-induced abnormalities in the aggregation of β-tubulin and tau phosphorylation remain unknown. Aminoguanidine (AG), an AGE inhibitor, and pyridoxamine (PM), a natural form of vitamin B₆ (VB₆), are effective AGE inhibitors. Therefore, the present study investigated whether AG or PM ameliorate TAGE-β-tubulin aggregation and the suppression of neurite outgrowth by GA. The results obtained showed that AG and PM inhibited the formation of TAGE-β-tubulin, mitigated the GA-induced suppression of neurite outgrowth, and reduced GA-mediated increases in tau phosphorylation levels. Collectively, these results suggest the potential of AG and PM to prevent the DM-associated onset and progression of AD.

Recent Advances in Water-Soluble Vitamins Delivery Systems Prepared by Mechanical Processes (Electrospinning and Spray-Drying Techniques) for Food and Nutraceuticals Applications-A Review

Water-soluble vitamins are essential micronutrients in diets and crucial to biochemical functions in human body physiology. These vitamins are essential for healthy diets and have a preventive role against diseases. However, their limitations associated with high sensitivity against external conditions (temperature, light, pH, moisture, oxygen) can lead to degradation during processing and storage. In this context, microencapsulation may overcome these conditions, protecting a biomolecule’s bioavailability, stability, and effectiveness of delivery. This technique has been used to produce delivery systems based on polymeric agents that surround the active compounds. The present review focuses on the most relevant topics of water-soluble vitamin encapsulation using promising methods to produce delivery vehicles—electrohydrodynamic (electrospinning and electrospraying) and spray-drying techniques. An overview of the suitable structures produced by these processes is provided. The review introduces the general principles of the methods, advantages, disadvantages, and involved parameters. A brief list of the used physicochemical techniques for the systems’ characterization is discussed in this review. Electrospinning and spray-drying techniques are the focus of this investigation in order to guarantee vitamins’ bioaccessibility and bioavailability. Recent studies and the main encapsulating agents used for these micronutrients in both processes applied to functional food and nutraceutical areas are highlighted in this review.

Comparison of Herbal Medicines Used for Women's Menstruation Diseases in Different Areas of the World

Aims: This review aims to compare the use of herbal medicine used to treat women's menstruation and the prevalence of menstrual diseases in different regions, which reveal the use of herbal medicine globally and provide scientific guidance for improving women's health. Materials and Methods: The information available on herbal medicines for women between the years 2000 and 2021 was systematically collected via the library and electronic search systems such as Google Scholar, PubMed, ScienceDirect, and Web of Science as well as secondary resources including books and conference proceedings. Results: Totally, 571 ethnic medicines commonly used for women's menstruation health in Asia, Europe, Oceania, Africa, and America were accounted. Zingiber officinale Roscoe (Ginger), Ruta graveolens L. (Common rue), Angelica sinensis (Oliv.) Diels (Angelica sinensis), Foeniculum vulgare Mill (Fennel), Catharanthus roseus (L.) G. Don (Catharanthus roseus) and other medicines which have obvious advantages and long-term usage are utilized in the treatment of menstrual diseases. Family Asteraceae, Lamiaceae, Apiaceae, Fabaceae, and Zingiberaceae are the most common medicinal plant families used for such treatments. In many instances, the application of fresh parts of plants was observed because of the healers' belief regarding the higher efficiency of the medicine made from fresh plants. Edible plants are used in a wide range of countries. Conclusion: Women's menstruation health is directly related to their health condition. Traditional medicines of most ethnic groups have contributed to women's health care and treatment of gynecological diseases. Practitioners in this field have gained elaborate experience in treatments and medication, and assembled a large number of effective drugs and prescriptions. These experiences have also been inherited and developed by modern clinical application and scientific research. However, the basic research on these drugs is not sufficient, the knowledge of drug use has not been fully popularized, the advantages of drugs have not been fully utilized, and the guiding potential to modern drug research continues to be insufficient. As such, it is necessary to further promote and make a significant contribution to women's health.

Hypophosphatasia: Vitamin B6 status of affected children and adults

Hypophosphatasia (HPP) is the heritable dento-osseous disease caused by loss-of-function mutation(s) of the gene ALPL that encodes the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP). TNSALP is a cell-surface homodimeric phosphomonoester phosphohydrolase expressed in healthy people especially in the skeleton, liver, kidneys, and developing teeth. In HPP, diminished TNSALP activity leads to extracellular accumulation of its natural substrates including inorganic pyrophosphate (PPi), an inhibitor of mineralization, and pyridoxal 5'-phosphate (PLP), the principal circulating form of vitamin B₆ (B₆). Autosomal dominant and autosomal recessive inheritance involving >450 usually missense defects scattered throughout ALPL largely explains the remarkably broad-ranging severity of this inborn-error-of-metabolism. In 1985 when we identified elevated plasma PLP as a biochemical hallmark of HPP, all 14 investigated affected children and adults had markedly increased PLP levels. However, pyridoxal (PL), the dephosphorylated form of PLP that enters cells to cofactor many enzymatic reactions, was not low but often inexplicably elevated. Levels of pyridoxic acid (PA), the B₆ degradation product quantified to assess B₆ sufficiency, were unremarkable. Canonical signs or symptoms of B₆ deficiency or toxicity were absent. B₆-dependent seizures in infants with life-threatening HPP were later explained by their profound deficiency of TNSALP activity blocking PLP dephosphorylation to PL and diminishing gamma-aminobutyric acid synthesis in the brain. Now, there is speculation that altered B₆ metabolism causes further clinical complications in HPP. Herein, we assessed the plasma PL and PA levels accompanying previously reported elevated plasma PLP concentrations in 150 children and adolescents with HPP. Their mean (SD) plasma PL level was nearly double the mean for our healthy pediatric controls: 66.7 (59.0) nM versus 37.1 (22.2) nM (P < 0.0001), respectively. Their PA levels were broader than our pediatric control range, but their mean value was normal; 40.2 (25.1) nM versus 39.3 (9.9) nM (P = 0.7793), respectively. In contrast, adults with HPP often had plasma PL and PA levels suggestive of dietary B₆ insufficiency. We discuss why the B₆ levels of our pediatric patients with HPP would not cause B₆ toxicity or deficiency, whereas in affected adults dietary B₆ insufficiency can develop.

Chitosan crosslinking with pyridoxal 5-phosphate vitamer toward biocompatible hydrogels for in vivo applications

Vitamin B6 is an essential micronutrient in the mammalian diet, with role of coenzyme and synergistic effect with some antibiotics and antitumor drugs. Based on these, we hypothesized that its use for the preparation of hydrogels can yield multifunctional biomaterials suitable for in vivo applications. To this aim, chitosan was reacted with the active form of vitamin B6, pyridoxal 5-phosphate, via acid condensation, when clear hydrogels were obtained. Their investigation by structural characterization methods proved that the hydrogelation was a consequence of both covalent imine formation and physical interactions. The novel hydrogels had microporous morphology and showed shrinking effect in phosphate buffer, indicating good shape preservation and slow dissolution in in vivo environment. Their enzymatic biodegradation could be controlled by the imination degree, varying from 40 to 61% in 21 days. They demonstrated very good in vitro cytocompatibility on normal human dermal fibroblasts cells and no harmful effect on experimental mice, confirming their safely use for in vivo application.

In vivo toxicity assessment of 4'-O-methylpyridoxine from Ginkgo biloba seeds: Growth, hematology, metabolism, and oxidative parameters

4'-O-methylpyridoxine (MPN), a recognized antivitamin B₆ compound, is a potentially poisonous substance found in Ginkgo biloba seeds and leaves. In this work, the body weights, histopathological changes, plasma vitamin B₆ (VB₆), biochemical parameters, oxidative stress responses, and amino acids of rats were investigated after intragastric administration of MPN for 15 days. Results showed that intragastric administration of 50 mg/kg BW MPN caused pathological changes in the brain and heart tissues of rats. Administration of 10 mg/kg and 30 mg/kg BW MPN can significantly increase VB₆ analogs in the plasma of rats, such as pyridoxal-5'-phosphate, pyridoxal. Results of biochemical parameters indicated that MPN can damage brains and hearts by changing the enzyme activity of these organs. These results suggest that consumption of Ginkgo biloba seeds for the long term, even in a small quantity, may lead to poisoning.

Regular intake of energy drinks and multivitamin supplements is associated with elevated plasma vitamin B6 levels in post-bariatric patients

The aim of the present survey was to analyze plasma vitamin B6 levels in post-bariatric patients and to elucidate the causal factors associated with elevated plasma vitamin B6 levels. This is a retrospective analysis of electronic patient data of all post-bariatric patients evaluated at the endocrine outpatient clinic of the University Hospital Basel in 2017, for which plasma vitamin B6 values were assessed during regular follow-up visits. In total, 205 patients were included in the study, whereof a minority of 43% had vitamin B6 levels in the normal range. 50% of the patients had vitamin B6 levels up to fourfold higher than the upper normal limit and 7% had levels more than fourfold above the upper normal limit. Vitamin B6 deficiency was not observed in any patient. While multivitamin supplementation in general was associated with elevated plasma vitamin B6 levels, the highest vitamin B6 levels were found after biliopancreatic diversion (BPD) and in patients who reported daily energy drink intake. Elevated plasma vitamin B6 levels up to fourfold above the upper normal limit are common in postbariatric patients and are associated with regular multivitamin supplementation, while highly elevated plasma vitamin B6 levels were seen primarily upon regular energy drink intake. Thus, a regular follow-up of vitamin B6 plasma levels and critical evaluation of vitamin B6 supplementation, either as part of the multivitamin preparation or related to regular energy drink intake, is highly warranted and should be an integral part of the routine post-bariatric follow-up.

Effects of Acute Beta-Alanine Ingestion and Immersion-Plus-Exercise on Connectedness to Nature and Perceived Pain

This double-blinded, placebo-controlled, crossover study examined the effect of induced painful sensation (via acute Beta Alanine (B-ALA) ingestion) on Love and Care of Nature (LCN), heart rate (HR), rating of perceived exertion (RPE), and McGill Pain Questionnaire (MPQ) during outdoor exercise. Twenty participants volunteered on consecutive days to complete a 0.8 km (0.5 mi) up-hill hike after consuming either B-ALA (6.4 g) or placebo. Immediately after consumption participants answered LCN, RPE, and MPQ questionnaires, immersed in a natural environment for 45 min, and then completed a hike as quickly as possible without running. No difference in HR (p = 0.846), or RPE (p = 0.606) were observed between treatments. Total MPQ scores increased with consumption of B-ALA (p = 0.001). An increased LCN score was observed following exercise regardless of condition (p = 0.035). The results demonstrate that acute B-ALA supplementation is effective in increasing perceived pain sensations. The results also demonstrate an increase in LCN in the presence of increased perceptions of pain sensations during exercise.

[MDR tuberculosis, Alpha-1-anti-trypsin Deficiency, Cough in a Geriatric Nurse]

Multidrug-resistant tuberculosis (MDR-TB) is of low proportion in comparison to the total number of TB patients, however, due to the necessity of a complex medication with potentially severe and life threatening adverse reactions, long term sequelae, and unfavorable outcome special attention is essential. We report the case of a 30-year-old geriatric nurse with a history of chronic cough and hereditary alpha-1-anti-trypsin deficiency (AATD), who suffered from MDR-TB and experienced a number of severe adverse reactions.

Cognitive and neurological outcome of patients in the Dutch pyridoxine-dependent epilepsy (PDE-ALDH7A1) cohort, a cross-sectional study

BACKGROUND

Pyridoxine monotherapy in PDE-ALDH7A1 often results in adequate seizure control, but neurodevelopmental outcome varies. Detailed long-term neurological outcome is unknown. Here we present the cognitive and neurological features of the Dutch PDE-ALDH7A1 cohort.

METHODS

Neurological outcome was assessed in 24 patients (age 1-26 years); classified as normal, complex minor neurological dysfunction (complex MND) or abnormal. Intelligence quotient (IQ) was derived from standardized IQ tests with five severity levels of intellectual disability (ID). MRI's and treatments were assessed.

RESULTS

Ten patients (42%) showed unremarkable neurological examination, 11 (46%) complex MND, and 3 (12%) cerebral palsy (CP). Minor coordination problems were identified in 17 (71%), fine motor disability in 11 (46%), posture/muscle tone deviancies in 11 (46%) and abnormal reflexes in 8 (33%). Six patients (25%) had an IQ > 85, 7 (29%) borderline, 7 (29%) mild, 3 (13%) moderate, and 1 severe ID. Cerebral ventriculomegaly on MRI was progressive in 11. Three patients showed normal neurologic exam, IQ, and MRI. Eleven patients were treated with pyridoxine only and 13 by additional lysine reduction therapy (LRT). LRT started at age <3 years demonstrated beneficial effect on IQ results in 3 patients.

DISCUSSION

Complex MND and CP occurred more frequently in PDE-ALDH7A1 (46% and 12%) than in general population (7% and 0.2%, Peters et al., 2011, Schaefer et al., 2008). Twenty-five percent had a normal IQ. Although LRT shows potential to improve outcomes, data are heterogeneous in small patient numbers. More research with longer follow-up via the International PDE Registry (www.pdeonline.org) is needed.

Quantification of the B6 vitamers in human plasma and urine in a study with pyridoxamine as an oral supplement; pyridoxamine as an alternative for pyridoxine

BACKGROUND AND AIMS

Vitamin B6 is involved in a large spectrum of physiological processes and comprises of the vitamers pyridoxamine (PM), pyridoxal (PL), pyridoxine (PN), and their phosphorylated derivatives including the biological active pyridoxal 5'-phosphate (PLP). While PN toxicity is known to complicate several treatments, PM has shown promise in relation to the treatment of metabolic and age-related diseases by blocking oxidative degradation and scavenging toxic dicarbonyl compounds and reactive oxygen species. We aimed to assess the metabolization of oral PM supplements in a single and three daily dose.

MATERIALS AND METHODS

We optimized and validated a method for the quantification of the B6 vitamers in plasma and urine using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Five healthy volunteers were recruited to study PM metabolization after a single oral dose of 200 mg PM or a three daily dose of 67 mg PM. A third protocol was implemented as control for dietary intake. Venous blood samples, 24 h urine and fasted second void urine samples were collected.

RESULTS

After a single oral dose of 200 mg PM, plasma PM increased in the first 3 h to a maximum of 2324 ± 266 nmol/L. While plasma PM levels returned to baseline after ~10 h of PM intake, PLP increased to a maximum of 2787 ± 329 nmol/L and reached a plateau. We found a small increase of PN to a maximum of 13.5 ± 2.1 nmol/L; it was nearly undetectable after ~12 h. With a three daily dose of 67 mg PM we observed an increase and decline of plasma PM, PL, and PN concentrations after each PM intake. PLP showed a similar increase as in the single dose protocol and accumulated over time.

CONCLUSION

In this study we showed high plasma levels of PM after oral PM supplementation. We found steadily increasing levels of the biologically active PLP, with minimal formation of PN. The B6 vitamer PM is an interesting supplement as an inhibitor of harmful processes in metabolic diseases and for the treatment of vitamin B6 deficiency.

CLINICAL TRIAL REGISTRY

The study was approved by the Medical Ethics Committee of Maastricht University (NL) and was registered at ClinicalTrials.gov as NCT02954588.

Vitamin B-6-Induced Neuropathy: Exploring the Mechanisms of Pyridoxine Toxicity

Vitamin B-6 in the form of pyridoxine (PN) is commonly used by the general population. The use of PN-containing supplements has gained lots of attention over the past years as they have been related to the development of peripheral neuropathy. In light of this, the number of reported cases of adverse health effects due to the use of vitamin B-6 have increased. Despite a long history of study, the pathogenic mechanisms associated with PN toxicity remain elusive. Therefore, the present review is focused on investigating the mechanistic link between PN supplementation and sensory peripheral neuropathy. Excessive PN intake induces neuropathy through the preferential injury of sensory neurons. Recent reports on hereditary neuropathy due to pyridoxal kinase (PDXK) mutations may provide some insight into the mechanism, as genetic deficiencies in PDXK lead to the development of axonal sensory neuropathy. High circulating concentrations of PN may lead to a similar condition via the inhibition of PDXK. The mechanism behind PDXK-induced neuropathy is unknown; however, there is reason to believe that it may be related to γ-aminobutyric acid (GABA) neurotransmission. Compounds that inhibit PDXK lead to convulsions and reductions in GABA biosynthesis. The absence of central nervous system-related symptoms in PDXK deficiency could be due to differences in the regulation of PDXK, where PDXK activity is preserved in the brain but not in peripheral tissues. As PN is relatively impermeable to the blood-brain barrier, PDXK inhibition would similarly be confined to the peripheries and, as a result, GABA signaling may be perturbed within peripheral tissues, such as sensory neurons. Perturbed GABA signaling within sensory neurons may lead to excitotoxicity, neurodegeneration, and ultimately, the development of peripheral neuropathy. For several reasons, we conclude that PDXK inhibition and consequently disrupted GABA neurotransmission is the most plausible mechanism of toxicity.

Optimizing Multivitamin Supplementation for Sleeve Gastrectomy Patients

Purpose

Micronutrient deficiencies are frequently reported after sleeve gastrectomy (SG), and therefore lifelong daily multivitamin supplementation is highly recommended. Based on literature and the results of a previous randomized controlled trial, a specialized multivitamin supplement for SG patients was further optimized (WLS Optimum 2.0, FitForMe). The present study reports on its short-term effectiveness.

Materials and Methods

An open-label study was performed in which 76 patients were included to receive WLS Optimum 2.0 for 12 months (Opt 2.0 group). This group was compared with a group of 75 patients that had received WLS Optimum 1.0 for 12 months during a previous study (Opt 1.0 group).

Results

Intention-to-treat analysis (Opt 1.0, n = 69; Opt 2.0, n = 75) showed higher serum levels of vitamin B12, vitamin B6, and zinc, and a lower prevalence of deficiencies for vitamin B12 and phosphate in the Opt 2.0 group. MCV and serum folic acid levels were higher in the Opt 1.0 group. Over the 12-month study period, mean increase in serum levels of phosphate, vitamin B6, and zinc was higher in the Opt 2.0 group, and MCV and serum vitamin D levels increased more in the Opt 1.0 group.

Conclusion

The present study showed that the use of a specialized multivitamin supplement for SG patients is effective at preventing deficiencies for most vitamins and minerals, specifically in compliant patients. However, a strict follow-up regime remains necessary to monitor nutritional status and to improve patient compliance.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11695-021-05282-4.

4'-O-methylpyridoxine: Preparation from Ginkgo biloba Seeds and Cytotoxicity in GES-1 Cells

Ginkgo biloba seeds are wildly used in the food and medicine industry. It has been found that 4′-O-methylpyridoxine (MPN) is responsible for the poisoning caused by G. biloba seeds. The objective of this study was to explore and optimize the extraction method of MPN from G. biloba seeds, and investigate its toxic effect on human gastric epithelial cells (GES-1) and the potential related mechanisms. The results showed that the extraction amount of MPN was 1.933 μg/mg, when extracted at 40 °C for 100 min, with the solid–liquid ratio at 1:10. MPN inhibited the proliferation of GES-1 cells, for which the inhibition rate was 38.27% when the concentration of MPN was 100 μM, and the IC₅₀ value was 127.80 μM; meanwhile, the cell cycle was arrested in G2 phase. High concentration of MPN (100 μM) had significant effects on the nucleus of GES-1 cells, and the proportion of apoptotic cells reached 43.80%. Furthermore, the Western blotting analysis showed that MPN could reduce mitochondrial membrane potential by increasing the expression levels of apoptotic proteins Caspase 8 and Bax in GES-1 cells. In conclusion, MPN may induce apoptosis in GES-1 cells, which leads to toxicity in the human body.

Effects of Alzheimer-Like Pathology on Homocysteine and Homocysteic Acid Levels-An Exploratory In Vivo Kinetic Study

Hyperhomocysteinemia has been suggested potentially to contribute to a variety of pathologies, such as Alzheimer’s disease (AD). While the impact of hyperhomocysteinemia on AD has been investigated extensively, there are scarce data on the effect of AD on hyperhomocysteinemia. The aim of this in vivo study was to investigate the kinetics of homocysteine (HCys) and homocysteic acid (HCA) and effects of AD-like pathology on the endogenous levels. The mice received a B-vitamin deficient diet for eight weeks, followed by the return to a balanced control diet for another eight weeks. Serum, urine, and brain tissues of App^NL-G-F knock-in and C57BL/6J wild type mice were analyzed for HCys and HCA using LC-MS/MS methods. Hyperhomocysteinemic levels were found in wild type and knock-in mice due to the consumption of the deficient diet for eight weeks, followed by a rapid normalization of the levels after the return to control chow. Hyperhomocysteinemic App^NL-G-F mice had significantly higher HCys in all matrices, but not HCA, compared to wild type control. Higher serum concentrations were associated with elevated levels in both the brain and in urine. Our findings confirm a significant impact of AD-like pathology on hyperhomocysteinemia in the App^NL-G-F mouse model. The immediate normalization of HCys and HCA after the supply of B-vitamins strengthens the idea of a B-vitamin intervention as a potentially preventive treatment option for HCys-related disorders such as AD.

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.

Discovery of Gut Bacteria Specific to Alzheimer's Associated Diseases is a Clue to Understanding Disease Etiology: Meta-Analysis of Population-Based Data on Human Gut Metagenomics and Metabolomics

Alzheimer's disease (AD)-associated sequence (ADAS) of cultured fecal bacteria was discovered in human gut targeted screening. This study provides important information to expand our current understanding of the structure/activity relationship of ADAS and putative inhibitors/activators that are potentially involved in ADAS appearance/disappearance. The NCBI database analysis revealed that ADAS presents at a large proportion in American Indian Oklahoman (C&A) with a high prevalence of obesity/diabetes and in colorectal cancer (CRC) patients from the US and China. An Oklahoman non-native group (NNI) showed no ADAS. Comparison of two large US populations reveals that ADAS is more frequent in individuals aged ≥66 and in females. Prevalence and levels of fecal metabolites are altered in the C&A and CRC groups versus controls. Biogenic amines (histamine, tryptamine, tyramine, phenylethylamine, cadaverine, putrescine, agmatine, spermidine) that present in food and are produced by gut microbiota are significantly higher in C&A (e.g., histamine/histidine 95-fold) versus NNI (histamine/histidine 16-fold). The majority of these bio-amines are cytotoxic at concentrations found in food. Inositol phosphate signaling implicated in AD is altered in C&A and CRC. Tryptamine stimulated accumulation of inositol phosphate. The seizure-eliciting tryptamine induced cytoplasmic vacuolization and vesiculation with cell fragmentation. Present additions of ADAS-carriers at different ages including infants led to an ADAS-comprising human sample size of 2,830 from 27 studies from four continents (North America, Australia, Asia, Europe). Levels of food-derived monoamine oxidase inhibitors and anti-bacterial compounds, the potential modulators of ADAS-bacteria growth and biogenic amine production, were altered in C&A versus NNI. ADAS is attributable to potentially modifiable risk factors of AD associated diseases.

Isolated Pyridoxine Deficiency Presenting as Muscle Spasms in a Patient With Type 2 Diabetes: A Case Report and Literature Review

Pyridoxine is an important co-factor for many biochemical reactions in cellular metabolism related to the synthesis and catabolism of amino acids, fatty acids, neurotransmitters. Deficiency of pyridoxine results in impaired transcellular signaling between neurons and presents with muscular convulsions, hyperirritability, and peripheral neuropathy. Deficiency of pyridoxine is usually found in association with other vitamin B deficiencies such as folate (vitamin B9) and cobalamin (vitamin B12). Isolated pyridoxine deficiency is extremely rare. We present the case of a 59-year old female with type 2 diabetes who complained of painful muscle spasms. Her muscle spasms involved in both feet, which have spread proximally to her legs. She also experienced intermittent muscle spasms in her left arm, which is not alleviated by baclofen, cyclobenzaprine. Her plasma pyridoxal 5-phosphate confirmed pyridoxine deficiency. Vitamins B1, B3, B12, and folate were within normal limits. The patient received standard-dose intramuscular pyridoxine injections for three weeks followed by oral supplements for 3 months and her symptoms resolved. This case illustrates the rare instance of isolated pyridoxine deficiency in type 2 diabetes patient manifesting as myoclonic muscle spasms involving the legs and arms in the absence of objective polyneuropathy. Pyridoxine level should, therefore, be assessed in patients with type 2 diabetes, including newly diagnosed patients.

[Choosing of therapy for a patient with dorsalgia]

Dorsalgia is one of the most common skeletal muscle syndromes. Dorsalgia often develops in patients of older age groups with polymorbidity that requires the appointment of a large number of medications. In these conditions, the choice of effective and safe therapy is a difficult problem. Discusses management of a patient suffering dorsalgia with comorbidities, the risks of complications of therapy, possible safety treatment, in particular, through the use of combination therapy.

Safety and efficacy of supplements in pregnancy

Pregnancy is a time where expectant mothers often focus on their diet to improve their own health and to preserve the future health of their children. There is much conflicting information in the public domain about the safety and/or efficacy of nutritional supplements during pregnancy. Despite this, the market for supplements is growing. This review discusses the roles of critical nutrients in pregnancy and the available evidence on the use of supplements to reduce risks and improve maternal and fetal outcomes. Recommendations are made for pregnant women, taking into account safety data and tolerable upper intakes set for pregnant women. It is important for dieticians, nutritionists, physicians, and other healthcare providers to be able to offer accurate and evidence-based advice on supplement use in pregnancy. Routine supplementation may not be necessary for all, but individuals at risk are identified.

Effect of Trace Minerals and B Vitamins on the Proliferation/Cytotoxicity and Mineralization of a Gilthead Seabream Bone-Derived Cell Line

Trace minerals and vitamins are known modulators of bone metabolism, and dietary optimization of these components may improve skeletal development and reduce the occurrence of skeleton deformities in farmed fish. As for larval stages, mineral and water-soluble vitamin nutrition requirements are lacking in research efforts and knowledge is scarce. An in vitro cell system developed from gilthead seabream vertebra and capable of mineralization was used to assess the effect of B vitamins (thiamin and pyridoxine) and trace minerals (copper, manganese, and zinc in a sulfated and chelated form) on cell proliferation and extracellular matrix (ECM) mineralization. Dependent on dose, inhibition of cellular proliferation and/or cytotoxic effects was observed for all nutrients tested and LD₅₀ values were determined: copper, 67.4-69.5 ppm; manganese, 20.9-29.8 ppm; zinc, 37.1-42.8 ppm in sulfated and chelated form respectively; thiamin, 6273 ppm; pyridoxine, 14226 ppm. ECM mineralization was enhanced by mineral (dose and form dependent) and vitamin (dose dependent) supplementation, at non-toxic concentrations below the determined LD_50s. This in vitro work confirmed the mineralogenic action of trace minerals and water-soluble vitamins and provided valuable insights for subsequent in vivo nutritional trials.

Nutritional and medical food therapies for diabetic retinopathy

Diabetic retinopathy (DR) is a form of microangiopathy. Reducing oxidative stress in the mitochondria and cell membranes decreases ischemic injury and end-organ damage to the retina. New approaches are needed, which reduce the risk and improve the outcomes of DR while complementing current therapeutic approaches. Homocysteine (Hcy) elevation and oxidative stress are potential therapeutic targets in DR. Common genetic polymorphisms such as those of methylenetetrahydrofolate reductase (MTHFR), increase Hcy and DR risk and severity. Patients with DR have high incidences of deficiencies of crucial vitamins, minerals, and related compounds, which also lead to elevation of Hcy and oxidative stress. Addressing the effects of the MTHFR polymorphism and addressing comorbid deficiencies and insufficiencies reduce the impact and severity of the disease. This approach provides safe and simple strategies that support conventional care and improve outcomes. Suboptimal vitamin co-factor availability also impairs the release of neurotrophic and neuroprotective growth factors. Collectively, this accounts for variability in presentation and response of DR to conventional therapy. Fortunately, there are straightforward recommendations for addressing these issues and supporting traditional treatment plans. We have reviewed the literature for nutritional interventions that support conventional therapies to reduce disease risk and severity. Optimal combinations of vitamins B1, B2, B6, L-methylfolate, methylcobalamin (B12), C, D, natural vitamin E complex, lutein, zeaxanthin, alpha-lipoic acid, and n-acetylcysteine are identified for protecting the retina and choroid. Certain medical foods have been successfully used as therapy for retinopathy. Recommendations based on this review and our clinical experience are developed for clinicians to use to support conventional therapy for DR. DR from both type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) have similar retinal findings and responses to nutritional therapies.

Effect of Double Substitution in Cationic Chitosan Derivatives on DNA Transfection Efficiency

Recently, much effort has been expended on the development of non-viral gene delivery systems based on polyplexes of nucleic acids with various cationic polymers. Natural polysaccharide derivatives are promising carriers due to their low toxicity. In this work, chitosan was chemically modified by a reaction with 4-formyl-n,n,n-trimethylanilinium iodide and pyridoxal hydrochloride and subsequent reduction of the imine bond with NaBH₄. This reaction yielded three novel derivatives, n-[4-(n’,n’,n’-trimethylammonium)benzyl]chitosan chloride (TMAB-CS), n-[(3-hydroxy-5-(hydroxymethyl)-2-methyl-4-pyridine)methyl]chitosan chloride (Pyr-CS), and n-[4-(n’,n’,n’’-trimethylammonium)benzyl]-n-[(3-hydroxy-5-(hydroxymethyl)-2-methyl-4-pyridine)methyl]chitosan chloride (PyrTMAB-CS). Their structures and degrees of substitution were established by ¹H NMR spectroscopy as DS₁ = 0.22 for TMAB-CS, DS₂ = 0.28 for Pyr-CS, and DS₁ = 0.21, DS₂ = 0.22 for PyrTMAB-CS. Dynamic light scattering measurements revealed that the new polymers formed stable polyplexes with plasmid DNA encoding the green fluorescent protein (pEGFP-N3) and that the particles had the smallest size (110–165 nm) when the polymer:DNA mass ratio was higher than 5:1. Transfection experiments carried out in the HEK293 cell line using the polymer:DNA polyplexes demonstrated that Pyr-CS was a rather poor transfection agent at polymer:DNA mass ratios less than 10:1, but it was still more effective than the TMAB-CS and PyrTMAB-CS derivatives that contained a quaternary ammonium group. By contrast, TMAB-CS and PyrTMAB-CS were substantially more effective than Pyr-CS at higher polymer:DNA mass ratios and showed a maximum efficiency at 200:1 (50%–70% transfected cells). Overall, the results show the possibility of combining substituent effects in a single carrier, thereby increasing its efficacy.