Thiamine deficiency in diabetes, obesity and bariatric surgery: Recipes for diabetic ketoacidosis.

Diabetic ketoacidosis (DKA) is a life-threatening condition affecting individuals with diabetes characterised by hyperglycaemia, metabolic acidosis and ketonemia. The incidence and financial burden of DKA is still high. Thiamine deficiency is well documented in patients with DKA and could be associated with cardiac dysfunction in those patients. Thiamine deficiency leads to cardiac dysfunction, neuronal death and worsens the prognosis of DKA. There is an existing metabolic relationship between thiamine deficiency in diabetes, obesity and bariatric surgery. Careful monitoring of thiamine, along with other vitamins, is essential for diabetic patients, obese individuals and postbariatric surgery. Further research and clinical studies are urgently needed to assess the following: (1) Whether diabetes, obesity and bariatric surgery make individuals more prone to have DKA related to thiamine deficiency and (2) Whether supplementation of thiamine can protect diabetic patients, obese subjects and individuals undergoing bariatric surgery from DKA. This review summarises the biochemistry of thiamine and the existing metabolic relationships between thiamine deficiency in DKA, diabetes, obesity and bariatric surgery. Primary and family physicians have an important role in ensuring adequate replacement of thiamine in individuals with diabetes, obesity and bariatric surgery.

Assessment of Erythrocyte Transketolase, Whole Blood Thiamine Diphosphate, and Human Milk Thiamine Concentrations to Identify Infants and Young Children Responding Favorably to Therapeutic Thiamine Administration: Findings from the Lao Thiamine Study, a Prospective Cohort Study.

Background: There is limited information on relationships among biomarkers of thiamine status (whole blood thiamine diphosphate [ThDP], erythrocyte transketolase activity coefficient [ETKac], and human milk thiamine [MTh]) and clinical manifestations of thiamine deficiency. Objectives: This study aimed to explore correlations among these biomarkers and thiamine responsive disorders (TRDs), a diagnosis based on favorable clinical response to thiamine. Methods: Hospitalized infants and young children (aged 21 d to <18 mo) with respiratory, cardiac, and/or neurological symptoms suggestive of thiamine deficiency were treated with parenteral thiamine (100 mg daily) for ≥3 d alongside other treatments and re-examined systematically. Clinical case reports were reviewed by 3 pediatricians, who determined TRD or non-TRD status. Children in a community comparison group were matched by age, sex, and residence. Venous whole blood ThDP and MTh were determined by high-performance liquid chromatography fluorescence detection and ETKac in washed erythrocytes by ultraviolet spectrophotometry. Associations between biomarkers were assessed using Spearman correlations, and biomarker cutoffs predictive of TRD and ETKac >1.25 were explored using area under the receiver operating characteristic curve framework. Results: Thiamine biomarkers were available for 287 hospitalized children and 228 community children (mean age 4.7 mo; 59.4% male). Median (interquartile range [IQR]) ThDP and ETKac were 66.9 nmol/L (IQR: 41.4, 96.9 nmol/L) and 1.25 nmol/L (IQR: 1.11, 1.48 nmol/L), respectively, among hospitalized children, and 64.1 nmol/L (IQR: 50.0, 85.3 nmol/L) and 1.22 nmol/L (IQR: 1.12, 1.37 nmol/L) among 228 community children (P > 0.05 for both). Forty-five percent of breastfeeding mothers of infants <6 mo had MTh <90 µg/L. ThDP and ETKac, but not MTh, were significantly different between 152 children with TRD and 122 without TRD, but overlapping distributions undermined prediction of individual responses to thiamine. Conclusions: Although ETKac, ThDP, and MTh are useful biomarkers of population thiamine status, none of the biomarkers reliably identified individual children with TRD. ThDP is more practical for population assessment because preparing washed erythrocytes is not required.This trial was registered at clinicaltrials.gov as NCT03626337.

Exploring the Therapeutic Potential of Benfotiamine in a Sporadic Alzheimer's-Like Disease Rat Model: Insights into Insulin Signaling and Cognitive function.

Alzheimer's disease (AD) is a complex neurodegenerative process, also considered a metabolic condition due to alterations in glucose metabolism and insulin signaling pathways in the brain, which share similarities with diabetes. This study aimed to investigate the therapeutic effects of benfotiamine (BFT), a vitamin B1 analog, in the early stages of the neurodegenerative process in a sporadic model of Alzheimer's-like disease induced by intracerebroventricular injection of streptozotocin (STZ). Supplementation with 150 mg/kg of BFT for 7 days reversed the cognitive impairment in short- and long-term memories caused by STZ in rodents. We attribute these effects to BFT's ability to modulate glucose transporters type 1 and 3 (GLUT1 and GLUT3) in the hippocampus, inhibit GSK3 activity in the hippocampus, and modulate the insulin signaling in the hippocampus and entorhinal cortex, as well as reduce the activation of apoptotic pathways (BAX) in the hippocampus. Therefore, BFT emerges as a promising and accessible intervention in the initial treatment of conditions similar to AD.

Brain MRI: A safe and a specific tool in the diagnosis of Gayet Wernicke's encephalopathy in pregnant women: Case report.

Gayet-Wernicke encephalopathy (GWE) is a neuropsychiatric syndrome due to Vitamin B1 (thiamine) deficiency, fatal in 30% of cases and preventable if treatment is initiated early, characterized by the classic triad of encephalopathy, ocular involvement: ophthalmoplegia and/or nystagmus and ataxia. GWE is mainly observed in alcoholics, but can also appear in any state of malnutrition. In obstetrics, hyperemesis gravidarum can be complicated by GWE due to low thiamine stores and increased thiamine requirements. We report a case of Gayet-Wernicke encephalopathy complicating incoercible vomiting in a pregnant woman.

Wernicke Encephalopathy: Typical and Atypical Findings in Alcoholics and Non-Alcoholics and Correlation with Clinical Symptoms.

PURPOSE: Clinical diagnosis of Wernicke encephalopathy (WE) can be challenging due to incomplete presentation of the classical triad. The aim was to provide an update on the relevance of standard MRI and to put typical and atypical imaging findings into context with clinical features. METHODS: In this two-center retrospective observational study, the local radiology information system was searched for consecutive patients with clinical or imaging suspicion of WE. Two independent raters evaluated T2-weighted imaging (WI), fluid-attenuation inversion recovery (FLAIR), diffusion WI (DWI), T2*WI and/or susceptibility WI (SWI), and contrast-enhanced (CE)-T1WI, and noted the involvement of typical (i.e., mammillary bodies (MB), periaqueductal grey (PAG), thalamus, hypothalamus, tectal plate) and atypical (all others) lesion sites. Unusual signal patterns like hemorrhages were also documented. Reported clinical features together with the diagnostic criteria of the latest guidelines of the European Federation of Neurological Societies (EFNS) were used to test for relationships with MRI biomarkers. RESULTS: 47 patients with clinically confirmed WE were included (Jan '99-Apr '23; mean age, 53 yrs; 70% males). Interrater reliability for imaging findings was substantial (κ = 0.71), with lowest agreements for T2WI (κ = 0.85) compared to all other sequences and for PAG (κ = 0.65) compared to all other typical regions. In consensus, 77% (n = 36/47) of WE cases were rated MRI positive, with FLAIR (n = 36/47, 77%) showing the strongest relation (χ2 = 47.0; P < 0.001) compared to all other sequences. Microbleeds in the MB were detected in four out of ten patients who received SWI, not visible on corresponding T2*WI. Atypical findings were observed in 23% (n = 11/47) of cases, always alongside typical findings, in both alcoholics (n = 9/44, 21%) and non-alcoholics (n = 2/3, 67%). Isolated involvement of structures, explicitly PAG (n = 4/36; 11%) or MB (n = 1/36; 3%), was present but observed less frequently than combined lesions (n = 31/36; 86%). A cut-off width of 2.5 mm for the PAG on 2D axial FLAIR was established between cases and age- and sex-matched controls. An independent association was demonstrated only between short-term memory loss and changes in the MB (OR = 2.2 [95% CI: 1.1-4.5]; P = 0.024). In retrospect, EFNS criteria were positive (≥ 2 out of 4) in every case, but its count (range, 2-4) showed no significant (P = 0.427) relationship with signal changes on standard MRI. CONCLUSION: The proposed sequence protocol (FLAIR, DWI, SWI and T1WI + CE) yielded good detection rates for neuroradiological findings in WE, with SWI showing microbleeds in the MB with superior detectability. However, false negative results in about a quarter of cases underline the importance of neurological alertness for the diagnosis. Awareness of atypical MRI findings should be raised, not only in non-alcoholics. There is limited correlation between clinical signs and standard MRI biomarkers.

Low thiamine status in adults following low-carbohydrate / ketogenic diets: a cross-sectional comparative study of micronutrient intake and status.

BACKGROUND: Low-carbohydrate diets (LCD) are popular for weight loss but lack evidence about micronutrient sufficiency in real-life use. This study assessed the intake and biochemical status of selected micronutrients in people voluntarily following LCDs. METHODS: A cross-sectional study was conducted (2018-20) among 98 adults recruited as self-reporting either LCD (n = 49) or diets not restricting carbohydrates (controls; n = 49). Diets were assessed using the 130-item EPIC-Norfolk food-frequency questionnaire. Red-blood-cell thiamine diphosphate (TDP) was measured for thiamine status using HPLC. Plasma magnesium, zinc, copper, and selenium were measured using inductively coupled plasma mass spectrometry. Between-group biomarker comparisons were conducted using ANCOVA and adjusted for age, sex, body mass index (BMI), and diabetes status. RESULTS: LCD-followers (26% male, median age 36 years, median BMI 24.2 kg/m2) reported adhering to LCDs for a median duration of 9 months (IQR 4-36). The most followed LCD type was 'their own variations of LCD' (30%), followed by ketogenic (23%), 'palaeolithic' (15%), and Atkins diets (8%). Among controls, 41% were male (median age 27 years, median BMI 23 kg/m2). Median macronutrient intakes for LCD vs control groups were carbohydrate 16%Energy (E) vs. 50%E; protein 25%E vs. 19%E; and fat 55%E vs 34%E (saturated fat 18%E vs. 11%E). Two-thirds of LCD followers (32/49) and half of the controls (24/49) reported some use of dietary supplements (p = 0.19). Among LCD-followers, assessing from food data only, 21 (43%) failed to meet the reference nutrient intake (RNI) for thiamine (vs.14% controls, p = 0.002). When thiamine from supplementation (single- or multivitamin) was included, there appeared to be no difference in thiamine intake between groups. Still, red-blood-cell TDP was lower in LCD-followers than controls (407 ± 91 vs. 633 ± 234 ng/gHb, p < 0.001). Three LCD-followers were thiamine-deficient (RBC thiamine < 275 ng/gHb) vs. one control. There were no significant differences in dietary intakes or plasma concentrations of magnesium, zinc, copper, and selenium between groups. CONCLUSIONS: Following LCDs is associated with lower thiamine intake and TDP status than diets without carbohydrate restriction, incompletely corrected by supplement use. These data, coupled with a lack of RCT evidence on body weight control, do not support recommending LCDs for weight management without appropriate guidance and diet supplementation.

Suspected Thiamine Deficiency Secondary to Chronic Gastrointestinal Illness: A Case Report.

Introduction: Thiamine deficiency, also known as beriberi, is a nutritional disorder caused by a lack of thiamine (vitamin B1) in the diet. It can occur in 2 forms: dry beriberi, which affects the nervous system, and wet beriberi, which affects the cardiovascular system. Gastrointestinal beriberi is a subtype that affects the digestive system and can lead to multisystem involvement. In the United States (US), thiamine deficiency often arises from chronic malnutrition secondary to alcoholism, known as Wernicke-Korsakoff Syndrome. Case Presentation: A 45-year-old female with no known past medical history or alcohol use disorder came to the emergency department with an altered mental status and with a history of intractable nausea and vomiting for several months prior to presentation. During intake, the medical team discovered she had bilateral lower extremity weakness and an anion gap metabolic acidosis. Her inpatient workup ruled out meningitis, encephalitis, peritonitis, diabetic ketoacidosis, and cerebrovascular accident. A thiamine deficiency was the most probable cause of her presentation, secondary to her protracted history of vomiting and poor oral medication intake. Refeeding syndrome complicated her hospitalization. After replenishing thiamine, the patient experienced significant improvement in mental status and lower extremity weakness. The healthcare team later discharged her with home physical therapy rehabilitation and nutritional counseling. Conclusion: Thiamine deficiency is not common in the US. However, this case highlights the importance of including this deficiency in the differential when a patient arrives with a history of malnourishment secondary to a gastrointestinal illness with signs of altered mental status and neurological symptoms.

In vitro inhibitor effect and molecular docking of thiamine (vitamin B1), riboflavin (vitamin B2), and reference inhibitor captopril on angiotensin-converting enzyme purified from sheep plasma.

OBJECTIVE: Angiotensin-converting enzyme (ACE, EC 3.4.15.1) is a very important factor in the regulation of blood pressure. Also, the inhibition of ACE with natural compounds has been a very important research area in the treatment of high blood pressure. ACE was purified and characterized from sheep plasma. Molecular docking studies and the inhibition effect of thiamine, riboflavin, and captopril on ACE were investigated. METHODS: Herein, ACE was purified from sheep plasma by affinity chromatography. The effect of thiamine and riboflavin on ACE was researched. Molecular docking studies were performed to understand the molecular interactions between thiamine, riboflavin, and captopril with ACE. RESULTS: The purification coefficient was found to be 8636 fold. The binding energy of thiamine, riboflavin, and captopril was found to be -6.7 kcal/mol, -8.1 kcal/mol, and -5.5 kcal/mol, respectively. Thiamine conformed to three conventional hydrogen bonds with ASP:415, HIS:513, and LYS:454. Riboflavin formed four conventional hydrogen bonds with GLN:281, GLU:376, THR:282, and TYR:520. Captopril formed two conventional hydrogen bonds with ARG:124, one conventional hydrogen bond with TYR:62 and ASN:85, and one carbon-hydrogen bond with ASN:66. Molecular docking results showed that thiamine, riboflavin, and captopril interacted with ACE through hydrogen bonding and hydrophobic interactions. Thiamine and riboflavin indicated significant inhibition effects on ACE. The IC50 values of thiamine, riboflavin, and captopril were found as 960.56 µM, 11.02 µM, and 1.60 nM, respectively. Ki values for thiamine, riboflavin, and captopril were determined as 1352.04 µM, 12.30 µM, and 1.06 nM, respectively. CONCLUSION: In this work, it was concluded that thiamine and riboflavin may have preventive and therapeutical impacts against high blood pressure with their ACE inhibitor effect. Thiamine and riboflavin showed a lower inhibitory effect with a higher IC50 than captopril. However, when the inhibitory effect of thiamine and riboflavin vitamins is compared to captopril, it is concluded that they may be natural inhibitors with fewer side effects.

Derivation of two iPSC lines (KAIMRCi004-A, KAIMRCi004-B) from a Saudi patient with Biotin-Thiamine-responsive Basal Ganglia Disease (BTBGD) carrying homozygous pathogenic missense variant in the SCL19A3 gene.

The neurometabolic disorder known as biotin-thiamine-responsive basal ganglia disease (BTBGD) is a rare autosomal recessive condition linked to bi-allelic pathogenic mutations in the SLC19A3 gene. BTBGD is characterized by progressive encephalopathy, confusion, seizures, dysarthria, dystonia, and severe disabilities. Diagnosis is difficult due to the disease's rare nature and diverse clinical characteristics. The primary treatment for BTBGD at this time is thiamine and biotin supplementation, while its long-term effectiveness is still being investigated. In this study, we have generated two clones of induced pluripotent stem cells (iPSCs) from a 10-year-old female BTBGD patient carrying a homozygous mutation for the pathogenic variant in exon 5 of the SLC19A3 gene, c.1264A > G (p.Thr422Ala). We have confirmed the pluripotency of the generated iPS lines and successfully differentiated them to neural progenitors. Because our understanding of genotype-phenotype correlations in BTBGD is limited, the establishment of BTBGD-iPSC lines with a homozygous SLC19A3 mutation provides a valuable cellular model to explore the molecular mechanisms underlying SLC19A3-associated cellular dysfunction. This model holds potential for advancing the development of novel therapeutic strategies.

Exploring Marchiafava-Bignami Disease: A Rare Presentation in a Young Pregnant Female.

Marchiafava-Bignami disease (MBD) is uncommon and typically linked with persistent alcohol consumption; nevertheless, instances have been reported in non-alcoholic individuals with nutritional deficiencies. Depending on the severity, this condition may manifest as acute, subacute, or chronic neurological signs and symptoms, ranging from moderate dysarthria or mild disorientation to coma and death. We report a case of a 30-year-old, 14-week pregnant female who presented with complaints of persistent vomiting and loss of appetite. She was found to have achalasia cardia on upper GI endoscopy. Later, she developed confusion, irrelevant talks and her speech was incomprehensible. An MRI of the brain was done which showed features likely that of MBD. She was started high dose intravenous thiamine to which she responded brilliantly.

Long term administration of thiamine disulfide improves FOXO1/PEPCK pathway in liver to reduce insulin resistance in type 1 diabetes rat model.

OBJECTIVE: The main objective of this study was to find if thiamine disulfide (TD) lowers blood glucose level and improves insulin resistance (IR) in liver and muscle in rats with chronic type 1 diabetes (T1DM) using euglycemic-hyperinsulinemic clamp technique. METHODS: A total of fifty male Wistar rats were assigned to five groups consisted of: non-diabetic control (NDC), diabetic control (DC), diabetic treated with thiamine disulfide (D-TD), diabetic treated with insulin (D-insulin), and diabetic treated with both TD and insulin (D-insulin+TD). Diabetes was induced by a 60 mg/kg dose of streptozotocin. Blood glucose levels, pyruvate tolerance test (PTT), intraperitoneal glucose tolerance test (IPGTT), levels of glycosylated hemoglobin (HbA1c), glucose infusion rate (GIR), liver and serum lipid profiles, liver glycogen stores, liver enzymes ([ALT], [AST]), and serum calcium and magnesium levels. were evaluated. Additionally, gene expression levels of phosphoenolpyruvate carboxykinase (Pepck), forkhead box O1 (Foxo1), and glucose transporter type 4 (Glut4) were assessed in liver and skeletal muscle tissues. RESULTS: Blood glucose level was reduced by TD treatment. In addition, TyG index, HOMA-IR, serum and liver lipid profiles, HbA1c levels, and expressions of Foxo1 and Pepck genes were decreased significantly (P<0.05) in all the treated groups. However, TD did not influence Glut4 gene expression, but GIR as a critical index of IR were 5.0±0.26, 0.29±0.002, 1.5±0.07, 0.9±0.1 and 1.3±0.1 mg.min-1Kg-1 in NDC, DC, D-TD, D-insulin and D-insulin+TD respectively. CONCLUSIONS: TD improved IR in the liver primarily by suppressing gluconeogenic pathways, implying the potential use of TD as a therapeutic agent in diabetes.

Role of Thiamine Supplementation in the Treatment of Chronic Heart Failure: An Updated Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Chronic heart failure (CHF) has always posed a significant threat to human survival and health. The efficacy of thiamine supplementation in CHF patients remains uncertain. HYPOTHESIS: Receiving supplementary thiamine may not confer benefits to patients with CHF. METHODS: A comprehensive search was conducted across the Cochrane Library, PubMed, EMBASE, ClinicalTrials.gov, and Web of Science databases up until May 2023 to identify articles investigating the effects of thiamine supplementation in CHF patients. Predefined criteria were utilized for selecting data on study characteristics and results. RESULTS: Seven randomized, double-blind, controlled trials (five parallel trials and two crossover trials) involving a total of 274 patients were enrolled. The results of the meta-analysis pooling these studies did not reveal any significant effect of thiamine treatment compared with placebo on left ventricular ejection fraction (WMD = 1.653%, 95% CI:  -1.098 to 4.405, p = 0.239, I2 = 61.8%), left ventricular end-diastolic volume (WMD = -6.831 mL, 95% CI:  -26.367 to 12.704, p = 0.493, I2 = 0.0%), 6-min walking test (WMD = 16.526 m, 95% CI:  -36.582 to 69.634, p = 0.542, I2 = 66.3%), N-terminal pro-B type natriuretic peptide (WMD = 258.150 pg/mL, 95% CI:  -236.406 to 752.707, p = 0.306, I2 = 21.6%), or New York Heart Association class (WMD = -0.223, 95% CI:  -0.781 to 0.335, p = 0.434, I2 = 87.1%). However, it effectively improved the status of thiamine deficiency (TD). CONCLUSIONS: Our meta-analysis indicates that thiamine supplementation does not have a direct therapeutic effect on CHF, except for correcting TD.

Wernicke Encephalopathy Caused by Avoidance-Restrictive Food Intake Disorder in a Child: A Case-Based Review.

BACKGROUND: Wernicke encephalopathy (WE) is an acute and potentially fatal neuropsychiatric disorder resulting from thiamine deficiency: its etiology and clinical presentation can be heterogeneous and arduously recognized, especially in children and adolescents. CASE PRESENTATION: An 8-year-old girl arrived to the emergency room with ataxic gait, nystagmus, and mental confusion after a 10-day history of repeated severe vomiting; her recent clinical history was characterized by restricted nutrition due to a choking phobia, which caused substantial weight loss. Brain magnetic resonance imaging revealed a bilaterally increased T2 signal in the medial areas of the thalami and cerebral periaqueductal region. Diagnosis of WE based on clinical and neuroradiological findings was established and confirmed after labwork showing low serum thiamine. Following psychiatric evaluation, the patient was also diagnosed with avoidance-restrictive food intake disorder (ARFID), which required starting cognitive behavioral therapy and introducing aripiprazole. The patient displayed improvement of the radiological findings after one month and complete resolution of her neurological symptoms and signs. CONCLUSIONS: Eating disorders like ARFID might forerun acute signs of WE; this possibility should be considered even in pediatric patients, especially when atypical neurological pictures or feeding issues come out.

Biotin Homeostasis and Human Disorders: Recent Findings and Perspectives.

Biotin (vitamin B7, or vitamin H) is a water-soluble B-vitamin that functions as a cofactor for carboxylases, i.e., enzymes involved in the cellular metabolism of fatty acids and amino acids and in gluconeogenesis; moreover, as reported, biotin may be involved in gene regulation. Biotin is not synthesized by human cells, but it is found in food and is also produced by intestinal bacteria. Biotin status/homeostasis in human individuals depends on several factors, including efficiency/deficiency of the enzymes involved in biotin recycling within the human organism (biotinidase, holocarboxylase synthetase), and/or effectiveness of intestinal uptake, which is mainly accomplished through the sodium-dependent multivitamin transporter. In the last years, administration of biotin at high/"pharmacological" doses has been proposed to treat specific defects/deficiencies and human disorders, exhibiting mainly neurological and/or dermatological symptoms and including biotinidase deficiency, holocarboxylase synthetase deficiency, and biotin-thiamine-responsive basal ganglia disease. On the other hand, according to warnings of the Food and Drug Administration, USA, high biotin levels can affect clinical biotin-(strept)avidin assays and thus lead to false results during quantification of critical biomarkers. In this review article, recent findings/advancements that may offer new insight in the abovementioned research fields concerning biotin will be presented and briefly discussed.

Efficacy and Safety of Hydrocortisone, Ascorbic Acid, and Thiamine Combination Therapy for the Management of Sepsis and Septic Shock: A Systematic Review and Meta-Analysis of Randomised Controlled Trials.

INTRODUCTION: This systematic review aimed to assess the efficacy and safety of hydrocortisone, ascorbic acid, and thiamine (HAT) combination therapy in patients with sepsis and septic shock. METHODS: We conducted a database search in MEDLINE, Embase, CENTRAL, Web of Science, and CNKI for randomised controlled trials (RCTs) comparing HAT against placebo/standard of care or against hydrocortisone in sepsis/septic shock patients. Outcomes included mortality, ICU/hospital length of stay (LOS), vasopressor durations, mechanical ventilation durations, change in SOFA at 72 h, and adverse events. RCT results were pooled in random-effects meta-analyses. Quality of evidence was assessed using GRADE. RESULTS: Fifteen RCTs (N = 2,594) were included. At 72 h, HAT reduced SOFA scores from baseline (mean difference [MD] -1.16, 95% confidence interval [CI]: -1.58 to -0.74, I2 = 0%) compared to placebo/SoC, based on moderate quality of evidence. HAT also reduced the duration of vasopressor use (MD -18.80 h, 95% CI: -23.67 to -13.93, I2 = 64%) compared to placebo/SoC, based on moderate quality of evidence. HAT increased hospital LOS (MD 2.05 days, 95% CI: 0.15-3.95, I2 = 57%) compared to placebo/SoC, based on very low quality of evidence. HAT did not increase incidence of adverse events compared to placebo/SoC. CONCLUSIONS: HAT appears beneficial in reducing vasopressor use and improving organ function in sepsis/septic shock patients. However, its advantages over hydrocortisone alone remain unclear. Future research should use hydrocortisone comparators and distinguish between sepsis-specific and comorbidity- or care-withdrawal-related mortality.

Regulation of THI and PDC genes by Pdc2 in Nakaseomyces glabratus (Candida glabrata) is complex.

Thiamine (vitamin B1) is essential for glucose catabolism. In the yeast species Nakaseomyces glabratus (formerly Candida glabrata) and Saccharomyces cerevisiae, the transcription factor Pdc2 (with Thi3 and Thi2) upregulates pyruvate decarboxylase (PDC) genes and thiamine biosynthetic and acquisition (THI) genes during starvation. There have not been genome-wide analyses of Pdc2 binding. Previously, we identified small regions of Pdc2 regulated genes sufficient to confer thiamine regulation. Here, we performed deletion analyses on these regions. We observed that when the S. cerevisiae PDC5 promoter is introduced into N. glabratus, it is thiamine starvation inducible but does not require the Thi3 coregulator. The ScPDC5 promoter contains a 22 bp duplication with an AT-rich spacer between the two repeats, which are important for regulation. Loss of the first 22 bp element does not eliminate regulation, but the promoter becomes Thi3-dependent, suggesting cis architecture can generate a Thi3-independent, thiamine starvation inducible response. Whereas many THI promoters only have one copy of this element, addition of the first 22 bp element to a Thi3-dependent promoter confers Thi3-independence. Finally, we performed fluorescence anisotropy and ChIP-seq. Pdc2 and Thi3 bind to regions that share similarity to the 22 bp element in the ScPDC5 promoter and previously identified cis elements in N. glabratus promoters. Also, while Pdc2 binds to THI and PDC promoters, neither Pdc2 nor Thi3 appear to bind the evolutionarily new NgPMU3 promoter that is regulated by Pdc2. Further study is warranted because PMU3 is required for cells to acquire thiamine from environments where thiamine is phosphorylated, such as in the human bloodstream.

Thiazolium salt mimics the non-coenzyme effects of vitamin B1 in rat synaptosomes.

Long-term studies have confirmed a causal relationship between the development of neurodegenerative processes and vitamin B1 (thiamine) deficiency. However, the biochemical mechanisms underlying the high neurotropic activity of thiamine are not fully understood. At the same time, there is increasing evidence that vitamin B1, in addition to its coenzyme functions, may have non-coenzyme activities that are particularly important for neurons. To elucidate which effects of vitamin B1 in neurons are due to its coenzyme function and which are due to its non-coenzyme activity, we conducted a comparative study of the effects of thiamine and its derivative, 3-decyloxycarbonylmethyl-5-(2-hydroxyethyl)-4-methyl-1,3-thiazolium chloride (DMHT), on selected processes in synaptosomes. The ability of DMHT to effectively compete with thiamine for binding to thiamine-binding sites on the plasma membrane of synaptosomes and to participate as a substrate in the thiamine pyrophosphokinase reaction was demonstrated. In experiments with rat brain synaptosomes, unidirectional effects of DMHT and thiamine on the activity of the pyruvate dehydrogenase complex (PDC) and on the incorporation of radiolabeled [2-14C]pyruvate into acetylcholine were demonstrated. The observed effects of thiamine and DMHT on the modulation of acetylcholine synthesis can be explained by suggesting that both compounds, which interact in cells with enzymes of thiamine metabolism, are phosphorylated and exert an inhibitory/activating effect (concentration-dependent) on PDC activity by affecting the regulatory enzymes of the complex. Such effects were not observed in the presence of structural analogs of thiamine and DMHT without a 2-hydroxyethyl substituent at position 5 of the thiazolium cycle. The effect of DMHT on the plasma membrane Ca-ATPase was similar to that of thiamine. At the same time, DMHT showed high cytostatic activity against neuroblastoma cells.

[B vitamins and diseases of the peripheral nervous system]. / Vitaminy gruppy B i zabolevaniya perifericheskoi nervnoi sistemy.

Various diseases of the peripheral nervous system are associated with metabolic disorders of B vitamins. A lack of neurotropic vitamins, which began in the early stages of the development of a bacterial disease, led to its more rapid development. The article analyzes data on B vitamin deficiency in the pathogenesis of the most dangerous diseases of the peripheral nervous system. Information is provided about the dangers of the clinical use of the drug Combilipen for the treatment of such patients.

Folic acid supplementation is associated with a decreased mortality and reduced hospital readmission in patients with decompensated alcohol-related liver cirrhosis.

BACKGROUND AND AIMS: Thiamine and folic acid malnutrition is highly frequent in patients with decompensated alcohol-related liver cirrhosis (aLC). Current guidelines therefore recommend vitamin supplementation in these patients. However, implementation and its impact on the clinical outcome remains unknown. Therefore, we aimed to analyze the use of thiamine and folic acid and their effects on mortality and morbidity in patients with decompensated aLC. METHODS: A number of 289 consecutive patients with decompensated aLC who received a paracentesis at Hannover Medical School between 2011 and 2023 were retrospectively investigated. The use of folic acid and thiamine-containing supplements was assessed in the discharge medication. Patients were followed for up to one year regarding liver transplant (LTx)-free survival and the incidence of hepatic encephalopathy, infections and hepatic decompensation requiring rehospitalization. RESULTS: Median baseline MELD was 15, median age 56.6 years. 73.0% (n = 211) were male patients. At hospital discharge, thiamine-containing supplements and folic acid were prescribed to 48.1% (n = 139) and 18.0% (n = 52) patients, respectively. Neither thiamine nor folic acid prescription were linked to improved clinical outcomes within 90 days. However, folic acid intake was associated with a higher one-year LTx-free survival (HR = 0.48; p = 0.04) in the multivariable analysis. Furthermore, folic acid substitution was linked to a decreased risk of rehospitalization within one year (HR = 0.55; p = 0.01) in the multivariable competing risk model. In contrast, thiamine prescription did neither affect LTx-free survival nor the here investigated liver-related complications. CONCLUSION: Folic acid, but not thiamine substitution was linked to an improved outcome in patients with decompensated aLC.