Effects of biotin and coated cobalamin on lactation performance, nutrient digestion and rumen fermentation in Holstein dairy cows.

Biotin (BI) and cobalamin (CA) are essential for rumen propionate production and hepatic gluconeogenesis. The study evaluated the influence of BI or/and coated CA (CCA) on milk performance and nutrient digestion in cows. Sixty Holstein dairy cows were assigned in a 2 × 2 factorial arrangement and randomised block design to four groups. The factors were BI at 0 or 20 mg/day and CCA at 0 or 9 mg CA/day. Dry matter intake increased with BI addition but was unchanged with CCA supply. Addition of BI or CCA increased fat-corrected milk, milk fat and milk protein yields and feed efficiency. Moreover, lactose yield was increased by CCA addition. Dry matter, organic matter, crude protein and acid detergent fibre total-tract digestibility increased for BI or CCA supply. When CCA was supplemented, positive response of neutral detergent fibre digestibility to BI addition was enhanced. Supplementing BI did not affect pH, propionate content and acetate to propionate ratio, but increased total volatile fatty acids (VFA) and acetate contents. Supplementing CCA decreased pH and acetate to propionate ratio, but increased total VFA, acetate and propionate contents. Rumen protease and carboxymethyl-cellulase activities and fungi, bacteria and Butyrivibrio fibrisolvens numbers increased for BI or CCA supply. In addition, protozoa increased for BI addition, and protease activity and Prevotella ruminicola increased for CCA supply. When CCA was supplemented, positive responses of R. albus and Ruminobacter amylophilus numbers to BI addition were enhanced. Blood glucose concentration was unchanged with BI supply, but increased for CCA supply. Blood nonesterified fatty acids and ß-hydroxybutyrate contents reduced with BI or CCA supply. Supplementation with BI or CCA increased blood BI or CA content. The results showed that supplementing BI or/and CCA improved lactation performance and nutrient digestion, and CCA supply did not enhance the lactation performance response to BI supply.

The biotin interference within interference suppressed immunoassays.

BACKGROUND: Reports of false laboratory findings due to a biotin supplementation have raised concerns about the safety of immunoassays. According to current research, biotin is known to cause interference in immunoassays. Since up to 70% of medical decisions are based on laboratory results and the significantly increased intake of biotin supplements in the recent years, the reliability of immunoassays is essential. METHODS: To evaluate this reliability two experiments were conducted. In the first experiment 59 interference suppressed immunoassays of the manufacturer Roche Diagnostics were examined regarding their sensitivity to a biotin interference. In the second experiment the pharmacokinetic of biotin was examined by supplementing volunteers with biotin. RESULTS: A combination of the results of both experiments suggests that a biotin interference in laboratory findings is probable. Contrary to the current state of research on sandwich immunoassays, falsely elevated test results occur more frequently than falsely low results. CONCLUSION: The interference suppressed immunoassays have shown in the experiment that they are susceptible to a biotin interference. Therefore, laboratory institutions, medical staff and patients must be aware of the possibility of a biotin interference. As a result, Roche Diagnostics may consider reviewing the interference suppression and their indications of the tests.

Effects of magnesium biotinate supplementation on serum insulin, glucose and lipid parameters along with liver protein levels of lipid metabolism in rats.

The objective of this study was to investigate the effects of a novel form of biotin (magnesium biotinate) on serum glucose, lipid profile, and hepatic lipid metabolism-related protein levels in rats. Forty-two rats were divided into six groups and fed a standard diet-based egg white powdered diet supplemented with either d-biotin at 0.01, 1, or 100 mg/kg BW or magnesium biotinate at 0.01, 1, or 100 mg/kg BW for 35 days. Neither form of biotin influenced (p > 0.05) serum glucose or insulin concentrations. Serum total cholesterol and triglyceride decreased with biotin from both sources (p < 0.05). Concentrations were lower with magnesium biotinate when comparing the 1 mg/kg dose (p < 0.05). Serum, liver, and brain biotin and liver cyclic guanosine monophosphate (cGMP) concentrations were greater when rats were treated with magnesium biotinate versus d-biotin, particularly when comparing the 1 and 100 mg/kg dose groups (p < 0.05). Both biotin forms decreased the liver SREBP-1c and FAS and increased AMPK-α1, ACC-1, ACC-2, PCC, and MCC levels (p < 0.05). The magnitudes of responses were more emphasized with magnesium biotinate. Magnesium biotinate, compared with a commercial d-biotin, is more effective in reducing serum lipid concentrations and regulating protein levels of lipid metabolism-related biomarkers.

Efficient induction of proximity-dependent labelling by biotin feeding in BMAL1-BioID knock-in mice.

Proximity-dependent biotin identification (BioID) is a useful method to identify unknown protein-protein interactions. Few reports have described genetically engineered knock-in mouse models for in vivo BioID. Thus, little is known about the proper method for biotin administration and which tissues are applicable. Here, we established a BioID knock-in mouse model of Brain and Muscle ARNT-Like 1 (BMAL1) and the BirA biotin ligase with R118G mutation (BirA*). The BMAL1-BioID mouse model was used to investigate the effect of biotin diet feeding on protein biotinylation in several tissues. The BMAL1-BirA* fusion protein-retained proper intracellular localization of BMAL1 and binding to CLOCK protein in HEK293T cells. A biotin labelling assay in mouse embryonic fibroblasts revealed the protein biotinylation activity of BMAL1-BirA* expressed in knock-in mouse cells depending on biotin supplementation. Lastly, feeding a 0.5% biotin diet for 7 days induced protein biotinylation in the brain, heart, testis and liver of BMAL1-BioID mice without adverse effects on spermatogenesis. In the kidney, the biotin diet increased biotinylated protein levels in BMAL1-BioID and control mice, suggesting the existence of endogenous biotinylation activity. These results provide valuable information to optimize the in vivo BioID procedure.

Toxicologic evaluation of a novel, highly soluble biotin salt, magnesium biotinate.

A novel, highly soluble biotin salt, magnesium biotinate (MgB), was assessed for general and genetic toxicity using several toxicologic tests. This battery of tests included in vitro bacterial reverse mutation test, in vitro mammalian micronucleus assay, and oral acute, 14-day, and 90-day repeat-dose toxicity in Sprague-Dawley (SD) rats. The results of the in vitro studies indicate that MgB is not mutagenic, clastogenic, or aneugenic. The acute oral toxicity study established an LD50 ≥ 5000 mg MgB/kg. In the 14-day oral toxicity study, doses of MgB up to 2500 mg MgB/kg/day produced no clinical signs or mortality. In the 90-day oral toxicity study, administration of 600 mg MgB/kg/day resulted in no clinical signs and was determined to be the no-observed-adverse-effect-level (NOAEL), which equates to 39 g biotin/day for a 70 kg human. Since MgB is composed of 93% biotin, the 600 mg NOAEL equates to approximately 1.3 million times the current recommended daily allowance of 30 µg biotin/day and 3900 times supplement levels of 10 mg biotin/day. Based on the toxicologic profile and lack of findings in various in vitro and in vivo studies, MgB may be considered safe for long-term human use.

Thiamine Treatment and Favorable Outcome in an Infant with Biallelic TPK1 Variants.

Episodic encephalopathy due to mutations in the thiamine pyrophosphokinase 1 (TPK1) gene is a rare autosomal recessive metabolic disorder. Patients reported so far have onset in early childhood of acute encephalopathic episodes, which result in a progressive neurologic dysfunction including ataxia, dystonia, and spasticity. Here, we report the case of an infant with TPK1 deficiency (compound heterozygosity for two previously described pathogenic variants) presenting with two encephalopathic episodes and clinical stabilization under oral thiamine and biotin supplementation. In contrast to other reported cases, our patient showed an almost normal psychomotor development, which might be due to an early diagnosis and subsequent therapy.

Mineral composition and microstructure of the abaxial hoof wall in dairy heifers after biotin supplementation.

The aim of this study was to evaluate the effect of daily biotin supplementation on the mineral composition and microstructure of the abaxial hoof wall in dairy heifers. The heifers were housed on a concrete floor and fed for weight gain more than 800 g per day, which is a challenging environment for the hoof. Twelve crossbred dairy heifers (Jersey × Holstein) were divided into two treatment groups. Animals in the control group (n = 6) received a diet without supplemental biotin, while the heifers in the biotin-supplemented feed group (n = 6) each received 20 mg of biotin daily for 120 days. Samples of the abaxial hoof wall were collected from the outer claw of the fore and hind limb, before and after supplementation. The samples were evaluated by X-ray fluorescence spectrometry, computed microtomography, atomic force microscopy and confocal laser scanning microscopy. Biotin supplementation increased the sulphur content and decreased the calcium and potassium content in the abaxial hoof wall. Biotin treatment also increased the percentage of horn tubules with smaller diameter marrow (17-51 µm). However, biotin did not influence the surface relief of the hoof wall, suggesting that its action is limited to the inner layers of the stratum corneum. Daily supplementation with 20 mg of biotin promoted changes in the mineral composition and microstructure of abaxial hoof wall of crossbred dairy heifers. These findings suggest biotin supplementation improves hoof quality and may help to understand the function of biotin in the stratum corneum.

Cell type-selective secretome profiling in vivo.

Secreted polypeptides are a fundamental axis of intercellular and endocrine communication. However, a global understanding of the composition and dynamics of cellular secretomes in intact mammalian organisms has been lacking. Here, we introduce a proximity biotinylation strategy that enables labeling, detection and enrichment of secreted polypeptides in a cell type-selective manner in mice. We generate a proteomic atlas of hepatocyte, myocyte, pericyte and myeloid cell secretomes by direct purification of biotinylated secreted proteins from blood plasma. Our secretome dataset validates known cell type-protein pairs, reveals secreted polypeptides that distinguish between cell types and identifies new cellular sources for classical plasma proteins. Lastly, we uncover a dynamic and previously undescribed nutrient-dependent reprogramming of the hepatocyte secretome characterized by the increased unconventional secretion of the cytosolic enzyme betaine-homocysteine S-methyltransferase (BHMT). This secretome profiling strategy enables dynamic and cell type-specific dissection of the plasma proteome and the secreted polypeptides that mediate intercellular signaling.

Relapses in Patients Treated with High-Dose Biotin for Progressive Multiple Sclerosis.

High-dose biotin (HDB) is a therapy used in non-active progressive multiple sclerosis (PMS). Several reports have suggested that HDB treatment may be associated with an increased risk of relapse. We aimed to determine whether HDB increases the risk of clinical relapse in PMS and describe the characteristics of the patients who experience it. We conducted a French, multicenter, retrospective study, comparing a group of PMS patients treated with HDB to a matched control group. Poisson regression was applied to model the specific statistical distribution of the annualized relapse rate (ARR). A propensity score (PS), based on the inverse probability of treatment weighting (IPTW), was used to adjust for indication bias and included the following variables: gender, primary PMS or not, age, EDSS, time since the last relapse, and co-prescription of a DMT. Two thousand six hundred twenty-eight patients treated with HDB and 654 controls were analyzed with a follow-up of 17 ± 8 months. Among them, 148 validated relapses were observed in the group treated with biotin and 38 in the control group (p = 0.62). After adjustment based on the PS, the ARR was 0.044 ± 0.23 for the biotin-treated group and 0.028 ± 0.16 for the control group (p = 0.18). The more relapses there were before biotin, the higher the risk of relapse during treatment, independently from the use of HDB. While the number of relapses reported for patients with no previous inflammatory activity receiving biotin has gradually increased, the present retrospective study is adequately powered to exclude an elevated risk of relapse for patients with PMS treated with HDB.

Safety and efficacy of MD1003 (high-dose biotin) in patients with progressive multiple sclerosis (SPI2): a randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: There is an unmet need to develop therapeutic interventions directed at the neurodegeneration that underlies progression in multiple sclerosis. High-dose, pharmaceutical-grade biotin (MD1003) might enhance neuronal and oligodendrocyte energetics, resulting in improved cell function, repair, or survival. The MS-SPI randomised, double-blind, placebo-controlled study found that MD1003 improved disability outcomes over 12 months in patients with progressive multiple sclerosis. The SPI2 study was designed to assess the safety and efficacy of MD1003 in progressive forms of multiple sclerosis in a larger, more representative patient cohort. METHODS: SPI2 was a randomised, double-blind, parallel-group, placebo-controlled trial done at 90 academic and community multiple sclerosis clinics across 13 countries. Patients were aged 18-65 years, had a diagnosis of primary or secondary progressive multiple sclerosis fulfilling the revised International Panel criteria and Lublin criteria, a Kurtzke pyramidal functional subscore of at least 2 (defined as minimal disability), an expanded disability status scale (EDSS) score of 3·5-6·5, a timed 25-foot walk (TW25) of less than 40 s, evidence of clinical disability progression, and no relapses in the 2 years before enrolment. Concomitant disease-modifying therapies were allowed. Patients were randomly assigned (1:1) by an independent statistician using an interactive web response system, with stratification by study site and disease history, to receive MD1003 (oral biotin 100 mg three times daily) or placebo. Participants, investigators, and assessors were masked to treatment assignment. The primary endpoint was a composite of the proportion of participants with confirmed improvement in EDSS or TW25 at month 12, confirmed at month 15, versus baseline. The primary endpoint was assessed in the intention-to-treat analysis set, after all participants completed the month 15 visit. Safety analyses included all participants who received at least one dose of MD1003. This trial is registered with ClinicalTrials.gov (NCT02936037) and the EudraCT database (2016-000700-29). FINDINGS: From Feb 22, 2017, to June 8, 2018, 642 participants were randomly assigned MD1003 (n=326) or placebo (n=316). The double-blind, placebo-controlled phase of the study ended when the primary endpoint for the last-entered participant was assessed on Nov 15, 2019. The mean time in the placebo-controlled phase was 20·1 months (SD 5·3; range 15-27). For the primary outcome, 39 (12%) of 326 patients in the MD1003 group compared with 29 (9%) of 316 in the placebo group improved at month 12, with confirmation at month 15 (odds ratio 1·35 [95% CI 0·81-2·26]). Treatment-emergent adverse events occurred in 277 (84%) of 331 participants in the MD1003 group and in 264 (85%) of 311 in the placebo group. 87 (26%) of 331 participants in the MD1003 group and 82 (26%) of 311 participants in the placebo group had at least one serious treatment-emergent adverse event. One (<1%) person died in the MD1003 group and there were no deaths in the placebo group. Despite use of mitigation strategies, MD1003 led to inaccurate laboratory results for tests using biotinylated antibodies. INTERPRETATION: This study showed that MD1003 did not significantly improve disability or walking speed in patients with progressive multiple sclerosis and thus, in addition to the potential of MD1003 for deleterious health consequences from interference of laboratory tests, MD1003 cannot be recommended for treatment of progressive multiple sclerosis. FUNDING: MedDay Pharmaceuticals.

Relapses During High-Dose Biotin Treatment in Progressive Multiple Sclerosis: a Case-Crossover and Propensity Score-Adjusted Prospective Cohort.

High-dose biotin (HDB) is a therapy used in non-active progressive multiple sclerosis (PMS). Some reports have suggested that HDB treatment may be associated with an increased risk of relapse. We evaluate the relationship between exposure to HDB for treating PMS and the risk of relapse. We screened for PMS patients prospectively registered in a French regional cohort being part of the OFSEP national registry. In a case-crossover design among patients who received HDB, we first compared number of relapses before and after initiation of HDB. Second, time to the first clinical relapse was compared between patients who received HDB (biotin group) and a control group using a Cox survival analysis after a propensity score (PS) matching (1:1) and inverse probability of treatment weighting (IPTW) method. In the 42 PMS patients who received HDB, the number of relapses was statistically and clinically significant higher after biotin initiation than before biotin initiation (incident rate ratio [IRR] 7.4, 95% confidence interval [CI] 3.5-15.9, p < 0.0001). With the PS matching method, the risk of relapse was significantly higher in the biotin group compared to the control group (hazard ratio [HR] 4.3, 95% CI 1.4-13.3, p = 0.01). The IPTW method with 440 control patients revealed consistent results (HR 5.1, 95% CI 2.3-11.3, p < 0.0001). In our non-randomized study, HDB treatment for PMS was associated with an increased risk of relapse. The follow-up of PMS patients initiating HDB should include careful assessment of clinical and radiological activity to monitor the potential pro-inflammatory effect of biotin.

Prevalence of detectable biotin in The Netherlands in relation to risk on immunoassay interference.

Despite the increasing awareness about biotin interference with immunoassays, so far, only two studies have quantified the prevalence of elevated biotin in patient populations. In a US study, over 7% had biotin concentrations exceeding 10 ng/mL, whereas in an Australian study only 0.8% of ED samples contained biotin exceeding 10 ng/mL. At present, representative data for the European population are lacking. In this study, we investigated biotin prevalence in The Netherlands in a representative cohort of routine laboratory requests in our laboratory using an LC-MS/MS assay for quantification of biotin in human plasma. In our study, we found 0.2% of samples exceeding 10 ng/mL of biotin, a finding more or less in line with the Australian data. Even though the biotin prevalence appears to be low, with concomitant low to moderate biotin concentrations, it is by no means a rare phenomenon. Laboratories like ours are likely to experience biotin positive samples on a daily basis with variable impact on patient care depending on the analytical bias from the immunoassay platform used. Our simple and robust LC-MS/MS assay for quantification of biotin in human samples may contribute to better understanding of the systemic concentrations seen after moderate- and high-dose biotin supplementation and the extent of immunoassay interference.

When thyroid labs do not add up, physicians should ask patients about biotin supplements.

A 69-year-old woman with a remote history of Graves' disease treated with radioactive iodine ablation, who was maintained on a stable dose of levothyroxine for 15 years, presented with abnormal and fluctuating thyroid function tests which were confusing. After extensive evaluation, no diagnosis could be made, and it became difficult to optimise the levothyroxine dose, until we became aware of the recently recognised biotin-induced lab interference. It was then noticed that her medication list included biotin 10 mg two times per day. After holding the biotin and repeating the thyroid function tests, the labs made more sense, and the patient was easily made euthyroid with appropriate dose adjustment. We also investigated our own laboratory, and identified the thyroid labs that are performed with biotin-containing assays and developed strategies to increase the awareness about this lab artefact in our clinics.

Assessment of biotin interference in thyroid function tests.

The aim of the study was to systematically characterize the interference of biotin on thyroid function tests and biotin washout periods.Ten healthy adults were recruited with administration of 5 and 10 mg/d biotin for 7 days. Analyte concentrations of thyroid function tests were measured at baseline prior to starting biotin and from 2 hours to 2 days after withdrawal of 5 and 10 mg/d biotin. The outcomes were compared the baseline with the several points after taking biotin at Roche cobas e602, Beckman UniCel DxI 800, and Abbott Architect 2000 immunoassay platforms, respectively.Ingesting 5 or 10 mg/d of biotin for 7 days could produce positive or negative interference among the thyroid function tests at Roche cobas e602 and Beckman UniCel DxI 800 systems, but no interference on Abbott Architect 2000. Interference duration of 5 mg/d biotin for Roche cobas e602 and Beckman UniCel DxI 800 of thyroid function tests lasted for 8 hours, while 10 mg/d biotin interfered with Roche cobas e602 or Beckman UniCel DxI 800 for 1 day or 2 days.This study provides valuable guidance on biotin washout periods at doses common in over-the-counter supplements necessary to avoid false assay results.Trial registration: ChiCTR1800020472.

A strategy for iron oxide nanoparticles to adhere to the neuronal membrane in the substantia nigra of mice.

Effective attachment of magnetic nanoparticles to neuronal membranes has far-reaching significance in activating ion channels and treating neurodegenerative diseases. Superparamagnetic iron oxide nanoparticles (SPIONs) synthesized by the polyol pyrolysis method have the advantages of rich surface functional groups, excellent magnetic properties, controllable particle size and water dispersibility. We propose that perfusion of biotin into the targeted brain area should be initially performed because it tends to be adsorbed by cell membranes, followed by injection of streptavidin (SA)-modified SPIONs into the same area of the brain. By means of the strong binding force between SA and biotin, the SPIONs may subsequently adhere to the cell surfaces in the brain area. In this work, fluorescein isothiocyanate-streptavidin (FITC-SA) was modified on the surface of polyethylene imine (PEI)-SPIONs by the EDC-NHS method and stereotaxically injected into the biotin-supplemented substantia nigra of mice. The combination of fluorescence detection with transmission electron microscopy (TEM) confirmed that FITC-SA/PEI-SPIONs adhered to neuronal membranes in the substantia nigra of mice 24 h after injection. The results show that our strategy can promote the attachment of SPIONs to neuronal membranes.

[Intake of high dose biotin: A cause of artificial hyperthyroidism]. / La prise de biotine à fortes doses : une cause d'hyperthyroïdie biologique factice.

INTRODUCTION: Many hormone immunoassays use the biotin streptavidin interaction to immobilize immune complexes. The intake of high dose biotin can interfere with immunoassays using the biotin streptavidin interaction. The biotin-immunoassay interference generates falsely low or falsely high tests of hormones according to the type of immunoassay used. CASE REPORT: A 70-year-old patient, with progressive multiple sclerosis, was referred to our hospital for thyrotoxicosis. She was found to have markedly elevated thyroid hormones level (T3-T4) and decreased thyrotropin (TSH) level but she had no symptoms of hyperthyroidism. An ingestion of biotin, that is more and more frequent in patients with progressive multiple sclerosis, was found. Thyroid function tests normalized after discontinuation of biotin treatment. CONCLUSION: The discrepancy between a clinical exam which is not indicative of thyrotoxicosis and markedly abnormal thyroid function tests should lead to a search for biotin intake, which can interfere with thyroid function tests.