The restoration of hippocampal nerve de-myelination by methylcobalamin relates with the enzymatic regulation of homocysteine level in a rat model of moderate grade hepatic encephalopathy.

This article describes how methylcobalamin (MeCbl) restores nerve myelination in a moderate- grade hepatic encephalopathy (MoHE) model of ammonia neurotoxicity. The comparative profiles of myelin basic protein (MBP), homocysteine (Hcy) and methionine synthase (MS: a MeCbl- dependent enzyme) activity versus nerve myelination status were studied in the hippocampus of the control, the MoHE (developed by administering 100 mg/kg bw thioacetamide i.p. for 10 days) and the MoHE rats treated with MeCbl (500 µg/kg BW i.p.) for 7 days. Compared to those of control rats, the hippocampal CA1 and CA3 regions of the MoHE rats showed significantly lower myelinated areas and MBP immunostaining. This coincided with the deranged myelin layering in TEM images, decreased MBP protein and its transcript levels in hippocampus of MoHE rats. However, all these parameters recovered to normal levels after MeCbl treatment. MeCbl is a cofactor of MS that catalyzes the conversion of Hcy to methionine as a feeder step of methylation reactions. We observed significantly increased serum and hippocampal Hcy levels in MoHE rats, however, these levels were restored to control values with a concordant activation of MS due to MeCbl treatment. A significant recovery in neurobehavioral impairments in the MoHE rats due to MeCbl treatment was also observed. These findings suggest that MoHE pathogenesis is associated with deranged nerve myelination in the hippocampus and that MeCbl treatment is able to restore it mainly by activating MS, a MeCbl-dependent Hcy-metabolizing enzyme.

Combined effect of Neurotropin® and methylcobalamin on postherpetic neuralgia in mice infected with herpes simplex virus type-1.

BACKGROUND: Postherpetic pain (PHP) is difficult to control. Although Neurotropin® (NTP) and methylcobalamin (MCB) are often prescribed to treat the pain, the efficacy of combined treatment for PHP remains imcompletely understood. OBJECTIVE: In this study, we investigate the combined effects of NTP and MCB on PHP in mice. METHODS: NTP and MCB were administered from day 10-29 after herpes simplex virus type-1 (HSV-1) infection. The pain-related responses were evaluated using a paint brush. The expression of neuropathy-related factor (ATF3) and nerve repair factors (GAP-43 and SPRR1A) in the dorsal root ganglion (DRG) and neurons in the skin were evaluated by immunohistochemical staining. Nerve growth factor (NGF) and neurotrophin-3 (NT3) mRNA expression levels were evaluated using real-time PCR. RESULTS: Repeated treatment with NTP and MCB after the acute phase inhibited PHP. Combined treatment with these drugs inhibited PHP at an earlier stage than either treatment alone. In the DRG of HSV-1-infected mice, MCB, but not NTP, decreased the number of cells expressing ATF3 and increased the number of cells expressing GAP-43- and SPRR1A. In addition, MCB, but not NTP, also increased and recovered non-myelinated neurons decreased in the lesional skin. NTP increased the mRNA levels of NTF3 in keratinocytes, while MCB increased that of NGF in Schwann cells. CONCLUSION: These results suggest that combined treatment with NTP and MCB is useful for the treatment of PHP. The combined effect may be attributed to the different analgesic mechanisms of these drugs.

Efficacy of tokishakuyakusan and mecobalamin on post-infectious olfactory dysfunction: A prospective multicenter study.

OBJECTIVE: To determine if tokishakuyakusan (TSS) is effective for treating post-infectious olfactory dysfunction (PIOD) compared with vitamin B12 (mecobalamin). METHODS: We conducted a randomized, nonblinded clinical trial. Patients with PIOD enrolled in 17 hospitals and clinics from 2016 to 2020 were randomly divided into two groups, and we administered TSS or mecobalamin for 24 weeks. Their olfactory function was examined using interviews and T&T olfactometry. The improvement of olfactory dysfunction was assessed following the criteria of the Japanese Rhinologic Society. RESULTS: Overall, 82 patients with PIOD were enrolled in this study. In the TSS and mecobalamin groups, 39 patients completed the medication regimen. In the TSS and mecobalamin groups, olfactory dysfunction was significantly improved based on self-reports and olfactory test results. The improvement rate of olfactory dysfunction was 56% in the TSS group and 59% in the mecobalamin group. Early intervention within 3 months produced a better prognosis than the treatment initiated after 4 months. Furthermore, age and sex differences were not observed. Both medications produced no severe adverse events. CONCLUSION: The present study showed that TSS and mecobalamin might be useful for treating PIOD.

Aquacobalamin Accelerates Orange II Destruction by Peroxymonosulfate via the Transient Formation of Secocorrinoid: A Mechanistic Study.

Besides its use in medicine, vitamin B12 (cobalamin) and its derivatives have found in numerous applications as catalysts. However, studies related to the activation of oxidants via cobalamin are scant. In this work, we showed how the addition of aquacobalamin (H2OCbl) accelerates the destruction of azo-dye Orange II by peroxymonosulfate (HSO5-) in aqueous solutions. In neutral and weakly alkaline media, the process is initiated by the modification of the corrin macrocycle with HSO5-, which requires the preliminary deprotonation of the aqua-ligand in H2OCbl to give hydroxocobalamin, producing 5,6-dioxo-5,6-secocobalamin or its isomer (14,15-dioxo-14,15-secocobalamin). In acidic solutions, where the concentration of hydroxocobalamin is negligible, the formation of dioxo-seco-species is not observed, and the reaction between H2OCbl and HSO5- results in slow chromophore bleaching. Using terephthalic acid, we demonstrated the formation of hydroxyl radicals in the mixture of H2OCbl with HSO5-, whereas the generation of sulfate radicals was proved by comparing the effects of ethanol and nitrobenzene on Orange II destruction using the H2OCbl/HSO5- system. The reaction mechanism includes the binding of HSO5- to the Co(III) ion of dioxo-secocobalamin, which results in its deprotonation and the labilization of the O-O bond, leading to the formation of sulfate and hydroxyl radicals which further react with Orange II.

Effects of Infrared Combined with Methylcobalamin on the Vibratory Sensory Threshold and Nerve Conduction Velocity of the Lower Extremity in Patients with Diabetic Foot Treatment.

Objective: To investigate the effect of infrared combined with methylcobalamin on the vibratory sensory threshold and lower limb nerve conduction velocity of patients with diabetic foot. Methods: One hundred and six patients with diabetic foot in our hospital from February 2018 to December 2020 were enrolled and divided into the study and control groups. The patients in the control group were given methylcobalamin, and the patients in the research group were treated with infrared light on the basis of the control group. The therapeutic effect, vibration sensory threshold, lower limb nerve conduction velocity, and related biochemical index levels before and after treatment in the two groups were counted. Result: The total effective rate of the study group (94.34%) was significantly higher than that of the control group (81.13%). The left/right lower limb vibration sensation threshold decreased in both groups after treatment, and the study group was lower than that of the control group (P < 0.05). The conduction velocity of the left/right common peroneal nerve and tibial nerve increased in both groups after treatment, and the study group was larger than that of the control group (P < 0.05). The bFGF, VEGF, and APN increased in both groups after treatment. VEGF and APN increased and IL-6 and TNF-α decreased in both groups after treatment, and the study group was better than the control group (P < 0.05). Conclusion: Infrared and methylcobalamin combined treatment of diabetic foot can effectively improve lower extremity nerve conduction velocity and vibration sensory threshold, regulate serum bFGF and VEGF levels, reduce the degree of inflammatory response, and help improve the overall treatment effect.

The Utility of Oral Vitamin B1 and Mecobalamin to Improve Corneal Nerves in Dry Eye Disease: An In Vivo Confocal Microscopy Study.

Our purpose is to demonstrate the changes in cornea nerve parameters and symptoms and signs in dry eye disease (DED) patients after oral vitamin B1 and mecobalamin treatment. In this randomized double-blind controlled trial, DED patients were randomly assigned to either the treatment group (oral vitamin B1 and mecobalamin, artificial tears) or the control group (artificial tears). Corneal nerve parameters via in vivo confocal microscopy (IVCM), DED symptoms, and signs were assessed at baseline and 1 and 3 months post-treatment. In total, 398 eyes from 199 patients were included. In the treatment group, there were significant improvements in corneal nerve length, width, and neuromas, the sign of conjunctival congestion score (CCS), symptoms of dryness, pain, photophobia, blurred vision, total symptom score, and OSDI (OSDI) at 1/3 months post-treatment (all p < 0.05). Patients who received vitamin B1 and mecobalamin showed greater improvement in CCS, dryness scores at 1 month (p < 0.05), corneal fluorescein staining (CFS) (p = 0.012), photophobia (p = 0.032), total symptom scores (p = 0.041), and OSDI (p = 0.029) at 3 months. Greater continuous improvement in CFS (p = 0.045), dryness (p = 0.033), blurred vision (p = 0.031) and total symptom scores (p = 0.023) was demonstrated at 3 months than at 1 month post-treatment in the treatment group. We found that oral vitamin B1 and mecobalamin can improve corneal nerve length, width, reflectivity and the number of neuromas in IVCM, thereby repairing epithelial cells and alleviating some ocular symptoms. Thus, vitamin B1 and mecobalamin are potential treatment options for patients with DED.

Stability indicating RP-HPLC method for methylcobalamin determination in different dosage forms: Application to photodegradation kinetics and pH rate profiling.

A stability-indicating RP-HPLC method for methylcobalamin determination was developed. Stress degradation under variable conditions was carried out. Methylcobalamin had pronounced susceptibility to hydrolysis under acidic, alkaline, and photolytic conditions; further study of photolytic degradation kinetics and pH rate profiling over pH range 2-11 was carried out. Photodegradation of methylcobalamin followed zero-order kinetics with half-life 0.99 h equivalent to 1971.53 lux. Methylcobalamin followed pseudo-first-order kinetics upon exposure to acidic and alkaline hydrolysis with highest stability at pH 5 and least stability at pH 2. Optimization of chromatographic conditions was performed using two level full factorial design, and chromatographic analysis was executed using Inertsil column (250 × 4.6 mm, 5 µm) maintained at 25◦ C. Elution was carried out using 25 mM potassium dihydrogen phosphate (pH adjusted with phosphoric acid to 3.8): methanol:acetonitrile (55:35:10, v/v) as mobile phase. The flow rate was 1.0 ml/min. Detection was carried out at 220 nm using diode array detector. The method was validated as per ICH guidelines; the linearity was over concentration range 2-160 µg/ml with coefficient of determination 0.9995. The method was effectively applied for determination of methylcobalamin in Cobalvex ampoule, Cobal tablet, Cobal-F tablet, and Methyltechon oral dissolvable film without interfering from excipients within run time 6 min.

1H, 13C, and 15N resonance assignments and solution structures of the KH domain of human ribosome binding factor A, mtRbfA, involved in mitochondrial ribosome biogenesis.

Ribosome biogenesis is a complicated, multistage process coordinated by ribosome assembly factors. Ribosome binding factor A (RbfA) is a bacterial one, which possesses a single structural type-II KH domain. By this domain, RbfA binds to a 16S rRNA precursor in small ribosomal subunits to promote its 5'-end processing. The human RbfA homolog, mtRbfA, binds to 12S rRNAs in the mitoribosomal small subunits and promotes its critical maturation process, the dimethylation of two highly conserved consecutive adenines, which differs from that of RbfA. However, the structural basis of the mtRbfA-mediated maturation process is poorly understood. Herein, we report the 1H, 15N, and 13C resonance assignments of the KH domain of mtRbfA and its solution structure. The mtRbfA domain adopts essentially the same α1-ß1-ß2-α2(kinked)-ß3 topology as the type-II KH domain. Comparison with the RbfA counterpart showed structural differences in specific regions that function as a putative RNA-binding site. Particularly, the α2 helix of mtRbfA forms a single helix with a moderate kink at the Ser-Ala-Ala sequence, whereas the corresponding α2 helix of RbfA is interrupted by a distinct kink at the Ala-x-Gly sequence, characteristic of bacterial RbfA proteins, to adopt an α2-kink-α3 conformation. Additionally, the region linking α1 and ß1 differs considerably in the sequence and structure between RbfA and mtRbfA. These findings suggest some variations of the RNA-binding mode between them and provide a structural basis for mtRbfA function in mitoribosome biogenesis.

Diffusion Tensor Imaging Evaluates Effects of Acupoint Injection at Zusanli (ST36) for Type 2 Diabetic Peripheral Neuropathy.

BACKGROUND Acupoint injection is a therapeutic method that combines acupuncture and Western medicine and shows good curative effects for neuropathies. This study aimed to explore the efficacy of acupoint injection for treating diabetic peripheral neuropathy (DPN) by magnetic resonance neuroimaging (MRN). MATERIAL AND METHODS Forty patients with DPN were randomly divided into an acupoint injection group (AI; n=20) and intramuscular injection group (MI; n=20). The AI group received an acupoint injection of mecobalamin at acupoint Zusanli (S36); the MI group received intramuscular injection of mecobalamin. The curative effect was evaluated by the Toronto Clinical Neuropathy Score and diffusion tensor imaging (DTI). RESULTS The neuropathy scores of both groups decreased from baseline (AI 9.31±2.36; MI 9.34±2.54) to after the 2-week treatment (AI 7.12±1.87; MI 7.86±2.11); the differences were not significant. The fractional anisotropy (FA) value showed significant differences on the common peroneal nerve (AI 0.36±0.04; MI 0.31±0.05; P<0.05) and tibial nerve (AI 0.38±0.07; MI 0.34±0.06; P<0.05) after treatment. Likewise, apparent diffusion coefficient (ADC) values between groups showed significant differences for the common peroneal nerve (AI 1.44±0.17×10⁻³ mm²/s; MI 1.61±0.20×10⁻³ mm²/s; P<0.05) and tibial nerve (AI 1.54±0.22×10-3 mm²/s; MI 1.60±0.17 10⁻³ mm²/s; P<0.05). CONCLUSIONS Patients with DPN showed lower nerve FA and higher ADC in DTI-MRN. The acupoint injection of mecobalamin could treat DPN and repair the damaged nerves, which was shown by elevated FA and lowered ADC. Our study provides clinical evidence for the application of acupoint injection therapy and the evaluation of DPN by MRN.

Efficacy and Safety of Ultrahigh-Dose Methylcobalamin in Early-Stage Amyotrophic Lateral Sclerosis: A Randomized Clinical Trial.

Importance: The effectiveness of currently approved drugs for amyotrophic lateral sclerosis (ALS) is restricted; there is a need to develop further treatments. Initial studies have shown ultrahigh-dose methylcobalamin to be a promising agent. Objective: To validate the efficacy and safety of ultrahigh-dose methylcobalamin for patients with ALS enrolled within 1 year of onset. Design, Setting, and Participants: This was a multicenter, placebo-controlled, double-blind, randomized phase 3 clinical trial with a 12-week observation and 16-week randomized period, conducted from October 17, 2017, to September 30, 2019. Patients were recruited from 25 neurology centers in Japan; those with ALS diagnosed within 1 year of onset by the updated Awaji criteria were initially enrolled. Of those, patients fulfilling the following criteria after 12-week observation were eligible for randomization: 1- or 2-point decrease in the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) total score, a percent forced vital capacity greater than 60%, no history of noninvasive respiratory support and tracheostomy, and being ambulatory. The target participant number was 64 in both the methylcobalamin and placebo groups. Patients were randomly assigned through an electronic web-response system to methylcobalamin or placebo. Interventions: Intramuscular injection of methylcobalamin (50-mg dose) or placebo twice weekly for 16 weeks. Main Outcomes and Measures: The primary end point was change in ALSFRS-R total score from baseline to week 16 in the full analysis set. Results: A total of 130 patients (mean [SD] age, 61.0 [11.7] years; 74 men [56.9%]) were randomly assigned to methylcobalamin or placebo (65 each). A total of 129 patients were eligible for the full analysis set, and 126 completed the double-blind stage. Of these, 124 patients proceeded to the open-label extended period. The least square means difference in ALSFRS-R total score at week 16 of the randomized period was 1.97 points greater with methylcobalamin than placebo (-2.66 vs -4.63; 95% CI, 0.44-3.50; P = .01). The incidence of adverse events was similar between the 2 groups. Conclusions and Relevance: Results of this randomized clinical trial showed that ultrahigh-dose methylcobalamin was efficacious in slowing functional decline in patients with early-stage ALS and with moderate progression rate and was safe to use during the 16-week treatment period. Trial Registration: ClinicalTrials.gov Identifier: NCT03548311.

Improvement of the Clinical and Psychological Profile of Patients with Autism after Methylcobalamin Syrup Administration.

(1) Background: Autism, also known as autism-spectrum disorder, is a pervasive developmental disorder affecting social skills and psychological status in particular. The complex etiopathogenesis of autism limits efficient therapy, which leads to problems with the normal social integration of the individual and causes severe family distress. Injectable methylcobalamin was shown to improve the clinical status of patients via enhanced cell oxidative status and/or methylation capacity. Here we tested the efficiency of a syrup form of methylcobalamin in treating autism. (2) Methods: Methylcobalamin was administered daily at 500 µg dose to autistic children and young adults (n = 25) during a 200-day period. Clinical and psychological status was evaluated by parents and psychologists and plasma levels of reduced and oxidized glutathione, vitamin B12, homocysteine, and cysteine were determined before the treatment, and at day 100 and day 200 of the treatment. (3) Results: Good patient compliance was reported. Methylcobalamin treatment gradually improved the overall clinical and psychological status, with the highest impact in the social domain, followed by the cognitive, behavioral and communication characteristics. Changes in the clinical and psychological status were strongly associated with the changes in the level of reduced glutathione and reduced/oxidized glutathione ratio. (4) Conclusion: A high dose of methylcobalamin administered in syrup form ameliorates the clinical and psychological status of autistic individuals, probably due to the improved oxidative status.

The Potential Effects of a Compounded Methylcobalamin Nasal Spray on Short-term Memory Loss After Intracranial Hemorrhage: A Case Report.

Short-term memory loss is a common complication after intracranial hemorrhage or traumatic brain injury. FDA-approved cholinesterase inhibitors for memory symptoms of Alzheimer's disease have not been proven effective for improving memory impairment resulting from a hemorrhagic event. The purpose of this case study was to present the potential effectiveness of a compounded nasal spray containing methylcobalamin in improving short-term memory function in a patient post-intracranial hemorrhage. The patient started to administer the methylcobalamin nasal spray once daily after suffering from short-term memory loss for four years. His verbal memory, visual memory, and quality of life were assessed by the Hopkins Verbal Learning Test-Revised, Benton Visual Retention Test, and the 36-Item Short Form Survey, respectively, at baseline and 30 days after treatment. The delayed recall test was repeated after 60 days. After 30 days of treatment, the patient received improved scores in both verbal and visual memory tests, as well as improved self-reported quality of life. The patient became less dependent on phone reminders in daily life. The improvement in delayed recall remained significant after 60 days of treatment. This case report suggests a potentially safe and effective therapy for attenuating short-term memory impairment after intracranial hemorrhage.

Based on proteomics to explore the mechanism of mecobalamin promoting the repair of injured peripheral nerves.

Mecobalamin is commonly used in the adjuvant intervention of various peripheral nerve injuries. Actin cytoskeleton plays a role in the regeneration of myelin and axon. Therefore, the purpose of this study was to explore the possibility of mecobalamin regulating actin cytoskeleton in repairing nerve injury. In this study, a crush injury on the right sciatic nerve of two groups of rats (12 in each group) was established. The control group was only given normal saline (i.g.), and the intervention group was given mecobalamin 1 mg/kg (i.g.). The rats were sacrificed on 28th day and the injured nerves were collected for proteomics. The result shows that regulation of actin cytoskeleton pathway changed significantly. The expression of protein Vav1 was verified by Western blot and immunofluorescence. In the intervention group, the nerve fiber structure was complete, the axons were dense and symmetrical, and the myelin sheath was compact and uniform in thickness. The positive rate of myelin basic protein and ßⅢ-tubulin was higher than that in the control group. The findings of the study show that mecobalamin regulates the actin cytoskeleton in the repair of nerve damage and upregulates Vav1 in the regulation of actin cytoskeleton pathway.

Methylcobalamin Alleviates Neuronal Apoptosis and Cognitive Decline Induced by PM2.5 Exposure in Mice.

BACKGROUND: Fine particulate matter (particulate matter 2.5, PM2.5) is considered one of the harmful factors to neuronal functions. Apoptosis is one of the mechanisms of neuronal injury induced by PM2.5. Methylcobalamine (MeCbl) has been shown to have anti-apoptotic and neuroprotective effects. OBJECTIVE: The current work tried to explore the neuroprotective effects and mechanisms that MeCbl protects mice against cognitive impairment and neuronal apoptosis induced by chronic real-time PM2.5 exposure. METHODS: Twenty-four 6-week-old male C57BL/6 mice were exposed to ambient PM2.5 and fed with MeCbl for 6 months. Morris water maze was used to evaluate the changes of spatial learning and memory ability in mice. PC12 cells and primary hippocampal neurons were applied as the in vitro model. Cell viability, cellular reactive oxygen species (ROS) and the expressions of apoptosis-related proteins were examined. And cells were stained with JC-1 and mitochondrial membrane potential was evaluated. RESULTS: In C57BL/6 mice, MeCbl supplementation alleviated cognitive impairment and apoptosis-related protein expression induced by PM2.5 exposure. In in vitro cell model, MeCbl supplementation could effectively rescue the downregulation of cell viability induced by PM2.5, and inhibited the increased levels of ROS, cellular apoptosis, and the expressions of apoptosis related proteins related to PM2.5 treatment, which may be associated with modulation of mitochondrial function. CONCLUSION: MeCbl treatment alleviated cognitive impairment and neuronal apoptosis induced by PM2.5 both in vivo and in vitro. The mechanism for the neuroprotective effects of MeCbl may at least be partially dependent on the regulation of mitochondrial apoptosis.

Efficacy and safety of mecobalamin combined with vestibular rehabilitation training for acute vestibular neuritis: a systematic review and meta-analysis.

BACKGROUND: This study aimed to investigate the efficacy and safety of mecobalamin combined with vestibular rehabilitation training in acute vestibular neuritis and to improve the clinical therapeutic effect in vestibular nerve disease. METHODS: We performed a literature search of the PubMed, Medline, China National Knowledge Infrastructure (CNKI), and other databases from the date of establishment of the database until the present. The search terms included "mecobalamin", "vestibular rehabilitation training", "vestibular rehabilitation therapy", and "vestibular neuritis". References of the comparative study of vestibular rehabilitation training and vestibular rehabilitation training combined with mecobalamin were screened. Boolean logic retrieval was adopted, and Review Manager software was employed. RESULTS: Meta-analysis was conducted on a total of four studies with a low risk of bias. The activities specific balance confidence scale (ABC) scores of the two groups were heterogeneous (Chi2=8.56, I2=88%, P=0.003), and a fixed-effect model (FEM) analysis indicated that there were no significant differences in the ABC between the groups after treatment (Z=0.67, P=0.50). It may be that mecobalamin combined with vestibular rehabilitation training effectively alleviated the symptoms of vestibular neuritis in the experimental group, thereby reducing the canal paresis (CP) value. In addition, there was no heterogeneous dizziness handicap inventory (DHI) between the groups after treatment (Chi2=20.75, I2=86%, P=0.0001); finite element method (FEM) analysis showed that the DHI of the experimental group after 6 months of treatment was notably lower compared to that of the control group (Z=3.20, P=0.001). DISCUSSION: Mecobalamin combined with vestibular rehabilitation training can effectively improve vertigo and other symptoms of acute vestibular neuritis patients, with high effectiveness and safety.

Aerobic photolysis of methylcobalamin: unraveling the photoreaction mechanism.

The photo-reactivity of cobalamins (Cbls) is influenced by the nature of axial ligands and the cofactor's environment. While the biologically active forms of Cbls with alkyl axial ligands, such as methylcobalamin (MeCbl) and adenosylcobalamin (AdoCbl), are considered to be photolytically active, in contrast, the non-alkyl Cbls are photostable. In addition to these, the photolytic properties of Cbls can also be modulated in the presence of molecular oxygen, i.e., under aerobic conditions. Herein, the photoreaction of the MeCbl in the presence of oxygen has been explored using density functional theory (DFT) and time-dependent DFT (TD-DFT). The first stage of the aerobic photoreaction is the activation of the Co-C bond and the formation of the ligand field (LF) electronic state through the displacement of axial bonds. Once the photoreaction reaches the LF excited state, three processes can occur: namely the formation of OO-CH3 through the reaction of CH3 with molecular oxygen, de-activation of the {Im⋯[CoII(corrin)]⋯CH3}+ sub-system from the LF electronic state by changing the electronic configuration from (dyz)1(dz2)2 to (dyz)2(dz2)1 and the formation of the deactivation complex (DC) complex via the recombination of OO-CH3 species with the de-excited [CoII(corrin)] system. In the proposed mechanism, the deactivation of the [CoII(corrin)] subsystem may coexist with the formation of OO-CH3, followed by immediate relaxation of the subsystems in the ground state. Moreover, the formation of the OO-CH3 species followed by the formation of the {[CoIII(corrin)]-OO-CH3}+ complex stabilizes the system compared to the reactant complex.

Detection of partial and/or complete Y chromosome microdeletions of azoospermia factor a (AZFa) sub-region in infertile Iraqi patients with azoospermia and severe oligozoospermia.

BACKGROUND: This study aimed to analyze the incidence of azoospermia factor a (AZFa) microdeletions in the Y chromosome and their association with male infertility in a population with azoospermia and severe oligozoospermia from Iraq. METHODS: A total of 75 infertile Iraqi males and 25 healthy controls were included in this study. The semen analysis was performed to determine the azoospermia, severe oligozoospermia, or normal cases. The AZFa microdeletions were investigated using the real-time polymerase chain reaction (real-time PCR). Then, AZFa sub-region deletions were investigated by a conventional PCR. RESULTS: In total, 40 men with azoospermia and 35 men with severe oligozoospermia were selected. Out of 75 infertile males, 46 (61.3%) individuals had AZFa microdeletions, of whom 32 (69.6%) had partial deletion, while 14 (30.4%) males had complete deletion using real-time PCR. The frequency of microdeletions was significantly different between the infertile and control group (p-value < 0.00001). The proportion of AZFa microdeletions appeared higher in azoospermia men (72.5%, n = 29/40) than severe oligozoospermia men (48.6%, n = 17/35), but based on the conventional PCR results, only one azoospermia patient (2.2%) was shown to have complete AZFa deletion, while the other 45 patients (97.8%) had partial AZFa deletions. CONCLUSION: In this study, the partial AZFa microdeletions were more numerous than complete AZFa deletion. According to our results, the AZFa microdeletions might be associated with male infertility and spermatogenic failure. It is recommended to investigate the AZFa sub-region microdeletions in patients that shown AZFa microdeletions in primary screening.

Clinical Evaluation and Therapeutic Effects of Combination Treatment with Mecobalamin + Vitamin E in Recurrent Oral Ulcer.

PURPOSE: Recurrent oral ulcer is one of the most prevalent inflammatory ulcerative disorders of the oral mucosa. Due to the indeterminant cause and unpredictable course of the disease, clinical treatment of patients with recurrent oral ulcer is focused on relieving the pain, shortening the course of the disease, and prolonging the intermission period. Numerous chemical and biologic agents have been characterized as beneficial in the treatment of patients with recurrent oral ulcer, but there is currently no definitive therapy available. This study aimed to investigate the clinical effects and tolerability of combined mecobalamin tablets and vitamin E capsules in the treatment of recurrent oral ulcer. METHODS: A total of 58 patients with recurrent oral ulcer admitted to our hospital were allocated to receive mecobalamin tablets + vitamin E soft capsules (test group) or Fe complex enzyme gargle only (control group) (n = 29 per group). Changes in parameters such as pain level, as measured on a 10-point visual analog scale (VAS); ulcer status and number of ulcers; proinflammatory cytokine levels; and quality of life, as measured using SF-36, from before to after treatment were measured. Mean intermission time and mean ulcer healing time were calculated. Total effectiveness rate was also calculated. The occurrences of adverse reactions in the two groups were quantified. FINDINGS: The total intermission time interval was significantly longer, the mean ulcer healing time was considerably shorter, the total number of ulcers was appreciably less, and the total effectiveness rate was significantly greater in the test group compared to the control group (all, P < 0.05). The VAS scores were significantly greater after treatment than before treatment in both the test and control groups (mecobalamin + vitamin E, 2.16 [1.09] vs 7.87 [0.51]; control, 3.72 [1.15] vs 7.94 [0.56]; both, P < 0.05). Interleukin (IL)-8, tumor necrosis factor α, and C-reactive protein levels were appreciably down-regulated in both groups when compared to before treatment. In addition, IL-2 concentration and SF-36 scores were much greater after treatment in the test group with respect to the control group. Levels of IL-8, TNF-α, and CRP were significantly lesser in the test group than in the control group (all, P < 0.05). IMPLICATIONS: The combination of mecobalamin tablets and vitamin E soft capsules was effective in the treatment of recurrent oral ulcer. This combination can be used as an adjunctive therapy, offering effective pain control and improving quality of life in patients with oral ulcers.

A randomized comparative study of methylcobalamin, methylcobalamin plus pregabalin and methylcobalamin plus duloxetine in patients of painful diabetic neuropathy.

CONTEXT: Diabetic neuropathy affects 10.5%-32.2% of diabetic population posing clinical burden onto society. AIMS: We aimed to study the efficacy, safety, and tolerability of methylcobalamin, methylcobalamin plus pregabalin, and methylcobalamin plus duloxetine in patients of painful diabetic neuropathy. SETTINGS AND DESIGN: It is a prospective, randomized, open-label, interventional, and parallel-group study done in patients of painful diabetic neuropathy. MATERIALS AND METHODS: A total of 100 patients were recruited and randomized to three study groups A, B, and C on methylcobalamin, methylcobalamin and pregabalin, and methylcobalamin and duloxetine, respectively. Patients were assessed at day 0 and 4, 8, and 12 weeks. The tuning fork test, monofilament test, Thermal Sensitivity testing, and Visual Analog Scale (VAS) were used to analyze vibration, pressure, thermal sensitivity, and pain. STATISTICAL ANALYSIS USED: The results are expressed as mean ± standard deviation. Appropriate statistical methods were used to calculate P value (<0.05 - significant). RESULTS: The increase in number of patients with vibration perception is 11.6%, 37.9%, and 41.4%; pressure sensation is 7.6%, 37.9%, and 37.9%; and thermal sensitivity is 15.4%, 31.1%, and 37.9% in Groups A, B, and C, respectively. The decrease in VAS scores is 0.58 ± 0.14, 3.82 ± 0.05, and 4.17 ± 0.48 in Groups A, B, and C correspondingly. The adverse effects reported in Groups A, B, and C are 0%, 6.9%, and 10.3%, respectively. CONCLUSIONS: Group C is more efficacious when compared to Groups A and B while Group B is safer.

Methylcobalamin Protects Melanocytes from H2O2-Induced Oxidative Stress by Activating the Nrf2/HO-1 Pathway.

PURPOSE: Oxidative stress is considered a major determinant in the pathogenesis of vitiligo. Methylcobalamin (MeCbl) is an activated form of vitamin B12 that regulates inflammatory factors, counters oxidative stress, and reduces apoptosis in many disease models. However, the specific mechanism of MeCbl repigmentation against vitiligo is unknown. In this study, we explored the effect of MeCbl on melanocytes following hydrogen peroxide (H2O2)-induced oxidative stress. METHODS: We established an oxidative stress model using the immortalized human normal melanocyte cell line PIG1. We used a Cell Counting Kit-8 (CCK-8) to detect drug cytotoxicity, and we measured the melanin content of cells using the NaOH method. Intracellular oxidative damage was assessed by flow cytometry and antioxidant enzyme detection kits. In addition, we assessed the presence of apoptosis by flow cytometry and Western blots. We explored the underlying mechanisms of MeCbl during oxidative stress in melanocytes by analyzing the results of experiments based on real-time quantitative polymerase chain reaction (RT-qPCR), Western blotting, and laser scanning confocal immunofluorescence microscopy. Finally, we repeated the experiments after applying an inhibitor to block the Nrf2 pathway. RESULTS: We found that MeCbl treatment enhanced cell viability, increased melanin content, reduced intracellular reactive oxygen species (ROS) accumulation, increased the activities of antioxidant enzyme superoxide dismutase (SOD) and catalase (CAT), reduced melanocyte apoptosis, and up-regulated the expression of the Nrf2/HO-1 pathway. Moreover, the protective effects of MeCbl were significantly weakened after inhibiting the Nrf2/HO-1 pathway. CONCLUSION: Our results indicate that MeCbl attenuated the H2O2-induced oxidative stress in melanocytes by activating the Nrf2/HO-1 pathway, this suggests that MeCbl may be an effective treatment against vitiligo.