vitamin-b-12 and Ischemia

Topics: Enterostomy; Fluid Therapy; Humans; Intestinal Absorption; Intestine, Small; Ischemia; Malnutrition; Nutritional Support; Short Bowel Syndrome; Vitamin B 12

Hyperhomocysteinemia has been identified as a risk factor for venous and arterial thrombosis especially in adult populations. Twenty-eight patients with an initial diagnosis of ischemic stroke and 100 controls, aged

Topics: Adolescent; Child; Child, Preschool; Folic Acid; Homocysteine; Humans; Hyperhomocysteinemia; Infant; Ischemia; Male; Methylenetetrahydrofolate Reductase (NADPH2); Mutation, Missense; Polymorphism, Single Nucleotide; Retrospective Studies; Risk Factors; Stroke; Thailand; Thrombosis; Vitamin B 12

Cardiovascular diseases are the primary cause of mortality in France. Many epidemiological studies have shown that the total homocysteine concentration is a risk indicator for cardiovascular disease. Furthermore, it has been shown that the homocysteine concentration can be effectively lowered by supplementation with folic acid, vitamin B6 and B12. However, it is not yet known whether a reduction of the homocysteine concentration by such a supplementation indeed leads to a decreased risk of cardiovascular disease. Another possible dietary factor that may lower the risk of cardiovascular disease is fish-oil, which is rich in omega-3 fatty acids. These fatty acids lower platelet aggregation and triglyceride rich lipoproteins and may have antiarrhythmic effects. Some trials have investigated the effect of fish or fish-oil on cardiovascular mortality, and the results, although not conclusive, suggest a protective effect of a higher intake. In the SU.FOL.OM3 study we will evaluate the effect of supplementation at nutritional doses of folate (in the natural 5-methyl-tetrahydrofolate form) in combination with vitamin B6 and B12 and/or omega-3 fatty acids and/or placebo on recurrent ischemic diseases in a factorial design. The supplements will be randomly allocated to the participants in a double-blind fashion. In total 3,000 patients aged between 45 and 80 years who had a past history of myocardial infarction or unstable angina pectoris or an ischemic stroke will be included. The participants will be supplemented and followed up for a period of five years.

Topics: Aged; Aged, 80 and over; Coronary Artery Disease; Dietary Supplements; Double-Blind Method; Fatty Acids, Omega-3; Female; Folic Acid; Homocysteine; Humans; Intracranial Arteriosclerosis; Ischemia; Male; Middle Aged; Randomized Controlled Trials as Topic; Risk Factors; Secondary Prevention; Vitamin B 12; Vitamin B 6

Ovarian ischemia is a gynecological emergency case that occurs as a result of ovarian torsion. Oxidative stress and inflammation play central roles in the development of ischemia/reperfusion injuries. We investigated the effects of Vitamin B12, thought to possess antioxidant characteristics on oxidative stress and the toll-like receptor 4 (TLR-4)/nuclear factorkappa B (NF-κB) signaling pathway in the ovaries during ischemia-reperfusion. Forty-eight rats were randomly assigned into six groups and the groups are designed as follows: Control (C), Ischemia (I), Ischemia + Vitamin B12 (I + B12), Ischemia-Reperfusion (I/R), I/R + Vitamin B12 (I/R + B12) and Sham + Vitamin B12. Vitamin B12 was administered at a dose of 400 mcg/kg via the i.p. route once daily for three days before I/R procedure. Tissue interleukin-1β (IL-1β) and interleukin-6 (IL-6) and malondialdehyde (MDA) levels in ovarian tissue increased following I/R, while glutathione (GSH) levels decreased. Moreover, extensive congestion, edema, hemorrhage and defective follicle were observed. Both NF-κB and TLR-4 expression levels also increased in the group exposed to I/R. While GSH levels increased, IL-1β, IL-6, MDA, NF-κB and TLR-4 levels decreased with Vitamin B12 treatment. In addition, ovarian tissue without edema, mild congestion, and normal-appearing follicles were observed following Vitamin B12 administration. The findings showed that I/R in ovarian tissue resulted in significant tissue damage by increasing oxidative stress and inflammation. However, Vitamin B12 application was effective and alternative agent in reducing injury deriving from inflammation and oxidative stress developing in association with I/R in ovarian tissue.

Topics: Animals; Female; Glutathione; Inflammation; Interleukin-6; Ischemia; NF-kappa B; Ovary; Oxidative Stress; Rats; Rats, Wistar; Reperfusion Injury; Signal Transduction; Toll-Like Receptor 4; Vitamin B 12

Stroke remains the second leading cause of death world wide after ischaemic heart disease. Stroke occurs mainly due to infarction which accpounts for 85% of etiological factors and 15% due to hemorrhage. Hyperhomocysteinemia is associated with premature atherosclerosis and vascular events and it is an important risk factor for cerebrovascular accidents.. Case will be selected from patients admitted to medical wards in Navodaya Medical College, Raichur. Duration based study with a minimum of 50 cases for a period of 18 months from august 2019. In all patients admitted with symptoms suggestive of stroke careful methodical examination of central nervous system carried out recording all physical signs in order. In all cases with the help of close relatives the preceding symptoms and risk factors were enquired all patients were subjected to CT scan brain, CBC, FBS, PPBS, lipid profile and serum homocysteine levels were done.. In our study we observed that the serum homocysteine levels were elevated in ischemic stroke significantly. The mean serum homocysteine levels were higher in non diabetics(29.57 micromole/ litre) than diabetics (20.75 micromole/litre) and difference was statistically significant (P<0.001). Mean serum Homocysteine levels were higher in age group <65 years(28.73 micromole/litre) than patient age >65 years (20.50 micromole/litre) and the difference was statistically significant (p<0.001). Mean serum heomocysteine levels were higher in hypertensives (26.73 micromole/litre) than normotensive (23.28 micromole/litre) however the difference was statistically not significant (p>0.001).The mean serum homocysteine levels were higher in patients with normal lipid profile(30.97 micromole/litre) than patients with dyslipidemia (21.92 micromole/litre) and the difference was statistically significant (p<0.001).. The present study revealed that hyperhomocysteinemia appears to be an important risk factor for ischemic stroke. It is therefore important to use serum homocysteine as an important tool to investigate all cases of ischemic stroke and if serum homocysteine is elevated patient should be put on multivitamins containing vitamin B12, folic acid and pyridoxine to reduce serum homocysteine levels.

Topics: Aged; Homocysteine; Humans; Hyperhomocysteinemia; Ischemia; Ischemic Stroke; Lipids; Risk Factors; Stroke; Vitamin B 12

Renal ischemia/reperfusion injury (IRI) is a leading cause of acute kidney injury (AKI), a potentially fatal syndrome characterized by a rapid decline in kidney function. Excess production of superoxide contributes to the injury. We hypothesized that oral administration of a high dose of vitamin B12 (B12 - cyanocobalamin), which possesses a superoxide scavenging function, would protect kidneys against IRI and provide a safe means of treatment. Following unilateral renal IR surgery, C57BL/6J wild type (WT) mice were administered B12 via drinking water at a dose of 50 mg/L. After 5 days of the treatment, plasma B12 levels increased by 1.2-1.5x, and kidney B12 levels increased by 7-8x. IRI mice treated with B12 showed near normal renal function and morphology. Further, IRI-induced changes in RNA and protein markers of inflammation, fibrosis, apoptosis, and DNA damage response (DDR) were significantly attenuated by at least 50% compared to those in untreated mice. Moreover, the presence of B12 at 0.3 μM in the culture medium of mouse proximal tubular cells subjected to 3 hr of hypoxia followed by 1 hr of reperfusion in vitro showed similar protective effects, including increased cell viability and decreased reactive oxygen species (ROS) level. We conclude that a high dose of B12 protects against perfusion injury both in vivo and in vitro without observable adverse effects in mice and suggest that B12 merits evaluation as a treatment for I/R-mediated AKI in humans.

Topics: Acute Kidney Injury; Animals; Apoptosis; Ischemia; Kidney; Mice; Mice, Inbred C57BL; Reperfusion Injury; Superoxides; Vitamin B 12

To assess the outcome of patients with medically treated hyperhomocysteinemia (HHC) requiring intervention for critical limb ischemia (CLI).. A parallel observational study was conducted to compare the clinical and revascularization outcomes of CLI patients who received standardized treatment for HHC preoperatively (folic acid and vitamin B12) vs. contemporaneous patients with normal homocysteine levels. The threshold for HHC diagnosis was 13.0 μmol/L. From 2009 to 2011, 169 patients underwent revascularization procedures for CLI. Of these, all 66 patients (40 men; mean age 69.6 ± 11.2 years) with HHC (mean 17.3 μmol/L, range 13.5-34.9) were treated to normalize the homocysteine level prior to lower limb revascularization. The remaining 103 patients (58 men; mean age 72.7±8.1 years) had normal homocysteine levels (8.2 μmol/L, range 5-12.3) before revascularization. The primary endpoint was symptomatic and hemodynamic improvement in the treated HHC group. The secondary endpoints were all-cause survival, binary restenosis, reintervention, amputation-free survival, and major adverse events. The treated HHC cohort was compared to an age/sex-matched historical group of patients with untreated HHC from 2002 to 2006 before HHC pretreatment became routine. All interventions (endovascular, hybrid, and open) were performed by the same surgeon, and the groups were evenly matched.. Patients with HHC were treated for a mean 12.2 days, which significantly reduced their mean homocysteine level after 3 weeks to 10.1 μmol/L (range 6.2-14.4, p<0.05). After revascularization, immediate clinical improvement was similar between normal homocysteine and medically corrected HHC groups. There was no significant difference in time to binary restenosis (p=0.822). Secondary endpoints and all-cause mortality were similar. Multivariate logistic regression showed that untreated HHC was a significant factor for graft occlusion and limb loss (p<0.0001), but medically corrected HHC was no longer predictive of adverse operative outcome.. Patients with medically corrected HHC have similar outcomes compared to those with normal homocysteine levels. Thus, aggressively treating HHC with folic acid and vitamin B12 may help enhance the clinical outcome of CLI patients undergoing revascularization.

Topics: Aged; Aged, 80 and over; Amputation, Surgical; Biomarkers; Chi-Square Distribution; Critical Illness; Disease-Free Survival; Drug Therapy, Combination; Endovascular Procedures; Female; Folic Acid; Hemodynamics; Homocysteine; Humans; Hyperhomocysteinemia; Ischemia; Kaplan-Meier Estimate; Limb Salvage; Logistic Models; Lower Extremity; Male; Middle Aged; Multivariate Analysis; Odds Ratio; Risk Factors; Time Factors; Treatment Outcome; Vascular Patency; Vitamin B 12; Vitamin B Complex

Topics: Diabetes Complications; Diabetes Mellitus, Type 2; Disease Progression; Female; Humans; Insulin; Ischemia; Male; Metformin; Models, Biological; Models, Theoretical; Polycystic Ovary Syndrome; Prostatic Neoplasms; Vitamin B 12

Topics: Case-Control Studies; Creatinine; Folic Acid; Genotype; Glomerular Filtration Rate; Homocysteine; Humans; Hyperhomocysteinemia; Hypertension, Renal; Ischemia; Methylenetetrahydrofolate Reductase (NADPH2); Nephrons; Renal Artery Obstruction; Vitamin B 12

Hyperhomocysteinemia is a risk factor for ischemic stroke. Hypothyroidism may cause hyperhomocysteinemia. To date, no works have examined the association between hypothyroidism and hyperhomocysteinemia in ischemic stroke. We aimed to investigate the roles of hypothyroidism and hyperhomocysteinemia in ischemic stroke, and whether any relationship exists between hypothyroidism and hyperhomocysteinemia in ischemic stroke patients.. The study included 249 ischemic stroke patients and 102 patients with no history of stroke. Patients were evaluated for conventional risk factors and levels of homocysteine, thyroid-stimulating hormone, vitamin B12 and folic acid.. Ten (4%) patients in the ischemic stroke group had subclinical hypothyroidism. We did not find any overt or subclinical hypothyroidism in the control group. Hypothyroidism was higher to a statistically significant degree in the ischemic stroke group (p<0.05). Both hyperhomocysteinemia and hypothyroidism were associated with ischemic stroke patients. However, no association was found between hyperhomocysteinemia and hypothyroidism. Ischemic stroke patients with hypothyroidism had lower levels of HDL cholesterol and levels of total cholesterol/HDL-C and LDL-C/HDL-C were higher than those of ischemic stroke patients without hypothyroidism.. Hypothyroidism is associated with ischemic stroke. Low HDL cholesterol, high total cholesterol/HDL-C and high LDL-C/HDL-C were associated in ischemic stroke patients with hypothyroidism. Hyperhomocysteinemia was not found to be associated with ischemic stroke patients with hypothyroidism.

Topics: Aged; Dyslipidemias; Female; Folic Acid; Humans; Hyperhomocysteinemia; Immunoassay; Ischemia; Male; Middle Aged; Risk Factors; Statistics, Nonparametric; Thyrotropin; Turkey; Vitamin B 12

Topics: Aged; Aortic Aneurysm, Abdominal; Atherosclerosis; Carotid Artery Diseases; Folic Acid; Genotype; Homocysteine; Humans; Ischemia; Leg; Male; Methylenetetrahydrofolate Reductase (NADPH2); Peripheral Vascular Diseases; Risk Factors; Vitamin B 12

The Vitamin Intervention for Stroke Prevention trial (VISP) intention-to-treat analysis did not show efficacy of combined vitamin therapy for recurrent vascular events in patients with nondisabling stroke. Reasons for lack of efficacy may have included folate fortification of grain products, inclusion of the recommended daily intake for B12 in the low-dose arm, treatment with parenteral B12 in patients with low B12 levels in both study arms, a dose of B12 too low for patients with malabsorption, supplementation with nonstudy vitamins, and failure of patients with significant renal impairment to respond to vitamin therapy. We conducted an efficacy analysis limited to patients most likely to benefit from the treatment, based on hypotheses arising from evidence developed since VISP was initiated. The criteria for this subgroup were defined before any data analysis.. For this analysis, we excluded patients with low and very high B12 levels at baseline (<250 and >637 pmol/L, representing the 25th and 95th percentiles), to exclude those likely to have B12 malabsorption or to be taking B12 supplements outside the study and patients with significant renal impairment (glomerular filtration rate <46.18; the 10th percentile).. This subgroup represents 2155 patients (37% female), with a mean age of 66+/-10.7 years. For the combined end point of ischemic stroke, coronary disease, or death, there was a 21% reduction in the risk of events in the high-dose group compared with the low-dose group (unadjusted P=0.049; adjusted for age, sex, blood pressure, smoking, and B12 level P=0.056). In Kaplan-Meier survival analysis comparing 4 groups, patients with a baseline B12 level at the median or higher randomized to high-dose vitamin had the best overall outcome, and those with B12 less than the median assigned to low-dose vitamin had the worst (P=0.02 for combined stroke, death, and coronary events; P=0.03 for stroke and coronary events).. In the era of folate fortification, B12 plays a key role in vitamin therapy for total homocysteine. Higher doses of B12, and other treatments to lower total homocysteine may be needed for some patients.

Topics: Aged; Disease-Free Survival; Female; Folic Acid; Glomerular Filtration Rate; Homocysteine; Humans; Ischemia; Male; Middle Aged; Models, Statistical; Randomized Controlled Trials as Topic; Stroke; Time Factors; Treatment Outcome; Vitamin B 12; Vitamins

Hyperhomocysteinaemia has recently been identified as an important risk factor for atherosclerotic vascular disease. Screening for hyperhomocysteinaemia has been recommended, however, the incidence of hyperhomocysteinaemia in vascular patients is not known.. To determine the incidence of hyperhomocysteinaemia in vascular patients, to determine the relation of hyperhomocysteinaemia with folate, vitamin B12 levels and lipid profiles in vascular patients. To examine if there is a relationship between the degree of vascular injury and homocysteine concentration.. New vascular patients at The Queen Elizabeth Hospital were recruited and divided into peripheral, and aneurysmal presentations. Patients demographics were recorded, blood samples were taken for fasting lipid profile, and homocysteine concentration. Samples were also taken for vitamin B12, plasma and red cell folate levels. Sixty age and sex matched controls were included for comparison.. One hundred and twenty-six patients have been recruited, (95 men and 31 women) with a median age of 68 years (61-74 years). The incidence of elevated homocysteine, and cholesterol levels was 33, 47 and 24%. The levels of vitamin B12 and folate were normal in all patients. Homocysteine was elevated in 27% of claudicants, 50% of patients with rest pain and 53% of patients with an aortic aneurysm.. There is a high rate of hyperhomocysteinaemia in vascular patients with a higher incidence in patients with rest pain. There was also a high incidence of elevated homocysteine levels in patients with an abdominal aortic aneurysm. The rate of growth of these aneurysms is currently under review. Low folate or B12 concentrations is not the cause of raised homocysteine levels.

Topics: Aged; Aortic Aneurysm, Abdominal; Chronic Disease; Female; Folic Acid; Humans; Hyperhomocysteinemia; Intermittent Claudication; Ischemia; Leg; Lipids; Male; Middle Aged; Vascular Diseases; Vitamin B 12

Moderate hyperhomocysteinemia may be a risk factor for atherosclerotic peripheral vascular disease (PVD). In order to develop PVD at an early age risk factors are more strongly expressed and hyperhomocysteinemia may be one such factor. Homocysteine is derived from methionine and is metabolised by cystathionine-synthase to cystathionine or remethylated to methionine. Cystathionine-synthase activity is dependent on vitamin B6 while the remethylation of homocysteine is dependent on vitamin B12 and folate. The present study analyses homocysteine in patients operated on for lower extremity ischaemia before the age of 50. Homocysteine before and after loading with methionine, vitamin B6, B12 and folate were measured at follow-up. The patients were compared to age- and sex-matched controls. Significantly more patients than controls had hyperhomocysteinemia, 16/58 vs. 4/65, defined as fasting total homocysteine above 18.6 mumol/l. Loading with methionine did not further discriminate between patients and controls. Smoking patients had higher levels of homocysteine than non-smoking patients or smoking and non-smoking controls. Smoking patients also had lower levels of vitamin B6. When comparing patients with suprainguinal, infrainguinal and multilevel disease the highest homocysteine levels were seen in the latter group. Also, in this group smoking patients had higher homocysteine levels. Multivariate analysis revealed that homocysteine was associated with low levels of vitamin B12, folate and smoking. Smoking therefore seems to be connected to increased homocysteine levels in patients with early development of atherosclerosis, partly explained by decreased levels of B6, B12 and folate.

Topics: Adult; Arteriosclerosis; Female; Folic Acid; Follow-Up Studies; Homocysteine; Humans; Ischemia; Male; Methionine; Middle Aged; Postoperative Complications; Pyridoxine; Risk Factors; Smoking; Vitamin B 12

The brain oedema, distribution space (DS) and brain uptake index (BUI), of L-glucose, inulin, B12 vitamin and of three polypeptidic hormones of increasing molecular weight (angiotensin-I, gastrin and insulin) were measured in the rat after sham operation, porto-caval shunt (PCS) or liver ischaemia. At an early stage following PCS or liver ischaemia brain oedema was not constant, and was only demonstrable after liver ischaemia in a large number of animals. Substances without an active transport and with a low diffusion coefficient such as L-glucose and inulin had a very low BUI, unchanged even if the 3H2O brain content or the DS were modified. B12 vitamin, DS and BUI were very high and did not change after liver ischaemia or PCS. Insulin DS and BUI were low in the three groups of animals, whereas it decreased after PCS for gastrin. A significant increase of BUI and DS (without any cerebral oedema) was demonstrated for angiotensin-I, a polypeptidic hormone of molecular weight 1300. This polypeptidic marker is in the same range of MW as the preliminary recently recognized medium-sized molecules which may be involved in the pathogenesis of encephalopathy during experimental acute liver failure. However, not only the MW, but the nature of such polypeptides may be of importance in the genesis of this limited impairment of BBB permeability.

Topics: Acute Disease; Angiotensin I; Animals; Blood-Brain Barrier; Brain Edema; Ischemia; Liver; Male; Molecular Weight; Permeability; Portacaval Shunt, Surgical; Rats; Rats, Inbred Strains; Vitamin B 12

Permeability of the small intestinal mucosa was estimated using a perfusion technique after either a period of ischaemia or exposure to acetyl salicylate. It was shown that these procedures increased the passive permeability of the mucosa to macromolecules while maintaining normal mucosal selectivity. Histologically, there was derangment of the epithelial cell layer of the villous tips without damage to the epithelial basement membrane or subepithelial structures. It is concluded that the epithelial cell layer is purely limiting with no selective function and that the role of selectivity must be ascribed to either or both of the other mucosal barriers, the capillary and the epithelial basement membrane.

Topics: Animals; Aspirin; Basement Membrane; Cell Membrane Permeability; Creatinine; Female; Intestinal Mucosa; Intestine, Small; Inulin; Ischemia; Povidone; Rabbits; Urea; Vitamin B 12

Topics: Adolescent; Adrenocorticotropic Hormone; Adult; Aged; Anti-Bacterial Agents; Arteriosclerosis; Basilar Artery; Cerebrovascular Disorders; Chronic Disease; Deoxyribonucleases; Diabetic Neuropathies; Diuretics; Facial Nerve; Facial Paralysis; Female; Herpes Zoster; Humans; Hypertension; Ischemia; Male; Middle Aged; Physical Therapy Modalities; Prednisolone; Recurrence; Tonsillitis; Vertebral Artery; Vitamin B 12

Topics: Aged; Cholelithiasis; Crohn Disease; Diarrhea; Female; Gastrointestinal Agents; Humans; Ileum; Ischemia; Kidney Calculi; Lignin; Malabsorption Syndromes; Male; Mesentery; Middle Aged; Postoperative Complications; Preoperative Care; Vitamin A; Vitamin B 12; Vitamin D; Vitamin K

Topics: Animals; Cobalt Isotopes; Disease Models, Animal; Dogs; Intestinal Absorption; Intestinal Diseases; Intestinal Obstruction; Intestine, Small; Ischemia; Methods; Molecular Weight; Time Factors; Vitamin B 12

Topics: Adult; Amblyopia; Anemia, Pernicious; Child; Chloroquine; Craniocerebral Trauma; Cyanides; Female; Humans; Ischemia; Male; Methanol; Nerve Compression Syndromes; Optic Atrophy; Optic Chiasm; Optic Neuritis; Poisoning; Scotoma; Smoking; Syndrome; Syphilis; Vision Disorders; Vitamin B 12

Topics: Aged; Anemia, Pernicious; Autoantibodies; Body Height; Body Weight; Female; Fluorescent Antibody Technique; Gastric Acidity Determination; Gastric Juice; Gastric Mucosa; Gastritis; Histamine; Humans; Intrinsic Factor; Iron; Ischemia; Male; Middle Aged; Peptic Ulcer; Polycythemia Vera; Stomach Ulcer; Vitamin B 12

Topics: Angiography; Arteriosclerosis Obliterans; Atherosclerosis; Barbiturates; Diagnosis, Differential; Drug Therapy; Humans; Ischemia; Leg; Salicylates; Thiamine; Thrombophlebitis; Vascular Diseases; Vascular Surgical Procedures; Vasodilator Agents; Vitamin B 12; Vitamin B Complex

Topics: Corrinoids; Disease; Hematinics; Humans; Ischemia; Leg; Lidocaine; Vitamin B 12