vitamin-b-12 and Arterial-Occlusive-Diseases

Reduction of circulating homocysteine levels by folic acid suggests an additional approach to the prophylaxis of certain forms of vascular disease related to atherogenic amino acids.

Topics: Arterial Occlusive Diseases; Arteriosclerosis; Folic Acid; Folic Acid Deficiency; Homocysteine; Humans; Metabolism, Inborn Errors; Vascular Diseases; Vitamin B 12; Vitamin B 12 Deficiency

Hyperhomocyst(e)inemia is a risk factor for atherosclerotic vascular disease, and it is associated with endothelial dysfunction. Mechanisms responsible for endothelial dysfunction in hyperhomocyst(e)inemia may involve impaired bioavailability of NO, possibly secondary to accumulation of the endogenous NO synthase inhibitor asymmetric dimethylarginine (ADMA) and increased oxidative stress. We investigated whether oral treatment with B vitamins or L-arginine normalizes endothelium-dependent, flow-dependent vasodilation (FDD) in patients with peripheral arterial occlusive disease (PAOD) and hyperhomocyst(e)inemia.. 27 patients with PAOD and hyperhomocyst(e)inemia were assigned to oral treatment with combined B vitamins (folate, 10 mg; vitamin B-12, 200 microg; vitamin B-6, 20 mg/day), L-arginine (24 g/day) or placebo, for 8 weeks in a double-blind fashion. FDD was determined by high-resolution ultrasound in the radial artery.. Vitamin B supplementation significantly lowered plasma homocyst(e)ine concentration from 15.8+/-1.8 to 8.7+/-1.1 micromol/l (P<0.01). However, B vitamins had no significant effect on FDD (baseline, 7.8+/-0.7%, B vitamins, 8.3+/-0.9%, placebo 8.9+/-0.7%; P=n.s.). In contrast, L-arginine treatment did not affect homocyst(e)ine levels, but significantly improved FDD (10.2+/-0.2%), probably by antagonizing the impact of elevated ADMA concentration (3.8+/-0.3 micromol/l) and reducing the oxidative stress by lowering urinary 8-iso-prostaglandin F(2alpha) (baseline, 76.3+/-7.1 vs. 62.7+/-8.3 pmol/mmol creatinine after 8 weeks).. Oral supplementation with combined B vitamins during 8 weeks does not improve endothelium-dependent vasodilation in PAOD patients with hyperhomocyst(e)inemia, whereas L-arginine significantly improved endothelial function in these patients. Thus, accumulation of ADMA and increased oxidative stress may underlie endothelial dysfunction under hyperhomocyst(e)inemic conditions. These findings may have importance for evaluation of homocyst(e)ine-lowering therapy.

Topics: Aged; Analysis of Variance; Arginine; Arterial Occlusive Diseases; Double-Blind Method; Female; Folic Acid; Humans; Hyperhomocysteinemia; Male; Middle Aged; Nitric Oxide Synthase; Oxidative Stress; Peripheral Vascular Diseases; Vitamin B 12; Vitamin B 6; Vitamins

Injection of hyaluronic acid (HA) filler is a common aesthetic procedure. Impairment of vision, although rare, is a devastating complication of this procedure, which may not be reversible. We report on a patient who experienced visual acuity impairment and ischemic oculomotor nerve palsy after injection of HA into the nasal dorsum. In this case, clinical signs improved within 14 days of treatment. We also provide a review of the mechanism, clinical features, risk factors, and prevention and treatment strategies relating to embolization of ocular circulation after injection of HA. Vision loss is a rare but devastating complication of injection of hyaluronic acid (HA) in the face. Visual acuity seldom recovers completely. We report on a 22-year-old Asian woman who experienced obstruction of a branch of the retinal artery after injection of HA to augment her nose. The patient's visual acuity declined shortly after the procedure, and ophthalmoplegia occurred. Combination treatment was administered to restore the perfusion and oxygen supply to the retina and optic nerve. Within 14 days of rigorous treatment, the patient experienced improvement in visual acuity, extraocular movement, and visual field defects. LEVEL OF EVIDENCE 5: Risk.

Topics: Adult; Alprostadil; Arterial Occlusive Diseases; Cosmetic Techniques; Dexamethasone; Dextrans; Female; Humans; Hyaluronic Acid; Methacrylates; Nasal Cavity; Ophthalmoplegia; Oxygen; Retinal Artery; Solanaceous Alkaloids; Timolol; Tobramycin; Vision Disorders; Vitamin B 12; Young Adult

Some recent studies indicated that administration of antiepileptic drugs (AEDs) is associated with occlusive vascular diseases. Asymmetric dimethylarginine (ADMA) is an endogenous nitric oxide (NO) synthase inhibitor and increased plasma ADMA levels are associated with cardiovascular morbidity. We hypothesized that elevated plasma ADMA concentrations exist in patients receiving AEDs and administration of AEDs may result in an increased risk of occlusive vascular disease. Thirty five newly diagnosed epilepsy patients participated, patients were classified into two groups according to their antiepileptic drug regimen. In the first group patients were treated with valproic acid (VPA, n=17) (500-1500 mg/day), and in the second group with carbamazepine (CBZ, n=18) (400-1200 mg/day). ADMA levels significantly increased after treatment in both VPA (p=0.002) and CBZ (p=0.024) groups. Homocysteine levels increased in both groups, but the difference was significant only in VPA group (p=0.005). Serum folate levels did not differ in VPA group, but significantly decreased in CBZ group (p=0.006). Vitamin B(12) levels significantly increased in VPA group (p=0.001) but did not differ in CBZ group. Correlation analysis showed that the increases in ADMA and homocysteine levels in the VPA group were higher however the differences between the groups were insignificant. The correlations of the changes between ADMA and other parameters were all insignificant in both VPA and CBZ groups. In conclusion our data suggest that elevated ADMA levels may be responsible for the increased cardiovascular risk in patients with epilepsy under AED therapy.

Topics: Adult; Anticonvulsants; Arginine; Arterial Occlusive Diseases; Carbamazepine; Drug Monitoring; Epilepsy; Female; Folic Acid; Homocysteine; Humans; Male; Statistics, Nonparametric; Valproic Acid; Vitamin B 12

Hyperhomocysteinemia (HHCA) is defined as an independent risk factor for atherothrombotic vascular disease; therefore, screening for HHCA is recommended. However, the incidence and characteristics of HHCA in patients with vascular disease remain unclear. We conducted this study in an attempt to resolve these issues.. This nonrandomized prospective study included 56 patients who were admitted with occlusive arterial disease (group I), and 39 control patients without occlusive arterial disease (group II). We recorded all the demographic data of both groups and collected blood samples for fasting homocysteine, vitamin B(12), and folic acid. All of the patients were followed up and the results were compared.. The mean concentration of homocysteine was 12.69 +/- 3.82 micromol/l in group I and 10.46 +/- 5.08 micromol/l in group II (P = 0.00048). In group I, the mean homocysteine levels for patients aged > or =70 years and those aged <70 years were 13.74 +/- 3.02 and 11.55 +/- 4.15 micromol/l, respectively (P = 0.021). There was no significant difference in mortality between the patients with HHCA and those with normal homocysteine levels during follow-up.. The incidence of hyperhomocysteinemia was higher in the patients with occlusive vascular disease than in the control patients. More evidence of the association with vitamins B(12) and folate and the benefits of homocysteine-lowering therapy is needed since we found no relationship between these vitamins and homocysteine in this study.

Topics: Aged; Aged, 80 and over; Arterial Occlusive Diseases; Case-Control Studies; Female; Folic Acid; Homocysteine; Humans; Hyperhomocysteinemia; Male; Middle Aged; Prospective Studies; Risk Assessment; Risk Factors; Vitamin B 12

It has been suggested that hyperhomocysteinemia (HHcy) is an independent risk factor for peripheral arterial occlusive disease (PAOD). However, the relationship between dietary folate and vitamin B6, cofactors in the metabolism of homocysteine (Hcy), and PAOD is unclear.. To study the relationship between dietary folate and B6 and PAOD.. Case-control population based study of 392 men older than 50 years living in Huntingdon, United Kingdom. PAOD, defined as an ankle-brachial pressure index (ABPI) < 0.9, was present in 86 (22%) of subjects. Folate, vitamin B6, and vitamin B12 intakes were calculated by means of the EPIC (European Prospective Investigation into Cancer) food frequency questionnaire.. Daily folate intake was significantly lower in case subjects (mean, 288; 95% confidence interval [CI], 266-309 microg) than in control subjects (324; 95% CI, 313-335 microg). Daily vitamin B6 intake was also lower in case subjects (2.05; 95% CI, 1.92-2.19 mg versus 2.26; 95% CI, 2.19-2.33 mg). Daily folate and vitamin B6 intakes were independent predictors of PAOD after adjusting for age, blood pressure, cholesterol levels, diabetes, and smoking status in a logistic regression model. This model suggests that increasing daily folate intake by 1 standard deviation decreased the risk of PAOD by 46%. A similar increase in daily vitamin B6 intake decreased the risk of PAOD by 29%.. In men older than 50 years, dietary folate and B6 intakes are independent predictors of PAOD. Longitudinal studies are required to determine whether dietary modification can reduce the incidence of PAOD in the population.

Topics: Aged; Aged, 80 and over; Arterial Occlusive Diseases; Cohort Studies; Diet; Diet Surveys; Folic Acid; Humans; Male; Middle Aged; Peripheral Vascular Diseases; Risk Factors; United Kingdom; Vitamin B 12; Vitamin B 6

Hyperhomocysteinemia is known to be associated with arterial occlusive vascular disease and venous thrombosis. Here, we report a young ethnic Omani patient with recurrent venous thrombosis who was found to be heterozygous for 677C-T mutation in the methyltetrahydrofolate reductase (MTHFR) enzyme. Moderate hyperhomocystenemia was also observed, in the presence of normal red cell folate and serum B12 levels. No other documented marker of hereditary thrombophilia could be demonstrated in this patient, in spite of extensive investigation on multiple occasions.

Topics: Adult; Arterial Occlusive Diseases; Erythrocytes; Folic Acid; Heterozygote; Humans; Hyperhomocysteinemia; Iliac Vein; Male; Methylenetetrahydrofolate Reductase (NADPH2); Mutation; Popliteal Vein; Vena Cava, Inferior; Venous Thrombosis; Vitamin B 12

Thioretinamide was conjugated to coenzyme B12 to produce thioretinaco. Thioretinamide, thioretinaco, and coenzyme B12 were injected weekly into Rattus rattus that were also given atherogenic doses of homocysteine thiolactone. The presence or absence of lesions in aorta-intercostal artery junctions was examined. Control rats injected with homocysteine thiolactone (CON-Hcy) had 56.6 +/- 5.8% lesions when compared to 34.8 +/- 3.4% in control rats injected with saline (CON-Sal). Rats that received homocysteine thiolactone injection with thioretinamide (NHTR-Hcy), thioretinaco ((NHTR)2B12-Hcy), and coenzyme B12 (B12-Hcy) had 30.1 +/- 4.2%, 27.5 +/- 3.5%, and 22.8 +/- 3.0% lesions, respectively. These lesion rates were not different from those of rats receiving thioretinamide (NHTR-Sal), thioretinaco ((NHTR)2B12-Sal), and coenzyme B12 (B12-Sal) which were 31.3 +/- 1.8%, 29.8 +/- 3.9%, and 32.0 +/- 4.6%, respectively. In this study the percentage of intercostal artery lesions in rats receiving thioretinamide and homocysteine (NHTR-Hcy), coenzyme B12 and homocysteine (B12-Hcy), and thioretinaco and homocysteine ((NHTR)2/B12-Hcy) were significantly lower, 53.2%, 48.6%, and 40.3% respectively, compared to than that of the control group receiving homocysteine (CON-Hcy). Thioretinaco, thioretinamide, and coenzyme B12 provided protective effects against the atherogen homocysteine thiolactone. A new method for the synthesis of the N-substituted derivative of homocysteine thiolactone, thioretinamide, was also reported.

Topics: Animals; Aorta, Thoracic; Arterial Occlusive Diseases; Arteries; Arteriosclerosis; Cobamides; Female; Food; Homocysteine; Magnetic Resonance Spectroscopy; Mass Spectrometry; Propylene Glycol; Rats; Tissue Fixation; Tretinoin; Vitamin B 12; Weight Gain

A case-control study was undertaken involving 51 consecutive patients with peripheral artery obstructive disease (PAOD) scheduled for angioplasty. Blood samples of these patients were analysed for plasma homocysteine (tHcy) and levels of vitamin B12 and folate, and the MTHFR gene was assessed for mutation. Patients were compared with age- and sex-matched controls who did not present with cardiovascular risk factors. Mean tHcy did not differ between cases and controls (13.3 +/- 5.7 and 12.6 +/- 4.9 micromol/l, P = 0.49). More patients were above the 95th percentile as determined from the data in the control group with an odds ratio (OR) that almost reached statistical significance [OR, 2.8; 95% confidence interval (CI), 0.9-8.7], but on separate analyses only female patients showed higher tHcy than female controls (15.6 versus 12.0 micromol/l, P = 0.05), with an odds ratio for tHcy above the 95th percentile of 10.5 (95% CI, 1.1-96.6). The TT genotype of the MTHFR gene was found in 24% of the patients and in 12% of the controls (OR, 2.3; 95% CI, 0.8-6.7). Our findings point to a modest association between tHcy and PAOD, with a difference between cases and controls restricted to the highest percentile in female patients. A weak but not significant association was also found for the TT genotype of the MTHFR gene.

Topics: Adult; Aged; Arterial Occlusive Diseases; Case-Control Studies; Female; Folic Acid; Genotype; Homocysteine; Humans; Male; Methylenetetrahydrofolate Reductase (NADPH2); Middle Aged; Mutation; Oxidoreductases Acting on CH-NH Group Donors; Peripheral Vascular Diseases; Vitamin B 12

Elevated serum total homocysteine, an established risk factor for peripheral arterial disease, is influenced by the vitamin B12 and folate status. Since these vitamins are inversely correlated with erythrocyte mean corpuscular volume, an investigation of whether mean corpuscular volume is higher in patients with symptomatic peripheral arterial disease than in healthy subjects was performed. Furthermore, a determination of predictors of increased mean corpuscular volume levels in this population free of symptomatic coronary artery disease, cerebrovascular disease, and diabetes mellitus was carried out. From 469 consecutive patients with symptomatic peripheral arterial disease, 100 fulfilled study inclusion criteria. Peripheral arterial disease was confirmed by angiography. One hundred age-matched subjects without peripheral arterial disease as verified by ankle-brachial index measurements >0.9 served as control subjects. Patients with PAD displayed a significantly higher mean corpuscular volume level (94.5 fl) than control subjects (90.9 fl, p<0.001). Logistic regression analysis showed that current smoking status (p<0.001) and mean corpuscular volume (p=0.009), but not total homocysteine or lipid parameters discriminated case control status. In addition, logistic regression analysis revealed a relationship of mean corpuscular volume with smoking (p=0.001), gamma-glutamyltransferase (p<0.001), and total homocysteine (p=0.012). This model predicted mean corpuscular volume values with an accuracy of 83%. Elevated mean corpuscular volume is a predictor of symptomatic peripheral arterial disease in the sample studied. A deficiency of folate and/or vitamin B12 may be responsible for this observation, as indicated by the correlation of mean corpuscular volume with total homocysteine. Due to the additional association of mean corpuscular volume with smoking and gamma-glutamyltransferase, an unhealthy lifestyle with low vitamin intake may cause elevated mean corpuscular volume values in patients with PAD.

Topics: Adult; Aged; Aged, 80 and over; Arterial Occlusive Diseases; Erythrocyte Indices; gamma-Glutamyltransferase; Homocysteine; Humans; Male; Middle Aged; Regression Analysis; Smoking; Vitamin B 12