Preferential response of glutathione-related enzymes to folate-dependent changes in the redox state of rat liver

BACKGROUND

Oxidative stress likely constitutes an important contributing factor in the onset of degenerative diseases associated with folate deficiency. Direct, as well as homocysteine-linked, antioxidant properties of folate could explain its preventive effect on these pathologies.

AIM OF THE STUDY

Our study aimed at determining the changes in the redox status of adult rats as a function of folate intake.

METHODS

Adult male rats were pair-fed for 4 weeks with a semi-synthetic diet containing 0, 0.5, 1.5, 8 or 20 mg of folic acid/kg. Folate and homocysteine concentrations, redox status markers and antioxidant enzyme activities were measured in the plasma and/or liver of the rats. A principal component analysis of the overall data was performed to draw a general scheme of the changes observed between the conditions.

RESULTS

Folate deficiency caused increased homocysteinemia and features of oxidative stress including reduced plasma antioxidant capacity together with increased lipid peroxidation in liver and heart. This was associated with an increase in the specific activity of several enzymes involved in liver glutathione metabolism (glutathione peroxidase, glutathione reductase and glutathione S-transferase), suggesting an adaptive tissue response to the oxidative stress induced by folate deficiency. In contrast, no such variation was observed for hepatic superoxide dismutase and catalase.

CONCLUSION

Despite no changes in hepatic levels of total glutathione, our findings indicate that glutathione-dependent antioxidant pathways could be particularly involved in the compensatory mechanism committed by liver to counteract the oxidative stress induced by folate deficiency. They also suggest that folate supplementation may not be associated with a better antioxidant protection of rats.

Cough mixture abuse as a novel cause of folate deficiency: a prospective, community-based, controlled study

Cough mixture abuse has been reported to cause severe folate deficiency and neurological defects. We carried out a prospective case-controlled survey to confirm this association and define the incidence and severity of the problem. A total of 57 cough mixture abusers and 47 other substance abusers (controls) were studied. When compared with controls, cough mixture abusers had a high incidence of low folate levels that could only be detected by screening.

Epidemiological survey of vitamin deficiencies in older Thai adults: implications for national policy planning

OBJECTIVE

To examine the prevalence and risk factors of vitamin deficiencies among older Thai adults.

METHODS

The cross-sectional study was conducted in four rural communities, one from each of the four main regions of Thailand. In total, 2336 subjects aged 60 years and over were recruited. Anthropometric variables, demographic data, blood glucose and lipid profile, albumin, globulin and blood levels of vitamin A, beta-carotene, folic acid, vitamin B12, vitamin C, vitamin E and vitamin B1 were all measured.

RESULTS

The prevalence of vitamin deficiencies was 0.6% for vitamin B12, 6.1% for vitamin A, 9.9% for vitamin C, 30.1% for vitamin B1, 38.8% for erythrocyte folate, 55.5% for vitamin E and 83.0% for beta-carotene. Male gender was a common risk factor for at least three vitamin deficiencies, i.e. beta-carotene, folate and vitamin E. Being a manual worker was a common risk factor of beta-carotene and vitamin B1 deficiency. Poor income was found as a risk factor only in erythrocyte folate deficiency while increasing age was a significant factor only in vitamin C deficiency.

CONCLUSION

The prevalence of vitamin deficiencies among older Thai people was quite different from that found in Western countries, reflecting different socio-economic backgrounds. Vitamin deficiency was not only from poor food intake but also from the dietary habit of monotonous food consumption in older people. Some common associated factors of atherosclerosis were also significantly related to folate and vitamin E deficiencies.

Influence of folic acid-fortified foods on folate status in a folate depletion–repletion rat model

An increasing number of foods fortified with varying levels of folic acid are appearing in the market place, targeted either at the general population or at specific consumer groups. Although it is assumed that the folate in these products should be highly bioavailable, there is a need to carry out studies to ascertain that this is, in fact, the case. The present study investigated the ability of selected folic acid-fortified foods (targeted at different types of consumer) to increase the folate status of folate-deficient rats. Forty-two weanling male rats (Wistar strain) were fed a folate-deficient diet containing 1 % succinyl sulfathiazole (w/w) for 28 d. Following depletion, seven rats were randomly assigned to each of five repletion diets containing folic acid, Complan®, Slim Fast®, Opti-Fuel2®or Cola Coa®calculated to provide 200 μg folate/kg of each diet. Calculations were based on folate information from the product labels. After a further 28 d, plasma, liver and kidney folate concentrations were determined by microbiological assay. Plasma homocysteine was measured by HPLC as a functional indicator of folate status. The folate content of the foods was measured by tri-enzyme extraction followed by microbiological assay. Our analyses suggest that there may be considerable inaccuracies on the part of the manufacturers in relation to the folate declarations on the product labels. Despite this, the four foods evaluated were highly effective in elevating plasma, liver and kidney folate and lowering plasma homocysteine concentrations in rats. These results lend support to the policy of food fortification with folic acid as a means of raising the folate status of the population, and in particular to the fortification of specific foods which may target areas of the population where increased folate status is most needed.

The coexistence of other micronutrient deficiencies in anaemic adolescent schoolgirls in rural Bangladesh

OBJECTIVE

To investigate the prevalence of selected micronutrient deficiencies amongst anaemic adolescent schoolgirls in rural Bangladesh and to examine their relationship with haemoglobin (Hb) levels.

DESIGN

A cross-sectional study.

SETTING

Girls' high schools in rural areas of Dhaka District in Bangladesh.

SUBJECTS AND METHODS

Three hundred and ten anaemic adolescent girls aged 14-18 years from eight schools participated in the study. Information on personal characteristics and food habits were collected by interview. Parents were asked about their socio-economic conditions. Anthropometric data and blood samples were collected following the interview.

RESULTS

Twenty-eight per cent of the girls had depleted iron stores (serum ferritin <12.0 microg/l), 25% had folic acid deficiency (red blood cell folic acid <317 nmol/l), 89% had vitamin B(2) (erythrocyte glutathione reductase activity coefficient > or =1.4) and 7% had vitamin B(12) deficiencies (serum vitamin B(12) <150 pmol/l). Although the prevalence of vitamins A and C deficiency was very low, a significant proportion had low vitamin A (serum retinol between 0.70 and <1.05 micromol/l) and vitamin C status (plasma ascorbic acid between 11.4-23.0 micromol/l). Frequency of consumption of meat, serum ferritin and vitamin B(2) status were found to be strongly related to Hb by multiple regression analysis. For 1 microg/l change in serum ferritin, there was a 0.13 g/l change in Hb when adjusted for other factors.

CONCLUSIONS

There is coexistence of micronutrient deficiencies among anaemic adolescent girls in rural Bangladesh, although they do not suffer from energy deficiency. Of all micronutrients, only iron and vitamin B(2) concentrations were found to be related to the Hb concentration.

Distribution of Anemia Associated with Micronutrient Deficiencies Other than Iron in a Probabilistic Sample of Mexican Children

BACKGROUND

This investigation aims to explore the association among anemia and vitamins A, C, and folate deficiencies in a probabilistic sample of Mexican children.

METHODS

Data on hemoglobin, serum vitamins A and C and folate concentrations and percent transferrin saturation (PTS) in children 0.5-11 years (n = 1,770) were extracted from the database of the probabilistic Mexican National Nutrition Survey 1999 (NNS-99).

RESULTS

Overall, 16.6% of children were anemic. Iron deficiency children with or without anemia had more frequent low serum retinol (40.6 vs. 16% and 27.7 vs. 11.9%, p < 0.05, respectively) and lower hemoglobin folate (11.5 vs. 22%, p < 0.05) than their non-iron deficiency counterparts. Mean concentrations of serum iron (p < 0.01), folate (p < 0.001) and retinol (p < 0.0001), but not ascorbic acid (p < 0.6), were significantly lower in anemic than in nonanemic children. In a linear regression model, 15% of hemoglobin variation in children was explained by retinol, folate and PTS, but not vitamin C (p <0.0001).

CONCLUSION

Anemia was mostly associated with iron deficiency and with a lesser proportion of folate and vitamin A deficiencies. Vitamin A deficiency might be overestimated since iron deficiency may lower serum retinol concentrations. Interventions aimed to reduce anemia in this population must consider interactions between those micronutrients in designing strategies.

Folate deficiency is associated with nutritional anaemia in Lebanese women of childbearing age

OBJECTIVE

The objective of this study was to identify the determinants of anaemia in Lebanese women of childbearing age attending health centres in Lebanon.

DESIGN

Cross-sectional study carried out between May and December 2003. Anthropometric measurements as well as sociodemographic, health and dietary intake data were collected using a questionnaire. Haemoglobin (Hb), plasma ferritin, plasma folate and vitamin B12 were assessed using standard laboratory methods.

SETTING

Governmental health centres in Lebanon.

SUBJECTS

Four hundred and seventy non-pregnant Lebanese women aged 15-45 years.

RESULTS

Anaemia (Hb <12 g dl(-1)) and iron deficiency (ferritin <15 microg l(-1)) were prevalent in 16.0 and 27.2% of the study sample, respectively. Of the total sample, 7.7% had iron-deficiency anaemia. The percentage of women with either Hb or ferritin deficiency or both was 35.6%. Plasma folate and vitamin B12 deficiency was reported in 25.1 and 39.4%, respectively, and 12.6% of the women had both folate and vitamin B12 deficiencies. Of the anaemic group, 48.0% of the women had iron deficiency. The intake of iron was lower in iron-deficient than in non-deficient women and a positive relationship was shown between folate intake and its corresponding serum levels. Regression analysis showed that ferritin, plasma folate and family history of anaemia were significant determinants of the anaemia in the sample of women.

CONCLUSIONS

Anaemia not related to iron deficiency was partly explained by plasma folate deficiency. Measures to control folate and iron deficiency should be considered.

Vitamin deficiency and hyperhomocysteinemia in pseudoexfoliation glaucoma

Pseudoexfoliation syndrome (PEX) is a systemic disorder characterized by the deposition of an abnormal fibrillar material in ocular and various extraocular tissues. It represents the most common identifiable cause of glaucoma (PEX glaucoma = PEXG). Due to similar pathogenetic mechanisms, glaucoma has been called "ocular Alzheimer's disease". PEXG and Alzheimer's disease share common associations such as the higher prevalence of hyperhomocysteinemia in both disorders. In order to investigate the cause of hyperhomocysteinemia in PEXG, we evaluated B-vitamin levels (folate, B12, B6) and their associations with homocysteine (Hcy) in plasma of 70 PEXG patients and 70 control subjects. Folate, vitamin B12 and B6 levels were significantly decreased and associated with elevated Hcy levels in PEXG. Low B-vitamin levels in PEX might also help explain, at least in part, the higher prevalence of B-vitamin deficiency in disorders associated with PEX such as Alzhemier's disease.

Evaluation of folate status by serum and erythrocyte folate levels and dietary folate intake in Taiwanese schoolchildren

The folate status and dietary folate intake of Taiwanese schoolchildren was investigated by analysis of both serum and red blood cell (RBC) folate levels and dietary folate intake in 1105 boys and 958 girls aged 6-13 years sampled from the Nutrition and Health Survey in Taiwan Elementary School Children 2001-2002 (NAHSIT Children 2001-2002). Mean serum folate levels were 18.3+/-8.8 nmol/L (8.1+/-3.9 ng/mL) in boys and 20.3+/-9.7 nmol/L (9.0+/-4.3 ng/mL) in girls. Mean RBC folate levels were 700+/-320 nmol/L (308+/-141 ng/mL) in boys and 751+/-347 nmol/L (331+/-153 ng/mL) in girls. The prevalence of serum folate deficiency was 1.4% in boys and girls, and the prevalence of marginal serum folate deficiency (7-14 nmol/L) was 31.1% in boys and 25.8% in girls. In addition, 8.5% of boys and 7.4% girls had RBC folate deficiency (RBC folate < 318 nmol/L), and 17% of children had marginal RBC folate deficiency (RBC folate of 318-454 nmol/L). Our results suggesting that Taiwanese schoolchildren have poor folate status especially during periods of rapid growth and development such as the transition from childhood to early adolescence (boys at age 12-12.9, girls at age 11-12.9). The average estimated folate intakes were 269+/-9 microg/d in boys and 259+/-9 microg/d in girls, and 42% of Taiwanese schoolchildren had a dietary folate intake below 2/3 of the RDA, indicating a poor dietary folate intake in this population. This study shows that the folate status of Taiwanese schoolchildren is currently inadequate and strategies are needed for improvement.

Plasma B vitamins and their relation to the severity of chronic heart failure

BACKGROUND

Total homocysteine (tHcy) has been linked to the severity of chronic heart failure (CHF). Elevated tHcy concentrations are mainly caused by folate and vitamin B-12 deficiencies.

OBJECTIVE

We hypothesized that folate and vitamin B-12 deficiencies can explain the relation between tHcy and the severity of CHF.

DESIGN

We investigated 987 CHF patients. All subjects underwent a physical examination and blood sampling. Cardiac catheterization was performed in 929 patients and echocardiography in 460 patients. Serum tHcy, folate, vitamin B-12, and N-terminal pro-B-type natriuretic-peptide (NT-proBNP) were measured and renal and hepatic function were studied.

RESULTS

tHcy increased with increasing New York Heart Association (NYHA) classes of heart failure (P < 0.001) and correlated with the left ventricular ejection fraction (EF; r = -0.150, P < 0.001). Contrary to the hypothesis, vitamin B-12 (P < 0.001) increased with NYHA class (P < 0.001) and was negatively correlated with EF (r = -0.080, P = 0.015). Folate showed no relation with NYHA class or EF. Comparable results were obtained for NT-proBNP (tHcy: r = 0.27, P < 0.001; vitamin B-12: r = 0.091, P = 0.004; folate: r = -0.045, P = 0.169). The correlations between tHcy, EF, and NT-proBNP were significantly stronger in patients without coronary artery disease (CAD) than in those with CAD. Regression analysis showed that tHcy, but not B vitamins, is a strong predictor of EF and NT-proBNP.

CONCLUSIONS

This study showed that tHcy, but not folate and vitamin B-12, is related to clinical, echocardiographic, and laboratory variables of CHF, which indicates a relation between tHcy and the severity of CHF. This relation is stronger in patients without CAD. The lack of association of folate and the paradoxical relation of vitamin B-12 with CHF can possibly be explained by a disturbance in hepatic homeostasis.

MicroRNA responses to cellular stress

Recent work has begun to explore the instrumental role that small noncoding RNA species, particularly microRNAs (miRNA), have both in classifying human tumors and in directing embryonic development. These studies suggest that developmental programs in essentially all organisms studied are set, in part, by varied expressions of miRNAs and that neoplasia is characterized by altered expression of miRNAs. Reasoning that these observations are linked, we examined whether cellular exposures that induce both developmental anomalies and cancer alter miRNAs. Using microarrays of 385 known human miRNAs, we studied human lymphoblastoid cells grown under various conditions or treatments. Folate deficiency induced a pronounced global increase in miRNA expression. We observed no significant alteration in miRNA expression in cells treated with gamma-irradiation, whereas exposure to sodium arsenite led to global increases in miRNA expression. The miRNA hsa-miR-222 was identified from these arrays as significantly overexpressed under folate-deficient conditions, and this finding was confirmed in vivo in human peripheral blood from individuals with low folate intake. Alterations to cellular miRNA expression profiles represent a novel mode of action of folate deprivation and arsenic exposure, and specific alterations in miRNA expression may be a powerful biomarker for these and other toxins with serious effects on human health.

Low Folate and the Risk of Cognitive and Functional Deficits in the Very Old: The Monzino 80-plus Study

OBJECTIVE

To cross sectionally investigate the association of serum vitamin B(12) and folate concentrations with cognitive and functional ability in the very old in the general population.

METHODS

Serum vitamin B(12) and folate concentrations were assessed in 471 consenting subjects participating in the Monzino 80-plus study (mean age: 87.4 years), a door-to-door population-based survey among very old subjects living in Northern Italy. Cognitive and functional evaluations included Mini-Mental State Examination (MMSE), Instrumental Activities of Daily Living (IADL) and Spontaneous Behavior Interview-basic Activities of Daily Living (SBI-bADL).

RESULTS

MMSE, IADL and SBI-bADL scores were all significantly correlated with folate concentrations (respectively: r = 0.36, r = -0.39, r = -0.35; p < 0.0001), while no significant associations were found with vitamin B(12) concentrations. When entered into multiple linear regression analyses with several covariates, folate showed a highly significant, curvilinear association with both cognitive and functional scores (p < 0.0001). Subjects in low and middle folate tertiles had significantly higher odds ratios for dementia (p < 0.0001; adjusted ORs = 5.40 and 6.56, lower 95% CIs 2.53 and 3.11, higher 95% CIs 12.73 and 15.29).

CONCLUSIONS

Findings of this population-based study suggest that subclinical folate deficiency may represent a risk factor for the cognitive decline associated with aging that could contribute to AD as well as other dementia development.

Folate depletion in human lymphocytes up-regulates p53 expression despite marked induction of strand breaks in exons 5-8 of the gene

Low dietary folate intake is associated with an elevated risk for carcinogenesis. One putative mechanism by which folate depletion promotes carcinogenesis is by inducing gene-specific strand breakage and impaired expression of affected genes. Primary human lymphocytes were cultured in media containing 15, 30 or 120 nM folic acid. p53 strand breaks, gene and protein expression, and p21 transcript were determined. Cells grown in 15 nM folate developed significant levels of p53 strand breaks, reflected by reductions in amplifiable DNA from p53 exons 5-8 (approximately 40% loss, P<0.0001) and exons 7-8 (approximately 26% loss, P<0.0001) compared to 30 and 120 nM. Nevertheless, steady-state p53 transcript was elevated two-fold in 15 and 30 compared to 120 nM (P<0.001). p53 protein abundance increased with decreasing media folate, as did p21 transcript. The cytokinesis-block micronucleus assay demonstrated a three-fold increase in chromosomal damage at the two lower folate concentrations (P<0.01). In primary human lymphocytes, folate depletion induces a marked increase in p53 exons 5-8 breaks, but does not reduce steady-state levels of p53 mRNA, protein, or impair downstream signaling. The induction of p53 strand breaks by folate depletion does not impair p53 expression or action within all human cell lines.

Predicting iron and folate deficiency anaemias from standard blood testing: the mechanism and implications for clinical medicine and public health in developing countries

Background

Developing countries have high prevalence of diseases, but facilities to diagnose and treat them are limited. We must use available resources in ways not needed where there are sophisticated equipment and trained staff. Anaemia is common; iron deficiency affects health and productivity; folate deficiency in pregnant women causes foetal abnormalities. Few developing countries can measure serum folate or ferritin, but standard automated blood analyses are widely available and can help predict folate and iron deficiency. The RDW-CV% (coefficient of variation of the red cell width) measures the variability in the size of red blood cells (RBC) in routine automated analysis of blood cells, but is seldom reported. Levels of RDW-CV% and haemoglobin (Hb) can predict iron deficiency anaemia.

Method and results

I have written a computer model based on the standard mechanism for blood formation and destruction. This shows that before anaemia develops and during recovery, there are both normal and abnormal RBC (small in iron deficiency and large in folate deficiency) in the circulation. The model calculates the abnormality in the RDW-CV% in standard automated blood analyses. In early iron deficiency and during recovery the full blood count shows the Hb near the lower limit of normal, a low MCV and a high RDW-CV%. A similar pattern, but with a higher MCV, develops in folate deficiency. Folate deficiency is often brief and may not cause anaemia. The high RDW-CV% may persist for three months.

Conclusion

This long footprint could be medically useful for detecting folate deficiency and so limiting foetal damage in individuals and communities. Few clinicians or public health workers know about RDW-CV%. Standard blood reports for clinical use should include the RDW-CV% and note the possible significance of abnormal values.

Low folate levels may protect against colorectal cancer

BACKGROUND AND AIMS

Dietary folate is believed to protect against colorectal cancer (CRC). However, few studies have addressed the role of circulating levels of folate. The aim of this study was to relate prediagnostic plasma folate and homocysteine concentrations and the methylenetetrahydrofolate reductase (MTHFR) 677C>T and 1298A>C polymorphisms to the risk of developing CRC.

SUBJECTS

Subjects were 226 cases and 437 matched referents from the population based Northern Sweden Health and Disease Cohort.

RESULTS

We observed a bell-shaped association between plasma folate concentrations and CRC risk; multivariate odds ratio for middle versus lowest quintile 2.00 (95% confidence interval (CI) 1.13-3.56). In subjects with follow up times greater than the median of 4.2 years however, plasma folate concentrations were strongly positively related to CRC risk; multivariate odds ratio for highest versus lowest quintile 3.87 (95% CI 1.52-9.87; p trend = 0.007). Homocysteine was not associated with CRC risk. Multivariate odds ratios for the MTHFR polymorphisms were, for 677 TT versus CC, 0.41 (95% CI 0.19-0.85; p trend = 0.062), and for 1298 CC versus AA, 1.62 (95% CI 0.94-2.81; p trend = 0.028). Interaction analysis suggested that the result for 1298A>C may have been largely due to linkage disequilibrium with 677C>T. The reduced CRC risk in 677 TT homozygotes was independent of plasma folate status.

CONCLUSIONS

Our findings suggest a decreased CRC risk in subjects with low folate status. This possibility of a detrimental component to the role of folate in carcinogenesis could have implications in the ongoing debate in Europe concerning mandatory folate fortification of foods.

Folic acid and the treatment of depression

Reduced plasma, serum, or red blood cell folate is commonly found in major depressive illnesses. Supplementing antidepressant medication with folic acid enhances the therapeutic effect. Although more work is required to confirm these beneficial results, it is suggested that, meanwhile, 2 mg of folic acid should be given during the acute, continuation, and maintenance treatment of depression.

Distinct effects of folate and choline deficiency on plasma kinetics of methionine and homocysteine in rats

Both folate and betaine, a choline metabolite, play essential roles in the remethylation of homocysteine to methionine. We have studied the effects of folate and choline deficiency on the plasma kinetics of methionine, especially remethylation of homocysteine to methionine, by means of stable isotope methodology. After a bolus intravenous administration of [(2)H(7)]methionine (5 mg/kg body weight) into the rats fed with folate-, choline-, folate + choline-deficient or control diets, the plasma concentrations of [(2)H(7)]methionine, demethylated [(2)H(4)]homocysteine, and remethylated [(2)H(4)]methionine were determined simultaneously with endogenous methionine and homocysteine by gas chromatography-mass spectrometry-selected ion monitoring. The total plasma clearance of [(2)H(7)]methionine was not significantly different among groups, suggesting that the formation of [(2)H(4)]homocysteine from [(2)H(7)]methionine was not influenced by deficiencies of folate and choline. The area under concentration-time curve of [(2)H(4)]homocysteine significantly increased in the folate- and folate + choline-deficient group as compared with the control, but not in the choline-deficient group. The time profile of plasma concentrations of [(2)H(4)]methionine in the folate-deficient group was the same as the control group, whereas the appearance of [(2)H(4)]methionine in plasma was delayed in the choline- and folate + choline-deficient group. These results suggested plasma levels of remethylated methionine were influenced by choline deficiency rather than folate deficiency.

[Vitamin B12 and folate in non-institutionalized urban older people]

Vitamin B12 and folate deficiencies are the main nutritional determinants of hyperhomocysteinemia, which is an independent risk factor for cardiovascular diseases. There is scarce information about nutritional status on vitamin B12 and serum levels of folate in Mexican older people. The objective was to evaluate the nutritional status of vitamin B12 and folic acid concentration in non-institutionalized, urban elderly men and women subjects. One hundred volunteers over 60 years were included in this cross-sectional study. Serum levels of vitamin B12 and folate were measured. In addition some biochemical and anthropometric indicators were also evaluated. Considering serum values of vitamin, 30% had vitamin B12 deficiency, 52% normal status and 18% with high levels. None subjects had folic acid deficiency, by the contrary, a high proportion (62%) showed elevated levels in serum. There was an effect of sex on vitamin B12 status. Elderly men showed significantly lower levels of vitamin B12, and it was according with significant higher prevalence of vitamin B12 deficiency in this group as compared with the women group. The high proportion of vitamin B12 deficiency found in this study underline a possible public health problem and guarantee further survey-studies about vitamin B12 status and to explore causes and consequences of the deficiency. Finally, due the sample size and the design of the study, the results must be seen with caution and not try to generalize.

Determinants of fasting total serum homocysteine levels in liver transplant recipients

OBJECTIVES

Homocysteine (HCY) is a sulfur-containing amino acid considered to be a marker for a relative folate deficiency. Hyperhomocysteinemia is a known risk factor for development of cardiovascular disease, vascular dementia, depression, and possibly some carcinogeneses. Liver transplant recipients have an increased risk for cardiovascular disease because of a high incidence of obesity, arterial hypertension, diabetes mellitus, and hyperlipidemia. The aim of this study is to elucidate the determinants for hyperhomocysteinemia as an additional risk factor in these patients.

MATERIALS AND METHODS

Seventy stable liver transplant recipients, 48 men (mean age, 50+/-11 years) and 22 women (mean age, 52+/-13 years) had their serum homocysteine levels tested after orthotopic liver transplantation. For mainstay immunosuppression, 53 patients were treated with tacrolimus, 10 with cyclosporine, 3 with mycophenolate mofetil, and 4 with sirolimus. Fasting blood samples were obtained and analyzed immediately (within 1 hour) for total serum homocysteine by high-performance liquid chromatography.

RESULTS

In all patients, mean homocysteine levels were 22.7+/-14 micromol/L (normal range, 9-15 micromol/L). Forty-six patients were found to have homocysteine levels>15 micromol/L, and all 70 recipients had homocysteine levels>9 micromol/mL. In our patients, increased homocysteine levels correlated well with body mass index and renal function. Homocysteine levels in patients receiving cyclosporine were higher than those in patients receiving tacrolimus (22.3+/-6 vs 17.9+/-12 micromol/L, P<.05).

CONCLUSIONS

Overall, homocysteine levels are significantly increased in liver transplant recipients. Homocysteine levels correlate well with obesity, renal function, and the particular immunosuppressant protocol. Therefore, a specific treatment for patients after liver transplantation (eg, one with folates) might reduce the risk of complications resulting from hyperhomocysteinemia.

Kazakhstan: a folate-deficient area?

OBJECTIVE

In the Republic of Kazakhstan, located in central Asia, the traditional diet consists mainly of meat, and vegetable intake tends to be deficient. This eating lifestyle may contribute to folate deficiency, which is closely linked to abnormal homocysteine (HCY) metabolism.

SUBJECTS AND METHODS

In order to evaluate current folate status in the healthy Kazakh population, we screened serum folate and plasma HCY in 50 healthy Kazakh adults aged 20-65 years (KZH) and 60 healthy Japanese control subjects aged 27-65 years (JPN).

RESULTS

Serum levels of folate were significantly lower in KZH than in JPN (3.1 vs 10.0 ng/ml, P<0.01). Fifty of 61 (82.0%) subjects in KZH but none in JPN showed low concentrations of folate (<3.6 ng/ml). Plasma levels of HCY were significantly higher in KZH than in JPN (13.2 vs 7.8 nmol/ml, P<0.01).

CONCLUSIONS

Our findings strongly suggest that owing to the insufficient intake of vegetables, folate deficiency exists in Kazakhstan. Furthermore, hyperhomocysteinemia was observed in this group, probably owing to the secondary effects of folate deficiency.

High frequency of maternal vitamin B12 deficiency as an important cause of infantile vitamin B12 deficiency in Sanliurfa province of Turkey

BACKGROUND

Vitamin B12 deficiency in infancy may cause failure to thrive, severe neurological disorders and megaloblastic pancytopenia. It is well known that infants born with deficient vitamin B12 storage have increased the risk of vitamin B12 deficiency. Vitamin B12 deficiency is more prevalent in infancy in Sanliurfa province (at the southeast region of Turkey).

AIM OF THE STUDY

The aim of this study was to determine the frequencies of vitamin B12, folic acid and iron deficiencies in pregnants and their babies at birth and to what extend the mothers' deficiency becomes effective on babies' deficiencies.

METHODS

The study groups were constituted by 180 pregnant women and their single and term babies. Venous blood samples of pregnants were obtained 1-3 h before delivery and babies' cord bloods were collected at birth. Vitamin B12 and folic acid levels were measured with electro chemiluminiscence method; serum iron and iron binding capacities were measured by colorimetric method and complete blood counts were performed by automatic blood counter.

RESULTS

Mean vitamin B12 levels in maternal and cord blood serum were 130 +/- 61.7 pg/ml and 207 +/- 141 pg/ml; mean folic acid levels were 8.91 +/- 6.46 ng/ml and 17.8 +/- 11.8 ng/ml; mean serum iron levels were 56.9 +/- 37.5 microg/dl and 147 +/- 43.2 microg/dl; and mean transferrin saturations were 11.8 +/- 8% and 65.6 +/- 24%, respectively. There were vitamin B12 deficiency (<160 pg/ml) in 72% of the mothers and 41% of the babies, and severe deficiency (<120 pg/ml) in 48% of the mothers and 23% of the babies. Folic acid deficiency was found in 12% of the mothers, but was not found in the babies. There were iron deficiency in 62% of the mothers and 1% of the babies. There were statistically significant correlation between maternal and cord blood serum vitamin B12 levels (r = 0.395, P < 0.001) and folic acid levels (r = 0.227, P = 0.017), while there were no correlation between maternal and cord blood iron levels and transferrin saturations.

CONCLUSION

The study results showed that vitamin B12 deficiency is prevalent in pregnants in this region and that 41% of infants have born with deficient vitamin B12 storages. Therefore, prophylactic use of vitamin B12 by pregnant women in Sanliurfa and other poor communities could have considerable benefits to prevent vitamin B12 deficiency and its complications in infants.