Linkages of antioxidant, micronutrient, and socioeconomic status with the degree of oxidative stress and lens opacity in indian cataract patients

OBJECTIVES: We assessed the status of micronutrients and oxidative stress in blood and lens and examined their linkages with lens degeneration in cataract patients. METHODS: For 143 cataract patients (50 to 70 y) and 100 age- and sex-matched controls of low- and high-income groups, oxidative stresses such as as thiobarbituric acid reactive substances (TBARS) and levels of Zn, Fe, Se, Mn, riboflavin, thiamine, vitamin C, vitamin A, beta-carotene, ceruloplasmin, and hemoglobin in plasma were assessed. In extracted cataractous lenses, the ratio of soluble to total proteins (S:T ratio), turbidity, TBARS, and levels of Zn, Fe, Cu, Mn, and Se, were estimated. RESULTS: Plasma TBARS were higher in cataract patients (40% to 66%) than in controls. Levels of hemoglobin and serum ceruloplasmin and plasma levels of Fe, vitamin C, vitamin A, beta-carotene, thiamine, and riboflavin were subnormal in all patients and lowest in low-income patients. Plasma TBARS were positively associated with turbidity (r = 0.30, P < 0.05) but negatively with hemoglobin and ceruloplasmin (r = -0.31 and -0.34, P < 0.05). Plasma malondialdehyde was correlated positively with plasma Se (r = 0.32, P < 0.01), whereas a negative and highly significant correlation was seen with lens Fe (r = -0.53 P < 0.001). Further, plasma TBARS, lens TBARS, and lens turbidity showed significant correlation with opacity grades obtained on a slit-lamp biomicroscope (r = 0.54, 0.37, and 0.34, P < 0.05). The highest S:T ratio was 0.68, indicating a higher threshold for cataract formation in humans. The S:T ratio was negatively associated with lens Fe (r = -0.38, P < 0.001). Turbidity was negatively correlated with Fe levels (r = -0.24, P < 0.001). CONCLUSIONS: Oxidative stress of the lens had direct influence on the solubility of lens proteins, leading to an increase in the opacity of lens. Plasma TBARS can be used as biomarkers of degeneration in the lens. Nutritional etiology of cataractogenesis may be different in the two socioeconomic classes.     

Amelioration of hyperglycaemia and its associated complications by finger millet ( Eleusine coracana L.) seed coat matter in streptozotocin-induced diabetic rats

Finger millet (Eleusine coracana) is extensively cultivated and consumed in India and Africa. The millet seed coat is a rich source of dietary fibre and phenolic compounds. The effect of feeding a diet containing 20% finger millet seed coat matter (SCM) was examined in streptozotocin-induced diabetic rats. Diabetic rats maintained on the millet SCM diet (diabetic experimental (DE) group) for 6 weeks exhibited a lesser degree of fasting hyperglycaemia and partial reversal of abnormalities in serum albumin, urea and creatinine compared with the diabetic control (DC) group. The DE group of rats excreted comparatively lesser amounts of glucose, protein, urea and creatinine and was accompanied by improved body weights compared with their corresponding controls. Hypercholesterolaemia and hypertriacylglycerolaemia associated with diabetes were also notably reversed in the DE group. Slit lamp examination of the eye lens revealed an immature subcapsular cataract with mild lenticular opacity in the DE group of rats compared to the mature cataract with significant lenticular opacity and corneal vascularisation in the DC group. Lower activity of lens aldose reductase, serum advanced glycation end products and blood glycosylated Hb levels were observed in the DE group. The millet SCM feeding showed pronounced ameliorating effects on kidney pathology as reflected by near normal glomerular and tubular structures and lower glomerular filtration rate compared with the shrunken glomerulus, tubular vacuolations in the DC group. Thus, the present animal study evidenced the hypoglycaemic, hypocholesterolaemic, nephroprotective and anti-cataractogenic properties of finger millet SCM, suggesting its utility as a functional ingredient in diets for diabetics.     

硫胺素、核黄素营养现况与中老年人抗氧化水平的相关性

目的分析硫胺素和核黄素营养状况与机体抗氧化水平及血糖、血脂水平的关系。方法选取上海市区314名中老年人作为调查对象,采用连续三日24小时膳食回顾法计算每日营养素摄入量,尿负荷实验测定机体硫胺素、核黄素营养水平,同时测定其血浆超氧化物歧化酶（SOD）活性、丙二醛（MDA）、空腹血糖（FBG）、总胆固醇（TC）和甘油三酯（TG）水平。结果膳食硫胺素平均摄入量为（0．82±0．36）mg／d,其中达到或超过推荐摄人量（RNI）的比例为11．8％,低于60％RNI的比例为51．3％;核黄素平均摄入量为（0．91±0．48）mg／d,其中达到或超过RNI的比例为17．2％,低于60％RNI的比例为49．4％。尿负荷实验结果显示,机体硫胺素缺乏的比例为65．0％,核黄素缺乏的比例为58．6％。与正常组相比,硫胺素、核黄素不足和缺乏组的MDA、FBG、Tc和TG水平呈升高趋势,SOD活性呈下降趋势,其中硫胺素缺乏组的MDA、FBG和Tc与正常组间差异有统计学意义（P〈0．05）。FBG、TC与尿硫胺素水平呈弱负相关（r=-0．246、r=-0．154,P〈0．05）,MDA、TG与尿核黄素水平呈弱负相关（r=-0．136、r=-0．297,P〈0．05）。结论上海部分地区中老年人硫胺素、核黄素营养水平较低,硫胺素、核黄素营养水平与机体抗氧化水平呈弱正相关趋势,与血糖、血脂水平呈弱负相关趋势。     

Multiple micronutrient supplements improve micronutrient status and anemia but not growth and morbidity of Indonesian infants: a randomized, double-blind, placebo-controlled trial

Multiple micronutrient deficiencies are highly prevalent in Indonesia, but the interventions are still focused on single micronutrients. This study aimed to investigate the efficacy of multiple micronutrient supplements for improving micronutrient status, anemia, growth, and morbidity of Indonesian infants. In this double-blind, placebo-controlled trial, 284 infants aged 6-12 mo were randomly allocated to 4 treatment groups for 23 wk; 260 (92%) infants completed the study. Group 1 (DMM) received one adequate intake of multiple micronutrient supplements daily (n = 66); group 2 (WMM) received 2 adequate intakes of multiple micronutrient on 1d plus 6 d of placebo (n = 60); group 3 (DI) received 10 mg of iron supplement daily (n = 69); group 4 received a placebo supplement daily (n = 65). Blood samples were collected at baseline and at posttreatment to assess anemia and micronutrient status. Anthropometric measurements were taken monthly, and morbidity was recorded daily. At baseline, 58.1% of infants were anemic, 34.2% were iron deficient, 21.3% were vitamin A deficient, and 11% were zinc deficient. The DMM and DI supplements both corrected iron deficiency, but DMM supplements were more efficacious in improving hemoglobin levels of anemic infants than the other supplements. However, anemia still persisted in one-third of DMM infants posttreatment. The DMM supplement was more efficacious than WMM or DI supplementation in improving infant status of other micronutrients, including zinc, tocopherol, and riboflavin, whereas DI exacerbated zinc deficiency. There were no significant differences in growth and morbidity among treatment groups, and growth faltering was not prevented.     

Effect of B vitamins-fortified foods on primary school children in Beijing

The objective of this study is to investigate the effect of B vitamins-fortified foods on primary school children. A controlled trial was conducted in 101 normal primary school children aged 9-11 years. They were randomly assigned to supplemental control group (S-control, n=36), riboflavin supplementation group (+riboflavin 0.625 mg/day, n=32), and B vitamin compound supplementation group (+riboflavin 0.625 mg/day, +thiamin 0.512 mg/day, +nicotinic acid 0.365 mg/day, +folic acid 0.13 mg/day, n=33) based on school classes. Urinary riboflavin excretion and erythrocyte glutathione reductase activity coefficient (EGRAC) along with erythrocyte transketolase activity (ETKA) were used to evaluate B vitamin levels in the children. AYP index, an index reflecting the brain performance ability, was chosen to assess the children's study abilities. Health education was carried out to help children and their parents adopt scientific dietary concepts. The urinary riboflavin excretion was higher in two supplementation groups (435.24 +/- 153.3 microg/g creatinine, 374.6 +/- 144.6 microg/g creatinine) than in S-control group (235.1 +/- 86.2 microg/g creatinine). Average values of EGRAC were lower in two supplementation groups (0.90 +/- 0.11, 0.80 +/- 0.10) than in S-control group (1.08 +/- 0.25). At the same time, the percentage of thiamine pyrophosphate (TPP%) decreased from 63.69 +/- 28.04 to 42.16 +/- 16.31 in B vitamin compound supplementation group. Meanwhile, AYP index increased at the end of the supplementation in two supplementation groups. B vitamins supplementation can significantly increase B vitamin level in children. Biochemical activities of riboflavin and thiamin can improve with the intake of fortified foods. The effect of B vitamin compound supplementation is better than that of single riboflavin supplementation when the effect of riboflavin's biofunction is considered. In addition, micronutrient supplementation appears to assist children's study abilities.     

Dietary fat intake and early age-related lens opacities

BACKGROUND: Dietary fat may affect lens cell membrane composition and function, which are related to age-related cataract. OBJECTIVE: The objective of the study was to examine the association between long-term dietary fat intake and the prevalence of age-related nuclear, cortical, and posterior subcapsular lens opacities. DESIGN: Women (n = 440) aged 53-73 y from the Boston area without previously diagnosed cancer, diabetes, or cataract were selected from the Nurses' Health Study cohort. Intakes of total fat and selected fatty acids were calculated as the average of intake data from 5 food-frequency questionnaires collected between 1980 and the study eye examination (1993-1995). Nuclear opacity was defined as grade >/=2.5, cortical opacity as grade >/=1.0, and posterior subcapsular opacity as grade >/=0.5 according to the Lens Opacities Classification System III. RESULTS: There were significant positive associations between linoleic and linolenic acid intakes and the prevalence of nuclear opacity. The odds ratios for nuclear opacity in women with intakes in the highest quartile and women with intakes in the lowest quartile were 2.2 (95% CI: 1.1, 4.6; P for trend = 0.02) for linoleic acid and 2.2 (95% CI: 1.1, 4.5; P for trend = 0.05) for linolenic acid. There were no significant associations between intakes of any type of fat and either cortical or posterior subscapular opacity. CONCLUSIONS: High intake of the 18-carbon polyunsaturated fatty acids linoleic acid and linolenic acid may increase the risk of age-related nuclear opacity. Further study is needed to clarify the relation between dietary fat and cataract risk.     

糖尿病性白内障超声乳化人工晶体植入术临床观察

目的:探讨糖尿病性白内障进行超声乳化联合人工晶体植入手术的临床效果.方法:选择28例(28眼)糖尿病性白内障行超声乳化联合人工晶体植入术,并设28例(28眼)非糖尿病性白内障行超声乳化联合人工晶体植入术为对照.糖尿病患者术前内分泌专科治疗,空腹血糖控制在8.3mmol/L以下.结果:糖尿病组患者术后并发症高于非糖尿病组,但经过正确处理,两组术后视力无明显差异.结论:糖尿病患者只要有效控制血糖,行白内障超声乳化联合人工晶体植入术是安全的,但术后血糖的控制十分重要.     

Apparent absorption of eight micronutrients and phytic acid from vegetarian meals in ileostomized human volunteers

OBJECTIVES: Apparent absorption of eight micronutrients and degradation of phytic acid were studied in human subjects who underwent ileostomy. The prominent factors affecting micronutrient absorption from vegetarian Indian meals (n = 11) were identified. METHODS: Levels of beta-carotene, ascorbic acid, riboflavin, and thiamine in food and ileostomy contents were estimated by spectrophotometry and spectrofluorometry. Contents of zinc, iron, copper, and manganese were estimated by atomic absorption spectrometry and that of phytic acid by gradient elution ion exchange chromatography. Statistical analyses were done with SPSS 10.0. RESULTS: Absorption of beta-carotene, ascorbic acid, riboflavin, and thiamine was 63% to 75.6%. There was a negative non-significant trend in values of beta-carotene absorption with increased intake of beta-carotene (r = - 0.51, P > 0.1) and iron (r = -0.67, P = 0.1) but a positive significant trend with riboflavin intakes (r = 0.84, P = 0.018). Percentage of absorption of ascorbic acid showed weak positive associations with intakes of riboflavin (r = 0.71) and ascorbic acid (r = 0.5). Percentage of absorption of ascorbic acid was positively correlated with percentage of absorption of beta-carotene (r = 0.80, P < 0.05), iron, and riboflavin (r = 0.64, P = 0.086), indicating some common influencing factors. Percentages of absorption for zinc (20.2), iron (9.9), and copper (17.6) was comparable with those reported for soy protein-based, high phytate diets. Pattern of phytic acid in the meals and output indicated partial degradation and absorption (34%). CONCLUSIONS: For vegetarian Indian meals, apparent absorptions of beta-carotene and ascorbic acid were 76% and 73.5% and of riboflavin and thiamine was 63%. Zinc, copper, and iron showed a lower absorption (10% to 20%).     

胰岛素抵抗及β-细胞敏感性与糖代谢异常的关系

目的探讨糖尿病前期和糖尿病相关的风险因子以及胰岛素抵抗与糖代谢异常的关系。方法对380例年龄在55～75岁不同血糖状态的城市社区居民进行空腹血糖与餐后血糖监测。分为正常血糖82人,糖尿病前期190人,糖尿病108人。对三组人群进行体格检查及血生化指标、胰岛素抵抗(HOMA-IR)及β-细胞敏感性(HOMA-β)等指标的检测。结果不同的血糖状态下甘油三酯(TG)、HOMA-IR、未调整以及经年龄、性别和体质指数(BMI)调整的HOMA-β、C-反应蛋白(CRP)均有统计学意义(P<0.01)。多变量Ordinal Logistic回归分析结果表明,HOMA-IR与HOMA-β是糖尿病前期及糖尿病的危险因子(P<0.01),总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)也与糖尿病前期及糖尿病相关。结论 HOMA-IR和HOMA-β与糖尿病前期及糖尿病有关。     

Cognitive impairment: an increasingly important complication of type 2 diabetes: the age, gene/environment susceptibility--Reykjavik study

Persons with type 2 diabetes are at increased risk of cognitive dysfunction. Less is known about which cognitive abilities are affected and how undiagnosed diabetes and impaired fasting glucose relate to cognitive performance. The authors explored this question using data from 1,917 nondemented men and women (average age = 76 years) in the population-based Age, Gene/Environment Susceptibility-Reykjavik Study (2002-2006). Glycemic status groups included diagnosed diabetes (self-reported diabetes or diabetic medication use; n = 163 (8.5%)), undiagnosed diabetes (fasting blood glucose >or=7.0 mmol/L without diagnosed diabetes; n = 55 (2.9%)), and impaired fasting glucose (fasting blood glucose 5.6-6.9 mmol/L; n = 744 (38.8%)). Composites of memory, processing speed (PS), and executive function were constructed from a neuropsychological battery. Linear regression was used to investigate cross-sectional differences in cognitive performance between glycemic groups, adjusted for demographic and health factors. Persons with diagnosed diabetes had slower PS than normoglycemics (beta = -0.12; P < 0.05); diabetes duration of >or=15 years was associated with significantly poorer PS and executive function. Undiagnosed diabetics had slower PS (beta = -0.22; P < 0.01) and poorer memory performance (beta = -0.22; P < 0.05). Persons with type 2 diabetes have poorer cognitive performance than normoglycemics, particularly in PS. Those with undiagnosed diabetes have the lowest cognitive performance.     

Efficacy of twice-weekly multiple micronutrient supplementation for improving the hemoglobin and micronutrient status of anemic adolescent schoolgirls in Bangladesh

BACKGROUND: Although iron deficiency is a major cause of anemia, other micronutrient deficiencies may also play a role. OBJECTIVE: We examined whether multiple micronutrient supplementation is more efficacious than is supplementation with iron and folic acid alone for improving the hemoglobin and iron status of anemic adolescent girls in Bangladesh. DESIGN: Anemic (hemoglobin < 12.0 g/dL) girls (n = 197) aged 14-18 y from rural schools in Dhaka District were entered into a randomized double-blind trial and received twice-weekly supplements of iron and folic acid (IFA group) or multiple micronutrients (15 micronutrients, including iron and folic acid; MMN group) for 12 wk. RESULTS: At recruitment, the characteristics of the girls in the 2 groups were not significantly different, except for family size and body mass index. At the end of the study, although both groups benefited significantly from supplementation, mean changes in hemoglobin and serum ferritin concentrations were not significantly different between groups. Compared with the IFA group, girls in the MMN group had significantly greater increases in mean serum vitamin A, plasma vitamin C, red blood cell folic acid, and riboflavin concentrations (assessed as erythrocyte glutathione reductase activation coefficient). After 12 wk of supplementation, only the prevalence of vitamins A and C and riboflavin deficiencies decreased more significantly in the MMN group than in the IFA group. CONCLUSIONS: Twice-weekly MMN supplementation for 12 wk significantly improved the status of the micronutrients assessed but was not more efficacious than was supplementation with iron and folic acid alone in improving the hematologic status of anemic adolescent girls. More frequent doses may be needed to achieve full benefit.     

Curcumin-supplemented yoghurt improves physiological and biochemical markers of experimental diabetes

We investigated the effects of prolonged treatment of diabetic rats with curcumin-supplemented yoghurt on the physiological and biochemical changes associated with diabetes mellitus. An established metabolic cage model was used to assess these changes in three groups of streptozotocin-diabetic rats which had been administered, by gavage, curcumin blended into yoghurt in the doses of 30, 60 and 90?mg/kg body weight (BW) per d (groups DC30, DC60, DC90) for 31?d. One group of non-diabetic rats was also treated with 90?mg/kg BW per d curcumin (NDC90). Three control groups of diabetic animals received water (DW), yoghurt (DY) and insulin at 27·78?μmol/d by subcutaneous injection (DI). Also, two groups of non-diabetic animals received water (NDW) and yoghurt (NDY). Groups DI and DC90 exhibited significant falls, relative to DW and DY, in food and water intake, urine volume, glycaemia, urinary urea and glucose, proteinuria, serum TAG and activities of aspartate and alanine aminotransferases, and higher hepatic glycogen and BW. These improvements were greater in DI than in DC90. No difference was observed in the serum levels of total cholesterol or HDL-cholesterol, or in the masses of adipose and muscular tissues, between DC90 and DW or DY. Moreover, the improvements in curcumin-treated rats, relative to DW and DY, were significant and dose-dependent. The NDC90 group also showed no difference from the NDW or NDY groups, in any of the markers for diabetes. In conclusion, curcumin mixed into yoghurt at the highest dose tested exhibited anti-diabetic activity, improving significantly most of the markers assessed in this study.     

盐城地区2型糖尿病患者自我管理小组活动效果评价及影响因素研究

目的 分析盐城地区2型糖尿病患者自我管理对空腹血糖及自我效能干预的效果,探讨影响空腹血糖改善的可能因素。方法 选择2018年盐城市部分街道和乡镇1 085名2型糖尿病患者作为研究对象。以调查问卷形式,对规范完成8次自我管理小组活动患者的空腹血糖、自我管理效果进行评价。结果 不同人口学特征糖尿病患者自我管理小组活动前后血糖改变情况比较,结果显示:以前是否参加过糖尿病管理小组(Z=-2.080,P=0.038)、糖尿病治疗方式(Z=-2.662,P=0.008),活动前后血糖差值差异有统计学意义;糖尿病患者自我管理小组活动后,研究对象在空腹血糖值(t=7.107,P=0.000)、自我效能(t=23.309,P=0.000)、行为方式得分(t=17.685,P=0.000)上与活动前相比,差异有统计学意义;多元线性回归分析结果显示,年龄(β=-0.107)、文化程度(β=-0.182)、糖尿病病史(β=0.121)、以往是否参加过自我管理小组活动(β=0.282)、行为方式得分(β=-0.091)是影响空腹血糖改善的因素(P＜0.05)。结论 开展糖尿病自我管理可以有效提升患者的自我效能和行为方式,改善患者空腹血糖状况。     

A prospective cohort study of exercise and the incidence of type 2 diabetes in impaired fasting glucose group

OBJECTIVES: To determine the relationship between exercise and the incidence of type 2 diabetes in an impaired fasting glucose group. METHODS: This prospective cohort study was conducted in 19,440 men and 4,297 women, aged 30-69 years, with impaired fasting glucose at baseline who had undergone biennial medical evaluation through the National Health Insurance Corporation from 2000 to 2004. Impaired fasting glucose was defined as fasting glucose of 100 to 125 mg/dl and the subjects were divided into 3 groups depending on weekly exercise frequency. Multivariate logistic regression analysis was used to evaluate the association between the baseline exercise status and incidence of type 2 diabetes. RESULTS: During the 4-year follow-up, a total of 3,239 men and 283 women developed type 2 diabetes, a cumulative incidence of 16.6% for men, and 6.5% for women. Also, 1,688 men (21.2%) and 127 women (15.2%) developed type 2 diabetes in the obese group. The adjusted relative risk (RR) of developing type 2 diabetes in non-exercising men was significantly higher than exercising men regularly (RR= 1.375, 95% CI=1.236-1.529)(p<0.0001), and the RR for non-exercising women was higher than exercising women regularly (RR=1.124, 95% CI=0.711-1.778). The RR for non-exercise men/women in the obese group was 1.571 (95% CI=1.351-1.827)(p<0.0001)/1.869(95% CI=0.846-4.130). CONCLUSIONS: Regular exercise is effective in preventing type 2 diabetes in people with impaired fasting glucose, and particularly in obese people. People with risk factors for diabetes should participate in a regular exercise program.     

瑞格列奈与格列吡嗪治疗2型糖尿病的疗效比较

目的：比较瑞格列奈和格列吡嗪治疗2型糖尿病的疗效差异。方法：将单纯饮食控制或加用盐酸二甲双胍药物治疗不满意的2型糖尿病86例患者随机分成瑞格列奈组46例和格列吡嗪组42例，疗程12周。监测两组治疗前及治疗后的空腹及餐后2h血糖，治疗前及治疗后12周糖化血红蛋白（HbA1C）、总胆固醇、甘油三脂和体重的变化，并观察有否低血糖等不良反应。结果：瑞格列奈和格列吡嗪对空腹血糖均有显著性下降，两药降低幅度无统计学意义（P〉0．05），而对餐后2h血糖的疗效高于格列吡嗪（P〈0．01），两药能明显降低HbA1C，但瑞格列奈疗效优于格列吡嗪（P〈0．05）。结论：瑞格列奈和格列吡嗪对空腹血糖均有显著性下降，但瑞格列奈控制餐后高血糖和HbA1C明显优于格列吡嗪。     

小檗碱辅助治疗糖尿病临床疗效分析

目的观察小檗碱辅助治疗糖尿病临床疗效。方法将80例糖尿病患者随机分为对照组和小檗碱组各40例，对照组给予常规控稍血糖的治疗，小檗碱组在对照组的基础上给予口服小檗碱辅助治疗：治疗前和治疗后3个月比较两组患者体重、腰围、臀围、BMI、糖化血红蛋白，空腹血糖、餐后2h血搪和血脂四项。结果与对照组比较，小檗碱组可以显著改善患者各项指标，并且差别具有统计学意义。结论小檗碱辅助治疗糖尿病疗效显著，并且安全性好，值得推广。     

Nutritional status in persons with and without senile cataract: blood vitamin and mineral levels

As part of an exploratory study of nutrition and senile cataract relationships between biochemical markers of nutritional status and senile cataract were examined in 112 subjects aged 40-70 y. Seventy-seven subjects had a cataract in at least one lens. Blood levels were determined for total carotenoids, vitamin A, vitamin D, vitamin E, vitamin C, riboflavin, thiamin, vitamin B-6, zinc, copper, selenium, and magnesium. Subjects were grouped into quintiles for each nutrient. Logistic regression was used to estimate the odds ratios (ORs) for cataract among subjects in the highest quintile and the middle three quintiles relative to subjects in the lowest quintile. ORs were adjusted for age, sex, race, and presence of diabetes. Results suggest that risk of cortical cataract was reduced for subjects in the highest quintile of vitamin D and total carotenoids and that persons with cataract may have lower levels of vitamin C and higher levels of vitamin B-6 and Se.     

The relationship between riboflavin and plasma total homocysteine in the Framingham Offspring cohort is influenced by folate status and the C677T transition in the methylenetetrahydrofolate reductase gene

Methylenetetrahydrofolate reductase (MTHFR) catalyzes the synthesis of 5-methyltetrahydrofolate, the methyl donor for remethylation of homocysteine to methionine. The C677T MTHFR polymorphism is associated with mild hyperhomocysteinemia, but only in the presence of low folate status. Because MTHFR contains flavin adenine dinucleotide (FAD) as a prosthetic group, riboflavin status may also influence homocysteine metabolism. The objective of this study was to examine the association between riboflavin status and fasting plasma total homocysteine (tHcy) concentration while also considering MTHFR C677T genotype and folate status. The study was conducted using fasting plasma samples (n = 450) from the fifth examination of the Framingham Offspring Study cohort. All persons with the TT genotype and age- and sex-matched sets of individuals with the CT and CC genotypes were selected for determination of plasma riboflavin and flavin mono- and dinucleotide levels. Plasma riboflavin was associated with tHcy concentrations, but the association was largely confined to persons with plasma folate <12.5 nmol/L and TT genotype. In these persons, the mean tHcy among individuals with riboflavin levels <6.89 nmol/L was 14.5 micromol/L, whereas the mean tHcy for those with riboflavin > or = 11 nmol/L was 11.6 micromol/L (P-trend <0.03). Plasma flavin nucleotides were unrelated to tHcy concentrations. Our data suggest that riboflavin status may affect homocysteine metabolism, but only in a small segment of the population who have both low folate status and are homozygotes for the MTHFR C677T mutation.     

Short-term ascorbic acid deficiency does not impair antioxidant status in lens of guinea pigs

We examined whether short-term ascorbic acid deficiency impairs antioxidant status in the lens of guinea pigs. Male guinea pigs aged 4 wk were given a scorbutic diet (20 g/animal per day) with and without ascorbic acid (400 mg/animal per day) in drinking water for 3 wk. The ascorbic acid-deficient group showed no lens opacity. The ascorbic acid-deficient group had 14% of serum ascorbic acid concentration, 6% of aqueous humor ascorbic acid concentration, and 18% of lens ascorbic acid content in the ascorbic acid-adequate group. There were no differences in the contents of lens reduced glutathione and thiobarbituric acid reactive substances, an index of lipid peroxidation, between the ascorbic acid-deficient and adequate groups, while the deficient group had higher lens vitamin E content than the adequate group. The ascorbic acid-deficient group had higher serum vitamin E concentration than the ascorbic acid adequate group, while there were no differences in the concentrations of serum reduced glutathione and tiobarbituric acid reactive substances between the deficient and adequate groups. These results indicate that short-term ascorbic acid deficiency does not impair antioxidant status in the lens of guinea pigs despite induction of severe ascorbic acid depletion in the tissue, which may result in no cataract formation.     

Effect of the magnetized water supplementation on blood glucose,lymphocyte DNA damage,antioxidant status,and lipid profiles in STZ-induced rats

This study investigated the effects of magnetized water supplementation on blood glucose, DNA damage, antioxidant status, and lipid profiles in streptozotocin (STZ)-induced diabetic rats. There were three groups of 4-week-old male Sprague-Dawley rats used in the study: control group (normal control group without diabetes); diabetes group (STZ-induced diabetes control); and magnetized water group (magnetized water supplemented after the induction of diabetes using STZ). Before initiating the study, diabetes was confirmed by measuring fasting blood glucose (FBS > 200 dl), and the magnetized water group received magnetized water for 8 weeks instead of general water. After 8 weeks, rats were sacrificed to measure the fasting blood glucose, insulin concentration, glycated hemoglobin level, degree of DNA damage, antioxidant status, and lipid profiles. From the fourth week of magnetized water supplementation, blood glucose was decreased in the magnetized water group compared to the diabetes group, and such effect continued to the 8th week. The glycated hemoglobin content in the blood was increased in the diabetes group compared to the control group, but decreased significantly in the magnetized water group. However, decreased plasma insulin level due to induced diabetes was not increased by magnetized water supplementation. Increased blood and liver DNA damages in diabetes rats did significantly decrease after the administration of magnetized water. In addition, antioxidant enzyme activities and plasma lipid profiles were not different among the three groups. In conclusion, the supplementation of magnetized water not only decreased the blood glucose and glycated hemoglobin levels but also reduced blood and liver DNA damages in STZ-induced diabetic rats. From the above results, it is suggested that the long-term intake of the magnetized water over 8 weeks may be beneficial in both prevention and treatment of complications in diabetic patients.