Relationship between total homocysteine, total cholesterol and creatinine levels in overt hypothyroid patients

Homocysteine and Glaucoma

Elevated levels of homocysteine (Hcy), a non-proteinogenic amino acid, may lead to a host of manifestations across the biological systems, particularly the nervous system. Defects in Hcy metabolism have been associated with many neurodegenerative diseases including glaucoma, i.e., the leading cause of blindness. However, the pathophysiology of elevated Hcy and its eligibility as a risk factor for glaucoma remain unclear. We aimed to provide a comprehensive review of the relationship between elevated Hcy levels and glaucoma. Through a systemic search of the PubMed and Google Scholar databases, we found that elevated Hcy might play an important role in the pathogenesis of glaucoma. Further research will be necessary to help clarify the specific contribution of elevated Hcy in the pathogenesis of glaucoma. A discovery and conceptual understanding of Hcy-associated glaucoma could be the keys to providing better therapeutic treatment, if not prophylactic treatment, for this disease.

Homocysteine-Potential Novel Diagnostic Indicator of Health and Disease in Horses

Homocysteine is an endogenous, non-protein sulfuric amino acid, an intermediate metabolite formed by the methionine transmethylation reaction. Its elevated serum concentration in humans, hyperhomocysteinemia, is a sensitive indicator and a risk factor for coagulation disorders, cardiovascular diseases and dementia. However, the role of homocysteine in veterinary species has not been unequivocally established. Although some research has been conducted in dogs, cats, cattle and pigs, relatively few studies on homocysteine have been conducted in horses. So far, it has been established in this species that homocysteine has an atherogenic effect, plays a role in early embryo mortality and is responsible for the induction of oxidative stress. These preliminary findings support establishing a reference range in a normal population of horses, including horses in training and merit further investigations into the role of this amino acid in health and disease in this species.

Prevalence and Determinants of Hypothyroidism in Patients on Routine Hemodialysis in Somalia: A Cross-Sectional Study

Introduction

In recent decades, the relationship between thyroid and kidney disease has drawn considerable attention. We aim to assess the prevalence and the determinants of hypothyroidism in hemodialysis patients in Somalia.

Materials and Methods

This is a cross-sectional study which was conducted in the hemodialysis unit of Mogadishu Somalia Turkish Training and Research Hospital, between June 1 and July, 31 2022. A total of 301 patients who are routinely going to hemodialysis were included in the study. Demographic data including age, gender, and data regarding hemodialysis were extracted from hospital information system (HIS). All participants had their thyroid function test measured before hemodialysis sessions.

Results

A total of 301 patients were examined. Their ages ranged from 40 to 66 years, with the median age being 54 (IQR= 40-66). Males were 167 (55.5%) compared to females 134 (44.5%). Hypertension was the most common comorbidity among the patients with 137 (45.5%). Diabetic kidney disease was the most common cause of renal failure in 138 patients (45.84%) followed by hypertensive kidney disease 100 (33.22%). The prevalence rate of hypothyroidism in hemodialysis patients in our study was 28%. In hypothyroidism patients 57.8% had subclinical hypothyroidism and 42.2% had overt hypothyroidism. 70.8% of our patients were in euthyroid status. Subclinical hypothyroidism was commonly seen in patients with diabetes, hypertension, and heart disease. We found that increasing age, decreased albumin level were related to higher risk of subclinical hypothyroidism. We also found that increasing creatinine levels were associated with lower risk of overt hypothyroidism.

Conclusion

The prevalence rate of hypothyroidism in hemodialysis patients was 28%, with 57.8% showing subclinical hypothyroidism and 42.2% overt hypothyroidism. Increased age and low albumin level was associated with the prevalence of subclinical hypothyroidism in hemodialysis patients. Also low creatinine level was observed in overt hypothyroidism patients.

Association of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms (C677T and A1298C) with thyroid dysfunction: A meta-analysis and trial sequential analysis

Recent studies have shown that two common methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms (C677T and A1298C) might correlate with thyroid dysfunction, but the results remain inconsistent. We carried out a meta-analysis aiming to assess the relationship of both polymorphisms with thyroid dysfunction. The PubMed, EMBASE, CNKI (China National Knowledge Infrastructure), CBMdisc (China Biology Medicine disc), WeiPu and Wanfang databases were searched up to September 2021. Case-control and cohort studies on MTHFR polymorphism and thyroid dysfunction were identified. Eight studies from six publications were finally included in our meta-analysis, including 817 patients and 566 controls. After pooled analysis, we found that the MTHFR C677T polymorphism was associated with an increased risk of hypothyroidism (TT vs. CC+CT/recessive model: OR = 2.07, 95% CI: 1.02-4.20, P = 0.04; TT vs. CC/homozygote model: OR = 2.35, 95% CI: 1.13-4.86, P = 0.02), while trial sequential analysis (TSA) revealed that it could be a false positive result. The MTHFR A1298C polymorphism was related to a decreased risk of hypothyroidism (C vs. A/allele model: OR = 0.63, 95% CI: 0.44-0.92, P = 0.02; CC vs. AC+AA/recessive model: OR = 0.42, 95% CI: 0.22-0.79, P = 0.007; CC vs. AA/homozygote model: OR = 0.43, 95% CI: 0.25-0.85, P = 0.02), which was conclusive according to TSA. The results of this meta-analysis suggest that MTHFR A1298C seems to be a protective factor for hypothyroidism, while the MTHFR C677T polymorphism may be a risk factor. However, more well-designed studies with larger sample sizes are needed to obtain more reliable results of the association between the MTHFR C677T polymorphism and hypothyroidism.

Homocysteine, Vitamins B6 and Folic Acid in Experimental Models of Myocardial Infarction and Heart Failure—How Strong Is That Link?

Cardiovascular diseases are the leading cause of death and the main cause of disability. In the last decade, homocysteine has been found to be a risk factor or a marker for cardiovascular diseases, including myocardial infarction (MI) and heart failure (HF). There are indications that vitamin B6 plays a significant role in the process of transsulfuration in homocysteine metabolism, specifically, in a part of the reaction in which homocysteine transfers a sulfhydryl group to serine to form α-ketobutyrate and cysteine. Therefore, an elevated homocysteine concentration (hyperhomocysteinemia) could be a consequence of vitamin B6 and/or folate deficiency. Hyperhomocysteinemia in turn could damage the endothelium and the blood vessel wall and induce worsening of atherosclerotic process, having a negative impact on the mechanisms underlying MI and HF, such as oxidative stress, inflammation, and altered function of gasotransmitters. Given the importance of the vitamin B6 in homocysteine metabolism, in this paper, we review its role in reducing oxidative stress and inflammation, influencing the functions of gasotransmitters, and improving vasodilatation and coronary flow in animal models of MI and HF.

Gender- and age-related differences in homocysteine concentration: a cross-sectional study of the general population of China

The primary goals of this study were to evaluate the gender- and age-related differences in homocysteine concentration in the general population of China and possible influencing factors. A total of 7872 subjects, divided into male and female groups, participated in this retrospective study. The average homocysteine level, prevalence of hyperhomocysteinemia, and independent factors affecting homocysteine concentration were analyzed. The homocysteine level was significantly higher in males than in females in each age range (aged 20–30, aged 30–40, aged 40–50, aged 50–60, aged 60–80, aged over 80) (P < 0.0001), and the trend did not abate with age. The homocysteine concentration first decreased and then increased, being lowest at 30–50 years of age and significantly increased after 50 years of age. Factors associated with homocysteine concentration in males were smoking status (current smokers versus ex-smokers: β: 0.112), estimated glomerular filtration rate (β =  − 0.192), blood urea nitrogen (β =  − 0.14), diastolic blood pressure (β =  − 0.113), free triiodothyronine (β =  − 0.091), serum potassium (β =  − 0.107) and cystatin C (β = 0.173). In females, independent factors associated with homocysteine concentration were cystatin C (β = 0.319), albumin (β = 0.227), free thyroxine (β = 0.179), age (β = 0.148), free triiodothyronine (β =  − 0.217) and serum potassium (β =  − 0.153). The homocysteine level was significantly higher in males than in females and increased markedly after 50 years of age in both groups. The independent factors associated with increased homocysteine concentration differed between males and females.

Hyperhomocysteinemia: Clinical Insights

Homocysteine (Hcy) is a sulfhydryl-containing amino acid, and intermediate metabolite formed in metabolising methionine (Met) to cysteine (Cys); defective Met metabolism can increase Hcy. The effect of hyperhomocysteinemia (HHcy) on human health, is well described and associated with multiple clinical conditions. HHcy is considered to be an independent risk factor for common cardiovascular and central nervous disorders, where its role in folate metabolism and choline catabolism is fundamental in many metabolic pathways. HHcy induces inflammatory responses via increasing the pro-inflammatory cytokines and downregulation of anti-inflammatory cytokines which lead to Hcy-induced cell apoptosis. Conflicting evidence indicates that the development of the homocysteine-associated cerebrovascular disease may be prevented by the maintenance of normal Hcy levels. In this review, we discuss common conditions associated with HHcy and biochemical diagnostic workup that may help in reaching diagnosis at early stages. Furthermore, future systematic studies need to prove the exact pathophysiological mechanism of HHcy at the cellular level and the effect of Hcy lowering agents on disease courses.

Association Between Plasma Homocysteine Levels and Subclinical Hypothyroidism in Adult Subjects: A Meta-Analysis

Increased plasma homocysteine (Hcy) levels have been widely documented in patients with overt hypothyroidism; however, the significance of Hcy level changes in patients with subclinical hypothyroidism (SCH) remains controversial. The aim of this meta-analysis was to determine the Hcy status in patients with SCH compared with euthyroid subjects. We searched PubMed, Embase, and Cochrane Library databases prior to December 2019 to identify eligible studies and assessed the quality of selected studies using the Newcastle-Ottawa Quality Assessment Scale. Publication bias was evaluated by Begg's test and Egger's test. Meta-regression analysis was conducted to investigate the source of heterogeneity. A likely source of heterogeneity was the year of the study. All statistical analyses were performed with RevMan 5.3 and Stata 12.0 software. Our meta-analysis of twelve observational studies with 684 patients showed that those with SCH aged between 18 and 65 years old were associated with a slightly increased plasma Hcy level compared with euthyroid controls. The pooled result of the weighted mean difference (WMD) of increased tHcy levels was 1.16 μmol/l (95% CI: 0.51, 1.82; p=0.0005). The Hcy level in patients with SCH aged between 18 and 65 years old is significantly increased compared to euthyroid controls.

S, Dande P. Protective effect of a polyherbal bioactive fraction in propylthiouracil-induced thyroid toxicity in ratsby modulation of the hypothalamic-pituitary-thyroid and hypothalamic-pituitary-adrenal axes

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Hypothyroidism is the most frequent toxic effect of a large variety of chemical compounds.

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The polyherbal bioactive fraction exhibited a pro-thyroid effect in hypothyroidic rats.

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The polyherbal fraction restored the propylthiouracil-depleted thyroid hormone levels significantly.

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The polyherbal fraction may act through multiple mechanisms to exhibit a pro-thyroid effect.

Hypothyroidism is the most frequent consequence of the interaction of a large variety of drugs, environmental pollutants and industrial chemicals with the thyroid gland. It is associated with diminished endocrine function which may lead to hyperlipidemia, diabetes, Alzheimer’s disease, weight gain, and other metabolic disorders. The present study evaluates the pro-thyroid activity of a bioactive fraction from a polyherbal teabag in rats with hypothyroidism induced by propylthiouracil. The teabag was formulated to stimulate synthesis and/or release of T4 and affectthe conversion of T4 to T3. Phytoconstituents of the polyherbal teabag are potent antioxidants that may be responsible for the pro-thyroid activity. The tea-extract (1000 mg) was found to contain 1076 μg of gallic acid and 1131 μg of rutin from HPTLC analysis. Rats received propylthiouracil (8 mg/kg) for the first 15days followed by the polyherbal tea-extract (500, 1000 and 1500 mg/kg), the standard drug levothyroxine (0.1 mg/kg), aerobic exercise, and a combination of tea-extract (1000 mg/kg) and aerobic exercise daily along with propylthiouracil for the next 30 days. Finally, rats received their respective treatments alone without propylthiouracil for 15 more days. Lipid profile and levels of glucose, insulin, T3, T4, TSH, cortisol, homocysteine, creatinine, uric acid, malondialdehyde, glucose-6 phosphatase, and endogenous antioxidants were determined. All treatments attenuated significantly the propylthiouracil-elevated TSH, homocysteine, creatinine, uric acid, glucose-6-phosphatase, insulin, and malondialdehyde levels, and restored favorably the propylthiouracil-altered lipid profile, T3, T4, and endogenous antioxidant levels. The polyherbal tea-extract (1000 and 1500 mg/kg) treatment and thecombination treatment of tea-extract (1000 mg/kg) with aerobic exercise displayed significant restoration of the suboptimalthyroid function. This may be due to a favorablemodulation ofthe hypothalamic-pituitary–thyroid and the hypothalamic–pituitary–adrenal axes.

A hidden cause of infertility in hypothyroid patients

Methylene tetrahydrofolate reductase (MTHFR) gene mutations could be the cause of infertility in hypothyroid patients. Hence, it is worthy to screen for MTHFR gene mutations in infertile hypothyroid females and their partners if infertility persists after optimizing thyroid function.

Metabolic distress in lipid & one carbon metabolic pathway through low vitamin B-12: a population based study from North India

Background

Dyslipidemia and hyper-homocysteinemia are the major independent risk factors of cardio vascular disease. Deficiency of folate and vitamin B-12 are associated with both hyper-homocysteinemia and dyslipidemia. The aim of the study is to evaluate the relationship of homocysteine and its associated dietary determinant levels (Folate and Vitamin B-12) with lipids and obesity parameters (WC, BMI, WHR) in North Indian population.

Methods

The participants were recruited under a major government funded project through household survey covering 15 villages of Haryana, India. Participants were both males and females, between age group 30–65 years, from a north Indian community. Initially 1634 individuals were recruited, of which 1374 were considered for analysis as they were not found to be on any kind of medication for high blood pressure, CAD, diabetes or any other disorder, and had no missing data. 5 mL of intravenous blood sample was collected after obtaining written informed consent from the participants. Homocysteine, folate and vitamin B12 levels were estimated through Immulite 1000 by chemi-luminescence technique. Triglyceride, total cholesterol and HDL-C were estimated by spectrophotometry technique using commercial kits. The values for LDL and VLDL were calculated using Friedwald’s equation. Height, weight, waist circumference (WC), hip circumference (HC) was measured over light clothing. Statistical analysis for data was performed using SPSS 16.0 version.

Results

All the lipid indices, except HDL, showed a trend of negative correlation with homocysteine after controlling for confounders, though not significant. No association was found between obesity (WC, BMI, WHR) and homocysteine in the present study. Vitamin B-12 deficiency was significantly associated with both hyper-homocysteinemia and low HDL. Folate was found to have significantly reduced risk for high TC & LDL.

Conclusions

The “hcy-lipid” hypothesis does not seem to be complementing in the present studied population. The population is vulnerable to severe under-nutrition due to the association of vitamin B-12 with HDL, leading to metabolic disturbance in both the pathways; lipid and one carbon metabolic pathway. Co-factors such as ethnicity, cultural practices, and lifestyle & dietary habits must be considered while making public health policies to control diseases.

Electronic supplementary material

The online version of this article (10.1186/s12944-018-0748-y) contains supplementary material, which is available to authorized users.

Causes of hyperhomocysteinemia and its pathological significance

In the last 10 years, homocysteine has been regarded as a marker of cardiovascular disease and a definite risk factor for many other diseases. Homocysteine is biosynthesized from methionine through multiple steps and then goes through one of two major metabolic pathways: remethylation and transsulfuration. Hyperhomocysteinemia is a state in which too much homocysteine is present in the body. The main cause of hyperhomocysteinemia is a dysfunction of enzymes and cofactors associated with the process of homocysteine biosynthesis. Other causes include excessive methionine intake, certain diseases and side effects of some drugs. Hyperhomocysteinemia is a trigger for many diseases, such as atherosclerosis, congestive heart failure, age-related macular degeneration, Alzheimer's disease and hearing loss. There are many studies showing a positive relationship between homocysteine level and various symptoms. We speculate that a high level of homocysteine can be the sole reason or an aggravating factor in numerous diseases for which causal links are not fully understood.

Serum levels of nitrite/nitrate, lipid profile, and Fasting Plasma Glucose and their associations in subclinical hypothyroid women before and after a two month treatment by levothyroxine

BACKGROUND

Subclinical hypothyroidism (sHT) is a condition defined by elevated TSH values with normal levels of free thyroid hormones. Altered metabolic status is one of the consequences of sHT which can affect serum levels of FPG, lipid profile, and nitric oxide which propounds cardiovascular consequences per se. The aim of this study was to determine the possible effects of sHT on nitrite/nitrate levels, as a marker of endothelial performance.

MATERIALS AND METHODS

50 females were enrolled in this study, 25 women as control group and 25 women as case group (evaluated two times: before and after levothyroxine therapy). Blood samples were collected and levels of FPG, lipid profile components, and nitric oxide were measured spectrophotometrically. The data were analyzed using SPSS version 18 software.

RESULTS

The levels of lipid profile (except for TG between before and after group, p < 0.05) and nitric oxide did not differ in groups while FPG was significantly higher in case groups in comparison to control group (p < 0.001). Nitric oxide had no correlations with any of variables except for LDL in after treatment group (p < 0.05 and r = 0.397).

CONCLUSION

Nitric oxide does not have correlation with components of lipid profile (except for LDL) or FPG and has no differences in subclinical hypothyroid patients and control group. Levothyroxine therapy during 2 months cannot alter the levels of nitric oxide in subclinical hypothyroid patients.

Relationship between Total Homocysteine, Folic Acid, and Thyroid Hormones in Hypothyroid Dogs

Background

Both elevated homocysteine and decreased folic acid concentrations are observed in human patients with hypothyroidism and can influence the development of numerous secondary disorders.

Objectives

The aim of the study was to assess total homocysteine concentration in serum and to examine its relationship with the concentration of folic acid and thyroid hormones (tT4 and fT4).

Animals

Ten healthy and 19 hypothyroid client‐owned dogs.

Methods

Dogs with clinical signs of hypothyroidism had the diagnosis confirmed by additional tests. Total homocysteine, folic acid, total thyroxine, and free thyroxine concentrations in serum were evaluated.

Results

Hypothyroid dogs were diagnosed with increased homocysteine (median 22.20 μmol/L; range, 16.50–37.75) and decreased folic acid (median 20.62 nmol/L; range, 10.54–26.35) concentrations, as compared to healthy dogs (11.52 μmol/L; range, 10.00–16.65 and 30.68 nmol/L; range, 22.84–38.52, respectively). In sick dogs, total homocysteine was inversely correlated with folic acid (ρ = −0.47, P < 0.001), total thyroxine (ρ = −0.69, P = 0.0092), and free thyroxine (ρ = −0.56, P = 0.0302).

Conclusions

Hypothyroidism in dogs causes hyperhomocysteinemia. Concomitant mild folic acid decrease in hypothyroid dogs might be as a result of hyperhomocysteinemia.

Delirious Mania Associated with Autoimmune Gastrothyroidal Syndrome of a Mid-Life Female: The Role of Hashimoto Encephalopathy and a 3-Year Follow-Up including Serum Autoantibody Levels

We report the case study of a 57-year-old Caucasian female with steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT), commonly termed Hashimoto encephalopathy (HE). This presentation includes one of the longest lasting follow-up studies of HE considering the neuropsychiatric symptoms (here delirium, mania, and EEG-slowing) and their relation to serum autoantibody levels. Antithyroid-peroxidase autoantibodies, the hallmark of autoimmune thyroiditis, were found in the serum and also in the cerebrospinal fluid. Diagnostic analyses found no evidence of limbic encephalopathies characterized by serum antibodies against intracellular, synaptic, or further cell surface antigenic targets, neoplasm, and connective tissue or vasculitis diseases. A potential contribution of bipolar disorder and metabolic encephalopathies due to severe hypothyroidism, glucocorticoid treatment, accelerated thyroid hormone replacement therapy, or vitamin B deficiency is critically discussed. Another special feature of this case report is the linkage of HE to an autoimmune polyendocrine syndrome (type 3B) affecting the gastroduodenum in addition to the thyroid gland.

Homocysteine diminishes apolipoprotein A-I function and expression in patients with hypothyroidism: a cross-sectional study

Background

Hypothyroidism (HO) can significantly impair lipid metabolism and increase cardiovascular disease risk. Hyperhomocysteinemia (HHcy) is an independent risk factor for cardiovascular disease. Our previous study demonstrated that HHcy significantly induced insulin resistance and impaired coronary artery endothelial function in patients with either hypertension or HO. In the present study, we studied whether plasma levels of high-density lipoprotein-cholesterol (HDL-C) and apolipoprotein A-I (Apo A-I) were altered in patients with HO, and if so, whether this change was mediated by HHcy.

Methods

A total of 258 subjects were enrolled and divided into the following three groups: control group (n = 94), HO group (n = 73), and subclinical hypothyroidism (SHO) group (n = 91). Additionally, all groups were subdivided based on the subjects’ Hcy levels into HHcy (plasma Hcy level over 15 μmol/l) and normal Hcy subgroups. The plasma levels of lipid indexes were measured. Statistical analyses were performed to evaluate the correlations between groups.

Results

The plasma Hcy levels were significantly higher in the HO group than in the SHO or control groups (all p < 0.05). Moreover, levels of Apo A-I and HDL-C were markedly reduced in the HHcy subgroup compared with the normal Hcy subgroup for patients with either HO (Apo A-I: p < 0.05; HDL-C: p < 0.01) or SHO (Apo A-I: p < 0.05; HDL-C: p < 0.01). In addition, the plasma Hcy levels were negatively correlated with levels of Apo A-I in all three groups (HO group: r = − 0.320, SHO group: r = − 0.337 and control group: r = − 0.317; all p < 0.01).

Conclusions

Hcy levels were significantly increased in patients with HO or SHO. These increased Hcy levels may impair cardiovascular function via the inhibition of Apo A-1 expression and impairment of its antioxidant capacity. Our findings provide new insights into the pathogenesis of hypothyroidism-induced metabolic disorders.

Potential harmful correlation between homocysteine and low-density lipoprotein cholesterol in patients with hypothyroidism

OBJECTIVE

Hypothyroidism (HO) can induce metabolic dysfunctions related to insulin resistance and dyslipidemia. Our previous studies showed that homocysteine (Hcy) impaired the coronary endothelial function and that Hcy can promote chemokine expression and insulin resistance (IR) by inducing endoplasmic reticulum stress in human adipose tissue and hypothyroid patients. The aim of this study was to investigate the potential harmful correlation between plasma Hcy and low-density lipoprotein cholesterol (LDL-C) in patients with HO.

METHODS

A total of 286 subjects were enrolled. All subjects were divided into the following 3 groups: HO group, subclinical hypothyroidism (SHO) group, and control group. Statistical analyses were carried out to evaluate the correlation between the plasma levels of Hcy and LDL-C in HO patients. The changes in the plasma Hcy levels and other metabolic parameters were measured before and after levothyroxine (L-T4) treatment. The relationship between the changes in the plasma Hcy level and the LDL-C level was also evaluated after L-T4 treatment.

RESULTS

In the patients with HO, both the plasma Hcy and LDL-C levels were significantly higher than those of the controls. The plasma levels of Hcy were positively correlated with the LDL-C level in the HO group. L-T4 treatment resulted in a significant decrease in the BMI, total cholesterol (TC), LDL-C, triglycerides (TG), apolipoprotein B (ApoB), and Hcy levels. Moreover, the decrease in Hcy (ΔHcy) was positively correlated with decreased LDL-C (ΔLDL-C) levels after L-T4 treatment in HO patients.

CONCLUSION

Our results suggest that the increased Hcy level was positively correlated with the LDL-C in the HO group. A potential harmful interaction may exist between Hcy and LDL-C under the HO condition. In addition to reducing the plasma levels of Hcy, L-T4 treatment exerts beneficial effects on patients with HO by improving dyslipidemia, including a decrease in the LDL-C level.

Association between Hyperhomocysteinemia and Thyroid Hormones in Euthyroid Diabetic Subjects

Objectives. The concept now emerging is that higher thyroid-stimulating hormone (TSH) and lower thyroid hormone levels within the euthyroid range may adversely affect atherosclerosis. The present study aimed to investigate the potential associations between thyroid parameters and hyperhomocysteinaemia in a cohort of euthyroid diabetic subjects. Material and Methods. Two hundred and seventy-three euthyroid diabetic subjects (167 males and 106 females) were consecutively recruited in this cross-sectional study. Clinical and biomedical data was collected. Results. TSH level was higher in females than males. Compared to normal-homocysteine group, hyperhomocysteinaemia group was more likely to be elderly, males, with longer diabetes history, and with lower diastolic blood pressure. Free thyroxine (FT4) level was lower in hyperhomocysteinaemia group than in normal-homocysteine group; however, it was not statistically significant. Adjusted for age, sex, body mass index, duration of diabetes, blood pressure, fasting glucose, total cholesterol, and triglyceride in logistic regression analyses, hyperhomocysteinaemia was significantly correlated with FT4 (P = 0.021). No significant association was found with TSH or free triiodothyronine. When analyzed in subjects with TSH < 2.5 uIU/mL separately, we got similar results. Conclusions. In conclusion, we identified a relation between hyperhomocysteinemia and FT4 in a group of euthyroid diabetic patients.

Serum Homocysteine and Total Antioxidant Status in Vitiligo: A Case Control Study in Indian Population

BACKGROUND

Oxidative stress is considered as an initial pathogenic event in melanocyte destruction. These free radicals are scavenged by antioxidants, whose sum of activity in serum is measured by total antioxidant status (TAS). In addition, homocysteine (Hcy) may mediate melanocyte destruction via increased oxidative damage. However, previous studies investigating these parameters in vitiligo provide equivocal results.

AIMS

To study and compare serum Hcy and TAS levels in vitiligo patients with controls and also to correlate these parameters with the various disease characteristics. The present study further looked into any correlation between serum Hcy and TAS in vitiligo.

MATERIALS AND METHODS

A case control study was conducted on 82 vitiligo patients and 83 controls aged 18-45 years after excluding factors which could potentially alter serum Hcy or TAS levels. Disease characteristics were studied and blood samples were obtained for measuring serum Hcy and TAS levels.

RESULTS

TAS levels were lower in vitiligo patients than controls (1.79 ± 0.51 vs. 2.16 ± 0.63 mmol/L; P < 0.001) and had a negative correlation with disease activity (r = -0.410, P < 0.001). However, serum Hcy levels were comparable between vitiligo patients (18.68 ± 9.90 μmol/L) and controls (20.21 ± 13.39 μmol/L) (P = 0.406). No significant correlation was found between serum Hcy and serum TAS levels.

CONCLUSIONS

Serum TAS may be further investigated to establish its role as biomarker for vitiligo since its levels also correlate with disease activity. However, serum Hcy may not be a reliable marker in Indian population probably because of differences in dietary habits.

Novel Clinical Evidence of an Association between Homocysteine and Insulin Resistance in Patients with Hypothyroidism or Subclinical Hypothyroidism

Objective

Hypothyroidism (HO) can induce significant metabolic dysfunction and increase cardiovascular disease risk. In the present study, we investigated the relationship between homocysteine (Hcy) and insulin resistance (IR) in patients with HO or subclinical hypothyroidism (SHO).

Methods

A total of 270 subjects were enrolled. All subjects were divided into the following three groups: HO, SHO and control. Plasma levels of Hcy were measured, and each patient’s homeostatic index of insulin resistance (HOMA-IR) was calculated. Statistical analyses were carried out to evaluate the correlations among groups and to determine the predictors of IR in patients with HO or SHO.

Results

The HOMA-IR value was significantly higher in the HO group than in the SHO and control groups. Plasma levels of Hcy were markedly increased in the HO group compared with those of the SHO group and controls. In addition, plasma levels of Hcy were positively correlated with the HOMA-IR values in both the HO and SHO groups. Multiple linear regression models showed that plasma levels of Hcy and free thyroxine (FT4) were the only predictors of HOMA-IR in patients with HO or SHO.

Conclusions

Plasma levels of Hcy and HOMA-IR were increased in patients with HO or SHO. Our results suggest that HO and SHO may increase the risk for atherogenesis and cardiovascular disease by increased IR. The increased IR induced by hyperhomocysteinemia in patients with HO or SHO may partially explain this adverse effect.

Homocysteine as a potential biomarker in bipolar disorders: a critical review and suggestions for improved studies

INTRODUCTION

Homocysteine levels have been associated with major depression, but associations with bipolar disorder remain less clear. Some data suggest homocysteine levels have potential as a biomarker of treatment response; however the literature is mixed.

AREAS COVERED

Oxidized forms of homocysteine can be potentially neurotoxic leading to glutamate toxicity, apoptotic transformation and neurodegenerative processes. High homocysteine may be a risk biomarker for bipolar disorders, but the empirical base remains too weak for firm conclusions. This review discusses the current literature for homocysteine levels as a biomarker.

EXPERT OPINION

It is premature to foreclose the utility of homocysteine levels as a biomarker for bipolar disorder due the methodological inadequacies in the existing literature. These methodological design issues include lack of control for the confounding variables of concurrent medication, phase of bipolar disorder, gender, age, nutritional status, thyroid, liver and renal function, smoking or lean body mass. Well-powered association studies with confounder control could help shed more light on the important clinical question of homocysteine's utility as a biomarker in bipolar disorder. Future experiments are needed to examine the outcome of interventions modulating homocysteine for treating bipolar disorder. Only prospective randomized control trials will provide definitive evidence of the utility of homocysteine as a biomarker or therapeutic target.

Association between plasma homocysteine status and hypothyroidism: a meta-analysis

PURPOSE

To figure out plasma homocysteine (Hcy) status in patients with subclinical hypothyroidism (SH) and overt hypothyroidism (OH) compared with healthy subjects, and the effect of levothyroxine (L-T4) on plasma homocysteine status in patients with hypothyroidism.

METHODS

PubMed Web of Science, and The Cochrane Library were used to identify eligible studies. The Newcastle-Ottawa Quality Assessment Scale was used to assess the quality of selected studies. All analyses were performed using the STATA, version 12 software.

RESULTS

Our meta-analysis indicated that plasma Hcy concentrations elevated in OH patients without L-T4 treatment compared with healthy subjects. However, this elevation was not observed in the comparison between patients withSH without L-T4 treatment and healthy subjects. Moreover, plasma Hcy levels were found to be higher in patients with OH without L-T4 treatment than in patients with SH without L-T4 treatment. Finally, plasma Hcy concentrations decreased after L-T4 treatment in patients with SH or OH.

CONCLUSIONS

Plasma Hcy status is associated with the severity of hypothyroidism and L-T4 treatment is helpful for patients with hypothyroidism to reduce the plasma Hcy levels.

Serum H-FABP levels in patients with hypothyroidism

OBJECTIVE

Hypothyroidism (HT) has an increased risk for cardiovascular mortality and morbidity due to increased atherosclerosis. Heart-type fatty acid binding protein (H-FABP) is abundant in the cytosol of cardiomyocytes, and transports fatty acids into these cells. Although H-FABP has been shown to increase in several atherosclerotic and inflammatory conditions, there is no literature data indicating an alteration in other atherosclerotic processes such as HT.

MATERIAL AND METHODS

A total of 39 patients with subclinical hypothyroidism (SCH), 26 patients with overt hypothyroidism (OH), and 29 healthy subjects were enrolled in this study. Carotid artery intima media thickness (CIMT) was measured by high resolution B mode ultrasonography. H-FABP levels, thyroid function test, and biochemical tests of all subjects were measured. The associations between H-FABP and thyroid test and CIMT were examined with correlation and regression analysis.

RESULTS

OH patients had higher H-FABP levels (mean, 6.18 ± 3.08 ng/mL) than both the SCH (mean, 3.81 ± 2.16 ng/mL) and the controls (mean, 2.12 ± 1.27 ng/mL) (P < 0.01 and < 0.001, respectively). SCH patients had increased serum H-FABP levels compared with control subjects (P < 0.01). CIMT of both OH and SCH patients was also significantly greater compared with control subjects (both of p < 0.01). H-FABP was significantly and positively correlated with age, systolic blood pressure, thyroid stimulating hormone (TSH) levels, and CIMT, and negatively correlated with fT4 levels. The H-FABP levels retained an independent and positive association with systolic blood pressure, and a negative association with fT4 levels.

CONCLUSION

Serum H-FABP levels progressively increased from the control group to the OH group. This suggests that H-FABP may be an indicator of low-level myocardial damage in HT, especially when used together with CIMT. Decreasing serum fT4 levels seem also to have an effect on H-FABP levels.

High prevalence of aspirin resistance in elderly patients with cardiovascular disease (CVD) and hyperhomocysteinaemia

Although aspirin resistance is well reported in CVD, little is known about aspirin response in elderly patients with hyperhomocysteinaemia. The aim of the present study was to explore the prevalence of aspirin resistance in elderly patients with CVD and hyperhomocysteinaemia. A total of 370 elderly patients with CVD were recruited. The study included 216 patients with hyperhomocysteinaemia and 154 patients with normohomocysteinaemia receiving daily aspirin therapy (≥ 75 mg) over 1 month. The effect of aspirin was assessed using by light transmission aggregometry (LTA). Aspirin resistance was defined as ≥ 20% arachidonic acid induced aggregation according to LTA. Aspirin resistance was defined in 48 (13.0%) of 370 patients. The prevalence of aspirin resistance was higher in hyperhomocysteinaemic patients than normohomocysteinaemic patients (16.7% vs. 7.8%, odds ratio (OR)=2.367; 95% confidence interval (CI)=1.188-4.715, p=0.012). In the multivariate logistic regression analysis, hyperhomocysteinaemia (OR=2.406, 95% CI=1.201-4.820, p=0.013) was a significant risk factor for aspirin resistance. A significant number of CVD patients with hyperhomocysteinemia are resistant to aspirin therapy. Hyperhomocysteinemia is a significant risk factor for aspirin resistance in elderly patients with CVD.