Alteration of ischemia modified albumin and nitric oxide levels in hypothyroidism

Status of Ischemia Modified Albumin in Athletes Before and After Moderate Exercise

Background:

Ischemia Modified Albumin (IMA) is considered as an early marker of ischemia. Its levels may be altered in any clinical condition where an ischemic event is involved. Skeletal muscle ischemia is associated with severe exercise but may also occur in moderate form of exercise.

Objective:

The levels of IMA were estimated before and after thirty minutes of moderate exercise in students undergoing athletic training.

Methods:

The present study was conducted on 120 young adult students undergoing athletic training program in the physical education department. All the subjects were healthy with normal body mass index and blood pressure. Their serum samples were collected before and after running for half an hour on the racing track and were analyzed for IMA colorimetrically and the data was subjected to appropriate statistical analysis.

Results:

The levels of IMA were found to be statistically significantly higher after exercise as compared to those before exercise (p = 0.005). The ratio of IMA to albumin (IMAR) was also found to be significantly higher after exercise as compared to that before exercise (p=0.000).

Conclusion:

It may be concluded that the skeletal muscle ischemia induced by moderate aerobic exercise is associated with an increased conversion of albumin to IMA.

Association between low thyroid-stimulating hormone, posterior cortical atrophy and nitro-oxidative stress in elderly patients with cognitive dysfunction

INTRODUCTION

Cortical atrophy is known to be a valuable sign of cognitive decline. The purpose of this study was to assess the association between low thyroid-stimulating hormone (TSH), posterior cortical atrophy (Koedam score - KS) and nitro-oxidative stress in elderly patients.

MATERIAL AND METHODS

A study (SG) and a control group (CG), each subdivided by gender, were investigated. Subjects older than 59 years with low serum TSH level and with mild cognitive impairment were included in the SG. The CG was formed by subjects free of significant cortical atrophy and free or thyroid dysfunction. Demographic and clinical characteristics of the patients (Mini Mental State Examination, MMSE), Koedam score on cranial magnetic resonance imaging, and blood parameters (TSH, FT4, and nitric oxide - NOx) were assessed.

RESULTS

Subjects in the study group had fewer years of education above the 8th grade compared with the control group (p < 0.0001). A significantly higher percentage of subjects in the study group had a Koedam score of 2 or 3 compared with controls, who had in the majority of cases a Koedam score of zero (p < 0.02). Significantly higher NOx levels were observed when study groups of both genders were compared with corresponding controls (p < 0.001). No significant differences were observed with regard to FT4 (p > 0.70). Nitric oxide was found to be significantly associated with TSH (p < 0.03) and KS (p < 0.002) when the whole study group was considered as well as when just the non-smoker study group was investigated.

CONCLUSIONS

Our study revealed an association between subclinical thyroid hypofunction, nitro-oxidative stress, and posterior cortical atrophy as an early stage of global atrophy.

A meta-analysis of the association of serum ischaemia-modified albumin levels with human hypothyroidism and hyperthyroidism

Serum levels of ischaemia-modified albumin (IMA) have been studied as a novel and simple measure of oxidative stress (OXS) in different thyroid pathologies. However, results of available studies in the literature were not consistent. This meta-analysis was attempted to quantify the overall effect size for serum IMA levels in human hypothyroidism (HT) and hyperthyroidism (HYT) and to study its associations with the thyroid profile. Databases of PubMed/Medline, EMBASE, Google Scholar, Web of Science and Science Direct were searched for articles. Data on serum IMA levels in HT, HYT patients and euthyroid controls were extracted to compute standardized mean differences (SMD) by the random-effects model. The associations between IMA and thyroid profile were computed by the meta-analysis of correlation coefficients. IMA levels in HT patients (SMD=1.12; Z=2.76; P=0.006) and HYT patients (SMD=1.64; Z=2.57; P=0.01) were significantly higher than in euthyroid controls and the thyroid treatment showed a favourble effect on serum IMA levels. There were strong and significant correlations between IMA and hormonal status in HT and HYT groups. This meta-analysis showing increased IMA level in both HT and HYT patients and its association with thyroid profile suggests that serum IMA could be used as a simple measure of increased OXS in thyroid dysfunction.

The effect of L-thyroxine replacement therapy on ischemia-modified albümin and malondialdehyde levels in patients with overt and subclinical hypothyroidism

BACKGROUND AND OBJECTIVES

The main objective of this study was to evaluate the levels of ischemia-modified albumin (IMA) and malondialdehyde (MDA) in patients with subclinical (SHypo) and overt hypothyroidism (OHypo), and to assess the effects of levothyroxine (LT₄) therapy on the oxidative stress (OS) parameters. We also investigated the relationships among serum thyroid hormones, lipid parameters, and IMA and MDA in these patients.

DESIGN AND METHODS

Thirty untreated patients with OHypo, 25 untreated patients with Shypo, and 30 age- and sex-matched healthy controls were prospectively included in the study. Biochemical and hormonal parameters including IMA and MDA were evaluated in all patients just before and one month after the maintenance of euthyroidism.

RESULTS

Compared with the control subjects, the levels of MDA and triglycerides (TG) significantly increased in patients with SHypo (p < 0.001 and p < 0.05, respectively), whereas high density lipoprotein cholesterol (HDL-C) levels significantly decreased (p = 0.01). Patients with OHypo showed significantly high MDA, total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), and TG levels (p = 0.001, p < 0.01, p = 0.01, and p < 0.01, respectively), and significantly low HDL-C levels compared with the controls (p < 0.05). MDA levels and lipid profile were not significantly different in the patients with OHypo when compared with the patients with SHypo. Serum IMA levels did not significantly change in patients with OHypo and SHypo compared with the controls. In the pre-treatment period, MDA levels were inversely correlated with HDL-C levels in patients with OHypo (r: -0.471, p = 0.009). Plasma MDA and LDL-C levels significantly decreased and HDL-C levels significantly increased in the groups of OHypo and SHypo after LT₄ treatment. Serum IMA levels did not significantly change with the therapy in all patient groups.

CONCLUSIONS

Increased MDA levels in both patient groups represent increased lipid peroxidation which might play an important role in the pathogenesis of the atherosclerosis seen in these patients. Increased OS in patients with SHypo and OHypo could be improved by LT₄ treatment. Also, MDA can be used as a reliable marker of OS and oxidative damage, while IMA is considered to be inappropriate.