Effect of endurance training on retinol‐binding protein 4 gene expression and its protein level in adipose tissue and the liver in diabetic rats induced by a high‐fat diet and streptozotocin

Aims/Introduction

The present study was designed to investigate from which tissues the decrease in retinol‐binding protein 4 (RBP4) expression could contribute to the improvement of serum RBP4 and insulin resistance (IR) after endurance training.

Materials and Methods

Male 7‐week‐old Wistar rats were randomly assigned into four groups including control (C), trained (T), diabetic control (DC) and trained diabetic (TD). At 8 weeks‐of‐age, diabetes was induced by a high‐fat diet and intraperitoneal injection of low‐dose streptozotocin (STZ; 35 mg/kg). Rats in the T and TD groups carried out a 7‐week exercise program on a motorized treadmill (15–20 m/min for 20 min/day for 5 weeks), whereas the C and DC remained sedentary in their cages. Tissues gene expression and protein levels of RBP4 were assessed by using real‐time polymerase chain reaction and western blot, respectively, while serum RBP4 was measured using an enzyme‐linked immunosorbent assay kit.

Results

Exercise significantly improved IR and reduced serum concentration of RBP4 in the TD group. This reduction of serum RBP4 was accompanied by decreased RBP4 protein expression in visceral fat tissue. In contrast, exercise had no significant effect on RBP4 expression in liver and subcutaneous fat tissue in the TD group. Exercise also significantly decreased RBP4 gene expression in visceral fat tissue and muscle, whereas the effect of exercise on liver RBP4 messenger ribonucleic acid expression was not significant.

Conclusions

The present study showed that the mechanism for RBP4 reducing the effect of endurance training could involve decreased RBP4 messenger ribonucleic acid expression and its protein level in adipose tissue in STZ‐induced diabetic rats.     

Determination of toxic element levels (lead and cadmium) in commonly used cosmetic products in Iran

Toxic elements are commonly used in cosmetic products for many reasons like coloring pigments or blocking ultraviolet light; however, the level of some metals exceed specific concentration which can cause serious safety issues. This study aims to evaluate the content of lead and cadmium in samples of sunscreen and foundation creams, most frequently used brands of cosmetic products, in Iran. Concentration of lead in the sunscreens and foundation creams was lower than that of USFDA standards. The content of cadmium was higher than Europe Union standard. Effort must be made to inform the users about the harmful consequences of cosmetics.     

Oxidative stress in radiology staff

Excessive production of reactive oxygen species has been observed following acute and chronic exposure to radiation in animal models which can lead to several detrimental and irreversible outcomes in vital organs. Aim of this study was to determine the oxidative stress status in radiology unit workers which are exposed to persistent low-dose radiation. METHODS:: A group of 32 radiology unit employees along with 32 sex- and age-matched hospital workers, not exposed to low-dose radiation were recruited from two separate hospitals for the study. Exposed subjects showed higher levels of lipid peroxidation (P=0.009), total antioxidant capacity (P=0.0006) and thiol groups (P=0.03). It is concluded that occupationally exposed individuals are oxidatively stressed and precautions such as antioxidant therapy seems reasonable.     

Interplay of antibody and T cell responses in acute myocardial infarction

This study sought to investigate the interplay between antibody and T cell responses triggered by an acute myocardial infarction (MI) and their possible role in the progress of this disease. Serum samples were collected from two groups of patients, group A (n = 26) within the first week of MI, and group B (n = 28) at 2 weeks and 2 months after MI. Patients in group A were older and had higher prevalence of hypertension and previous attack of MI than patients in group B. The levels of anti-myosin immunoglobulin M and immunoglobulin G antibodies in the serum samples from group A were significantly higher than those in normal control subjects. In group B, the levels of both antibodies were lower than those in group A but remained significantly higher than those in normal control subjects at both 2 weeks and 2 months. The levels of intercellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1) in the serum samples from group A patients were significantly higher than those in normal control subjects. At 2 weeks after MI (group B), only the level of sVCAM-1, but not that of sICAM-1, was significantly higher than that in normal control subjects, and there were no significant changes in the levels of these two molecules from 2 weeks to 2 months after MI. We conclude that the higher levels of anti-myosin antibodies and adhesion molecules in group A patients as compared with group B patients may be due to higher or more frequent exposures of their immune systems to heart antigens. Furthermore, the immunoglobulin M antibody response during the first week of MI had an inverse relationship with the level of interleukin-2R (sIL-2R), which suggested a possible suppressive or regulatory role of this antibody on the cellular immune response during this time.     

Constrictive pericarditis: detection of mycobacterium tuberculosis in paraffin-embedded pericardial tissues by polymerase chain reaction

BACKGROUND: Although the utility of polymerase chain reaction (PCR) for diagnosis of acute pleuro-pericardial tuberculosis has been well established, its use for chronic constrictive pericarditis is yet to be reported. AIMS: To define the sensitivity and specificity of PCR for diagnosis of tuberculosis (TB) in patients with constrictive pericarditis. METHODS: The medical records of 30 consecutive patients with constrictive pericarditis were reviewed. In addition their historical paraffin-embedded pericardial tissues were used for new histopathologic examination and PCR amplification for Mycobacterium tuberculosis genome. RESULTS: There were 23 males and 7 females with a mean age of 35+/-19.5 years. The anticipated causes of constriction included idiopathic (n=21), tuberculosis (n=5), cardiac surgery (n=2) and post traumatic (n=2). PCR became positive in nine patients. Four out of 5 patients with tuberculous granuloma had a positive test result. In addition all 4 patients with non-tuberculous constrictive pericarditis had a negative test result. Therefore considering the presence or absence of granuloma as a diagnostic criteria, the sensitivity and specificity of PCR were 4/5 (80%) and 20/25 (80%), respectively.     

A qualitative evaluation of a breastfeeding peer counselor program.

The Breastfeeding Initiative program is a collaboration between the Michigan Department of Community Health (Women, Infants, and Children Division) and Michigan State University Extension. It aims to increase breastfeeding rates among low-income women through the use of peer counselors. The study's purpose was to identify the program's strengths, operation procedures, and improvement areas from participants' and peer counselors' perspectives. Six focus groups were conducted: 3 of peer counselors and 3 of program participants. Findings revealed that peer counselors and participants were satisfied with the quality of services due to emotional and practical assistance and breast pumps provided by peer counselors. Peer counselors' job satisfaction was explained positively by the intrinsic rewards of helping others and negatively by perceived inadequate resources and recognition. Operating procedures varied greatly. Possible improvements include expanding services, providing peer counselors with additional support, and standardizing peer counselor operating procedures. The peer counselor model can effectively support low-income breastfeeding women.     

Rescue of cardiomyocyte dysfunction by phospholamban ablation does not prevent ventricular failure in genetic hypertrophy

Cardiac hypertrophy, either compensated or decompensated, is associated with cardiomyocyte contractile dysfunction from depressed sarcoplasmic reticulum (SR) Ca(2+) cycling. Normalization of Ca(2+) cycling by ablation or inhibition of the SR inhibitor phospholamban (PLN) has prevented cardiac failure in experimental dilated cardiomyopathy and is a promising therapeutic approach for human heart failure. However, the potential benefits of restoring SR function on primary cardiac hypertrophy, a common antecedent of human heart failure, are unknown. We therefore tested the efficacy of PLN ablation to correct hypertrophy and contractile dysfunction in two well-characterized and highly relevant genetic mouse models of hypertrophy and cardiac failure, Galphaq overexpression and human familial hypertrophic cardiomyopathy mutant myosin binding protein C (MyBP-C(MUT)) expression. In both models, PLN ablation normalized the characteristically prolonged cardiomyocyte Ca(2+) transients and enhanced unloaded fractional shortening with no change in SR Ca(2+) pump content. However, there was no parallel improvement in in vivo cardiac function or hypertrophy in either model. Likewise, the activation of JNK and calcineurin associated with Galphaq overexpression was not affected. Thus, PLN ablation normalized contractility in isolated myocytes, but failed to rescue the cardiomyopathic phenotype elicited by activation of the Galphaq pathway or MyBP-C mutations.     

Expression of recombinant parvalbumin from wolf-herring fish and determination of its IgE-binding capability

In this study, we produced the recombinant form of parvalbumin from wolf-herring fish and determined its IgE reactivity. Parvalbumin cDNA was sub-cloned into pET28 and expressed in Escherichia coli BL-21. The immunoreactivities of the recombinant and native parvalbumins were compared, and the effect of calcium binding was determined by sera from 25 fish-allergic patients. ELISA and Western blotting confirmed similar IgE-reactivities of the recombinant and native proteins and confirmed that this phenomenon is highly dependent on calcium binding. The recombinant protein was 94.5% similar to carp parvalbumin (Cyp c1). Approximately 72% of patients reacted strongly with recombinant parvalbumin, 80% of them reacted with the native form and only 56% showed IgE reactivity with crude extract. Because the IgE-binding capacity of recombinant wolf-herring parvalbumin is retained and is highly similar to Cyp c1, the wild and hypoallergenic forms of this allergen could be used for diagnosis and immunotherapy of fish allergy, respectively.     

Association of KIR3DS1+HLA-B Bw4Ile80 Combination with Susceptibility to Tuberculosis in Lur Population of Iran

Background: Natural killer (NK) cells are the effector cells of innate immunity that respond to infection and tumor. Interactions between killer cell immunoglobulin like receptors (KIR) and human leukocyte antigen (HLA) class I molecules regulate NK cells responses to eliminate infected and transformed cells. Objective: To investigate the impact of KIR genes, HLA ligand genes, and KIR-HLA combinations on susceptibility to tuberculosis (TB) in Lur population of Iran. Methods: The genomic DNA of 50 patients with TB from Lorestan province of Iran was genotyped for sixteen KIR genes and their five major HLA class I ligands were determined by a polymerase chain reaction-sequence-specific primers (PCR-SSP) assay. The results were compared with those of 200 healthy unrelated Iranian individuals. Results: In Lur population of Iran, a significant decrease in frequency of KIR3DS1 was found in TB patients compared to control group (24% vs. 44.5%, OR=0.394, CI=0.194-0.798, p=0.013). Also, among the three activating genes that may use HLA class I molecules as their ligands, a significant decrease was shown in frequency of KIR3DS1 with HLA-B Bw4Ile80 ligand in TB patients compared to control group (4% vs. 23%, OR=0.14, CI=0.033-0.596, p=0.004). Conclusion: These findings imply a genetic imbalance between activating and inhibitory KIR genes and KIR-HLA combinations in Lur TB patients. Low level of activating KIR3DS1 and its combination with HLA-B Bw4Ile80 ligand might have an influence on the susceptibility to TB in Lur population of Iran.