Dityrosine suppresses the cytoprotective action of thyroid hormone T3 via inhibiting thyroid hormone receptor-mediated transcriptional activation.

Dityrosine (Dityr) is the most common oxidized form of tyrosine. In the previous studies of mice treated with dityrosine, cell death in the pancreas, kidneys, and liver was detected in the presence of enhanced plasma triiodothyronine (T3) content. Due to its structural similarity with the thyroid hormone T3, we hypothesized that dityrosine might disrupt T3-dependent endocrine signaling. The cytotoxic effect of dityrosine was studied in C57BL/6 mice by gavage with a dityrosine dose of 320 µg per kg per day for 10 weeks. Cell death in the liver was detected in the presence of enhanced plasma thyroid hormone content in mice treated with dityrosine. The antagonistic effect of dityrosine on T3 biofunction was studied using HepG2 cells. Dityrosine incubation reduced T3 transport ability and attenuated the T3-mediated cell survival via regulation of the PI3k/Akt/MAPK pathway. Furthermore, dityrosine inhibited T3 binding to thyroid hormone receptors (TRs) and suppressed the TR-mediated transcription. Dityrosine also downregulated the expressions of T3 action-related factors. Taken together, this study demonstrates that dityrosine inhibits T3-dependent cytoprotection by competitive inhibition, resulting in downstream gene suppression. Our findings offer insights into how dityrosine acts as an antagonist of T3. These findings shed new light on cellular processes underlying the energy metabolism disorder caused by dietary oxidized protein, thus contributing to a better understanding of the diet-health axis at a cellular level.

Role of miR-383 and miR-146b in different propensities to obesity in male mice.

The study was designed to investigate the possible mechanisms of hepatic microRNAs (miRs) in regulating local thyroid hormone (TH) action and ultimately different propensities to high-fat diet (HFD)-induced obesity. When obesity-prone (OP) and obesity-resistant (OR) mice were fed HFD for 7 weeks, OP mice showed apparent hepatic steatosis, with significantly higher body weight and lower hepatic TH receptor b (TRb) expression and type 1 deiodinase (DIO1) activity than OR mice. Next-generation sequencing technology revealed that 13 miRs in liver were dysregulated between the two phenotypes, of which 8 miRs were predicted to target on Dio1 or TRb When mice were fed for 17 weeks, OR mice had mild hepatic steatosis and increased Dio1 and TRb expression than OP mice, with downregulation of T3 target genes (including Srebp1c, Acc1, Scd1 and Fasn) and upregulation of Cpt1α, Atp5c1, Cox7c and Cyp7a1 A stem-loop qRT-PCR analysis confirmed that the levels of miR-383, miR-34a and miR-146b were inversely correlated with those of DIO1 or TRb. Down-regulated expression of miR-383 or miR-146b by miR-383 inhibitor (anti-miR-383) or miR-146b inhibitor (anti-miR-146b) in free fatty acid-treated primary mouse hepatocytes led to increased DIO1 and TRb expressions, respectively, and subsequently decreased cellular lipid accumulation, while miR-34a inhibitor (anti-miR-34a) transfection had on effects on TRb expression. Luciferase reporter assay illustrated that miR-146b could directly target TRb 3'untranslated region (3'UTR). These findings suggested that miR-383 and miR-146b might play critical roles in different propensities to diet-induced obesity via targeting on Dio1 and TRb, respectively.

Structure-based approach for the study of thyroid hormone receptor binding affinity and subtype selectivity.

Thyroid hormone (TH) possesses the ability to lower cholesterol and improve cardiac performance, which have prompted the efforts to design analogs that can utilize the cholesterol-lowering property without adversely affecting heart function. In order to gain insights into the interaction mechanism for agonists at the active site of thyroid hormone receptor ß (TRß), quantitative structure-activity relationship (QSAR) models have been developed on TRß agonists, significant statistical coefficients were obtained (CoMFA, R(2)cv, .732), (CoMSIA, R(2)cv, .853), indicating the internal consistency of the models, the obtained models were further validated using the test set, the acquired R(2)pred values .7054 and .7129 were in good agreement with the experimental results. The key amino acids affecting ligand binding were identified by molecular docking, and the detailed binding modes of the compounds with different activities were also determined. Furthermore, molecular dynamics (MD) simulations were conducted to assess the reliability of the derived models and the docking results. Moreover, TH exerts significant physiological effects through modulation of the two human thyroid hormone receptor subtypes. Because TRß and TRα locate in different target cells, selective TR ligands would target specific tissues regulated by one receptor without affecting the other. Thus, the 3D information was analyzed to reveal the most relevant structural features involved in selectivity. The findings serve as the basis for further investigation into selective TRß/TRα agonists.

In silico study on ß-aminoketone derivatives as thyroid hormone receptor inhibitors: a combined 3D-QSAR and molecular docking study.

In order to explore the structure-activity correlation of a series of ß-aminoketone analogs as inhibitors of thyroid hormone receptor (TR), a set of three-dimensional quantitative structure-activity relationship (3D-QSAR) models based on comparative molecular field analysis (CoMFA) and comparative molecular similarity analysis (CoMSIA), for the first time, were developed in the present work. The best CoMFA model with steric and electrostatic fields exhibited [Formula: see text], [Formula: see text] for TRß, and [Formula: see text], [Formula: see text] for TRα. 3D contour maps produced from the optimal models were further analyzed individually, which provide the areas in space where interactive fields would affect the inhibitory activity. In addition, the binding modes of inhibitors at the active site of TRs were examined using molecular docking, the results indicated that this series of inhibitors fit into the active site of TRs by forming hydrogen bonding and electrostatic interactions. The docking studies also revealed that Leu305, Val458 for TRß, and Asp407 for TRα are showing hydrogen bonds with the most active inhibitors. In any case, the 3D-QSAR models combined with the binding information will serve as a useful approach to explore the chemical space for improving the activity of TRß and TRα inhibitors.

Molecular determinants of thyroid hormone receptor selectivity in a series of phosphonic acid derivatives: 3D-QSAR analysis and molecular docking.

A mathematical study was performed on a set of phosphonic acid derivatives that are substrates for thyroid hormone receptor ß (TRß) and thyroid hormone receptor α (TRα), three-dimensional quantitative structure-activity relationship (3D-QSAR) models using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methods were employed to investigate the structural requirements for this series of compounds with improved activity. Some descriptors were also employed to significantly improve the performance of the derived models. The CoMFA model for TRß exhibited Rcv(2) of 0.612, Rpred(2) of 0.7218, whereas CoMSIA model showed Rcv(2) of 0.621, R(2)pred of 0.7358; the CoMFA model for TRα displayed Rcv(2) of 0.678, Rpred(2) of 0.6424, and the CoMSIA model had Rcv(2) of 0.671, Rpred(2) of 0.6932, which indicate that the constructed models are statistically significant. The derived contour maps further pointed out the regions where interactive fields may influence the activity. In order to validate the QSAR models and explore the origin of the selectivity at the amino acid level, molecular docking was developed, and the results indicate that Arg282, Arg320, Asn331, Gly332, Thr329 and His435 for TRß, but Ala225, Arg228, Met259, Arg262 and His381 for TRα, respectively are important residues. The information obtained from the QSAR models can be used in the design of more potent TR agonists.

Role of thyroid hormone homeostasis in obesity-prone and obesity-resistant mice fed a high-fat diet.

BACKGROUND: The exact mechanism for different propensities to obesity when consuming a high-fat diet (HFD) is largely unknown. Thyroid hormone (TH) is an important modulator of energy homeostasis and body weight. OBJECTIVE: The present study aimed to find the potential mechanisms of TH in the development of obesity-prone (OP) and obesity-resistant (OR) mice after short-term and long-term HFD feeding. METHODS: C57Bl/6 male mice were randomly divided into two groups: a low-fat diet (LFD) group and an HFD group. In the 7th week, HFD-fed mice were classified as OP or OR according to upper and lower tertiles of body weight. Half of the mice were sacrificed at this time point and the remaining mice were kept on feeding and sacrificed in the 27th week. Indirect calorimetry was performed. At harvest, serum was used for ELISA assays and oxidative stress biomarkers determination. Tissues were dissected for deiodinases activity and relative mRNA expression determination, as well as antioxidant capacity evaluation. RESULTS: In the 7th week, OP mice showed a significant body weight gain, decreased energy expenditure (EE), normal circulating TH levels, and activated HPT axis, whereas OR mice had normal body weight and maintained T(3) levels only through enhancing hepatic D1 activity. In the 27th week, OR mice gained more body weight than LFD mice accompanied by an activation of HPT axis and decreased hepatic deiodination. Genes involved in TH production were down-regulated in OP mice and up-regulated in OR mice. Changes in deiodinases activity and thyroid function were related with redox status in specific tissues. Furthermore, OP mice had more serious hepatic steatosis than OR mice, with up-regulation of T(3) target genes (e.g. Srebp1c, Acc1, Fasn) involved in lipid synthesis and down-regulation of Pgc1α, Cyp7a1 and Cpt1α. CONCLUSIONS: HPT axis function and deiodinases activity might be involved in different propensities to obesity and the ability of OR mice to resist obesity was limited.

Antioxidant and antibacterial activities of extracts from Conyza bonariensis growing in Yemen.

This study aims to examine the antioxidant and antibacterial activities and phenolic contents of Conyza bonariensis growing in Yemen. The whole plants of C. bonariensis were ultrasonically extracted by ethanol. The antioxidant activity of the extract was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ß-carotene bleaching (BCB). The effectiveness of the extract on the growth inhibition of some indicators of foodborne illness bacteria were investigated by agar well diffusion assay. The total phenols (TP), total flavonoids (TF), total tannins (TT), and total anthocyanins (TA) were determined by Folin-Ciocalteu method, aluminium chloride method, Folin and Ciocalteu method, and pH-differential method, respectively. The extract of C. bonariensis possessed TP 144.1 mg/g, TF 143 mg/g, TT 0.99mg/g, and TA 0.97mg 100g, with 94.57% inhibition of DPPH and 92.47% inhibition of BCB, and strong inhibitory effects against tested bacteria, which was approximate to those of peel extract of Punica granatum.

Association Between Thyroid Hormones, Lipids and Oxidative Stress Markers in Subclinical Hypothyroidism.

BACKGROUND: Oxidative stress plays a role in the pathogenesis of many chronic diseases. It is recognized in overt hypothyroidism while its existence in subclinical hypothyroidism (SCH) is not well established. The aim of this study was to determine whether there was increased oxidation of lipids and proteins in SCH, and examine their association with lipids and thyroid hormones. METHODS: Male adults (35-59 years) with SCH (n=467) and euthyroid controls (n=190) were studied. Anthropometric measurements, plasma lipids, thyroid stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), total antioxidant capacity (T-AOC), lipid peroxidation products, malondialdehyde (MDA), advanced oxidation protein products (AOPP) and dityrosine concentrations were measured. RESULTS: Plasma concentrations of MDA were significantly higher (p<0.05) in SCH (8.11±1.39 nmol/mL) compared with euthyroid controls (7.34±1.31 nmol/mL) while AOPP, dityrosine and T-AOC levels were not different. MDA was not associated with TSH (ß=-0.019, P=0.759), FT4 (ß=-0.062, P=0.323) and FT3 (ß=-0.018, P=0.780) in SCH while levels increased with elevated total cholesterol (ß=0.229, P=0.001), LDL (ß=0.203, P=0.009) and triglycerides (ß=0.159, P=0.036) after adjustment for age and body mass index. T-AOC reduced (ß=-0.327, P=0.030) with increased MDA in euthyroid controls and not in SCH (ß=-0.068, P=0.349), while levels increased with elevated triglycerides in both groups. CONCLUSIONS: Oxidative stress was increased in subclinical hypothyroidism as evidenced by the elevated lipid peroxidation product, malondialdehyde, while protein oxidation was absent. Thus, reduction of oxidative stress may be beneficial in patients with subclinical hypothyroidism.

Differential effects of quercetin on hippocampus-dependent learning and memory in mice fed with different diets related with oxidative stress.

High fat diets induce oxidative stress which may be involved in neurodegenerative diseases. Quercetin is a kind of antioxidant that has neuroprotective effects and potent7ial pro-oxidant effects as well. In this study, we evaluated cognitive function in mice fed with high fat diets and basic diets with or without quercetin. Male Chinese Kunming (KM) mice were randomly assigned to five groups fed with basic diet (Control), basic diet with 0.005% (w/w) quercetin (CQ1), high fat diet (HFD), HFD with 0.005% (w/w) quercetin (HFDQ1) and 0.01% (w/w) quercetin (HFDQ2) for 13weeks. At the end of the study period, fasting blood glucose (FBG), plasma and hippocampal markers of oxidative stress, plasma lipid status, Morris water maze as well as hippocampal relative mRNA expression of akt, bdnf, camkII, creb, gsk-3ß, nrf2 and pi3k were examined. The results suggested that in comparison to the control group, the escape latency was increased and percent time spent in the target quadrant was decreased, with increased reactive carbonyls, malondialdehyde (MDA) and declined expression of pi3k, akt, nrf2, creb and bdnf in the hippocampus of HFD and CQ1 groups. Conversely, higher quercetin supplemented to HFD improved antioxidant capacity and reversed cognitive decline completely. Significant correlations between the redox status and cognition-related gene expression were observed as well (P<0.05). Thus, in the case of oxidative stress, an appropriate dose of quercetin can attenuate oxidative stress to improve hippocampus dependent cognition. But under a balanced situation, quercetin exerts pro-oxidant effects to impair cognition.

Elevated plasma dityrosine in patients with hyperlipidemia compared to healthy individuals.

BACKGROUND: Dityrosine, the modification of tyrosine residues, may contribute to metabolic disorders. This study was undertaken to investigate plasma dityrosine concentrations in patients with hyperlipidemia and to examine the correlation between dityrosine and lipid profiles. METHODS: Fluorescence spectrophotometry was used to measure dityrosine in the plasma of healthy subjects (n = 203) and dyslipidemic subjects, which included patients with mild hyperlipidemia (n = 246) and hyperlipidemia (n = 179). Advanced oxidation protein products (AOPP) and malondialdehyde (MDA) were also assayed in all subjects. RESULTS: Dityrosine levels were higher by 9.3 and 22.9% in mildly hyperlipidemic and hyperlipidemic patients, respectively, compared to controls after adjustment for age, gender, and BMI. AOPP and MDA levels showed similar trends. The levels of dityrosine related positively (p < 0.05) to total cholesterol (r = 0.362), triglycerides (r = 0.449), and low-density lipoprotein cholesterol (r = 0.359). Moreover, plasma dityrosine (r = 0.408), AOPP (r = 0.488), and MDA (r = 0.181) levels were elevated with an increase in the atherosclerosis index in the subjects. CONCLUSIONS: These findings suggest that dityrosine formation may be an early event in the pathological process of hyperlipidemia. Dityrosine as a biomarker detected by fluorescence spectrophotometry might be a useful tool to evaluate the plasma redox state in hyperlipidemia.

Disparities in the Prevalence of Metabolic Syndrome (MS) and its Components Among University Employees by Age, Gender and Occupation.

BACKGROUND: Metabolic Syndrome (MS), a known risk factor for Cardiovascular Disease (CVD) and type II diabetes is an emerging epidemic in China. Studies carried out on the general population indicate a varied clustering of cardiovascular risks in many parts of the country. However, there is limited data on its prevalence in the working population. Workplace can serve as an important place for prevention, control and management of CVD risks. The aim of this study was to investigate the prevalence of MS and its components among University workers, and determine how the prevalence varied according to sex and occupation. METHODS: This was a cross-sectional study of 2,428 University employees (22-60 years) who received an annual clinical examination at the University hospital. Anthropometric measurements, blood pressure, Fasting Plasma Glucose (FPG), and lipid profiles were measured. MS was defined according to the National Cholesterol Education Program Adult Treatment panel III modified criteria. RESULTS: Overall prevalence of MS was 6.1%, higher in males (5.1%) than females (1.1%), and increased with age. The most prevalent MS components in all workers were hypertension (37.9%) and hypertryglyceridemia (20.8%), corresponding rates in males were 28.3% and 16.1% while females had a prevalence of 9.6% and 4.7%. After adjustment for age, administrative work was associated (p<0.05) with increased hypertension (odds ratio (OR) =1.474; 95% confidence interval (CI), 1.146-1.896) and hyperglycemia (OR=1.469; 95% CI, 1.082-1.993) in male workers, and with hypertension (OR=1.492; 95% CI, 1.071-2.080) in females. However, prevalence of hypertryglyceridemia was lower (OR=0.390; 95% CI, 0.204-0.746) in female administrators compared to those in academics. Obesity, MS and reduced High Density Lipoprotein (HDL) cholesterol prevalence was not different (p>0.05) between the two occupations in both sexes. CONCLUSIONS: Prevalence of MS and its components was higher in male workers than in females, increased with age, and were more common in administrative workers. The findings support the need for gender and occupation specific health interventions to prevent CVDs and type II diabetes in the workplace.

[Molecular design, structural analysis and bactericidal activity of derivatives of antimicrobial peptide buforin II].

A novel peptide, named BF2-X, was designed based on the structure-activity analysis of an analogue of Buforin II, named BF2-A. The BF2-X was a hybrid peptide containing the N-terminal residues 5 to 13 of BF2-A and three repeats of the C-terminal regular alpha-helical motif RLLR, and the residues 8 valine were replaced by leucine. The results of bioinformatics analysis had showed that compared with BF2-A, the helicity, positive charge, hydrophobicity rate and C-terminal amphipathy of BF2-X had remarkably enhanced. Both peptides showed a random coil structure in an aqueous solution, while displaying a typical alpha-helical structure in 50% trifluoroethanol solution (a membrane mimic condition). BF2-X exhibited higher alpha-helical contents than BF2-A in hydrophobic environment. BF2-X displayed potent antimicrobial activities against a broad spectrum of microorganisms. And BF2-X showed stronger antimicrobial activities against bacteria tested than parent peptide BF2-A. These results suggest that the alpha-helical content was directly correlated with the enhanced antibacterial activity. Both peptides had no hemolytic action on mouse erythrocyte.

The intracellular mechanism of action on Escherichia coli of BF2-A/C, two analogues of the antimicrobial peptide Buforin 2.

In the present study, the antimicrobial peptides BF2-A and BF2-C, two analogues of Buforin 2, were chemically synthesized and the activities were assayed. To elucidate the bactericidal mechanism of BF2-A/C and their different antimicrobial activities, the influence of peptides to E. coli cell membrane and targets of intracellular action were researched. Obviously, BF2-A and BF2-C did not induce the influx of PI into the E. coli cells, indicating nonmemebrane permeabilizing killing action. The FITC-labeled BF2-A/C could penetrate the E. coli cell membrane and BF2-C penetrated the cells more efficiently. Furthermore, BF2-A/C could bind to DNA and RNA respectively, and the affinity of BF2-C to DNA was powerful at least over 4 times than that of BF2-A. The present results implied that BF2-A and BF2-C inhibited the cellular functions by binding to DNA and RNA of cells after penetrating the cell membranes, resulting in the rapid cell death. The structure-activity relationship analysis of BF2-A/C revealed that the cell-penetrating efficiency and the affinity ability to DNA were critical factors for determining the antimicrobial potency of both peptides. The more efficient cell-penetrating and stronger affinity to DNA caused that BF2-C displayed more excellent antimicrobial activity and rapid killing kinetics than BF2-A.

Inhibition of Fe-induced colon oxidative stress by lactobacilli in mice.

Iron (Fe) can promote hydrogen peroxide (H(2)O(2)) and hydroxyl radical generation in the colonic surface and promote growth of Fe-dependent bacteria. Some Lactobacillus strains are resistant to oxygen free-radicals, allowing them to survive in a Fe-modulated mucosal environment and influence colon microbial ecology and redox state. Here, we investigated the capacity of lactobacilli with different antioxidant abilities to modify the bacterial profile and prevent oxidative stress in the colon of Fe-overloaded mice. Survival time of Lactobacillus rhamnosus LGG (LGG) in the presence of H(2)O(2) and hydroxyl radical was significantly longer compared with the mid- and non-antioxidative strains, Lactobacillus paracasei Fn032 and Lactobacillus plantarum Fn001, respectively. Different Lactobacillus strains are specific in free-radical scavenging activities of their cell-free extracts, which increased to varying extent depending on strains when bacteria were exposed to simulated gastric and pancreatic juice. Fe-overloaded mice showed increased colonic luminal ferrous Fe content, Enterococcus and Escherichia coli concentrations, mucosal malondialdehyde and free-radicals, and decreased mucosal total antioxidative capacity and oxidative enzymatic activity. Translocation of endotoxin to the liver was also significantly increased (P < 0.05). Lactobacilli inhibited ferrous Fe accumulation, especially in LGG and Fn032. LGG significantly inhibited the increase of colonic mucosal free-radicals and malondialdehyde content (P < 0.05). Fn032 only inhibited malondialdehyde (P < 0.05). LGG and Fn032 significantly inhibited increases in colonic Enterococcus (P < 0.05). Fn001 showed no significant antioxidative ability in vivo. The difference of these effects in vivo were well agreed with scavenging activities against reactive oxygen species (ROS) of simulated gastrointestinals fluid pretreated cells in vitro. In conclusion, ROS scavenging activities was essential for Lactobacillus to prevent oxidative stress in vivo and inhibition of ROS-producing bacterial growth and mucosal barrier injury.

Prevalence of headache among children and adolescents in Shanghai, China.

The aims of this study were to estimate the prevalence of headache subtypes and headache-specific disability among children and adolescents in Shanghai, China, and to assess the validity and reliability of the ID-migraine questionnaire in this population. Of 4812 students who completed the questionnaire, 466 (9.68%) had experienced a headache in the past 3 months. Of the 466 headache sufferers, 44.85% were classified as having migraine. The proportion of migraine varied with age from 23.29% to 43.48%, and high proportions were found at ages 14 years and 15 years. The average proportion of: tension-type headache was 29.18%, and the proportions of cluster and other headache were 6.22% and 19.74%, respectively. According to the Paediatric Migraine Disability Assessment Score classification, the percentage of headache sufferers with grade I disability ranged from 40.54% to 71.43% across age groups and was 61.24% overall. The overall sensitivity of the ID-migraine screening questionnaire was 39.71% and the specificity was 46.63%.

Association among retinol-binding protein 4, small dense LDL cholesterol and oxidized LDL levels in dyslipidemia subjects.

OBJECTIVES: To investigate retinol-binding protein 4 (RBP4), small dense low-density lipoprotein cholesterol (sdLDL-C) and oxidized low-density lipoprotein (ox-LDL) levels and their associations in dyslipidemia subjects. DESIGN AND METHODS: We determined RBP4, sdLDL-C, ox-LDL levels in 150 various dyslipidemia subjects and 50 controls. The correlation analysis and multiple linear regression analysis were performed. RESULTS: The RBP4, sdLDL-C and ox-LDL levels were found increased in various dyslipidemia subjects. The sdLDL-C levels were positively correlated with RBP4 (r=0.273, P=0.001) and ox-LDL (r=0.273, P=0.001). RBP4 levels were also correlated with ox-LDL (r=0.167, P=0.043). The multiple regression analysis showed that only sdLDL-C was a significant independent predictor for RBP4 (ß coefficient=0.219, P=0.009; adjusted R(2)=0.041) and ox-LDL (ß coefficient=0.253, P=0.003; adjusted R(2)=0.057) levels, respectively. CONCLUSIONS: The independent associations of sdLDL-C with RBP4 and ox-LDL were observed in dyslipidemia subjects. RBP4 may play an important role in lipid metabolism of atherosclerosis, particularly in formation of sdLDL.

Lipoic acid attenuates high-fat-diet-induced oxidative stress and B-cell-related immune depression.

OBJECTIVE: This study investigated whether spleen oxidative stress induced by a high-fat diet (HFD) influences the expression of genes involved in B-cell activation, thus leading to B-cell-related immunosuppression. METHODS: Male C57BL/6 mice were randomly assigned to one of three groups with eight mice in each group. The control group consumed an ordinary diet (4.9% fat, w/w). The other two groups were fed an HFD (21.2% fat) and an HFD plus 0.1% lipoic acid (LA). After 10 wk, plasma and spleen oxidative stress biomarkers including superoxide dismutase, catalase, glutathione peroxidase, total antioxidant capacity, reduced glutathione/oxidized glutathione ratio, and malondialdehyde were examined. The B-cell-related immune function was evaluated by examining the number of B cells, and the apoptotic percentages of splenic lymphocytes were determined by flow cytometry. Furthermore, the B-cell activation and reactive oxygen species scavenger-related genes differentially expressed between mice fed an HFD and those fed an HFD supplemented with LA were identified through complementary DNA microarray. RESULTS: The HFD induced marked decreases in the number of B cells and significantly increased the apoptotic percentages of splenic lymphocytes, accompanied by oxidative stress and increased oxidative damage, in the plasma and spleen. In addition, complementary DNA array analysis results showed that the HFD induced the decreased expression of genes associated with antioxidant defense, such as superoxide dismutase-3 (1.5-fold), metallothionein-1 (3.03-fold), glutathione peroxidase-5 (17.15-fold), and peroxiredoxin-4 (1.5), and B-cell activation, such as immunoglobulin heavy chain 6 (2.46-fold), immunoglobulin κ-chain (1.74-fold), Fc receptor (1.41-fold), and RAS-related C3 botulinum substrate-1 (7.46). The LA supplement prevented the buildup of oxidative stress and upregulated related gene expressions. CONCLUSION: These results indicate a role for LA as a possible effective supplement with an HFD to prevent the development of oxidative stress and to attenuate B-cell damnification by increasing the gene expression of the B-cell receptor signaling pathway.

The level of native and oxidized lipoprotein(a) in children with nephrotic syndrome.

OBJECTIVE: To investigate lipoprotein(a) [Lp(a)], oxidized Lp(a) [ox-Lp(a)] and Lp(a) immune complex [Lp(a)-IC] levels in children with nephrotic syndrome (NS). DESIGN AND METHODS: Plasma Lp(a), ox-Lp(a) and Lp(a)-IC levels were determined in 106 NS children in acute-period, 42 in remission and 155 controls. RESULTS: Lp(a) and ox-Lp(a) levels were significantly higher in acute-period and remission NS than in control. Ox-Lp(a) levels in acute-period NS were higher than in remission. Lp(a)-IC levels in acute-period NS were higher than in control. Lp(a), ox-Lp(a) and Lp(a)-IC were found negatively related with albumin in NS. Lp(a), ox-Lp(a) and Lp(a)-IC levels decreased after use of steroid therapy. Multiple linear regression analysis found relative change of albumin, creatinine, urea, triglyceride and high density lipoprotein cholesterol accounted for 78.9% of variation in ox-Lp(a). CONCLUSIONS: Lp(a), ox-Lp(a) and Lp(a)-IC levels were increased in NS children, which may play an important role in the processes of atherosclerosis.

Elevated plasma D-dimer and hypersensitive C-reactive protein levels may indicate aortic disorders / Níveis plasmáticos elevados do dímero D e da proteína C reativa hipersensíveis podem indicar desordens aórticas

OBJECTIVE: D-dimer and C-reactive protein are of diagnostic and predictive values in patients have thrombotic tendency, such as vascular thrombosis, coronary artery disease and aortic dissection. However, the comparative study in these biomarkers between the patients with acute aortic dissection and coronary artery disease has not been sufficiently elucidated. METHODS: Consecutive surgical patients for acute type A aortic dissection (20 patients), aortic aneurysm (nine patients) or coronary artery disease (20 patients) were selected into this study. Plasma from preoperative blood samples and supernatant of aortic homogenate of the surgical specimens were detected for D-dimer and hypersensitive C-reactive protein (hs-CRP). RESULTS: Plasma D-dimer and hs-CRP values in type A aortic dissection or aortic aneurysm were much higher than in coronary artery disease patients or the healthy control (for D-dimer, aortic dissection: coronary artery disease, 0.4344 ± 0.2958 µg/ml vs. 0.0512 ± 0.0845 µg/ml, P < 0.0001; aortic dissection: healthy control, 0.4344 ± 0.2958 µg/ml vs. 0.1250 ± 0.1295 µg/ml, P = 0.0005; aortic aneurysm: coronary artery disease, 0.4200 ± 0.4039 µg/ml vs. 0.0512 ± 0.0845 µg/ml, P = 0.0013; and aortic aneurysm: healthy control, 0.4200 ± 0.4039 µg/ml vs. 0.1250 ± 0.1295 µg/ml, P = 0.0068; and for hs-CRP, aortic dissection: coronary artery disease, 4.400± 3.004 mg/L vs. 1.232±0.601 mg/L, P < 0.0001; aortic dissection:healthy control, 4.400 ± 3.004 mg/L vs. 0.790 ± 0.423 mg/L, P < 0.0001; aortic aneurysm: coronary artery disease, 2.314 ± 1.399 mg/L vs. 1.232 ± 0.601 mg/L, P = 0.0084; aortic aneurysm: healthy control, 2.314 ± 1.399 mg/L vs. 0.790 ± 0.423 mg/L, P = 0.0002; and coronary artery disease: healthy control, 1.232 ± 0.601 mg/L vs. 0.790 ± 0.423 mg/L, P = 0.0113). Besides, there were close correlations between plasma D-dimer and hs-CRP in overall (Y = 4.8798X + 0.8138, r² = 0.4497, r = 0.671, P < 0.001), aortic dissection ...

OBJETIVO: D-dímero e proteína C reativa são de valores de diagnóstico e preditivo em pacientes com tendência trombótica, como a trombose vascular, doença arterial coronária e dissecção aórtica. No entanto, o estudo comparativo desses biomarcadores entre os pacientes com dissecção aguda da aorta e doença arterial coronariana não foi suficientemente esclarecido. MÉTODOS: Pacientes cirúrgicos consecutivos foram selecionados para este estudo por tipo de dissecção aguda aórtica (20 pacientes), aneurisma da aorta (9 pacientes) ou doença arterial coronária (20 pacientes). O plasma a partir de amostras de sangue no pré-operatório e sobrenadante de homogenato de aorta dos espécimes cirúrgicos foi detectado para o D-dímero e proteína C reativa hipersensível. RESULTADOS: Os valores do plasma de D-dímero e proteína-C reativa em dissecção aórtica tipo A ou aneurisma da aorta foram muito superiores em pacientes com doença arterial coronariana ou de controles saudáveis (pelo D-dímero, dissecção aórtica: doença arterial coronariana, 0,4344 ± 0,2958 µg/ml vs 0,0512 ± 0,0845 µg/ml, P <0,0001; dissecção aórtica: controle saudável, 0,4344 ± 0,2958 µg/ml vs 0,1250 ± 0,1295 µg/ml, P = 0,0005; aneurisma da aorta: doença arterial coronariana, 0,4200 ± 0,4039 µg/ml vs 0,0512 ± 0,0845 µg/ml, P = 0,0013; e aneurisma de aorta: controle saudável, 0,4200 ± 0,4039 µg/ml vs. 0,1250 ± 0,1295 µg/ml, P = 0,0068 e para a hs-CRP, dissecção aórtica: doença arterial coronariana, 4,400 ± 3,004 mg/L vs. 1,232 ± 0,601 mg/L, P <0,0001; dissecção aórtica: grupo controle saudável, 4,400 ± 3,004 mg/L vs 0,790 ± 0,423 mg/L, P <0,0001; aneurisma da aorta: doença arterial coronariana, 2,314 ± 1,399 mg/L vs. 1,232 ± 0,601 mg/L, P = 0,0084; aneurisma da aorta: grupo controle saudável, 2,314 ± 1,399 mg/L vs. 0,790 ± 0,423 mg/L, P = 0,0002; e doença arterial coronariana: grupo controle saudável, 1,232 ± 0,601 mg/L versus 0,790 ± 0,423 mg/L, P = 0,0113). Além disso, houve correlações próximas ...

Relation of plasma somatostatin levels with malondialdehyde in hyperlipidemic patients.

Somatostatin (SST) may protect organism from overnutrition-induced insulin resistance and oxidative stress by inhibiting pancreatic endocrine and exocrine secretion, gastrointestinal digestion and absorption. Many studies clearly show its release becomes perturbed in diabetes and obesity. Therefore, in the present study we first aimed to investigate whether or not plasma somatostatin level was different in patients with hyperlipidemia and normolipidemic controls. We also assessed the relationship between plasma somatostatin levels with atherosclerotic index (AI) and malondialdehyde (MDA) in non-diabetic dyslipidemic patients. Subjects with hyperlipidemia have insulin resistance and high levels of oxidative stress. Median somatostatin (57.2±19.2 vs 68.0±21.9 pg/mL; p<0.05) levels were lower in hyperlipidemic than in normolipidemic subjects. Significant inverse relationships between SST level and AI (r=-0.21, p< 0.05), or MDA (r=-0.31, p<0.01) were observed. These results suggest a possible protective role of endogenous SST, at least on hyperlipidemia and atherosclerosis that are attributed to excess energy intake and physical inactivity. Of course these preliminary results should be supported by prospective studies.