The genetic polymorphisms and activity of glyoxalase 1 as a risk factor for acute coronary syndrome in South Indians with type 2 diabetes mellitus.

OBJECTIVE: The individuals' genetic traits predispose them to a higher or lower risk of Type 2 diabetes mellitus (T2DM) and its complications, for example, acute coronary syndrome (ACS). As carbonyl stress is responsible for the pathogenesis and complications of T2DM, and glyoxalase 1 (GLO1) is the most crucial determinant of carbonyl stress, the study aimed to explore the association between GLO1 gene polymorphism, GLO1 activity in red blood cell (RBC), plasma methylglyoxal (MG) levels, and ACS risk in South Indian T2DM patients. METHODS: A total of 150 T2DM patients with ACS as cases and 150 T2DM patients without ACS as controls were recruited in a case-control study. The rs4746, rs1049346 and rs1130534 of the GLO1 gene were analysed using TaqMan allele discrimination assay. The RBC GLO1 activity and plasma MG levels were measured. RESULTS: Significantly lower RBC GLO1 activity and higher plasma MG levels were found in cases compared to controls (p < 0.001 and p = 0.008, respectively). The genotype and allele frequencies of rs1049346 significantly differed between cases and controls (p < 0.001). For rs1130534 and rs1049346, no significant difference was found. For rs1049346, the TT and CC genotypes were associated with higher (p = 0.002) and lower (p = 0.001) ACS risk, respectively, in various genetic models. The TT genotype of rs1049346 was associated with lower RBC GLO1 activity (p = 0.004) and higher MG level (p = 0.010). In haplotype analysis, higher ACS susceptibility with the TAT haplotype (p < 0.001) and lower ACS susceptibility with the TAC haplotype (p < 0.001) were observed. Also, lower RBC GLO1 activity was associated with the TAT haplotype (p = 0.002). CONCLUSIONS: The rs1049346 of the GLO1 gene may be associated with ACS risk in South Indian T2DM patients, and the T and C allele might be essential precipitating and protective factors, respectively.

A validated and optimized method for separation and quantification of total fatty acids by gas chromatography-ion trap mass spectrometry in human plasma.

Fatty acids (FAs) are associated with many physiological functions of tissues, and their alteration has been linked with tissue-specific or systemic diseases. The current situation warrants us to have a sensitive and specific method for analysis of total FAs simultaneously from the biological fluid so that the risk prediction, diagnosis or prognosis of the disease can be made effectively. Because of greater sensitivity and resolution, a method of gas chromatography-ion trap mass spectrometry (GC-IT/MS) has been optimized and validated to quantify simultaneously 19 total FAs levels in plasma and compared with GC-triple quadrupole mass spectrometry. FAs have been transesterified by methanolic acetyl chloride to fatty acid methyl esters (FAMEs). A 65 min GC method separated all 19 FAMEs. The calibration curve had good linearity up to 313-922 µM with a correlation coefficient between 0.9882 and 0.9998. The LODs and LOQs of FAMEs were in the range of 0.63 to 9.55 and 2.12 to 31.8 µM, respectively. The method has recovery up to 144 %, stability at 4 °C for 48 h and one freeze-thaw cycle, and good intra-day and inter-day precision. The optimized method has been used to quantify plasma total FAs in type 2 diabetes mellitus patients with and without acute coronary syndrome. Though a significant difference has been found between IT/MS and triple quadrupole mass spectrometry, the GC-IT/MS can help to quantify total FAs in the clinical setting.

Assessment of Organophosphate Pesticides Exposure in Men with Idiopathic Abnormal Semen Analysis: A Cross-Sectional Pilot Study.

BACKGROUND: Because of the widespread use of organophosphate (OP) pesticides in agriculture, they are major environmental contaminants in developing countries. OP pesticides decrease sperm concentration and affect its quality, viability, and motility. studies have demonstrated the association between abnormal semen analysis and OP pesticides exposure among the high-risk population. Asthere is limited data on the percentage of OP pesticides exposure, the study aimed to determine the OP pesticides exposure in Southern Indian men with idiopathic abnormal semen analysis and find the possible source of their OP pesticides exposure. MATERIALS AND METHODS: In this cross-sectional pilot study, fifty men with idiopathic abnormal semen analysis as cases and fifty men with normal semen analysis as controls were recruited. Detailed history wastaken and general and systemic examinations were carried out. OP pesticides exposure was determined by assessment of pseudocholinesterase and acetylcholinesterase levels and urinary OP pesticides metabolites dialkyl phosphate (DAP) consisting of dimethyl phosphate (DMP), diethyl thiophosphate (DETP), and diethyl dithiophosphate (DEDTP). RESULTS: Cases had statistically significantly lower levels of pseudocholinesterase (5792.07 ± 1969.89 vs. 10267.01 ± 3258.58 IU/L) (P=0.006) and acetylcholinesterase [102.90 (45.88-262.74) vs. 570.31 (200.24-975.30) IU/L] (P=0.001) as compared to controls. Cases had a statistically significantly higher percentage of urinary DAP positivity as compared to controls (80 vs. 38%, P<0.0001). Hence, cases had a significantly higher percentage of OP pesticides exposure as compared to controls (20 vs. 4 %, P=0.015). OP-exposed cases had significantly higher urinary DETP and DEDTP levels as compared to OP non-exposed cases. Also, urinary DETP and DEDTP levels were significantly negatively associated with sperm concentration, motility, and normal morphology among OP-exposed cases. CONCLUSION: Southern Indian men with idiopathic abnormal semen analysis had a significantly higher percentage of OP pesticides exposure as compared to men with a normal semen analysis.

Carbonyl stress in diabetics with acute coronary syndrome.

The prevalence and incidence of diabetes mellitus (DM) are increasing worldwide bringing with it a significantly higher rate of complications. Various mechanisms such as carbonyl stress, polyol pathway, oxidative stress, hexosamine pathways, diacylglycerol/protein kinase-C activation, etc., are responsible for the pathogenesis of DM and its complications. Persistent hyperglycaemia and inhibition of metabolising and detoxifying enzymes lead to the excessive synthesis of carbonyl compounds such as methylglyoxal, glyoxal, and 3-deoxyglucosone, resulting in carbonyl stress. The substrates, metabolizing and detoxifying enzymes of carbonyl compounds are discussed. The mechanistic roles of carbonyl compounds and advanced glycation end products (AGEs) in atherosclerosis, insulin resistance, thrombogenicity, and endothelial dysfunction in animal and cell culture model of DM and patients with DM are summarised. Because of the essential role of carbonyl stress, therapeutics are aimed at scavenging, metabolizing, detoxifying, and inhibiting carbonyl compounds or AGEs so that their harmful effects are minimized. Clinically used drugs, plants extracts and miscellaneous chemical with antiglycation properties are used in an animal model of DM to alleviates the impact of carbonyl compounds. Extensive clinical trials with derivatisation of available antiglycation agents to increase the bioavailability and decrease side effects are warranted further.

Clinical utility of validated gas chromatography-ion trap mass spectrometry in patients with anticholinesterase pesticides poisoning.

Intentional or unintentional intake of anticholinesterase pesticides became common due to their extensive use in agricultural and domestic purposes, resulting in numerous poisoning cases. A simple, accurate, and sensitive gas chromatography-ion trap mass spectrometry-based method for the quantification of 12 anticholinesterase pesticides (monocrotophos, dimethoate, dichlorvos, azinphos-methyl, carbofuran, chlorpyrifos, dialifos, diazinon, malathion, parathion, methidathion, and terbufos) in serum was developed, and its utility in patients with alleged pesticides poisoning was assessed. The quantification was performed using liquid-liquid extraction by toluene/chloroform (4:1,v/v) with 500 µL of serum. On column limit of detection and limit of quantification were less than 50.00 µg/L. The recovery ranged from 97.54 to 103.23%. The calibration curves were linear (R2 > 0.9937). Accuracy was found to be between - 7.1 and 7.2%. Intra-day and inter-day reproducibility was less than 17% for the spiked quality control serum samples. The level of pesticide in serum quantified by the validated method correlated with clinical signs and symptoms, pseudo-cholinesterase activity, total atropine dose, length of hospital stay, and clinical outcome in 15 patients with alleged pesticide poisoning. The validated method may be used for monitoring and prognosis in patients with pesticide poisoning and diagnosis of poisoning in forensic toxicology.

Phytosteroid 28-homobrassinolide targets cholesterol and glucose homeostasis implicating ABCA1 and SREBP role in regulation.

Oxysterols are natural ligands of certain nuclear receptors known as liver X receptors (LXR). LXRs are regulators of fatty acid, cholesterol, and glucose homeostasis. Dietary phyto-oxysterol 28-homobrassinolide (28-HB) has been demonstrated to transactivate rat LXR α and ß. In this study we assessed the potential of 28-HB to effect such changes in - (1) human HepG2 cancer cell line, (2) isolated perfused goat liver, and (3) high-fat diet-fed C57BL/6J mice. Serum and perfusate marker levels along with hexokinase activity were determined through enzyme assays. Fat deposition was studied by Oil Red O staining, ATP-binding cassette transporter (ABCA1), and sterol regulatory element-binding transcription factor 2 (SREBP2) protein expression by Western blot and their mRNA expression through real-time PCR. In HepG2 cells, 28-HB (5-20 µM) treatment indicated a 2-fold increase in glucose utilization and ABCA1 and SREBP2 protein expression within 12 h. Tissue glucose and cholesterol levels decreased in 28-HB perfused goat liver within 2 h, whereas cholesterol level increased 54% in the perfusate (p < 0.05) and tissue hexokinase activity increased 23% (p < 0.05). Glucokinase, ABCA1, and SREBF1 gene expression increased 2.6, 5.37, and 2.85 fold respectively in the perfused tissue after 4 h. High-fat diet-fed C57BL/6J mice when treated with 28-HB (1-20 µg/day) for 6 weeks exhibited a marked decrease in aortic fat deposit and serum marker levels. Our study suggests that 28-HB modulates cholesterol and glucose homeostasis in animal cells through activation of LXR involving ABCA1 and SREBP-1 and 2 augmentations.

Association between carbonyl stress markers and the risk of acute coronary syndrome in patients with type 2 diabetes mellitus-A pilot study.

BACKGROUND AND AIMS: Carbonyl stress is one of the mechanisms responsible for diabetes and its complications. The study was planned to examine the relationship between carbonyl stress markers and the risk of acute coronary syndrome (ACS) in patients with type 2 diabetes mellitus (T2DM). METHODS: Forty T2DM patients with ACS and forty T2DM patients without ACS participated in this cross-sectional pilot study. Routine biochemical investigations, creatine kinase-total (CK-T), and creatine kinase-MB (CK-MB) levels were estimated. Serum carbonyl stress markers were analysed by enzyme-linked immunosorbent assay. Binary logistics regression was done to determine the predictive value of carbonyl stress markers for ACS. RESULTS: Fasting plasma glucose, serum total methylglyoxal (MG), methylglyoxal derived hydroimidazolones-1 (MG-H1), and Nε-carboxymethyl-lysine (CML) levels were significantly higher in T2DM patients with ACS than in those without ACS. Serum glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and glyoxalase-1 (GLO1) levels were significantly lower in T2DM patients with ACS than in those without ACS. Fasting plasma glucose level was significantly positively correlated with serum MG (r = 0.441, P < 0.001), CML (r = 0.649, P < 0.001), MG-H1 (r = 0.725, P < 0.001), and negatively correlated with serum GAPDH (r = - 0.268, P = 0.012) and GLO1 (r = - 0.634, P = 0.016). Receiver operating characteristic curve analysis showed that serum GAPDH and GLO1 could predict the risk of ACS in T2DM patients. CONCLUSION: These findings revealed that high carbonyl stress due to lower levels of GAPDH and GLO1 may predispose patients with T2DM for more risk of ACS.