Organochlorine pesticides induce epithelial as well as inflammatory mediators following exposure to human ovarian surface epithelial cells: An in vitro study.

Although studies have suggested organochlorine pesticides (OCPs) exposure increased the risk of epithelial ovarian cancer, the mechanisms underlying its potential tumorigenic effects in the human ovary are not well understood. In this study, we investigated the impact of dichlorodiphenyldichloroethylene (DDE), endosulfan, and heptachlor exposure on epithelial cadherin (E-cadherin) and proinflammatory mediators in human ovary surface epithelial (HOSE) cells. We found that DDE, endosulfan, and heptachlor exposure resulted in epithelial differentiation accompanied by upregulation of E-cadherin expression and overexpression of proinflammatory cytokines (TNFα, IL-1ß, and IL-6) in HOSE cells. The epithelial differentiation may accelerate HOSE cells to inclusion body formation, a common site for ovarian cancer initiation and persistent exposure to OCPs creates a chronic inflammatory microenvironment that may promote the neoplastic transformation of HOSE cells within the inclusion cyst.

Chromium Exposure in Late Gestation Period Caused Increased Levels of Cr in Brain Tissue: Association with Alteration of Activity and Gene Expression of Antioxidant Enzymes of F1 and F2 Generation Mice.

Chromium is a micronutrient which has found frequent use as supplements during pregnancy and could have a role in altering the antioxidant status in the brain. The present study was undertaken to estimate chromium levels in the brain, antioxidant enzyme activity with their gene expression, and learning and memory parameters on F1 and F2 generation mice when the F0 was exposed to chromium. The chromium levels in the brain were estimated using atomic absorption spectrophotometer. The enzyme activity of glutathione-s-transferase (GST) and catalase (CAT) was estimated and their gene expression was evaluated using RT-PCR. The spatial memory was tested using Morris water maze. The learning and recall memory was tested using the step down latency paradigm. The chromium levels were significantly raised in animals treated with Cr per se in F1 generation and quercetin cotreatment reduced the Cr levels in brain significantly. The enzyme activity of GST was significantly less in Cr-treated animals of both generations and this effect was significantly reversed on cotreatment with quercetin. The gene expression of GST matched the enzyme activity. However, catalase activity did not show significant decrease with Cr but cotreatment with quercetin resulted in significant decrease compared with control and this effect was not matched by its gene expression. We observed no significant change in learning and memory parameters in both generations following Cr exposure. Thus, this study demonstrates that chromium exposure in gestation causes changes in enzyme activity especially GST and this change was matched by change in gene expression in GST but not CAT. There was no effect on memory at the given dose.

Expression Analysis of MicroRNA-21 and MicroRNA-122 in Hepatocellular Carcinoma.

BACKGROUND/OBJECTIVE: Hepatocellular carcinoma (HCC) is a multistep process starting from chronic hepatitis (CH) that progress through cirrhosis to HCC. The expression level of microRNA (miRNA) was found to be deregulated in HCC. The study was designed to find out whether the expression level of miR-21 and miR-122 was deregulated in HCC compared to controls without HCC. METHODS: Real-time quantitative polymerase chain reaction was performed to find out the miRNA expression level using Ct value followed by statistical analysis where P value ≤ 0.05 was considered as significant. RESULTS: Overexpression of miR-21 and miR-122 in HCC was detected. All changes in the expression level of miR-21 and miR-122 were due to HCC compared with healthy control, CH, and liver cirrhosis. Hence miR-21 and miR-122 are suitable to differentiate HCC with an efficient diagnostic power of sensitivity, specificity, and expression level, but they might not have any role in patients' survival. CONCLUSION: miR-21 and miR-122 could be considered as potential markers of HCC screening molecule in addition to other approved markers. However the current study is limited to expression levels of miRNAs from serum; therefore, it needs further validated study in a large group of population to fulfill all the criteria of a biomarker.

Cadmium level in brain correlates with memory impairment in F1 and F2 generation mice: improvement with quercetin.

The increased exposure to cadmium (Cd) through environmental pollutants, food and cigarette smoke is a concern worldwide. The association of Cd with impaired learning disabilities led us to hypothesise that cadmium levels in brain tissue could be dose-dependently related to the extent of memory impairment and oxidative stress. In this study, we proposed to study whether cadmium exposure to dams could alter the brain Cd levels, memory parameters, antioxidant enzymes in brain and their gene expression in the F1-F2 generation mice and whether quercetin could modulate this effect. Animals were administered Cd alone and in combination with quercetin for 7 days during their gestation period. Their newborn pups (F1 and F2 mice) were reared until adulthood and were tested for memory using Morris water maze and step-down latency test. The brain tissue of F1 mice was collected. Cd levels were estimated using the atomic absorption spectrophotometer. G-S-transferase (GST) and catalase (CAT) activity were measured and fold increase in their respective gene expression was observed using the RT-PCR method. Cd levels were significantly increased in the brain tissue of animals exposed to Cd but cotreatment with quercetin showed decreased levels in both generations. Memory impairment was observed in animals of F1 generation exposed to Cd and cotreatment with quercetin (100 mg/kg) reversed this effect. Cd exposure significantly enhanced both activity and expression of GST and CAT in the brain tissue of F1 generation mice and quercetin attenuated this effect. In F2 generation, results were variable. GST activity and expression increased with Cd and decreased with quercetin cotreatment. However, CAT activity showed no significant change despite a decrease in gene expression. Quercetin cotreatment enhanced activity as well gene expression in F2 generation. Our study insinuates that Cd levels could act as a predictor of memory impairment and altered enzyme activity and gene expression in brain tissue. Quercetin helped to reduce Cd levels in brain tissue of F1 and F2 generation and modulated the antioxidant system of the cell by affecting expression of antioxidant enzymes at the transcription level.

Serum and Urinary Hepcidin for Diagnosing Iron-deficiency Anemia in Under-5 Children.

Bone marrow iron estimation remains the gold standard for diagnosing iron-deficiency anemia (IDA); serum ferritin, total iron-binding capacity, and transferrin saturation are routinely used as surrogate markers of IDA. However, these tests are marred by problems like poor specificity and sensitivity. Recently, hepcidin, a protein hormone synthesized in the liver and excreted in urine, has been shown to be related to iron status. We estimated the serum and urinary hepcidin levels in healthy children 6 to 60 months of age with (n=30) and without IDA (n=30). The mean (SD) serum hepcidin levels in children with IDA were significantly lower than those in children without IDA (3.03 [1.06] vs. 4.78 [3.94] ng/mL; P=0.02). The mean (SD) urinary hepcidin levels were also significantly lower in children with IDA than those in children without IDA (2.29 [0.53] vs. 2.79 [0.75] ng/mL; P=0.004). Performance of urinary and serum hepcidin compared with serum ferritin (<12 µg/L) for diagnosing IDA in terms of area under the receiver operating characteristic curve was 0.704 (P=0.007) and 0.59 (P=0.22), respectively. Serum hepcidin is not useful for diagnosing IDA in under-5 children. In contrast, urinary hepcidin holds promise as a noninvasive diagnostic tool for IDA in under-5 children.

Alteration in cognitive behaviour, brain antioxidant enzyme activity and their gene expression in F1 generation mice, following Cd exposure during the late gestation period: modulation by quercetin.

We investigated whether in-utero Cd(II) chloride exposure of the dams between 14th to 21st day of gestation affects memory and learning, oxidative stress, antioxidant enzyme activity and their gene expression in brain of the pups in their adulthood. In the Morris water maze, cadmium (Cd) exposure impaired spatial memory which was reversed following co-treatment with quercetin (100 mg/kg). In the passive avoidance paradigm, retention memory was adversely affected but was significantly reversed by co treatment with quercetin (25, 50, 100 mg/kg). The malondialdehyde and catalase (CAT) levels and glutathione-S-transferase (GST) activity were increased significantly in Cd-treated group, but were reversed by quercetin (all doses). The gene expression for CAT and GST in brain tissue of Cd treated animals also increased many folds as compared to the control, and this effect was decreased on co-treatment with quercetin (all doses), thus matching with the respective enzyme activities. Quercetin (25 mg/kg) when co-treated with Cd caused a decrease in GST activity compared to control, which points towards a complex interplay with oxidative free radicals and promoters and transcription factors. Thus, Cd exposure during late gestation causes impaired spatial and retention memory in the next generation which may be due to alteration of activity as well as gene expression of the antioxidant enzymes, CAT and GST. Quercetin may offer some protection of memory impairment probably by modulating these effects.

Delineating Potential Transcriptomic Association with Organochlorine Pesticides in the Etiology of Epithelial Ovarian Cancer.

BACKGROUND: Recent studies have shown that there is an increased risk of Epithelial Ovarian Cancer (EOC) with Organochlorine Pesticides (OCPs). However, the alteration in the gene expression profile has not been explored so far. The goal of the present study is to understand the probable molecular mechanism of OCPs toxicity towards discovery of dysregulation of signaling pathway associated with differential gene expression and candidate transcriptomic set of markers in the pathophysiology of EOC in OCPs exposed population. METHODS: The OCP levels were estimated by gas chromatography and whole genome differential expression study was carried out using expression microarray and candidate genes were validated using Real time RT-PCR. RESULTS: Significant level of OCP residues such as ß-hexachlorocyclohexane (ß-HCH), Heptachlor, Heptachlor epoxide B (HTEB), dichlorodiphenyldichloroethylene (p'p'-DDE) and endosulfan-I was found between healthy and EOC patients. The transcriptome profile of several genes revealed regulation of various important cellular processes such as metabolism, inflammation, cytoskeleton dysregulation of TGF and WNT pathway in EOC cases with high OCPs. CONCLUSION: This study provides the first evidence showing that differentially expressed genes and dysregulation of signaling pathways might be associated with significant level of OCPs exposure in ovary tissue of epithelial ovarian cancer patients. Moreover, significant correlation of these genes with OCPs revealed that OCPs exposure played vital role in dysregulation of related pathways in the etiology of EOC.

Lead-induced DNA damage and cell apoptosis in human renal proximal tubular epithelial cell: Attenuation via N-acetyl cysteine and tannic acid.

This study investigates the exposure of lead-induced reactive oxygen species (ROS) generation, DNA damage, and apoptosis and also evaluates the therapeutic intervention using antioxidants in human renal proximal tubular cells (HK-2 cells). Following treatment of HK-2 cells with an increasing concentration of lead nitrate (0-50 µM) for 24 h, the intracellular ROS level increased whereas the GSH level decreased significantly in a dose-dependent manner. Comet assay results revealed that lead nitrate showed the ability to increase the levels of DNA strand breaks in HK-2 cells. Lead exposure also induced apoptosis through caspase-3 activation at 30 µg/mL. Pretreatment with N-acetylcysteine (NAC) and tannic acid showed a significant ameliorating effect on lead-induced ROS, DNA damage, and apoptosis. In conclusion, lead induces ROS, which may exacerbate the DNA damage and apoptosis via caspase-3 activation. Additionally, supplementation of antioxidants such as NAC and tannic acid may be used as salvage therapy for lead-induced DNA damage and apoptosis in an exposed person.

Cadmium exposure during lactation causes learning and memory-impairment in F1 generation mice: amelioration by quercetin.

Cadmium (Cd) is a known pollutant present in the environment at low levels and is reported to affect reproduction in many ways. The present study was undertaken to explore the effect of Cd in F1 generation mice on cognitive parameters, and to further investigate whether quercetin could modulate these effects. In this study, female lactating mice were exposed to cadmium for seven days just after delivery. The new born pups in their adulthood were tested for learning and memory parameters by passive avoidance task and Morris water maze (MWM) test. It was observed that pups exposed to Cd showed significant impairment of memory in step down latency test, which was reversed by quercetin (100 mg/kg). In MWM test for spatial memory, animals exposed to Cd exhibited increased escape latency, which was reversed by quercetin (50 mg/kg) significantly. Quercetin alone (50 and 100 mg/kg) also demonstrated improved spatial memory, and showed improved retention memory in the passive avoidance paradigm at dose 50 mg/kg. On testing oxidative stress parameters, we observed significantly increased malondialdehyde (MDA) levels in brain tissue of Cd-treated mice. Moreover, co-treatment with quercetin (50 mg/kg) and Cd significantly reduced these MDA levels. The other doses (25 and 100 mg/kg) also showed reduction in MDA levels as compared to the group exposed to Cd alone, though the difference was not statistically significant. Hence, this study highlights the possibility of cognitive impairment in adulthood if there is Cd exposure during lactation and oxidative stress could possibly attribute to this effect.

Quercetin Modulates the Effects of Chromium Exposure on Learning, Memory and Antioxidant Enzyme Activity in F1 Generation Mice.

In the present study, we investigated whether chromium (Cr) administered to the dams (F0) during lactation period could affect memory and oxidative stress in F1 generation mice in their adulthood and whether quercetin could modulate these effects. Morris water maze (MWM) was used to test for spatial memory. Passive avoidance task and elevated plus maze were used to test for acquisition and retention memory. Oxidative stress was evaluated by measuring glutathione-S-transferase (GST), catalase activity and malonaldehyde (MDA) levels in the brain tissue. The results of MWM showed that the animals in the Cr-treated group compared to control have better spatial memory that was further enhanced when Cr was administered along with quercetin (50 mg/kg). The elevated plus maze test also showed the Cr-treated group to improve acquisition as well as retention memory compared to control. Co-treatment with quercetin (all doses) also exhibited enhanced acquisition and retention memory compared to control. The passive avoidance task demonstrated no significant improvement in memory in the Cr-treated mice but co-treatment with quercetin (100 mg/kg) showed improved acquisition memory compared to control which was significantly better than the animals treated with chromium alone. GST activity was significantly increased in the Cr-treated animals, and this was further increased in groups treated with Cr and quercetin (all doses). Chromium when administered alone and in combination with quercetin (all doses) significantly reduced MDA levels. However, Cr treatment did not show significant change in catalase activity. Nevertheless, co-treatment with quercetin (25 and 50 mg/kg) resulted in significant decrease in catalase activity. Thus, our study demonstrates that Cr exposure during lactation could be beneficial for pups with respect to augmentation of cognitive function and reduction of oxidative stress. Quercetin could probably enhance this effect to some extent.

Effect of Low-Intensity Microwave Radiation on Monoamine Neurotransmitters and Their Key Regulating Enzymes in Rat Brain.

The increasing use of wireless communication devices has raised major concerns towards deleterious effects of microwave radiation on human health. The aim of the study was to demonstrate the effect of low-intensity microwave radiation on levels of monoamine neurotransmitters and gene expression of their key regulating enzymes in brain of Fischer rats. Animals were exposed to 900 MHz and 1800 MHz microwave radiation for 30 days (2 h/day, 5 days/week) with respective specific absorption rates as 5.953 × 10(-4) and 5.835 × 10(-4) W/kg. The levels of monoamine neurotransmitters viz. dopamine (DA), norepinephrine (NE), epinephrine (E) and serotonin (5-HT) were detected using LC-MS/MS in hippocampus of all experimental animals. In addition, mRNA expression of key regulating enzymes for these neurotransmitters viz. tyrosine hydroxylase (TH) (for DA, NE and E) and tryptophan hydroxylase (TPH1 and TPH2) (for serotonin) was also estimated. Results showed significant reduction in levels of DA, NE, E and 5-HT in hippocampus of microwave-exposed animals in comparison with sham-exposed (control) animals. In addition, significant downregulation in mRNA expression of TH, TPH1 and TPH2 was also observed in microwave-exposed animals (p < 0.05). In conclusion, the results indicate that low-intensity microwave radiation may cause learning and memory disturbances by altering levels of brain monoamine neurotransmitters at mRNA and protein levels.

Increased level of organochlorine pesticides in chronic kidney disease patients of unknown etiology: role of GSTM1/GSTT1 polymorphism.

Chronic kidney disease (CKD) of unknown etiology represents about 16% of CKD patients in Indian subcontinents and 10% worldwide. The aetiology of CKD of unknown etiology remains unclear though epidemiological studies indicate the involvement of the environmental toxins. Organochlorine pesticides (OCPs) have been detected in general population in India. It is possible that polymorphism of xenobiotic metabolizing enzymes (XMEs) may play an important role in this process. In this we intend to find out blood levels of OCPs in CKD patients of unknown etiology and to evaluate the consequence of glutathione S-transferase (GST) gene polymorphism on the same. We have assessed 270 CKD patients and 270 age-sex-matched healthy controls for this study. The blood OCP levels were analyzed by gas chromatograph. GSTM1, GSTT1 genotyping were carried out by multiplex PCR. Blood levels of HCH, endosulfan and total pesticides were significantly higher in CKD patients and negatively correlated with eGFR. The combined frequency of GSTM1(-)/GSTT1(-) genotype increased the risk of CKD by 1.8-fold as compared to healthy controls. To find out the dependence of blood OCPs level on genotype, we carried out logistic regression analysis and results revealed that GSTM1(-)/GSTT1(-) genotype associated significantly with a number of OCPs namely γ-HCH, p,p'-DDT and total pesticides. Polymorphism of XMEs not only increased accumulation of pesticides but also aggravates kidney dysfunction as evident from significant decrease in eGFR.

Evaluation of therapeutic efficacy of Majoon Suranjan, a Unani formulation, in the treatment of rheumatoid arthritis: an experimental study.

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disorder. Allopathic treatments for RA have various side-effects and limitations. Majoon Suranjan (MS) is a polyherbal Unani formulation used to treat RA. Although it is widely used, evidence-based toxicity and efficacy data are not available. The present study was designed to assess the safety and therapeutic efficacy of MS in experimental animals. Acute (14 days) and long-term (90 days) toxicity studies were carried out at three doses of MS, i.e. 440, 880 and 1760 mg/kg body weight in male and female Wistar rats. Arthritis was induced in male rats by immunization with bovine collagen type II and they were treated with vehicle, methotrexate (0.25 mg/kg body weight, intraperitoneal once weekly) and MS (880 mg/kg body weight, orally, daily) for 20 days. Serum rheumatoid factor, anticyclic citrullinated peptide antibody, antinuclear antibody and C-reactive protein (CRP) were estimated. None of the rats exhibited overt toxicity or mortality and MS was found to be safe at the tested doses. No abnormal findings were observed in haematological and biochemical parameters, necropsy and histopathology at therapeutic effective dose. MS significantly inhibited the footpad swelling in arthritic rats while serum autoantibodies and CRP levels were significantly decreased. The present study demonstrates that at therapeutic doses, the Unani medicine, MS is relatively safe. Furthermore, MS was found to be effective in decreasing the biomarkers of RA, thus providing scientific evidence in support of its traditional use in the treatment of RA.

Association of CYP1A1 gene polymorphism with chronic kidney disease: a case control study.

CYP1A1 is an important xenobiotic metabolizing enzyme, present in liver and kidney. Expression of CYP1A1 enzyme increases manifold when kidney cells are exposed to nephrotoxins/chemicals leading to oxidative stress-induced cell damage. To study the association of CYP1A1 gene polymorphism in patients of chronic kidney disease with unknown etiology (CKDU), we recruited 334 CKDU patients and 334 age and sex matched healthy controls. CYP1A1*2A and *2C polymorphisms were studied by PCR-RFLP and allele specific-PCR respectively. Subjects carrying at least one mutant allele of CYP1A1*2A (TC, CC) and *2C (AG, GG) were shown to be associated with 1.4-2-fold increased risk of CKDU. Also, genotypic combinations of hetero-/homozygous mutants of CYP1A1*2A (TC, CC) with hetero-/homozygous mutant genotypes of CYP1A1*2C (AG, GG) i.e. TC/AG (p<0.01), TC/GG (p<0.05), CC/AG (p<0.05) and CC/GG (p<0.01) were associated with CKDU with an odd ratio ranging 1.8-3.3 times approximately. This study demonstrates association of CYP1A1 polymorphisms with CKDU.

A randomized, prospective study of efficacy and safety of oral tramadol in the management of post-herpetic neuralgia in patients from north India.

OBJECTIVE: To evaluate the safety and efficacy of oral tramadol therapy (50 to 200 mg/day) in the treatment for post-herpetic neuralgia (PHN). METHODS: The study was a prospective, single-blind, non-responder vs. responder, randomized trial conducted in 100 outpatients of PHN after oral administration of tramadol for 4 weeks. Those patients who had achieved 50% or greater pain relief after 14 days of oral tramadol treatment were categorized as responders and those reporting < 50% pain relief were categorized as non-responders. Rescue analgesia was provided by the topical application of a cream consisting of the combination of 3.33% doxepin and 0.05% capsaicin to the affected areas of PHN patients of both groups for at least 14 days, along with tramadol therapy. The rescue analgesia was extended to 4 weeks in patients of the non-responder group. The primary endpoints were measured using a numerical rating scale (NRS) at rest and with movement. Secondary endpoints included additional pain ratings such as global perceived effect (GPE), Neuropathic Pain Symptom Inventory scores (NPSI), daily sleep interference score (DSIS), quality of life (QOL) as per WHO QOL-BREF Questionnaire scores, patient and clinician ratings of global improvement. The 2 groups were compared on the basis of pain intensity scores, encompassing primary as well as secondary endpoints, and QOL after 28 days of the treatment regimen. RESULTS: Pain intensity scores measured by NRS (at resting and with movement), NPSI, and DSIS were consistently reduced (P < 0.001) over 28 days at varying intervals in both the groups, but the magnitude of reduction was higher in responders than non-responders. A concomitant improvement (P < 0.001) was observed in GPE on days 3, 14, and 28 as compared to the respective baseline scores in both the groups. Although the WHO QOL-BREF scores showed significant (P < 0.001) improvement in QOL of PHN patients at days 14 and 28 in both the groups, the magnitude of improvement was higher in responders as compared to non-responders. Significant improvement in pain intensity scores and QOL in non-responders is mainly attributed to the use of rescue analgesia for 28 days rather than recommended tramadol therapy. CONCLUSIONS: Treatment with tramadol 50 to 200 mg per day was associated with significant pain reduction in terms of enhanced pain relief, reduced sleep interference, greater global improvement, diminished side-effect profile, and improved QOL in PHN patients from North India. Further categorization of PHN patients may be helpful so that additional or alternative therapy may be prescribed to non-responders.

Quinalphos induced oxidative stress and histoarcheitectural alterations in adult male albino rats.

Quinalphos is a synthetic organophosphate used as a broad spectrum insecticide and acaricide. The present study investigates the effect of three sub-lethal doses (0.52, 1.04, 2.6 mg/kg b.wt) of quinalphos for variable durations (15, 30 and 90 days) on oxidative stress and histopathological changes in adult male rats. Quinalphos treatment for 15 and 30 days resulted in a dose dependent significant increase in malondialdehyde (MDA) levels and glutathione-S-transferase (GST) activity together with a concurrent decrease in ferric reducing ability of plasma (FRAP) and glutathione (GSH) content. Quinalphos treatment for 90 days also induced a significant increase in MDA levels and GST activity but the effect was not dose-dependent. Histopathological examination of liver revealed architectural disarray and dilatation of sinusoids, focal fatty changes, accumulation of eosinophils and single cell necrosis with increasing doses. However, spleen and kidney did not show any histological changes. Administration of quinalphos resulted in oxidative stress and free radical induced injury as evidenced by increased lipid peroxidation, decreased FRAP and histopathological changes in liver.

Study on organochlorine pesticide levels in chronic kidney disease patients: association with estimated glomerular filtration rate and oxidative stress.

Nephrotoxicity of organochlorine pesticides (OCPs) has been established in experimental animal models. This study was designed to evaluate the relationship of the blood OCPs level with the estimated glomerular filtration rate (eGFR) and oxidative stress (OS) in chronic kidney disease (CKD) patients. Patients in different stages of CKD (n = 150) and age, sex matched healthy controls (n = 96) were recruited. The blood OCPs level were analyzed by gas chromatography, and plasma levels of several OS parameters such as malondialdehyde (MDA), protein carbonyl, advanced oxidation protein products (AOPP), and total thiols were quantified by standard spectrophotometric methods. We observed significantly higher levels of hexachlorocyclohexane (α, γ), endosulfan, aldrin, p,p'-dichlorodiphenyldichloroethylene (DDE), and total pesticides in CKD patients. Negative correlation was also observed for aldrin, p,p'-DDE and total pesticides (p < 0.05) with eGFR. Plasma levels of MDA and AOPP showed significant positive association with the total pesticides level, indicating augmentation of OS with increased accumulation of OCPs in CKD patients.

Alterations in T-lymphocyte sub-set profiles and cytokine secretion by PBMC of systemic lupus erythematosus patients upon in vitro exposure to organochlorine pesticides.

Chronic exposure to organochlorine pesticides (OCP) has been suspected of causing immunoregulatory abnormalities that eventually lead to development and progression of systemic lupus erythematosus (SLE), but the role of these non-genetic stimuli has remained poorly understood. The objectives of the study were to quantify the levels of different OCP residues in the blood of SLE patients and to study the effects of in vitro treatment of peripheral blood mononuclear cells (PBMC) from these patients and healthy controls with OCP. Levels of different OCP residues in the blood were measured by gas-liquid chromatography. Isolated PBMC were treated in vitro with hexachlorocyclohexane (HCH), o,p'-dichlorodiphenyltrichloroethane (DDT), or phytohemagglutinin-M (PHA-M) for 72 h, then stained with different dye-labeled monoclonal antibodies to analyze alterations in T-lymphocytes using flow cytometry. Levels of different T(H)1 and T(H)2 cytokines were also estimated by ELISA. Significantly higher levels of p,p'-DDE and ß-HCH were detected in the blood of SLE patients than in healthy controls. HCH exposure markedly increased the percentages of CD3(+)CD4(+) T-lymphocytes and expression of CD45RO(+) on CD4(+) and CD8(+) T-lymphocytes, but decreased CD4(+)CD25(+) T-lymphocytes in SLE patients. DDT exposure increased the percentages of CD3(+)CD4(+) T-lymphocytes and decreased those of CD4(+)CD25(+) T-lymphocytes in SLE patients as compared to healthy controls. No significant responsiveness of patient PBMC to PHA-M stimulation was observed indicating suppression of T-lymphocytes by these OCP. Further, both HCH and DDT decreased the levels of IL-2 and IFNγ but had no effect on IL-4 levels in SLE patients. DDT also increased significantly the levels of IL-10 in patients. It is likely that higher levels and prolonged durations of exposure to HCH and DDT may significantly influence T-lymphocyte sub-sets and cytokine expression in vivo that could lead to the development or exacerbation of SLE.

Advanced glycation end products enhance reactive oxygen and nitrogen species generation in neutrophils in vitro.

Increased oxidative stress (OS) in diabetes mellitus is one of the major factors leading to diabetic pathology. However, the mediators and mechanism that provoke OS in diabetes is not fully understood, and it is possible that accumulation of advanced glycation end products (AGEs) formed secondary to hyperglycemic conditions may incite circulating polymorphonuclear neutrophils (PMN) to generate reactive oxygen species (ROS). In this report, we aim to investigate the effect of AGE on reactive oxygen and nitrogen species generation and subsequent OS in PMN. AGE-HSA exert dose- and time-dependent enhancement of ROS and reactive nitrogen intermediates (RNI) generation by PMN. Increased ROS and RNI generation were found to be mediated through the upregulation of NADPH oxidase and inducible nitric oxide synthase (iNOS), respectively, as evident from the fact that AGE-treated neutrophils failed to generate ROS and RNI in presence of diphenyleneiodonium, a flavoprotein inhibitor for both enzymes. Further increased generation of ROS and RNI ceased when the cells were incubated with anti-RAGE antibody suggesting the involvement of AGE-RAGE interaction. Also increased malondialdehyde (MDA) and protein carbonyl formation in AGE-exposed PMN suggest induction of OS by AGE. This study provides evidence that AGEs may play a key role in the induction of oxidative stress through the augmentation of PMN-mediated ROS and RNI generation and this may be in part responsible for development of AGE-induced diabetic pathology.