Organochlorine pesticides and epigenetic alterations in thyroid tumors

Purpose

Cancer incidence depends on various factors e.g., pesticide exposures which cause epigenetic alterations. The present research aimed to investigate the organochlorine pesticides (OCPs) impacts on promoter methylation of three tumor-suppressor genes and four histone modifications in thyroid nodules in 61 Papillary thyroid carcinoma (PTC) and 70 benign thyroid nodules (BTN) patients.

Methods

OCPs were measured by Gas chromatography. To identify promoter methylation of TSHR, ATM, and P16 genes, the nested-methylation-specific PCR (MSP) was utilized, and histone lysine acetylation (H3K9, H4K16, and H3K18) and lysine methylation (H4K20) were detected by performing western blot analysis.

Results

Further TSHR methylation and less P16 methylation were observed in PTC than in BTN. No substantial difference was detected for ATM methylation between PTC and BTN groups. Also, OCP dramatically increased the odds ratio of TSHR (OR=3.98, P=0.001) and P16 (OR=5.65, P<0.001) methylation while confounding variables reduced the chances of ATM methylation arising from 2,4-DDE and 4,4-DDT influence. Hypomethylation of H4K20 and hypo-acetylation of H3K9, H4K16, and H3K18 (P<0.001) were observed in PTC samples than BTN. Furthermore, OCPs substantially decreased the odds ratio of H3K9 (OR=3.68, P<0.001) and H4K16 (OR=6.03, P<0.001) acetylation.

Conclusion

The current research indicated that OCPs could contribute to PTC progression by TSHR promoter hypermethylation and decreased acetylation of H3K9 and H4K16. In addition, in PTC patients, assessing TSHR promoter methylation and acetylation of H3K9 and H4K16 could have predictive values.

Organochlorine pesticides induce thyroid tumors through oxidative stress; an in vivo and in silico study

Thyroid disease is one of the most common endocrine problems around the world. Among the numerous factors, exposure to environmental elements such as pesticides is associated with an increase in the incidence of thyroid disorders. The aim of the present study was to investigate the role of organochlorine pesticides (OCPs) in induction of oxidative stress (OS) and development of thyroid tumors. This case-control study was conducted on 61 patients with papillary thyroid carcinoma (PTC), 70 patients with benign thyroid nodules (BTN), and 73 healthy individuals as control. Seven derived OCPs residues measured by gas chromatography (GC), and enzyme activities of acetylcholinesterase (AChE), superoxide dismutase3 (SOD3), catalase (CAT), glutathione peroxidase3 (GPx3) and paraoxonase1 (PON1) and also, non-enzymatic antioxidant including; malondialdehyde (MDA), total antioxidant capacity (TAC), protein carbonyl (PC), and nitric oxide (NO) biomarkers in all participants were investigated. Furthermore, all of the above enzymes were docked against measured OCPs. The results revealed that β-HCH, γ-HCH, 2,4 DDE, 4,4 DDE, 2,4-DDT, and 4,4-DDT levels along with MDA, NO, and PC levels were elevated, while AChE, SOD3, GPx3, CAT, and PON1 activities and TAC levels were decreased in the PTC and BTN groups compared with the control group. Therefore, OCPs might play a role in the development of thyroid tumors through several mechanisms including generation of OS. Importantly, in silico analysis confirmed the in vivo findings.

Organochlorine pesticides, oxidative stress biomarkers, and leukemia: a case-control study

Exposure to pesticides has been linked to an elevated risk of leukemia. The present research aimed to evaluate the relationship between organochlorine (OC) pesticides and biomarkers of oxidative stress in leukemia patients. This work was conducted on 109 patients with leukemia and 109 healthy controls. The serum concentrations of seven derivatives of OCs including alpha-HCH, beta-HCH, gamma-HCH, 2,4-DDT, 4,4-DDT, 2,4-DDE, and 4,4-DDE along with acetylcholinesterase (AChE), glutathione peroxidase (GPx), superoxide dismutase (SOD), paraoxonase-1 (PON1), and catalase (CAT) activities as well as total antioxidant capacity (TAC), nitric oxide (NO), protein carbonyl (PC), and malondialdehyde (MDA) levels were measured in all the subjects. Levels of OCs were remarkably higher in leukemia patients compared to the controls (p < 0.05). In addition, levels of SOD, AChE, GPx, PON-1, and TAC were remarkably lower in leukemia patients compared to controls (p < 0.05). In contrast, MDA, NO, and PC concentrations were higher in leukemia patients than in the controls (p < 0.05). Moreover, the serum level of 4,4-DDE was negatively associated with GPx activity (p = 0.038). Our findings suggest that OCs may play a role in the development of leukemia by disrupting the oxidant/antioxidant balance.

Opium may affect coronary artery disease by inducing inflammation but not through the expression of CD9, CD36, and CD68

The molecular mechanisms of opium action with regard to coronary artery disease (CAD) have not yet been determined. The aim of this study was to evaluate the effect of opium on the expression of scavenger receptors including CD36, CD68, and CD9 tetraspanin in monocytes and the plasma levels of tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ), malondialdehyde (MDA), and nitric oxide metabolites (NO_x) in CAD patients with and without opium addiction. This case-control study was conducted on three groups: (1) opium-addicted CAD patients (CAD + OA, n = 30); (2) CAD patients with no opium addiction (CAD, n = 30); and (3) individuals without CAD and opium addiction as the control group (Ctrl, n = 17). The protein and mRNA levels of CD9, CD36, and CD68 were evaluated by the flow cytometry and quantitative polymerase chain reaction (RT-qPCR) methods, respectively. The consumption of atorvastatin, aspirin, and glyceryl trinitrate was found be higher in the CAD groups compared with the control group. The plasma level of TNF-α was significantly higher in the CAD + OA group than in the CAD and Ctrl groups (p = 0.001 and p = 0.005, respectively). MDA levels significantly increased in CAD and CAD + OA patients in comparison with the Ctrl group (p = 0.010 and p = 0.002, respectively). No significant differences were found in CD9, CD36, CD68, IFN-γ, and NO_x between the three groups. The findings demonstrated that opium did not have a significant effect on the expression of CD36, CD68, and CD9 at gene and protein levels, but it might be involved in the development of CAD by inducing inflammation through other mechanisms.

Effect of an herbal formulation containing Peganum harmala L. and Fraxinus excelsior L. on oxidative stress, memory impairment and withdrawal syndrome induced by morphine

Background: Traditional Persian medicine has introduced effective remedies in opioid dependence care. One of the most widely used remedies is an herbal formulation containing Peganum harmala L. and Fraxinus excelsior L. (HF). This study investigated the effects of HF to attenuate the withdrawal signs and rewarding effects in morphine-dependent rats.Methods: Forty-nine male Wistar rats were randomly divided into seven groups. The control and vehicle groups received normal saline and sodium carboxymethyl cellulose, respectively. The morphine group received morphine for one week. The single and daily dose of HF groups received morphine similar to the morphine group, and HF (1.4 and 2.8 g/kg) once a day in the daily dose group and only on the last day of the experiment in the single dose of HF group. Finally, the withdrawal signs as well biochemical tests were evaluated. The behavioral parameters were assessed by conditioned place preference (CPP), elevated plus-maze and Y-maze tests. The antioxidant activity of HF was evaluated by measurement of serum contents of malondialdehyde, stable nitric oxide metabolites and total antioxidant capacity (TAC). Moreover, the protein expression of c-fos was assessed by western blotting.Results: Daily treatment with HF significantly reduced the score of CPP behavioral test, all of the withdrawal signs, TAC and the c-fos protein level.Conclusions: The results indicated that HF might be a promising complementary treatment in reducing morphine-induced physical and psychological dependence probably through modulation of c-fos protein expression.

Organochlorine and organophosphorus pesticides may induce brain cancer through oxidative stress

In this study, oxidative stress was investigated as the possible mechanism of action of organochlorine pesticides (OCPs) and organophosphorus pesticides (OPPs) in primary brain tumors (PBT). The levels of seven OCP residues and enzymatic antioxidant biomarkers including erythrocyte acetylcholinesterase (AChE), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and paraoxonase-1 (PON-1) along with non-enzymatic oxidative biomarkers including malondialdehyde (MDA), protein carbonyl (PC), total antioxidant capacity (TAC), and nitric oxide (NO) were measured in blood samples of 73 patients with PBT and 104 healthy controls. A significant association was found between farming activities and PBT (55% of patients were engaged in farming activities while 45% had no farming experience). The mean levels of β-HCH, γ-HCH, 2,4 DDE, 4,4 DDE, 4,4 DDT, MDA, PC, NO, SOD, CAT, and GPx were significantly higher in PBT patients, whereas the levels of TAC, PON-1, and AChE were significantly lower in these patients. Regression analysis showed that PBT was correlated with β-HCH, γ-HCH, 2,4 DDE, 4,4 DDE, and 4,4 DDT. Based on these results, it can be concluded that OCPs and OPPs may play a role in PBT development through the formation of reactive oxygen species (ROS) and promoting oxidative stress.

Occupational exposure to pesticides in farmworkers and the oxidative markers

Organophosphate (OPPs) and organochlorine pesticides (OCPs) are the two predominant forms of pesticides extensively used all around the world and are being reconsidered as environmental pollutants. The current study sought to assess the role of socioeconomic factors on the level of pesticides residues and the oxidative effects of exposure to OPPs and OCPs among the farmworkers of southeast Iran. In this cross-sectional study, 192 farmworkers and 74 non-farmworkers (controls) were involved. Gas chromatography (GC) was performed to measure the serum levels of organochlorine chemicals (2,4-DDT, 4,4-DDT, 2,4-DDE, 4,4-DDE, α-HCH, β-HCH, and γ-HCH). Furthermore, acetylcholinesterase (AChE) activity, arylesterase activity of paraoxonase-1 (PON-1), and several oxidative stress (OS) markers were assessed. In addition, the impact of several parameters such as home to farm distance, education level, ventilation status, and personal protective equipment (PPE) on pesticide levels was analyzed. The levels of OCPs in the farmworkers were significantly higher than the control subjects. In addition, AChE activity, arylesterase activity of PON-1, and total antioxidant capacity in farmworkers were significantly less, and MDA levels were higher than the controls. Education level was associated with farmworkers' protective behavior. The current findings suggested that some phased out OCPs can still be measured in human samples in the southeast of Iran. Furthermore, the current study demonstrated that exposure to OCPs and OPPs was accompanied by adverse consequences regarding OS parameters and subsequent health problems. In addition, the findings of the present study suggest that improving farmworkers' education might be associated with reduced exposure to pesticides and less adverse health effects.

Organochlorine pesticides, oxidative stress biomarkers, and leukemia: a case-control study

Exposure to pesticides has been linked to an elevated risk of leukemia. The present research aimed to evaluate the relationship between organochlorine (OC) pesticides and biomarkers of oxidative stress in patients with leukemia. This work was conducted on 109 patients with leukemia and 109 healthy controls. The serum concentrations of seven derivatives of OCs including alpha-hexachlorocyclohexane (HCH), beta-HCH, gamma-HCH, 2,4-dichlorodiphenyltrichloroethane (DDT), 4,4-DDT, 2,4-dichlorodiphenyldichloroethylene (DDE), and 4,4-DDE along with acetylcholinesterase (AChE), glutathione peroxidase (GPx), superoxide dismutase (SOD), paraoxonase-1 (PON1), and catalase (CAT) activities as well as total antioxidant capacity (TAC), nitric oxide (NO), protein carbonyl (PC), and malondialdehyde (MDA) levels were measured in all the subjects. Levels of OCs were remarkably higher in patients with leukemia compared with the controls (p<0.05). In addition, levels of SOD, AChE, GPx, PON1, and TAC were remarkably lower in patients with leukemia compared with controls (p<0.05). In contrast, MDA, NO, and PC concentrations were higher in patients with leukemia than in the controls (p<0.05). Moreover, the serum level of 4,4-DDE was negatively associated with GPx activity (p=0.038). Our findings suggest that OCs may play a role in the development of leukemia by disrupting the oxidant/antioxidant balance.

CCR2 and DPP9 expression in the peripheral blood of COVID-19 patients: Influences of the disease severity and gender

Introduction

Hyper-inflammatory reactions play a crucial role in the pathogenesis of the severe forms of COVID-19. However, clarification of the molecular basis of the inflammatory-related factors needs more consideration. The aim was to evaluate the gene expression of two fundamental molecules contributing to the induction of inflammatory like CCR2 and DPP9 in cells from peripheral blood samples from patients with various patterns of COVID-19.

Methods

Peripheral blood samples were collected from 470 patients (235 male and 235 female) with RT-qPCR-confirmed COVID-19 test exhibiting moderate, severe, and critical symptoms based on WHO criteria. 100 healthy subjects (50 male and 50 female) were also enrolled in the study as a control group. The gene expression of DPP-9 and CCR-2 was assessed in the blood samples using real-time PCR method.

Results

The COVID-19 patients in severe stage expressed higher levels of CCR2 and DPP9 compared with healthy controls. In male and female patients, the levels of CCR2 and DDP9 expression significantly differed between moderate, severe, and critical patterns (p < 0.0001) as well as between each COVID-19 form and control group (p < 0.0001). The male patients with severe COVID-19 expressed greater levels of CCR2 and DPP-9 than female with same disease form. The female patients with moderate and critical COVID-19 expressed greater levels of CCR2 and DPP-9 than male patients with same disease stage.

Conclusion

We demonstrated that the expression of DPP-9 and CCR-2 was substantially increased in COVID-19 patients with different forms of disease. Considerable differences were also demonstrated between male and female with different patterns of disease. Therefore, we suggest to consider the gender of patients and disease severity for management of COVID-19.

Effects of trehalose on NFE2L2, catalase, and superoxide dismutase in the kidney of aged rats

Aging is associated with an increase in oxidative stress, which damages organs such as the kidney. Trehalose has abundant beneficial activities including antioxidative effects. This study aimed to investigate the effects of trehalose on several antioxidant parameters of the aged kidney. Wistar rats were divided into three groups: young (4 months), aged (24 months), and aged-trehalose. The third group was treated with 2% trehalose for one month. The expression of target genes and enzyme activities in the kidney of the animals were evaluated by quantitative polymerase chain reaction (qPCR) and enzyme colorimetric procedures, respectively. Protein levels of NFE2L2 showed a 50% reduction in aged rats compared to young rats (P<0.001), which was restored by trehalose intervention. In addition, the activity and mRNA levels of catalase (CAT) increased in aged rats while treatment with trehalose reversed this trend. On the other hand, superoxide dismutase (SOD) activity was reduced in the kidneys of aged rats but was not affected by trehalose intervention .It is concluded that trehalose supplementation alleviates the antioxidant system impairments in the kidneys of aged rats. However, further investigations are needed to thoroughly describe the antioxidative impacts of trehalose on the kidneys during aging.

Opium may affect coronary artery disease by inducing inflammation but not through the expression of CD9, CD36, and CD68

The molecular mechanisms of opium with regard to coronary artery disease (CAD) have not yet been determined. The aim of the present study was to evaluate the effect of opium on the expression of scavenger receptors including CD36, CD68, and CD9 tetraspanin in monocytes and the plasma levels of tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ), malondialdehyde (MDA), and nitric oxide metabolites (NO_x) in patients with CAD with and without opium addiction. This case-control study was conducted in three groups: (1) opium-addicted patients with CAD (CAD+OA, n=30); (2) patients with CAD with no opium addiction (CAD, n=30); and (3) individuals without CAD and opium addiction as the control group (Ctrl, n=17). Protein and messenger RNA (mRNA) levels of CD9, CD36, and CD68 were evaluated by flow cytometry and reverse transcription-quantitative PCR methods, respectively. Consumption of atorvastatin, aspirin, and glyceryl trinitrate was found to be higher in the CAD groups compared with the control group. The plasma level of TNF-α was significantly higher in the CAD+OA group than in the CAD and Ctrl groups (p=0.001 and p=0.005, respectively). MDA levels significantly increased in the CAD and CAD+OA groups in comparison with the Ctrl group (p=0.010 and p=0.002, respectively). No significant differences were found in CD9, CD36, CD68, IFN-γ, and NO_x between the three groups. The findings demonstrated that opium did not have a significant effect on the expression of CD36, CD68, and CD9 at the gene and protein levels, but it might be involved in the development of CAD by inducing inflammation through other mechanisms.

Pesticide exposure and related health problems among farmworkers' children: a case-control study in southeast Iran

Pesticides are potentially hazardous chemicals that can cause injury to human health and the environment. The purpose of this study was to evaluate organophosphate pesticides (OPPs) and organochlorine pesticides (OCPs) exposure in farmworkers' children aged 6 to 11 years in Jiroft city in southeastern Iran. One hundred twenty farmworkers' children as case and 53 non-farmworkers' children aged 6 to 11 years as control were selected and the serum levels of OCPs were measured by using gas chromatography in all participants. In addition, erythrocyte acetylcholinesterase (AChE) and arylesterase activity of paraoxonase-1 (PON-1) were measured to evaluate OPPs effects. Catalase (CAT), superoxide dismutase3 (SOD3), glutathione peroxidase (GPx3) activities, and the levels of serum malondialdehyde (MDA), total antioxidant capacity (TAC), nitric oxide (NO), and protein carbonyl (PC) were measured to investigate OCPs and OPPs effects on oxidative stress (OS). The serum levels of beta-HCH, 4,4 DDE, and 4,4 DDT in the case group were significantly higher than the control group. In addition, in the case group, AChE, PON-1, CAT, SOD3, and GPx3 activities and the levels TAC were significantly lower, while MDA, PC, and NO levels were significantly higher than the control group. OCPs as illegal pesticides are present in southeast Iran and children are exposed to OCPs and OPPs in the studied area. In addition, higher serum levels of pesticides may be a major contributor in OS development, as a cause of many diseases.

Pesticide exposure and related health problems among family members of farmworkers in southeast Iran. A case-control study

BACKGROUND

Pesticides used in agriculture are some of the most common pollutants in the world. This study aimed to investigate the effects of Organophosphorus Pesticides (OPPs) and Organochlorine Pesticides (OCPs) on the families of farmworkers in the southeast of Iran.

METHODS

In the present case-control study, 141 family members of farmworkers (as the case group) and 59 family members of non-farmworkers (as the controls) were recruited. Serum levels of OCPs such as α-HCH, β-HCH, γ-HCH, 2,4-DDE, 4,4-DDE, 2,4-DDT, and 4,4-DDT were determined. In addition, erythrocyte acetylcholinesterase (AChE) activity, malondialdehyde (MDA), total antioxidant capacity (TAC), protein carbonyl (PC), nitric oxide (NO) serum levels, arylesterase activity of paraoxonase 1 (PON-1), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activity were determined in all participants. Furthermore, distance to farmlands, education, crops, type, and the number of consumed fruits were evaluated for each individual separately.

RESULTS

The erythrocyte AChE activity and serum activities of GPx, SOD, and PON-1 and TAC levels were significantly decreased, whereas the concentration of MDA, PC, NO, and seven OCPs were significantly increased in the farmworkers' families as compared to the controls. Spearman correlation and linear regression suggest that OCPs increase the oxidative stress in farmworkers' family members. Moreover, distance, education, farming precedence, products, and ventilation had significant effects on the OCP levels and increased the odds ratio of OCP levels in farmworkers' families.

CONCLUSION

With regards to the data obtained in this study, it was revealed that OCPs as illegal pesticides and OPPs were higher than expected in the farmworkers' family members. Furthermore, exposure to OCPs and OPPs, apart from the other effects on the body, leads to oxidative stress (OS) that may cause serious diseases in the exposed populations.

Can Estradiol and Ghrelin Play a Protective Role in Epithelial Ovarian Cancer Incidence in Postmenopausal Women?

OBJECTIVE

The present study aimed to investigate the association between estradiol, n-octanoylated, des-octanoylated, total ghrelin, and ghrelin/des-octanoylated ghrelin ratio levels along with pathological parameters and epithelial ovarian cancer (EOC) odds in postmenopausal women.

MATERIALS AND METHODS

A case-control study was carried out on 45 patients with EOC and 33 age-matched postmenopausal women as the control group. Plasma levels of estradiol, n-octanoylated, des-octanoylated, and total ghrelin were measured by ELISA method.

RESULTS

Estradiol's plasma levels were significantly higher in patients with EOC than in control women (p <0.001). Although the ratio levels of n-octanoylated, des-octanoylated, total ghrelin, and ghrelin/des-octanoylated ghrelin were not associated with EOC in logistic regression models, estradiol levels were significantly related to the increase in EOC odds (OR: 1.083, 95% CI: 1.037-1.13, p <0.001). However, estradiol levels in the two first quartiles (Q₁, Q₂) were associated with decreased odds of EOC (OR: 0.011, 95% CI: 0.001-0.118, p <0.001, and OR: 0.030, 95% CI: 0.003-0.284, p = 0.002, respectively). For those patients in the third quartile of plasma des-octanoylated and total ghrelin compared to those in the highest (Q4), the multivariate odds ratios of EOC were respectively 0.192 and 0.25.

CONCLUSION

In conclusion, higher concentrations of des-octanoylated and total ghrelin might be associated with the decreased EOC odds. Furthermore, the findings suggest that high levels of estradiol might be a potential odds factor in EOC, however, lower estradiol levels may have a protective effect on EOC development.

The effects of malvidin on oxidative stress parameters and inflammatory cytokines in LPS-induced human THP-1 cells

Malvidin is an anthocyanin which is involved in inhibiting inflammatory-related mediators in inflammatory diseases; however, its mechanism of action in THP-1 cells is not yet known. THP-1 is a human monocytic cell line that is derived from patients with acute monocytic leukemia. The present study aimed to investigate the effect of malvidin on inflammatory responses and oxidative stress in lipopolysaccharide (LPS)-induced THP-1 cells. THP-1 cells were stimulated with LPS (50 ng/ml) to induce inflammation in the presence or absence of malvidin. The anti/proinflammatory cytokines were evaluated by real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Total protein levels/phosphorylation of c-Jun N-terminal kinase (JNK), P65-NF-κB, and IKKα/IKKβ were evaluated by western blot analysis. Malondialdehyde (MDA) and nitric oxide (NO) metabolite levels, ferric reducing antioxidant power (FRAP), total thiol (T-SH) content, and superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity were measured to evaluate the antioxidant activity of malvidin in THP-1 cells. Treatment of LPS-stimulated THP-1 cells with malvidin (100 and 200 μM) led to the significant inhibition of interleukin-6 (IL-6), tumor necrosis factor-α, and IL-1β messenger RNA (mRNA) expression and protein levels as well as a significant increase in the IL-10 mRNA expression and protein secretion. Moreover, 200 μM malvidin treatment reduced the phosphorylation of JNK, IKKα/IKKβ, and P65-NF-κB. These findings showed that malvidin not only decreased the MDA and NO metabolite levels but also increased the FRAP and T-SH content as well as SOD and GPx activities. The findings of the present study demonstrated the potential role of malvidin in blocking inflammation and oxidative stress induced by LPS in THP-1 cell line, suggesting that malvidin is likely to be a therapeutic agent for inflammatory diseases.

Evolution of TLR4 role in mediating the hepatoprotective effects of estradiol after traumatic brain injury in male rats

Several studies have shown that 17β-estradiol (E2) exerted beneficial effects on liver disease, and it has a protective impact on brain damage after traumatic brain injury (TBI). TBI-induced liver injury is associated with the activation of TLR4. However, it remains unknown whether E2 can modulate TBI-induced liver injury through TLR4. The objective of this study was to determine the role of TLR4 in hepatoprotective mechanisms of E2 after TBI. Diffuse TBI induced by the Marmarou model in male rats. TAK-242 as a selective antagonist of TLR4 (3 mg/kg) and E2 (33.3 μg/kg) were injected (i.p) respectively 30 min before and 30 min after TBI. The results showed that E2 and TAK-242 markedly inhibited TBI-induced liver injury, which was characterized by decreased aminotransferase activities, inhibition of the oxidative stress, and reduced levels of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and IL-17 in the liver. We also found that TBI induced significant upregulation of TLR4 in the liver, with peak expression occurring 24 h after TBI, and that treatment with E2 significantly inhibited the upregulation of TLR4. Also, both classic [Estrogen receptors alpha (ERα) and beta (ERβ)] and non-classic (G protein-coupled estrogen receptor GPER) E2 receptors are involved in modulating the expression of TLR4. These results suggested that the hepatoprotective effects of estradiol after TBI may be mediated via the downregulation expression of TLR4.

Protective effect of hydralazine on a cellular model of Parkinson’s disease: a possible role of hypoxia-inducible factor (HIF)-1α

Parkinson’s disease (PD) is a neurodegenerative disease accompanied by a low expression level of cerebral hypoxia-inducible factor (HIF-1α). Hence, activating the hypoxia-signaling pathway may be a favorable therapeutic approach for curing PD. This study explored the efficacy of hydralazine, a well-known antihypertensive agent, for restoring the impaired HIF-1 signaling in PD, with the aid of 6-hydroxydopamine (6-OHDA)-exposed SH-SY5Y cells. The cytotoxicity of hydralazine and 6-OHDA on the SH-SY5Y cells were evaluated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] and apoptosis detection assays. The activities of malondialdehyde, nitric oxide (NO), ferric reducing antioxidant power (FRAP), and superoxide dismutase (SOD) were also measured. Expression levels of HIF-1α and its downstream genes at the protein level were assessed by Western blotting. Hydralazine showed no toxic effects on SH-SY5Y cells, at the concentration of ≤50 μmol/L. Hydralazine decreased the levels of apoptosis, malondialdehyde, and NO, and increased the activities of FRAP and SOD in cells exposed to 6-OHDA. Furthermore, hydralazine up-regulated the protein expression levels of HIF-1α, vascular endothelial growth factor, tyrosine hydroxylase, and dopamine transporter in the cells also exposed to 6-OHDA, by comparison with the cells exposed to 6-OHDA alone. In summary, hydralazine priming could attenuate the deleterious effects of 6-OHDA on SH-SY5Y cells by increasing cellular antioxidant capacity, as well as the protein levels of HIF-1α and its downstream target genes.

Serum levels of Organochlorine Pesticides and Breast Cancer Risk in Iranian Women

Breast cancer is a multifactorial disease and its etiology is linked to multiple risk factors. There are shreds of controversial evidence that exposure to organochlorine pesticides (OCPs) are important in the etiology of breast cancer. The present study aimed to determine the circulating levels of OCPs in patients with breast tumors in Southeastern of Iran. This case-control study included 27 patients with malignant breast tumors (MBT), 31 patients with benign breast tumors (BBT), and 27 healthy women as a control group. Serum OCPs levels, including α-hexachlorocyclohexane (α-HCH), β-HCH, γ-HCH, 2,4-dichlorodiphenyltrichloroethane (2,4-DDT), 4,4-DDT, 2,4-dichlorodiphenyldichloroethylene (2,4-DDE), and 4,4-DDE, were measured using gas chromatography. Our data revealed significantly higher concentrations of 2,4-DDT in MBT and BBT groups compared with control ones (P < 0.001 for both comparisons). Patients with breast cancer suffered significantly higher accumulation levels of 4,4-DDE compared with control subjects (P = 0.04). Significant correlations were found among organochlorine compounds with each other in both patients' groups. There was a significant positive correlation between body mass index and serum levels of 2,4-DDT in BBT group (r = 0.407, P = 0.02). The present findings suggest that the serum levels of 4,4-DDE and 2,4-DDT are associated with an increase in the risk of breast cancer in Southeastern women of Iran.

Organochlorine and organophosphorous pesticides may induce colorectal cancer; A case-control study

OBJECTIVES

Among the numerous agents, genetic factors and environmental elements such as pesticides have an important role in colorectal cancer (CRC) incidence. The present study aimed to investigate the probable-role of some organochlorine pesticides (OCPs) and organophosphorous pesticides (OPPs) in patients with CRC.

METHODS

In this case-control study, 42 patients with CRC and 30 healthy subjects were selected. The serum levels of some OCPs (α-HCH, β-HCH, γ-HCH, 2,4 DDE, 4,4 DDE, 2,4DDT and 4,4DDT) were measured by gas chromatography (GC) method. Serum levels of malondialdehyde (MDA), and total antioxidant capacity (TAC) as well as the enzyme activity of acetylcholinesterase (AChE) and arylesterase activity of Paraoxonase-1 (PON-1) were evaluated in all participants. The methylation specific PCR (MSP) assay was used for determining the methylation status of CpG island of p16 and MGMT genes in CRC patients.

RESULTS

The mean serum levels of each OCPs were significantly higher in the patient group compared to the control group (P < 0.001). The AChE and arylesterase activity of PON-1 in the patient group were significantly lower than the control group (P < 0.001). The mean serum levels of MDA and TAC in the serum of the patient group were significantly higher than the control group (P < 0.001 and P < 0.002, respectively). The current findings demonstrated significantly hypermethylation of p16 promoter in CRC patients.

CONCLUSION

Regarding the higher levels of OCPs in CRC patients, along with hypermethylation of the p16 promoter gene, diminishing in AChE and PON-1 activity and increasing in oxidative stress factors, the role of OCPs and OPPs in the CRC progression in the South-East of Iran may be assumed.

CD36 gene polymorphism rs1761667 (G > A) is associated with hypertension and coronary artery disease in an Iranian population

Background

CD36 is associated with regulation of lipid metabolism, atherosclerosis, and blood pressure. Moreover, its variation may be involved in the development of hypertension and/or coronary artery disease (CAD). The present study was conducted to investigate the possible association of CD36 rs1761667 (G > A) polymorphism with hypertension and/or CAD in the southeastern of Iran.

Methods

The present observational study was composed of 238 subjects who were admitted for coronary angiography, and divided into four groups: 1) hypertensive without CAD (H-Tens, n = 52); 2) hypertensive with CAD (CAD + H-Tens, n = 57); 3) CAD without hypertension (CAD, n = 65); and 4) non-hypertensive without CAD as the control group (Ctrl, n = 64). The CD36 rs1761667 polymorphism was genotyped with PCR-RFLP method. Association between CD36 rs1761667 genotypes and the risk of CAD and hypertension was assessed using multinomial regression by adjusting for age, sex, creatinine, fasting blood sugar (FBS), systolic blood pressure (SBP) and diastolic blood pressure (DBP).

Results

In the present study, minor allele (A) frequency was 0.36. The genotype, but not allele frequency of the CD36 rs1761667 was significantly different between the four study groups (p = 0.003). Furthermore, using a recessive inheritance model CD36 rs1761667 polymorphism was significantly associated with an increased risk of CAD with hypertension (OR = 5.677; 95% CI = 1.053–30.601; p = 0.043). However, using the dominant model of CD36 rs1761667 had a protective effect on H-Tens and CAD patients.

Conclusion

The present findings revealed an association between CD36 rs1761667 polymorphism and susceptibility to hypertension and/or CAD in a southeastern Iranian population.

Assessment of hormonal alterations in major depressive disorder: A clinical study

Major depressive disorder (MDD) is a severe mood disorder that may lead to use of drugs, alcohol, and even suicide in acute cases. It has been shown that neurotransmitters and hormones have the same receptors and pathways in the mood area of the brain. Therefore, metabolic and biochemical changes are expected in MDD and, in such diseases, understanding the hormonal alterations would be extremely helpful in the management or treatment with hormone replacement therapy. We evaluated levels of cortisol, adrenocorticotropic hormone (ACTH), testosterone, thyroid-stimulating hormone (TSH), thyroxine (T4), triiodothyronine (T3), free thyroxine index (FT4I), T3 resin uptake (T3RU), and dehydroepiandrosterone sulfate (DHEA-S) in 79 patients suffering from MDD and 71 healthy controls. The existence of MDD was confirmed by a face-to-face structured clinical interview. We started the investigation by taking a blood sample from the study population. Then, hormone levels were measured by enzyme-linked immunosorbent assay. Significant differences were found between TSH, FT4I, DHEA-S, ACTH, testosterone, and cortisol/DHEA-S ratio in MDD patients compared to the healthy controls. We also demonstrated a correlation between MDD recurrence and FT4I index and TSH, respectively. Regarding some hormonal changes in patients with MDD, hormonal shifts should be considered in the treatment or management of MDD patients.

Organochlorine and organophosphorus pesticides and bladder cancer: A case-control study

BACKGROUND

Exposure to pesticides is associated with an increase in the incidence of cancer. We aimed to investigate the association of serum organochlorine pesticides (OCPs) and organophosphorus pesticides (OPs) levels and GSTM1/GSTT1 gene polymorphism with bladder cancer (BC).

METHODS

This study was performed on 57 patients with BC and 30 controls (C). Acetylcholinesterase (AChE) activity, arylesterase activity of paraoxonase-1 (ARE), total antioxidant capacity (TAC), and malondialdehyde (MDA) levels were determined in serums of all participants. Genomic DNA was extracted using the salting out method and GSTM1/GSTT1 gene polymorphisms were examined by multiplex polymerase chain reaction assay. Measurement of OCPs (α-hexachlorocyclohexane [α-HCH], β-HCH, γ-HCH, 2,4-dichlorodiphenyltrichloroethane [2,4-DDT], 4,4-DDT, 2,4- dichlorodiphenyldichloroethylene [2,4-DDE], and 4,4-DDE) in serum was carried out using an FID-equipped gas-chromatography system.

RESULTS

AChE activity was significantly lower, ARE activity and TAC were declined but it was not statistically significant, however, α-HCH, γ-HCH, 4,4-DDE, 2,4-DDT, and 4,4-DDT pesticides, and MDA were significantly higher in BC patients compared with the control subjects. Also, a positive correlation was found between the number of smoked cigarettes and the years of smoking with BC development. There was no association between GSTM1/GSTT1 gene polymorphisms and OCPs in BC patients.

CONCLUSION

Due to the higher levels of some OCPs in the BC patients, along with the reduction in AChE activity and increased MDA levels, it may be concluded that OCPs and OPs play an important role in the induction of BC in southeastern Iran.

Epigenetic modulation of BRCA-1 and MGMT genes, and histones H4 and H3 are associated with breast tumors

Aberrant patterns in promoter methylation of tumor-suppressor genes and posttranslational modifications of histone proteins are considered as major features of malignancy. In this study, we aimed to investigate promoter methylation of three tumor-suppressor genes (BRCA-1, MGMT, and P16) and three histone marks (H3K9ac, H3K18ac, and H4K20me3) in patients with breast tumors. This case-control study included 27 patients with malignant breast tumors (MBT) and 31 patients with benign breast tumors (BBT). The methylation-specific PCR was used for determining promoter methylation of BRCA-1, MGMT, and P16 genes. Western blot analysis was performed to detect histone lysine acetylation (H3K9ac and H3K18ac) and lysine methylation (H4K20me3). BRCA-1 promoter methylation was detected in 44.4% of the MBT whereas this alteration was found in 9.7% of BBT (P = 0.005). The Kaplan-Meier analysis indicated that hypermethylation in BRCA-1 promoter was significantly associated with poor overall survival of patients with breast cancer (P = 0.039). MGMT promoter methylation was identified in 18.5% of MBT and 0.0% of the BBT (P = 0.01). The frequency of P16 promoter methylation was 25.8% in BBT and 11.1% in MBT (P = 0.12). As compared with BBT, MBT samples displayed the aberrant patterns of histones marks with hypomethylation of H4K20 and hypoacetylation of H3K18 (P = 0.03 and P = 0.04, respectively). There was a negative significant correlation between H3K9ac levels and tumor size in MBT group (r = -0.672; P = 0.008). The present findings suggest that promoter hypermethylation of MGMT and BRCA-1 genes along with alterations in H3K18ac and H4K20me3 levels may have prognostic values in patients with breast cancer. Moreover, the detection of these epigenetic modifications in breast tumors could be helpful in finding new methods for breast cancer therapy.

Berberis integerrima ameliorates insulin resistance in high- fructose-fed insulin-resistant rats

OBJECTIVES

This study was aimed to investigate the effect of Berberis integerrima (B. integerrima) extract on insulin sensitivity in high-fructose-fed insulin-resistant rats.

MATERIALS AND METHODS

Experimental rats were randomly divided into two groups: the control group was fed a regular chow diet while other group fed with a high-fructose diet for 8 weeks. After the first six weeks, the animals were treated with B. integerrima extract or pioglitazone for two weeks. Insulin and adiponectin levels were measured by ELISA. Additionally, Insulin resistance was calculated using a Homeostasis Model Assessment of Insulin resistance (HOMA-IR). The plasma free fatty acid (FFA) profile was obtained by gas chromatography. PPARγ and GLUT4 gene expression were assessed by real-time polymerase chain reaction (PCR) and western-blotting.

RESULTS

Comparing the B. integerrima treated group with the control group, weight gain (P=0.009) and levels of insulin (P=0.001), blood glucose (P<0.0001), and HOMA-IR (P<0.0001) were significantly reduced. Additionally, the adiponectin concentration was significantly increased (P<0.0001). Among the FFA fractions, the mean concentration of palmitoleic acid and stearic acid in the B. integerrima group were significantly higher than the control group (P<0.0001 and P=0.005, respectively). However, there was no significant difference at the mRNA and protein level of GLUT4 and PPAR-γ between B. integerrima treated group and control group.

CONCLUSION

The study findings revealed that B. integerrima might be a protective candidate against Type 2 diabetes/insulin resistance through direct insulin-like effect and an increase in adiponectin levels. However, the mechanism of B. integerrima was independent of GLUT4 and PPARγ.

Mass rearing of Lucilia sericata Meigen (Diptera: Calliphoridae)

OBJECTIVE

To carry out an experimental study with the main objective of mass rearing of sheep flies (Lucilia sericata).

METHODS

Hand collection and beef- or cattle liver-baited net traps were used for field fly sampling from April, 2010 to November, 2010. The samples collected from different places were placed in properly labeled tubes and sent to the Entomology Laboratory. Since maggot identification is important in inducing mortality, they were kept under insectary condition to develop to adult stage and identified using systematic keys.

RESULTS

A total of 218 flies were collected in three rounds of sampling from the field of Tehran and Karaj Counties. In the first generation, 433 flies including 135 (31.17%) male, and 298 (68.82%) female were yielded. The female/male of parent ratio was calculated as 1.72 in Tehran and in Karaj areas, whereas it was 2.20% and 1.81%, respectively in F1 and F2 generations, respectively.

CONCLUSIONS

During this study, the mass rearing of sheep blow fly has been established at the School of Public Health, Tehran University of Medical Sciences and can be used for producing flies for maggot therapy.

Characterization of the release of DNA by a human leukemia-cell line hl-60

Release of DNA fragments into the culture supernatant of human promyelocytic cell line HL-60 was investigated. The released DNA has previously been shown to have a strong immunosuppressive effect on the proliferation of mitogen-stimulated human peripheral lymphocytes and some cancer cell lines. In this study, HL-60 cells were cultured for four days in serum-free medium and the amount of extracellular nucleic acid was monitored daily. Nucleic acids were isolated by phenol/chloroform extractions, followed by ethanol precipitations. A similar amount of DNA was identified in the HL-60 culture supernatant regardless of whether the cells were incubated for one day or up to four days. Also, the same amount of DNA was isolated from culture supernatants after washing the cells daily and reincubating into the fresh medium. During the first 8 hours of incubation no DNA material was detected in the culture supernatant, whereas at 24 h the concentration of the extracellular DNA reached a plateau. The data suggest the extracellular DNA is not accounted for totally by DNA from dying cells, and a regulatory mechanism may be involved which controls the release of DNA into the medium.

A texture classification method for diffused liver diseases using Gabor wavelets

We proposed an efficient method for classification of diffused liver diseases based on Gabor wavelet. It is well known that Gabor wavelets attain maximum joint space-frequency resolution which is highly significant in the process of texture extraction and presentation. This property has been explored here as the proposed method outperforms the classification rate obtained by using dyadic wavelets and methods based on statistical properties of textures. The feature vector is relatively small compared to other methods. This has a significant impact on the speed of retrieval process. In addition, the proposed algorithm is not sensitive to shift of the image contents. Since shifting the contents of an image will cause a circular shift of the Gabor filter coefficients in each sub-band. The proposed algorithm applied to discriminate ultrasonic liver images into three disease states that are normal liver, liver hepatitis and cirrhosis. In our experiment 45 liver sample images from each three disease states which already proven by needle biopsy were used. We achieved the sensitivity 85% in the distinction between normal and hepatitis liver images and 86% in the distinction between normal and cirrhosis liver images. Based on our experiments, the Gabor wavelet is more appropriate than dyadic wavelets and statistical based methods for texture classification as it leads to higher classification accuracy.

HIV-1 Gag p24-Nef fusion peptide induces cellular and humoral immune response in a mouse model

Many Human immunodeficiency virus (HIV) candidate vaccines have been tested in clinical trials, but none was sufficiently effective in the prevention of HIV infection. A HIV vaccine should induce humoral as well as cell-mediated response, the latter including the cytotoxic CD8+ T lymphocyte (CTL) response. In this study, we immunized BALB/c mice with a purified fusion peptide Gag p24-Nef and evaluated immune responses. As for the cellular responses, the adjuvanted fusion peptide induced lymphocyte proliferation, CTL response, and cytokines IFN-gamma and IL-4 in the Th1 pattern. Humoral immune response to the adjuvanted fusion peptide included an increase in IgG antibodies of more IgG2a than IgG1 subtype. These results indicate that the employed HIV-1 peptide construct can elicit both cellular and humoral immune responses in mice. Further studies aimed at memory T cells and other aspects of immune responses are needed before a comprehensive assessment of this candidate vaccine could be provided.

KEYWORDS

epitopes; fusion peptide; HIV-1 p24-Nef; immune response.

Evaluation of silica gel-immobilized phosphorylcholine columns for size exclusion chromatography and their application in the analysis of the subunit structures of fish-egg lectins

Columns of phosphorylcholine (PC) immobilized on silica gel were shown to be useful for size exclusion chromatography (SEC) of proteins. The columns provided good separation of proteins in 50mM sodium phosphate buffer (pH 6.9) containing 0.25 M NaCl, and there was a linear relationship between the retention times and the logarithmic values of the molecular weights with a correlation coefficient (R(2)) of 0.978-0.992. The columns were used in analyzing the subunit structures of the rhamnose-binding lectins CSL1, CSL2, and CSL3, isolated from chum salmon (Oncorhynchus keta) eggs. Although the lectins, which are a group of carbohydrate-binding and hydrophobic proteins, behaved anomalously in SEC with conventional matrices, they could be eluted from the immobilized PC columns without non-size-related retention, thereby allowing their molecular weights to be reliably estimated.

Nitric oxide induction as a novel immunoepidemiological target in malaria‐infected patients from endemic areas of the Islamic Republic of Iran

OBJECTIVE

Malaria has been prevalent for a long time in Iran and continues to be a health problem despite substantial control programs. In addition to numerous cytokines, nitric oxide (NO) is thought to be a key molecule and a novel target of malaria immunopathology.

MATERIAL AND METHODS

The objective of this research was to measure reactive nitrogen intermediates (RNI) as stable metabolites of NO induction in plasma of malaria-infected patients in Iran. In this study, 235 blood samples from malaria patients and 80 blood samples from healthy controls were randomly collected from different malarial endemic provinces of Iran, located in southeastern (Sistan & Balouchestan, Hormozgan, Kerman) and northwestern (Ardabil) areas. The involvement of NO in malaria patients has been investigated by statistical analysis of RNI values. Griess micro assay (GMA) was used during Plasmodium vivax, P. falciparum and mixed infections, in order to evaluate whether RNI changes are related to the provincial areas, parasite strains, clinical symptoms and age and gender parameters.

RESULTS

The results showed a significant increase of RNI level in malaria patients compared with the control groups of Ardabil (p<0.01), Sistan & Balouchestan, Hormozgan and Kerman (p<0.001) provinces. The level of RNI was higher in mixed plasmodial infection than in single infection.

CONCLUSIONS

The high level of RNI was dependent on the type of infection, the plasmodia strain, the clinical symptoms, the age groups and the endemic provinces. Although, this study did not clarify the pathogenic and/or protective role of NO in malaria, our findings provide a novel immunoepidemiological aspect of basal NO production in patients with malaria in endemic areas in Iran.

Multiresolution analysis of transient evoked otoacoustic emission

To improve transient evoked otoacoustic emission (TEOAE) test accuracy, a new technique in presented based on multiresolution signal decomposition. Using a wavelet function which optimized according to an active cochlear model, time frequency distribution of TEOAE is obtained. The coefficients of the filter bank are determined from Morlet mother wavelet function in the analysis section. In the synthesis section, time windows are obtained from deduced latency curve. By applying this multiresolution analysis, the correlative noise would be canceled. Therefore, the wave reproducibility can be increased without loss of measuring reliability. In abnormal cases where response is not expected the correlative noise is considered as response are completely disappeared. Thus this will increase the accuracy of screening results.

Development of mixed Th1/Th2 type immune response and protection against Mycobacterium tuberculosis after rectal or subcutaneous immunization of newborn and adult mice with Mycobacterium bovis BCG

Cell-mediated immunity plays a key role in containing the growth of Mycobacterium tuberculosis in the host. The induction of an antibody response or a mixed cell-mediated and humoral response is frequently associated with tuberculosis disease or a decrease in the ability to control M. tuberculosis load. We recently reported the induction of similar immune responses and protection by rectal, subcutaneous (SC) or intradermal administration of Mycobacterium bovis BCG in adult mice, guinea pigs and macaques. The rectal immunization, which did not induce the side-effects associated with parenteral routes (axillary adenitis) and which could be used to reduce the risks of viral transmission associated with unsafe injections in the developing world, was analysed and compared in newborn and adult BALB/c mice. The rectal and SC immunization induced, in mice immunized as newborns or as adults, a mixed T helper 1/T helper 2 (Th1/Th2) immune response; however, particularly in adult mice, after SC administration of BCG, the level of Th2 immune response is significantly higher than it is by the rectal route. Six months after immunization with BCG, rectal and SC delivery induced similar levels of protective immunity against a virulent challenge with M. tuberculosis strain (H37Rv) in mice immunized as adults, but the rectal BCG delivery triggered stronger protection than the SC delivery if mice were immunized as newborns.

Compositional changes of PBL population in patients with chronic hepatitis B virus infection

In this report we have analysed the peripheral blood lymphocyte of several patients with chronic hepatitis B virus infection with flow cytometry. Based on the presence and absence of the HBeAb, patients were divided into two groups. In both, all the patients were HBsAg positive with normal range of serum alanine aminotranferase (23.9 +/- 17.8). We have found that the immunophenotypic profiles of patients were different from healthy donors with significant decrease in CD(3)(+) T cells, specially CD(8)(+) T cells and a significant increase in the CD(19)(+) B cells. The differences were seen in other subset of T cells (CD(4)(+)) or NK cells (CD(56)(+)/CD(16)(+)) and HLA-DR markers were not significant. When the phenotypic profiles of both groups were compared with each other, such changes were more dominant in group II, with HBeAb positive than in group I, with HBeAb negative. Also, we have seen a correlation between the increase of CD(19)(+) B cells and the decrease of CD CD(3)(+) T cells. No such correlation was observed with other cells.

Mycobacterium bovis BCG induces similar immune responses and protection by rectal and parenteral immunization routes

We compared cellular immune responses to rectal, subcutaneous, and intradermal administration of Mycobacterium bovis BCG for 5 to 20 weeks in mice, guinea pigs, and macaques. Strong lymphoproliferative responses were induced in spleen cells after in vitro stimulation with purified protein derivative in guinea pigs and macaques, whatever the route of immunization. Comparable high numbers of gamma interferon- and tumor necrosis factor alpha-producing cells were found in the spleen after rectal, subcutaneous, and intradermal immunization of mice and macaques. Similar levels of precursors of cytotoxic T lymphocytes specific for mycobacterial antigens were observed in mice for all immunization routes. In macaques, cytotoxic activity, determined only at the end of the experiment (20 weeks), was similar after rectal and intradermal immunization. Six months after immunization, rectal and subcutaneous routes induced in mice similar levels of protective immunity against challenge with a virulent Mycobacterium tuberculosis strain (H37Rv). Rectal immunization gave immune responses and protective capacity similar to those for parenteral immunization and seemed to be a promising new route of vaccination against tuberculosis; in our study, immunization via the rectal route never induced side effects associated with parenteral routes (axillary adenitis) and could also effectively reduce the risks of viral transmission associated with unsafe injections in the developing world.

Human prostatic-carcinoma cells modulate lymphocyte-proliferation by an immunosuppressive activity

We have identified an immunosuppressive activity from the conditioned medium of an androgen-independent human prostatic carcinoma cell line, JCA-1. This activity is constitutively produced by JCA-1 cells and is capable of suppressing normal human peripheral blood lymphocyte proliferation irreversibly in a dose-dependent manner. Immunosuppressive activity was semi-purified by a combination of ion-exchange chromatography and gel filtration with an apparent molecular weight of 40-55 kDa. The immunosuppressive activity was not cytolytic to lymphocytes and was sensitive to 56 degrees C, reducing agent as well as to protease digestion. Cell cycle analysis revealed that the suppressive activity did not induce apoptosis, but it prevented some G(1) lymphocytes from entering into the S phase of the cell cycle.

Antiproliferative effect of a prostatic cell-derived activity on the human androgen-dependent prostatic carcinoma cell line LNCaP

We have identified a new antiproliferative activity from the conditioned medium of two androgen-independent prostatic cancer cell lines, PC3 and DU-145. This antiproliferative activity selectively inhibited cell proliferation of an androgen-dependent prostate cancer cell line LNCaP in a dose-dependent manner. No antiproliferative activity was observed against mouse fibroblast 3T3, normal human lymphocytes, human leukemic cells, including promyelocyte HL-60 or T cell HUT-78, or human adenocarcinoma cell lines, including prostatic cells JCA-1, ovary NIH:OVCAR-3, cervix C-33A, or breast MDA-MB-231. Cell cycle analysis revealed that the antiproliferative activity did not induce apoptosis in LNCaP cells, but it prevented some G1 LNCaP cells from entering into the S phase of the cell cycle. The antiproliferative activity was sensitive to high temperature (100 degrees C) and to proteinase digestion; however, it was resistant to 56 degrees C, pH 2.0, and reducing agent treatment, as well as to DNase and RNase digestion. The antiproliferative activity was partially purified by gel filtration, ion-exchange chromatography, and SDS-PAGE, with an apparent molecular weight of 50 kD. The antiproliferative activity was not affected by neutralizing antibody against TGF-beta 1,2,3, TNF-alpha, PDGF, EGF, IL-1, IL-2, IL-3, IL-4, or IL-6.

Antigens of Lyme disease of spirochaete Borrelia burgdorferi inhibits antigen or mitogen-induced lymphocyte proliferation

Modulation of cellular immune responses by the spirochaete Borrelia burgdorferi, the bacteria that causes Lyme disease, was demonstrated. When cultured in the presence of sonicated Borrelia preparation (Bb), the mitogen- or antigen-stimulated proliferative responses of normal lymphocytes were consistently lowered. Bb caused the greatest reduction in Concanavalin A (ConA) or antigen-stimulated proliferation, where almost 100% reduction in proliferation could be achieved. Bb also reduced phytohemagglutinin-M (PHA) or pokeweed mitogen (PWM)-stimulated peripheral blood lymphocyte (PBL) proliferation, with the PWM proliferation being the least affected. This regulatory activity was not due to toxicity and was determined to be caused by Bb protein antigens. The degree of the proliferation reduction was directly proportional to both Bb quantity and length of exposure to lymphocytes. IL-2 production was significantly reduced from Bb-exposed lymphocytes. The entry of lymphocytes into the proliferating phases of the cell cycle was also shown to be blocked. These results have demonstrated an immune suppressive mechanism of B. burgdorferi. The magnitude of host immune responses may be dependent on the degree of suppression which is related to the spirochaete quantity and their length of presence in the host.

A murine IgG1 monoclonal antibody that binds specifically to outer surface protein A of Lyme disease spirochete Borrelia burgdorferi

A murine monoclonal antibody, designated MA-2G9, directed against outer surface protein A (OspA) of the Lyme disease spirochete, Borrelia burgdorferi, has been produced. Antibody MA-2G9, IgG1 subclass, was purified by affinity chromatography on protein G Sepharose column and used for purification of OspA antigen from Borrelia burgdorferi cell lysate. Epitope specificity was studied by Western immunoblotting, using several strains of B. burgdorferi and non-Lyme disease bacteria such as Treponema pallidum and B. hermsii. The MA-2G9 monoclonal antibody reacted specifically with recombinant OspA as well as with native OspA in sonicated B. burgdorferi strains. No reaction was observed with T. pallidum, Escherichia coli, Staphylococcus aureus and B. hermsii lysates. The MA-2G9 antibody also recognized the denatured form of OspA indicating that it is directed against sequential epitope and not conformational epitope.

Regulation of human lymphocyte proliferation by a tumour cell-derived DNA fraction

A suppressor activity was isolated and partially purified from culture supernatant of human myeloid leukaemic cell line HL-60 by ion-exchange chromatography, HPLC and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). This activity was capable of suppressing proliferation of mitogen-stimulated normal human lymphocytes in a dose-dependent manner. The suppressor activity was identified as DNA by its typical absorbance at 260 nm, and by its susceptibility to DNase digestion. The DNA with suppressive activity was found to be double-stranded with the molecular weight range between 0.6 and 1.5 kb. This DNA material did not have cytotoxic activity and did not alter interleukin-2 receptor expression. Cell cycle analysis has suggested that DNA molecules could interact with lymphocytes to arrest the stimulated lymphocytes in the G1 phase, apparently preventing the cells from entering into the proliferating S phase.

Purification of an acid-stable bovine leukocyte interferon

Bovine leukocyte interferon (BoL-IFN), produced in bovine peripheral blood leukocytes after priming and induction with Sendai virus, was concentrated by precipitation with KSCN (pH 3.5) and purified by gel column chromatography. Recovery of BoL-IFN from precipitation was higher when crude BoL-IFN containing more fetal bovine serum (FBS) was used. However, purity of BoL-IFN recovered from the gel filtration column was highest when crude BoL-IFN with no FBS was used. The use of 25% ethylene glycol in the column elution buffer resulted in over 93% recovery of the applied IFN activity, versus only 25% when buffer contained no ethylene glycol. Column-purified BoL-IFN was further concentrated by ultrafiltration and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in denaturing buffer. When crude BoL-IFN containing no FBS was used for purification, BoL-IFN from a selected column fraction applied to SDS-PAGE resulted in a single narrow band with an apparent molecular weight (MW) of 19,000 Da. Extraction of the SDS-PAGE gel resulted in a single peak of IFN activity indicating identity of the activity and the polypeptide. This proved to be a practical method for obtaining sufficient quantities of purified natural BoL-IFN for use in the production of monoclonal antibodies to BoL-IFN and other biological experiments.

Purification and characterization of a human leukemia cell-derived immunosuppressive factor

A human leukemia cell-derived suppressor factor (LDSF) capable of suppressing in vitro proliferation and activation of normal human lymphocytes was purified from human leukemic HL-60 cells. LDSF is constitutively produced by the cells and was purified from serum free culture supernatant by a combination of ion-exchange chromatography, gel filtration and electrophoresis. Purified LDSF was determined to be a single chain protein with an apparent molecular mass of 66,000 daltons. LDSF was not cytolytic to lymphocytes, was heat stable at 70 degrees C, and did not have any effect on IL-2 or transferrin receptor expression.