Boron-exposed male workers in Turkey: no change in sperm Y:X chromosome ratio and in offspring's sex ratio.

Boron-associated shifts in sex ratios at birth were suggested earlier and attributed to a decrease in Y- vs. X-bearing sperm cells. As the matter is pivotal in the discussion of reproductive toxicity of boron/borates, re-investigation in a highly borate-exposed population was required. In the present study, 304 male workers in Bandirma and Bigadic (Turkey) with different degrees of occupational and environmental exposure to boron were investigated. Boron was quantified in blood, urine and semen, and the persons were allocated to exposure groups along B blood levels. In the highest ("extreme") exposure group (n = 69), calculated mean daily boron exposures, semen boron and blood boron concentrations were 44.91 ± 18.32 mg B/day, 1643.23 ± 965.44 ng B/g semen and 553.83 ± 149.52 ng B/g blood, respectively. Overall, an association between boron exposure and Y:X sperm ratios in semen was not statistically significant (p > 0.05). Also, the mean Y:X sperm ratios in semen samples of workers allocated to the different exposure groups were statistically not different in pairwise comparisons (p > 0.05). Additionally, a boron-associated shift in sex ratio at birth towards female offspring was not visible. In essence, the present results do not support an association between boron exposure and decreased Y:X sperm ratio in males, even under extreme boron exposure conditions.

Birth weights of newborns and pregnancy outcomes of environmentally boron-exposed females in Turkey.

Boric acid and sodium borates are currently classified as being toxic to reproduction under "Category 1B" with the hazard statement of "H360 FD" in the European CLP regulation. This has prompted studies on boron-mediated reprotoxic effects in male workers in boron mining areas and boric acid production plants. By contrast, studies on boron-mediated developmental effects in females are scarce. The present study was designed to fill this gap. Hundred and ninety nine females residing in Bandirma and Bigadic participated in this study investigating pregnancy outcomes. The participants constituted a study group covering blood boron from low (< 100 ng B/g blood, n = 143) to high (> 150 ng B/g blood, n = 27) concentrations. The mean blood boron concentration and the mean estimated daily boron exposure of the high exposure group was 274.58 (151.81-975.66) ng B/g blood and 24.67 (10.47-57.86) mg B/day, respectively. In spite of the high level of daily boron exposure, boron-mediated adverse effects on induced abortion, spontaneous abortion (miscarriage), stillbirth, infant death, neonatal death, early neonatal death, preterm birth, congenital anomalies, sex ratio and birth weight of newborns were not observed.

Evaluation of FSH, LH, testosterone levels and semen parameters in male boron workers under extreme exposure conditions.

Boric acid and sodium borates are currently classified in the EU-CLP regulation as "toxic to reproduction" under "Category 1B", with hazard statement of H360FD. However, so far field studies on male reproduction in China and in Turkey could not confirm such boron-associated toxic effects. As validation by another independent study is still required, the present study has investigated possible boron-associated effects on male reproduction in workers (n = 212) under different boron exposure conditions. The mean daily boron exposure (DBE) and blood boron concentration of workers in the extreme exposure group (n = 98) were 47.17 ± 17.47 (7.95-106.8) mg B/day and 570.6 ± 160.1 (402.6-1100) ng B/g blood, respectively. Nevertheless, boron-associated adverse effects on semen parameters, as well as on FSH, LH and total testosterone levels were not seen, even within the extreme exposure group. With this study, a total body of evidence has accumulated that allows to conclude that male reproductive effects are not relevant to humans, under any feasible and realistic conditions of exposure to inorganic boron compounds.

Impact of selenium status on Aroclor 1254-induced DNA damage in sperm and different tissues of rats.

Aroclor 1254 is a commercial mixture of polychlorinated biphenyls (PCBs), which are widespread environmental pollutants. It is used as non-flammable heat transfer agent and plasticizer. Animal studies have reported that Aroclor 1254 exerted toxic effects in different organs and systems. Although the evidences are limited, it seems reasonable that Aroclor 1254 may have a potential for similar adverse effects in humans. Selenium (Se) is a trace element and an important component of cellular antioxidant defense. This study was designed to investigate the effects of different Se status on the genotoxicity of Aroclor 1254 in sperm and different organs of Sprague-Dawley rats using Comet assay. Se deficiency (SeD) was generated by feeding 3-week old Sprague-Dawley rats with <0.05 Se mg/kg diet for 5 weeks. Se supplementation groups (SeS) were fed with 1 mg Se/kg diet. Aroclor 1254-treated rats received 10 mg/kg dose by gavage during the last 15 d of feeding period. SeD increased DNA damage in all of the organs as well as in lymphocytes and sperm. Aroclor 1254 treatment caused pronounced changes in liver, kidney and brain cells along with marked increases in lymphocytes and sperm. Se supplementation provided full or partial protection decreases in Aroclor 1254-induced DNA damage in sperm and all of tissues. Se deficiency aggravated the toxicity by increasing DNA damage caused by Aroclor 1254. Further studies should be performed to clarify the mechanism(s) underlying the protective role of Se status against Aroclor 1254 genotoxicity.

Antigenotoxic properties of Paliurus spina-christi Mill fruits and their active compounds.

BACKGROUND: Paliurus spina-christi Mill. (PS) fruits are widely used for different medical purposes in Turkey. Like in many medicinal herbs the studies concerning their activity, the activities of PS are also not well clarified. The aim of this study is to evaluate the antigenotoxicity of the compounds isolated and identified from the extracts of PS fruits. METHODS: The active compounds were separated, isolated, and determined by chromatographic methods and their structural elucidation was performed by Nuclear Magnetic Resonance (NMR) methods. The compounds were obtained from either ethyl acetate (EA) or n-butanol extracts. The cytotoxicities of the compounds using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the antigenotoxic activities of the compounds using the alkaline single cell gel electrophoresis techniques (comet assay) were evaluated in Chinese hamster lung fibroblast (V79) cell lines. RESULTS: The isolated major compounds were identified as (+/-) catechins and gallocatechin from EA fraction and rutin from n-butanol fraction of PS fruits. Their chemical structures were identified by 1H-NMR, 13C-NMR, HMBC, and HMQC techniques. Half-maximal inhibitory concentration of catechins, gallocatechin, and rutin were found to be 734 µg/mL, 220 µg/mL, and 1004 µg/mL, respectively. The methanolic extract of PS (1-100 µg/mL) alone did not induce DNA single-strand breaks while catechins (1-100 µg/mL), gallocatechin (1-50 µg/mL), and rutin (1-50 µg/mL) significantly reduced H2O2-induced DNA damage. CONCLUSION: It has been suggested that PS fruits and their compounds catechins, gallocatechin and rutin may have beneficial effects in oxidative DNA damage. It seems that PS fruits may be used in protection of the disorders related to DNA damage.

Use of in vitro assays to assess the potential cytotoxic, genotoxic and antigenotoxic effects of vanillic and cinnamic acid.

Vanillic acid (VA) found in vanilla and cinnamic acid (CA) the precursor of flavonoids and found in cinnamon oil, are natural plant phenolic acids which are secondary aromatic plant products suggested to possess many physiological and pharmacological functions. In vitro and in vivo experiments have shown that phenolic acids exhibit powerful effects on biological responses by scavenging free radicals and eliciting antioxidant capacity. In the present study, we investigated the antioxidant capacity of VA and CA by the trolox equivalent antioxidant capacity (TEAC) assay, cytotoxicity by neutral red uptake (NRU) assay in Chinese Hamster Ovary (CHO) cells and also the genotoxic and antigenotoxic effects of these phenolic acids using the cytokinesis-blocked micronucleus (CBMN) and the alkaline comet assays in human peripheral blood lymphocytes. At all tested concentrations, VA (0.17-67.2 µg/ml) showed antioxidant activity but CA (0.15-59.2 µg/ml) did not show antioxidant activity against 2,2-azino-bis (3-ethylbenz-thiazoline-6-sulphonic acid) (ABTS). VA (0.84, 4.2, 8.4, 16.8, 84 and 168 µg/ml) and CA (0.74, 3.7, 7.4, 14.8, 74, 148 µg/ml) did not have cytotoxic and genotoxic effects alone at the studied concentrations as compared with the controls. Both VA and CA seem to decrease DNA damage induced by H2O2 in human lymphocytes.

MCM3AP and POMP Mutations Cause a DNA-Repair and DNA-Damage-Signaling Defect in an Immunodeficient Child.

Immunodeficiency patients with DNA repair defects exhibit radiosensitivity and proneness to leukemia/lymphoma formation. Though progress has been made in identifying the underlying mutations, in most patients the genetic basis is unknown. Two de novo mutated candidate genes, MCM3AP encoding germinal center-associated nuclear protein (GANP) and POMP encoding proteasome maturation protein (POMP), were identified by whole-exome sequencing (WES) and confirmed by Sanger sequencing in a child with complex phenotype displaying immunodeficiency, genomic instability, skin changes, and myelodysplasia. GANP was previously described to promote B-cell maturation by nuclear targeting of activation-induced cytidine deaminase (AID) and to control AID-dependent hyperrecombination. POMP is required for 20S proteasome assembly and, thus, for efficient NF-κB signaling. Patient-derived cells were characterized by impaired homologous recombination, moderate radio- and cross-linker sensitivity associated with accumulation of damage, impaired DNA damage-induced NF-κB signaling, and reduced nuclear AID levels. Complementation by wild-type (WT)-GANP normalized DNA repair and WT-POMP rescued defective NF-κB signaling. In conclusion, we identified for the first time mutations in MCM3AP and POMP in an immunodeficiency patient. These mutations lead to cooperative effects on DNA recombination and damage signaling. Digenic/polygenic mutations may constitute a novel genetic basis in immunodeficiency patients with DNA repair defects.

The effects of season and gender on the serum aflatoxins and ochratoxin A levels of healthy adult subjects from the Central Anatolia Region, Turkey.

PURPOSE: This study was undertaken to determine the effects of season and gender on serum aflatoxin (AF) levels (AFG1, AFB1, AFG2 and AFB2) and ochratoxin A (OTA) concentrations of healthy adult population living in Central Anatolia Region of Turkey. METHODS: AF levels were measured by high-performance liquid chromatography (HPLC) and OTA levels were measured by enzyme-linked immunosorbent assay (ELISA) in serum samples of healthy adults (n = 233). RESULTS: In summer and winter, total AF levels in females were 0.98 ± 0.10 and 0.94 ± 0.12 ng/ml and in males 1.35 ± 0.17 and 0.93 ± 0.11 ng/ml, respectively. Male subjects had significantly higher serum total AF levels in summer compared with females (~38%). There was no marked seasonal change in AFG1, AFB1 and AFG2 concentrations in the whole population, except AFB2. Both of the genders had significantly higher OTA levels in winter compared with summer (~60%). CONCLUSIONS: Overall results suggest that Central Anatolia residents are continuously exposed to AFs and OTA. Besides, season and gender can be effective in mycotoxin exposure.

Modulation of the poly (ADP-ribose) polymerase inhibitor response and DNA recombination in breast cancer cells by drugs affecting endogenous wild-type p53.

Synthetic lethal interactions between poly (ADP-ribose) polymerase (PARP) and homologous recombination (HR) repair pathways have been exploited for the development of novel mono- and combination cancer therapies. The tumor suppressor p53 was demonstrated to exhibit indirect and direct regulatory activities in DNA repair, particularly in DNA double-strand break (DSB)-induced and replication-associated HR. In this study, we tested a potential influence of the p53 status on the response to PARP inhibition, which is known to cause replication stress. Silencing endogenous or inducibly expressing p53 we found a protective effect of p53 on PARP inhibitor (PARPi)-mediated cytotoxicities. This effect was specific for wild-type versus mutant p53 and observed in cancer but not in non-transformed cell lines. Enhanced cytotoxicities after treatment with the p53-inhibitory drug Pifithrinα further supported p53-mediated resistance to PARP inhibition. Surprisingly, we equally observed increased PARPi sensitivity in the presence of the p53-activating compound Nutlin-3. As a common denominator, both drug responses correlated with decreased HR activities: Pifithrinα downregulated spontaneous HR resulting in damage accumulation. Nutlin-3 induced a decrease of DSB-induced HR, which was accompanied by a severe drop in RAD51 protein levels. Thus, we revealed a novel link between PARPi responsiveness and p53-controlled HR activities. These data expand the concept of cell and stress type-dependent healer and killer functions of wild-type p53 in response to cancer therapeutic treatment. Our findings have implications for the individualized design of cancer therapies using PARPi and the potentially combined use of p53-modulatory drugs.

Serum aflatoxin levels of the healthy adult population living in the north and south regions of Turkey.

OBJECTIVE: To determine the serum concentrations of aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2) in the healthy adult population living in both the Black Sea and Mediterranean regions of Turkey and to investigate the regional, seasonal and gender variability in aflatoxins (AF) exposure in these regions. DESIGN: Serum AFB1, AFB2, AFG1 and AFG2 concentrations were analysed by HPLC. Settings In total, four hundred and eighty-four serum samples were analysed. SUBJECTS: Four hundred and eighty-four healthy adult volunteers living in rural areas of the Black Sea and Mediterranean regions of Turkey were studied. RESULTS: The mean serum concentration of total AF in the Black Sea region was 1·33 ppb (min-max 0·15-3·38 ppb) and 0·90 ppb (min-max 0·18-2·48 ppb) for summer and winter, respectively. In the Mediterranean region, the mean serum concentration of total AF was determined as 0·55 ppb (range 0·04-1·72 ppb) for summer and 0·45 ppb (range 0·12-1·43 ppb) for winter. The total AF concentrations in serum samples were statistically higher in summer compared with winter for the two regions. The differences between the regions were statistically significant concerning all samples, with higher total AF concentrations in the Black Sea region. CONCLUSIONS: The overall results suggest that the Turkish population living in these two regions is continuously exposed to AF, particularly in the summer, and that mycotoxin contamination in food should be monitored routinely for food safety and human health.

Modulating effects of pycnogenol® on oxidative stress and DNA damage induced by sepsis in rats.

The aim of this study was to evaluate the protective effects of Pycnogenol® (Pyc), a complex plant extract from the bark of French maritime pine, on oxidative stress parameters (superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities and total glutathione (GSH) and malondialdehyde (MDA) levels), an inflammatory cytokine (tumor necrosis factor alpha (TNF-α) level) and also DNA damage in Wistar albino rats. Rats were treated with 100 mg/kg intraperitonally Pyc following the induction of sepsis by cecal ligation and puncture. The decreases in MDA levels and increases in GSH levels, and SOD and GPx activities were observed in the livers and kidneys of Pyc-treated septic rats. Plasma TNF-α level was found to be decreased in the Pyc-treated septic rats. In the lymphocytes, kidney, and liver tissue cells of the sepsis-induced rats, Pyc treatment significantly decreased the DNA damage and oxidative base damage using standard alkaline assay and formamidopyrimidine DNA glycosylase-modified comet assay, respectively. In conclusion, Pyc treatment might have a role in the prevention of sepsis-induced oxidative damage not only by decreasing DNA damage but also increasing the antioxidant status and DNA repair capacity in rats.

Antioxidant and antigenotoxic effects of lycopene in obstructive jaundice.

BACKGROUND: Obstructive jaundice, a frequently observed condition caused by obstruction of the common bile duct or its flow and seen in many clinical situations, may end up with serious complications like sepsis, immune depression, coagulopathy, wound breakdown, gastrointestinal hemorrhage, and hepatic and renal failures. Intrahepatic accumulation of reactive oxygen species is thought to be an important cause for the possible mechanisms of the pathogenesis of cholestatic tissue injury from jaundice. Carotenoids have been well described that are able to scavenge reactive oxygen species. Lycopene, a carotenoid present in tomatoes, tomato products, and several fruits and vegetables, have been suggested to have antioxidant activity, so may play a role in certain diseases related to the oxidative stress. The aim of the present study was to determine the effects of lycopene on oxidative stress and DNA damage induced by experimental biliary obstruction in Wistar albino rats. MATERIALS AND METHODS: Daily doses of 100 mg/kg lycopene were given to the bile duct-ligation (BDL) rats orally for 14 days. DNA damage was evaluated by an alkaline comet assay. The levels of aspartate transferase, amino alanine transferase, gamma glutamyl transferase, alkaline phosphatase, and direct bilirubin were analyzed in plasma for the determination of liver functions. The levels of malondialdehyde, reduced glutathione, nitric oxide, catalase, superoxide dismutase, and glutathione S transferase were determined in the liver and kidney tissues. Pro-inflammatory cytokine tumor necrosis factor-alpha level was determined in the liver tissues. Histologic examinations of the liver and kidney tissues were also performed. RESULTS: According to this study, lycopene significantly recovered the parameters of liver functions in plasma, reduced malondialdehyde and nitric oxide levels, enhanced reduced glutathione levels, as well as enhancing all antioxidant enzyme activity in all tissues obtained from the BDL group. Moreover, the parameters of DNA damage in the liver and kidney tissue cells, whole blood cells, and lymphocytes were significantly lower in the lycopene-treated BDL group, compared with the BDL group. CONCLUSIONS: Lycopene significantly reduced the DNA damage, and markedly recovered the liver and kidney tissue injuries seen in rats with obstructive jaundice.

Assessment of immunotoxicity and genotoxicity in workers exposed to low concentrations of formaldehyde.

Formaldehyde (FA), which is an important chemical with a wide commercial use, has been classified as carcinogenic to humans by International Research on Cancer (IARC). The genotoxic and carcinogenic potential of FA has been documented in mammalian cells and in rodents. A recent evaluation by the E.U. Scientific Committee for Occupational Exposure Limits (SCOEL) anticipated that an 8-h time-weighted average exposure to 0.2 ppm FA would not be irritating and not genotoxic in humans. In order to verify this prediction, a field study was performed that aimed at evaluating immune alterations and genetic damage in peripheral lymphocytes of workers in medium density fiberboard plants exposed to a level of FA equivalent to the OEL recommended by SCOEL (0.2 ppm). Subsets of peripheral lymphocytes, immunoglobulins (IgG, IgA, IgM), complement proteins, and tumor necrosis factor-alpha (TNF-α) levels were evaluated. DNA damage of the workers was assessed by the Comet assay. The absolute numbers and the percentages of T lymphocytes and of natural killer cells, and the levels of TNF-α were higher than the controls, whereas IgG and IgM levels were found to be lower in workers. Other examined immunological parameters were not different from those of the controls. There was no increased DNA damage in the workers compared to controls.

Assessment of DNA integrity (COMET assay) in sperm cells of boron-exposed workers.

An extension of a male reproductive study conducted in a boric acid/borate production zone at Bandirma, Turkey, is presented. The relation between DNA-strand breaks (COMET assay, neutral and alkaline version) in sperm cells and previously described sperm quality parameters was investigated in boron-exposed males. A correlation between blood boron levels and mean DNA-strand breaks in sperm was weak, and DNA-strand breaks in sperm were statistically not different between control and exposed groups. Therefore, increasing boron exposures had no additional contribution in addition to already pre-existing DNA-strand breaks in the sperm cells. Weak but statistically significant correlations between DNA-strand breaks and motility/morphology parameters of sperm samples were observed in the neutral version of the COMET assay, while correlations between the same variables were statistically not significant in the alkaline version. A likely reason for these negative results, even in highly exposed humans, is that experimental exposures that had led to reproductive toxicity in animals were significantly higher than any boron exposures, which may be reached under realistic human conditions.

Reproductive toxicity parameters and biological monitoring in occupationally and environmentally boron-exposed persons in Bandirma, Turkey.

Boric acid and sodium borates have been considered as being "toxic to reproduction and development", following results of animal studies with high doses. Experimentally, a NOAEL (no observed adverse effect level) of 17.5 mg B/kg-bw/day has been identified for the (male) reproductive effects of boron in a multigeneration study of rats, and a NOAEL for the developmental effects in rats was identified at 9.6 mg B/kg-bw/day. These values are being taken as the basis of current EU safety assessments. The present study was conducted to investigate the reproductive effects of boron exposure in workers employed in boric acid production plant in Bandirma, Turkey. In order to characterize the external and internal boron exposures, boron was determined in biological samples (blood, urine, semen), in workplace air, in food, and in water sources. Unfavorable effects of boron exposure on the reproductive toxicity indicators (concentration, motility, morphology of the sperm cells and blood levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and total testosterone) were not observed. The mean calculated daily boron exposure (DBE) of the highly exposed group was 14.45 ± 6.57 (3.32-35.62) mg/day. These human exposures represent worst-case exposure conditions to boric acid/borates in Turkey. These exposure levels are considerably lower than exposures, which have previously led to reproductive effects in experimental animals. In conclusion, this means that dose levels of boron associated with developmental and reproductive toxic effects in animals are by far not reachable for humans under conditions of normal handling and use.

An In Vitro Study on the Interactions of Pycnogenol® with Cisplatin in Human Cervical Cancer Cells.

OBJECTIVES: In the treatment of cancer, it is intended to increase the anticancer effect and decrease cytotoxicity using various plant-derived phenolic compounds with chemotherapeutic drugs. Pycnogenol® (PYC), a phenolic compound, has been the subject of many studies. Since the mechanisms of the interactions of PYC with cisplatin need to be clarified, we aimed to determine the effects of PYC on cisplatin cytotoxicity in human cervix cancer cells (HeLa) and to evaluate the genotoxicity of PYC. MATERIALS AND METHODS: The cytotoxicity of cisplatin and PYC was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in HeLa cells for 24 h and 48 h. The effect of PYC against oxidative DNA damage was evaluated using the comet assay. RESULTS: The IC50 values of cisplatin were 22.4 µM and 12.3 µM for 24 h and 48 h, respectively. The IC50 values of PYC were 261 µM and 213 µM for 24 h and 48 h, respectively. For 24 h exposure, PYC significantly reduced the IC50 value of cisplatin at the selected concentrations (15.6-500 µM). For 48 h exposure, PYC did not change the cytotoxicity of cisplatin at concentrations between 15.6 and 125 µM, but significantly reduced it at concentrations of 250 µM and 500 µM. PYC alone did not induce DNA damage at concentrations of 10 µM or 25 µM; however, it significantly induced DNA damage at higher concentrations (50-100 µM). It also significantly reduced H2O2-induced DNA damage at all concentrations studied (10-100 µM). CONCLUSION: Our results suggest that PYC may increase the cisplatin cytotoxicity in HeLa cells at nongenotoxic doses. The results might contribute to the anticancer effect of cisplatin with PYC in cervical carcinoma, but in order to confirm this result further in vitro studies with cancer cell lines and in vivo studies are needed.

An In Vitro Study on the Cytotoxicity and Genotoxicity of Silver Sulfide Quantum Dots Coated with Meso-2,3-dimercaptosuccinic Acid.

OBJECTIVES: Silver sulfide (Ag2S) quantum dots (QDs) are highly promising nanomaterials in bioimaging systems due to their high activities for both imaging and drug/gene delivery. There is insufficient research on the toxicity of Ag2S QDs coated with meso-2,3-dimercaptosuccinic acid (DMSA). In this study, we aimed to determine the cytotoxicity of Ag2S QDs coated with DMSA in Chinese hamster lung fibroblast (V79) cells over a wide range of concentrations (5-2000 µg/mL). MATERIALS AND METHODS: Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and neutral red uptake (NRU) assays. The genotoxic and apoptotic effects of DMSA/Ag2S QDs were also assessed by comet assay and real-time polymerase chain reaction technique, respectively. RESULTS: Cell viability was 54.0±4.8% and 65.7±4.1% at the highest dose (2000 µg/mL) of Ag2S QDs using the MTT and NRU assays, respectively. Although cell viability decreased above 400 µg/mL (MTT assay) and 800 µg/mL (NRU assay), DNA damage was not induced by DMSA/Ag2S QDs at the studied concentrations. The mRNA expression levels of p53, caspase-3, caspase-9, Bax, Bcl-2, and survivin genes were altered in the cells exposed to 500 and 1000 µg/mL DMSA/Ag2S QDs. CONCLUSION: The cytotoxic effects of DMSA/Ag2S QDs may occur at high doses through the apoptotic pathways. However, DMSA/Ag2S QDs appear to be biocompatible at low doses, making them well suited for cell labeling applications.

Preventive role of Pycnogenol® against the hyperglycemia-induced oxidative stress and DNA damage in diabetic rats.

Diabetes mellitus, a complex progressive metabolic disorder, leads to some oxidative stress related complications. Pycnogenol® (PYC), a plant extract obtained from Pinus pinaster, has been suggested to be effective in many diseases including diabetes, cancer, inflammatory and immune system disorders. The mechanisms underlying the effects of PYC in diabetes need to be elucidated. The aim of this study was to determine the effects of PYC treatment (50 mg/kg/day, orally, for 28 days) on the DNA damage and biochemical changes in the blood, liver, and kidney tissues of experimental diabetic rats. Changes in the activities of catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase enzymes, and the levels of 8-hydroxy-2'-deoxyguanosine, total glutathione, malondialdehyde, insulin, total bilirubin, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, high density lipoprotein, low density lipoprotein, total cholesterol, and triglyceride were evaluated. DNA damage was also determined in the whole blood cells and the liver and renal tissue cells using the alkaline comet assay. PYC treatment significantly ameliorated the oxidative stress, lipid profile, and liver function parameters as well as DNA damage in the hyperglycemic rats. The results show that PYC treatment might improve the hyperglycemia-induced biochemical and physiological changes in diabetes.

Evaluation of the DNA damage in lymphocytes, sperm and buccal cells of workers under environmental and occupational boron exposure conditions.

Industrial production and use of boron compounds have increased during the last decades, especially for the manufacture of borosilicate glass, fiberglass, metal alloys and flame retardants. This study was conducted in two districts of Balikesir; Bandirma and Bigadic, which geographically belong to the Marmara Region of Turkey. Bandirma is the production and exportation zone for the produced boric acid and some borates and Bigadic has the largest B deposits in Turkey. 102 male workers who were occupationally exposed to boron from Bandirma and 110 workers who were occupationally and environmentally exposed to boron from Bigadic participated to our study. In this study the DNA damage in the sperm, blood and buccal cells of 212 males was evaluated by comet and micronucleus assays. No significant increase in the DNA damage in blood, sperm and buccal cells was observed in the residents exposed to boron both occupationally and environmentally (p = 0.861) for Comet test in the sperm samples, p = 0.116 for Comet test in the lymphocyte samples, p = 0.042 for micronucleus (MN) test, p = 0.955 for binucleated cells (BN), p = 1.486 for condensed chromatin (CC), p = 0.455 for karyorrhectic cells (KHC), p = 0.541 for karyolitic cells (KLY), p = 1.057 for pyknotic cells (PHC), p = 0.331 for nuclear bud (NBUD)). No correlations were seen between blood boron levels and tail intensity values of the sperm samples, lymphocyte samples, frequencies of MN, BN, KHC, KYL, PHC and NBUD. The results of this study came to the same conclusions of the previous studies that boron does not induce DNA damage even under extreme exposure conditions.

In vitro genotoxicity assessment of dinitroaniline herbicides pendimethalin and trifluralin.

Pendimethalin and trifluralin are widely used dinitroaniline herbicides. Both compounds can be found as residue levels in agricultural products. This study was conducted in order to provide necessary information for the risk assessment of pendimethalin and trifluralin. In this study, reactive oxygen species (ROS) levels were measured to examine the potential of both compounds to induce oxidative damage in Chinese hamster lung fibroblast (V79) cells. Also, the genotoxic effects of pendimethalin and trifluralin at the concentration range of 1-500 µM was determined. Single cell gel electrophoresis (comet) and micronucleus assays were used on human peripheral lymphocytes and V79 cells for the genotoxicity assessment. The cell viability of two dinitroaniline herbicides were determined by the use of neutral red uptake assay on V79 cells. IC50 values were determined as 66 µM and 128 µM for pendimethalin and trifluralin, respectively. They significantly increased ROS levels on V79 cells for 1-24 h. Both herbicides significantly induced the DNA damage and showed genotoxicity on lymphocytes and V79 cells. Micronucleus frequency increased significantly after pendimethalin and trifluralin treatment of the lymphocytes and V79 cells. Therefore, we concluded that both of the herbicides induced the genotoxicity through the activation of oxidative stress pathway and chromosomal damage.