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Abstract: This study was designed to investigate the possible protective effect of lycopene against the renal toxic effects of OTA. Male Sprague-Dawley rats (<200g, n =6) were treated with OTA (0.5mg/kg/day) and/or lycopene (5mg/kg/day) by gavage for 14 days. Histopathological examinations were performed and apoptotic cell death in both cortex and medulla was evaluated by TUNEL assay. Besides, biochemical parameters and activities of renal antioxidant selenoenzymes [glutathione peroxidase 1 (GPx1), thioredoxin reductase (TrxR)], catalase (CAT), superoxide dismutase (SOD); concentrations of total glutathione (GSH), and malondialdehyde (MDA) levels were measured. OTA treatment was found to induce oxidative stress in rat kidney, as evidenced by marked decreases in CAT (35%) activity and GSH levels (44%) as well as increase in SOD activity (22%) vs control group. Furthermore, TUNEL analysis revealed a significant increase in the number of TUNEL-positive cells in cortex (49%) and medulla (75%) in OTA administrated group compared to control (p <0.05). Lycopene supplementation with OTA increased GPx1 activity and GSH levels, and decreased apoptotic cell death in both cortex and medulla vs. control. The results of this study showed that at least one of the mechanisms underlying the renal toxicity of OTA is oxidative stress and apoptosis is the major form of cell death caused by OTA. Besides, our data indicate that the natural antioxidant lycopene might be partially protective against OTA-induced nephrotoxicity and oxidative stress in rat. [Copyright &y& Elsevier]

Abstract: Ochratoxin A (OTA), one of the most prevalent mycotoxins in the world, has nephrotoxic and hepatotoxic properties. Lycopene is an important carotenoid and has a high singlet-oxygen and free-radical scavenging capacity. This study was designed to investigate the possible protective effects of lycopene against the genotoxicity of OTA in rat tissues using the alkaline comet assay. Male Sprague–Dawley rats were used in the experiments. OTA (0.5 mg/kg b.w./day) was administered by gavage for 14 days, whereas lycopene was applied on the last 7 days or for 14 days of the feeding period, with OTA treatment. OTA caused marked increases in tail length, tail moment, and tail intensity vs. control both in the kidney and liver cells, but not in the lymphocytes. Lycopene administration alone for 7 and 14 days did not provide any significant change in DNA damage of the lymphocytes, renal and hepatic cells vs. controls. However, lycopene for both 7 and 14 days, with OTA exposure in renal and hepatic cells, supplied significant decreases in tail length, tail moment, and tail intensity vs. OTA-exposed rats. The effect of 14 days supplementation seemed to be more protective, particularly against hepatic cells. These results suggest that lycopene may protect hepatic and renal tissue from OTA-induced DNA damage. [Copyright &y& Elsevier]

Abstract: In most of the diseases which are considered to benefit from propolis, cellular immune reaction is activated, neopterin levels in body fluids are increased and enhanced tryptophan degradation is observed. In this study, the immunomodulatory effects of six Turkish propolis samples were evaluated by using the in vitro model of peripheral blood mononuclear cells (PBMC). Concentrations of neopterin, tryptophan, kynurenine and pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) were determined and also the viability of the cells was checked with trypan blue and MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] test. In PBMC treated with mitogen phytohaemagglutinin, neopterin production and tryptophan degradation by enzyme indoleamine 2,3-dioxygenase (IDO) as well as release of cytokines was significantly enhanced and upon treatment with propolis extracts all these effects were dose-dependently suppressed. Results show an immunomodulatory effect of propolis extracts which includes down-regulation of IDO activity. IDO enzyme is considered to play an important role in the development of immunodeficiency and neuropsychiatric symptoms in patient with chronic inflammation. The suppression of tryptophan degradation by propolis extracts may therefore be related with some of its beneficial health properties in humans. [Copyright &y& Elsevier]

Abstract: Aflatoxins (AFs), the secondary metabolites produced by species of Aspergilli, specifically Aspergillus flavus and Aspergillus parasiticus, have harmful effects on humans, animals, and crops that result in illnesses and economic losses. Wheat that is susceptible to these fungi infections through its growth, harvest, transport, and storage, is the most important staple food in Turkey. Therefore, this study has been undertaken to determine the AFB1, AFB2, AFG1, AFG2 levels by HPLC in forty-one wheat samples grown and consumed in some regions of Turkey. The concentrations of total AFs in the wheat samples were determined to be ranging from 10.4 to 643.5ng/kg. Fiftynine percent of the samples were found to be positive for total AFs. The percentage of positive samples for AFB1, AFB2, AFG1, and AFG2 were 42, 12, 37, and 12%, respectively. Although the detected levels are under the permitted levels for AFs in cereals, these amounts should be considered in regard to overall daily exposure to mycotoxins. [Copyright &y& Elsevier]

Abstract: Objective: Exposure to many xenobiotics may cause depletion of folic acid (folate), which is an essential vitamin for humans. Replacement of folate can be effective in protection against some diseases and in partial or total prevention of adverse effects related to xenobiotics. Aluminum (Al) is the most widely distributed metal in the outer crust of the earth. Its toxicity in humans is well known. However, there is no evidence that folate can decrease accumulation of Al to which humans can be exposed in many ways. The aim of the present study was to quantify organ Al accumulation and to evaluate whether there is any protective (or reductive) effect of folic acid on Al accumulation. Methods: Male Wistar rats were assigned oral Al chloride (200 mg·kg−1 ·d−1, n = 10, group 1) alone or in combination with folic acid (20 mg·kg−1 ·d−1, n = 10, group 2) for 8 wk. At the end of the period, bone, kidney, brain, and blood samples were collected, and Al concentrations were determined by electrothermal atomic absorption spectrophotometry. Results: Mean values of Al in the tissue samples from group 1 were higher than those from group 2 (all P < 0.05). No difference was observed in serum Al levels between groups (P > 0.05). Conclusion: These results suggest that folate supplementation might be useful to decrease Al accumulation in its main target organs, i.e., bone, kidney, and brain. [Copyright &y& Elsevier]

Metals are the oldest toxins known to human. Particularly, occupational and environmental exposure to aluminium, lead, mercury, cadmium, and manganese cause serious health problems by interaction with biological systems. Cellular targets of these metals are mostly specific biochemical processes (enzymes) and/or membranes of cells and organelles. To prevent and/or reduce the untoward or irreversible toxic effects of the metals by using biomarkers are as important as to know and to understand of their toxicity mechanisms. Dihydropteridine reductase (DHPR), which possessed essential thiol groups at the activite site, plays a crucial role in the maintenance of tetrahydrobiopterin (BH4). BH4 is the cofactor in the synthesis and regulation of neurotransmitters. A limited number of the evidences have shown that DHPR may be a target for the metals. Therefore, the present study was designed to assess possible in vitro effects of the commonly exposed metals on the enzyme activity. It was found that aluminium, cadmium, mercury, di-phenyl mercury, lead, diethyl lead, in chloride forms, and manganese, in sulphate form, led to statistically significant decreases in DHPR activity, in a concentration-dependent manner, in vitro. [Copyright &y& Elsevier]