Gözde Girgin

Exposure of newborns to aflatoxin M1 and B1 from mothers' breast milk in Ankara, Turkey

Aflatoxins (AFs) are important risks for human health due to their widespread presence in foods and environment. However, contamination risk of breast milk with different pollutants including AFs is high in todays life conditions. Since breast milk is a major nutrient for infants, feeding of infants with safe milk is essential. Therefore, the objective of this study was to determine the levels of AF M(1) and B(1) in breast milk samples collected from 75 mothers in Ankara, Turkey. AF M(1) and B(1) levels were investigated by high performance liquid chromatography (HPLC) with a fluorescence detector following an extraction procedure. The limit of detection was found to be 5 ng/l. Both AFs were detected in diverse degrees in all breast milk samples: The level of AF M(1) were in the ranges of 60.90-299.99 ng/l, and AF B(1) were in the ranges of 94.50-4123.80 ng/l. These results pointed out the exposure of mothers and neonates to AF M(1) and B(1), and the necessity of further research on mycotoxin contamination both in foods and biological fluids as well as protection strategies.

Preventive effect of aminoguanidine compared to vitamin E and C on cisplatin-induced nephrotoxicity in rats.

In this study, the antioxidant effect of aminoguanidine on nephrotoxicity of a single dose of cisplatin is investigated and compared with the effects of well-known antioxidants vitamin C and E combination. Tubular damage and perivascular inflammation were observed in kidney samples of the cisplatin-administered groups. Aminoguanidine and vitamin C-E combination are found to be capable of preventing these effects of cisplatin. Liver tissues of all groups were intact. Cisplatin-induced oxidative stress was evidenced by significant decrease in glutathione and significant increase in malondialdehyde levels in kidney samples. Antioxidants with cisplatin decreased malondialdehyde levels. Antioxidants with cisplatin prevented the decrease in liver glutathione levels. The nephrotoxicity was confirmed biochemically by significant elevation of serum urea and creatinine levels. Both vitamin C-E combination and aminoguanidine prevented the increase in serum urea levels according to the cisplatin group.

Neopterin as a prognostic biomarker in intensive care unit patients

PURPOSE The present study was undertaken to evaluate urinary neopterin in intensive care unit patients. MATERIALS AND METHODS Urinary neopterin levels were determined in systemic inflammatory response syndrome (n = 10), sepsis (n = 18), septic shock (n = 9), and multiple organ dysfunction syndrome (n = 5). It was tested whether neopterin is a differential parameter among the patient groups. Furthermore, the results were also evaluated by comparing with a healthy control group (n = 30), and the relationship between neopterin and mortality or Acute Physiology and Chronic Health Evaluation II scores were investigated. RESULTS Neopterin levels of the control group and patients were detected as 111 +/- 11 and 3850 +/- 1081 mumol/mol creatinine, respectively (P < .05). It was significantly increased in the sepsis and septic shock groups compared to the systemic inflammatory response syndrome group (P < .05). Neopterin levels were significantly higher in the patients with mortality and lower Acute Physiology and Chronic Health Evaluation II scores. CONCLUSION This study showed that monitoring of urinary neopterin profile can be used in intensive care units to show the degree and prognosis of the disease.

Immunomodulatory effects of Turkish propolis: changes in neopterin release and tryptophan degradation.

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-alpha) and interferon-gamma (IFN-gamma) 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.

Neopterin, Catalase and Superoxide Dismutase in Females with Benign and Malignant Breast Tumors

Abstract The aim of the present study was to evaluate the relationship between the levels of neopterin among patients with benign and malignant breast disease and the relation with the stage of the malignant process. In this study, neopterin concentrations and enzyme activities of superoxide dismutase (SOD) and catalase (CAT) were determined in malign (n=30) and benign breast tumor patients (n=30) by high performance liquid chromatographic and spectrophotometric methods, respectively. Results were compared with a healthy control group (n=20). The correlations between neopterin, CAT and SOD were also evaluated in controls and patients. Urinary neopterin level of the control group was (mean value ± S.D.) 128.6 ± 64.6 μmol/mol creatinine. Neopterin concentrations in patients with breast malignancy were 153.6 ± 71.2 μmol/mol creatinine and 107.8 ± 32.1 μmol/mol creatinine in benign disorders patients. The mean neopterin level in the benign group was found to be statistically different from the malign tumor group (p = 0.039). SOD and CAT activities in controls were found as 3.57 ± 0.84 U/mg protein and 2.19 ± 0.20 U/mg protein, respectively. In patients with malignancy, the SOD activity was 3.84 ± 0.73 U/mg protein while CAT activity was 1.03 ± 0.13 U/mg protein. Patients with benign breast disorders, SOD activity was 4.09 ± 1.00 U/mg protein and CAT activity was 1.02 ± 0.18 U/mg protein. Whereas SOD activity did not differ between the groups of patients and controls, the mean catalase level in the control group was higher than in the benign and malign tumor groups (both p <0.001). Urinary neopterin concentration seems to be an important and useful biomarker in diagnosis of breast tumors in clinical practice.

Immune system modulation in patients with malignant and benign breast disorders: tryptophan degradation and serum neopterin

Tryptophan degradation metabolites are known to suppress T-cell function, which is a mechanism of resistance of tumor cells against immune surveillance. The aim of this study was to evaluate tryptophan degradation along with serum neopterin levels in benign and malignant breast disease. Serum tryptophan and kynurenine levels and neopterin concentrations of 30 patients with malignant and 27 patients with benign breast disease were determined by HPLC and ELISA, respectively. The slight increase in tryptophan degradation in a subgroup of cancer patients with higher grade tumors was not statistically significant, but the increased degradation was correlated with higher neopterin concentrations. Neopterin levels in patients with malignant breast disease were significantly higher than in the benign group (p<0.05). Tryptophan degradation positively correlates with the aggressiveness of the tumor because it changes with tumor grade rather than disease stage.

Immunomodulation and Oxidative Stress in Denim Sandblasting Workers: Changes Caused by Silica Exposure

Abstract Workers in denim sandblasting are at a high risk of developing silicosis, an occupational lung disease caused by inhaling crystalline silica dust. The development and progress of silicosis is associated with the activation of the immune system and oxidative stress. In the former, interferon-gamma induces both neopterin release and the enzyme indoleamine [2, 3]-dioxygenase (IDO) in various cells. The determination of the kynurenine-to-tryptophan ratio and neopterin concentration has proven to be an efficient method to monitor the activation status of IDO and cellular immunity. The present study aimed to investigate whether occupational silica exposure leads to any alterations in neopterin levels, tryptophan degradation, and activities of superoxide dismutase (SOD) and catalase (CAT), agents in the antioxidant defense system. Fifty-five male denim sandblasting workers and twenty-two healthy men as controls were included. Mean neopterin and kynurenine levels, kynurenine-to-tryptophan ratio, and SOD activity were higher in subjects with silicosis compared to non-exposed controls (all, p<0.05). Neopterin levels and kynurenine-totryptophan ratios were positively correlated (p<0.05); however, no correlation was observed between length of employment and the measured parameters. Some of the measured parameters were significantly affected by the severity of the pathology. Our results suggest that silica exposure activates the cellular immune response. The increased neopterin levels and tryptophan degradation confirm the possibility of their use as an indicator of cellular immune response. Sažetak IMUNOMODULACIJA I OKSIDATIVNI STRES U RADNIKA U PJESKARENJU TRAPER PLATNA: PROMJENE UZROKOVANE IZLOŽENOSTI SILICI Radnici u pjeskarenju traper platna izloženi su visokom riziku od silikoze, profesionalne plućne bolesti uzrokovane udisanjem čestica silikatne prašine. Razvoj i progresija silikoze povezani su s aktivacijom imunosnog sustava i oksidativnim stresom. Pri aktivaciji imunosnoga sustava, interferon-gama potiče otpuštanje neopterina i enzima indoleamina [2, 3]-dioksigenaze (IDO) u različitim vrstama stanica. Određivanje omjera kinurenina i triptofana te koncentracije neopterina pokazale su se učinkovitim metodama praćenja aktivacijskoga statusa IDO-a i staničnog imuniteta. Ovaj rad istražuje uzrokuje li profesionalna izloženost silici promjene u razinama neopterina, degradaciji triptofana i aktivnosti superoksid dismutaze (SOD) i katalaze (CAT), agenata u antioksidativnom obrambenom sustavu. U istraživanju je sudjelovalo 55 muških radnika u pjeskarenju traper platna i 22 zdrava muškarca u kontrolnoj skupini. Srednje vrijednosti razina neopterina i kinurenina, omjera kinurenina i triptofana, te aktivnosti SOD-a bile su više u radnika oboljelih od silikoze nego u kontrolnoj skupini (p<0,05). Razina neopterina i omjer kinurenina i triptofana bile su u pozitivnoj korelaciji (p<0,05). Međutim, korelacija nije uočena između mjerenih vrijednosti i radnog staža. Neke od mjerenih vrijednosti bitno su ovisile o težini patologije. Dobiveni rezultati daju naslutiti da izloženost silici uzrokuje aktivaciju staničnog imunosnog odgovora. Povećane razine neopterina i degradacije triptofana potvrđuju mogućnost njihova korištenja kao pokazatelja staničnog imunosnog odgovora.

Evaluation of Changes in Immune System of Operating Room Personnel by Measurement of Urinary Neopterin Concentrations

Abstract Today it is known that neopterin is mainly produced by activated macrophages and a marker of immune activation and macrophage activity. Increased neopterin concentrations are observed in diseases related to cellular immunity including occupational pathologies. The major goal of the present study was to evaluate the possible alteration of neopterin levels in operating room personnel, and also to show whether screening of neopterin may be useful to monitor the effect of occupational anesthetic exposure on the cellular immune system. Therefore, urinary neopterin to creatinine levels in both, exposed workers (n = 40) and healthy volunteers (n = 30), were measured by using high-performance liquid chromatography. At the same time, the correlation among urinary neopterin levels and working years, age, and smoking status were evaluated. Compared to controls, urinary neopterin levels in the exposed group were increased (controls: 85 ± 16 μmol/mol creatinine, workers: 151 ± 39 μmol/mol creatinine; p <0.05). The findings suggest that the follow up of neopterin levels may have diagnostic value in possible occupational exposure-related immune system disorders. Moreover, its biological monitoring should be performed in workplaces for clinical diagnosis and prognosis.

Is neopterin level a predictive and differential biomarker in patients with thyroid disorders

Neopterin production provides information about the extent of cellular immune activation. Measurement of neopterin levels may also provide predictive and prognostic information in patients with malignant thyroid diseases. In the present study, neopterin levels were investigated in patients with thyroid disorders (no.=68). Twenty-four patients had papillary thyroid cancers and the rest of them benign thyroid disorders. Results were compared with a healthy control group (no.=30). It was observed that there was a significant difference in neopterin levels between the control group and the thyroid disorders group (p<0.05). The mean neopterin levels in malignant and benign patients were also significantly different (p<0.05). Monitoring of urinary neopterin profile may be used in early diagnosis of papillary thyroid cancer. Neopterin seems to be a differential biomarker for malignant and benign thyroid disorders.

Neopterin Release and Tryptophan Degradation in Patients with Uveitis.

ABSTRACT Purpose: Uveitis is an intraocular inflammation affecting the highly vascularized uveal tissue. Early recognition and appropriate therapeutic intervention of uveitis are important since the condition may be associated with systemic disease and untreated uveitis may lead to blindness. Neopterin, an unconjugated pteridine, is an important biomarker of cell-mediated immunity and has a potential function in the process of inflammation. In addition to neopterin release, cellular immune activation also induces indoleamine 2,3-dioxygenase (IDO). In this study, the aim was to investigate possible immune changes in uveitis by determination of neopterin concentrations and tryptophan (Trp) degradation. Materials and Methods: The participants who attended to the ophthalmology clinic with uveitis were divided into two groups: active (n = 63) and remission (n = 41). Additionally 30 healthy subjects were recruited as a control group. Results: In total, in 104 uveitis patients, urinary and serum neopterin, kynurenine (Kyn), and Kyn/Trp were found to be statistically higher than the 30 controls (all, p < 0.05). It was observed that all of the measured parameters did not differ between active and remission uveitis groups (all, p > 0.05), except for the Kyn/Trp ratio (p < 0.05). Urinary and serum neopterin levels were positively correlated with Kyn/Trp in the uveitis patients (both p < 0.05). Conclusions: From these results, it can be concluded that uveitis can cause alterations in neopterin levels and the Kyn pathway. It seems that the measured parameters can be useful markers of cellular immune response in uveitis, although they might not be used to differentiate active or remission uveitis.