Bülent Ergun

The effects of gender difference on monocrotaline-induced pulmonary hypertension in rats.

The present study aimed to compare the effect of gender difference on hemodynamic consequences in the development of monocrotaline (MCT)-induced pulmonary hypertension in rat. The effect of antioxidant enzyme systems on the development of pulmonary hypertension mediated by the phytotoxin MCT and the effect of gender on these antioxidant systems were also investigated. For this purpose, the right ventricular pressures (RVPs) and right ventricular/heart weight (HW) ratios were compared between groups and the glutathione (GSH) level and superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) activities were determined in lung and liver tissue samples of rats. RVP and right ventricular/HW ratios significantly increased in the MCT group compared to the control group. In the MCT group, RVP was significantly higher in males than females. MCT-induced pulmonary hypertension resulted in decreased GSH level, decreased GST and SOD activities and increased CAT activity in lung and liver tissues of both male and female rats. In addition, the lung and liver GSH level and GST and SOD levels were higher in female control rats compared to male control rats. The results of the present study, that antioxidant enzyme activities were different between the groups, highlight the possible role of oxidative stress in the pathogenesis of MCT-induced pulmonary hypertension in rats. Moreover, the lower antioxidant defense capacity of male rats than female rats may be considered as a cause of more aggressive course of MCT-induced pulmonary hypertension in males compared to females.

Oxidative stress-mediated myocardiotoxicity of ciprofloxacin and ofloxacin in juvenile rats.

In this study, evaluation of the myocardiotoxic effect potential of ciprofloxacin and ofloxacin in juvenile rats and the role of oxidative stress in heart toxicity was conducted. Doses (25 and 50 mg/kg) of each drug were administered to the rats for 1 week. Serum biochemical cardiotoxicity parameters and tissue malondialdehyde and nitric oxide levels were measured. All measured parameters were found elevated in the drug-treated rats, being the highest in the 50-mg/kg ofloxacin-treated rats. Ciprofloxacin and ofloxacin may cause myocardiotoxicity by inducing the oxidative stress in the heart, and nitric oxide is partly responsible for this toxicity.

Is N-acetyl cysteine protective against monocrotaline-induced toxicity?

Abstract Monocrotaline (MCT) is a pyrrolizidine alkaloid which induces cardio-pulmonary toxicity and hepatotoxicity in animals and humans. MCT is frequently ingested because of food grain contamination accidentally or in the form of herbal medicine preparations. The aim of this study was to observe the protective effect of N-acetyl cysteine (NAC) on MCT-induced pulmonary toxicity and hepatotoxicity. According to our results (right ventricular pressures [RVPs], ratios of right ventricle (RV)/heart weight (HW), plasma AST levels, liver glutathione levels, liver MDA levels and liver histopathological examinations of groups), protective effects were observed with NAC treatment in both MCT-induced pulmonary toxicity and hepatotoxicity.

Validated Reversed Phase HPLC Method for the Analysis of the Food Additive, Sodium Benzoate, in Soft Drinks and Jams

Abstract A rapid, simple, and sensitive method is described for the determination of the food preservative sodium benzoate in soft drinks, various jams, and ketchup. The method utilizes high performance liquid chromatography followed by diode array detection. Chromatographic separation was achieved using a C18 reversed phase column and methanol: water (70∶30, v/v) adjusted to pH 3.45 with glacial acetic acid as mobile phase, 0.45 mL . min−1 flow rate, and UV detection at 245 nm. Amoxicillin was used as the internal standard. The retention time observed for sodium benzoate and amoxicillin were 5.01 and 12.07 min, respectively. The method is selective, reliable, and reproducible with a relative standard deviation of 0.66 and linear in the range of 50–450 ng/mL sodium benzoate concentration. The limit of detection and limit of quantification concentrations were 61 pg/mL and 203 pg/mL, respectively. The proposed method can be used for the routine analysis of sodium benzoate in soft drinks and jams.

Matrix metalloproteinases are possible targets in monocrotaline-induced pulmonary hypertension: investigation of anti-remodeling effects of alagebrium and everolimus.

Objective: In our study, sildenafil alone and everolimus or alagebrium in combination with sildenafil were investigated in terms of their additional therapeutic and anti-remodeling activity in monocrotaline-induced pulmonary hypertension (PH) model in rats. In particular, the inter-relationships between PH and matrix metalloproteinases (MMPs) were investigated. Methods: The pulmonary artery responses of male Sprague Dawley rats were recorded using myography, and the quantities and activities of MMPs were analyzed in homogenates of the pulmonary arteries and lungs by enzyme-linked immunosorbent assays, activity assays, and gelatin zymography techniques. Results: Our results indicated that the therapeutic effects of sildenafil were accompanied by its suppressor effects on MMP activity. It was also shown that everolimus or alagebrium in combination with sildenafil showed additional regulatory effects on MMPs as well as functional responses on pulmonary artery pressure. Therefore, the enzymes in the MMP superfamily are likely to be target molecules for the treatment of PH. Conclusion: In conclusion, MMPs were involved in the pathogenesis of PH, and our results suggested that the addition of everolimus or alagebrium to sildenafil therapy may be beneficial in PH. Our results indicated that agents that limit pulmonary vascular hypertrophy and inflammation via their anti-remodeling effects significantly ameliorate mortality and morbidity in PH.

A GENERAL OVERVIEW OF OCHRATOXIN-A CONTENT OF COFEES SOLD IN LOCAL MARKETS WITH HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Okratoksin A (OTA), bazi Aspergillus ve Penicillium turleri tarafindan sentezlenen ozellikle islenmis tahillar, kahve cekirdekleri veya granul kahveler, sarap ve cesitli baharatlarda bulunabilen bir mikotoksindir. OTA insan ve hayvanlarda kanserojen, mutajenik ve teratojenik etkiler gostermektedir. Gerceklestirilen bu calismada yerel marketlerden temin edilen 30 adet kahve ornegi icerisindeki OTA miktari Yuksek Basincli Sivi Kromatografisi (YPSK) cihazi ile tayin edilmistir. Calismalar floresans dedektor kullanilarak Ex 330 Em 450 nm dalga boylarinda gerceklestirilmis, kolon sicakligi 25°C, sistem basinci 83 bar olarak olculmustur. Akis hizi 0.9 ml/dk olarak secilmistir. Kahveleri cozmek icin etanol kullanilmistir. Analiz boyunca C18 (200 mm 4.6 mm I.D., 5 µm partikul boyutuna sahip kolon kullanilmistir. OTA standardi ve numunelerin yaklasik 11.287 dk da sinyal verdigi gorulmektedir. Mobil faz olarak (su:asetonitril:asetik asit) (49.5:49.5:1) (h:h:h) kullanilmistir. Calisilan 30 adet ornegin tumunde cesitli miktarlarda OTA varligi tespit edilmis olup bunlardan sadece 12 tanesinin Turk Gida Kodeksi tarafindan belirlenen limitler altinda oldugu tespit edilmistir.