Fatih Ekici

Caffeic acid phenethyl ester protects rabbit brains against permanent focal ischemia by antioxidant action: A biochemical and planimetric study

The present study was conducted to investigate whether caffeic acid phenethyl ester (CAPE), an active component of propolis extract, has a protective effect on brain injury after focal permanent cerebral ischemia, and to determine the possible antioxidant mechanisms. Cerebral infarction in adult male New Zealand rabbits was induced by microsurgical procedures producing right focal permanent middle cerebral artery occlusion (pMCAO). CAPE was administered to the treatment group after pMCAO at a dose of 10 micromol kg(-1) once a day intraperitoneally for 7 days. Neurological deficits were evaluated, using a modified six-point scale. Spectrophotometric assay was used to determine the contents of malondialdehyde (MDA), glutathione (GSH), catalase (CAT), nitric oxide (NO) and xanthine oxidase (XO). In the ipsilateral hemisphere, the infarct volume of the brain was assessed in brain slices stained with heamatoxylen and eosin. The results showed that treatment with CAPE significantly reduced the percentage of infarction in the ipsilateral hemisphere compared with the ischemia group. CAPE treatment significantly attenuated the elevation of plasma MDA, CAT and XO content (p<0.05), whereas it significantly increased the levels of plasma GSH and NO (p<0.05). Therefore, subacute CAPE administration plays a protective role in focal pMCAO due to attenuation of lipid peroxidation and its antioxidant activity. All of these findings suggest that CAPE provides neuroprotection against cerebral ischemia injury through its antioxidant action.

Inhibitory effect of pinealectomy on the development of cerebellar granule cells in the chick: A stereological study

Melatonin has some effects upon morphological features of various structures in small animals and human being. However, there has been no investigation concerning its physiological role on development of cerebellar granule cells. In this study, the changes induced by pinealectomy procedure on cerebellar development and their granule cell numbers in the chick were investigated using quantitative stereological methods. A total of 15 Hybro Broiler newly hatched chicks were randomly divided into three equal groups: pinealectomy group (n=5) and non-pinealectomized control group (n=5) and sham-operated group (n=5). Pinealectomy procedure and sham operation were done in 3-day-old chicks and all animals were sacrificed for histopathological evaluation and subsequent stereological analysis in the 8th week. Here, it was observed that pinealectomy significantly reduces the granular cell number in cerebellar cortex of the chicks (P<0.001). The present study is the first stereological study to evaluate the histomorphological effects of pinealectomy on the cerebellar granule cells of the chick. We suggest that the granule cell loss in the cerebellar cortex is due to developmental retardation in early postnatal period, although its exact mechanism is not clear. Based on our findings, we intimate that pineal gland/melatonin might play an important role in the development of cerebellar granule cells in the chick.

Acute cardiotoxic effects of high dose toluene: an experimental study

OBJECTIVE This study aimed to investigate the acute cardiotoxic effects of high dose toluene and its damage mechanisms on heart tissue in the acute period. METHODS Twenty adult male Wistar Albino rats (200-220 g) were used in this controlled experimental animal study. Animals were divided into two equal groups: a control group (Group 1) and a high dose (6 mL/kg/gavage) toluene-administered group (Group 2). Arterial blood pressure (BP) and heart rate (HR) values were measured at 30th, 60th and 90th minutes after toluene was administered. At the end of the experimental period, blood samples and heart tissues were taken from the rats. Serum troponin T levels were assayed. Heart tissue sections were stained using routine histological methods and examined under a light microscope. In addition, the sections were immunohistochemically stained using the avidin-biotin-peroxidase method to determine caspase-3 immunoreactivity and TUNEL to detect apoptosis. To compare the apoptotic index, the Mann-Whitney U test was used. For comparisons between the two groups, the independent t- test was used. In addition, time-based changes of intra-group parameters were evaluated using paired t tests. RESULTS BP and HR values were low in toluene-treated rats compared to the control group. Troponin T levels were increased in toluene-administered animals as compared with controls [Toluene group: 0.140 (0.010-2.000) ng/mL vs control group: 0.010 (0.010-0.010) ng/mL, p=0.01]. Histopathologic examination of heart tissue sections showed congestion and edema in toluene administrated rats. Higher TUNEL positivity and (+++) immunoreactivity for caspase-3 protein were observed in the toluene group compared to the control group. CONCLUSION The present study demonstrated that high doses of toluene cause apoptosis and may lead to impairment of cardiac function in the acute period.