Aydın Ketani

Protective effects of coumarin and coumarin derivatives against carbon tetrachloride-induced acute hepatotoxicity in rats.

The comparison of the antioxidant activity of some coumarins with their molecular structure is well determined. However, the protective function of coumarins with various chemical structures against liver toxicity has not yet been well established. Therefore, the aim of this study was to evaluate the possible cytoprotective properties of coumarin and some coumarin derivatives against CCl(4) (carbon tetrachloride)-induced hepatotoxicity. Coumarin (1,2-benzopyrone) and coumarin derivatives esculetin (6,7-dihydroxycoumarin), scoparone (6,7-dimethoxycoumarin) and 4-methylumbelliferone (7-hyroxy-4-methyl) were examined for their protective effect against CCl(4)-induced hepatotoxicity in Male Sprague-Dawley rats. A single toxic dose of CCl(4) (1.25 ml kg(-1), orally) produced liver damage in rats, seen histologically as centrilobular necrosis. Administration of CCl(4) increased serum enzyme levels of aspartate transaminase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP). Pre-treatment of rats with esculetin (31.15 mg kg(-1), orally) and scoparone (35 mg kg(-1), orally) significantly prevented CCl(4)-induced increase in serum enzymes, whereas 4-methylumbelliferone (35 mg kg(-1)) and coumarin (30 mg kg(-1)) had no effect against CCl(4)-induced rise in serum enzymes. Morphological findings were consistent with the plasma transaminase observations. Among the coumarin analogs, esculetin, which possesses orthodihydroxy coumarins, showed the strongest protective effect against CCl(4)-induced liver damage, followed by scoparone, 4-methylumbelliferone and coumarin, respectively. The results of this study indicate that the chemical structures of coumarins play an important role in the prevention of liver toxicity.

Protective effect of Diyarbakır watermelon juice on carbon tetrachloride-induced toxicity in rats.

The present study was designed to evaluate the effect of Diyarbakır watermelon (Citrullus lanatus cv. Sürme) juice on lipid peroxidation states in rat liver, kidney and brain. In vivo administration of carbon tetrachloride (CCl(4)) once a week for 28 days caused a significant elevation of serum markers of liver damage, aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (TB) and decrease in albumin when compared to the control group. However, administration of carbon tetrachloride along with watermelon juice or ursodeoxycolic acid (UDCA) significantly reduces these changes. Increased lipid peroxide (LPO) level was observed in the liver, kidney and brain tissues after CCl(4) administration. However, watermelon juice and UDCA treatment prevented the increase in LPO. The results indicated that watermelon juice protects the liver, kidney and brain tissues from experimental CCl(4) toxicity in rats and that the protective effect of watermelon juice may be due to its antioxidant activity and inhibition of lipid peroxide formation. In conclusion, present study reveals biological evidence that supports the use of watermelon juice in the treatment of chemical-induced hepatotoxicity.

The effects of nitric oxide on the expression of cell adhesion molecules (ICAM-1, UEA-1, and tenascin) in rats with unilateral testicular torsion.

BACKGROUND/PURPOSE The aim of this study was to determine the effects of nitric oxide (NO) on the expression of adhesion molecules in the early course of testicular I-R injury in rats. METHODS Forty male Sprague-Dawley rats were separated into 4 groups, each containing 10 rats. A sham operation was performed in group 1 (control). In group 2 (I-R), after 6 hours of unilateral testicular torsion, 1-hour detorsion of the testis was performed. In group 3 (I-R/L-NAME), after performing the same surgical procedures as in group II, L-NAME was given for 30 minutes. In group 4 (I-R/Mol), after performing the same surgical procedure (torsion and detorsion) as in group II, molsidomine, an NO donor, was infused for 30 minutes. Then, ipsilateral orchiectomies were performed to measure the tissue levels of malondialdehyde (MDA) and NO and to make histologic examination. RESULTS MDA values and the testicular injury score decreased and NO values increased in the I-R/Mol-treated group compared with other experimental groups. The tenascin expression in the interstitial space and basement membrane of the tubuli seminiferi were milder in the I-R/Mol group compared with that of the I-R and the I-R/L-NAME. The acrosomes of the spermatids in I-R and I-R/L-NAME groups were stained mildly by lectin. In the I-R and I-R/L-NAME groups, the interstitial spaces, basement membrane of the tubuli seminiferi, and sertoli and germinal cells in testicular tissue were stained intensely by ICAM-1. CONCLUSIONS The expression of adhesion molecules such as tenascin, lectin, and ICAM-1 in the torted testicular tissue may be a pathophysiologic sign of inflammation. NO regulates adhesion molecules expression.

The effect of low-level laser therapy on the healing of hard palate mucosa and the oxidative stress status of rats

OBJECTIVE The biostimulation effects of low-level laser therapy (LLLT) have been demonstrated recently. This study investigated the effects of LLLT on palatal mucoperiosteal wound healing and oxidative stress status in rats. MATERIAL AND METHOD Forty-two male Wistar rats weighing 250-300 g were used in this study. A standardized full-thickness wound was created in the mucoperiosteum of the hard palates of the rats using a 3-mm-diameter biopsy punch. Treatment using a GaAlAs laser at a wavelength of 940 nm and a dose of 10 J/cm(2) was initiated after surgery and repeated on the 2nd, 4th, and 6th days post-surgery. Seven animals from each group were sacrificed on the 7th, 14th, and 21st days after surgery. Total antioxidant status and total oxidative status were measured in serum. RESULTS The histopathological findings revealed reduced numbers of inflammatory cells on the 7th day, increased mitotic activity of fibroblasts on the 14th and 21st day, and the same degree of collagen synthesis and vascularization on the days 7, 14, and 21 in the LLLT group compared with the control group. No significant differences in total oxidative status and total antioxidant status were observed between the groups. CONCLUSION LLLT using a GaAlAs laser at a wavelength of 940 nm and a dose of 10 J/cm(2) elicited a positive healing effect on palatal mucoperiosteal wounds likely via the induction of fibroblasts. The oxidative stress status was not affected by LLLT.

The effects of low-level laser therapy on palatal mucoperiosteal wound healing and oxidative stress status in experimental diabetic rats.

OBJECTIVE The biostimulation effects of low-level laser therapy (LLLT) have recently been demonstrated. In this study, we aimed to investigate the effects of LLLT on palatal mucoperiostal wound healing and oxidative stress status in experimental diabetic rats. MATERIALS AND METHODS Forty-two male Wistar rats that weighed 250-300 g were used in this study. Experimental diabetes was induced in all of the rats using streptozotocin. A standardized full thickness wound was made in the mucoperiosteum of the hard palates of the rats using a 3 mm biopsy punch. The rats were divided into groups: 1 (control group, non- irradiated), and 2 (experimental group, irradiated). Treatment using a GaAlAs laser at a wavelength of 940 nm and at dose of 10 J/cm(2) began after surgery, and was repeated on the 2nd, 4th, and 6th days post-surgery. Seven animals from each group were killed on the 7th, 14th, and 21st day after surgery. Biopsies were performed for the histological analysis and blood samples were collected by cardiac puncture for biochemical analysis. RESULTS The histopathological findings revealed reduced numbers of inflammatory cells, and increased mitotic activity of fibroblasts, collagen synthesis, and vascularization in rats in group 2. The total oxidative status was significantly decreased in the laser-treated group on the 21st day. CONCLUSIONS LLLT elicits a positive healing effect on palatal mucoperiostal wounds, and modulates the oxidative status in experimental diabetic rats.

The protective role of pomegranate juice against carbon tetrachloride-induced oxidative stress in rats

Most pomegranate (Punica granatum Linn., Punicaceae) fruit parts are known to possess enormous antioxidant activity. The present study was carried out to determine the phenolic and flavonoid contents of Derik pomegranate juice and determine its effect against carbon tetrachloride (CCl4)-induced toxicity in rats. Animals were divided into four groups (n = 6): group I: control, group II: CCl4 (1 ml/kg), group III: CCl4 + pomegranate juice and group IV: CCl4 + ursodeoxycholic acid (UDCA). Treatment duration was 4 weeks, and the dose of CCl4 was administered once a week to groups II, III and IV during the experimental period. CCl4-treated rats caused a significant increase in serum enzyme levels, such as aspartate aminotransferase, alanine aminotransferase and total bilirubin, and decrease in albumin, when compared with control. Administration of CCl4 along with pomegranate juice or UDCA significantly reduces these changes. Analysis of lipid peroxide (LPO) levels by thiobarbutiric acid reaction showed a significant increase in liver, kidney and brain tissues of CCl4-treated rats. However, both pomegranate juice and UDCA prevented the increase in LPO level. Histopathological reports also revealed that there is a regenerative activity in the liver and kidney cells. Derik pomegranate juice showed to be hepatoprotective against CCl4-induced hepatic injury. In conclusion, present study reveals a biological evidence that supports the use of pomegranate juice in the treatment of chemical-induced hepatotoxicity.

Effects of specific inhibition of cyclooxygenease-2 on kidney in bilateral adrenalectomized rats

In the kidney, prostaglandins represent important physiological modulators of renal hemodynamics and salt and water homeostasis. In this experimental study of bilaterally adrenalectomized (ADX) rats, we aimed to investigate whether the administration of selective (celecoxib) inhibitor of COX-2 would alter the morphological and functional changes in rat kidney tissue. Twenty-one male Sprague–Dawley rats weighing 225–250 g were used. The animals were divided into three groups. Group 1 rats (Sham-control, n = 7) did not receive any treatment. In group 2 rats (ADX/Untreated, n = 7), bilateral ADX was performed via a single dorsal incision. In group 3 (ADX/COX-2) rats, the same operation was performed as described for group 2 and then the COX-2 inhibitor celecoxib was administered by gavage for a period of 7 days. On the 7th day of the study, renal function was assessed by measurements of blood urea nitrogen (BUN) and serum creatinine levels. Biopsies were obtained from the remaining left kidneys before killing the rats. There was no significant difference in the BUN and creatinine values between the groups. In ADX/Untreated group, capillary congestion in glomerule, inflammation, hemorrhage and congestion in intertubular area, and cytoplasmic vacuolation in renal tubules was observed. Mild damage was observed in the ADX/COX-2 group. The number of macrophages was significantly decreased in ADX/COX-2 group when compared to ADX/Untreated group (P < 0.0001). Our study indicates that celecoxib may be an important factor affecting renal morphological changes after the bilaterally ADX.