Yalcin Atli

Intraperitoneal Alpha-Lipoic Acid to prevent neural damage after crush injury to the rat sciatic nerve

Objective Crush injury to the sciatic nerve causes oxidative stress. Alfa Lipoic acid (a-LA) is a neuroprotective metabolic antioxidant. This study was designed to investigate the antioxidant effects of pretreatment with a-LA on the crush injury of rat sciatic nerve. Methods Forty rats were randomized into four groups. Group I and Group II received saline (2 ml, intraperitoneally) and a-LA (100 mg/kg, 2 ml, intraperitoneally) in the groups III and IV at the 24 and 1 hour prior to the crush injury. In groups II, III and IV, the left sciatic nerve was exposed and compressed for 60 seconds with a jewelers forceps. In Group I (n = 10), the sciatic nerve was explored but not crushed. In all groups of rats, superoxide dismutase (SOD) and catalase (CAT) activities, as well as malondialdehyde (MDA) levels were measured in samples of sciatic nerve tissue. Results Compared to Group I, Group II had significantly decreased tissue SOD and CAT activities and elevated MDA levels indicating crush injury (p < 0.05). In the a-LA treatment groups (groups III and IV), tissue CAT and SOD activities were significantly increased and MDA levels significantly decreased at the first hour (p < 0.05) and on the 3rd day (p < 0.05). There was no significant difference between a-LA treatment groups (p > 0.05). Conclusion A-LA administered before crush injury of the sciatic nerve showed significant protective effects against crush injury by decreasing the oxidative stress. A-LA should be considered in the treatment of peripheral nerve injuries, but further studies are needed to explain the mechanism of its neuroprotective effects.

Effects of Intravenous Anesthetics on Renal Ischemia/Reperfusion Injury

Background. Renal ischemia/reperfusion (I/R)-induced tubular epithelial cell injury, called ischemic acute renal failure, is associated with high mortality in humans. Protecting the kidney against I/R injury is very important during complicated renal operations, transplantation surgery, and anesthesia. Aim. The purpose of this study was to investigate and compare the efficiency of ketamine, thiopental, propofol, etomidate, and intralipid in reducing the injury induced by free radicals in a rat model of renal I/R. Method. Forty-two Wistar rats were divided into seven groups in our study. Rats in the sham group underwent laparotomy and waited for 120 minutes (min) without ischemia. Rats in the control group were given nothing with ischemia-reperfusion. Rats in the I/R groups were given ketamine (20 mg/kg), thiopental (20 mg/kg) propofol (25 mg/kg), etomidate (10 mg/kg) and 10% intralipid (250 mg/kg) intraperitoneally 15 min prior to the ischemia for 60 min, followed by reperfusion for 60 min. The blood samples and kidney tissues of the rats were obtained under anesthesia at the end of the reperfusion period. Biochemical malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), blood urea nitrogen (BUN), creatine (Cr), aspartate aminotransferase (AST) were determined, and histopathological analysis was performed with these samples. Results. MDA level was increased significantly in the control group (p < 0.05). Histopathological findings of the control group confirmed that there was renal impairment by tubular cell swelling, interstitial edema, medullary congestion, and tubular dilatation. MDA levels were lower in the ketamine, thiopental, and propofol groups compared to the control group (p < 0.05). In the thiopental and propofol groups, the levels of histopathological scores were significantly lower than control and etomidate groups in ischemia-reperfusion. Conclusion. Our results demonstrated that I/R injury was significantly reduced in the presence of propofol and thiopental. The protective effects of these drugs may belong to their antioxidant properties. These results may indicate that propofol and thiopental anesthesia protects against functional, biochemical, and morphological damage better than control in renal I/R injury.

Serum reference levels of selenium, zinc and copper in healthy pregnant women at a prenatal screening program in southeastern mediterranean region of Turkey

PROJECT The aim of the study was to investigate the serum reference range for Selenium (Se), Zinc (Zn) and Copper (Cu) levels in women of 10-14 (group I) and 16-20 (group II) weeks of gestation and compare them with those in non-pregnant healthy women and healthy men. PROCEDURE This cross-sectional study was performed in 351 pregnant women [group I (n: 177) and group II (n: 174)], 30 non-pregnant women and 30 men as controls. The levels of Se, Zn and Cu levels were determined on flame and furnace atomic absorption spectrophotometer using Zeeman background correction. RESULTS In the 10-14 weeks of gestation Se, Zn and Cu serum levels were 44.85+/-9.23, 81.30+/-31.94 and 132.33+/-38.24 microg/dl, in 16-20 weeks of gestation were 47.18+/-10.92, 74.25+/-22.47 and 164.86+/-39.69 microg/dl, in non-pregnant women were 55.38+/-8.81, 121.41+/-29.22 and 104.75+/-39.14 microg/dl also in men 72.24+/-9.28, 134.85+/-15.95 and 78.29+/-20.90 microg/dl, respectively. CONCLUSION A significant low level of serum Se, Zn and a high level of Cu in the pregnant women in the 10-14 and 16-20 weeks of gestation were detected when compared with that of non-pregnant women and men.

Administration of honey to prevent peritoneal adhesions in a rat peritonitis model

AIM We investigated the effects of intraperitoneal honey on the development of postoperative intra-abdominal adhesions and oxidative stress in a model of bacterial peritonitis. METHODS Bacterial peritonitis was induced in 18 rats by cecal ligation and puncture. The rats were randomly assigned to three groups. Group 1 (n=6) received honey intraperitoneally, group 2 (n=6) received 5% dextrose intraperitoneally, and the third group received no fluid or medicine intraperitoneally one day after cecal ligation and puncture procedure. All animals were killed 14 days later so we could assess the adhesion score. Tissue antioxidant levels were measured in 1-g tissue samples taken from the abdominal wall. RESULTS Adhesion scores of honey treated group were significantly lower according to the control group (P<0.05) and statistically significant. Adhesion scores of honey were lower from 5% dextrose but not statistically significant (P>0.05). Malondialdehyde values of honey group were significantly lower from the control group (P<0.05) and levels in 5% dextrose group was higher than the honey group. Catalase levels were high in control and 5% dextrose groups. Superoxide dismutase levels were higher in the control group than the honey group (statistically significant). CONCLUSIONS Intraperitoneal honey decreased the formation of postoperative intra-abdominal adhesions without compromising wound healing in this bacterial peritonitis rat model. Honey also decreased the oxidative stress during peritonitis.

Re-Protective Effects of Pre- and Post-Laparoscopy Conditioning, Zinc, Pentoxifylline, and N-acetylcysteine in an Animal Model of Laparoscopy-Induced Ischemia/Reperfusion Injury of the Kidney

Background. Pneumoperitoneum (P) created to facilitate laparoscopy (L) is associated with splanchnic hypoperfusion, ischemia/reperfusion (I/R) injury, and oxidative stress. Aim. This study investigated the effects of pre- and post-laparoscopic conditioning, zinc, pentoxifylline (PTX), and N-acetylcysteine (NAC) on markers of I/R injury in an animal model. Methods. Sprague-Dawley male rats (n = 56, weight range 300–350 g) were randomly placed in one of seven treatment groups. Except for group C (control group who underwent a sham operation without pneumoperitoneum), pneumoperitoneum was created in all using CO2 insufflation under a pressure of 15 mmHg. Group L (laparoscopy) was subjected to 60 min of pneumoperitoneum. Group Lpre (laparoscopic preconditioning plus laparoscopy) was subjected to 5 min of insufflation and 5 min of desufflation followed by 60 min of pneumoperitoneum. Group Lpost (laparoscopy plus laparoscopic post-conditioning) was subjected to 60 min of pneumoperitoneum and 60 min of desufflation followed by 5 min of insufflation and 5 min of desufflation. The laparoscopy plus zinc (LZ), PTX (LP), and NAC (LNAC) groups received a single intraperitoneal injection of zinc (50 mg/kg), pentoxifylline (50 mg/kg), or N-acetylcysteine (150 mg/kg) 5 min before the desufflation period. Animals were sacrificed at the end of the experiments, and kidney samples were tested for malondialdehyde (MDA), catalase (CAT), glutathione peroxidase (GPX), and superoxide dismutase (SOD). Results. MDA levels, as an indicator of oxidative stress in kidney tissue samples, were significantly higher in all pneumoperitoneum groups compared to Group C, except for Group Lpre. The pattern of change in tissue levels of SOD, GPX, and catalase was variable in the different treatment groups. Conclusions. In this animal model of renal ischemia/reperfusion injury, laparoscopy caused renal ischemia as evidenced by elevated markers of tissue ischemia-reperfusion injury. This effect was significantly attenuated by post-laparoscopy conditioning, zinc, pentoxifylline, and N-acetylcysteine, but not by pre-laparoscopy conditioning.

Ischemia-Reperfusion Injury in Skeletal Muscle: Comparison of the Effects of Subanesthetic Doses of Ketamine, Propofol, and Etomidate

BACKGROUND Interest in the effects of anesthetics in skeletal ischemia-reperfusion injury (IRI) has recently emerged. Thus, the objective was to compare the effects of subanesthetic doses of ketamine, propofol, and etomidate in a skeletal IRI model. METHODS IRI was applied to rats by tourniquet method. Under thiopental anesthesia, five experimental groups were established as follows: (1) sham-control, (2) IRI, (3) IRI+Ketamine, (4) IRI+Propofol, and (5) IRI+Etomidate. Malondialdehyde, superoxide dismutase, catalase, and glutathione peroxidase were measured in skeletal muscle via a spectrophotometer. Zinc, iron, copper, and selenium were evaluated by atomic absorption spectrophotometer. RESULTS While the values of malondialdehyde and glutathione peroxidase were higher and lower, respectively, those of superoxide dismutase and catalase were identical in IRI group in comparison with sham-control. Zinc displayed a decrease in IRI group; however, no differences in iron and copper levels were determined. In rats treated with subanesthetic doses of ketamine, elevated malondialdehyde levels in IRI group were reversed to control levels by each dose. While each dose of ketamine decreased superoxide dismutase activities in comparison with IRI group, a reduction in catalase activity was only seen in 3mg/kg ketamine-treated rats. The attenuated glutathione peroxidase activity seen in IRI was greatly reversed by ketamine administration in all doses. No differences in zinc, copper, and iron levels were detected between IRI and ketamine-treated groups. Similar results were obtained either by the administration of propofol or etomidate. CONCLUSIONS Subanesthetic doses of ketamine, propofol and etomidate displayed beneficial effects in IRI.

Protective effects of zinc, pentoxifylline, and N-acetylcysteine in an animal model of laparoscopy-induced ischemia/reperfusion injury of the small intestine.

BACKGROUND Pneumoperitoneum induced to facilitate laparoscopy is associated with splanchnic hypoperfusion, ischemia/reperfusion (I/R) injury, and oxidative stress. AIM This study investigated the effects of pre- and postlaparoscopic conditioning, zinc, pentoxifylline, and N-acetylcysteine on markers of I/R injury of the small intestine in an animal model. METHODS Male Sprague-Dawley rats (n=56) were randomized to 1 of 7 treatment groups. Except for group 7 (control group that underwent sham surgery without pneumoperitoneum), pneumoperitoneum was induced in all by use of carbondioxide insufflation under a pressure of 15 mmHg. Group 1 (laparoscopic I/R) was subjected to 60 minutes of pneumoperitoneum. Group 2 (laparoscopic preconditioning plus laparoscopy) was subjected to 5 minutes of insufflation and 5 minutes of desufflation followed by 60 minutes of pneumoperitoneum. Group 3 (laparoscopy plus laparoscopic postconditioning) was subjected to 60 minutes of pneumoperitoneum and 60 minutes of desufflation followed by 5 minutes of insufflation and 5 minutes of desufflation. Group 4 (zinc), group 5 (pentoxifylline), and group 6 (N-acetylcysteine) received a single intraperitoneal injection of zinc (50 mg/kg), pentoxifylline (50 mg/kg), or N-acetylcysteine (150 mg/kg), respectively, 5 minutes before the desufflation period. Animals were killed at the end of the experiments, and small intestine samples were tested for malondialdehyde (MDA), catalase (CAT), glutathione peroxidase (GPX), and superoxide dismutase (SOD). RESULTS There was no significant difference for MDA levels between each other in the groups 1, 2, and 3. But MDA levels were higher significantly in groups 1, 2, and 3 than those of groups 4, 5, 6, and 7. SOD and GPX levels of group 3 were significantly higher than those of groups 1, 2, 4 through 7. According to the SOD levels, there was no significant difference between each other in those of groups 1, 2, 4 through 7. GPX levels of group 3 were significantly higher than those of groups 1, 2, 4 through 7. GPX levels of group 1 were significantly lower than those of groups 5 and 7. The mean CAT level of groups 1 and 2 was significantly lower than that of groups 3, 6, and 7. The mean CAT level of group 3 was significantly higher than that of groups 1, 2, 4 through 7. CONCLUSIONS In this animal model of small intestine I/R injury, laparoscopy caused small intestine ischemia as evidenced by elevated markers of tissue I/R injury. This effect was significantly attenuated by zinc, pentoxifylline, and N-acetylcysteine, but not by prelaparoscopy conditioning and postlaparoscopy conditioning.