The Effect of Boric Acid and Sodium Pentaborate Pentahydrate-Treated Foreskin Derived Mesenchymal Stem Cells on Liver Fibrosis.

Liver fibrosis is a worldwide public health problem due to its life-threatening complications, including portal hypertension, liver failure, cirrhosis, and hepatocellular carcinoma (HCC). Liver fibrosis is the net result of a complex excessive accumulation of extracellular matrix (ECM). Activation of hepatic stellate cells (HSCs) are the cause of deposition of ECM and are commonly recognized as a key step in liver fibrosis. The aim of this study was to investigate the effect of foreskin-derived mesenchymal stem cells treated with boron compounds on liver fibrosis. Rats were injected intraperitoneally with thioacetamide (TAA) at a dose of 150 mg/kg except sham and control groups' rats. Thioacetamide (TAA), foreskin-derived mesenchymal stem cells (TAA + FSDMSC), FSDMSC treated with boric acid (TAA + FSDMSC + BA), FSDMSC treated with sodium pentaborate pentahydrate (TAA + FSDMSC + NaB), control and sham groups were studied. Boron compound treated foreskin-derived mesenchymal stem cells were injected into the tail vein, and evaluations were conducted after 4 weeks and liver tissues were obtained for structural, immunohistochemical, and western blot studies and blood samples were taken for biochemical analysis. FSDMSC (BA) alleviates TAA-induced rats liver fibrosis, and BA showed a positive effect on foreskin-derived mesenchymal stem cells viability. After using BA-treated mesenchymal stem cells, we observed that there was regression in the fibrotic areas at TAA-induced liver fibrosis. The result demonstrates that the contribution of TAA + FSDMSC and TAA + FSDMSC (NaB) at the level of structure is not effective in regression of fibrosis in TAA-generated liver fibrosis. We concluded that FSDMSC treated with BA may be a factor in the regression of fibrosis.

Effects of bone marrow-derived mesenchymal stem cells on doxorubicin-induced liver injury in rats.

Doxorubicin (DOX) is a potent chemotherapeutic agent and has toxic effects on various organs, including the liver. In the current study, we aimed to investigate the effects of bone-marrow-derived mesenchymal stem cell (BM-MSC) administration on DOX-induced hepatotoxicity in rats. 24 Wistar-albino rats were divided into three groups: Control, DOX, and DOX+MSC. DOX (20 mg/kg) was administered to the DOX group. In the DOX + MSC group, BM-MSCs (2 × 106 ) were given through the tail vein following DOX administration. DOX administration led to significant structural liver injury. Besides this, oxidative balance in the liver was impaired following DOX administration. DOX administration also led to an increase in apoptotic cell death in the liver. Structural and oxidative changes were significantly alleviated with the administration of BM-MSCs. Furthermore, BM-MSC administration suppressed excessive apoptotic cell death. Our findings revealed that BM-MSC administration may alleviate DOX-induced liver injury via improving the oxidative status and limiting apoptotic cell death in the liver tissue.

First Molecular Characterisation of Blastocystis from Experimental Rats in Turkey and Comparison of the Frequencies Between Obese and Non-obese Groups

Objective: Blastocystis is a zoonotic protozoan that infects a wide range of animals, including humans and rodents. This study aimed to determine the frequency and subtype distribution of Blastocystis in laboratory rats at a laboratory animal facility in Turkey. Methods: This study included 54 male Sprague-Dawley rats from Aydin Adnan Menderes University Laboratory Animal Center. Among these rats, 30 were fed with high-fat diet (obese group) and the remaining 24 received standard chow (non-obese group). Blastocystis positivity was determined with amplification of small subunit 18S rRNA gene following their nucleic acid extraction from faecal samples. Subtypes were detected by submitting the partial 18S rRNA gene sequences to the database (pubmlst. Results: Blastocystis infection was detected in 33 (61.1%) of 54 laboratory rats. The frequency of Blastocystis was significantly different between obese and non-obese rats (p<0.05), with 43.3% and 83.3%, respectively. When referred to the database, exact matches were identified with Blastocystis subtype 4 (ST4) for all isolates. In the phylogenetic analysis of the partial 18S rDNA sequence, the sequence was closely clustered with reference ST4 subtypes from other countries, including China, Japan, United Kingdom and Czech Republic. Conclusion: This study revealed the high rate of Blastocystis colonisation in laboratory rats, posing a risk for human transmission. The comparison of obese and non-obese groups supported the idea that Blastocystis might be an indicator of healthy gut flora. The detection of ST4 in all rats agreed with previous reports of the predominance of this subtype in rodents.

Investigation of the embryotoxic and teratogenic effect of Hypericum perforatum in pregnant rats.

OBJECTIVE: Hypericum perforatum (HP) is a herbal product used in the treatment of depression, but its harm on the fetus has not been established. This study investigated the effects of HP according to fetal clinical, morphologic, and histologic findings. Study design is an animal study. MATERIALS AND METHODS: Fifty-four 4-5-month-old female Wistar rats were divided into three groups: control, 100 mg/kg HP, and 300 mg/kg HP. HP treatment using drinking water was started one week before mating and ended with the delivery of pups. RESULTS: HP exposure before conception diminished the pregnancy rate and decreased the fetal number; during pregnancy it tended to increase the duration of gestation, and deteriorated the fetal development as determined using body weight. It also damaged liver and kidney tissues, most probably due to oxidative stress, as supported through inducible nitric oxide synthase antibody staining findings at both doses. CONCLUSION: HP should not be recommended to women who would like to be pregnant or are pregnant because it can be harmful for both fetal and maternal health.

The efficacy of single-dose 5-fluorouracil therapy in experimental caustic esophageal burn.

INTRODUCTION: Accidental ingestion of caustic substances may cause serious problems in children. Approximately 20% of caustic ingestions result in esophageal stricture formation, resulting from excessive collagen synthesis to the extracellular matrix by fibroblasts. Recent studies showed that a single application of 5-fluorouracil (5-FU) is a very effective inhibitor of fibroblast proliferation and differentiation for prolonged periods. Using an experimental model, we investigated the efficacy of single-dose 5-FU on stricture formation after caustic esophageal burn. MATERIALS AND METHODS: Forty Wistar-Albino rats were divided randomly into 4 equal groups: group 1 (sham-operated group), the esophagus was uninjured and untreated; group 2 (control group), the esophagus was injured and left untreated; group 3 (intraperitoneal treatment group), the esophagus was injured and treated immediately after the burn injury with a single intraperitoneal dose (20 mg/kg) of 5-FU; group 4 (local treatment group), the esophagus was injured and treated immediately after the burn injury with a single intraesophageal application of 5-FU at a concentration of 25 mg/mL. Caustic esophageal burn was produced by instilling 10% NaOH in the distal esophagus. The distal esophagi were harvested at 28 days postoperatively. Histologic sections were assessed by measuring the stenosis index (SI) and histopathologic damage score. Hydroxyproline (HP) levels in the tissues were determined biochemically. RESULTS: There were significant reductions in the SI (P < .05), histopathologic damage score (P < .05), and HP level (P < .05) in the intraperitoneal treatment group when compared with the control group. No significant differences in the SI and histopathologic damage score were detected between the control and local treatment groups (P > .05), whereas significant reduction in the HP level was determined between these groups (P < .05). CONCLUSION: A single intraperitoneal dose of 5-FU had a preventive effect on stricture formation after caustic esophageal burn. This observation suggests that 5-FU may prevent this undesirable complication in the clinical setting. Clinical studies are now required to verify this form of treatment. Local intraesophageal application of 5-FU immediately after the burn injury was not effective. Further investigations are required to determine the appropriate timing of application of 5-FU at the local site of injury.

Growth failure, tardive dyskinesia, megacolon development, and hepatic damage in neonatal rats following exposure to trimethobenzamide in utero.

OBJECTIVE: Trimethobenzamide (TMB) has a pregnancy category C labeling. Tardive dyskinesia and gastrointestinal involvement in neonates were not described earlier. We aimed to investigate neurological, developmental, and hepatic effects of TMB. METHODS: Ten 10 pregnant rats were divided into two groups. During pregnancy, Group I (control) were injected with saline; Group II with TMB (5 mg/kg/day). After delivery, two experiments were planned: experiment 1 (neuro) and Experiment 2 (hepatic). Control groups contained offsprings delivered from Group I mothers: Group I-offsp-neuro (n = 15) and Group I-offsp-hepatic (n = 15). Thirty offsprings delivered from Group II mothers formed Group II-offsp-neuro (n = 15) and Group II-offsp-hepatic (n = 15). Neuro group offsprings were followed-up to observe neurological symptoms and assessed for normal growth. Hepatic group livers were excised for histological evaluation. RESULTS: The body weight between neuro groups showed significant differences (p < 0.05). In Group II-offsp-neuro low body weight, poor hair growth, tardive dyskinesia and megacolon were observed. Some alterations of liver histology were noticed in Group II-offsp-hepatic (p < 0.001). CONCLUSIONS: In utero TMB exposure may cause growth retardation, neurological damage in the developing brain and intestine, and hepatic damage. Despite recent publications reporting safety of TMB, we suggest that obstetricians and pediatricians should make a good risk-benefit assessment before prescribing TMB.

Effect of tenoxicam on rat liver tissue.

BACKGROUND/AIMS: Tenoxicam is a non-steroidal antiinflammatory drug, which has antipyretic and antiinflammatory effects. Though it is known that the major side effect of non-steroidal antiinflammatory drugs is on the gastrointestinal tract and liver, there have been few studies regarding the effects of tenoxicam. In this study, we aimed to investigate whether tenoxicam has a deleterious effect on liver tissue using immunohistochemical staining and biochemical analysis. METHODS: A total of 30 male Wistar albino rats were included in this study. Animals were equally and randomly divided into three groups as follows: Group I (Controls), Group II (Injection with 10 mg/kg/day of tenoxicam) and Group III (Injection with 20 mg/kg/day of tenoxicam). At the end of the study, some liver tissue samples were taken and kept in neutral formalin for histological and immunohistochemical evaluation. Liver tissue samples were embedded in paraffin blocks after routine tissue preparation procedures, and were stained with hematoxylin-eosin and immunohistochemical stain. Liver samples taken for biochemical analysis were washed with physiological saline. Thiobarbituric acid reactive substances and superoxide dismutase activity were measured in the obtained supernatants. RESULTS: There were significant structural changes in liver tissues of the tenoxicam-administered groups when compared with the controls. We observed that hepatic (inducible nitric oxide synthase) receptors were increased in the study groups. Furthermore, hepatic superoxide dismutase and malondialdehyde levels were prominently higher in the tenoxicam-administered groups when compared to levels of the control group. CONCLUSIONS: Nitric oxide may exert an antioxidative effect against lipid peroxidation to one point at low levels; however, it may also have the opposite effect at higher levels in tenoxicam induced liver injury.

Tenoxicam modulates antioxidant redox system and lipid peroxidation in rat brain.

We investigated effects of two doses of Tenoxicam, a type 2 cyclooxygenase inhibitor, administration on lipid peroxidation and antioxidant redox system in cortex of the brain in rats. Twenty-two male Wistar rats were randomly divided into three groups. First group was used as control. 10 and 20 mg/kg body weight Tenoxicam were intramuscularly administrated to rats constituting the second and third groups for 10 days, respectively. Both dose of Tenoxicam administration resulted in significant increase in the glutathione peroxidase activity, reduced glutathione and vitamins C and E of cortex of the brain. The lipid peroxidation levels in the cortex of the brain were significantly decreased by the administration. Vitamin A and beta-carotene concentration was not affected by the administration. There was no statistical difference in all values between 10 and 20 mg Tenoxicam administrated groups. In conclusion, treatment of brain with 10 and 20 mg Tenoxicam has protective effects on the oxidative stress by inhibiting free radical and supporting antioxidant redox system.

The effects of allopurinol on rat liver and spleen tissues in a chronic hyperammonemia animal model.

OBJECTIVE: To investigate whether hyperammonemia can lead to any structural change in liver and spleen tissues or biochemical changes in blood and if allopurinol (ALLO) has a protective effect in hyperammonemia. METHODS: This study was conducted between April and May 2006. Thirty-six females Wistar Albino rats were randomly divided into 3 equal groups: Controls, administered with ammonia (NH3) and administered with NH3 + ALLO groups. Ammonium acetate (2.5 mmole/kg/day) was injected to NH3 group intraperitoneally (IP) for 28 days. The other group received ammonium acetate (2.5 mmole/kg) plus ALLO (50 mg/kg) IP for 28 days. After finishing the study, blood and tissue samples were collected to perform histopathological and biochemical analysis. RESULTS: Liver and spleen tissues were normal in the control group. In NH3 group, liver tissues were minimally vacuolar and granular degenerations and moderate mononuclear cell infiltration. However, there was no histopathological change in NH3 + ALLO group. Spleen tissues were normal in NH3 group. In biochemical analysis, there was no significant difference between the groups (p>0.05). CONCLUSION: The ammonium acetate may cause minimal structural changes in rat liver and ALLO can prevent this. We found that biochemical parameters do not necessarily correlate with the histopathological findings.

Effect of prenatal exposure to diclofenac sodium on Purkinje cell numbers in rat cerebellum: a stereological study.

Diclofenac sodium (DS) is commonly used as a non-steroidal anti-inflammatory drug. Although several adverse effects are clearly established, it is still unknown whether prenatal exposure to DS has an effect on the development of the cerebellum. In this study, we investigated the total number of Purkinje cells of the cerebellum in a control group and in a DS-treated group of male rats using a stereological method. The DS in a dose of 1 mg/kg daily was intraperitoneally injected to the drug-treated group of pregnant rats beginning from the 5th day after mating for a period of 15 days during pregnancy. Physiological serum at 1 ml dose was intraperitoneally injected to the control group of pregnant rats at the same period. After delivery, male offspring were obtained and each main group was divided into two subgroups that were 4-week-old (4W-old) and 20-week-old (20W-old). Our results showed that the total number of Purkinje cells in offspring of drug-treated rats was significantly lower than in the offspring of control animals. These results suggest that the Purkinje cells of a developing cerebellum may be affected by administration of DS during the prenatal period.

Effect of prenatal exposure to an anti-inflammatory drug on neuron number in cornu ammonis and dentate gyrus of the rat hippocampus: a stereological study.

Prenatal exposed to an anti-inflammatory drug is a major problem for the developing central nervous system. It is not well known the effect of prenatal exposed to a non-steroidal anti-inflammatory drug on the hippocampus. Total neuron number in one side of the cornu ammonis (CA) and gyrus dentatus (GD) of the hippocampal formation in control and drug-treated (diclofenac sodium, DS) groups of male rats was estimated using the optical fractionator technique. Each main group has also two subgroups that are 4 weeks old (4W-old) and 20 weeks old (20W-old). In CA, no significant difference between 4W-old DS-treated and their control was found, but a significant difference was observed between 20W-old DS-treated and their controls. A decreasing of neuron number was 12% for 20W-old DS-treated group. In GD, a decreasing of the granule cell number in 4W-old of DS-treated group was seen but an increasing of granule cell number was found in the 20W-old drug-treated rats in comparison to its control group, 7% and 9%, respectively. Although an increasing of neuron number in CA at the control group was seen with age, from 4th week to 20th week (10%), age-dependent substantial granule cell decline (17%) was observed in GD. No age effect on the total cell numbers of CA and GD of the drug-treated groups was seen in comparison to 4W-old week and 20W-old. A pronounced neuron loss observed in the drug-treated group may be attributed to the neurotoxicity of diclofenac sodium (DS) on the developing hippocampal formation. Age-dependent neuron increase in the CA of 20W-old and neuron decline in GD of 20W-old control groups may be a result of a dual effect of saline injection during the fetal life, since these animals were exposed to a stress of 15-day-period of saline injection, prenatal stress. The reason of no age effect on CA and GD cell number in the drug-treated groups may be attributed to the depletion of the progenitor cells due to neurotoxicity of DS in the fetal life of these animals.

Effect of lisinopril on rat liver tissues in L-NAME induced hypertension model.

N(G)-Nitro-L-arginine methyl ester hydrochloride (L-NAME) is a non-specific nitric oxide (NO) inhibitor and it has been used to eliminate the role of NO in many studies like animal models for hypertension. In this study, we aimed to investigate whether lisinopril treatment has any biochemical and/or histopathological effect on rat liver tissue in a L-NAME-induced hypertension model. Forty-eight 6-weeks-old male Spraque-Dawley rats were used in the study. The animals used in the study were randomly divided into four equal groups. To induce hypertension, L-NAME was added to drinking water at a concentration of 600 mg/l and each rat was given 75 mg/kg/day of L-NAME for 6 weeks. Tail cuff systolic blood pressure (SBP) was measured at first, third, and sixth weeks. There was a significant difference between the experiment groups and controls. In only lisinopril given and L-NAME plus lisinopril administered groups, each rat was given 10 mg/kg of lisinopril for 6 weeks. At the end of the study, the animals were sacrificed. Blood and tissue samples were collected for biochemical and histopathological analysis. It has been observed that mean NO level was significantly decreased in L-NAME given group (p<0.05). Mean ALT levels were significantly increased in lisinopril and L-NAME plus lisinopril given groups, when compared with the control group (p<0.05). AST levels were in normal range in all groups (p>0.05). Hepatocyte degeneration was prominent in lisinopril given group, whereas mononuclear cell infiltration was significant in L-NAME given groups. Although the beneficial effects in L-NAME-induced hypertension treatment, lisinopril can lead to some unexpected results like hepatocyte degeneration, serum enzyme level elevation, and slight mononuclear cell infiltration.

Caffeic acid phenethyl ester prevents cadmium-induced cardiac impairment in rat.

Caffeic acid phenethyl ester (CAPE), a flavonoid like compound, is one of the major components of honeybee propolis. It was found to be a potent free radical scavenger and antioxidant recently. The aim of this study was to examine the effect of CAPE on cadmium (Cd)-induced hypertension and cardiomyopathy in rats. In particular, nitric oxide (NO) may contribute to the pathophysiology of Cd induced cardiac impairment. Malondialdehyde (MDA, an index of lipid peroxidation) levels and nitric oxide (NO, a vasodilator) levels were used as markers Cd-induced cardiac impairment and the success of CAPE treatment. Also, the findings have been supported by the histopathologic evidences. The rats were randomly divided into three experimental groups each (12), as follows: the control group, Cd-treated group (Cd) and Cd plus CAPE-treated group (Cd+CAPE). CdCl(2) in 0.9% NaCl was administrated intraperitoneally (i.p.) with a dose of 1mg/kg/day. CAPE was co-administered i.p. a dose of 10 microM/kg for 15 days. Hypertension was found to be induced by intraperitoneal administration of Cd in a dose of 1mg/kg/day on the measurements taken 15 days later. MDA levels were increased (p<0.001) in cardiac tissue and NO levels were decreased (p<0.05) in serum in the Cd group than those of the control group had. On the other hand, there was a slight difference (increase) in MDA levels in the Cd+CAPE group than the ones in the control group (p<0.003). In addition, MDA levels were decreased and NO levels were increased in the Cd+CAPE group compared with the Cd group (p<0.001, p<0.0001, respectively). As a result, treatment with CAPE significantly reversed the increased lipid peroxidation (LPO) product, MDA, and decreased NO levels in Cd treated animals. In the histopathologic examination, a significant hypertrophy in atrial and ventricular myofibrils was observed in only Cd administered group, in comparison with the control group. There was no statistically significant difference between the CAPE given and control groups by means of atrial and ventricular myofibril diameters. In conclusion, the underlying mechanism of the myocardial hypertrophy may be related to hypertension due to inhibition of NO production in the vessels, and CAPE has a protective effect on Cd-induced hypertension mediated cardiac impairment in the rats.

Evaluation of the effects of cadmium on rat liver.

Cadmium is one of the most toxic pollutants in environment. Cadmium accumulation in blood affects the renal cortex and causes renal failure. In this study, we aimed to evaluate the effects of cadmium on rat liver tissue. Eighteen male albino rats aged ten weeks old were used in the study. 15 ppm of cadmium was administered to rats via consumption water daily. At the end of the 30th study day, the animals were killed under ether anesthesia. After the liver tissue samples were taken, histopathological and biochemical examinations were performed. Histopathologic changes have included vacuolar and granular degenerations in hepatocytes, heterochromatic nucleuses and sinusoidal and portal widenings. Central vein diameters were normal in cadmium exposed group. Whereas, there was statistically significant difference between two groups by means of sinusoidal (p< 0.001) and portal triad diameters (p< 0.01). Malondialdehyde (MDA) is an indicator of lipid peroxidation. In this study, MDA was used as a marker of oxidative stress-induced liver impairment in cadmium exposed rats. Superoxide dismutase (SOD) and catalase (CAT) activities were also measured to evaluate the changes in antioxidative system in liver tissues. Current findings showed that MDA levels were increased and SOD and CAT activities were decreased in cadmium exposed group compared to control group. The difference between two groups was statistically significant (pvalues: MDA,p< 0.01; CAT,p< 0.01 and SOD,p< 0.05). In conclusion, these findings suggest the role of oxidative mechanisms in cadmium-induced liver tissue damage.

Biological and morphological effects on the reproductive organ of rats after exposure to electromagnetic field.

OBJECTIVE: The biological effect of electromagnetic field (EMF) emitted from mobile phones is a current debate and still a controversial issue. Therefore, little is known on the possible adverse effects on reproduction as mobile phone bio-effects are only a very recent concern. The aim of this experimental study was to determine the biological and morphological effects of 900 MHz radiofrequency (RF) EMF on rat testes. METHODS: The study was performed in the Physiology and Histology Research Laboratories of Süleyman Demirel University, Faculty of Medicine, Isparta, Turkey in May 2004. Twenty adult male Sprague-Dawley rats weighing 270-320 gm were randomized into 2 groups of 10 animals: Group I (control group) was not exposed to EMF and Group II (EMF group) was exposed to 30 minutes per day, 5 days a week for 4 weeks to 900 MHz EMF. Testes tissues were submitted for histologic and morphologic examination. Testicular biopsy score count and the percentage of interstitial tissue to the entire testicular tissue were registered. Serum testosterone, plasma luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels were assayed biochemically. RESULTS: The weight of testes, testicular biopsy score count and the percentage of interstitial tissue to the entire testicular tissue were not significantly different in EMF group compared to the control group. However, the diameter of the seminiferous tubules and the mean height of the germinal epithelium were significantly decreased in EMF group (p<0.05). There was a significant decrease in serum total testosterone level in EMF group (p<0.05). Therefore, there was an insignificant decrease in plasma LH and FSH levels in EMF group compared to the control group (p>0.05). CONCLUSION: The biological and morphological effects resulting from 900 MHz RF EMF exposure lends no support to suggestions of adverse effect on spermatogenesis, and on germinal epithelium. Therefore, testicular morphologic alterations may possibly be due to hormonal changes.

Investigation on the histopathological effects of thyroidectomy on the seminiferous tubules of immature and adult rats.

INTRODUCTION: This study aimed to investigate the histopathological effects of thyroidectomy on both immature and adult rat testes. MATERIALS AND METHODS: Male albino Wistar rats, 4 weeks old and weighing between 45 and 55 g, were used for this study. The experimental groups were as follows: 2-week control group (group I); 2-week thyroidectomy group (group II); 4-week control group (group III); 4-week thyroidectomy group (group IV); 6-week control group (group V), and 6-week thyroidectomy group (group VI). The control groups included both sham-operated and untreated rats. In groups II, IV and VI, total thyroidectomy was performed under ether anesthesia in all rats at 4 weeks of age. The rats were killed in the 2nd, 4th and 6th weeks, respectively, following the thyroidectomy. The testes of each animal were evaluated histologically. RESULTS: In group II, spermatogenesis progressed to meiosis but round spermatids were found to be decreased and pachytene spermatocytes were observed to be increased when compared to group I. Giant pachytene spermatocytes were seen. There were also many degenerated cells of intermediate origin in the seminiferous epithelium. In groups IV and VI, spermatogonia and primary spermatocytes were normal in appearance, but there was widespread degeneration of the other spermatogenic cells. In addition, some closed lumina covered by degenerated and dead cells were observed. In group II, the mean outer diameter, luminal diameter and area occupied by seminiferous epithelium decreased by 19.74, 32.18, and 28.12%, respectively. In group IV, these data decreased by 23.9, 16.52, and 48.5%, respectively, and in group VI, by 21.10, 19.76 and 40.29%, respectively, when compared with the control groups. These data were statistically significant (p < 0.001). CONCLUSIONS: Thyroid hormones could have a marked influence on the seminiferous tubules of both immature and adult rats, and their permanent lack results in a depression in seminiferous tubule growth as shown by the reduced outer and luminal diameters and area occupied by the seminiferous epithelium, which could give rise to degenerative changes in the spermatogenic cells of thyroidectomized rats. In addition, all these changes could also result from both the inability of Sertoli cells to support spermatogenic cells and the diminished levels of GH and FSH.

Protective role of melatonin and a combination of vitamin C and vitamin E on lung toxicity induced by chlorpyrifos-ethyl in rats.

The ameliorating effects of melatonin and vitamin C plus vitamin E were examined histologically and biochemically in lung tissues in rats exposed to chlorpyriphos-ethyl (CE). Experimental groups were as follows: Control group (C), CE treated group (CE), vitamin C plus vitamin E treated group (Vit), melatonin treated group (Mel), vitamin C plus vitamin E plus CE treated group (Vit + CE), and melatonin plus CE treated group (Mel + CE). Vitamin E and vitamin C were administered intramuscularly at the rates of 150 and 200 mg per kg body weight, respectively, in Vit and Vit + CE groups, once a day for 6 consecutive days. Melatonin was administered intramuscularly at the rate of 10 mg per kg body weight in Mel and Mel + CE groups, once a day for 6 consecutive days. At the end of the fifth day, the rats of CE, Vit + CE and Mel + CE groups were treated orally with CE dissolved in corn oil with two equal doses of 41 mg CE per kg body weight at zero and twenty-first hours. Tissue samples of lungs were taken by using appropriate techniques for biochemical and histological examinations under anesthesia at the twenty-fourth hours of CE administration, at the end of the sixth day of the experiment. In tissue homogenates, the level of thiobarbituric acid reactive substances (TBARS), antioxidant potential (AOP), and the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were determined. TBARS was significantly high (p < 0.05) in CE group compared to control group, while TBARS was found to significantly decrease (p < 0.05) with Vit and Mel groups compared to control. On the other hand, TBARS was seen to significantly decrease (p < 0.05) in both groups of Vit + CE and Mel + CE compared to CE group. In comparison with CE group, SOD activity was significantly high (p < 0.05) with the groups of Vit, Mel, Vit + CE and Mel + CE. GSH-Px activity was found to significantly decrease (p < 0.05) with CE group, compared with both C and Vit groups. AOP was significantly lower (p < 0.01) in CE group than C group. Although there was an increased AOP with Vit + CE and Mel + CE groups compared to CE group, the increase in AOP was only seen to be significant (p < 0.05) in Mel + CE group. In comparison with C group, AOP significantly (p < 0.05) increased with Vit group. There was also a significant (p < 0.05) increase in AOP with Mel + CE group, compared with CE group. Additionally, AOP was significantly lower (p < 0.05) in Vit + CE group than Mel + CE group. Lungs were examined histologically at the end of sixth day. There were remarkable changes in the histomorphology of peribronchial and perivascular area in the lung of rats treated with CE. These were infiltration of mononuclear cells (such as lymphocytes, plasmocytes, macrophages), hyperplasia of type II pneumocyte, and thickened and increased connective tissue. Damage to the lung tissue such as increased inflammatory mononuclear cells in peribronchial and perivascular areas were more pronounced for the CE group than Vit + CE and Mel + CE groups in which these changes were higher than C, Vit and Mel groups. These results suggest that CE increases lipid peroxidation and decreases antioxidant enzymes activities and AOP due to increasing oxidative stress induced by CE, and high doses of vitamin C plus vitamin E and melatonin considerably reduce CE toxicity in lung tissues of rats.

The effect of melatonin on morphological changes in liver induced by magnetic field exposure in rats.

In this study, we aimed to investigate the possible effect of melatonin on morphological changes in liver induced by magnetic fields exposure. Thirty albino young male Wistar Albino rats were used in the study. They were divided into 3 groups. Control group (C) (n: 10) received daily intraperitoneal injections of saline (0.1 ml/100 g) containing 5% ethanol for two weeks. Only magnetic field exposed (MF) group (n: 10); only magnetic field exposed had daily intraperitoneal injections of physiologic saline (0.1 ml/100 g) containing 5% ethanol for two weeks. Magnetic field exposed and melatonin treated (MF+m) group (n: 10); melatonin was dissolved in ethanol with further dilution in physiological saline. The animals in this group were exposed magnetic fields for two weeks. The magnetic fields exposed animals had intraperitoneal single dose of 4 mg/kg melatonin (0.1 ml/100 g) at 10:00 o'clock daily for two weeks following magnetic fields exposure. We used commercial CB handheld portable transceiver, Midland (USA) labelled, of 4 Watts, 40 channel. This channel frequency has been measured 27.17 MHz with frequency counter. According to the IRPA exposure standards; for 27 MHz, for 6 min, exposure limit is 0.2 mW/cm2. This value is for General Public. For occupational exposure limit is 1 mW/cm2. We have to consider General Public exposure limit. Therefore our limit is 0.2 mW/cm2. In other words; in this study; our exposure is always over the recommended limit. All the animals were decapitated. Liver samples were fixed in buffered neutral formalin. Paraffin sections were dyed with hematoxylen-eosin. Sections were examined under light microscopy. In MF group; sinusoidal dilatations, mixed cell infiltrations noticed in the periportal area, necrosis and vacuoler degeneration were determined in liver samples. However, parenchymal and stromal structures were observed to be prevented partially from effects of magnetic fields in melatonin treated group. In conclusion, it is suggested that melatonin has a mild preventive effect on magnetic field exposed changes in liver tissue in the rats.