The histopathological and electrophysiological effects of thymoquinone and methylprednisolone in a rabbit traumatic facial nerve paralysis model.

OBJECTIVE: We aimed to determine the effects of methylprednisolone and thymoquinone on nerve healing in a traumatic facial nerve paralysis animal model. SUBJECTS AND METHODS: Twenty-four rabbits were randomly divided into 4 groups: group I: control group received no medication and no trauma; group II: sham group received no medication after facial nerve trauma group III: 5mg/kg/day thymoquinone administered; group IV: 1mg/kg/day methylprednisolone administered. An initial electrophysiological assessment was performed in all the animals. The buccal branch of the facial nerve was then clipped to form a traumatic facial paralysis model. The drugs were administered for two weeks once a day. At the end of the second month, the electrophysiological assessments were performed and the distal part of the traumatic facial nerve were dissected and examined under light microscopy. RESULTS: Best nerve regeneration was observed in the control and the thymoquinone groups, respectively, whereas the weakest regeneration was determined in the sham group. Thymoquinone and methylprednisolone significantly increased nerve recovery, as measured by histopathological scores and electrophysiological assessment. In the thymoquinone group, due to postoperative amplitude, axon diameter and thickness of myelin sheath values were significantly further increased nerve regeneration compared to that of the methylprednisolone group and these values were close to those of the values of the control group. CONCLUSION: Thymoquinone was slightly better than methylprednisolone for functional nerve recovery. The neuroprotective effect of thymoquinone was attributed to its antioxidant and anti-inflammatory effects. Thymoquinone can have a new treatment option to ameliorate the nerve injury.

Comparison of Histopathological Effects of Thymoquinone and Local Nasal Corticosteroids in Allergic Rhinitis in a Rabbit Model.

BACKGROUND/AIMS: In this study, we aimed to evaluate the histopathological effects of thymoquinone treatment of the nasal mucosa in a rabbit model of allergic rhinitis, and we compared its effects with those of nasal mometasone furoate. METHODS: A total of 24 male New Zealand rabbits were used. The animals were randomly assigned to one of four groups. Group 1 received no treatment, while group 2 underwent ovalbumin (OVA) sensitization only. Group 3 was the study group; after OVA sensitization, the rabbits were treated with intranasal thymoquinone. The group 4 rabbits received mometasone furoate for 7 days after OVA sensitization. Mucosal structures were stained with hematoxylin and eosin, while toluidine blue was used to stain mast cells. Apoptosis was evaluated using a TUNEL assay. RESULTS: In the positive control groups, including the thymoquinone and intranasal mometasone furoate groups, intraepithelial and submucosal inflammation and goblet cell hypertrophy were significantly decreased compared to group 2 (p < 0.001). The cilial structure was normal, as was the chondrocyte structure in both treatment groups. CONCLUSION: This is the first study to evaluate the histopathological effects of thymoquinone in an allergic rhinitis model. Thymoquinone reduced allergic inflammation and may be valuable for treating allergic rhinitis. However, additional studies are needed.

Comparison of microporous polysaccharide hemospheres and Ankaferd Blood Stopper in a rabbit epistaxis model.

The aim of this study was to evaluate the histopathological impact, effectiveness, and safety of two hemostatic agents, Ankaferd Blood Stopper (ABS) and microporous polysaccharide hemospheres (MPH), in an experimental rabbit epistaxis model. Rabbits were randomly assigned, using a computerized random number generator, to the following three groups of six animals: group 1 (control, irrigated with saline); group 2 (ABS-treated); and group 3 (MPH-treated). In all groups, a standardized rabbit epistaxis model was used. Hemostasis time and extent of nasal bleeding were measured to compare the hemostatic effect of ABS and MPH among groups. Septums were removed for histopathological analysis, 7 days after the procedure. ABS reduced hemostasis time to 104.2 s and amount of bleeding to 20.5 mg. MPH reduced hemostasis time to 71.7 s and amount of bleeding to 11.5 mg. Mean bleeding time in wounds administered ABS and MPH was significantly shorter compared with wounds administered isotonic saline solution (p = 0.004). ABS and MPH application decreased bleeding significantly compared with the control group (p = 0.004). Bleeding time and amount in the MPH group was significantly reduced compared with the ABS group (p = 0.013 and p = 0.004, respectively). There was no significant difference in the histopathological evaluation results between the ABS, MPH, and control groups. Our data indicate that both ABS and MPH represent safe, effective, and fast-acting hemostatic agents in the management of epistaxis. MPH was more effective than ABS in terms of hemostasis time and amount of bleeding.

Histopathological effects of intranasal phototherapy and nasal corticosteroids in allergic rhinitis in a rabbit model.

Allergic rhinitis is one of the most common health problems and has a major effect on quality of life. Although new-generation antihistamines and nasal steroids are the main treatment options, complete resolution cannot be obtained in some patients. Besides common side effects such as nasal irritation and epistaxis, the use of these drugs is controversial in some patients, such as pregnant or breastfeeding women. These findings highlight the need for new treatment options. Although phototherapy has been successfully used in the treatment of atopic dermatitis, which is an IgE-mediated disease and shares several common pathogenic features with allergic rhinitis, there are limited studies about its role in the treatment of allergic rhinitis. In this study, we aimed to evaluate and compare the histopathological effects of intranasal phototherapy (Rhinolight) and nasal corticosteroid treatment on the nasal mucosa in allergic rhinitis in a rabbit model and we found that both treatment options significantly reduced inflammation in the nasal mucosa without increasing apoptosis of mucosal cells.

Methylene blue attenuates renal ischemia-reperfusion injury in rats.

BACKGROUND AND PURPOSE: In our study, we investigated the effects of methylene blue (MB) on histopathological changes in renal ischemia/reperfusion (I/R) injury rat model. MATERIAL AND METHODS: Twenty-one Sprague-Dawley male rats were divided equally into three groups. Group 1 (control) was administered intraperitoneal saline solution. In Groups 2 (untreated group) and 3 (MB treatment), the renal arteries were clamped, and ischemia (for 1 hour) and then reperfusion (for 4 hours) were applied. Thirty minutes before ischemia, the untreated group received physiological saline, whereas the treatment group was administered 30 mg/kg MB through an intraperitoneal route. Blood samples were drawn, and renal specimens were harvested 5.5 hours after physiologic saline injection in the control and immediately after the reperfusion period in the other groups. The levels of tissue superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), total oxidant status (TOS), total antioxidant status (TAS), plasma urea, creatinine and ischemia modified albumin (IMA) were measured. Moreover, the histopathological damage score of the renal tissue was determined. RESULTS: MB significantly alleviated the severity of histopathological damage by increasing the levels of tissue SOD and TAS and decreasing TOS concentrations in the renal I/R model (p<0.05). CONCLUSION: Administration of MB in renal I/R damage may play a protective role.

The effect of ß receptor blockade through propranolol on corneal neovascularization.

PURPOSE: To evaluate the inhibitory effects of propranolol, a nonselective and lipophilic ß-adrenergic receptor blocker, on alkali-induced corneal neovascularization (NV). METHODS: Corneal NV was induced in 24 eyes of 24 Wistar rats using NaOH. Following alkali burn, animals were randomized into 4 groups according to topical treatment. Group I received 0.9% NaCl, Group II received preservative-free dexamethasone sodium phosphate 1 mg/mL, Group III received propranolol hydrochloride 1 mg/mL, and Group IV received 0.5 mg/mL propranolol hydrochloride drops twice a day for 7 days. The inhibitory effects of the drugs were compared as the percent areas of cornea covered by NV. Anti-vascular endothelial growth factor (VEGF) and anti-active caspase-3 immunostainings were also performed in corneal sections. RESULTS: The median percent area of corneal NV was 59% (40.3-65.6) in Group I, 25.5% (20.9-43.4) in Group II, 68.9% (36.7-78.0) in Group III, and 50.4% (42.2-63.3) in Group IV. Group III and IV did not show any difference in comparison to Group I. Group II showed a statistically significant smaller area of corneal NV compared with Group I, III, and IV (P=0.004 for each comparison). Anti-VEGF immunostaining was significantly less in Group II compared with the other groups. Anti-active caspase-3 immunostaining was not different among the treatment groups. CONCLUSIONS: Topical propranolol 1 or 0.5 mg/mL does not have a significant inhibitory effect on alkali-induced corneal NV in rats.

Protective effects of rosmarinic acid against renal ischaemia/reperfusion injury in rats.

OBJECTIVE: To investigate the potential protective effects of Rosmarinic acid (RA) on rats exposed to ischaemia/reperfusion renal injury. METHODS: The prospective study was conducted at Abant Izzet Baysal University, Turkey, and comprised 21 male Spraque Dawley rats weighing 250-270g each. They were divided into three equal groups. Unilaterally nephrectomised rats were subjected to 60 minutes of left renal ischaemia followed by 60 minutes of reperfusion. Group 1 had sham-operated animals; group 2 had ischaemia/reperfusion untreated animals; and group 3 had ischaemia/reperfusion animals treated with rosmarinic acid. Serum creatinine, blood urea nitrogen, tissue malondialdehyde, glutathione peroxidase, superoxide dismutase and myeloperoxidase (MPO) activities, and light microscopic findings were evaluated. SPSS 17 was used for statistical analysis. RESULTS: Treatment of rats with rosmarinic acid produced a reduction in the serum levels of creatinine and blood urea nitrogen compared to the other groups. However, no statistically significant difference was found. The levels of malondialdehyde and myeloperoxidase were decreased in the renal tissue of group 3, while glutathione peroxidose and superoxide dismutase levels remained unchanged. The injury score decreased in the treatment group rats compared to the untreated group. Rosmarinic acid significantly decreased focal glomerular necrosis, dilatation of Bowman's capsule, degeneration of tubular epithelium, necrosis in tubular epithelium, and tubular dilatation. CONCLUSIONS: Rosmarinic acid prevented ischaemia/reperfusion injury in the kidneys by decreasing oxidative stress.

Interleukin 10 reduces testicular damage in experimental testicular ischemia/reperfusion injury.

OBJECTIVE: To evaluate the protective effect of interleukin 10 (IL-10) on biochemical and histopathologic changes in experimental testicular ischemia or reperfusion injury (RI) in rats. METHODS: Sprague-Dawley rats were randomly divided into 3 groups, each containing 7 rats; sham-control, I-R/untreated group, and I/R treated with IL-10. The ischemia period was 6 hours, and orchiectomy was performed after 1 hour of detorsion. IL-10 was given intraperitoneally in a period of 10 minutes before reperfusion. In all groups, ipsilateral orchiectomies were performed to make histologic examination and biochemical analysis such as malondialdehyde, glutathione peroxidase, and myeloperoxidase (MPO). RESULTS: IL-10 treatment significantly decreased the I-R-induced elevation in testes malondialdehyde levels. In the I-R/IL-10-treated group, testes glutathione peroxidase levels were increased compared with the I-R/untreated group rats. MPO activities were significantly increased in the testes tissues of the I-R/untreated group. However, in the I-R/IL-10-treated group, MPO levels significantly decreased. Histopathologically, in the I-R/untreated group rats, edema, congestion, hemorrhage among seminiferous tubules, and necrosis of the germinal cells were predominant features in sections. The testicular injury score was lower in the IL-10-treated group rats compared with the I-R/untreated group. CONCLUSION: IL-10 might play a protective role in reducing reperfusion injury.

Protective effects of montelukast and Hypericum perforatum against intestinal ischemia-reperfusion injury in hamsters.

AIM: To evaluate the effects of montelukast and Hypericum perforatum against ischemia/reperfusion (I/R)-induced intestinal damage. MATERIALS AND METHODS: Twenty-eight hamsters were divided into 4 groups following midline abdominal laparotomy: control group (n = 7), I/R group (n = 7), montelukast and I/R (MIR) group (n = 7), and Hypericum perforatum and I/R (HPIR) group (n = 7). After 60 min of ischemia through obstruction of the superior mesenteric artery, 24 h of reperfusion was maintained. Ten minutes prior to the reperfusion period, the MIR group received 7 mg/kg of intraperitoneal montelukast and the HPIR group received 7 mg/kg of intraperitoneal Hypericum perforatum. Malondialdehyde, glutathione, myeloperoxidase, and cardiotrophin-1 levels were measured from blood samples. A semiquantitative histological evaluation was performed. RESULTS: Montelukast and Hypericum perforatum significantly reduced malondialdehyde levels and increased glutathione levels compared to the I/R group (P < 0.008). A statistically significant difference was also found between the I/R group and MIR and HPIR groups in terms of myelqperoxidase levels (P < 0.008). The MIR and HPIR groups showed increased cardiotrophin- 1 levels compared to the control and I/R groups (P < 0.008 for all). The MIR and HPIR groups showed significantly lower histological scores compared to the I/R group (P = 0.03 and P = 0.007, respectively). CONCLUSION: This study demonstrated the preventive effects of montelukast and Hypericum perforatum on I/R-induced intestinal injury.

Inhibitory effects of topical cyclosporine A 0.05% on immune-mediated corneal neovascularization in rabbits.

BACKGROUND: We aimed to study the inhibitory effects of topical cyclosporine A (CsA) 0.05% on immune-mediated corneal neovascularization, and to compare its efficacy with those of dexamethasone 0.1% and bevacizumab 0.5%. METHODS: Immune-mediated corneal neovascularization was created in 36 right eyes of 36 rabbits. The rabbits were then randomized into four groups. Group I received CsA 0.05%, Group II received dexamethasone 0.1%, Group III received bevacizumab 0.5%, and Group IV received isotonic saline twice a day for 14 days. The corneal surface covered with neovascular vessels was measured on the photographs. The rabbits were then sacrificed and the corneas excised. Paraffin-embedded sections were stained with hematoxylin-eosin and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay. RESULTS: The means of percent area of corneal neovascularization in Group I, II, III, and IV were 24.4%, 5.9%, 37.1%, and 44.1%, respectively. The inhibitory effect of CsA 0.05% was found to be better than the effect found in the bevacizumab 0.5% and control groups (p = 0.03 and p = 0.02, respectively). CsA 0.05% was found to have significantly lesser inhibitory effects on corneal neovascularization than dexamethasone 0.1% (p < 0.001). Apoptotic cell density was higher in Group III and Group IV than in Group I and Group II. There was no difference between Group I and Group II in terms of apoptotic cell density (p = 0.7). CONCLUSIONS: Topical CsA 0.05% was shown to have an inhibitory effect on immune-mediated corneal neovascularization in rabbits.

Carbon dioxide insufflation causes upper urinary tract injury in the early period of an experimental vesicoureteral reflux model.

PURPOSE: Ureteral reimplantation via pneumovesicum is a new aspect of vesicoureteral reflux management. We aimed to determine the effects of carbon dioxide (CO2) insufflation on the upper urinary tract in an experimental model. MATERIALS AND METHODS: Thirty New Zealand rabbits were allocated into five groups of six rabbits each. Right ureters were cannulated for CO2 insufflation in four groups. The pressures and durations of CO2 insufflation in the respective groups were as follows: Group A (10 mm Hg, 2 h); B (12 mm Hg, 2 h); C (10 mm Hg, 4 h); and D (12 mm Hg, 4 h) and control (E). Blood gas analysis, urea and creatinine levels were measured from renal veins and aorta. Histopathological evaluation of the renal parenchyma and ureters was scored. RESULTS: Significant histopathological changes were detected in the ipsilateral ureter and renal parenchyma exposed to CO2 insufflation, predominantly observed in groups insufflated for longer durations, p < 0.05. Blood gases drawn separately from renal veins were significantly more acidotic, and serum urea and creatinine levels were increased in all the groups, p < 0.05. CONCLUSIONS: CO2 causes significant histopathological and biochemical changes in the early period. Long-term results are required to determine whether permanent renal injury occurs.

Lithospermic acid and ischemia/reperfusion injury of the rat small intestine prevention.

BACKGROUND: Intestinal ischemia and reperfusion (I-R) injury of different causes, including cardiac insufficiency, sepsis, vasodepressant and cardiodepressant drugs, and complications of long-lasting surgery, represents a major clinical problem. OBJECTIVES: The purpose of the present study was to investigate whether lithospermic acid (LA) can reduce oxidative stress and histological damage in the rat small bowel subjected to mesenteric I-R injury. MATERIAL AND METHODS: The study was performed on three groups of animals, each composed of 7 rats: the SO (sham operation) group, the I-R/Untreated group and the I-R/LA (I-R plus LA pretreatment) group. Intestinal ischemia for 45 minutes and reperfusion for 60 minutes were applied. Ileum specimens were obtained to determine the tissue level of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and myeloperoxidase (MPO) activities and histological changes. RESULTS: Untreated intestinal I-R resulted in increased tissue MDA and MPO levels and diminished SOD and GPx activities. These changes were found to be almost reversed in the LA treatment group. Histopathologically, the intestinal injury in rats treated with LA was less than the untreated I-R group. CONCLUSIONS: Lithospermic acid attenuates mesenteric ischemia reperfusion injury in rat intestines by increasing tissue SOD and GPx activities and decreasing MDA and MPO levels. Lithospermic acid also improves morphological alterations which occurred after periods of reperfusion.

Histopathological evaluation of the effect of intranasal phototherapy on nasal mucosa in rabbits.

Allergic rhinitis is a high-incidence allergic inflammation of the nasal airways that impacts quality of life. Of the numerous therapies used to treat allergic rhinitis, intranasal phototherapy has emerged as a promising new treatment modality for inflammatory airway disease. Phototherapy is widely used for the treatment of immune-mediated skin diseases because its profound immunosuppressive effect inhibits hypersensitivity reactions in the skin. Intranasal phototherapy using a combination of Ultraviolet-A (UVA) and Ultraviolet-B (UVB) plus Visible light (VIS) has been shown to suppress the clinical symptoms of allergic rhinitis, but limited data regarding its adverse effects on the nasal mucosa currently exists. In this study, we demonstrate that UV displays no harmful effects on the nasal mucosa cells of rabbits following 2 weeks of intranasal phototherapy.