The effectiveness of different neuroprotective agents in facial nerve injury: An experimental study.

OBJECTIVES/HYPOTHESIS: To examine and compare the neuroprotective effects of dexamethasone, oxytocin, and resveratrol administration on regeneration after facial nerve crush injury in a rat model. STUDY DESIGN: Prospective, randomized, controlled animal study. METHODS: A crush-type facial nerve injury was performed on the right side of all rats (injury group [IG]), whereas there was no injury on the left side (sham group [SG]). These main groups were divided into five subgroups: 1) no medicine (control); 2) physiological serum; 3) dexamethasone; 4) oxytocin; and 5) resveratrol (Res) administered (intraperitoneal injection) for 28 days. Functional recovery was evaluated by daily eye-blink reflex and facial electromyography. Nerve-muscle degeneration and regeneration, apoptosis, and intercellular connections were evaluated in histopathological and immunohistochemical examinations. RESULTS: Recovery time of the postinjury eye-blink reflex demonstrated faster recovery in IG+Res when compared with the other subgroups. In peak-to-peak amplitude values, a significant increase was observed in the dexamethasone (P=0.007) and oxytocin subgroups (P=0.004) and was even more apparent in the resveratrol subgroup (P<0.001). Nerve regeneration is apparent in the resveratrol subgroup. Apoptotic changes were evaluated immunohistochemically with TUNEL and Caspase 3 and 6 antibodies staining. Caspase 3 and 6 immunoexpressions of resveratrol and oxytocin subgroups were moderate when compared with dexamethasone subgroup. Except for the resveratrol subgroup, which had an increase in expression, the majority of subgroups were similar to SG in terms of intercellular connections (Connexin 32 and 43). CONCLUSION: Resveratrol leads to the best outcome after facial nerve crush injury in rats when compared with dexamethasone and oxytocin, even though these agents demonstrate a significant improvement in facial nerve regeneration. LEVEL OF EVIDENCE: N/A.

Notch signaling-related therapeutic strategies with novel drugs in neuroblastoma spheroids.

Neuroblastoma is a severe pediatric tumor characterized by poor prognosis. Identification of novel molecular targets and diversion of investigations on new drug trials is mandatory for cancer therapy. In this study, vinorelbine tartrate, lithium chloride, clomipramine, and medroxyprogesterone acetate are used for the possible new treatment modalities in neuroblastoma cells. Notch and c-kit are novel molecules in cancer research, and Notch pathway is one of the emerging molecules in the neuroblastoma pathogenesis. Cytotoxic effects of these drugs at different time points, with different doses were studied in the SH-SY5Y human neuroblastoma cell line. Analysis of Notch and c-kit signaling with immunohistochemistry were constituted in multicellular tumor spheroids, and morphologic investigation was performed for digital imaging of cancer stem cells (CSCs) with electron microscopy. Size kinetics of spheroids was also determined after drug treatment. Results showed that all drugs were cytotoxic for neuroblastoma cells. Yet, this cytotoxic action did not correlate with the inhibitory effects in cell signaling. Neuroblastoma spheroids showed increased immunoreactivity of Notch signaling and c-kit. Altered ultrastructural CSCs morphology was observed after clomipramine and medroxyprogesterone acetate treatment compared with other drugs. Lithium chloride showed cellular membrane destruction for both CSCs and the remaining population. In this study, independent effects of cytotoxicity in tumor cells with respect to CSCs were determined. Redundant cells, which are the bulk population in tumor a compound, destroyed with therapy, were neither a target for treatment nor a remarkable investigation of cancer.

The effects of different intraabdominal pressure protocols in laparoscopic procedures on oxidative stress markers and morphology in rat ovaries.

BACKGROUND: To determine the effects of different intraabdominal pressure (IAP) on the ovaries in a laparoscopic rat model. OBJECTIVES: The aim of the study was to determine the effects on the ovaries of different intraabdominal pressures (IAP) in laparoscopic surgery in a rat model. MATERIAL AND METHODS: Thirty-two post-pubertal nonpregnant Sprague-Dawley rats were divided randomly into four groups. In the control group, no intraabdominal pressure (IAP) was applied. In Group Pp10 and Group Pp15, an IAP of 10 and 15 mm Hg, respectively, were applied by carbon dioxide insufflation for 60 min, and a 30-min desufflation was carried out. In Group IPp15, a 15 mm Hg IAP was applied for 10 min, and then CO2 was desufflated for 10 min. After this ischemic preconditioning, IAP was established at 15 mm Hg for 60 min, after which CO2 was desufflated for 30 min. Erythrocyte and ovarian tissue malondialdehyde (MDA) and histopathologic damage scores were evaluated. RESULTS: In Groups Pp10 and Pp15, ovarian tissue MDA values were significantly increased compared to the control group. In Groups Pp10 and Pp15, erythrocyte MDA values were significantly increased when compared to Group IPp15 and the control group. Ovarian histopatological assesment scores were significantly higher in Group Pp15 than in Groups Pp10 and IPp15. CONCLUSIONS: Pneumoperitoneum causes injuries to abdominal organ such as the ovaries. The ischemic preconditioning method is more effective in reducing oxidative stress due to laparoscopic pneumoperitoneum than low-pressure pneumoperitoneum methods.

The detrimental effects of diabetes on pluripotency determined by KLF4, SOX2, C-MYC and OCT4 immunoreactivity in rat testes.

BACKGROUND: Diabetes mellitus (DM) is a multisystem disorder. Type 1 DM can be experimentally induced in rats with streptozotocin (STZ). Diabetic conditions result in testicular oxidative stress and suppressed male reproductive activity as well as decreases in both testicular organ weights and subject weights. OBJECTIVES: The purpose of this study was to investigate immunohistochemical differences in testicular tissue due to STZ induced diabetes regarding pluripotency via transcription factors like Klf4, Sox2, c-Myc and Oct4, and to determine weight changes in both the subjects and the testes during the experiment. MATERIAL AND METHODS: Diabetes was induced in male adult rats for this study. A healthy control group and a diabetic group were observed for one month. Blood glucose levels over 250 mg/dL were considered diabetic. RESULTS: On days 0, 3, 15 and 30, the subjects' weights and testicular organ weights were determined and analyzed. The results revealed statistically significant decreases (p < 0.05 and p < 0.001, respectively). Semiquantitative immunohistochemical analyses of Klf4, Sox2, c-Myc and Oct4 were studied in testes paraffin sections via light microscopy. Decreased immunoreactivity of Klf4 was observed in the diabetic group in comparison to the controls. Spermatogonial cells and Sertoli cells showed increased immunostaining for Sox2 and c-Myc, while decreased immunoreactivity of Oct4 was noted for both spermatogenic and Sertoli cells compared to the control group. CONCLUSIONS: This study clearly demonstrated that Klf4, Sox2 and Oct4 immunopositive cells in adult male rat testes manifested sustainable pluripotency and that diabetes has dramatically detrimental effects on this trait.

Effects of Levetiracetam on neural tube development and closure of the chick embryos in ovo.

PURPOSE: Effects of Levetiracetam (LEV) within its therapeutic range at a 50 mg/kg dose for the chick embryo in ovo has been studied in order to demonstrate whether LEV would effect neural tube closure at the macroscopic morphology or LEV administered embryos still encounter neuroglial detrimental effects at the histological level. METHODS: Embryos were randomly seperated into control (n = 20) and study (n = 20) groups. The eggshell was windowed at specifically 24 h of incubation, and area underlying the membrane was excised to allow injection with 4.5 µl LEV in the study group, while physiologic saline (0.045 ml) were injected in the control group and each egg were re-incubated for 48 h more. Then, histological and immunohistochemical evaluation of the subjects were done. RESULTS: Macroscopic evaluation revealed immaturity of the placental vessel network in number and width for the study group in comparison to the controls. Defects of migration, decrease in the crista neuralis content, delay of the basal plates structures in the formation of the usual configuration, and delay in the cellular proliferation and the delay of development for the central nervous system were determined in the LEV-exposed group. Immunostaining of S100 proteins in this study has clearly demonstrated increased expression patterns of both neuroglial and neuronal cell populations. Toluidine blue stainings revealed mostly bipolar, differentiating neurons and crista neuralis cells which is concordant with active migration and differentiation. CONCLUSIONS: LEV found that delay in the closure of the neural tube and microcephalic fetuses disturb further morphological, biochemical, and functional development.

Evaluation of the immunomodulatory properties in mice and in vitro anti-inflammatory activity of cycloartane type saponins from Astragalus species.

ETHNOPHARMACOLOGICAL RELEVANCE: Astragalus roots are used to treat leukemia and for their wound healing properties in Southeast Anatolia-Turkey. MATERIALS AND METHODS: In vivo studies to investigate the effects of two Astragalus saponins were carried out on the immune response cytokines by using six to eight weeks old male Swiss albino mice. The production of IL-1ß, TGF-1ß, TNF-α, IL-2, IL-4 and IFN-γ cytokines was determined by ELISA. The spleen and lymph nodes, isolated from the mice subjects, were analyzed to realize induction of the surface antigen productions for IL-2Rα (CD25) and CD69. In addition, their effects on the targets of inflammation such as NF κB, iNOS and NAG-1 were investigated in cell-based assays. RESULTS: The results suggested that AST VII and Mac B had positive effect on Th1 cytokine release (IL-2 and IFN-γ), and suppression on Th2 cytokine production (IL-4). The immunohistochemical results exhibited induction of both IL-Rα (CD25) and CD69 surface receptors justifying the Th1 cytokine release. The compounds did not affect NF-κB or NAG-1 activity but iNOS activity was inhibited by Mac B with an IC(50) of 156 µg/ml. CONCLUSIONS: The results show that Ast VII and Mac B create powerful immunoregulatory effects without the stimulation of inflammatory cytokines in mice, and have no significant effect on the inflammatory cellular targets in vitro.