Impact of Treadmill Running and Sex on Hippocampal Neurogenesis in the Mouse Model of Amyotrophic Lateral Sclerosis

Hippocampal neurogenesis in the subgranular zone (SGZ) of dentate gyrus (DG) occurs throughout life and is regulated by pathological and physiological processes. The role of oxidative stress in hippocampal neurogenesis and its response to exercise or neurodegenerative diseases remains controversial. The present study was designed to investigate the impact of oxidative stress, treadmill exercise and sex on hippocampal neurogenesis in a murine model of heightened oxidative stress (G93A mice). G93A and wild type (WT) mice were randomized to a treadmill running (EX) or a sedentary (SED) group for 1 or 4 wk. Immunohistochemistry was used to detect bromodeoxyuridine (BrdU) labeled proliferating cells, surviving cells, and their phenotype, as well as for determination of oxidative stress (3-NT; 8-OHdG). BDNF and IGF1 mRNA expression was assessed by in situ hybridization. Results showed that: (1) G93A-SED mice had greater hippocampal neurogenesis, BDNF mRNA, and 3-NT, as compared to WT-SED mice. (2) Treadmill running promoted hippocampal neurogenesis and BDNF mRNA content and lowered DNA oxidative damage (8-OHdG) in WT mice. (3) Male G93A mice showed significantly higher cell proliferation but a lower level of survival vs. female G93A mice. We conclude that G93A mice show higher hippocampal neurogenesis, in association with higher BDNF expression, yet running did not further enhance these phenomena in G93A mice, probably due to a ‘ceiling effect’ of an already heightened basal levels of hippocampal neurogenesis and BDNF expression

Olanzapine versus divalproex versus placebo in the treatment of mild to moderate mania: a randomized, 12-week, double-blind study.

OBJECTIVE: To evaluate the efficacy and safety of olanzapine, divalproex, and placebo in a randomized, double-blind trial in mild to moderate mania (DSM-IV-TR criteria). METHOD: The study was conducted from October 2004 to December 2006. A total of 521 patients from private practices, hospitals, and university clinics were randomly assigned to olanzapine (5-20 mg/day), divalproex (500-2500 mg/day), or placebo for 3 weeks; those completing continued with a 9-week double-blind extension. Efficacy (mean change in Young Mania Rating Scale [YMRS] total score was the primary outcome) and safety were assessed. RESULTS: After 3 weeks of treatment, olanzapine-treated (N = 215) and placebo-treated (N = 105) patients significantly differed in YMRS baseline-to-endpoint total score change (p = .034; least squares [LS] mean: -9.4 and -7.4, respectively). Such changes were not significantly different between olanzapine vs. divalproex (N = 201) or divalproex vs. placebo. After 12 weeks of treatment, olanzapine- and divalproex-treated patients significantly differed in YMRS baseline-to-endpoint changes (p = .004; LS mean: -13.3 and -10.7, respectively). Of observed cases, 35.4% (35/99; 3 weeks) to 57.1% (28/49; 12 weeks) had valproate plasma concentrations lower than the recommended valproate therapeutic range, but these patients' YMRS scores were lower than those of patients with valproate concentrations above/within range. Compared with divalproex, after 12 weeks, olanzapine-treated patients had significant increases in weight (p < .001) and in glucose (p < .001), triglyceride (p = .003), cholesterol (p = .024), uric acid (p = .027), and prolactin (p < .001) levels. Divalproex-treated patients had significant decreases in leukocytes (p = .044) and platelets (p < .001) compared with olanzapine after 12 weeks of treatment. The incidence of potentially clinically significant weight gain (>/= 7% from baseline) was higher with olanzapine than with divalproex (3-week: p = .064, 6.4% vs. 2.7%; 12-week: p = .002, 18.8% vs. 8.5%; respectively). CONCLUSION: Olanzapine was significantly more efficacious than placebo but not divalproex at 3 weeks and significantly more efficacious than divalproex at 12 weeks. Olanzapine-treated patients had significantly greater increases in weight and in glucose, cholesterol, triglyceride, uric acid, and prolactin levels than divalproex-treated patients. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00094549

The Right Rodent for the Job: Infarct Variability Between Strains and Its Impact on Logistics of Experimental Animal Studies

This chapter will discuss the variability in infarct size after ischaemic stroke in rat models of stroke, drawing example from our experience with the thread occlusion model. We will describe how the neuroprotective effect of a novel treatment diminished over the course of our testing, with post hoc analysis revealing wide variability in infarct volume in the experiments where the treatment was not shown to be protective. Application of various inclusion criteria failed to reduce variability, only reducing the number of animals. We then compared infarct variability in the Sprague-Dawley strain to other strains of rat used in our laboratory. The spontaneously hypertensive rat proved to be the most consistent strain of rat, having the least variable infarct volume, and stroke being successfully induced in all animals. The ability to include more animals in experimental groups is advantageous in terms of the absolute number of animals used, the time an experiment will take to complete and the cost of preclinical research