Dataset Information

Two-fold elevation of endogenous GDNF levels in mice improves motor coordination without causing side-effects.

ABSTRACT: Glial cell line-derived neurotrophic factor (GDNF) promotes the survival of dopaminergic neurons in vitro and in vivo. For this reason, GDNF is currently in clinical trials for the treatment of Parkinson's disease (PD). However, how endogenous GDNF influences dopamine system function and animal behavior is not fully understood. We recently generated GDNF hypermorphic mice that express increased levels of endogenous GDNF from the native locus, resulting in augmented function of the nigrostriatal dopamine system. Specifically, Gdnf?wt/hyper mice have a mild increase in striatal and midbrain dopamine levels, increased dopamine transporter activity, and 15% increased numbers of midbrain dopamine neurons and striatal dopaminergic varicosities. Since changes in the dopamine system are implicated in several neuropsychiatric diseases, including schizophrenia, attention deficit hyperactivity disorder (ADHD) and depression, and ectopic GDNF delivery associates with side-effects in PD models and clinical trials, we further investigated Gdnf?wt/hyper mice using 20 behavioral tests. Despite increased dopamine levels, dopamine release and dopamine transporter activity, there were no differences in psychiatric disease related phenotypes. However, compared to controls, male Gdnf?wt/hyper mice performed better in tests measuring motor function. Therefore, a modest elevation of endogenous GDNF levels improves motor function but does not induce adverse behavioral outcomes.

SUBMITTER: Matlik K

PROVIDER: S-EPMC6082872 | biostudies-other | 2018 Aug

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Two-fold elevation of endogenous GDNF levels in mice improves motor coordination without causing side-effects.

Mätlik Kärt K Võikar Vootele V Vilenius Carolina C Kulesskaya Natalia N Andressoo Jaan-Olle JO

Scientific reports 20180808 1

Glial cell line-derived neurotrophic factor (GDNF) promotes the survival of dopaminergic neurons in vitro and in vivo. For this reason, GDNF is currently in clinical trials for the treatment of Parkinson's disease (PD). However, how endogenous GDNF influences dopamine system function and animal behavior is not fully understood. We recently generated GDNF hypermorphic mice that express increased levels of endogenous GDNF from the native locus, resulting in augmented function of the nigrostriatal ...[more]

PMID: 30089897

Similar Datasets

Project description:Objective: In obese men, the increased expression of the aromatase enzyme in adipose tissue leads to high conversion of androgens to estrogens contributing to hypogonadotropic hypogonadism (HHG). Our objective is to evaluate efficacy and safety of weight loss (WL) plus aromatase inhibitor (AI) therapy in severely obese men with HHG. We hypothesize that AI+WL will be more effective as compared to WL alone in improving the hormonal profile, thus muscle strength and symptoms of HHG (primary outcomes), with no significant adverse effects on lean mass, metabolic profile, and bone mineral density (secondary outcomes). Design: Randomized double-blind placebo-controlled pilot trial. Methods: Twenty-three obese men (BMI≥35 kg/m2), 35-65 years old, were randomized to weight loss (diet and exercise) plus either anastrozole (AI+WL, n = 12) at 1 mg daily or placebo (PBO+WL, n = 11) for 6 months. Inclusion criteria: total testosterone <300 ng/mL (average of 2 measurements), estradiol≥10.9 pg/ml, LH <9 IU/l. Symptoms of hypogonadism by questionnaires; muscle strength by Biodex dynamometer; body composition and bone mineral density by dual-energy X-ray absorptiometry; bone microarchitecture and finite element analysis by high resolution peripheral quantitative-computed tomography. Results: After 6 months of therapy, AI+WL group had higher testosterone (p = 0.003) and lower estradiol (p = 0.001) compared to PBO+WL. Changes in symptoms and muscle strength did not differ between groups. AI+WL resulted in higher fat mass loss than PBO+WL (p = 0.04) without differences in changes in lean mass. Total and LDL cholesterol reduced more in the PBO+WL group compared to AI+WL (p = 0.03 for both), who experienced a minimal increase with unlikely meaningful clinical impact. Tibial trabecular bone area decreased more in PBO+WL than AI+WL group for which it remained stable (p = 0.03). Conclusions:Although AI+WL is effective in reversing the hormonal profile of HHG in severely obese men without causing major side effects, it does not lead to greater improvements in muscle strength and symptoms of hypogonadism compared to WL alone. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02959853.

Project description:Normal aging can result in a decline of memory and muscle function. Exercise may prevent or delay these changes. However, aging associated frailty may preclude physical activity. AMP-activated protein kinase (AMPK) is a transcriptional regulator important for muscle physiology. In the present study we investigated effects of AMPK agonist 5-aminoimidazole-4-carboxamide riboside (AICAR) on memory and motor function in young (2-month-old), aged (23-month-old) C57Bl/6 mice, and transgenic mice with muscle-specific mutated AMPK alpha-subunit (AMPK-DN). Mice were injected with AICAR (500 mg/kg) for 3 to 14 days and tested in the Morris water maze, rotarod and open field. Improved water maze performance and motor function was observed, albeit at longer duration of administration, in aged (14 days AICAR) than young (3 days AICAR) mice. In the AMPKDN mice, the compound did not enhance behavior, providing support for a muscle mediated mechanism. In addition, microarray analysis of muscle and hippocampal tissue derived from aged mice treated with AICAR revealed changes in gene expression in both tissues, which correlated with behavioral effects in a dose-dependent manner. Pronounced up-regulation of mitochondrial genes in muscle was observed. In the hippocampus genes relevant to neuronal development and plasticity were enriched. Altogether, endurance related factors may mediate both muscle and brain health in aging, and could play a role in new therapeutic interventions. Key words: Skeletal Muscle, Brain, Exercise, AMPK, Learning and Memory, Morris water maze 23-month old female C57BL/6J mice (Jackson Laboratory, Bar Harbor, ME) were housed under standard conditions, 3 mice per cage, with food and water ad libitum. Mice were injected intraperitoneally with 5-Aminoimidazole-4-carboxamide-1-a-D-ribofuranoside (AICAR, Toronto Research Chemicals Inc., Canada) dissolved in saline, 500 mg/kg/day for 3 (ACR3), 7 (ACR7) or 14 (ACR14) days or saline vehicle, for 3 (CTR) days. Thirty-three days after the final injection animals were deeply anesthetized with isofluorane and perfused transcardially with 0.9% NaCl solution. The gastrocnemius muscle and Hippocampus were quickly removed, frozen on dry ice and stored at M-bM-^HM-^R80 M-BM-0C for RNA isolation and microarray analysis.

Dataset Information

Two-fold elevation of endogenous GDNF levels in mice improves motor coordination without causing side-effects.

Publications

Two-fold elevation of endogenous GDNF levels in mice improves motor coordination without causing side-effects.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure