Inhibition by Anandamide of 6-Hydroxydopamine-Induced Cell Death in PC12 Cells

6-hydroxydopamine (6-OHDA) is a selective neurotoxin that is widely used to investigate cell death and protective strategies in models of Parkinson's disease. Here, we investigated the effects of the endogenous cannabinoid, anandamide, on 6-OHDA-induced toxicity in rat adrenal phaeochromocytoma PC12 cells. Morphological analysis and caspase-3 activity assay revealed that anandamide inhibited 6-OHDA-induced apoptosis. The protection was not affected by antagonists of either cannabinoid receptors (CB1 or CB2) or the vanilloid receptor TRPV1. Anandamide-dependent protection was reduced by pretreatment with LY294002 (inhibitor of phosphatidylinositol 3-kinase, PI3K) and unaffected by U0126 (inhibitor of extracellularly-regulated kinase). Interestingly, phosphorylation of c-Jun-NH2-terminal kinase (JNK) in cells exposed to 6-OHDA was strongly reduced by anandamide pre-treatment. Furthermore, 6-OHDA induced c-Jun activation and increased Bim expression, both of which were inhibited by anandamide. Together, these data demonstrate antiapoptotic effects of anandamide and also suggest a role for activation of PI3K and inhibition of JNK signalling in anandamide-mediated protection against 6-OHDA

Inhibition by Anandamide of 6-Hydroxydopamine-Induced Cell Death in PC12 Cells

6-hydroxydopamine (6-OHDA) is a selective neurotoxin that is widely used to investigate cell death and protective strategies in models of Parkinson's disease. Here, we investigated the effects of the endogenous cannabinoid, anandamide, on 6-OHDA-induced toxicity in rat adrenal phaeochromocytoma PC12 cells. Morphological analysis and caspase-3 activity assay revealed that anandamide inhibited 6-OHDA-induced apoptosis. The protection was not affected by antagonists of either cannabinoid receptors (CB1 or CB2) or the vanilloid receptor TRPV1. Anandamide-dependent protection was reduced by pretreatment with LY294002 (inhibitor of phosphatidylinositol 3-kinase, PI3K) and unaffected by U0126 (inhibitor of extracellularly-regulated kinase). Interestingly, phosphorylation of c-Jun-NH2-terminal kinase (JNK) in cells exposed to 6-OHDA was strongly reduced by anandamide pre-treatment. Furthermore, 6-OHDA induced c-Jun activation and increased Bim expression, both of which were inhibited by anandamide. Together, these data demonstrate antiapoptotic effects of anandamide and also suggest a role for activation of PI3K and inhibition of JNK signalling in anandamide-mediated protection against 6-OHDA.peer-reviewe

The behavioural and neuropathological impact of intranigral AAV-alpha-synuclein is exacerbated by systemic infusion of the Parkinson's disease-associated pesticide, rotenone, in rats

Despite the widely held belief that Parkinson's disease is caused by both underlying genetics and exposure to environmental risk factors, it is still widely modelled in preclinical models using a single genetic or neurotoxic insult. This single-insult approach has resulted in a variety of models that are limited with respect to their aetiological, construct, face and/or predictive validity. Thus, the aim of the current study was to investigate the interplay between genes and the environment as an alternative approach to modelling Parkinson's disease. To do so, rats underwent stereotaxic surgery for unilateral delivery of the Parkinson's disease-associated gene, alpha-synuclein, into the substantia nigra (using AAV vectors). This was followed 13 weeks later by subcutaneous implantation of an osmotic minipump delivering the Parkinson's disease-associated pesticide, rotenone (2.5 mg kg(-1) day(-1) for 4 weeks): The effect of the genetic and environmental insults alone or in combination on lateralised motor performance (Corridor, Stepping and Whisker Tests), nigrostriatal integrity (tyrosine hydroxylase immunohistochemistry) and alpha-synucleinopathy (alpha-synuclein immunohistochemistry) was assessed. We found that exposing AAV-alpha-synuclein-treated rats to rotenone led to a model in which the classical Parkinson's disease triad of progressive motor dysfunction, nigrostriatal neurodegeneration and alpha-synucleinopathy was evident. However, delivering rotenone systemically was also associated with bilateral motor dysfunction and loss of body weight. Thus, although we have shown that Parkinson's disease can be modelled in experimental animals by combined exposure to both genetic and environmental risk factors, this approach is limited by systemic toxicity of the pesticide rotenone. Direct intracerebral delivery of rotenone may be more useful in longer-term studies as we have previously shown that it overcomes this limitation. (C) 2013 Elsevier B.V. All rights reserved

Gamma band light stimulation in human case studies: Groundwork for potential Alzheimer's disease treatment

It is known that proteins associated with Alzheimer's disease (AD) pathogenesis are significantly reduced by 40¿Hz entrainment in mice. If this were to translate to humans, verifying that such a light stimulus can induce a 40¿Hz entrainment response in humans and harnessing insights from these case studies could be one step in the development of a multisensory device to prevent and treat AD. Verify the inducement of a 40¿Hz response in the human brain by a 40¿Hz light stimulus and obtain insights that could potentially aid in the development of a multisensory device for the prevention and treatment of AD. Electroencephalographic brain activity was recorded simultaneously with application of stimulus at different frequencies and intensities. Power spectral densities were analyzed. Entrainment to visual stimuli occurred with the largest response at 40¿Hz. The high intensity 40¿Hz stimulus caused widespread entrainment. The number of electrodes demonstrating entrainment increased with increasing light intensity. Largest amplitudes for the high intensity 40¿Hz stimulus were consistently found at the primary visual cortex. There was a harmonic effect at double the frequency for the 40¿Hz stimulus. An eyes-open protocol caused more entrainment than an eyes-closed protocol. It was possible to induce widespread entrainment using a 40¿Hz light stimulus in this sample cohort. Insights gleaned from these case studies could potentially aid in the development of a multisensory medical device to prevent and treat AD.peer-reviewe

Gamma band light stimulation in human case studies: Groundwork for potential Alzheimer\u27s disease treatment

It is known that proteins associated with Alzheimer\u27s disease (AD) pathogenesis are significantly reduced by 40¿Hz entrainment in mice. If this were to translate to humans, verifying that such a light stimulus can induce a 40¿Hz entrainment response in humans and harnessing insights from these case studies could be one step in the development of a multisensory device to prevent and treat AD. Verify the inducement of a 40¿Hz response in the human brain by a 40¿Hz light stimulus and obtain insights that could potentially aid in the development of a multisensory device for the prevention and treatment of AD. Electroencephalographic brain activity was recorded simultaneously with application of stimulus at different frequencies and intensities. Power spectral densities were analyzed. Entrainment to visual stimuli occurred with the largest response at 40¿Hz. The high intensity 40¿Hz stimulus caused widespread entrainment. The number of electrodes demonstrating entrainment increased with increasing light intensity. Largest amplitudes for the high intensity 40¿Hz stimulus were consistently found at the primary visual cortex. There was a harmonic effect at double the frequency for the 40¿Hz stimulus. An eyes-open protocol caused more entrainment than an eyes-closed protocol. It was possible to induce widespread entrainment using a 40¿Hz light stimulus in this sample cohort. Insights gleaned from these case studies could potentially aid in the development of a multisensory medical device to prevent and treat AD