Laboratory and clinical studies on the potential role of CBD in Parkinson's disease (PD), Alzheimer's disease (AD), multiple sclerosis (MS), Huntington's disease (HD), amyotrophic lateral sclerosis ALS), cerebral ischemia, were examined.
Remarkably, disturbances of ALS signaling were shared between SCA2p and sporadic PD suggesting common molecular dysfunctions in PD and ALS including CACNA1, hnRNP, DDX and PABPC gene family perturbations.
The finding of SOD variants in FALS is consistent with the hypothesis that free radicals contribute to the pathogenesis of FALS, and possibly to the pathogenesis of other neurodegenerative disorders such as Parkinson's disease, in which there is substantial evidence of oxidant stress.
Specific activity of the cuproprotein superoxide dismutase 1 was unchanged in the SN in PD but was enhanced in the parkinsonian anterior cingulate cortex, a region with α-synuclein pathology, normal Cu, and limited cell loss.
The loss of Cu,Zn-SOD m-RNA in SNc in MPTP-treated marmosets and patients with PD suggests that it is primarily located in dopaminergic neuronal cell bodies.
While among these iridoids, catalpol, 10-O-trans-p-coumaroylcatalpol, geniposide and harpagoside, in PD improved the expressions of GDNF and Bcl-2 proteins and TH-positive neurons by increasing the levels of antioxidant enzymes, SOD and GSH-P<sub>X</sub> and down-regulating insulin/IGF signalling via activation of MEK protein.
All the results indicated that KLF4 promoted the neurotoxicity of MPP + via inhibiting the transcription of SOD1, suggesting a potential mechanism of increased oxidative stress and cell death in Parkinson's disease.
The misfolded SOD1 was also detected in CSF from a subset of Parkinson's disease and progressive supranuclear palsy, albeit with smaller amounts than those in sALS.
Spinal cord from 11 ALS cases and 27 controls consisting of 15 cases of Alzheimer disease (AD), six cases of Parkinson disease (PD), three cases of cerebrovascular disease, and three control cases were analyzed.
Table 1 Biochemical Alterations in Substantia Nigra of Parkinson's Disease Indicating Oxidative Stress Elevated Decreased Iron (in microglia, astrocytes, oligodendrocytes, and melanized dopamine neurons and mitochondria) GSH (GSSG unchanged); GSH/GSSG ratio decreased Mitochondrial complex I Ferritin Calcium binding protein (calbindin 28) Mitochondrial monoamine oxidase B Transferrin and transferrin receptor Lipofuscin Vitamins E and C Ubiquitin Copper Cu/Zn-superoxide dismutase Cytotoxic cytokines (TNF-a, IL-1, IL-6) Inflammatory transcription factor NFKB Heme oxygenase-1 Ratio of oxidized to reduced glutathione (GSSG/GSH) Nitric oxide Neuromelanin.
In two different transgenic (Tg) mouse models of adult-onset neurodegenerative disease, a human A53T-α-synuclein (hαSyn) model of Parkinson's disease (PD) and a human G93A-superoxide dismutase-1(hSOD1) model of amyotrophic lateral sclerosis (ALS), mortality and survivor morbidity were significantly greater than non-Tg mice and a Tg mouse model of Alzheimer's disease after neonatal traumatic brain injury (TBI).
To evaluate the possibility of a shared genetic defect in amyotrophic lateral sclerosis and Parkinson's disease, the SOD1 gene was sequenced in index patients with familial Parkinson's disease from 23 families.No changes were detected.
In addition, those pathological neurofilament accumulations are known in α-synuclein in Parkinson's disease (PD), Aβ and tau in Alzheimer's disease (AD), polyglutamine in CAG trinucleotide repeat disorders, superoxide dismutase 1 (SOD1), TAR DNA-binding protein 43 (TDP43), neuronal FUS proteins, optineurin (OPTN), ubiquilin 2 (UBQLN2), and dipeptide repeat protein (DRP) in amyotrophic lateral sclerosis (ALS).
Ataxin-2 (ATXN2) polyglutamine domain expansions of large size result in an autosomal dominantly inherited multi-system-atrophy of the nervous system named spinocerebellar ataxia type 2 (SCA2), while expansions of intermediate size act as polygenic risk factors for motor neuron disease (ALS and FTLD) and perhaps also for Levodopa-responsive Parkinson's disease (PD).
Both ALS and PD are neurodegenerative diseases, and are characterized by the presence of intraneuronal inclusions; however, different classes of neurons are affected and the primary protein in the inclusions differs between the diseases, and in some cases is different in distinct forms of the same disease.
In particular, the principal isoform VDAC1 represents the main mitochondrial docking site of many misfolded proteins, such as amyloid β and Tau in Alzheimer's disease, α-synuclein in Parkinson's disease and several SOD1 mutants in Amyotrophic Lateral Sclerosis.
Epidemiological data have linked cadmium exposure to neurotoxicity and to neurodegenerative diseases (e.g., Alzheimer's and Parkinson's disease), and to increased risk of developing ALS.
Studies using invertebrate models expressing proteins associated with Huntington's disease, Alzheimer's disease, ALS, and Parkinson's disease have provided insights into the genetic networks and stress signaling pathways that regulate the proteostasis machinery to prevent cellular dysfunction, tissue pathology, and organismal failure.
We propose that these non-genetic factors underlie the misfolding and dysfunction of SOD1 and other proteins in both PD and fALS, constituting a shared and tractable pathway to neurodegeneration.