Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease of the motor neuron system with limited therapeutic options. While an increasing number of ALS patients can be linked to a small number of autosomal-dominantly inherited cases, most cases are termed sporadic. Both forms are clinically and histopathologically indistinguishable, raising the prospect that they share key pathogenic steps, including potential therapeutic intervention points. The endocannabinoid system is emerging as a versatile, druggable therapeutic target in the CNS and its dysregulation is an early hallmark of neurodegeneration. Whether this is a defense mechanism or part of the pathogenesis remains to be determined. The neuroprotective and anti-inflammatory endocannabinoid 2-arachidonoylglycerol (2-AG), which is degraded by monoacylglycerol lipase (MAGL), accumulates in the spinal cords of transgenic models of ALS. We tested the hypothesis that this 2-AG increase is a protective response in the low-copy SOD1(G93A) mouse model of ALS. We show that oral application of the MAGL inhibitor KML29 delays disease onset, progression and survival. Furthermore, we could demonstrate that KML29 reduced proinflammatory cytokines and increased brain-derived neurotrophic factor (BDNF) expression levels in the spinal cord, the major site of neurodegeneration in ALS. Moreover, treatment of primary mouse neurons and primary mousecroglia with 2-AG confirmed the neuroprotective and anti-inflammatory action by increasing BDNF and arginase-1 and decreasing proinflammatory cytokines in vitro. In summary, we show that elevating 2-AG levels by MAGL inhibition is a therapeutic target in ALS and demonstrate that the endocannabinoid defense mechanisms can be exploited therapeutically in neurodegenerative diseases. This article is part of the Special Issue entitled "A New Dawn in Cannabinoid Neurobiology".
The modulation of the brain endocannabinoid system has been identified as an option to treat neurodegenerative diseases including Parkinson's disease (PD). Especially the elevation of endocannabinoid levels by inhibition of hydrolytic degradation represents a valuable approach. To evaluate whether monoacylglycerol lipase (MAGL) or fatty acid amide hydrolase (FAAH) inhibition could be beneficial for PD, we examined in parallel the therapeutic potential of the highly selective MAGL inhibitor KML29 elevating 2-arachidonoylglyerol (2-AG) levels and the highly selective FAAH inhibitor PF-3845 elevating anandamide (AEA) levels in a chronic methyl-4-phenyl-1,2,3,6-tetrahydropyridine/probenecid (MPTP/probenecid) mouse model of PD. Chronic administration of KML29 (10 mg/kg) but not PF-3845 (10 mg/kg) attenuated striatal MPTP/probenecid-induced dopamine depletion. Furthermore, KML29 induced an increase in Gdnf but not Bdnf expression, whereas PF-3845 decreased the MPTP/probenecid-induced Cnr2 expression without any effects on neurotrophin expression. Investigation of treatment-naive striatal mRNA levels revealed a high presence of Gdnf and Mgll in contrast to Bdnf and Faah. Treatment of primary mouse microglia with 2-AG increased Gdnf but not Bdnf expression, suggesting that microglia might mediate the observed KML29-induced increase in Gdnf. In summary, pharmacological MAGL but not FAAH inhibition in the chronic MPTP/probenecid model attenuated the MPTP/probenecid-induced effects on striatal dopamine levels which were accompanied by an increase in 2-AG levels.
AIMS The aim of this study was to determine the allele frequencies of resistance to inhibitors of cholinesterase 3 homologue RIC-3 gene rs1528133 polymorphism in overweight+obese+morbid obese and non-obese non-OB subjects The effects of rs1528133 genotypes on anthropometric diabetes and obesity related parameters self-reported macronutrient intake and drugs were also evaluated The study was performed on overweight+obese+morbid obese and non-obese subjects METHODS RIC-3 gene rs1528133 genotypes were determined with qPCR RESULTS The RIC-3 rs1528133 genotype frequencies were respectively as 89.4 for homozygous wild type A/A 10.6 for heterozygous A/C genotypes in overweight+obese+morbid obese patients and 92.7 for A/A 7.3 for A/C genotypes in non-OB subjects The homozygous mutant genotype C/C was not detected in our study population Genotype frequencies were not significantly different among study groups Heterozygous genotype carriers for the rs1528133 polymorphism were found to prefer higher glycemic load fat and protein diet content compared to homozygous wild type genotype carriers p=0.0001 The frequency of rs1528133 heterozygous individuals 16.7 using antihypertensive drugs was lower p=0.045 in comparison to wild type genotype carriers 46.9 in the whole study population CONCLUSIONS RIC-3 gene rs1528133 variation was not found to be effective over any analyzed obesity related parameter but associated with higher glycemic load protein and fat eating behavior and antihypertensive drug use.
Title: Phosphorylation sites of the nicotinic acetylcholine receptor. A novel site detected in position delta S362 Schroeder W, Meyer HE, Buchner K, Bayer H, Hucho F Ref: Biochemistry, 30:3583, 1991 : PubMed
The delta-subunit of the nicotinic acetylcholine receptor from Torpedo californica electric tissue isolated form receptor purified in the absence of protein phosphatase inhibitors contains a total of four phosphate groups. Three of these are shown to represent phosphoserine groups. The fourth possible represents phosphotyrosine. The phosphate groups are localized within the primary structure: We found phosphoserine in positions delta S361 and delta S377, the predicted sites phosphorylated by PKA and PKC, respectively. In addition, we found that position delta S362 is also phosphorylated. Phosphorylation experiments with the synthetic peptide delta L357-delta K368 show that phosphorylation of this novel site can be catalyzed by PKA and by PKC. It is concluded that the delat-subunit of the acetylcholine receptor is stably and not transiently phosphorylated. Implications for the physiological functions of receptor phosphorylation are discussed.
Certain recently developed antidotes of the bispyridinium type, commonly called "H-oximes" (HGG 12, 21, 42, 52, 65, 70, 89, and HGG 90) have been investigated as to their effects on muscarinic and nicotinic acetylcholine receptors. These compounds clearly discriminate between these two types of receptors being more potent inhibitors of the muscarinic receptor with inhibitory constants in the micromole range. (The corresponding values for the nicotinic receptor are in the range of 0.1 mM.) However, the inhibitory potency in the binding assay does not correlate with the ED50 values obtained against soman in mice. The site of antidotal action therefore appears not to be the nicotinic acetylcholine receptor. Binding to the muscarinic receptors may partially contribute to the effects against soman in vivo.
