Interaction between the protective effects of cannabidiol and palmitoylethanolamide in experimental model of multiple sclerosis in C57BL/6 mice

Cannabinoids (CBs) have recently been approved to exert broad anti-inflammatory activities in experimental models of multiple sclerosis (MS). It has been demonstrated that these compounds could also have effects on neurodegeneration, demyelination, and autoimmune processes occurring in the pathology of MS. However, the clinical use of CBs is limited by their psychoactive effects. Among cannabinoid compounds, cannabidiol (CBD) and palmitoylethanolamide (PEA) have no psychotropic activities. We induced experimental autoimmune encephalomyelitis (EAE), a model of MS, by injecting myelin oligodendrocyte glycoprotein (MOG) to C57BL/6 mice. We assessed the effects of CBD, PEA, and co-administration of CBD and PEA on neurobehavioral scores, immune cell infiltration, demyelination, axonal injury, and the expression of inflammatory cytokines by using histochemistry methods and real-time RT-PCR. Treatment with either CBD (5mg/kg) or PEA (5mg/kg) during disease onset reduced the severity of the neurobehavioral scores of EAE. This effect of CBD and PEA was accompanied by diminished inflammation, demyelination, axonal damage and inflammatory cytokine expression while concurrent administration of CBD (5mg/kg) and PEA (5mg/kg) was not as effective as treatment with either drug per se. These results suggest that, CBD and PEA, non-psychoactive CBs, attenuate neurobehavioral deficits, histological damage, and inflammatory cytokine expression in MOG-immunized animals. However, there is an antagonistic interaction between CBD and PEA in protection against MOG-induced disease.

Restoration of Norepinephrine-Modulated Contextual Memory in a Mouse Model of Down Syndrome

Cognitive deficits in mice with a Down syndrome–like genetic defect can be reversed with precursors to the neurotransmitter norepinephrine.

Physical stability and aerosol properties of liposomes delivered using an air-jet nebulizer and a novel micropump device with large mesh apertures

The aerosol properties of liposomes and their physical stability to aerosolization were evaluated using an air-jet nebulizer (Pari LC Plus) and a customized large aperture vibrating-mesh nebulizer (Aeroneb Pro-8microm). Soya phosphatidylcholine: cholesterol (1:1 mole ratio) multilamellar liposomes (MLVs) entrapping salbutamol sulfate were nebulized directly, or after being reduced in size by extrusion through 1 or 0.4microm polycarbonate membrane filters. MLVs were very unstable to jet nebulization and stability was not markedly enhanced when vesicles were extruded before nebulization, such that drug losses from delivered liposomes using the Pari nebulizer were up to 88% (i.e. only 12% retained in liposomes). The Aeroneb Pro-8microm nebulizer was less disruptive to liposomes, completed nebulization in a much shorter time, and produced greater mass output rate than the Pari nebulizer. However, aerosol droplets were larger, total drug and mass outputs were lower and aerosolization performance was dependent on formulation. Vibrating-mesh nebulization was less disruptive to liposomes extruded through the 1microm membranes compared with the non-extruded MLVs, so that the retained entrapment of the drug in the nebulized vesicles was 56% and 37%, respectively. However, extrusion of liposomes to 0.4microm resulted in reduced stability of liposomes to vibrating-mesh nebulization (retained entrapment=41%) which was attributed to the reduced liposome lamellarity and subsequent reduced resistance to nebulization-induced shearing. This study has shown that vibrating-mesh nebulization using the customized large aperture mesh nebulizer (Aeroneb Pro-8microm) had a less disruptive effect on liposomes and produced a higher output rate compared with the Pari LC Plus air-jet nebulizer. On the other hand, the air-jet nebulizer produced higher total mass and drug outputs and smaller aerosol droplets.

Synthesis and calcium antagonist activity of 1,4-dihydropyridines containing phenylaminoimidazolyl substituents

Alkyl ester analogues of nifedipine, in which the ortho-nitrophenyl group at position 4 is replaced by 2-methylthio-1-phenylamino-5-imidazolyl substituent, were synthesized and evaluated as calcium-channel antagonists using the high K(+) contraction of guinea-pig ileal longitudinal smooth muscle. The results for the symmetrical esters showed that in the series of alkyl esters increasing the length of methylene chain in C-3 and C-5 ester substituents for more than two methylene units decreases activity. In the phenylalkyl ester series increasing the length of methylene chain also decreases activity. The results demonstrate that most of the compounds had similar activity to the reference drug nifedipine. In addition, two compounds, 5b and 5f were more active than the nifedipine.

The effect of mebudipine and dibudipine, two new Ca2+ channel blockers, in comparison with nifedipine on Ca2+ spikes of F1 neuronal soma membrane inHelix aspersa

Mebudipine and dibudipine are two new dihydropyridine (DHP) Ca2+ channel blockers that have been synthesized by Mahmoudian et al. (1997). In previous studies, they showed considerable relaxant effect on vascular and ileal smooth muscles. These two compounds also reduced the contraction force of rat left atrium (20, 22). In the present study, we attempted to compare the inhibitory actions of these new DHPs and nifedipine on the high threshold Ca2+ spikes of F1 neuronal soma membrane in the subesophageal ganglia of Helix aspersa, using current-clamp method. At a concentration of 1 microM, two new DHP compounds (mebudipine and dibudipine) were tested for their L-type Ca2+ channel blocker activity. Both compounds reversibly reduced the peak amplitude of action potential and after hyperpolarization potential and markedly decreased the duration of Ca2+ spikes. The most potent of these DHPs was mebudipine. Neither the two new DHPs nor nifedipine changed the resting membrane potential in a statistically significant way.

Synthesis and calcium channel blocker activity of alkyl 1,4-dihydro-2,6-dimethyl-4-nitrobenzyl thioimidazolyl-3,5-pyridinedicarboxylates

New alkyl ester analogues of nifedipine, in which the orthonitrophenyl group of position 4 is replaced by 1-methyl 2-(p-nitrobenzyl)thio-5-imidazolyl substituent, were synthesized and evaluated as calcium-channel antagonists using the high K+ contraction of guinea-pig ileal longitudinal smooth muscle. The results for the symmetrical esters showed that increasing the length of methylen chain in C3 and C5 ester substituents decreased activity. When the presence of bulky lipophilic esters increased activity. In unsymmetrical diester series, the results showed when R1 is a small substituent (R1 = Me), increasing of the lipophilic property in R2 substituent increased the activity if this high lipophilicity don't accompany with steric hinderance. Our results demonstrate that the most active compound was diphenyl ester derivative and it was almost seven times more active than the reference drug nifedipine.