clove and Alzheimer-Disease

The β-amyloid peptide (1-42) is a molecule capable of aggregating into neurotoxic structures that have been implicated as potential etiological factors of Alzheimer's Disease. The aim of this study was to evaluate the inhibition of β-amyloid aggregation of ethyl acetate and ethanolic extracts obtained from Ugni molinae leaves on neurotoxic actions of β-amyloid aggregates. Chemical analyses were carried out with the extracts in order to determine their phenolic profile and its quantification. Both extracts showed a tendency to reduce neuronal deaths caused by β-amyloid. This tendency was inversely proportional to the evaluated concentrations. Moreover, the effect of EAE and ETE on β-amyloid aggregation was studied by fluorimetric T Thioflavin assay and transmission electronic microscopy (TEM); the extracts showed a modulation in the aggregation process. Partly, it is believed that these effects can be attributed to the polyphenolic compounds present in the extracts.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Humans; Myrtaceae; Peptide Fragments; Phenols; Plant Extracts; Plant Leaves

The aim of the study was to investigate the activity on β-amyloid peptide production of crude extracts of 9 plant species traditionally used in Benin or in Madagascar for the treatment of cognitive disorders, in order to select candidates for Alzheimer's disease treatment.. For each species, hexane, dichloromethane, ethyl-acetate and water extracts were tested, at non-toxic concentrations, on CHO cells overexpressing the human neuronal β-amyloid peptide precursor (APP695) to measure variations of APP processing (by Western-blotting) and, for the most active, of Aβ-amyloid production (by ECLIA).. We observed, at non-toxic concentrations, a significant increase in CTF/APP ratio with Oldenlandia affinis cyclotide-enriched fraction, Prosopis africana EtOAc extract, Pterocarpus erinaceus aqueous extract and Trichilia emetica hexane extract. We also showed that the Pterocarpus erinaceus extract significantly decreased Aβ production, displaying effects similar to those of DAPT (γ-secretase inhibitor) on APP processing, but may act on another inhibition site.. These active extracts are worth further studies to isolate the compounds responsible for the observed activities, to analyze their mode of action and determine their clinical potentials.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Benin; Blotting, Western; CHO Cells; Cognition Disorders; Cricetinae; Cricetulus; Humans; Madagascar; Medicine, Traditional; Plant Extracts; Plants, Medicinal

The volatile oil composition and anti-acetyl cholinesterase activity were analyzed in two specimens of Marlierea racemosa growing in different areas of the Atlantic Rain Forest (Cananéia and Caraguatatuba, SP, Brazil). Component identifications were performed by GC/MS and their acetyl cholinesterase inhibitory activity was measured through colorimetric analysis. The major constituent in both specimens was spathulenol (25.1% in Cananéia and 31.9% in Caraguatatuba). However, the first one also presented monoterpenes (41.2%), while in the Carguatatuba plants, this class was not detected. The oils from the plants collected in Cananéia were able to inhibit the acetyl cholinesterase activity by up to 75%, but for oils from the other locality the maximal inhibition achieved was 35%. These results suggested that the monoterpenes are more effective in the inhibition of acetyl cholinesterase activity than sesquiterpenes as these compounds are present in higher amounts in the M. racemosa plants collected in Cananéia.

Topics: Acetylcholinesterase; Alzheimer Disease; Brazil; Cholinesterase Inhibitors; Colorimetry; Gas Chromatography-Mass Spectrometry; Humans; Myrtaceae; Oils, Volatile; Tropical Climate