Amyloid scavengers

A series of natural and synthetic products have also shown antiamyloid properties as amyloid scavengers or P-breakers. One example is the phenolic yellow curry pigment curcumin, which has potent anti-inflammatory and antioxidant activities and can suppress oxidative damage, inflammation, cognitive deficits, and amyloid... 

Tomiyama T, Shoji A, Kataoka K, Suwa Y, Asano S, Kaneko H, Endo N. Inhibition of amyloid beta protein aggregation neurotoxicity by rifampicin. Its possible function as a hydroxyl radical scavenger. J Biol Chem 1996 271 6839-6844. 

Tomiyama, T., Shoji, A., Kataoka, K., Suwa, Y., Asano, S., Kaneko, H., and Endo, N., Inhibition of amyloid beta protein aggregation and neurotoxicity by rifampicin its possible function as a hydroxyl radical scavenger, ]. Biol. Chem., 271, 6839,1996. 

Paresce DM, Ghosh RN, Maxfield FR. 1996. Microglial cells internalize aggregates of the Alzheimer s disease amyloid beta-protein via a scavenger receptor. Neuron 17(3) 553-565. 

Based on these considerations, LCM-directed 7P-OHC delivery to the Alzheimer s lesions may inhibit amyloid toxicity via gliosis and, potentially, reduce plaque pathology. Passage of the intravenously injected LCM/7p-OHC complex across the blood-brain barrier to Alzheimer s lesion sites should be readily possible in view of the earlier-mentioned fact that scavenger receptors, both... 

J. El Khoury, S.E. Hickman, C.A. Thomas, L. Cao, S.C. Silverstein and J.D. Loike, Scavenger receptor-mediated adhesion of microglia to P-amyloid fibrils, Nature 382 (1996) 716-719. 

Huang E, Buttini M, Wyss-Coray T, McConlogue L, Kodama T, Pitas RE, Mucke L (1999) Elimination of the class A scavenger receptor does not affect amyloid plaque formation or neurodegeneration in transgenic mice expressing human amyloid protein precursors. Am J Pathol 155 1741-1747. 

Li X, Yuan HF, Quan QK, Wang JJ, Wang NN, Li M (2011) Scavenging effect of Naoerkang on amyloid beta-peptide deposition in the hippocampus in a rat model of Alzheimer s disease. Chin J Integr Med 17 847-853... 

By biochemical and immunochemical techniques it is possible to stain three PHF components microtubule-associated protein (MAP), tau and ubiquitin. The question is whether the PHF represent intracellular amyloid deposits (Masters and Beyreuther, 1990). Both the PHF and extracellular amyloid plaques are formed from globular subunits that consist of aggregates of A4 protein. Experimentally, the amyloid protein precursor fragments are transformed to their insoluble aggregating form by meta-catalysin oxidation systems. This transformation can be prevented by radical scavengers (Dyrks et al., 1992). 

In screening indole compounds for neuroprotection against amyloid P-protein, potent neuropro-tective properties were uncovered for an endogenous related species, indole-3-propionic acid, the capacity of which to scavenge hydroxyl radicals exceeded that of melatonin (Chyan et al. 1999). 

Dote S, Bastianetto S, Kar S, Quirion R. Protective and rescuing abilities of IGF-I and some putative free radical scavengers against beta-amyloid-inducing toxicity in neurons. Ann NY Acad Sci 1999 890 356-364. 

Antioxidant neuroprotective effect on brain cells, spinal cord injury, 3-amyloid neurodegradation and against lipid peroxidation has been reported for extracts and flavonoids of St. John s wort. Different mechanisms seem to be involved, such as free radical scavenging, NOS inhibition and iron chelation, among others. ... 

Saffron extracts and their crocin compounds inhibit amyloid-beta protein deposition and improve learning and memory functions in mice which suggests a possible benefit in the management of Alzheimer s disease and other memory impairment conditions.This effect may be attributed to the antioxidant/ free radical scavenging activity frequently reported for saffron and its major constitu-... 

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