Methods for inhibiting and reducing amyloid fibril formation associated with Alzheimer's Disease and other amyloidoses

#The invention relates to compositions and methods for treating Alzheimer's Disease and other amyloidoses; more particularly, it relates to compositions and methods for inhibiting and reducing amyloid fibril formation in therapeutic intervention in Alzheimer's disease and other amyloidoses.

#Alzheimer's disease is characterized by the accumulation of a 39-43 amino acid peptide termed the beta-amyloid protein or Aβ, in a fibrillar form, existing as extracellular amyloid plaques and as amyloid within the walls of cerebral blood vessels. Fibrillar Aβ amyloid deposition in Alzheimer's disease is believed to be detrimental to the patient and eventually leads to toxicity and neuronal cell death, characteristic hallmarks of Alzheimer's disease. Accumulating evidence implicates amyloid as a major causative factor of Alzheimer's disease pathogenesis.

#A variety of other human diseases also demonstrate amyloid deposition and usually involve systemic organs (i.e. organs or tissues lying outside the central nervous system), with the amyloid accumulation leading to organ dysfunction or failure. In Alzheimer's disease and “systemic” amyloid diseases, there is currently no cure or effective treatment, and the patient usually dies within 3 to 10 years from disease onset.

#FIG. 1 is a black and white graph of a 1 week Thioflavin T fluorometry assay utilized to identify inhibitors of Alzheimer's Aβ (1-40) amyloid fibril formation. Glucosamine (sulfate salt) containing Uncaria tomentosa (PTI-00700) is shown to be a potent inhibitor of Aβ (1-40) amyloid fibril formation.

#FIG. 2 is a black and white graph of a 1 week Thioflavin T fluorometry assay utilized to identify inhibitors of Alzheimer's Aβ (1-40) amyloid fibril formation. Glucosamine (sulfate salt) containing Uncaria tomentosa (PTI-00700), glucosamine (sulfate salt) containing Uncaria tomentosa (PTI-00700<30 kDa) which had gone through a filter with molecular weight cutoff of 30 kDa (PTI-00700<30 kDa), glucosamine (hydrochloride salt) containing Uncaria tomentosa (PTI-00701), and pure Uncaria tomentosa (PTI-00703) are all shown to be effective inhibitors of Alzheimer's Aβ amyloid fibril formation.

#FIG. 3 is a black and white graph of a solid phase binding assay utilized to identify lead compounds which inhibit Alzheimer's Aβ—Aβ interactions (i.e. Alzheimer's amyloid fibril growth). Glucosamine (sulfate salt) containing Uncaria tomentosa (PTI-00700) is identified as a potent inhibitor of Alzheimer's amyloid fibril growth.

#Turning now to the drawings, the invention will be described in a preferred embodiment by reference to the numerals of the drawing figures wherein like numbers indicate like parts.

#Amyloid and Amyloidosis

#Amyloid is a generic term referring to a group of diverse, but specific extracellular protein deposits which all have common morphological properties, staining characteristics, and x-ray diffraction spectra. Regardless of the nature of the amyloid protein deposited all amyloids have the following characteristics: 1) an amorphous appearance at the light microscopic level and appear eosinophilic using hematoxylin and eosin stains; 2) all stain with Congo red and demonstrate a red/green birefringence as viewed under polarized light (Puchtler et al., J. Histochem. Cytochem. 10:355-364, 1962), 3) all contain a predominant beta-pleated sheet secondary structure, and 4) ultrastructurally amyloid usually consist of non-branching fibrils of indefinite length and with a diameter of 7-10 nm.