Compounds and methods for increasing neurogenesis

1. A method for increasing neurogenesis in neural tissue of a patient exhibiting at least one symptom of a central nervous system disorder selected from the group consisting of neurodegenerative disorders, ischemic disorders, neurological traumas, and learning and memory disorders, comprising:

administrating at least one agent selected from the group consisting of calcitonin, exendin and their analogs that elevate intracellular cAMP levels in the tissue, wherein the agent increases neurogenesis in the patient, thereby increasing neurogenesis in the neural tissue of the patient.

2. The method of claim 1 wherein said agent is a neurogenesis increasing agent selected from the group consisting of thyrocalcitonin, calcitonin, exendin-3, exendin-4, and analogs and combinations thereof.

3. The method of claim 2 wherein said agent is an calcitonin analog selected from the group consisting of katacalcin, calcitonin-gene-related-peptide, calcitonin-receptor-stimulating-peptides 1, calcitonin-receptor-stimulating-peptides 2, calcitonin-receptor-stimulating-peptides 3, histidine-methionine amide peptide hormone (PHM-27), Intermedin, side-chain bridged salmon calcitonin (Asp(17), Lys(21)), side-chain bridged salmon calcitonin (Asp(17) Orn(21)), a peptide comprising an amino acid sequence of SEQ ID NO:17 (AC512) benzophenone-containing calcitonin analogs, salmon calcitonin analog (Arg(11,18), Lys(14)), eel calcitonin analog, calcitonin 8-32, and analogs and combinations thereof.

4. The method of claim 2 wherein said agent is a calcitonin analog selected from the group consisting of calcitonin gene related peptide 8-37 (CGRP 8-37), amylin amide, and analogs thereof.

5. The method of claim 2 wherein said agent is an exendin analog selected from the group consisting of glucagon-like peptide-1 (GLP 1 peptide), glucagon-like peptide-1 analog, a polypeptide comprising an amino acid sequence of HA 8 EGTFTSDVSSYLEGQAAKEF IAWLVKGRK 37 wherein A 8 is a D-Ala and wherein a [2-[2-[2-maleimidopropionamido(ethoxy)ethoxy] acetamide is attached to the epsilon amino group of K 37 (CJC-1131), liraglutide, pramlintide, AVE-0010, (Ser2)-exendin (1-9), and alpha-me-glucagon-like peptide-1 (alpha-me-GLP-1).

6. The method of claim 1 wherein the agent is a glucagon-like peptide-1 (GIP-1) receptor ligand peptide or pituitary adenylate cyclase activating (PACAP) receptor ligand peptide.

7. The method of claim 1 wherein the nervous system disorder is selected from the group consisting of Parkinson's disease and Parkinsonian disorders, Huntington's disease, Alzheimers disease, multiple sclerosis, amyotrophic lateral sclerosis, Shy-prager syndrome, progressive supranuclear palsy, Lewy body disease, spinal ischemia, ischemic stroke, cerebral infarction, spinal cord injury, and cancer-related brain and spinal cord injury, multi-infarct dementia, geriatric dementia, cognition impairment and depression.

8. The method of claim 1 wherein increasing neurogenesis is modulating proliferation, differentiation, migration, or survival of a neural stem cells or progenitor cells in said neural tissue.

9. The method of claim 1 wherein said agent elevates the intracellular cAMP levels of said tissue above 20% as compared to a tissue not administered said agent.

10. The method of claim 1 wherein the agent is administered to the central nervous system of the patient.

11. The method of claim 1 wherein the agent is administered by a route selected from the group consisting of oral, subcutaneous, intraperitoneal, intramuscular, intracerebroventricular, intraparenchymal, intrathecal, intracranial, buccal, mucosal, nasal, and rectal administration.

12. The method of claim 1 wherein the agent is administered by a liposome delivery system.

13. The method of claim 1 wherein said increasing neurogenesis comprise maintaining or increasing the amount or percentage of doublecortin positive cells in the neural tissue relative to a patient not administered said agent.

14. The method of claim 1 wherein said increasing neurogenesis is performed by an activation of a G-protein coupled receptor (GPCR) in said neural tissue.

15. The method of claim 1 wherein the agent is administered to achieve a tissue concentration of 0.0001 nM to 50 nM.

16. A method for increasing neurogenesis in neural tissue of a patient exhibiting at least one symptom of a central nervous system disorder selected from the group consisting of neurodegenerative disorders, ischemic disorders, neurological traumas, and learning and memory disorders, comprising:

administrating at least one agent selected from the group consisting of thyrocalcitonin, calcitonin, exendin-3, exendin-4, and analogs and combinations thereof wherein the agent increases neurogenesis in the patient, thereby increasing neurogenesis in the neural tissue of the patient.