Increasing bone strength with selected bisphosphonates

• US 6,416,737 B1
• Filed: 11/19/1999
• Issued: 07/09/2002
• Est. Priority Date: 11/19/1998
• Status: Expired due to Fees

• Current Assignee: Gador S. A., The Board of Trustees of the University of Arkansas (University of Arkansas System)
• Original Assignee: The Board of Trustees of the University of Arkansas (University of Arkansas System)
• Inventors: Bellido, Teresita, Manolagas, Stavros C.
• Primary Examiner(s): Dees, Jose G.
• Assistant Examiner(s): CHOI, FRANK I
• Application Number:
  US09/443,841
• Time in Patent Office: 963 Days
• Field of Search: 424/9.1, 424/9.2, 424/9.6, 436/103, 436/104, 436/106, 436/111, 436/127, 514/75, 514/102, 514/114, 514/139, 514/141
• US Class Current: 424/9.2
• CPC Class Codes: A61K 2300/00 Mixtures or combinations of active ingredients, wherein at least one active ingredient is fully defined in groups A61K31/00 - A61K41/00
• CPC Class Codes: A61K 31/166 having the carbon of a carboxamide group directly attached to the aromatic ring, e.g. procainamide, procarbazine, metoclopramide, labetalol
• CPC Class Codes: A61K 31/57 substituted in position 17 beta by a chain of two carbon atoms, e.g. pregnane or progesterone
• CPC Class Codes: A61K 31/663 Compounds having two or more phosphorus acid groups or esters thereof, e.g. clodronic acid, pamidronic acid
• CPC Class Codes: A61P 19/08 for bone diseases, e.g. rachitism, Paget's disease
• CPC Class Codes: A61P 19/10 for osteoporosis
• CPC Class Codes: G01N 2510/00 Detection of programmed cell death, i.e. apoptosis
• CPC Class Codes: G01N 33/5008 for testing or evaluating the effect of chemical or biological compounds, e.g. drugs, cosmetics
• CPC Class Codes: G01N 33/5011 for testing antineoplastic activity
• CPC Class Codes: G01N 33/502 for testing non-proliferative effects
• CPC Class Codes: G01N 33/5044 involving specific cell types
• CPC Class Codes: Y10T 436/16 Phosphorus containing
• CPC Class Codes: Y10T 436/163333 Organic [e.g., chemical warfare agents, insecticides, etc.]
• CPC Class Codes: Y10T 436/17 Nitrogen containing
• CPC Class Codes: Y10T 436/173845 Amine and quaternary ammonium
• CPC Class Codes: Y10T 436/20 Oxygen containing

Abstract

The present invention is a method and composition to increase bone strength in a manner that decreases fracture incidence, which may or may not include increasing bone mineral density (“BMD”). The invention includes administering an effective amount of a bisphosphonate to a host in need thereof to increase bone strength, which inhibits the apoptosis of osteoblasts and osteocytes, without a significant effect on osteoclasts. In one embodiment, the bisphosphonate is not 1-amino-3-(N,N-dimethylamino)-propyliden-1,1-bisphosphonic acid or its pharmaceutically acceptable salt. An increase in osteoblast life span can lead to an increase in bone mass, i.e., an anabolic effect. Preservation of osteocyte life span can increase bone strength, which may be disproportional to the increase in bone mass.

Claims

1. A method of screening for a compound that increases bone strength, that includes the steps of:

i. a) contacting osteocytes with a test compound; and

b) comparing the number of apoptotic osteocytes contacted with the test compound with the number of apoptotic osteocytes in a control wherein osteocytes are not contacted with the compound;

ii. a) contacting osteoblasts with the test compound; and

b) comparing the number of apoptotic osteoblasts contacted with the test compound with the number of apoptotic osteoblasts in a control wherein osteoblasts are not contacted with the test compound;

iii. a) contacting osteoclasts with the test compound; and

b) comparing the number of apoptotic osteoclasts contacted with the test compound with the number of apoptotic osteoclasts in a control wherein osteoclasts are not contacted with the test compound; and

iv. selecting a test compound that inhibits the apoptosis of osteocytes and osteoblasts and does not substantially affect the apoptosis of osteoclasts.

2. The method of claim 1, wherein said contacting occurs in vitro.

3. The method of claim 2, wherein said osteocytes are selected from the group consisting of MLO-Y4 cells and MLO-Y4 cells stably transfected with nuclear green fluorescent protein.

4. The method of claim 1, wherein said contacting occurs in vivo.

5. The method of claim 1, wherein said test compound is a bisphoshonate.

6. The method of claim 5, wherein said bisphosphonate is an amino-bisphosphonate.

7. The method of claim 1, wherein apoptosis of osteocytes is determined by a technique selected from the group consisting of fluorescent microscopy of MLO-Y4 cells stably transfected with nuclear green fluorescent protein, microscopy of stained cells, TUNEL analysis, Hoescht 33258 dye analysis, and video image analysis.