Nanotechnology is a multidisciplinary field involving the development of engineered devices at the atomic, molecular and macromolecular level, in the nanometer range (typically 1-100 nm). Recent advances in nanotechnology have raised exciting possibilities for the application of nanomaterials to biomedical imaging and the targeted delivery of drugs. We have recently developed a novel nanoparticle formulation with potent stimulatory effects on the formation of osteoblasts, the cells responsible for bone formation, and concomitant inhibitory effects on the formation of osteoclasts, the cells responsible for bone breakdown (resorption). This nanoparticle may have the potential to be developed into a powerful dual anticatabolic and proanabolic agent for the treatment of numerous osteoporotic diseases. However, before any reagent can be developed into a drug for use in humans it is imperative to understand the molecular and cellular mechanisms by which it regulates cell metabolism in order to assess its likely safety profile in vivo, and to understand potential toxic or non-specific side-effects on skeletal and non-skeletal cells. Our preliminary studies suggest that that this nanoparticle formulation achieves its stimulatory effects on osteoblasts, and inhibitory effects on osteoclasts, by a mechanism involving the suppression of the Nuclear Factor Kappa B (NF-kB) transcription factor. The NF-kB signal transduction pathway is established to be critical for production of bone resorbing osteoclasts in vitro and in vivo. By contrast, we and others have recently reported that the NF-kB pathway is potently inhibitory to osteoblastic differentiation and mineralization in vitro. Based on our preliminary data we hypothesize that this novel nanoparticle formulation inhibits osteoclast activity and stimulates osteoblast activity by suppressing the NF-kB signal transduction pathway.
In Specific Aim 1 we propose to investigate the action of this nanoparticle on the NF-kB signal transduction pathway in differentiating osteoclast and osteoblast precursors.
In Specific Aim 2 we will generate variants of the wild type nanoparticle possessing different physical and chemical properties including alterations to surface charge, surface decoration, and size, to determine which specific attributes are responsible for internalization entry into the cell, and biological action on the NF-kB pathway. Finally, in Specific Aim 3 we will evaluate the potential for this nanoparticle formulation to enhance bone mineral density and bone structure by stimulating osteoblastic bone formation and inhibiting osteoclastic bone resorption in mice in vivo.

Public Health Relevance

Nanotechnology has the power to revolutionize medicine. We recently developed a nanoparticle capable of inhibiting bone breakdown, while simultaneously stimulating new bone formation. We now seek to fully investigate the action of this particle on bone cells, and test its capacity to enhance bone mass in vivo.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Research Project (R01)
Project #
5R01AR056090-02
Application #
7649321
Study Section
Special Emphasis Panel (ZRG1-NANO-M (01))
Program Officer
Sharrock, William J
Project Start
2008-07-01
Project End
2011-06-30
Budget Start
2009-07-01
Budget End
2010-06-30
Support Year
2
Fiscal Year
2009
Total Cost
$327,555
Indirect Cost
Name
Emory University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
066469933
City
Atlanta
State
GA
Country
United States
Zip Code
30322
Titanji, Kehmia; Vunnava, Aswani; Foster, Antonina et al. (2018) T-cell receptor activator of nuclear factor-?B ligand/osteoprotegerin imbalance is associated with HIV-induced bone loss in patients with higher CD4+ T-cell counts. AIDS 32:885-894
Roser-Page, Susanne; Vikulina, Tatyana; Yu, Kanglun et al. (2018) Neutralization of CD40 ligand costimulation promotes bone formation and accretion of vertebral bone mass in mice. Rheumatology (Oxford) 57:1105-1114
Weitzmann, M Neale (2017) Bone and the Immune System. Toxicol Pathol 45:911-924
Neale Weitzmann, M; Pacifici, Roberto (2017) Parathyroid Diseases and T Cells. Curr Osteoporos Rep 15:135-141
Weitzmann, M Neale; Ofotokun, Ighovwerha (2016) Physiological and pathophysiological bone turnover - role of the immune system. Nat Rev Endocrinol 12:518-32
Moran, Caitlin A; Weitzmann, M Neale; Ofotokun, Ighovwerha (2016) The protease inhibitors and HIV-associated bone loss. Curr Opin HIV AIDS 11:333-42
Ofotokun, Ighovwerha; Titanji, Kehmia; Lahiri, Cecile D et al. (2016) A Single-dose Zoledronic Acid Infusion Prevents Antiretroviral Therapy-induced Bone Loss in Treatment-naive HIV-infected Patients: A Phase IIb Trial. Clin Infect Dis 63:663-671
Ofotokun, Ighovwerha; Titanji, Kehmia; Vikulina, Tatyana et al. (2015) Role of T-cell reconstitution in HIV-1 antiretroviral therapy-induced bone loss. Nat Commun 6:8282
Weitzmann, M Neale; Ha, Shin-Woo; Vikulina, Tatyana et al. (2015) Bioactive silica nanoparticles reverse age-associated bone loss in mice. Nanomedicine 11:959-967
Ha, Shin-Woo; Sikorski, James A; Weitzmann, M Neale et al. (2014) Bio-active engineered 50 nm silica nanoparticles with bone anabolic activity: therapeutic index, effective concentration, and cytotoxicity profile in vitro. Toxicol In Vitro 28:354-64

Showing the most recent 10 out of 39 publications