Journal Article

Apo866; Arthritis; In vivo; Living Image software; MMPSense 750 FAST; Xenogen Caliper IVIS 200

OBJECTIVE: Using APO866, studies assessed the ability of Pre-B-cell colony-Enhancing Factor (PBEF) to regulate inflammatory and degradative processes in fibroblasts and collagen-induced arthritis. METHODS: ELISAs were used to examine regulation of metalloproteinases and chemokine expression by HFF fibroblasts. PBEF was further examined in the collagen-induced arthritis model using APO866. Disease activity was assessed using radiography, histology, in vivo imaging and quantitative PCR (qPCR). RESULTS: In vitro activation of fibroblasts with PBEF promoted MMP-3, CCL-2 and CXCL-8 expression, an effect inhibited by APO866. Early intervention with APO866 in collagen-induced arthritis inhibited both synovial inflammation, including chemokine-directed leukocyte infiltration, and the systemic marker of inflammation, serum hyaluronic acid. Blockade of degenerative processes by APO866 was further illustrated by the reduced expression of MMP-3 and MMP-13 in joint extracts and reduction of the systemic marker of cartilage erosion, serum cartilage oligomeric matrix protein (COMP). Radiology showed that APO866 protected against bone erosion, whilst qPCR demonstrated inhibition of RANKL expression. APO866 treatment in established disease (clinical score >=5) reduced synovial inflammation, cartilage destruction and halted bone erosion. MMP-3, CCL-2 and RANKL activity, as assessed by in vivo imaging with MMPSense750 and qPCR were reduced in treated animals. qPCR of synovial explants from animals with CIA showed that APO866 inhibited MMP-3, CCL-2 and RANKL production, a result that was reversed with nicotinamide mononucleotide (NMN) CONCLUSIONS: These data confirm PBEF to be an important regulator of inflammation, cartilage catabolism and bone erosion, and highlights APO866 as a promising therapy for targeting PBEF activity in inflammatory arthritis.

Journal Article

matrix metalloproteinase; neuroendocrine; prostate cancer; metatasis

Prostate cancer is the leading form of cancer in men. Prostate tumors often contain neuroendocrine differentiation, which correlates with androgen-independent progression and poor prognosis. Matrix metalloproteinases (MMP), a family of enzymes that remodel the microenvironment, are associated with tumorigenesis and metastasis. To evaluate MMPs during metastatic prostatic neuroendocrine cancer development, we used transgenic mice expressing SV40 large T antigen in their prostatic neuroendocrine cells, under the control of transcriptional regulatory elements from the mouse cryptdin-2 gene (CR2-TAg). These mice have a stereotypical pattern of tumorigenesis and metastasis. MMP-2, MMP-7, and MMP-9 activities increased concurrently with the transition to invasive metastatic carcinoma, but they were expressed in different prostatic cell types: stromal, luminal epithelium, and macrophages, respectively. CR2-TAg mice treated with AG3340/Prinomastat, an MMP inhibitor that blocks activity of MMP-2, MMP-9, MMP-13, and MMP-14, had reduced tumor burden. CR2-TAg animals were crossed to mice homozygous for null alleles of MMP-2, MMP-7, or MMP-9 genes. At 24 weeks CR2-TAg; MMP-2-/- mice showed reduced tumor burden, prolonged survival, decreased lung metastasis, and decreased blood vessel density, whereas deficiencies in MMP-7 or MMP-9 did not influence tumor growth or survival. Mice deficient for MMP-7 had reduced endothelial area coverage and decreased vessel size, and mice lacking MMP-9 had increased numbers of invasive foci and increased perivascular invasion, as well as decreased tumor blood vessel size. Together, these results suggest distinct contributions by MMPs to the progression of aggressive prostate tumor and to helping tumors cleverly find alternative routes to malignant progression.

Journal Article

MMPSense, IVIS, Acrylamides/pharmacology/*therapeutic use; Animals; Arthritis, Experimental/*drug therapy/metabolism/pathology; Cartilage/*metabolism/pathology; Fibroblasts/metabolism/pathology; Humans; Inflammation/metabolism/pathology; Leukocytes/*drug effects/metabolism/pathology; Mice; Nicotinamide Phosphoribosyltransferase/*antagonists & inhibitors; Piperidines/pharmacology/*therapeutic use

OBJECTIVE: To assess the ability of pre-B cell colony-enhancing factor (PBEF) to regulate inflammation and degradative processes in inflammatory arthritis, using the small molecule inhibitor APO866 in human fibroblasts in vitro and in murine collagen-induced arthritis (CIA). METHODS: Enzyme-linked immunosorbent assays were used to examine regulation of expression of metalloproteinases and chemokines in human fibroblasts. The role of PBEF was further examined using APO866 in mice with CIA, with effects on disease activity assessed using radiography, histology, in vivo imaging, and quantitative polymerase chain reaction (qPCR). RESULTS: In vitro activation of human fibroblasts with PBEF promoted expression of matrix metalloproteinase 3 (MMP-3), CCL2, and CXCL8, an effect inhibited by APO866. In mice with CIA, early intervention with APO866 inhibited synovial inflammation, including chemokine-directed leukocyte infiltration, and reduced a systemic marker of inflammation, serum hyaluronic acid. APO866 blockade led to reduced expression of MMP-3 and MMP-13 in joint extracts and to a reduction in a systemic marker of cartilage erosion, serum cartilage oligomeric matrix protein. Radiologic images revealed that APO866 protected against bone erosion, while qPCR demonstrated inhibition of RANKL expression. In mice with established disease, APO866 reduced synovial inflammation and cartilage destruction, and halted bone erosion. In addition, APO866 reduced the activity of MMP-3, CCL2, and RANKL in vivo, and inhibited production of CCL2 and RANKL in synovial explants from arthritic mice, a result that was reversed with nicotinamide mononucleotide. CONCLUSION: These findings confirm PBEF to be an important regulator of inflammation, cartilage catabolism, and bone erosion, and highlight APO866 as a promising therapeutic agent for targeting PBEF activity in inflammatory arthritis.

Journal Article

MMPSense, IVIS

The Standard measures of experimental arthritis fail to detect, visualize, and quantify early inflammation and disease activity. Here, we describe the use of an injectable MMP-activated fluorescence agent for in vivo quantification of acute inflammation produced by collagen-antibody-induced arthritis (CAIA) in CC chemokine receptor-2 (Ccr2(-/-)) null mice. Although Ccr2(-/-) DBA1/J mice were highly susceptible to and rapidly developed CAIA, the standard clinical assessment of fore or hind paw thicknesses was unable to detect significant acute inflammatory changes (days 3-10). Remarkably, noninvasive, in situ, MMP-activatable fluorescent imaging of Ccr2(-/-) DBA1/J mice with CAIA displayed acute joint pathology in advance of clinically measurable acute inflammation (days 5, 7, and 10). These results were confirmed by the histology of ankle joints, which showed significant inflammation, bone loss, and synovial hyperplasia, compared to control mice at postimmunization day 5. The MMP-mediated fluorescence technique holds tremendous implications for quantifiable examination of arthritis disease activity of acute joint inflammation.

Journal Article

MMPSense, IVIS, Atherosclerosis/complications/*diagnosis; Carotid Stenosis/*diagnosis/etiology; Diagnostic Imaging/*methods; Humans; Reproducibility of Results

BACKGROUND: There is increasing evidence that plaque vulnerability, rather than the degree of stenosis, is important in predicting the occurrence of subsequent cerebral ischemic events in patients with carotid artery stenosis. The many imaging modalities currently available have different properties with regard to the visualization of the extent of vulnerability in carotid plaque formation. METHODS: Original published studies were identified using the MEDLINE database (January 1966 to March 2008). Manual cross-referencing was also performed. RESULTS: There is no single imaging modality that can produce definitive information about the state of vulnerability of an atherosclerotic plaque. Each has its own specific drawbacks, which may be the use of ionizing radiation or nephrotoxic contrast agents, an invasive character, low patient tolerability, or simply the paucity of information obtained on plaque vulnerability. Functional molecular imaging techniques such as positron emission tomography (PET), single photon emission-computed tomography (SPECT) and near infra-red spectroscopy (NIRS) do seem able accurately to visualize and even quantify features of plaque vulnerability and its pathophysiologic processes. Promising new techniques like near infra-red fluorescence imaging are being developed and may be beneficial in this field. CONCLUSION: There is a promising role for functional molecular imaging modalities like PET, SPECT, or NIRS related to improvement of selection criteria for carotid intervention, especially when combined with CT or MRI to add further anatomical details to molecular information. Further information will be needed to define whether and where this functional molecular imaging will fit into a clinical strategy.