Abstract
The role of angiostatic factors, including endostatin, in regulating physiological angiogenesis is poorly understood. We used normal adult rats under physiological resting conditions to examine the relationship between tissue endostatin, VEGF, and capillary density (CD) in the heart (high metabolic activity) versus the skeletal muscle (relatively low metabolic activity). The heart (left ventricle, LV) and skeletal muscle (anterior tibialis, AT) were dissected from 12-week-old male Sprague–Dawley rats. Transverse cryosections of LV and AT were stained with FITC-conjugated GS-I-lectin. CD was determined by analysis of randomly acquired digital images of the cryosections using Optimas software. Tissue protein levels of endostatin and VEGF were determined by ELISA assays. Tissue endostatin levels were lower in the LV and higher in the AT (135 ± 39 vs. 663 ± 114 pg/mg) and VEGF levels were higher in the LV and lower in the AT (41 ± 3 vs. 27 ± 4 pg/mg), respectively (n = 7, P < 0.01). CD in LV and AT were 3632 ± 428 and 437 ± 44/mm2, respectively (P < 0.01). We demonstrated that an 8.3-fold greater capillary density is related to a 4.9-fold lower level of tissue endostatin and a 1.5-fold higher level of tissue VEGF in the heart (LV) versus the skeletal muscle (AT) of normal rats under physiological resting conditions. Also, exercise training increased capillary density, decreased tissue endostatin and increased tissue VEGF in the skeletal muscle (AT). These findings suggest that tissue endostatin content correlates inversely with capillary network in the muscle tissues with different metabolic activity, and that tissue endostatin may play a very important role in the metabolic control of angiogenesis under physiological conditions.
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References
O’Reilly MS, Holmgren L, Shing Y, et al. (1994) Angiogenesis: a novel angiogenesis inhibitor that mediates the suppression of metastases by Lewis lung carcinoma. Cell 79:315–328
Hanahan D, Folkman J (1996) Patterns and emerging mechanisms of the angiogenic switch during tumorigenesis. Cell 86:353–364
Ferrara N (2005) The role of VEGF in the regulation of physiological and pathological angiogenesis. EXS 94:209–231
Pages G, Pouyssegur J (2005) Transcriptional regulation of the vascular endothelia growth factor gene – a concert of activating factors. Cardiovasc Res 65:564–573
Gu JW, Adair TH (1997) Hypoxia induced expression of VEGF is reversible in myocardial vascular smooth muscle cells. Am J Physiol Heart Circ Physiol. 273:H628–H633
Folkman J (2002) Role of angiogenesis in tumor growth and metastasis. Semin Oncol 6:15–18
Patterson BC, San Q (1997) Angiostatin-converting enzyme activities of human matrilysin (MMP-7) and gelatinase B/type IV collagenase (MMP-9). J Biol Chem 272:28823–28825
Wen W, Moses MA, Wiederschain D, et al. (1999) The generation of endostatin is mediated by elastase. Cancer Res 59:6052–6056
Adair TH, Gay JW, Montani JP (1990) Growth regulation of the vascular system: evidence for a metabolic hypothesis. Am J Physiol Regulatory Integrative Comp Physiol 259:R393–R404
O’Reilly MS, Boehm T, Shing Y, et al. (1997) Endostatin: an endogenous inhibitor of angiogenesis and tumor growth. Cell 88:277–285
Hoppeler H, Kayer SR (1988) Capillary and oxidative capacity of muscles. News Physiol Sci 3:113–116
Mall G, Schkora I, Mattfeldt T, Bodle R (1987) Dipyridamole-induced neoformation of capillaries in the rat heart. Lab Invest 57:86–93
Gu JW, Fortepiani L, Reckelhoff J, et al. (2004) Increased expression of vascular endothelial growth factor and capillary density in hearts of Spontaneously Hypertensive Rats. Microcirculation 11:689–697
Folkman J (1995) Angiogenesis in cancer, vascular, rheumatoid, and other disease. Nat Med 1:27–31
Panchal VR, Rehman J, Nguyen AT, et al. (2004) Reduced pericardial levels of endostatin correlated with collateral development in patients with ischemic heart disease. J Am Coll Cariol 43:1383–1387
Bhutto IA, Kim SY, McLeod DS, et al. (2004) Localization of collagen XVII and the endostatin portion of collagen XVIII in aged human control eyes and eyes with age-related macular degeneration. Investigative Ophthalmol Visual Sci 45:1544–1552
Sund M, Hamano Y, Sugimoto H, et al. (2005) Function of endogenous inhibitiors of angiogenesis as endothelium-specific tumor suppressors. PNAS 102:2934–2939
Abdollahi A, Hahnfeldt P, Maercker C, et al. (2004) Endostatin’s antiangiogenic signaling network. Mol Cell 13:649–663
Yamaguchi N, Anand-Apte B, Lee M, et al. (1999) Endostatin inhibits VEGF-induced endothelial cell migration and tumor growth independently of zinc binding. EMBO J 18:4414–4432
Heljasvaara R, Nyberg P, Luostarinen J, et al. (2005) Generation of biologically active endostatin fragments from human collagen XVIII by distinct matrix metalloproteases. Exp Cell Res 307:292–304
Miosge N, Sasaki T, Timpl R (1999) Angiogenesis inhibitor endostatin is a distinct component of elastic fibers in vessel walls. FASEB J 13:1743–1750
Deininger MH, Fimmen BA, Thal DR, et al. (2002) Aberrant neuronal and paracellular deposition of endostatin in brains of patients with Alzheimer’s diseases. J Neurosci 22:10621–10626
Acknowledgements
This research is supported by grants from the National Heart, Lung, and Blood Institute (NIH HL-51971), the National Alcohol Abuse and Alcoholism Institute (NIH AA013821-01A2), and the American Cancer Society (IRG- 98-275-01). We would like to thank Dr. Radu Iliescu and Dr. Vasillios Kotsis for their thoughtful comments and suggestions in preparation of this manuscript.
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Gu, JW., Shparago, M., Tan, W. et al. Tissue Endostatin Correlates Inversely with Capillary Network in Rat Heart and Skeletal Muscles. Angiogenesis 9, 93–99 (2006). https://doi.org/10.1007/s10456-006-9035-z
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DOI: https://doi.org/10.1007/s10456-006-9035-z