{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T11:33:42Z","timestamp":1791286422878,"version":"4.1.0"},"reference-count":34,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"2","content-domain":{"domain":["www.ahajournals.org"],"crossmark-restriction":true},"short-container-title":["Circulation"],"published-print":{"date-parts":[[2009,1,20]]},"abstract":"<jats:p>\n            <jats:bold>\n              <jats:italic>Background\u2014<\/jats:italic>\n            <\/jats:bold>\n            Chronic pressure overload causes myocardial hypertrophy, increased fibrillar collagen content, and abnormal diastolic function. We hypothesized that one determinant of these pressure overload\u2013induced changes is the extracellular processing of newly synthesized procollagen into mature collagen fibrils. We further hypothesized that secreted protein acidic and rich in cysteine (SPARC) plays a key role in post\u2013synthetic procollagen processing in normal and pressure-overloaded myocardium.\n          <\/jats:p>\n          <jats:p>\n            <jats:bold>\n              <jats:italic>Methods and Results\u2014<\/jats:italic>\n            <\/jats:bold>\n            To determine whether pressure overload\u2013induced changes in collagen content and diastolic function are affected by the absence of SPARC, age-matched wild-type (WT) and SPARC-null mice underwent either transverse aortic constriction (TAC) for 4 weeks or served as nonoperated controls. Left ventricular (LV) collagen content was measured histologically by collagen volume fraction, collagen composition was measured by hydroxyproline assay as soluble collagen (1 mol\/L NaCl extractable) versus insoluble collagen (mature cross-linked collagen), and collagen morphological structure was examined by scanning electron microscopy. SPARC expression was measured by immunoblot. LV, myocardial, and cardiomyocyte structure and function were assessed by echocardiographic, papillary muscle, and isolated cardiomyocyte studies. In WT mice, TAC increased LV mass, SPARC expression, myocardial diastolic stiffness, fibrillar collagen content, and soluble and insoluble collagen. In SPARC-null mice, TAC increased LV mass to an extent similar to WT mice. In addition, in SPARC-null mice, TAC increased fibrillar collagen content, albeit significantly less than that seen in WT TAC mice. Furthermore, the proportion of LV collagen that was insoluble was less in the SPARC-null TAC mice (86\u00b12%) than in WT TAC mice (99\u00b12%,\n            <jats:italic>P<\/jats:italic>\n            &lt;0.05), and the proportion of collagen that was soluble was greater in the SPARC-null TAC mice (14\u00b12%) than in WT TAC mice (1\u00b12%,\n            <jats:italic>P<\/jats:italic>\n            &lt;0.05) As a result, myocardial diastolic stiffness was lower in SPARC-null TAC mice (0.075\u00b10.005) than in WT TAC mice (0.045\u00b10.005,\n            <jats:italic>P<\/jats:italic>\n            &lt;0.05).\n          <\/jats:p>\n          <jats:p>\n            <jats:bold>\n              <jats:italic>Conclusions\u2014<\/jats:italic>\n            <\/jats:bold>\n            The absence of SPARC reduced pressure overload\u2013induced alterations in extracellular matrix fibrillar collagen and diastolic function. These data support the hypothesis that SPARC plays a key role in post\u2013synthetic procollagen processing and the development of mature cross-linked collagen fibrils in normal and pressure-overloaded myocardium.\n          <\/jats:p>","DOI":"10.1161\/circulationaha.108.773424","type":"journal-article","created":{"date-parts":[[2009,1,1]],"date-time":"2009-01-01T01:45:01Z","timestamp":1230774301000},"page":"269-280","update-policy":"https:\/\/doi.org\/10.1161\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":135,"title":["Pressure Overload\u2013Induced Alterations in Fibrillar Collagen Content and Myocardial Diastolic Function"],"prefix":"10.1161","volume":"119","author":[{"given":"Amy D.","family":"Bradshaw","sequence":"first","affiliation":[{"name":"From the Gazes Cardiac Research Institute, Division of Cardiology, Department of Medicine, RHJ Department of Veterans Affairs Medical Center, Medical University of South Carolina, Charleston."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Catalin F.","family":"Baicu","sequence":"additional","affiliation":[{"name":"From the Gazes Cardiac Research Institute, Division of Cardiology, Department of Medicine, RHJ Department of Veterans Affairs Medical Center, Medical University of South Carolina, Charleston."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tyler J.","family":"Rentz","sequence":"additional","affiliation":[{"name":"From the Gazes Cardiac Research Institute, Division of Cardiology, Department of Medicine, RHJ Department of Veterans Affairs Medical Center, Medical University of South Carolina, Charleston."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"An O.","family":"Van Laer","sequence":"additional","affiliation":[{"name":"From the Gazes Cardiac Research Institute, Division of Cardiology, Department of Medicine, RHJ Department of Veterans Affairs Medical Center, Medical University of South Carolina, Charleston."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Janet","family":"Boggs","sequence":"additional","affiliation":[{"name":"From the Gazes Cardiac Research Institute, Division of Cardiology, Department of Medicine, RHJ Department of Veterans Affairs Medical Center, Medical University of South Carolina, Charleston."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John M.","family":"Lacy","sequence":"additional","affiliation":[{"name":"From the Gazes Cardiac Research Institute, Division of Cardiology, Department of Medicine, RHJ Department of Veterans Affairs Medical Center, Medical University of South Carolina, Charleston."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael R.","family":"Zile","sequence":"additional","affiliation":[{"name":"From the Gazes Cardiac Research Institute, Division of Cardiology, Department of Medicine, RHJ Department of Veterans Affairs Medical Center, Medical University of South Carolina, Charleston."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","reference":[{"key":"e_1_3_2_1_2","doi-asserted-by":"publisher","DOI":"10.1001\/jama.289.19.2560"},{"key":"e_1_3_2_2_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.cir.0000039105.49749.6f"},{"key":"e_1_3_2_3_2","doi-asserted-by":"publisher","DOI":"10.1161\/circulationaha.105.573865"},{"key":"e_1_3_2_4_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.cir.0000017264.66561.3d"},{"key":"e_1_3_2_5_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(07)60980-5"},{"key":"e_1_3_2_6_2","doi-asserted-by":"publisher","DOI":"10.1161\/circulationaha.106.638569"},{"key":"e_1_3_2_7_2","doi-asserted-by":"publisher","DOI":"10.1093\/eurheartj\/16.suppl_C.38"},{"key":"e_1_3_2_8_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0955-0674(02)00361-7"},{"key":"e_1_3_2_9_2","doi-asserted-by":"publisher","DOI":"10.1172\/JCI12939"},{"key":"e_1_3_2_10_2","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M700167200"},{"key":"e_1_3_2_11_2","doi-asserted-by":"publisher","DOI":"10.1046\/j.1523-1747.2003.12241.x"},{"key":"e_1_3_2_12_2","doi-asserted-by":"publisher","DOI":"10.1177\/002215540205000101"},{"key":"e_1_3_2_13_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0002-9440(10)63856-4"},{"key":"e_1_3_2_14_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.echo.2005.10.005"},{"key":"e_1_3_2_15_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0735-1097(98)00550-6"},{"key":"e_1_3_2_16_2","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00480.2001"},{"key":"e_1_3_2_17_2","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00711.2001"},{"key":"e_1_3_2_18_2","doi-asserted-by":"publisher","DOI":"10.1161\/circulationaha.104.499202"},{"key":"e_1_3_2_19_2","doi-asserted-by":"publisher","DOI":"10.1007\/BF01002772"},{"key":"e_1_3_2_20_2","doi-asserted-by":"publisher","DOI":"10.1007\/BF00788278"},{"key":"e_1_3_2_21_2","first-page":"H308","volume":"261","year":"1991","unstructured":"Spinale FG, Tomita M, Zellner JL, Cook JC, Crawford FA, Zile MR. Collagen remodeling and changes in ventricular function during the development and regression of supraventricular tachycardia induced cardiomyopathy in swine. Am J Physiol. 1991; 261: H308\u2013H318.","journal-title":"Am J Physiol"},{"key":"e_1_3_2_22_2","doi-asserted-by":"publisher","DOI":"10.1161\/hyp.25.5.1111"},{"key":"e_1_3_2_23_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.86.2.513"},{"key":"e_1_3_2_24_2","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00654.2002"},{"key":"e_1_3_2_25_2","doi-asserted-by":"publisher","DOI":"10.1006\/jmcc.2000.1239"},{"key":"e_1_3_2_26_2","doi-asserted-by":"publisher","DOI":"10.1161\/circ.98.6.567"},{"key":"e_1_3_2_27_2","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.bi.64.070195.002155"},{"key":"e_1_3_2_28_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.res.0000264081.78659.45"},{"key":"e_1_3_2_29_2","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00816.2006"},{"key":"e_1_3_2_30_2","doi-asserted-by":"publisher","DOI":"10.1038\/nm1613"},{"key":"e_1_3_2_31_2","doi-asserted-by":"publisher","DOI":"10.2353\/ajpath.2007.061273"},{"key":"e_1_3_2_32_2","doi-asserted-by":"publisher","DOI":"10.1152\/physrev.00012.2007"},{"key":"e_1_3_2_33_2","unstructured":"Nimni ME. Fibrillar collagens: their biosynthesis molecular structure and mode of assembly. In: Zern MA Reid LM eds. Extracellular Matrix. New York NY: Marcel Dekker; 1993: 121\u2013148."},{"key":"e_1_3_2_34_2","first-page":"II-274.","volume":"114","year":"2006","unstructured":"Schellings MW, van Loon M, Sage H, Pinto YM, Heymans S. Loss of SPARC results in increased cardiac rupture and heart failure after acute myocardial infarction. Circulation. 2006; 114 (suppl II): II-274. Abstract.","journal-title":"Circulation"}],"container-title":["Circulation"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.ahajournals.org\/doi\/full\/10.1161\/CIRCULATIONAHA.108.773424","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,5,13]],"date-time":"2024-05-13T06:09:55Z","timestamp":1715580595000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.ahajournals.org\/doi\/10.1161\/CIRCULATIONAHA.108.773424"}},"subtitle":["Role of Secreted Protein Acidic and Rich in Cysteine (SPARC) in Post\u2013Synthetic Procollagen Processing"],"short-title":[],"issued":{"date-parts":[[2009,1,20]]},"references-count":34,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2009,1,20]]}},"alternative-id":["10.1161\/CIRCULATIONAHA.108.773424"],"URL":"https:\/\/doi.org\/10.1161\/circulationaha.108.773424","relation":{},"ISSN":["0009-7322","1524-4539"],"issn-type":[{"value":"0009-7322","type":"print"},{"value":"1524-4539","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,1,20]]},"assertion":[{"value":"2008-12-31","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}