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Digestive Enzyme Activity and Protein Degradation in Plasma of Heart Failure Patients. Cell Mol Bioeng 2021; 14:583-596. [PMID: 34900012 PMCID: PMC8630255 DOI: 10.1007/s12195-021-00693-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 07/20/2021] [Indexed: 11/11/2022] Open
Abstract
Introduction Heart failure is associated with degradation of cell functions and extracellular matrix proteins, but the trigger mechanisms are uncertain. Our recent evidence shows that active digestive enzymes can leak out of the small intestine into the systemic circulation and cause cell dysfunctions and organ failure. Methods Accordingly, we investigated in morning fasting plasma of heart failure (HF) patients the presence of pancreatic trypsin, a major enzyme responsible for digestion. Results Western analysis shows that trypsin in plasma is significantly elevated in HF compared to matched controls and their concentrations correlate with the cardiac dysfunction biomarker BNP and inflammatory biomarkers CRP and TNF-α. The plasma trypsin levels in HF are accompanied by elevated pancreatic lipase concentrations. The trypsin has a significantly elevated activity as determined by substrate cleavage. Mass spectrometry shows that the number of plasma proteins in the HF patients is similar to controls while the number of peptides was increased about 20% in HF patients. The peptides are derived from extracellular and intracellular protein sources and exhibit cleavage sites by trypsin as well as other degrading proteases (data are available via ProteomeXchange with identifier PXD026332). Connclusions These results provide the first evidence that active digestive enzymes leak into the systemic circulation and may participate in myocardial cell dysfunctions and tissue destruction in HF patients. Conclusions These results provide the first evidence that active digestive enzymes leak into the systemic circulation and may participate in myocardial cell dysfunctions and tissue destruction in HF patients. Supplementary Information The online version contains supplementary material available at 10.1007/s12195-021-00693-w.
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Chan AHW, Schmid-Schönbein GW. Pancreatic source of protease activity in the spontaneously hypertensive rat and its reduction during temporary food restriction. Microcirculation 2019; 26:e12548. [PMID: 30946505 DOI: 10.1111/micc.12548] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 03/20/2019] [Accepted: 04/02/2019] [Indexed: 01/06/2023]
Abstract
OBJECTIVE The mechanisms underlying cell and organ dysfunctions in hypertension are uncertain. The spontaneously hypertensive rat (SHR) has elevated levels of unchecked degrading proteases compared to the control Wistar Kyoto (WKY) rat. The extracellular proteases destroy membrane receptors leading to cell dysfunctions, including arteriolar constriction and elevated blood pressure. Our goal was to identify potential sources of the uncontrolled enzymatic activity. METHODS Zymographic and digital immunohistochemical measurements in SHR pancreas and intestine were obtained as part of the digestive system with high levels of degrading enzymes. OBJECTIVE The results showed that SHRs have significantly higher protease activity than WKY in pancreas (22.04 ± 9.01 vs 13.02 ± 3.92 casein fluorescence intensity unit; P < 0.05) and pancreatic venules (0.011 ± 0.003 vs 0.005 ± 0.003 trypsin absorbance; P < 0.05) as well as in venous blood (71.07 ± 13.92 vs 36.44 ± 16.59 casein fluorescence intensity unit; P < 0.05). The enzymatic activity is contributed by trypsin and chymotrypsin. Furthermore, a decrease of these enzyme activity levels achieved during a short-term fasting period is associated with a reduction in systolic blood pressurein SHR (135 ± 8 mm Hg vs 124 ± 7 mm Hg; P < 0.05). CONCLUSIONS The results suggest the pancreas of the SHR is a potential source for serine proteases leaking into the circulation and contributing to its protease activity.
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Affiliation(s)
- Amy Hsueh Wen Chan
- Department of Bioengineering, Institute of Engineering in Medicine, University of California San Diego, San Diego, California
| | - Geert W Schmid-Schönbein
- Department of Bioengineering, Institute of Engineering in Medicine, University of California San Diego, San Diego, California
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Cirrik S, Schmid-Schönbein GW. IGF-1 receptor cleavage in hypertension. Hypertens Res 2018; 41:406-413. [PMID: 29556095 PMCID: PMC8075889 DOI: 10.1038/s41440-018-0023-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 09/08/2017] [Accepted: 10/18/2017] [Indexed: 12/25/2022]
Abstract
Increased protease activity causes receptor dysfunction due to extracellular cleavage of different membrane receptors in hypertension. The vasodilatory effects of insulin-like growth factor-1 (IGF-1) are decreased in hypertension. Therefore, in the present study the association of an enhanced protease activity and IGF-1 receptor cleavage was investigated using the spontaneously hypertensive rats (SHRs) and their normotensive Wistar Kyoto (WKY) controls (n = 4). Matrix metalloproteinase (MMP) activities were determined using gelatin zymography on plasma and different tissue samples. WKY aorta rings were incubated in WKY or SHR plasma with or without MMP inhibitors, and immunohistochemistry was used to quantify the densities of the alpha and beta IGF-1 receptor (IGF-1R) subunits and to determine receptor cleavage. The pAkt and peNOS levels in the aorta were investigated using immunoblotting as a measure of IGF-IR function. Increased MMP-2 and MMP-9 activities were detected in plasma and peripheral tissues of SHRs. IGF-1R beta labeling was similar in both groups without plasma incubation, but the fraction of immunolabeled area for IGF-1R alpha was lower in the endothelial layer of the SHR aorta (p < 0.05). A 24-h incubation of WKY aorta with SHR plasma did not affect the IGF-1R beta labeling density, but reduced the IGF-1R alpha labeling density in the endothelium (p < 0.05). MMP inhibitors prevented this decrease (p < 0.01). Western blot analyses revealed that the pAkt and peNOS levels under IGF-1-stimulated and -unstimulated conditions were lower in SHRs (p < 0.05). A reduced IGF-1 cellular response in the aorta was associated with the decrease in the IGF-1R alpha subunit in the SHR hypertension model. Our results indicate that MMP-dependent receptor cleavage contributed to the reduced IGF-1 response in SHRs.
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Affiliation(s)
- Selma Cirrik
- Department of Physiology, Faculty of Medicine, Ordu University, Ordu, Turkey.
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Mechanisms of I/R-Induced Endothelium-Dependent Vasodilator Dysfunction. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2017; 81:331-364. [PMID: 29310801 DOI: 10.1016/bs.apha.2017.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Ischemia/reperfusion (I/R) induces leukocyte/endothelial cell adhesive interactions (LECA) in postcapillary venules and impaired endothelium-dependent, NO-mediated dilatory responses (EDD) in upstream arterioles. A large body of evidence has implicated reactive oxygen species, adherent leukocytes, and proteases in postischemic EDD dysfunction in conduit arteries. However, arterioles represent the major site for the regulation of vascular resistance but have received less attention with regard to the mechanisms underlying their reduced responsiveness to EDD stimuli in I/R. Even though leukocytes do not roll along, adhere to, or emigrate across arteriolar endothelium in postischemic intestine, recent work indicates that I/R-induced venular LECA is causally linked to EDD in arterioles. An emerging body of evidence suggests that I/R-induced EDD in arterioles occurs by a mechanism that is triggered by LECA in postcapillary venules and involves the formation of signals in the interstitium elicited by the proteolytic activity of emigrated leukocytes. This activity releases matricryptins from or exposes matricryptic sites in the extracellular matrix that interact with the integrin αvβ3 to induce mast cell chymase-dependent formation of angiotensin II (Ang II). Subsequent activation of NAD(P)H oxidase by Ang II leads to the formation of oxidants which inactivate NO and leads to eNOS uncoupling, resulting in arteriolar EDD dysfunction. This work establishes new links between LECA in postcapillary venules, signals generated in the interstitium by emigrated leukocytes, mast cell degranulation, and impaired EDD in upstream arterioles. These fundamentally important findings have enormous implications for our understanding of blood flow dysregulation in conditions characterized by I/R.
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Luizon MR, Palei ACT, Cavalli RC, Sandrim VC. Pharmacogenetics in the treatment of pre-eclampsia: current findings, challenges and perspectives. Pharmacogenomics 2017; 18:571-583. [DOI: 10.2217/pgs-2016-0198] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Pre-eclampsia (PE) is defined as pregnancy-induced hypertension and proteinuria, and is a major cause of maternal and perinatal morbidity and mortality. A large subgroup of pregnant women with PE is nonresponsive to antihypertensive drugs, including methyldopa, nifedipine and hydralazine. Pharmacogenomics may help to guide the individualized therapy for this nonresponsive subgroup. However, just a few pharmacogenetic studies examined the effects of genetic polymorphisms on response to antihypertensive drugs in PE, and the criteria of responsiveness used to define responsive or nonresponsive subgroups to antihypertensive therapy should be replicated by others. We review these gene–drugs interactions, novel approaches to pharmacogenomics research and potential novel drugs for PE therapy. Finally, we discuss the challenges and perspectives of pharmacogenetics in the treatment of PE.
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Affiliation(s)
- Marcelo R Luizon
- Department of Pharmacology, Institute of Biosciences of Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, Sao Paulo 18680-000, Brazil
- Department of General Biology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais 31270-901, Brazil
| | - Ana CT Palei
- Department of Surgery, Division of Pediatric & Congenital Heart Surgery, University of Mississippi Medical Center, Jackson, MS 39216, USA
- Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Ricardo C Cavalli
- Department of Gynecology & Obstetrics, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Sao Paulo 14049-900, Brazil
| | - Valeria C Sandrim
- Department of Pharmacology, Institute of Biosciences of Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, Sao Paulo 18680-000, Brazil
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Almalki SG, Llamas Valle Y, Agrawal DK. MMP-2 and MMP-14 Silencing Inhibits VEGFR2 Cleavage and Induces the Differentiation of Porcine Adipose-Derived Mesenchymal Stem Cells to Endothelial Cells. Stem Cells Transl Med 2017; 6:1385-1398. [PMID: 28213979 PMCID: PMC5442711 DOI: 10.1002/sctm.16-0329] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 12/19/2016] [Accepted: 01/06/2017] [Indexed: 12/27/2022] Open
Abstract
The molecular mechanisms that control the ability of adipose‐derived mesenchymal stem cells (AMSCs) to remodel three‐dimensional extracellular matrix barriers during differentiation are not clearly understood. Herein, we studied the expression of matrix metalloproteinases (MMPs) during the differentiation of AMSCs to endothelial cells (ECs) in vitro. MSCs were isolated from porcine abdominal adipose tissue, and characterized by immunopositivity to CD44, CD90, CD105, and immunonegativity to CD14 and CD45. Plasticity of AMSCs was confirmed by multilineage differentiation. The mRNA transcripts for MMPs and Tissue Inhibitor of Metalloproteinases (TIMPs), and protein expression of EC markers were analyzed. The enzyme activity and protein expression were analyzed by gelatin zymography, enzyme‐linked immunosorbent assay (ELISA), and Western blot. The differentiation of AMSCs to ECs was confirmed by mRNA and protein expressions of the endothelial markers. The mRNA transcripts for MMP‐2 and MMP‐14 were significantly increased during the differentiation of MSCs into ECs. Findings revealed an elevated MMP‐14 and MMP‐2 expression, and MMP2 enzyme activity. Silencing of MMP‐2 and MMP‐14 significantly increased the expression of EC markers, formation of capillary tubes, and acetylated‐low‐density lipoprotein uptake, and decreased the cleavage of vascular endothelial growth factor receptor type 2 (VEGFR2). Inhibition of VEGFR2 significantly decreased the expression of EC markers. These novel findings demonstrate that the upregulation of MMP2 and MMP14 has an inhibitory effect on the differentiation of AMSCs to ECs, and silencing these MMPs inhibit the cleavage of VEGFR2 and stimulate the differentiation of AMSCs to ECs. These findings provide a potential mechanism for the regulatory role of MMP‐2 and MMP‐14 in the re‐endothelialization of coronary arteries following intervention. Stem Cells Translational Medicine2017;6:1385–1398
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Affiliation(s)
- Sami G Almalki
- Department of Clinical and Translational Science, Creighton University School of Medicine, Omaha, Nebraska, USA
| | - Yovani Llamas Valle
- Department of Clinical and Translational Science, Creighton University School of Medicine, Omaha, Nebraska, USA
| | - Devendra K Agrawal
- Department of Clinical and Translational Science, Creighton University School of Medicine, Omaha, Nebraska, USA
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Burkhardt D, Bartosova M, Schaefer B, Grabe N, Lahrmann B, Nasser H, Freise C, Schneider A, Lingnau A, Degenhardt P, Ranchin B, Sallay P, Cerkauskiene R, Malina M, Ariceta G, Schmitt CP, Querfeld U. Reduced Microvascular Density in Omental Biopsies of Children with Chronic Kidney Disease. PLoS One 2016; 11:e0166050. [PMID: 27846250 PMCID: PMC5113061 DOI: 10.1371/journal.pone.0166050] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 10/21/2016] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Endothelial dysfunction is an early manifestation of cardiovascular disease (CVD) and consistently observed in patients with chronic kidney disease (CKD). We hypothesized that CKD is associated with systemic damage to the microcirculation, preceding macrovascular pathology. To assess the degree of "uremic microangiopathy", we have measured microvascular density in biopsies of the omentum of children with CKD. PATIENTS AND METHODS Omental tissue was collected from 32 healthy children (0-18 years) undergoing elective abdominal surgery and from 23 age-matched cases with stage 5 CKD at the time of catheter insertion for initiation of peritoneal dialysis. Biopsies were analyzed by independent observers using either a manual or an automated imaging system for the assessment of microvascular density. Quantitative immunohistochemistry was performed for markers of autophagy and apoptosis, and for the abundance of the angiogenesis-regulating proteins VEGF-A, VEGF-R2, Angpt1 and Angpt2. RESULTS Microvascular density was significantly reduced in uremic children compared to healthy controls, both by manual imaging with a digital microscope (median surface area 0.61% vs. 0.95%, p<0.0021 and by automated quantification (total microvascular surface area 0.89% vs. 1.17% p = 0.01). Density measured by manual imaging was significantly associated with age, height, weight and body surface area in CKD patients and healthy controls. In multivariate analysis, age and serum creatinine level were the only independent, significant predictors of microvascular density (r2 = 0.73). There was no immunohistochemical evidence for apoptosis or autophagy. Quantitative staining showed similar expression levels of the angiogenesis regulators VEGF-A, VEGF-receptor 2 and Angpt1 (p = 0.11), but Angpt2 was significantly lower in CKD children (p = 0.01). CONCLUSIONS Microvascular density is profoundly reduced in omental biopsies of children with stage 5 CKD and associated with diminished Angpt2 signaling. Microvascular rarefaction could be an early systemic manifestation of CKD-induced cardiovascular disease.
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Affiliation(s)
- Dorothea Burkhardt
- Department of Pediatric Nephrology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Maria Bartosova
- Center for Pediatric and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
| | - Betti Schaefer
- Center for Pediatric and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
| | - Niels Grabe
- Bioquant, Hamamatsu Tissue Imaging and Analysis (TIGA) Center, University of Heidelberg, Heidelberg, Germany
| | - Bernd Lahrmann
- Bioquant, Hamamatsu Tissue Imaging and Analysis (TIGA) Center, University of Heidelberg, Heidelberg, Germany
| | - Hamoud Nasser
- Center for Cardiovascular Research, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Christian Freise
- Center for Cardiovascular Research, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Axel Schneider
- Department of Pediatric Surgery, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Anja Lingnau
- Department of Pediatric Urology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Petra Degenhardt
- Department of Pediatric Surgery, Charité-Universitätsmedizin Berlin, Berlin, Germany
- Department of Pediatric Surgery, Klinikum Ernst von Bergmann, Potsdam, Germany
| | - Bruno Ranchin
- Hospices Civils de Lyon, Service de Nephrologie Pediatrique and Epicime-Centre d’Investigation Clinique 1407, Hopital Femme Mere Enfant, Lyon, France
| | - Peter Sallay
- First Department of Pediatrics, Semmelweis University, Budapest, Hungary
| | - Rimante Cerkauskiene
- Coordinating Centre for Children’s Rare Diseases, Children´s Hospital, Affiliate of Vilnius University Hospital Santariskiu Klinikos, Vilnius, Lithuania
| | - Michal Malina
- Department of Pediatrics, Second Faculty of Medicine, Charles University-Prague, Prague 5, Czech Republic
| | - Gema Ariceta
- Servicio de Nefrología Pediátrica, Hospital Universitari Vall d’Hebron, Barcelona, Spain
| | - Claus Peter Schmitt
- Center for Pediatric and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
| | - Uwe Querfeld
- Department of Pediatric Nephrology, Charité-Universitätsmedizin Berlin, Berlin, Germany
- Center for Cardiovascular Research, Charité Universitätsmedizin Berlin, Berlin, Germany
- * E-mail:
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Mazor R, Schmid-Schönbein GW. Proteolytic receptor cleavage in the pathogenesis of blood rheology and co-morbidities in metabolic syndrome. Early forms of autodigestion. Biorheology 2016; 52:337-52. [PMID: 26600265 DOI: 10.3233/bir-15045] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Abnormal blood rheological properties seldom occur in isolation and instead are accompanied by other complications, often designated as co-morbidities. In the metabolic syndrome with complications like hypertension, diabetes and lack of normal microvascular blood flow, the underlying molecular mechanisms that simultaneously lead to elevated blood pressure and diabetes as well as abnormal microvascular rheology and other cell dysfunctions have remained largely unknown. In this review, we propose a new hypothesis for the origin of abnormal cell functions as well as multiple co-morbidities. Utilizing experimental models for the metabolic disease with diverse co-morbidities we summarize evidence for the presence of an uncontrolled extracellular proteolytic activity that causes ectodomain receptor cleavage and loss of their associated cell function. We summarize evidence for unchecked degrading proteinase activity, e.g. due to matrix metalloproteases, in patients with hypertension, Type II diabetes and obesity, in addition to evidence for receptor cleavage in the form of receptor fragments and decreased extracellular membrane expression levels. The evidence suggest that a shift in blood rheological properties and other co-morbidities may in fact be derived from a common mechanism that is due to uncontrolled proteolytic activity, i.e. an early form of autodigestion. Identification of the particular proteases involved and the mechanisms of their activation may open the door to treatment that simultaneously targets multiple co-morbidities in the metabolic syndrome.
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Affiliation(s)
- Rafi Mazor
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Geert W Schmid-Schönbein
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA, USA
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Duansak N, Schmid-Schönbein GW. The oxygen free radicals control MMP-9 and transcription factors expression in the spontaneously hypertensive rat. Microvasc Res 2013; 90:154-61. [PMID: 24060804 DOI: 10.1016/j.mvr.2013.09.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 09/10/2013] [Accepted: 09/13/2013] [Indexed: 10/26/2022]
Abstract
Oxygen free radical and matrix metalloproteinases-9 (MMP-9) play an important pathophysiological role in the development of chronic hypertension. MMP-9 activities are regulated at different levels. We hypothesize that as mediators of the expression of MMP-9 the transcription factors like nuclear factor kappa B (NF-κB), c-fos and retinoic acid receptors-α (RAR-α) with binding sites to the MMP-9 promoter are overexpressed in the spontaneously hypertensive rat (SHR) in a process that is regulated by oxygen free radicals. Transcription factor NF-κB, c-fos and RAR-α expression levels were determined by immunohistochemistry in renal, cardiac and mesentery microcirculation of the SHR and its normotensive control, the Wistar Kyoto (WKY) rat. The animals were treated with a superoxide scavenger (Tempol) for eight weeks. The elevated plasma levels of thiobarbituric acid reactive substances and MMP-9 levels in the SHR were significantly decreased by Tempol treatment (P<0.05). The NF-κB, c-fos and RAR-α expression levels in renal glomerular, heart and mesentery microvessels were enhanced in the SHR and could also be reduced by Tempol compared to untreated animals (P<0.05). The enhanced MMP-9 levels in SHR microvessels co-express with transcription factors. These results suggest that elevated NF-κB, c-fos and RAR-α expressions and MMP-9 activity in the SHR are superoxide-dependent.
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Affiliation(s)
- Naphatsanan Duansak
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA 92093-0412, USA; Division of Physiology, Department of Preclinical Science, Faculty of Medicine, Thammasat University, Pathum Thani 12121, Thailand
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Schmid-Schönbein GW, Chang M. The autodigestion hypothesis for shock and multi-organ failure. Ann Biomed Eng 2013; 42:405-14. [PMID: 23989761 DOI: 10.1007/s10439-013-0891-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 08/09/2013] [Indexed: 01/20/2023]
Abstract
An important medical problem with high mortality is shock, sepsis and multi-organ failure. They have currently no treatments other than alleviation of symptoms. Shock is accompanied by strong markers for inflammation and involves a cascade of events that leads to failure in organs even if they are not involved in the initial insult. Recent evidence indicates that pancreatic digestive enzymes carried in the small intestine after mixing with ingested food are a major cause for multi-organ failure. These concentrated and relatively non-specific enzymes are usually compartmentalized inside the intestinal lumen as requirement for normal digestion. But after breakdown of the mucosal barrier they leak into the wall of the intestine and start an autodigestion process that includes destruction of villi in the intestine. Digestive enzymes also generate cytotoxic mediators, which together are transported into the systemic circulation via the portal venous system, the intestinal lymphatics and via the peritoneum. They cause various degrees of cell and organ dysfunction that can reach the point of complete organ failure. Blockade of digestive enzymes in the lumen of the intestine in experimental forms of shock serves to reduce breakdown of the mucosal barrier and autodigestion of the intestine, organ dysfunctions and mortality.
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Affiliation(s)
- Geert W Schmid-Schönbein
- Department of Bioengineering, The Institute of Engineering in Medicine, University of California San Diego, La Jolla, CA, 92093, USA,
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Palei ACT, Granger JP, Tanus-Santos JE. Matrix metalloproteinases as drug targets in preeclampsia. Curr Drug Targets 2013; 14:325-34. [PMID: 23316964 DOI: 10.2174/1389450111314030004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Revised: 12/10/2012] [Accepted: 01/01/2013] [Indexed: 11/22/2022]
Abstract
Preeclampsia is an important syndrome complicating pregnancy. While the pathogenesis of preeclampsia is not entirely known, poor placental perfusion leading to widespread maternal endothelial dysfunction is accepted as a major mechanism. It has been suggested that altered placental expression of matrix metalloproteinases (MMPs) may cause shallow cytotrophoblastic invasion and incomplete remodeling of the spiral arteries. MMPs are also thought to link placental ischemia to the cardiovascular alterations of preeclampsia. In fact, MMPs may promote vasoconstriction and surface receptors cleavage affecting the vasculature. Therefore, the overall goal of this review article is to provide an overview of the pathophisiology of preeclampsia, more specifically regarding the role of MMPs in the pathogenesis of preeclampsia and the potential of MMP inhibitors as therapeutic options.
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Affiliation(s)
- Ana C T Palei
- aDepartment of Physiology and Biophysics, School of Medicine, University of Mississippi Medical Center, 2500 North State St., Jackson, MS 39216, USA
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Stewart N, Chade AR. Renoprotective effects of hepatocyte growth factor in the stenotic kidney. Am J Physiol Renal Physiol 2012; 304:F625-33. [PMID: 23269649 DOI: 10.1152/ajprenal.00504.2012] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Renal microvascular (MV) damage and loss contribute to the progression of renal injury in renal artery stenosis (RAS). Hepatocyte growth factor (HGF) is a powerful angiogenic and antifibrotic cytokine that we showed to be decreased in the stenotic kidney. We hypothesized that renal HGF therapy will improve renal function mainly by protecting the renal microcirculation. Unilateral RAS was induced in 15 pigs. Six weeks later, single-kidney RBF and GFR were quantified in vivo using multidetector computed tomography (CT). Then, intrarenal rh-HGF or vehicle was randomly administered into the stenotic kidney (RAS, n = 8; RAS+HGF, n = 7). Pigs were observed for 4 additional weeks before CT studies were repeated. Renal MV density was quantified by 3D micro-CT ex vivo and histology, and expression of angiogenic and inflammatory factors, apoptosis, and fibrosis was determined. HGF therapy improved RBF and GFR compared with vehicle-treated pigs. This was accompanied by improved renal expression of angiogenic cytokines (VEGF, p-Akt) and tissue-healing promoters (SDF-1, CXCR4, MMP-9), reduced MV remodeling, apoptosis, and fibrosis, and attenuated renal inflammation. However, HGF therapy did not improve renal MV density, which was similarly reduced in RAS and RAS+HGF compared with controls. Using a clinically relevant animal model of RAS, we showed novel therapeutic effects of a targeted renal intervention. Our results show distinct actions on the existing renal microcirculation and promising renoprotective effects of HGF therapy in RAS. Furthermore, these effects imply plasticity of the stenotic kidney to recuperate its function and underscore the importance of MV integrity in the progression of renal injury in RAS.
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Affiliation(s)
- Nicholas Stewart
- Department of Physiology and Biophysics, Center for Excellence in Cardiovascular-Renal Research, University of Mississippi Medical Center, Jackson, MS 39216, USA
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13
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Frankwich K, Tibble C, Torres-Gonzalez M, Bonner M, Lefkowitz R, Tyndall M, Schmid-Schönbein GW, Villarreal F, Heller M, Herbst K. Proof of Concept: Matrix metalloproteinase inhibitor decreases inflammation and improves muscle insulin sensitivity in people with type 2 diabetes. JOURNAL OF INFLAMMATION-LONDON 2012; 9:35. [PMID: 23025537 PMCID: PMC3507843 DOI: 10.1186/1476-9255-9-35] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2012] [Accepted: 09/10/2012] [Indexed: 12/23/2022]
Abstract
Background Obesity is a state of subclinical inflammation resulting in loss of function of insulin receptors and decreased insulin sensitivity. Inhibition of the inflammatory enzymes, matrix metalloproteinases (MMPs), for 6 months in rodent models restores insulin receptor function and insulin sensitivity. Methods This 12-week double-blind, randomized, placebo (PL)-controlled proof-of-concept study was performed to determine if the MMP inhibitor (MMPI), doxycycline, decreased global markers of inflammation and enhanced muscle insulin sensitivity in obese people with type 2 diabetes (DM2). The study included non-DM2 controls (n = 15), and DM2 subjects randomized to PL (n = 13) or doxycycline 100 mg twice daily (MMPI; n = 11). All participants were evaluated on Day 1; MMPI and PL groups were also evaluated after 84 days of treatment. Results There was a significant decrease in inflammatory markers C-reactive protein (P < 0.05) and myeloperoxidase (P = 0.01) in the MMPI but not PL group. The MMPI also significantly increased skeletal muscle activated/total insulin signaling mediators: 3’phosphoinositide kinase-1 (PDK1) (p < 0.03), protein kinase B (PKB/Akt) (p < 0.004), and glycogen synthase kinase 3ß (GSK3ß) (p < 0.03). Conclusions This study demonstrated short term treatment of people with diabetes with an MMPI resulted in decreased inflammation and improved insulin sensitivity. Larger, longer studies are warranted to determine if doxycycline can improve glucose control in people with diabetes. Trial Registration Clinicaltrials.gov NCT01375491
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Affiliation(s)
- Karen Frankwich
- Veteran's Affairs, San Diego Healthcare System, 3350 La Jolla Village Drive (111 G), San Diego, CA, 92161, USA.
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Yang M, Murfee WL. The effect of microvascular pattern alterations on network resistance in spontaneously hypertensive rats. Med Biol Eng Comput 2012; 50:585-93. [PMID: 22562369 DOI: 10.1007/s11517-012-0912-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 04/25/2012] [Indexed: 12/31/2022]
Abstract
Structural microvascular rarefaction, defined by a loss of vessels, is a common characteristic of hypertension and has been associated with elevated microvascular resistance. However, determining the causal relationship between microvascular network structure and resistance requires a consideration of all pattern changes throughout a network. The objectives of this study were to determine whether microvascular rarefaction is associated with other network pattern alterations and to evaluate whether pattern alterations in hypertension necessarily contribute to increased microvascular resistance. Mesenteric tissues from age-matched (15-16 weeks) male spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were harvested and immunolabeled for PECAM. SHR networks displayed a decreased microvascular area, arteriolar-venular (AV) length, number of AV branches, and number of capillary segments. In addition, SHR networks displayed increased AV connections per network compared to WKY networks. Based on network geometries, resistance per network was calculated using a computational model. For simulations with equal vessel diameter and with relative diameters based on reported intravital measurements, SHR microvascular network resistance was not elevated compared to the WKY level. Our results suggest that microvascular pattern alterations associated with hypertension are more complex than vessel loss, and that these combined alterations do not necessarily lead to elevated resistance.
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Affiliation(s)
- Ming Yang
- Department of Biomedical Engineering, Tulane University, New Orleans, LA 70118, USA
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15
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Schmid-Schönbein GW. An emerging role of degrading proteinases in hypertension and the metabolic syndrome: autodigestion and receptor cleavage. Curr Hypertens Rep 2012; 14:88-96. [PMID: 22081429 DOI: 10.1007/s11906-011-0240-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
One of the major challenges for hypertension research is to identify the mechanisms that cause the comorbidities encountered in many hypertensive patients, as seen in the metabolic syndrome. An emerging body of evidence suggests that human and experimental hypertensives may exhibit uncontrolled activity of proteinases, including the family of matrix metalloproteinases, recognized for their ability to restructure the extracellular matrix proteins and to play a role in hypertrophy. We propose a new hypothesis that provides a molecular framework for the comorbidities of hypertension, diabetes, capillary rarefaction, immune suppression, and other cell and organ dysfunctions due to early and uncontrolled extracellular receptor cleavage by active proteinases. The proteinase and signaling activity in hypertensives requires further detailed analysis of the proteinase expression, the mechanisms causing proenzyme activation, and identification of the proteinase substrate. This work may open the opportunity for reassessment of old interventions and development of new interventions to manage hypertension and its comorbidities.
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Affiliation(s)
- Geert W Schmid-Schönbein
- Department of Bioengineering, Institute of Engineering in Medicine, University of California San Diego, La Jolla, CA 92093-0412, USA.
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Delano FA, Chen AY, Wu KIS, Tran ED, Rodrigues SF, Schmid-Schönbein GW. THE AUTODIGESTION HYPOTHESIS AND RECEPTOR CLEAVAGE IN DIABETES AND HYPERTENSION. ACTA ACUST UNITED AC 2011; 8:37-46. [PMID: 22081770 DOI: 10.1016/j.ddmod.2011.05.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
One of the key features of cardiovascular complications, such as hypertension or diabetes, is that they often appear at the same time in the same individual together with other forms of co-morbidities. While clinically a recognized phenomenon, no molecular mechanism for such co-morbidities has received universal acceptance. We propose a new hypothesis that provides a molecular basis for co-morbidities in hypertension due to unchecked proteolytic activity and receptor destruction. Testing of the hypothesis in the spontaneously hypertensive rat reveals an unchecked matrix metalloproteinase and serine protease activity in plasma and on several cardiovascular and parenchymal cells. The elevated proteolytic activity causes extracellular cleavage of multiple receptor types, such that cleavage of one receptor type leads to loss of the function carried out by this receptor. Proteolytic cleavage of the extracellular domain of the β(2) adrenergic receptor in arteries and arterioles causes vasoconstriction and elevation of the central blood pressure while cleavage of the extracellular domain of the insulin receptor leads to insulin resistance and lack of transmembrane glucose transport. A diverse set of cell dysfunctions in the spontaneously hypertensive rat are accompanied by cleavage of the membrane receptors that are involved in these functions. Chronic inhibition of the unchecked protease activity in the spontaneously hypertensive rat serves to restore the extracellular receptor density and alleviates the corresponding cell dysfunctions. The mild unchecked proteolytic activity in the spontaneously hypertensive rat points towards a chronic autodigestion process as a contributor to the end organ injury encountered in this rat strain. The presence of various soluble receptors, which consist of extracellular fragments of membrane receptors, in the plasma of hypertensive and diabetic patients suggest that the autodigestion process may also be present in man.
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Affiliation(s)
- F A Delano
- Department of Bioengineering, Institute for Engineering in Medicine, University of California San Diego, La Jolla, CA 92093 - 0412
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