Blood-borne collagenous debris complexes with plasma fibronectin after thermal injury

Abstract Plasma fibronectin augments the clearance of blood-borne foreign and effete complexes by mononuclear phagocytes. The release of a “gelatin- like” ligand into plasma after thermal injury has been reported. We quantified the release of this collagenous debris from thermally injured skin, and its potential interaction with soluble fibronectin in plasma using anesthetized rats. Collagen-like material debris in the plasma was detected by assay of hydroxyproline. Fibronectin was measured by a double antibody enzyme-linked immunosorbent assay (ELISA) technique. Over a 24-hour postburn interval, plasma hydroxyproline increased from 6.7 +/- 0.6 micrograms/mL to a maximum of 19.0 +/- 3.3 micrograms/mL at 60 minutes postburn, and normalized by 6 hours. A direct correlation existed between the magnitude of burn injury and the increase in plasma hydroxyproline. In parallel, plasma fibronectin declined over a 15-minute to 2-hour period postburn, and normalized by 3 to 4 hours with rebound hyperfibronectinemia observed at 24 hours. The elevation in total plasma hydroxyproline was not due to an increase in plasma Clq (zero time, 26.2 +/- 1.4 micrograms/mL; 60 minutes, 23.9 +/- 1.1 micrograms/mL). Tracer studies with 125I-fibronectin showed that the acute decline of plasma fibronectin was due to its uptake by the liver and binding to sites of tissue injury. Total hydroxyproline in extracts of burn skin, used as an index of soluble collagenous material, rose from 15 +/- 3.3 micrograms/g skin at zero time to 129.3 +/- 43.7 micrograms/g skin by 5 minutes postburn, with a decline to 38 +/- 22 micrograms/g skin by 24 hours. The formation of circulating fibronectin-gelatin complexes in vivo was documented by cross- immunoelectrophoresis coupled with autoradiography using 125I-gelatin as a model ligand. Thus, collagenous tissue debris from burned skin may enter the plasma after thermal injury and directly complexes with soluble fibronectin before hepatic phagocytic clearance.

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Blood-borne collagenous debris complexes with plasma fibronectin after thermal injury

Blood ◽

10.1182/blood.v75.2.470.bloodjournal752470 ◽

1990 ◽

Vol 75 (2) ◽

pp. 470-478

Author(s):

P La Celle ◽

FA Blumenstock ◽

C McKinley ◽

TM Saba ◽

PA Vincent ◽

...

Keyword(s):

Thermal Injury ◽

Burn Injury ◽

Tissue Injury ◽

Potential Interaction ◽

Mononuclear Phagocytes ◽

Enzyme Linked Immunosorbent Assay ◽

Plasma Fibronectin ◽

Collagenous Tissue ◽

Zero Time

Plasma fibronectin augments the clearance of blood-borne foreign and effete complexes by mononuclear phagocytes. The release of a “gelatin- like” ligand into plasma after thermal injury has been reported. We quantified the release of this collagenous debris from thermally injured skin, and its potential interaction with soluble fibronectin in plasma using anesthetized rats. Collagen-like material debris in the plasma was detected by assay of hydroxyproline. Fibronectin was measured by a double antibody enzyme-linked immunosorbent assay (ELISA) technique. Over a 24-hour postburn interval, plasma hydroxyproline increased from 6.7 +/- 0.6 micrograms/mL to a maximum of 19.0 +/- 3.3 micrograms/mL at 60 minutes postburn, and normalized by 6 hours. A direct correlation existed between the magnitude of burn injury and the increase in plasma hydroxyproline. In parallel, plasma fibronectin declined over a 15-minute to 2-hour period postburn, and normalized by 3 to 4 hours with rebound hyperfibronectinemia observed at 24 hours. The elevation in total plasma hydroxyproline was not due to an increase in plasma Clq (zero time, 26.2 +/- 1.4 micrograms/mL; 60 minutes, 23.9 +/- 1.1 micrograms/mL). Tracer studies with 125I-fibronectin showed that the acute decline of plasma fibronectin was due to its uptake by the liver and binding to sites of tissue injury. Total hydroxyproline in extracts of burn skin, used as an index of soluble collagenous material, rose from 15 +/- 3.3 micrograms/g skin at zero time to 129.3 +/- 43.7 micrograms/g skin by 5 minutes postburn, with a decline to 38 +/- 22 micrograms/g skin by 24 hours. The formation of circulating fibronectin-gelatin complexes in vivo was documented by cross- immunoelectrophoresis coupled with autoradiography using 125I-gelatin as a model ligand. Thus, collagenous tissue debris from burned skin may enter the plasma after thermal injury and directly complexes with soluble fibronectin before hepatic phagocytic clearance.

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Blood-borne fragments of fibronectin after thermal injury

Blood ◽

10.1182/blood.v77.9.2037.2037 ◽

1991 ◽

Vol 77 (9) ◽

pp. 2037-2041 ◽

Cited By ~ 5

Author(s):

P La Celle ◽

FA Blumenstock ◽

TM Saba

Keyword(s):

Thermal Injury ◽

Proteolytic Enzymes ◽

Tissue Injury ◽

Plasma Concentrations ◽

Vena Cava ◽

Enzyme Linked Immunosorbent Assay ◽

Plasma Fibronectin ◽

Opsonic Activity ◽

Macrophage Phagocytosis ◽

Fibronectin Fragments

Abstract Fibronectin is an adhesive protein that can promote phagocytosis and endothelial cell adhesion. Plasma fibronectin declines following burn in animals and patients, potentially due to its complexing with circulating collagenous debris as well as its rapid binding to sites of tissue injury. Such depletion of fibronectin initiates an opsonic deficiency of the plasma. In view of the sensitivity of fibronectin to proteolytic enzymes, an additional factor that could contribute to the decrease of plasma opsonic activity after burn is the proteolytic fragmentation of fibronectin in the blood. In the current study, we determined if fibronectin fragments appear in the blood of anesthetized rats after a sublethal full-thickness skin burn of 15% to 16% of body surface. Plasma fibronectin concentration was quantified by enzyme- linked immunosorbent assay and the presence of fibronectin fragments in plasma was determined by immunoblot analysis. All blood was collected in an antiprotease mixture to yield final plasma concentrations of 0.15% EDTA, 3mmol/L phenylmethylsulfonyl fluoride, and 3 mmol/L iodoacetate to prevent degradation of fibronectin after sampling. Plasma fibronectin decreased 60% to 70% within 30 minutes post-burn, and this low level lasted for at least 4 hours. Within 30 minutes post- burn, two prominent fragments of fibronectin with a molecular weight of 110 +/- 2.2 kd and 122 +/- 3.3 Kd, respectively, were also detected in the plasma. Peak concentration of these fragments was detected at 60 minutes post-burn, but their level declined by 4 hours. By 4 hours, both bands appeared to resolve into doublets. To rule out the possibility that the fragments of fibronectin detected in the plasma were actually generated by coagulation enzymes activated at the site of peripheral blood sampling, rapid direct inferior vena cava sampling was performed, which also yield the presence of the fragments. Thus, fibronectin fragments exist in the plasma following thermal injury. Because fragments of fibronectin can compete with the intact fibronectin molecule with respect to its ability to stimulate macrophage phagocytosis, such fragments may contribute to altered systemic phagocytic host defense following thermal injury. Furthermore, because fibronectin peptides can compete with matrix fibronectin and impair adhesion of cultured endothelial cells, such circulating fragments may also influence the integrity of the vascular barrier.

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Blood-borne fragments of fibronectin after thermal injury

Blood ◽

10.1182/blood.v77.9.2037.bloodjournal7792037 ◽

1991 ◽

Vol 77 (9) ◽

pp. 2037-2041

Author(s):

P La Celle ◽

FA Blumenstock ◽

TM Saba

Keyword(s):

Thermal Injury ◽

Proteolytic Enzymes ◽

Tissue Injury ◽

Plasma Concentrations ◽

Vena Cava ◽

Enzyme Linked Immunosorbent Assay ◽

Plasma Fibronectin ◽

Opsonic Activity ◽

Macrophage Phagocytosis ◽

Fibronectin Fragments

Fibronectin is an adhesive protein that can promote phagocytosis and endothelial cell adhesion. Plasma fibronectin declines following burn in animals and patients, potentially due to its complexing with circulating collagenous debris as well as its rapid binding to sites of tissue injury. Such depletion of fibronectin initiates an opsonic deficiency of the plasma. In view of the sensitivity of fibronectin to proteolytic enzymes, an additional factor that could contribute to the decrease of plasma opsonic activity after burn is the proteolytic fragmentation of fibronectin in the blood. In the current study, we determined if fibronectin fragments appear in the blood of anesthetized rats after a sublethal full-thickness skin burn of 15% to 16% of body surface. Plasma fibronectin concentration was quantified by enzyme- linked immunosorbent assay and the presence of fibronectin fragments in plasma was determined by immunoblot analysis. All blood was collected in an antiprotease mixture to yield final plasma concentrations of 0.15% EDTA, 3mmol/L phenylmethylsulfonyl fluoride, and 3 mmol/L iodoacetate to prevent degradation of fibronectin after sampling. Plasma fibronectin decreased 60% to 70% within 30 minutes post-burn, and this low level lasted for at least 4 hours. Within 30 minutes post- burn, two prominent fragments of fibronectin with a molecular weight of 110 +/- 2.2 kd and 122 +/- 3.3 Kd, respectively, were also detected in the plasma. Peak concentration of these fragments was detected at 60 minutes post-burn, but their level declined by 4 hours. By 4 hours, both bands appeared to resolve into doublets. To rule out the possibility that the fragments of fibronectin detected in the plasma were actually generated by coagulation enzymes activated at the site of peripheral blood sampling, rapid direct inferior vena cava sampling was performed, which also yield the presence of the fragments. Thus, fibronectin fragments exist in the plasma following thermal injury. Because fragments of fibronectin can compete with the intact fibronectin molecule with respect to its ability to stimulate macrophage phagocytosis, such fragments may contribute to altered systemic phagocytic host defense following thermal injury. Furthermore, because fibronectin peptides can compete with matrix fibronectin and impair adhesion of cultured endothelial cells, such circulating fragments may also influence the integrity of the vascular barrier.

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Burn-induced increase in atrogin-1 and MuRF-1 in skeletal muscle is glucocorticoid independent but downregulated by IGF-I

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00561.2006 ◽

2007 ◽

Vol 292 (1) ◽

pp. R328-R336 ◽

Cited By ~ 62

Author(s):

Charles H. Lang ◽

Danuta Huber ◽

Robert A. Frost

Keyword(s):

Thermal Injury ◽

Burn Injury ◽

Total Body Surface Area ◽

Ring Finger ◽

E3 Ligase ◽

E3 Ligases ◽

Igf I ◽

Mrna Content ◽

Total Body

The present study determined whether thermal injury increases the expression of the ubiquitin (Ub) E3 ligases referred to as muscle ring finger (MuRF)-1 and muscle atrophy F-box (MAFbx; aka atrogin-1), which are muscle specific and responsible for the increased protein breakdown observed in other catabolic conditions. After 48 h of burn injury (40% total body surface area full-thickness scald burn) gastrocnemius weight was reduced, and this change was associated with an increased mRNA abundance for atrogin-1 and MuRF-1 (3.1- to 8-fold, respectively). Similarly, burn increased polyUb mRNA content in the gastrocnemius twofold. In contrast, there was no burn-induced atrophy of the soleus and no significant change in atrogin-1, MuRF-1, or polyUb mRNA. Burns also did not alter E3 ligase expression in heart. Four hours after administration of the anabolic agent insulin-like growth factor (IGF)-I to burned rats, the mRNA content of atrogin-1 and polyUb in gastrocnemius had returned to control values and the elevation in MuRF-1 was reduced 50%. In contrast, leucine did not alter E3 ligase expression. In a separate study, in vivo administration of the proteasome inhibitor Velcade prevented burn-induced loss of muscle mass determined at 48 h. Finally, administration of the glucocorticoid receptor antagonist RU-486 did not prevent burn-induced atrophy of the gastrocnemius or the associated elevation in atrogin-1, MuRF-1, or polyUb. In summary, the acute muscle wasting accompanying thermal injury is associated with a glucocorticoid-independent increase in the expression of several Ub E3 ligases that can be downregulated by IGF-I.

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Inflammatory events drive neural stem cell migration by elevating stromal-derived factor 1 alpha

STEMedicine ◽

10.37175/stemedicine.v1i3.59 ◽

2020 ◽

Vol 1 (3) ◽

pp. e59

Author(s):

Ziyun Jiang ◽

Mingliang Tang

Keyword(s):

Stem Cell ◽

Neural Stem Cell ◽

Microglial Activation ◽

Brain Injuries ◽

Glucose Deprivation ◽

Potential Interaction ◽

Enzyme Linked Immunosorbent Assay ◽

Migration Assay

Background: Ischemic stroke is the most common cause of ischemia-related death globally. Brain injuries due to stroke and trauma are typically followed by inflammation reactions within the central nervous system (CNS). Neural stem cell (NSC)-based therapeutic strategies show great potential for treating stroke and ischemia-mediated brain injuries, and migration of NSCs is a critical step involved in NSC-based therapy. Methods: In order to examine the effects of microglial activation upon ischemia and stroke on NSC behaviors, oxygen-glucose deprivation (OGD) in vitro model was established for mimicking in vivo stroke and ischemia pathological conditions in this study. By combining of enzyme-linked immunosorbent assay, migration assay, Western blot and immunostaining, we found that OGD insult induced microglial activation by releasing cytokines and chemokines. Results: The conditioned media (CM) of OGD-treated groups impaired the proliferation and capability of neurosphere formation. Moreover, we found the stromal cell-derived factor 1α/CXC chemokine receptor 4 (CXCR4) pathway was an active player that facilitated the migration of NSCs, since a CXCR4 specific antagonist AMD3100 was able to impair NSC migration both in vitro and in vivo. Conclusion: The current study presents a potential interaction between NSC behaviors and microglial activation underlying brain injuries, such as ischemia and stroke. More importantly, we reveal the underlying mechanisms of microglia-induced NSC migration under OGD conditions and it should be beneficial to stem cell-based therapies to treat acute brain injuries.

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L-arginine suppresses lipopolysaccharide-induced expression of RANTES in glomeruli.

Journal of the American Society of Nephrology ◽

10.1681/asn.v92203 ◽

1998 ◽

Vol 9 (2) ◽

pp. 203-210 ◽

Cited By ~ 1

Author(s):

U Haberstroh ◽

K Stilo ◽

J Pocock ◽

G Wolf ◽

U Helmchen ◽

...

Keyword(s):

Mrna Expression ◽

Tissue Injury ◽

Inflammatory Cells ◽

Northern Blotting ◽

No Synthase ◽

In Vivo Model ◽

Enzyme Linked Immunosorbent Assay ◽

Inflammatory Cell Infiltrate ◽

Beneficial Effects

Endotoxemia leads to the infiltration of inflammatory cells in glomeruli and the tubulointerstitium of the kidney. The ultimate mechanisms for this infiltration, however, are not entirely clear. In this study, the glomerular formation of the chemokine RANTES (regulated upon activation normal T cell expressed and secreted) was examined in an in vivo model of endotoxemia to evaluate the role the local release of chemokines might play in the regulation of this inflammatory cell infiltrate. Since the beneficial effects of nitric oxide (NO) on immune-mediated tissue injury have been reported, we also examined possible interactions between the chemokine RANTES and the L-arginine/NO pathway. To induce endotoxemia, rats were injected intraperitoneally with lipopolysaccharide (LPS). Glomeruli were isolated over a 24-h time period, and RANTES was assessed by Northern blotting, a chemotactic assay, and a specific enzyme-linked immunosorbent assay. The chemokine release was associated with increased glomerular infiltration of monocytes/macrophages. LPS also stimulated the mRNA expression of inducible NO synthase and increased the release of nitrite into the supernatants of isolated glomeruli. Supplementation of L-arginine intake increased the release of glomerular nitrite and reduced glomerular RANTES expression after the injection of LPS. Inhibition of the L-arginine/NO pathway by the unspecific NO synthase inhibitor N(G)-nitro-L-arginine methylester significantly increased glomerular RANTES mRNA expression and the number of infiltrating glomerular macrophages. These data demonstrate that L-arginine suppresses glomerular RANTES formation and suggest that the chemokine-mediated recruitment of glomerular macrophages in LPS-induced endotoxemia can be modulated by the L-arginine/NO pathway.

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Gelsolin expression in liver, spleen and blood plasma provides insights into its function in mice following acute insults

European Journal of Inflammation ◽

10.1177/1721727x16678005 ◽

2016 ◽

Vol 14 (3) ◽

pp. 162-168

Author(s):

Haiyan Fu ◽

Hongyang Du ◽

Zhansheng Hu ◽

Xiudong Ying ◽

Rongbin Zhou

Keyword(s):

Blood Serum ◽

Messenger Rna ◽

Thermal Injury ◽

Burn Injury ◽

Quantitative Polymerase Chain Reaction ◽

Actin Binding ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

Polymerase Chain ◽

Binding Plasma Protein

Background: Gelsolin (GSN) is an actin-binding plasma protein with a pivotal role in the systemic response to acute tissue damage. The present study investigated GSN expression in the liver, spleen and blood serum in mice after burn. Method: A murine model of thermal injury was selected, and the animals were sacrificed at 8, 24, 48 and 72 h after injury. Real-time quantitative polymerase chain reaction (RT-PCR) was performed to determine the messenger RNA (mRNA) expression of GSN, and GSN protein expression was determined by enzyme-linked immunosorbent assay (ELISA). Results: We found that GSN mRNA and protein were expressed in the liver, spleen and blood serum of the mice. GSN expression in these tissues was the lowest among the tested time points at 8 h after burn injury. The mortality within 72 h among the mice subjected to burn injury was significantly lower in those treated with GSN than in those not treated with GSN. Treatment with GSN markedly increased the GSN levels in the liver, spleen and blood serum after injury. Conclusion: These results indicated that GSN treatment may affect the outcome of thermal injury via changes in the GSN content of multiple tissues.

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Tissues Use Resident Dendritic Cells and Macrophages to Maintain Homeostasis and to Regain Homeostasis upon Tissue Injury: The Immunoregulatory Role of Changing Tissue Environments

Mediators of Inflammation ◽

10.1155/2012/951390 ◽

2012 ◽

Vol 2012 ◽

pp. 1-15 ◽

Cited By ~ 41

Author(s):

Maciej Lech ◽

Regina Gröbmayr ◽

Marc Weidenbusch ◽

Hans-Joachim Anders

Keyword(s):

Dendritic Cells ◽

Host Defense ◽

Complex Disease ◽

Tissue Injury ◽

Data Interpretation ◽

Mononuclear Phagocytes ◽

Temporal And Spatial ◽

Pathogen Clearance

Most tissues harbor resident mononuclear phagocytes, that is, dendritic cells and macrophages. A classification that sufficiently covers their phenotypic heterogeneity and plasticity during homeostasis and disease does not yet exist because cell culture-based phenotypes often do not match those foundin vivo. The plasticity of mononuclear phagocytes becomes obvious during dynamic or complex disease processes. Different data interpretation also originates from different conceptual perspectives. An immune-centric view assumes that a particular priming of phagocytes then causes a particular type of pathology in target tissues, conceptually similar to antigen-specific T-cell priming. A tissue-centric view assumes that changing tissue microenvironments shape the phenotypes of their resident and infiltrating mononuclear phagocytes to fulfill the tissue's need to maintain or regain homeostasis. Here we discuss the latter concept, for example, why different organs host different types of mononuclear phagocytes during homeostasis. We further discuss how injuries alter tissue environments and how this primes mononuclear phagocytes to enforce this particular environment, for example, to support host defense and pathogen clearance, to support the resolution of inflammation, to support epithelial and mesenchymal healing, and to support the resolution of fibrosis to the smallest possible scar. Thus, organ- and disease phase-specific microenvironments determine macrophage and dendritic cell heterogeneity in a temporal and spatial manner, which assures their support to maintain and regain homeostasis in whatever condition. Mononuclear phagocytes contributions to tissue pathologies relate to their central roles in orchestrating all stages of host defense and wound healing, which often become maladaptive processes, especially in sterile and/or diffuse tissue injuries.

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In vivo studies of cellular energy state, pH, and sodium in rat liver after thermal injury

Journal of Applied Physiology ◽

10.1152/jappl.1994.76.4.1507 ◽

1994 ◽

Vol 76 (4) ◽

pp. 1507-1511 ◽

Cited By ~ 16

Author(s):

Z. F. Xia ◽

J. W. Horton ◽

P. Y. Zhao ◽

N. Bansal ◽

E. E. Babcock ◽

...

Keyword(s):

Magnetic Resonance ◽

Magnetic Resonance Spectroscopy ◽

Intracellular Ph ◽

Thermal Injury ◽

Burn Injury ◽

Total Body Surface Area ◽

In Vivo Studies ◽

Resonance Spectroscopy ◽

Major Burn

In vivo 31P- and 23Na-magnetic resonance spectroscopy was used to measure phosphorus metabolites, intracellular pH, cytosolic free Mg2+, and intracellular Na+ in the liver of rats 24 h after 40% total body surface area full-thickness burn injury. Studies were performed during infusion of thulium (III) 1,4,7,10-tetraazacyclododecane N,N′,N″,N″′-tetra(methylenephosphonate), which served as the Na+ shift agent. Compared with the sham-burn group, there was a significant increase in hepatic intracellular Na+ along with a decrease in intracellular pH and free Mg2+. The ratio of intra- to extra-cellular Na+ increased, indicating a decreased Na+ gradient that may determine the hepatic transmembrane potential difference. Hepatic beta-ATP/P(i) also significantly decreased, which suggests that either ATP utilization is significantly accelerated or ATP synthesis is inhibited after the thermal injury. Of the cations measured (Na+, Mg2+, H+), the change in intracellular Na+ was most dramatic. This study demonstrates that major burn injury may cause profound changes in hepatic bioenergetics and ionic metabolism 24 h after injury and that intracellular Na+ may be a sensitive indicator of hepatic dysfunction 24 h after injury. Because these animals tolerated the shift reagent, thuliumIII) 1,4,7,10-tetraazacyclododecane N,N′,N″,N″′-tetra(methylenephosphonate), nuclear magnetic resonance spectroscopy may prove valuable in monitoring intracellular cations in the liver after major injury.

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