SOCS2 Silencing Improves Somatic Growth without Worsening Kidney Function in CKD

2020 ◽  
Vol 51 (7) ◽  
pp. 520-526
Author(s):  
Daniel Landau ◽  
Muhammad H. Assadi ◽  
Rawan Abu Hilal ◽  
Yu Chen ◽  
Ralph Rabkin ◽  
...  
Keyword(s):  
Somatic Growth ◽  
High Growth ◽  
Body Growth ◽  
Negative Regulator ◽  
Collagen Type Iv ◽  
Sham Operation ◽  
Type Iv ◽  
Intracellular Signal ◽  
Socs3 Mrna ◽  
Gh Resistance

Background: Growth hormone (GH) resistance in CKD is partly due to increased expression of SOCS2, a GH signaling negative regulator. In SOCS2 absence, body growth is exaggerated. However, GH overexpression in mice causes glomerulosclerosis. Accordingly, we tested whether lack of SOCS2 improves body growth, but accelerates kidney damage in CKD. Methods: Eight-week-old mutant SOCS2-deficient high growth (HG) and normal wild-type mice (N) underwent 5/6 nephrectomy (CKD) or sham operation (C) and were sacrificed after 12 weeks, generating 4 groups: C-N, C-HG, CKD-N, CKD-HG. Results: Somatic growth, inhibited in CKD-N, increased significantly in CKD-HG. Liver p-STAT5, a key intracellular signal of GH receptor (GHR) activation, was decreased in CKD-N but not in CKD-HG. Serum Cr as well as histopathological scores of renal fibrosis were similar in both CKD groups. Kidney fibrogenic (TGF-β and collagen type IV mRNA) and inflammatory precursors (IL6, STAT3, and SOCS3 mRNA) were similarly increased in C-HG, CKD-HG, and CKD-N versus C-N. Renal GHR mRNA was decreased in C-HG, CKD-HG, and CKD-N versus C-N. Kidney p-STAT5 was decreased in CKD-N but not elevated in CKD-HG. Conclusions: CKD-related growth retardation is overcome by SOCS2 silencing, in association with increased hepatic STAT5 phosphorylation. Renal insufficiency is not worsened by SOCS2 absence, as kidney GHR and STAT5 are not upregulated. This may be due to elevated kidney proinflammatory cytokines and their mediators, phospho-STAT3 and SOCS3, which may counteract for the absence in SOCS2 and explain the renal safety of prolonged GH therapy in CKD.

The use of 1nm silver enhanced gold probes for the detection of skin antigens

1990 ◽  
Vol 48 (3) ◽  
pp. 902-903
Author(s):  
J.P Cassella ◽  
H. Shimizu ◽  
A. Ishida-Yamamoto ◽  
R.A.J. Eady
Keyword(s):  
Type Iv Collagen ◽  
Freeze Substitution ◽  
Collagen Type Iv ◽  
Electron Microscopic ◽  
Normal Human Skin ◽  
Type Iv ◽  
Type Vii Collagen ◽  
Keratin Filaments ◽  
Normal Human ◽  
Phosphate Buffered Saline

1nm colloidal gold with silver enhancement has been used in conjunction with a low-temperature post-embedding (post-E) technique for the demonstration of skin antigens at both the light microscopic (LM) and electron microscopic (EM) levels.Keratin filaments and basement membrane zone (BMZ) associated antigens in normal human skin (NHS) were immunolabelled using antibodies against keratin 14, 10, and 1, the carboxy-terminus and collagenous portion of type VII collagen, type IV collagen and bullous pemphigoid antigen (BP-Ag).Fresh samples of NHS were cryoprotected in 15% glycerol, cryofixed in propane at -190°C, subjected to freeze substitution in methanol at -80°C and embedded in Lowicryl K11M at -60°C. Polymerisation of the resin was initiated under UVR at - 60°C for 48 hours and continued at room temperature for a further 48 hours. Semith in sections were air dried onto slides coated with 3-aminopropyltriethoxysilane. The following immunolabelling protocol was adopted: Primary antibody was applied for 2 hours at 37°C or overnight at 4°C. Following washing in Dulbecco’s phosphate buffered saline (PBSA) a biotinylated secondary antibody was applied for 2 hours at 37°C. The sections were further washed in PBSA and 1nm gold avidin was applied. Sections were finally washed in PBSA and silver enhanced.

scholarly journals Serum Anti-Collagen IV IgM and IgG Antibodies as Indicators of Low Vascular Turnover of Collagen IV in Patients with Long-Term Complications of Type 2 Diabetes

Diagnostics ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 900
Author(s):  
Krasimir Kostov ◽  
Alexander Blazhev
Keyword(s):  
Type 2 Diabetes ◽  
Serum Levels ◽  
Vascular Wall ◽  
Collagen Iv ◽  
Collagen Type Iv ◽  
Non Invasive ◽  
Type Iv ◽  
Antibody Levels

Thickening of the vascular basement membrane (BM) is a fundamental structural change in the small blood vessels in diabetes. Collagen type IV (CIV) is a major component of the BMs, and monitoring the turnover of this protein in type 2 diabetes (T2D) can provide important information about the mechanisms of vascular damage. The aim of the study was through the use of non-invasive biomarkers of CIV (autoantibodies, derivative peptides, and immune complexes) to investigate vascular turnover of CIV in patients with long-term complications of T2D. We measured serum levels of these biomarkers in 59 T2D patients with micro- and/or macrovascular complications and 20 healthy controls using an ELISA. Matrix metalloproteinases-2 and -9 (MMP-2 and MMP-9) were also tested. In the T2D group, significantly lower levels of CIV markers and significantly higher levels of MMP-2 and MMP-9 were found compared to controls. A significant positive correlation was found between IgM antibody levels against CIV and MMP-2. These findings suggest that vascular metabolism of CIV is decreased in T2D with long-term complications and show that a positive linear relationship exists between MMP-2 levels and CIV turnover in the vascular wall.

Release of collagen type IV degrading activity from C6 astrocytoma cells and cell density

1996 ◽  
Vol 84 (6) ◽  
pp. 1013-1019 ◽  
Author(s):  
Masashi Tamaki ◽  
Warren McDonald ◽  
Rolando F. Del Maestro
Keyword(s):  
Cell Density ◽  
Collagen Type ◽  
Cell Communication ◽  
Collagen Type Iv ◽  
Major Protein ◽  
Content Type ◽  
Type Iv ◽  
Astrocytoma Cells ◽  
C6 Astrocytoma

✓ Type IV collagen is a major protein component of the vascular basement membrane and its degradation is crucial to the initiation of tumor-associated angiogenesis. The authors have investigated the influence of cell density on the release of collagen type IV degrading activity by C6 astrocytoma cells in monolayer culture. The release of collagen type IV degrading activity was assessed biochemically, immunocytochemically, and by Western blot analysis. The results demonstrate that increasing plating density and increasing cell density are associated with decreased collagen type IV degrading activity released per tumor cell. These findings indicate the existence of regulatory mechanisms dependent on cell—cell communication, which modulate release of collagen type IV degrading activity. The extrapolation of these results to the in vivo tumor microenvironment would suggest that individual and/or small groups of invading tumor cells, distant from the main tumor mass, would release substantial collagen type IV degrading activity, which may be crucial to their continued invasion and to angiogenesis.

Collagen type IV in acute rejection of kidney

2000 ◽  
Vol 32 (7) ◽  
pp. 1785 ◽  
Author(s):  
K Utsumi ◽  
T Sawada ◽  
E Adachi ◽  
S Horita ◽  
T Tojimbara ◽  
...  
Keyword(s):  
Acute Rejection ◽  
Collagen Type ◽  
Collagen Type Iv ◽  
Type Iv

EOSINOPHILIC GASTRITIS IN CHILDREN: MORPHOLOGICAL AND IMMUNOHISTOCHEMICAL DIAGNOSTIC CRITERIA

2021 ◽  
Vol 74 (7) ◽  
pp. 1722-1727
Author(s):  
Vira I. Bobrova ◽  
Anastasia O. Horobets ◽  
Julia I. Proshchenko ◽  
Ludmila O. Levadna ◽  
Zoriana V. Selska
Keyword(s):  
Lamina Propria ◽  
Collagen Type ◽  
Morphological Changes ◽  
Prognostic Index ◽  
Lymphocytic Infiltration ◽  
Eosinophilic Infiltration ◽  
Nuclear Antigen ◽  
Collagen Type Iv ◽  
Eosinophilic Gastritis ◽  
Type Iv

The aim: To study peculiarities of morphological and immunohistochemical changes of stomach’s mucosa in eosinophilic gastritis in children Materials and methods: 64.1±6.0% patients with eosinophilic gastritis and 35.9±6.0% patients with lymphocytic gastritis participated in our investigation. In order to verify the diagnosis morphological and immunohistochemical diagnostics of the stomach’s mucosa was performed in all children. To assess morphological changes in tissues the specimens were colored with hematoxylin, eosin and picrofuchsin by van Gieson’s. Indirect streptavidin-peroxydase staining method was used for immunohistochemical investigation and the following indexes were assessed: proliferating cell nuclear antigen – PCNA, Bcl – 2, Вax, Collagen Type ІV, TGFβ and NF-κβ. Results: Comparative analysis of morphologic investigation has demonstrated that eosinophilic gastritis is characterized by fibrosis and fibroblasts proliferation into basal and superficial parts of mucosa’s lamina propria, multiple hemorrhages, thrombosis and erosions on the background of eosinophilic infiltration. Immunohistochemical indexes of cellular restoration in eosinophilic gastritis are characterized by increased proliferative activity and decreased indexes of proapoptotic and antiapoptotic activity. Prevalence of the reaction with the use of monoclonal antibodies to Collagen Type IV in majority of children with eosinophilic gastritis was characterized by separate fragmented foci in basal membranes of superficial epithelium. Remarkable TGFβ immune coloration was detected in majority of children on the background of fibrosis and eosinophilic infiltration of lamina propria. NF-κβ expression in epitheliocytes’ cytoplasm and nuclei was uneven. Homogenous remarkable coloration was detected in majority of patients with lymphocytic infiltration of mucosa. Conclusions: Eosinophilic gastritis course in children is characterized by remarkable inflammation, decreased regeneration of the mucosa, impairment of cellular restoration which is prognostic index of fibrous remodeling development.

Glycated albumin stimulation of PKC-β activity is linked to increased collagen IV in mesangial cells

1999 ◽  
Vol 276 (5) ◽  
pp. F684-F690 ◽  
Author(s):  
Margo P. Cohen ◽  
Fuad N. Ziyadeh ◽  
Gregory T. Lautenslager ◽  
Jonathan A. Cohen ◽  
Clyde W. Shearman
Keyword(s):  
Collagen Type ◽  
Mesangial Cell ◽  
Mesangial Cells ◽  
Glycated Albumin ◽  
Matrix Proteins ◽  
Collagen Type Iv ◽  
Type Iv ◽  
Pkc Β ◽  
Tgf Β1 ◽  
Stimulation Of

Albumin modified by Amadori-glucose adducts induces coordinate increases in the expression of extracellular matrix proteins, transforming growth factor (TGF)-β1, and the TGF-β type II receptor in glomerular mesangial cells. Because activation of protein kinase C (PKC) accompanies the increased mesangial cell expression of matrix proteins and TGF-β1 induced by high ambient glucose, we postulated that glycated albumin (GA) modulates PKC activity and that PKC participates in mediating the GA-induced stimulation of matrix production. To test this hypothesis, we examined the effects of PKC inhibitors on collagen type IV production by mouse or rat mesangial cells incubated with GA, and the influence of GA on PKC activity in these cells. Increased collagen type IV production evoked by GA in 5.5 and 25 mM glucose in mouse mesangial cells was prevented by both general (GF-109203X) and β-specific (LY-379196) PKC inhibitors. Total PKC activity, measured by phosphorylation of a PKC-specific substrate, increased with time after exposure of rat mesangial cells to GA compared with the nonglycated, glucose-free counterpart. GA caused an increase in PKC-β1 membrane-bound fraction and in total PKC activity in media containing physiological (5.5 mM) glucose concentrations in rat mesangial cells, confirming that the glucose-modified protein, and not a “hyperglycemic” milieu, was responsible. The findings indicate that Amadori-modified albumin stimulates mesangial cell PKC activity, and that activation of the PKC-β isoform is linked to the stimulation of collagen type IV production.

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