scholarly journals Induction of albumin gene transcription in hepatocytes by extracellular matrix proteins.

1990 ◽  
Vol 10 (3) ◽  
pp. 1239-1243 ◽  
Author(s):  
J M Caron
Keyword(s):  
Type Iv Collagen ◽  
Type I Collagen ◽  
Primary Cultures ◽  
Matrix Proteins ◽  
Type I ◽  
Mrna Levels ◽  
Albumin Secretion ◽  
Type Iv ◽  
Albumin Gene ◽  
Albumin Mrna

Transcriptional activity of the albumin gene was induced in primary cultures of hepatocytes by adding dilute concentrations of basement membrane-like proteins derived from the EHS mouse sarcoma tumor to established type I collagen cultures. By immunofluorescence microscopy with antialbumin antibody, the population of cells responded uniformly to dilute EHS. Of the three major components of EHS, purified laminin was as effective as unfractionated EHS at inducing an increase in albumin mRNA levels and albumin secretion; type IV collagen and heparan sulfate proteoglycan were ineffective.

Induction of albumin gene transcription in hepatocytes by extracellular matrix proteins

1990 ◽  
Vol 10 (3) ◽  
pp. 1239-1243
Author(s):  
J M Caron
Keyword(s):  
Type Iv Collagen ◽  
Type I Collagen ◽  
Primary Cultures ◽  
Matrix Proteins ◽  
Type I ◽  
Mrna Levels ◽  
Albumin Secretion ◽  
Type Iv ◽  
Albumin Gene ◽  
Albumin Mrna

Transcriptional activity of the albumin gene was induced in primary cultures of hepatocytes by adding dilute concentrations of basement membrane-like proteins derived from the EHS mouse sarcoma tumor to established type I collagen cultures. By immunofluorescence microscopy with antialbumin antibody, the population of cells responded uniformly to dilute EHS. Of the three major components of EHS, purified laminin was as effective as unfractionated EHS at inducing an increase in albumin mRNA levels and albumin secretion; type IV collagen and heparan sulfate proteoglycan were ineffective.

Stimulation of albumin gene transcription by insulin in primary cultures of rat hepatocytes

1987 ◽  
Vol 252 (2) ◽  
pp. C205-C214 ◽  
Author(s):  
C. E. Lloyd ◽  
J. E. Kalinyak ◽  
S. M. Hutson ◽  
L. S. Jefferson
Keyword(s):  
Gene Transcription ◽  
Relative Abundance ◽  
Primary Cultures ◽  
Rat Hepatocytes ◽  
Complementary Strand ◽  
Albumin Secretion ◽  
Single Stranded Dna ◽  
Albumin Gene ◽  
Albumin Mrna ◽  
Stimulation Of

The first goal of the work reported here was to prepare single-stranded DNA sequences for use in studies on the regulation of albumin gene expression. A double-stranded rat albumin cDNA clone was subcloned into the bacteriophage vector M13mp7. Single-stranded recombinant clones were screened for albumin sequences containing either the mRNA strand or the complementary strand. Two clones were selected that contained the 1,200 nucleotide long 3' end of the albumin sequence. DNA from the clone containing the mRNA strand was used as a template for DNA polymerase I to prepare a radiolabeled, single-stranded cDNA to albumin mRNA. This radiolabeled cDNA probe was used to quantitate the relative abundance of albumin mRNA in samples of total cellular RNA. DNA from the clone containing the complementary strand was used to measure relative rates of albumin gene transcription in isolated nuclei. The second goal was to use the single-stranded DNA probes to investigate the mechanism of the insulin-mediated stimulation of albumin synthesis in primary cultures of rat hepatocytes. Addition of insulin to hepatocytes maintained in hepatocytes. Addition of insulin to hepatocytes maintained in a chemically defined, serum-free medium for 40 h in the absence of any hormones resulted in a specific 1.5- to 2.5-fold stimulation of albumin gene transcription that was maximal at 3 h and was maintained above control values for at least 24 h. The relative abundance of albumin mRNA and albumin secretion increased correspondingly within 24 to 30 h. These parameters remained above control levels for at least 60 h after addition of insulin. Maximal responses were attained at an insulin concentration of 100 nM and there was a close correspondence between albumin gene transcription and albumin secretion at each concentration tested. The rate of albumin gene transcription in nuclei isolated from livers of diabetic rats was reduced to 50% of the value recorded in control nuclei. Taken together, these findings demonstrate that insulin regulates synthesis of albumin at the level of gene transcription.

scholarly journals Effects of ECM Proteins and Cationic Polymers on the Adhesion and Proliferation of Rat Islet Cells

2008 ◽  
Vol 2 (1) ◽  
pp. 133-137 ◽  
Author(s):  
Guoping Chen ◽  
Naoki Kawazoe ◽  
Tetsuya Tateishi
Keyword(s):  
Cell Culture ◽  
Type Iv Collagen ◽  
Type I Collagen ◽  
Islet Cells ◽  
Type Ii Collagen ◽  
Type I ◽  
Cationic Polymers ◽  
Type Iv ◽  
Ecm Proteins ◽  
Cationic Polyelectrolytes

The effects of extracellular matrix (ECM) proteins and cationic polymers on the adhesion and proliferation of rat islet cells, RIN-5F cells, were investigated. ECM proteins of laminin, fibronectin, vitronectin, type I collagen, type II collagen, and type IV collagen, and cationic polyelectrolytes of poly(L-lysine) and poly(allylamine) were coated on the wells of polystyrene cell culture plates. Their effects on the adhesion and proliferation of RIN-5F in serum-free and serum mediums were compared. The cell number on the laminin-coated surface was the highest among the coated surfaces. Laminin promoted cell adhesion more strongly than did the other ECM proteins and cationic polyelectrolytes. Vitronectin, type IV collagen, and poly(L-lysine) showed moderate effects, but type I collagen and type II collagen did not have any effects on adhesion and proliferation compared with the uncoated polystyrene cell culture plate. Fibronectin promoted cell adhesion but not cell proliferation. Cationic poly(allylamine) had an inhibitory effect in serum-free medium and for longterm culture in serum medium. The ECM proteins of laminin, vitronectin, and type IV collagen, and cationic poly(Llysine) will be useful for the surface modification and construction of biomaterials and scaffolds for islet cell culture and tissue engineering.

scholarly journals Modulation of extracellular matrix biosynthesis by bovine retinal pericytes in vitro: effects of the substratum and cell density

1990 ◽  
Vol 96 (1) ◽  
pp. 159-169
Author(s):  
A.E. Canfield ◽  
T.D. Allen ◽  
M.E. Grant ◽  
S.L. Schor ◽  
A.M. Schor
Keyword(s):  
Extracellular Matrix ◽  
Type Iv Collagen ◽  
Type I Collagen ◽  
Single Cells ◽  
Collagen Gel ◽  
Type Iii Collagen ◽  
Type I ◽  
Experimental Conditions ◽  
Type Iv ◽  
Retinal Pericytes

Bovine retinal pericytes plated on a two-dimensional substratum display a characteristic stellate morphology. In post-confluent cultures these cells aggregate spontaneously to form multicellular nodules. The same cells plated within a three-dimensional collagen matrix display an elongated sprouting morphology. Sprouting pericytes may be embedded within a gel either as individual cells or as multicellular aggregates. We have compared the nature of the matrix proteins synthesised by pericytes displaying these different phenotypes. Stellate pericytes cultured on plastic dishes synthesised predominantly type I collagen, some type III collagen and only traces of type IV collagen. The same collagen types were secreted when nodules had formed in postconfluent cultures on plastic, and by sprouting cells plated as single cells within the collagen gel. By contrast, sprouting pericytes plated as aggregates within the collagen gel secreted increased levels of type IV collagen and reduced amounts of type I collagen. Fibronectin was synthesized by pericytes under all experimental conditions examined; thrombospondin was produced in relatively large amounts by cells grown on plastic dishes, whereas only trace amounts could be detected in the medium when the cells were cultured within a collagen gel matrix. Transmission electron microscopy revealed that pericyte aggregates within a collagen gel contained cells in close apposition surrounded by a dense extracellular matrix. In contrast, cells in the centre of a nodule on plastic appeared to be separated from each other by loose extracellular material. These results suggest that the morphological and biosynthetic phenotypes of retinal pericytes are modulated by cell-matrix and/or cell-cell interactions.

Distribution of laminin and collagens during avian neural crest development

Development ◽  
1987 ◽  
Vol 101 (3) ◽  
pp. 461-478 ◽  
Author(s):  
J.L. Duband ◽  
J.P. Thiery
Keyword(s):  
Cell Migration ◽  
Neural Crest ◽  
Type Iv Collagen ◽  
Type I Collagen ◽  
Neural Crest Cell ◽  
Type Iii Collagen ◽  
Type I ◽  
Type Iii ◽  
Type Iv ◽  
Crest Cell

The distribution of type I, III and IV collagens and laminin during neural crest development was studied by immunofluorescence labelling of early avian embryos. These components, except type III collagen, were present prior to both cephalic and trunk neural crest appearance. Type I collagen was widely distributed throughout the embryo in the basement membranes of epithelia as well as in the extracellular spaces associated with mesenchymes. Type IV collagen and laminin shared a common distribution primarily in the basal surfaces of epithelia and in close association with developing nerves and muscle. In striking contrast with the other collagens and laminin, type III collagen appeared secondarily during embryogenesis in a restricted pattern in connective tissues. The distribution and fate of laminin and type I and IV collagens could be correlated spatially and temporally with morphogenetic events during neural crest development. Type IV collagen and lamin disappeared from the basal surface of the neural tube at sites where neural crest cells were emerging. During the course of neural crest cell migration, type I collagen was particularly abundant along migratory pathways whereas type IV collagen and laminin were distributed in the basal surfaces of the epithelia lining these pathways but were rarely seen in large amounts among neural crest cells. In contrast, termination of neural crest cell migration and aggregation into ganglia were correlated in many cases with the loss of type I collagen and with the appearance of type IV collagen and laminin among the neural crest population. Type III collagen was not observed associated with neural crest cells during their development. These observations suggest that laminin and both type I and IV collagens may be involved with different functional specificities during neural crest ontogeny. (i) Type I collagen associated with fibronectins is a major component of the extracellular spaces of the young embryo. Together with other components, it may contribute to the three-dimensional organization and functions of the matrix during neural crest cell migration. (ii) Type III collagen is apparently not required for tissue remodelling and cell migration during early embryogenesis. (iii) Type IV collagen and laminin are important components of the basal surface of epithelia and their distribution is consistent with tissue remodelling that occurs during neural crest cell emigration and aggregation into ganglia.

Difference in interaction of fibronectin with type I collagen and type IV collagen

1997 ◽  
Vol 1339 (1) ◽  
pp. 53-61 ◽  
Author(s):  
Mitsuo Shimizu ◽  
Kazunobu Minakuchi ◽  
Mina Moon ◽  
Junichi Koga
Keyword(s):  
Type Iv Collagen ◽  
Type I Collagen ◽  
Type I ◽  
Type Iv

Structural Differences between Type I and Type IV Collagen in Biological Tissues Studied in vivo by Attenuated Total Reflection/Fourier Transform Infrared Spectroscopy

1992 ◽  
Vol 46 (4) ◽  
pp. 626-630 ◽  
Author(s):  
Yukihiro Ozaki ◽  
Aritake Mizuno ◽  
Fumiko Kaneuchi
Keyword(s):  
Fourier Transform ◽  
Type Iv Collagen ◽  
Type I Collagen ◽  
Fourier Transform Infrared ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Random Coil ◽  
Type I ◽  
Type Iv ◽  
Helix Formation

Attenuated total reflection/Fourier transform infrared (ATR/FT-IR) spectra have been obtained in a nondestructive manner for the anterior surface, interior part, and posterior surface of the sclera, for the epithelium, Bowman's membrane, stroma, and endothelium of the cornea, and for the inner section of the Achilles' tendon of a rabbit. The corresponding spectra have been remeasured for the rabbit anterior and posterior lens capsule for purposes of comparison. The spectra of the three parts of the sclera and of the Bowman's membrane and stroma of the cornea are very close to the spectrum of purified type I collagen, confirming that their major components are type I collagen. The spectrum of the tendon is also very similar to that of purified type I collagen, but it contains a small contribution from hyaluronic acid in the 1100-1000 cm−1 region. The amide I bands of the type I collagen-containing tissues are sharp and symmetrical, and their frequencies (1642 cm−1) are almost identical to that (1640 cm−1) of polyglycine II, which takes a 3, helix formation, indicating that the secondary structure of type I collagen in the tissues examined is for practical purposes a slightly modified 31 helix. A comparison of the spectra of the type I collagen-containing tissues and those of the type IV collagen-containing tissues reveals that there are two major differences between them; one is the spectral features in the 1100-1000 cm1 region, where C-O stretching modes of polysaccharide are observed, and the other is the shape and frequency of the amide I band. Besides the peak at 1637 cm−1, the amide I bands of the type IV collagen-containing tissues have shoulders near 1650 and 1655 cm−1. This observation indicates that type IV collagen in the tissues examined assumes primarily a slightly modified 31 helix formation, but the percentages of α-helix and random coil structures are not negligible.

miR-378 reduces mesangial hypertrophy and kidney tubular fibrosis via MAPK signalling

2017 ◽  
Vol 131 (5) ◽  
pp. 411-423 ◽  
Author(s):  
Bo Wang ◽  
Kevin Yao ◽  
Andrea F. Wise ◽  
Ricky Lau ◽  
Hsin-Hui Shen ◽  
...  
Keyword(s):  
Type Iv Collagen ◽  
Type I Collagen ◽  
Transforming Growth Factor ◽  
Mesangial Cell ◽  
Quantitative Polymerase Chain Reaction ◽  
Locked Nucleic Acid ◽  
Type I ◽  
Protective Function ◽  
Type Iv ◽  
Tgf Β1

The regulatory role of a novel miRNA, miR-378, was determined in the development of fibrosis through repression of the MAPK1 pathway, miR-378 and fibrotic gene expression was examined in streptozotocin (STZ)-induced diabetic mice at 18 weeks or in unilateral ureteral obstruction (UUO) mice at 7 days. miR-378 transfection of proximal tubular epithelial cells, NRK52E and mesangial cells was assessed with/without endogenous miR-378 knockdown using the locked nucleic acid (LNA) inhibitor. NRK52E cells were co-transfected with the mothers against decapentaplegic homolog 3 (SMAD3) CAGA reporter and miR-378 in the presence of transforming growth factor-β (TGF-β1) was assessed. Quantitative polymerase chain reaction (qPCR) showed a significant reduction in miR-378 (P<0.05) corresponding with up-regulated type I collagen, type IV collagen and α-smooth muscle actin (SMA) in kidneys of STZ or UUO mice, compared with controls. TGF-β1 significantly increased mRNA expression of type I collagen (P<0.05), type IV collagen (P<0.05) and α-SMA (P<0.05) in NRK52E cells, which was significantly reduced (P<0.05) following miR-378 transfection and reversed following addition of the LNA inhibitor of endogenous miR-378. Overexpression of miR-378 inhibited mesangial cell expansion and proliferation in response to TGF-β1, with LNA–miR-378 transfection reversing this protective effect, associated with cell morphological alterations. The protective function of MAPK1 on miR-378 was shown in kidney cells treated with the MAPK1 inhibitor, selumetinib, which inhibited mesangial cell hypertrophy in response to TGF-β1. Taken together, these results suggest that miR-378 acts via regulation of the MAPK1 pathway. These studies demonstrate the protective function of MAPK1, regulated by miR-378, in the induction of kidney cell fibrosis and mesangial hypertrophy.

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