Cellular and humoral responses to collagen–polyvinylpyrrolidone administered during short and long periods in humans

2003 ◽  
Vol 81 (11) ◽  
pp. 1029-1035 ◽  
Author(s):  
Janette Furuzawa-Carballeda ◽  
Emilio Rojas ◽  
Mahara Valverde ◽  
Irma Castillo ◽  
Lino Diaz de León ◽  
...  
Keyword(s):  
Dna Damage ◽  
Type I Collagen ◽  
Cellular Damage ◽  
In Vivo Studies ◽  
Type I ◽  
Healthy Donors ◽  
Collagen Antibodies ◽  
Humoral Responses

Collagen, particularly type I, and its related derivatives have been extensively employed in many areas of pharmacology. The present study was performed to determine the safety of collagen–polyvinylpyrrolidone (collagen–PVP) by in vitro and in vivo studies. Sera and peripheral blood cells from healthy donors without treatment and patients treated with collagen–PVP were evaluated. We observed that the biodrug does not stimulate lymphoproliferation or DNA damage in vitro, nor does it induce human anti-porcine type I collagen or anti-collagen–PVP antibodies in vivo. Furthermore, no hepatic or renal metabolic dysfunctions were observed when collagen–PVP was administered by intradermal or intramuscular routes in short- or long-term treatments. In conclusion, the present work shows that no cellular damage or immunological adverse effects (cellular and humoral) occurred during collagen–PVP treatment, even after more than 400 weeks of consecutive administrations.Key words: collagen–polyvinylpyrrolidone, DNA damage, collagen antibodies, hypertrophic scar.

scholarly journals The inhibitory effect of plasma fibronectin on collagen-induced platelet aggregation

Blood ◽  
1986 ◽  
Vol 67 (2) ◽  
pp. 450-457 ◽  
Author(s):  
DG Moon ◽  
JE Kaplan ◽  
JE Mazurkewicz
Keyword(s):  
Platelet Aggregation ◽  
Type I Collagen ◽  
Inhibitory Effect ◽  
In Vivo Studies ◽  
In Vivo Model ◽  
Type I ◽  
Plasma Fibronectin ◽  
Antithrombotic Effect

Plasma fibronectin (Fn) has been proposed to have an antithrombotic effect, protecting against platelet and fibrinogen consumption after injury. The current study was designed to determine the effect of plasma fibronectin on collagen-induced platelet aggregation. In vitro aggregometry using an isolated homologous rat system, demonstrated a significant (P less than .05) inhibitory effect of 120 micrograms/mL Fn on platelet aggregation as induced by 60 micrograms/mL fibrillar collagen (type I). The inhibition was evidenced by a threefold increase in lag time and a significant decrease in the rate and extent of aggregation. The hypothesis was also tested using an in vivo model of collagen-induced platelet aggregation. The model used was intravenous injection of 2 mg/kg of homologous type I collagen into anesthetized Sprague-Dawley rats. Injection of collagen preincubated with 4 mg/kg Fn resulted in significantly less thrombocytopenia and fibrinogen consumption as compared with injection of collagen alone. The results of both the in vitro and in vivo studies are consistent with the proposed antithrombotic effect of plasma fibronectin.

scholarly journals The inhibitory effect of plasma fibronectin on collagen-induced platelet aggregation

Blood ◽  
1986 ◽  
Vol 67 (2) ◽  
pp. 450-457 ◽  
Author(s):  
DG Moon ◽  
JE Kaplan ◽  
JE Mazurkewicz
Keyword(s):  
Platelet Aggregation ◽  
Type I Collagen ◽  
Inhibitory Effect ◽  
In Vivo Studies ◽  
In Vivo Model ◽  
Type I ◽  
Plasma Fibronectin ◽  
Antithrombotic Effect

Abstract Plasma fibronectin (Fn) has been proposed to have an antithrombotic effect, protecting against platelet and fibrinogen consumption after injury. The current study was designed to determine the effect of plasma fibronectin on collagen-induced platelet aggregation. In vitro aggregometry using an isolated homologous rat system, demonstrated a significant (P less than .05) inhibitory effect of 120 micrograms/mL Fn on platelet aggregation as induced by 60 micrograms/mL fibrillar collagen (type I). The inhibition was evidenced by a threefold increase in lag time and a significant decrease in the rate and extent of aggregation. The hypothesis was also tested using an in vivo model of collagen-induced platelet aggregation. The model used was intravenous injection of 2 mg/kg of homologous type I collagen into anesthetized Sprague-Dawley rats. Injection of collagen preincubated with 4 mg/kg Fn resulted in significantly less thrombocytopenia and fibrinogen consumption as compared with injection of collagen alone. The results of both the in vitro and in vivo studies are consistent with the proposed antithrombotic effect of plasma fibronectin.

scholarly journals NMDA Receptor-mediated CaMKII/ERK Activation Contributes to Renal Fibrosis

2019 ◽  
Author(s):  
Jingyi Zhou ◽  
Shuaihui Liu ◽  
Luying Guo ◽  
Rending Wang ◽  
Jianghua Chen ◽  
...  
Keyword(s):  
Western Blot ◽  
Renal Fibrosis ◽  
Type I Collagen ◽  
Ischemia Reperfusion ◽  
In Vivo Studies ◽  
Type I ◽  
Erk Activation ◽  
Expression Levels

Abstract Background: Renal fibrosis (RF) results in renal function impairment and eventually kidney failure. We found that N-methyl-D-aspartate receptor (NMDAR) played an important role during RF. However, its mechanism of action is yet to be deciphered. Methods: RF was induced in vivo by unilateral ureteral obstruction (UUO) using 8-week-old C57BL/6 mice. The expression levels of the NMDAR’s functional subunit, NR1, was downregulated using lentiviral vector-mediated shRNA interference. Histological changes were observed using Masson’s trichrome staining. Expression of NR1, fibrotic markers (α-smooth muscle actin (α-SMA), type I collagen (COL1A4), S100A4 and fibronectin), and EMT markers (snail and E-cadherin) were measured using immunohistochemistry and western blot analysis. RF was induced after TGF-β-treatment in HK-2 cells in vitro. NMDAR antagonist MK-801 and Ca2+/calmodulin-dependent protein kinase II (CaMKII) antagonist KN-93 were included in this study for pathway determination. Expression of NR1, total and phosphorylation of CaMKII (p-CaMKII), total and p-ERK were measured using western blot and immunofluorescent assays. Results from in vitro studies were confirmed using in vivo studies for NR1, CaMKII and ERK expression levels. In addition, ischemia-reperfusion injury (IRI) mouse model was used to determine whether oral NMDAR inhibitor dextromethorphan (DXM) could inhibit chronic fibrosis. Results: Increased NR1 expression was observed in both UUO-injured kidneys and TGF-β-treated tubular cells. NR1 knockdown and MK801 administration downregulated CaMKII/ERK activation. In vitro administered CaMKII antagonist KN93 reduced ERK phosphorylation and was not affected by NR1 expression levels. DXM protected IRI-injured kidneys from atrophy and fibrosis. Conclusions: NMDAR participates in renal fibrogenesis by activating the CaMKII/ERK pathway. NMDAR could be a potential therapeutic target for renal fibrosis.

Develoapmet of a Tissue Analog for Cartilage Repair

1991 ◽  
Vol 252 ◽  
Author(s):  
J. M. Pachence ◽  
S. R. Frenkel ◽  
H. Lin
Keyword(s):  
Type I Collagen ◽  
Collagen Matrix ◽  
In Vitro Studies ◽  
In Vivo Studies ◽  
Type I ◽  
Collagen Matrices ◽  
Pore Sizes ◽  
The Matrix

ABSTRACTPurified type I collagen was formed into matrices whose pore sizes were defined on the basis of previous results. The first series of in vitro studies measured the metabolism of chondrocytes grown in matrices with various pore sizes; results revealed that the growth rate was independent of the average matrix pore size, but that ckmdrocyte infiltration throughout the matrix was optimal for pore sizes of 100 to 150 un. In a second series of studies, type I collagen was combined with hyaluranic acid; the HyA/collagen matrices had little effect on chcrdrocyte cell growth versus the collagen matrices. A third set of in vitro studies used collagen matrices incorporating varying cornentrations of insulin-like growth factor. It was found that the IGF-1/collagen matrices can significantly effect the growth and metabolism of the clxrihrocytes. These experiments were vital in establishing the collagen matrix parameters which will be used in subsequent in vivo studies.

scholarly journals Effects of chitosan-collagen dressing on wound healing in vitro and in vivo assays

2021 ◽  
Vol 19 ◽  
pp. 228080002198969
Author(s):  
Min-Xia Zhang ◽  
Wan-Yi Zhao ◽  
Qing-Qing Fang ◽  
Xiao-Feng Wang ◽  
Chun-Ye Chen ◽  
...  
Keyword(s):  
Wound Healing ◽  
Wound Dressing ◽  
Type I Collagen ◽  
Inhibition Zone ◽  
Negative Control ◽  
Type I ◽  
Nih3t3 Cells ◽  
Post Operation

The present study was designed to fabricate a new chitosan-collagen sponge (CCS) for potential wound dressing applications. CCS was fabricated by a 3.0% chitosan mixture with a 1.0% type I collagen (7:3(w/w)) through freeze-drying. Then the dressing was prepared to evaluate its properties through a series of tests. The new-made dressing demonstrated its safety toward NIH3T3 cells. Furthermore, the CCS showed the significant surround inhibition zone than empty controls inoculated by E. coli and S. aureus. Moreover, the moisture rates of CCS were increased more rapidly than the collagen and blank sponge groups. The results revealed that the CCS had the characteristics of nontoxicity, biocompatibility, good antibacterial activity, and water retention. We used a full-thickness excisional wound healing model to evaluate the in vivo efficacy of the new dressing. The results showed remarkable healing at 14th day post-operation compared with injuries treated with collagen only as a negative control in addition to chitosan only. Our results suggest that the chitosan-collagen wound dressing were identified as a new promising candidate for further wound application.

Vitamin K promotes mineralization, osteoblast-to-osteocyte transition, and an anticatabolic phenotype by γ-carboxylation-dependent and -independent mechanisms

2009 ◽  
Vol 297 (6) ◽  
pp. C1358-C1367 ◽  
Author(s):  
Gerald J. Atkins ◽  
Katie J. Welldon ◽  
Asiri R. Wijenayaka ◽  
Lynda F. Bonewald ◽  
David M. Findlay
Keyword(s):  
Bone Formation ◽  
Vitamin K ◽  
Type I Collagen ◽  
Vitamin K2 ◽  
Type I ◽  
Vitamin K1 ◽  
Vitamin K3 ◽  
Positive Effect

The vitamin K family members phylloquinone (vitamin K1) and the menaquinones (vitamin K2) are under study for their roles in bone metabolism and as potential therapeutic agents for skeletal diseases. We have investigated the effects of two naturally occurring homologs, phytonadione (vitamin K1) and menatetrenone (vitamin K2), and those of the synthetic vitamin K, menadione (vitamin K3), on human primary osteoblasts. All homologs promoted in vitro mineralization by these cells. Vitamin K1-induced mineralization was highly sensitive to warfarin, whereas that induced by vitamins K2 and K3 was less sensitive, implying that γ-carboxylation and other mechanisms, possibly genomic actions through activation of the steroid xenobiotic receptor, are involved in the effect. The positive effect on mineralization was associated with decreased matrix synthesis, evidenced by a decrease from control in expression of type I collagen mRNA, implying a maturational effect. Incubation in the presence of vitamin K2 or K3 in a three-dimensional type I collagen gel culture system resulted in increased numbers of cells with elongated cytoplasmic processes resembling osteocytes. This effect was not warfarin sensitive. Addition of calcein to vitamin K-treated cells revealed vitamin K-dependent deposition of mineral associated with cell processes. These effects are consistent with vitamin K promoting the osteoblast-to-osteocyte transition in humans. To test whether vitamin K may also act on mature osteocytes, we tested the effects of vitamin K on MLO-Y4 cells. Vitamin K reduced receptor activator of NF-κB ligand expression relative to osteoprotegerin by MLO-Y4 cells, an effect also seen in human cultures. Together, our findings suggest that vitamin K promotes the osteoblast-to-osteocyte transition, at the same time decreasing the osteoclastogenic potential of these cells. These may be mechanisms by which vitamin K optimizes bone formation and integrity in vivo and may help explain the net positive effect of vitamin K on bone formation.

Cells in regenerating deer antler cartilage provide a microenvironment that supports osteoclast differentiation

2001 ◽  
Vol 204 (3) ◽  
pp. 443-455
Author(s):  
C. Faucheux ◽  
S. Nesbitt ◽  
M. Horton ◽  
J. Price
Keyword(s):  
Type I Collagen ◽  
Mononuclear Cells ◽  
Osteoclast Differentiation ◽  
Cathepsin K ◽  
Collagen Matrix ◽  
Tartrate Resistant Acid Phosphatase ◽  
Type I ◽  
Deer Antler

Deer antlers are a rare example of mammalian epimorphic regeneration. Each year, the antlers re-grow by a modified endochondral ossification process that involves extensive remodelling of cartilage by osteoclasts. This study identified regenerating antler cartilage as a site of osteoclastogenesis in vivo. An in vitro model was then developed to study antler osteoclast differentiation. Cultured as a high-density micromass, cells from non-mineralised cartilage supported the differentiation of large numbers of osteoclast-like multinucleated cells (MNCs) in the absence of factors normally required for osteoclastogenesis. After 48 h of culture, tartrate-resistant acid phosphatase (TRAP)-positive mononuclear cells (osteoclast precursors) were visible, and by day 14 a large number of TRAP-positive MNCs had formed (783+/−200 per well, mean +/− s.e.m., N=4). Reverse transcriptase/polymerase chain reaction (RT-PCR) showed that receptor activator of NF κ B ligand (RANKL) and macrophage colony stimulating factor (M-CSF) mRNAs were expressed in micromass cultures. Antler MNCs have the phenotype of osteoclasts from mammalian bone; they expressed TRAP, vitronectin and calcitonin receptors and, when cultured on dentine, formed F-actin rings and large resorption pits. When cultured on glass, antler MNCs appeared to digest the matrix of the micromass and endocytose type I collagen. Matrix metalloproteinase-9 (MMP-9) may play a role in the resorption of this non-mineralised matrix since it is highly expressed in 100 % of MNCs. In contrast, cathepsin K, another enzyme expressed in osteoclasts from bone, is only highly expressed in resorbing MNCs cultured on dentine. This study identifies the deer antler as a valuable model that can be used to study the differentiation and function of osteoclasts in adult regenerating mineralised tissues.

Tissue specificity of type I collagen gene expression is determined at both transcriptional and post-transcriptional levels

1984 ◽  
Vol 4 (9) ◽  
pp. 1843-1852
Author(s):  
R J Focht ◽  
S L Adams
Keyword(s):  
Gene Expression ◽  
Rna Structure ◽  
Type I Collagen ◽  
Translational Efficiency ◽  
Type I ◽  
Collagen Gene ◽  
Differentiated Cells ◽  
Collagen Gene Expression

We analyzed the control of type I collagen synthesis in four kinds of differentiated cells from chicken embryos which synthesize very different amounts of the protein. Tendon, skin, and smooth muscle cells were found to have identical amounts of type I collagen RNAs; however, the RNAs had inherently different translatabilities, which were observed both in vivo and in vitro. Chondrocytes also had substantial amounts of type I collagen RNAs, even though they directed no detectable synthesis of the protein either in vivo or in vitro. Type I collagen RNAs in chondrocytes display altered electrophoretic mobilities, suggesting that in these cells the reduction in translational efficiency may be mediated in part by changes in the RNA structure. These data indicate that control of type I collagen gene expression is a complex process which is exerted at both transcriptional and post-transcriptional levels.

The influence of the haematocrit on primary haemostasis in vitro

2005 ◽  
Vol 94 (12) ◽  
pp. 1213-1218 ◽  
Author(s):  
Marco Eugster ◽  
Walter H. Reinhart
Keyword(s):  
Platelet Function ◽  
Type I Collagen ◽  
Inverse Correlation ◽  
Type I ◽  
Membrane Pore ◽  
Closure Time ◽  
Function Analyzer ◽  
Platelet Function Analyzer

SummaryPrimary haemostasis consists of platelet adhesion to subendothelial collagen, their activation and aggregation and finally the formation of a platelet plug. Erythrocytes are involved in this process because they flow in the center of the vessel and push platelets towards the site of action on the vessel wall and enhance shear forces, which activate platelets. In the platelet function analyzer PFA-100® (Dade Behring, Düdingen, Switzerland), the in vivo situation is simulated in vitro with blood being aspirated at high shear rates (5000s-1) through a capillary into a membrane pore with a diameter of 150 μm coated with type I collagen and either epinephrine or adenosine diphosphate. Aggregating platelets plug the pore and stop the flow, which is measured as the closure time. We analysed the influence of erythrocytes on platelet function analyzer measurements by systematic variation of the haematocrit (20,30,40,and 50%) at constant platelet counts of 289±61 ×103/μl plasma, or 152±30 ×103/μl blood, 96±9 ×103/μl blood and 54±5 ×103/μl blood, respectively. An inverse correlation was found between haematocrit and closure time under all circumstances. A decrease of the platelet count by 50 ×103 /μl could be compensated for by a 10% increase in haematocrit. The haematocrit must, therefore, be taken into consideration for the correct interpretation of PFA-100® measurements. Our data also provide a pathophysiological rationale to reduce the risk of bleeding in patients with thrombocytopenia and anaemia by normalizing the haematocrit with erythrocyte transfusions.

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