The time-dependent expressions of IL-1β, COX-2, MCP-1 mRNA in skin wounds of rabbits

Abstract Background Anterior cruciate ligament transection surgery (ACLT)-induced OA model was often used to investigate the molecular mechanism of knee osteoarthritis (KOA). Researches have shown that vascular endothelial growth factor (VEGF) played an important role in OA. The present study aimed to investigate the pathological changes after ACLT surgery and reveal the expression characteristics of the VEGF-A/VEGFR2 signaling pathway in this model. Methods Moderate KOA model was established by ACLT, and 1, 2, 4, 8, and 12 weeks after surgery, hematoxylin-eosin (HE) and Safranin-O(S-O) staining were used to detect the pathological changes in mouse knee cartilage, and the matrix biomarkers A Disintegrin and Metalloproteinase with Thrombospondin Motifs 5(ADAMTS5), Collagen II (COL-II) were detected using immunohistochemistry (IHC), CD31 was detected by immunofluorescence (IF) to show the vascular invasion in cartilage, and proteins expression of VEGF-A pathway were detected by Western blot (WB). Meanwhile, the inflammatory biomarkers cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in cartilage were detected by WB. Results ACLT surgery can lead to degeneration of cartilage in mice, and the characteristics of the lesion were time-dependent. The ADAMTS5-positive cells increased while COL-II decreased in OA cartilage with time, and new blood vessels labeled by CD31 can be seen from 1 week in OA cartilage, and increased in 8 and 12 weeks. The expression of VEGF-A, VEGFR2, COX-2, and iNOS were higher than control groups, which were basically consistent with the degree of osteoarthritis. Conclusions The degenerative degree of articular cartilage was time-dependent; angiogenesis and inflammation were important pathological changes of cartilage in KOA. The expression of the VEGF-A/VEGFR2 signaling pathway was basically correlated with the degree of KOA.

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Coordinate control of prostaglandin E2 synthesis and uptake by hyperosmolarity in renal medullary interstitial cells

AJP Renal Physiology ◽

10.1152/ajprenal.00426.2004 ◽

2006 ◽

Vol 290 (3) ◽

pp. F641-F649 ◽

Cited By ~ 16

Author(s):

Michael L. Pucci ◽

Shinichi Endo ◽

Teruhisa Nomura ◽

Run Lu ◽

Cho Khine ◽

...

Keyword(s):

Cell Surface ◽

Characteristic Time ◽

Water Deprivation ◽

Interstitial Cells ◽

Time Dependent ◽

Prostaglandin E ◽

Coordinate Control ◽

Time Period ◽

Cox 2 ◽

Net Release

During water deprivation, prostaglandin E2 (PGE2), formed by renal medullary interstitial cells (RMICs), feedback inhibits the actions of antidiuretic hormone. Interstitial PGE2 concentrations represent the net of both PGE2 synthesis by cyclooxygenase (COX) and PGE2 uptake by carriers such as PGT. We used cultured RMICs to examine the effects of hyperosmolarity on both PG synthesis and PG uptake in the same RMIC. RMICs expressed endogenous PGT as assessed by mRNA and immunoblotting. RMICs rapidly took up [3H]PGE2 to a level 5- to 10-fold above background and with a characteristic time-dependent “overshoot.” Inhibitory constants ( Ki) for various PGs and PGT inhibitors were similar between RMICs and the cloned rat PGT. Increasing extracellular hyperosmolarity to the range of 335–485 mosM increased the net release of PGE2 by RMICs, an effect that was concentration dependent, maximal by 24 h, reversible, and associated with increased expression of COX-2. Over the same time period, there was decreased cell-surface activity of PGT due to internalization of the transporter. With continued exposure to hyperosmolarity over 7–10 days, PGE2 release remained elevated, COX-2 returned to baseline, and PGT-mediated uptake became markedly reduced. Our findings suggest that hyperosmolarity induces coordinated changes in COX-2-mediated PGE2 synthesis and PGT-mediated PGE2 uptake in RMICs.

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A role for cyclooxygenase-2 in lipopolysaccharide-induced anorexia in rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00200.2002 ◽

2002 ◽

Vol 283 (4) ◽

pp. R862-R868 ◽

Cited By ~ 59

Author(s):

F. Lugarini ◽

B. J. Hrupka ◽

G. J. Schwartz ◽

C. R. Plata-Salaman ◽

W. Langhans

Keyword(s):

Cerebrospinal Fluid ◽

Cyclooxygenase 2 ◽

Major Metabolite ◽

Time Dependent ◽

Selective Inhibitors ◽

Cox 2 ◽

Cox 1

Because nonselective cycloooxygenase (COX) inhibition attenuated anorexia after lipopolysaccharide (LPS) administration, we tested the ability of resveratrol (2.5, 10, and 40 mg/kg) and NS-398 (2.5, 10, and 40 mg/kg), selective inhibitors of the two COX isoforms COX-1 and -2, respectively, to attenuate LPS (100 μg/kg ip)-induced anorexia. NS-398 (10 and 40 mg/kg) administered with LPS at lights out attenuated LPS-induced anorexia, whereas resveratrol at all doses tested did not. Because prostaglandin (PG) E2 is considered the major metabolite synthesized by COX, we measured plasma and cerebrospinal fluid (CSF) PGE2levels after LPS administration. LPS induced a time-dependent increase of PGE2 in CSF but not in plasma. NS-398 (5, 10, and 40 mg/kg) blocked the LPS-induced increase in CSF PGE2, whereas resveratrol (10 mg/kg) did not. These results support a role of COX-2 in mediating the anorectic response to peripheral LPS and point at PGE2 as a potential neuromodulator involved in this response.

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Urinary tract obstruction induces time‐dependent COX‐2 induction and downregulation of AQP2

The FASEB Journal ◽

10.1096/fasebj.20.5.a1221 ◽

2006 ◽

Vol 20 (5) ◽

Author(s):

Rikke Norregaard ◽

Tina Madsen ◽

Boye L. Jensen ◽

Søren Nielsen ◽

Jørgen Frøkiær

Keyword(s):

Urinary Tract ◽

Urinary Tract Obstruction ◽

Time Dependent ◽

Cox 2

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Kinetic basis for selective inhibition of cyclo-oxygenases

Biochemical Journal ◽

10.1042/bj3390607 ◽

1999 ◽

Vol 339 (3) ◽

pp. 607-614 ◽

Cited By ~ 109

Author(s):

James K. GIERSE ◽

Carol M. KOBOLDT ◽

Mark C. WALKER ◽

Karen SEIBERT ◽

Peter C. ISAKSON

Keyword(s):

Inhibitory Activity ◽

Tight Binding ◽

Selective Inhibition ◽

Time Dependent ◽

Experimental Conditions ◽

Kinetic Behaviour ◽

Competitive Kinetics ◽

Binding Time ◽

Cox 2 ◽

Cox 1

Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit the formation of prostaglandins by cyclo-oxygenases (COX). The discovery of a second COX isoform (COX-2) associated with inflammation led to agents that selectively inhibit COX-2, e.g. celecoxib. We evaluated the kinetics of inhibition of celecoxib and several NSAIDs. Celecoxib displays classic competitive kinetics on COX-1 (Ki = 10-16 μM). An initial competitive interaction with COX-2 can also be discerned with celecoxib (Ki = 11-15 μM), followed by a time-dependent interaction leading to potent inhibition, characterized as inactivation (Kinact = 0.03-0.5 s-1). Half-maximal inhibition (IC50) using end-point assays reflects the competitive component on COX-1 (IC50 = 4-19 μM) and the inactivation component on COX-2 (IC50 = 0.003-0.006 μM). NSAIDs exhibit four distinct modes of COX inhibition based on kinetic behaviour: (1) competitive, e.g. ibuprofen; (2) weak binding, time-dependent, e.g. naproxen, oxicams; (3) tight binding, time-dependent, e.g. indomethacin; (4) covalent, e.g. aspirin. In addition, most NSAIDs display different kinetic behaviour for each isoform. Weakly binding inhibitors show variable behaviour in enzyme assays, with apparent inhibitory activity being markedly influenced by experimental conditions; determination of kinetic constants with this class is unreliable and IC50 values are strongly dependent on assay conditions. Although IC50 determinations are useful for structure/activity analyses, the complex and distinct mechanisms of enzyme inhibition of each COX isoform by the NSAIDs renders comparison of inhibitory activity on COX-1 and COX-2 using IC50 ratios of questionable validity.

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The time-dependent rearrangement of the epithelial basement membrane in human skin wounds —immunohistochemical localization of Collagen IV and VII

International Journal of Legal Medicine ◽

10.1007/bf02340831 ◽

1992 ◽

Vol 105 (2) ◽

pp. 93-97 ◽

Cited By ~ 29

Author(s):

P. Betz ◽

A. Nerlich ◽

J. Wilske ◽

J. Tübel ◽

I. Wiest ◽

...

Keyword(s):

Basement Membrane ◽

Human Skin ◽

Collagen Iv ◽

Immunohistochemical Localization ◽

Time Dependent ◽

Skin Wounds ◽

Epithelial Basement Membrane ◽

Epithelial Basement

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Colon distention induces persistent visceral hypersensitivity by mechanotranscription of pain mediators in colonic smooth muscle cells

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00328.2014 ◽

2015 ◽

Vol 308 (5) ◽

pp. G434-G441 ◽

Cited By ~ 10

Author(s):

You-Min Lin ◽

Yu Fu ◽

Chester C. Wu ◽

Guang-Yin Xu ◽

Li-Yen Huang ◽

...

Keyword(s):

Smooth Muscle ◽

Abdominal Pain ◽

Smooth Muscle Cells ◽

Mechanical Stress ◽

Muscle Cells ◽

Visceral Hypersensitivity ◽

Time Dependent ◽

Rat Colon ◽

Dependent Manner ◽

Cox 2

Abdominal pain and distention are major complaints in irritable bowel syndrome. Abdominal distention is mainly attributed to intraluminal retention of gas or solid contents, which may cause mechanical stress to the gut wall. Visceral hypersensitivity (VHS) may account for abdominal pain. We sought to determine whether tonic colon distention causes persistent VHS and if so whether mechanical stress-induced expression (mechanotranscription) of pain mediators in colonic smooth muscle cells (SMCs) plays a role in VHS. Human colonic SMCs were isolated and stretched in vitro to investigate whether mechanical stress upregulates expression of the pain mediator cyclooxygenase-2 (COX-2). Rat colon was distended with a 5-cm-long balloon, and gene expression of COX-2, visceromotor response (VMR), and sensory neuron excitability were determined. Static stretch of colonic SMCs induced marked expression of COX-2 mRNA and protein in a force- and time-dependent manner. Subnoxious tonic distention of the distal colon at ∼30–40 mmHg for 20 or 40 min induced COX-2 expression and PGE2 production in colonic smooth muscle, but not in the mucosa layer. Lumen distention also increased VMR in a force- and time-dependent manner. The increase of VMR persisted for at least 3 days. Patch-clamp experiments showed that the excitability of colon projecting sensory neurons in the dorsal root ganglia was markedly augmented, 24 h after lumen distention. Administration of COX-2 inhibitor NS-398 partially but significantly attenuated distention-induced VHS. In conclusion, tonic lumen distention upregulates expression of COX-2 in colonic SMC, and COX-2 contributes to persistent VHS.

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Modulation of p21, DAPK1 and COX-2 during the DMBA/TPA-induced mouse skin tumorigenesis and its prevention by phytic acid

Indian Journal of Pharmaceutical and Biological Research ◽

10.30750/ijpbr.2.4.11 ◽

2014 ◽

Vol 2 (04) ◽

pp. 61-67

Author(s):

Chhaya Pandey ◽

Rashmi Arnold ◽

Rahasya Mani Mishra

Keyword(s):

Phytic Acid ◽

Methylation Status ◽

Mouse Skin ◽

Experimental Models ◽

Time Dependent ◽

Dependent Manner ◽

Protective Effects ◽

Skin Tumorigenesis ◽

Naturally Occurring ◽

Cox 2

Chemoprevention by naturally occurring agents is gaining much attention as a newer dimension in the management of cancer. Many naturally occurring agents have shown cancer chemopreventive potential in a variety of bioassay systems and animal models, having relevance to human disease. Phytic acid or Inositol hexaphosphate (IP6), an antioxidant, is a naturally occurring polyphosphorylated carbohydrate that has shown a strong anticancer activity in several experimental models. We assessed the protective effects of Phytic acid against the 7, 12-dimethylbenz [a] anthracene (DMBA)/ 12-O-tetradecanoylphorbol-13- acetate (TPA) induced mouse skin tumorigenesis at 4 and 16 weeks, the time before and after the tumor development. At molecular level we studied expression and promoter CpG methylation status of p21, DAPK1 and COX-2. Our data suggests exposure of DMBA/TPA methylated the promoter region of p21 and DAPK1 genes in time dependent manner that could be the cause of down regulation of their expression with time, which were reversed by administration of phytic acid. But we did not observe methylation in COX-2 whereas upregulation of COX-2 was observed at protein level in mice treated with DMBA followed by TPA in time dependent manner. Administration of phytic acid prevented theses DMBA/TPA induced molecular changes. Study provides a rationale for cancer chemoprevention by natural occurring compounds like Phytic acid.

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Doxycycline Hyclate Modulates Antioxidant Defenses, Matrix Metalloproteinases, and COX-2 Activity Accelerating Skin Wound Healing by Secondary Intention in Rats

Oxidative Medicine and Cellular Longevity ◽

10.1155/2021/4681041 ◽

2021 ◽

Vol 2021 ◽

pp. 1-16

Author(s):

Luciana S. Altoé ◽

Raul S. Alves ◽

Lyvia L. Miranda ◽

Mariáurea M. Sarandy ◽

Daniel S. S. Bastos ◽

...

Keyword(s):

Wound Healing ◽

Wistar Rats ◽

Skin Wound ◽

Antioxidant Potential ◽

Skin Wounds ◽

Doxycycline Hyclate ◽

Skin Wound Healing ◽

Cox 2

The main objective of this study was to investigate the action of doxycycline hyclate (Dx) in the skin wound healing process in Wistar rats. We investigated the effect of Dx on inflammatory cell recruitment and production of inflammatory mediators via in vitro and in vivo analysis. In addition, we analyzed neovascularization, extracellular matrix deposition, and antioxidant potential of Dx on cutaneous repair in Wistar rats. Male animals ( n = 15 ) were divided into three groups with five animals each (protocol: 72/2017), and three skin wounds (12 mm diameter) were created on the back of the animals. The groups were as follows: C, received distilled water (control); Dx1, doxycycline hyclate (10 mg/kg/day); and Dx2, doxycycline hyclate (30 mg/kg/day). The applications were carried out daily for up to 21 days, and tissues from different wounds were removed every 7 days. Our in vitro analysis demonstrated that Dx led to macrophage proliferation and increased N-acetyl-β-D-glucosaminidase (NAG) production, besides decreased cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), and metalloproteinases (MMP), which indicates that macrophage activation and COX-2 inhibition are possibly regulated by independent mechanisms. In vivo, our findings presented increased cellularity, blood vessels, and the number of mast cells. However, downregulation was observed in the COX-2 and PGE2 expression, which was limited to epidermal cells. Our results also showed that the downregulation of this pathway benefits the oxidative balance by reducing protein carbonyls, malondialdehyde, nitric oxide, and hydrogen peroxide (H2O2). In addition, there was an increase in the antioxidant enzymes (catalase and superoxide dismutase) after Dx exposure, which demonstrates its antioxidant potential. Finally, Dx increased the number of types I collagen and elastic fibers and reduced the levels of MMP, thus accelerating the closure of skin wounds. Our findings indicated that both doses of Dx can modulate the skin repair process, but the best effects were observed after exposure to the highest dose.

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