Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 26
Filter
1.
J Plast Reconstr Aesthet Surg ; 84: 368-376, 2023 09.
Article in English | MEDLINE | ID: mdl-37393760

ABSTRACT

AIM: To investigate the impact of ablative fractional carbon dioxide laser (AFCO2L) on patient-reported outcomes measures, subjective scar appearance, dermal architecture, and gene transcription in early burn scars. METHODS: Fifteen adult patients with a burn-related scar were recruited. Inclusion criteria were two non-contiguous scar areas of 1% total body surface area, similar baseline Vancouver scar scale (VSS) score and 3months since the time of injury. All participants acted as their own control. Scars were randomized to treatment or control. Treatment scars received three AFCO2L treatments at 6-week intervals. Outcome measures were recorded at baseline, 3, 6, and 12-months post-treatment. Measures included blinded VSS, Patient Observer Scar Assessment Scale (POSAS), Brisbane Burn Scar Impact Profile (BBSIP), blinded scar photo assessment, histological tissue analysis, and RNA sequencing analysis. RESULTS: No significant difference was found in VSS, scar erythema, or pigmentation. Patient POSAS improved in scar thickness and texture following AFCO2L. All elements of BBSIP improved in control and laser groups. AFCO2L-treated scars were scored better than control scars by blinded raters. RNA sequencing illustrated that AFCO2L induced sustained changes in fibroblast gene expression. CONCLUSIONS: AFCO2L treated scars had significantly altered scar thickness and texture 6 months post-laser and were rated better than controls on blinded photo analysis after 3 treatments. RNASeq results suggest laser treatment alters the transcriptome of treated fibroblasts for at least 3 months after treatment. Expansion of this research to study in more depth fibroblast changes in response to laser, as well as assessing the impact on daily activity and quality of life, will be beneficial.


Subject(s)
Burns , Cicatrix, Hypertrophic , Lasers, Gas , Adult , Humans , Cicatrix/etiology , Cicatrix/surgery , Cicatrix/pathology , Lasers, Gas/therapeutic use , Treatment Outcome , Prospective Studies , Quality of Life , Burns/complications , Carbon Dioxide , Cicatrix, Hypertrophic/pathology
2.
Eplasty ; 23: e6, 2023.
Article in English | MEDLINE | ID: mdl-36817366

ABSTRACT

Background: The authors report the rare, but potentially blinding, complication of bilateral endogenous bacterial endophthalmitis observed in a 35-year-old man during his admission to a regional burns center following a burn injury from an electronic cigarette device. This complication has been reported only twice in burn patients following extensive and life-threatening burn injuries. This patient underwent surgical debridement and split-thickness skin grafting of non-major burns as per standard of practice. In the postoperative period, the patient developed bilateral eye pain, redness, and photophobia, and was subsequently diagnosed with bilateral endogenous bacterial endophthalmitis secondary to a Staphylococcus aureus infection of the burn wound. After ophthalmology input and treatment with systemic and intravitreal antibiotics, he made a full recovery from both his burns and endophthalmitis. Conclusions: This report describes a rare, sight-threatening complication that arose from an infected burn wound in an otherwise healthy patient. It highlights the importance of prompt diagnosis and treatment to preserve vision and the need for burn surgeons to have a high level of awareness of this entity, even in the context of minor burns.

4.
Wound Repair Regen ; 28(6): 710-718, 2020 11.
Article in English | MEDLINE | ID: mdl-32515036

ABSTRACT

Epigenetic regulatory mechanisms are essential for maintaining skin homeostasis and aid in the processes of wound healing. The nucleus co-ordinates gene expression using epigenetic regulatory mechanisms based on distinct chromatin structural states and their remodeling. These include DNA methylation and hydroxymethylation, post-translational histone modifications, ATP-dependent chromatin remodeling and higher-order chromatin structure and 3D genome organization. Epigenetic pathways play a key role in co-ordinating the behavior and activity of the multitude of cell types seen during skin repair, and research is now focusing on how wound healing can be modulated by altering the activity of certain reparative genes. Herein, we aim to highlight recent advances in understanding epigenetic regulatory mechanisms, with particular reference to those involved in keratinocyte and fibroblast biology. We also propose future directions for exploration of epigenetic mechanisms, and their potential clinical applications in acute wound care.


Subject(s)
Chromatin/genetics , Epigenesis, Genetic , Histones/genetics , Keratinocytes/metabolism , Skin/metabolism , Wound Healing/genetics , Animals , Chromatin/metabolism , DNA Methylation , Fibroblasts/metabolism , Fibroblasts/pathology , Histones/metabolism , Humans , Keratinocytes/pathology , Skin/pathology
5.
J Burn Care Res ; 41(4): 878-881, 2020 07 03.
Article in English | MEDLINE | ID: mdl-32141503

ABSTRACT

Hot water immersion (HWI) therapy is an effective and validated treatment for a variety of marine stings. Unsupervised, however, it poses a significant risk of thermal injury. Herein, we describe our experience of iatrogenic thermal injury secondary to marine sting treatment. A 5-year retrospective review of all iatrogenic thermal burns secondary to marine stings referred to the State Adult Burn Service was conducted. Nine patients were identified, all sustaining stings to the feet from estuarine cobblerfish, stonefish, and stingrays. All patients continued unsupervised HWI at home and sustained thermal injury to their feet. The majority were treated conservatively with dressings and elevation. One patient required surgical debridement. While heat application is an effective treatment for marine stings, further patient education is required following discharge from point of care. We recommend that first-aid treatment guidelines be updated to reflect that patients are not recommended to continue scalding water immersion at home. However, if patients wish to continue HWI, water temperature should be checked manually with a thermometer or with a nonstung limb and limited to 30 minutes immersion, with 30-minute skin recovery time between.


Subject(s)
Bites and Stings/therapy , Burns/etiology , Foot Injuries/therapy , Hot Temperature/adverse effects , Immersion/adverse effects , Adult , Animals , Female , First Aid , Fishes , Foot Injuries/etiology , Humans , Iatrogenic Disease , Male , Middle Aged , Retrospective Studies , Young Adult
7.
Adv Wound Care (New Rochelle) ; 3(7): 468-475, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-25032066

ABSTRACT

Significance: Epigenetic regulatory mechanisms are essential for epidermal homeostasis and contribute to the pathogenesis of many skin diseases, including skin cancer and psoriasis. However, while the epigenetic regulation of epidermal homeostasis is now becoming active area of research, the epigenetic mechanisms controlling the wound healing response remain relatively untouched. Recent Advances: Substantial progress achieved within the last two decades in understanding epigenetic mechanisms controlling gene expression allowed defining several levels, including covalent DNA and histone modifications, ATP-dependent and higher-order chromatin chromatin remodeling, as well as noncoding RNA- and microRNA-dependent regulation. Research pertained over the last few years suggests that epigenetic regulatory mechanisms play a pivotal role in the regulation of skin regeneration and control an execution of reparative gene expression programs in both skin epithelium and mesenchyme. Critical Issues: Epigenetic regulators appear to be inherently involved in the processes of skin repair, and are able to dynamically regulate keratinocyte proliferation, differentiation, and migration, together with influencing dermal regeneration and neoangiogenesis. This is achieved through a series of complex regulatory mechanisms that are able to both stimulate and repress gene activation to transiently alter cellular phenotype and behavior, and interact with growth factor activity. Future Directions: Understanding the molecular basis of epigenetic regulation is a priority as it represents potential therapeutic targets for the treatment of both acute and chronic skin conditions. Future research is, therefore, imperative to help distinguish epigenetic modulating drugs that can be used to improve wound healing.

8.
J Invest Dermatol ; 134(3): 827-837, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24126843

ABSTRACT

Bone morphogenetic protein (BMP) signaling plays a key role in the control of skin development and postnatal remodeling by regulating keratinocyte proliferation, differentiation, and apoptosis. To study the role of BMPs in wound-induced epidermal repair, we used transgenic mice overexpressing the BMP downstream component Smad1 under the control of a K14 promoter as an in vivo model, as well as ex vivo and in vitro assays. K14-caSmad1 (transgenic mice overexpressing a constitutively active form of Smad1 under K14 promoter) mice exhibited retarded wound healing associated with significant inhibition of proliferation and increased apoptosis in healing wound epithelium. Furthermore, microarray and quantitative real-time reverse-transcriptase-PCR (qRT-PCR) analyses revealed decreased expression of a number of cytoskeletal/cell motility-associated genes including wound-associated keratins (Krt16, Krt17) and Myosin VA (Myo5a), in the epidermis of K14-caSmad1 mice versus wild-type (WT) controls during wound healing. BMP treatment significantly inhibited keratinocyte migration ex vivo, and primary keratinocytes of K14-caSmad1 mice showed retarded migration compared with WT controls. Finally, small interfering RNA (siRNA)-mediated silencing of BMPR-1B in primary mouse keratinocytes accelerated cell migration and was associated with increased expression of Krt16, Krt17, and Myo5a compared with controls. Thus, this study demonstrates that BMPs inhibit keratinocyte proliferation, cytoskeletal organization, and migration in regenerating skin epithelium during wound healing, and raises a possibility for using BMP antagonists for the management of chronic wounds.


Subject(s)
Apoptosis/physiology , Bone Morphogenetic Proteins/metabolism , Epidermis/physiology , Keratinocytes/physiology , Signal Transduction/physiology , Wound Healing/physiology , Animals , Bone Morphogenetic Protein Receptors, Type I/genetics , Bone Morphogenetic Protein Receptors, Type I/metabolism , Bone Morphogenetic Proteins/genetics , Cell Movement/physiology , Cell Proliferation , Cells, Cultured , Epidermal Cells , Humans , Keratin-14/genetics , Keratinocytes/cytology , Mice , Mice, Inbred Strains , Mice, Transgenic , RNA, Small Interfering/genetics , Smad1 Protein/genetics , Smad1 Protein/metabolism
9.
Crit Care Med ; 40(3): 886-94, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22020240

ABSTRACT

BACKGROUND: One form of sepsis, or endotoxic shock, is a hyperactivated systemic response caused by excessive expression of proinflammatory mediators, which results from Gram-negative bacterial lipopolysaccharide-stimulated Toll-like receptor-4 signaling. This lipopolysaccharide signaling is known to consist of a MyD88-dependent nuclear factor-κB-mediated pathway that results in production of proinflammatory mediators (tumor necrosis factor-α, interleukin-6, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, inducible nitric oxide synthase, cyclooxygenase-2) and a MyD88-independent interferon regulatory factor-mediated pathway that regulates production of Type 1 interferon-inducible proteins (interferon γ-induced protein-10, monocyte chemotactic protein-1). In prior studies, phenylmethimazole markedly decreased virally induced Toll-like receptor-3 expression and signaling and significantly suppressed murine colitis in an experimental model wherein lipopolysaccharide is known to play an important role. OBJECTIVE: In this study, we probed the hypothesis that phenylmethimazole inhibits lipopolysaccharide-mediated Toll-like receptor-4 signaling and is efficacious in attenuating inflammatory changes and improving survival in an in vivo murine model of endotoxic shock. DESIGN: Experimental animal model. SETTING: University laboratory. SUBJECTS: Male C57BL/6J mice weighing 18-22 g. INTERVENTIONS: Phenylmethimazole (1 mg/kg) was administered intraperitoneally to mice before a lethal lipopolysaccharide challenge (25 mg/kg). RAW264.7 mouse macrophage cells were pretreated with phenylmethimazole followed by lipopolysaccharide stimulation. MEASUREMENTS AND MAIN RESULTS: : Macroscopic observations revealed that phenylmethimazole was significantly protective in controlling clinical manifestations of endotoxic shock and death under conditions wherein flunixin of meglumine and prednisolone were marginally effective. A combination of enzyme-linked immunosorbent assay, Northern blot, reverse transcriptase-polymerase chain reaction, immunohistochemistry, and Western blot analyses showed that phenylmethimazole attenuated lipopolysaccharide-induced increases in production of proinflammatory cytokines (tumor necrosis factor-α, interleukin-6, interferon-γ), endothelial cell adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1), inducible nitric oxide synthase and cyclooxygenase-2, interferon regulatory factor-1, interferon-inducible proteins (interferon γ-induced protein-10, monocyte chemotactic protein-1), and signal transducer and activator of transcription-1 phosphorylation in multiple tissues in mice. Consistent with these observations, electrophoretic mobility shift assay demonstrated that phenylmethimazole inhibited in vitro lipopolysaccharide-induced nuclear factor-κB and interferon regulatory factor-1 activation in RAW 264.7 mouse macrophages. CONCLUSIONS: Collectively, these results provide direct evidence that phenylmethimazole diminishes lipopolysaccharide-induced MyD88-dependent as well as MyD88-independent signaling pathways and is protective in an experimental model of endotoxic shock.


Subject(s)
Cytokines/biosynthesis , Cytokines/drug effects , Methimazole/analogs & derivatives , Shock, Septic/immunology , Shock, Septic/prevention & control , Thiones/therapeutic use , Animals , Disease Models, Animal , Inflammation/immunology , Male , Methimazole/therapeutic use , Mice , Mice, Inbred C57BL , Shock, Septic/metabolism
10.
Open Circ Vasc J ; 5: 1-7, 2012.
Article in English | MEDLINE | ID: mdl-25530821

ABSTRACT

OBJECTIVE: Wnt5a is a secreted glycoprotein highly present in atherosclerotic lesions. Uptake of oxidized-low density lipoprotein (ox-LDL) by monocytes/macrophages plays a critical role in atherosclerosis. The objective of this study was to determine if Wnt5a mRNA expression correlates with the severity of atherosclerotic lesions, and if, ox-LDL can induce Wnt5a mRNA in macrophages. METHODS: Wnt5a mRNA in tissue sections from carotid arteries of patients undergoing endarterectomy was quantified via RT-PCR and correlated with plaque severity. Human monocyte-derived macrophages and differentiated THP-1 cells, a human monocytic cell line, were treated with ox-LDL or native-LDL. Subsequently, Wnt5a transcripts were quantified by RT-PCR. RESULTS: Regions of the arteries with more severe plaques had detectable and significant levels of Wnt5a mRNA, while regions of the arteries containing less vulnerable plaques had low or non-detectable Wnt5a. Ox-LDL, but not native-LDL, induced Wnt5a mRNA in both human monocyte-derived macrophages and differentiated THP-1 cells. CONCLUSION: Our results demonstrate that the expression of Wnt5a correlates with the severity of atherosclerotic lesions, and that ox-LDL induces Wnt5a mRNA expression in human macrophages. These findings are consistent with the hypothesis that Wnt5a plays a critical role in atherosclerosis progression and that a source of Wnt5a is ox-LDL stimulated macrophages.

11.
J Cell Sci ; 124(Pt 20): 3399-404, 2011 Oct 15.
Article in English | MEDLINE | ID: mdl-21984808

ABSTRACT

Bone morphogenetic proteins (BMPs) play essential roles in the control of skin development, postnatal tissue remodelling and tumorigenesis. To explore whether some of the effects of BMP signalling are mediated by microRNAs, we performed genome-wide microRNA (miRNA) screening in primary mouse keratinocytes after BMP4 treatment. Microarray analysis revealed substantial BMP4-dependent changes in the expression of distinct miRNAs, including miR-21. Real-time PCR confirmed that BMP4 dramatically inhibits miR-21 expression in the keratinocytes. Consistently, significantly increased levels of miR-21 were observed in transgenic mice overexpressing the BMP antagonist noggin under control of the K14 promoter (K14-noggin). By in situ hybridization, miR-21 expression was observed in the epidermis and hair follicle epithelium in normal mouse skin. In K14-noggin skin, miR-21 was prominently expressed in the epidermis, as well as in the peripheral portion of trichofolliculoma-like hair follicle-derived tumours that contain proliferating and poorly differentiated cells. By transfecting keratinocytes with a miR-21 mimic, we identified the existence of two groups of the BMP target genes, which are differentially regulated by miR-21. These included selected BMP-dependent tumour-suppressor genes (Pten, Pdcd4, Timp3 and Tpm1) negatively regulated by miR-21, as well as miR-21-independent Id1, Id2, Id3 and Msx2 that predominantly mediate the effects of BMPs on cell differentiation. In primary keratinocytes and HaCaT cells, miR-21 prevented the inhibitory effects of BMP4 on cell proliferation and migration. Thus, our study establishes a novel mechanism for the regulation of BMP-induced effects in the skin and suggests miRNAs are important modulators of the effects of growth factor signalling pathways on skin development and tumorigenesis.


Subject(s)
Bone Morphogenetic Protein 4/metabolism , Epidermis , Gene Expression Regulation, Neoplastic , Keratinocytes/metabolism , MicroRNAs/metabolism , Animals , Carrier Proteins/genetics , Carrier Proteins/metabolism , Cell Transformation, Neoplastic/genetics , Cells, Cultured , Epidermis/physiology , Epidermis/physiopathology , Genes, Tumor Suppressor/physiology , Genome-Wide Association Study , Keratin-14/genetics , Keratinocytes/pathology , Mice , Mice, Inbred Strains , Mice, Transgenic , MicroRNAs/genetics , Microarray Analysis , Morphogenesis/genetics , Signal Transduction
12.
Antimicrob Agents Chemother ; 55(12): 5547-52, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21896905

ABSTRACT

Innovative methods of prevention are needed to stop the more than two million new HIV-1 infections annually, particularly in women. Local application of anti-HIV antibodies has been shown to be effective at preventing infection in nonhuman primates; however, the concentrations needed are cost prohibitive. Display of antibodies on a particulate platform will likely prolong effectiveness of these anti-HIV agents and lower the cost of goods. Here, we demonstrate that the bacterium Caulobacter crescentus and its highly expressed surface-layer (S-layer) protein can provide this antibody display platform. Caulobacters displaying protein G, alone or with CD4 codisplay, successfully captured HIV-1-specific antibodies and demonstrated functional neutralization. Compared to soluble antibodies, a neutralizing anti-HIV antibody displayed on Caulobacter was as effective or more effective at neutralizing diverse HIV-1 isolates. Moreover, when an antibody reactive with an epitope induced by CD4 binding (CD4i) was codisplayed with CD4, there was significant enhancement in HIV-1 neutralization. These results suggest that caulobacters displaying anti-HIV antibodies offer a distinct improvement in the use of antibodies as microbicides. Furthermore, these reagents can specifically evaluate anti-HIV antibodies in concert with other HIV-1 blocking agents to assess the most suitable tools for conversion to scFvs, allowing for direct display within the S-layer protein and further reducing cost of goods. In summary, C. crescentus, which can be easily produced and chemically stabilized at low cost, is well suited for engineering as an effective platform, offering an inexpensive way to produce and deliver HIV-1-specific microbicides.


Subject(s)
Anti-HIV Agents/immunology , Caulobacter crescentus/metabolism , HIV Antibodies/immunology , HIV Infections/immunology , HIV-1/immunology , Membrane Glycoproteins/metabolism , CD4 Antigens/genetics , CD4 Antigens/metabolism , Caulobacter crescentus/genetics , Drug Delivery Systems , Female , Genetic Engineering/methods , HIV Antibodies/isolation & purification , HIV Antibodies/metabolism , HIV Infections/drug therapy , HIV Infections/virology , Humans , Membrane Glycoproteins/genetics , Neutralization Tests , Recombinant Proteins/genetics , Recombinant Proteins/metabolism
13.
Ann Biomed Eng ; 39(10): 2627-36, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21796502

ABSTRACT

Pathological inflammation and endothelial dysfunction in atherosclerosis causes endothelial cell detachment from affected vasculature giving rise to circulating endothelial cells (CECs). A blood-based assay that can detect and characterize CECs in atherosclerosis could serve as a valuable diagnostic. Thus, we sought to develop a prototypic assay that detects and characterizes the inflammatory state of endothelial cells present in blood. For this purpose, we spiked resting and inflamed human umbilical vein endothelial cells (HUVEC) into separate samples of whole blood. RNA was harvested and analyzed via quantitative real-time PCR (qPCR) using melanoma cell adhesion molecule (MCAM), as an endothelial marker, and vascular cell adhesion molecule (VCAM-1), which is increased on inflamed endothelium. We found that MCAM mRNA levels correlated with the number of HUVEC spiked into the blood. VCAM-1 mRNA levels were elevated, and correlated with the number of HUVEC, in blood spiked with inflamed HUVEC but not in blood spiked with resting HUVEC. VCAM-1 and MCAM mRNA levels were converted into numerical indices that indicate the inflammatory state of the HUVEC. Combined, the blood spiking studies demonstrate that a VCAM-1/MCAM qPCR assay can successfully detect inflamed endothelial cells in whole blood thus providing proof-of-concept for a diagnostic based on a coupled-phenotypic qPCR assay.


Subject(s)
Human Umbilical Vein Endothelial Cells , Inflammation/blood , Vascular Cell Adhesion Molecule-1/blood , Atherosclerosis/diagnosis , Atherosclerosis/physiopathology , CD146 Antigen/blood , CD146 Antigen/genetics , Cells, Cultured , Endothelium, Vascular/cytology , Endothelium, Vascular/metabolism , Human Umbilical Vein Endothelial Cells/cytology , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Inflammation/metabolism , Real-Time Polymerase Chain Reaction , Vascular Cell Adhesion Molecule-1/genetics
14.
Vet Clin North Am Food Anim Pract ; 27(1): 121-126, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21215896

ABSTRACT

Clostridia cause many different diseases, all characterized by sudden death, most occurring worldwide. Diseases caused by clostridia can be divided into 4 groups: those affecting the alimentary system (the enterotoxemias), those affecting the parenchymatous organs, those causing myonecrosis and toxemia, and those causing neurologic disorders. Their mode of action is to produce one or more potent toxins when multiplying under favorable conditions. Considerable variation exists between different strains of the same organism. Specific trigger factors are required to induce toxin production. Excellent control is obtained by the use of toxoid vaccines. Protection is passed to the lamb via the colostrum.


Subject(s)
Bacterial Toxins/metabolism , Clostridium Infections/veterinary , Sheep Diseases/prevention & control , Vaccination/veterinary , Animals , Animals, Newborn , Bacterial Toxins/analysis , Bacterial Vaccines/administration & dosage , Clostridium/immunology , Clostridium Infections/prevention & control , Colostrum/immunology , Immunization, Passive/veterinary , Sheep
15.
Vet Clin North Am Food Anim Pract ; 27(1): 203-212, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21215904

ABSTRACT

Ectoparasites are a major concern in sheep flocks, wherever sheep are kept. Techniques to control and eradicate lice, ked, or scab have been available since the beginning of the 20th century, but the parasites still exist. Sheep scab (Psoroptes ovis) was eradicated from Australia in the late 1800s, before many of the more effective chemicals were available, and sheep ked is believed to also have been eradicated. Sheep scab has also been eradicated from North America. This article provides an overview of the common ectoparasites of sheep, effective products to control these parasites, and management factors that affect the success of these treatments.


Subject(s)
Ectoparasitic Infestations/veterinary , Sheep Diseases/prevention & control , Animals , Ectoparasitic Infestations/prevention & control , Insecticides/therapeutic use , Lice Infestations/prevention & control , Lice Infestations/veterinary , Mite Infestations/prevention & control , Mite Infestations/veterinary , Scabies/prevention & control , Scabies/veterinary , Sheep , Treatment Outcome
16.
J Endocrinol ; 207(3): 343-53, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20813836

ABSTRACT

Visceral adipocytes and associated macrophages produce and release excessive amounts of biologically active inflammatory cytokines via the portal and systemic vascular system, which induce insulin resistance in insulin target tissues such as fat, liver, and muscle. Free fatty acids (FFAs) absorbed via the portal system or released from adipocytes also induce insulin resistance. In this report, we show that phenylmethimazole (C10) blocks basal IL6 and leptin production as well as basal Socs-3 expression in fully differentiated 3T3L1 cells (3T3L1 adipocytes) without affecting insulin-stimulated AKT signaling. In addition, C10 inhibits palmitate-induced IL6 and iNos up-regulation in both 3T3L1 adipocytes and RAW 264.7 macrophages, LPS-induced NF-κB and IFN-ß activation in 3T3L1 cells, and LPS-induced iNos, Ifn-ß, Il1ß, Cxcl10, and Il6 expression in RAW 264.7 macrophages. C10 also blocks palmitate-induced Socs-3 up-regulation and insulin receptor substrate-1 (IRS-1) serine 307 phosphorylation in 3T3L1 adipocytes. Additionally, we show for the first time that although palmitate increases IRS-1 serine 307 phosphorylation in 3T3L1 adipocytes, AKT serine 473 phosphorylation is enhanced, not reduced, by palmitate. These results suggest that through inhibition of FFA-mediated signaling in adipocytes and associated macrophages, as well as possibly other insulin target cells/tissues (i.e. non-immune cells), C10 might be efficacious to prevent or reverse cytokine-induced insulin resistance seen in obesity-related insulin resistance and type 2 diabetes mellitus.


Subject(s)
Adipocytes/drug effects , Inflammation Mediators/antagonists & inhibitors , Macrophages/drug effects , Methimazole/analogs & derivatives , Palmitates/metabolism , Thiones/pharmacology , 3T3-L1 Cells , Adipocytes/metabolism , Animals , Chemokine CXCL10/antagonists & inhibitors , Insulin/metabolism , Insulin Receptor Substrate Proteins/analysis , Insulin Resistance , Interferon-beta/antagonists & inhibitors , Interleukin-1beta/antagonists & inhibitors , Interleukin-6/antagonists & inhibitors , Leptin/antagonists & inhibitors , Lipopolysaccharides/antagonists & inhibitors , Macrophages/metabolism , Methimazole/pharmacology , Mice , NF-kappa B/antagonists & inhibitors , Nitric Oxide Synthase Type II/antagonists & inhibitors , Palmitates/pharmacology , Phosphorylation/drug effects , Proto-Oncogene Proteins c-akt/analysis , Proto-Oncogene Proteins c-akt/metabolism , Suppressor of Cytokine Signaling 3 Protein , Suppressor of Cytokine Signaling Proteins/antagonists & inhibitors , Up-Regulation/drug effects
17.
Eur J Pharmacol ; 643(1): 129-38, 2010 Sep 15.
Article in English | MEDLINE | ID: mdl-20550948

ABSTRACT

Ulcerative colitis is an autoimmune-inflammatory disease characterized by abnormally increased expression of Toll-like receptor-4 (TLR4) in colonic epithelial cells, increased production of pro-inflammatory cytokines (e.g., TNF-alpha, IL-1beta, IL-6, IL-12), chemokines (e.g., IP-10), and endothelial cell adhesion molecules (e.g., VCAM-1), plus enhanced leukocyte infiltration into colonic interstitium. Previously, we have shown that phenyl methimazole (C10) markedly decreases virally-induced TLR-3 expression and signaling and potently inhibits both TNF-alpha-induced VCAM-1 expression and the resultant leukocyte-endothelial cell adhesion. In this study we probed the hypothesis that C10 is efficacious in a TLR-4- and VCAM-1-associated murine model [the dextran sulfate sodium (DSS) model] of human colitis. C10 was administered intraperitoneally coincident with or after DSS treatment was initiated. Macroscopic colon observations revealed that C10 significantly reversed DSS-induced shortening of the colon (P<0.05) and reduced the presence of blood in the colon. Histological analyses of colonic tissues revealed that C10 distinctly attenuated both DSS-induced edema as well as leukocyte infiltration in the colonic mucosa and resulted in pronounced protection against DSS-induced crypt damage (P<0.001). Northern blot analyses and immunohistochemistry of colonic tissue revealed that C10 markedly diminished DSS-induced expression of pertinent inflammatory mediators: TNF-alpha, IL-1beta, IL-6, IL-12, IP-10, TLR-4 and VCAM-1. Most importantly, C10 significantly improved survival and protected mice against DSS-induced colitic-death: 75% by comparison to 12.5% with identical treatment with DMSO-control (log rank test: P=0.005). These results provide direct evidence that C10 suppresses DSS-induced colitis by inhibiting expression of key inflammatory mediators and leukocyte infiltration, and is a potentially attractive therapeutic for colitis.


Subject(s)
Colitis, Ulcerative/prevention & control , Methimazole/analogs & derivatives , Thiones/therapeutic use , Toll-Like Receptor 4/antagonists & inhibitors , Vascular Cell Adhesion Molecule-1/immunology , Animals , Blotting, Northern , Colitis, Ulcerative/immunology , Colitis, Ulcerative/metabolism , Colitis, Ulcerative/pathology , Cytokines/biosynthesis , Cytokines/immunology , Dextran Sulfate , Disease Models, Animal , Immunohistochemistry , Intestinal Mucosa/drug effects , Intestinal Mucosa/immunology , Intestinal Mucosa/pathology , Male , Methimazole/pharmacology , Methimazole/therapeutic use , Mice , Mice, Inbred C57BL , Thiones/pharmacology , Toll-Like Receptor 4/biosynthesis , Vascular Cell Adhesion Molecule-1/biosynthesis
19.
Am J Physiol Heart Circ Physiol ; 294(6): H2864-70, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18456733

ABSTRACT

Atherosclerosis is an inflammatory disease involving the accumulation of macrophages in the intima. Wnt5a is a noncanonical member of the Wnt family of secreted glycoproteins. Recently, human macrophages have been shown to express Wnt5a upon stimulation with bacterial pathogens in vitro and in granulomatous lesions in the lung of Mycobacterium tuberculosis-infected patients. Wnt5a expression has also been liked to Toll-like receptor-4 (TLR-4), an innate immune receptor implicated in atherosclerosis. These observations, along with the fact that Wnt5a is involved in cell migration and proliferation, led us to postulate that Wnt5a plays a role in atherosclerosis. To investigate this hypothesis, we characterized Wnt5a expression in murine and human atherosclerotic lesions. Tissue sections derived from the aortic sinus to the aortic arch of apolipoprotein E-deficient mice and sections derived from the carotid arteries of patients undergoing endarterectomy were subjected to immunohistochemical analysis. All samples were found to be positive for Wnt5a with predominant staining in the areas of macrophage accumulation within the intima. In parallel, we probed for the presence of TLR-4 and found coincident TLR-4 and Wnt5a expression. For both the Wnt5a and TLR-4 staining, consecutive tissue sections treated with an isotype- and species-matched Ig served as a negative control and exhibited little, if any, reactivity. Quantitative RT-PCR revealed that Wnt5a mRNA expression in RAW264.7 murine macrophages can be induced by stimulation with LPS, a known ligand for TLR-4. Combined, these findings demonstrate for the first time Wnt5a expression in human and murine atherosclerotic lesions and suggest that cross talk between TLR-4 and Wnt5a is operative in atherosclerosis.


Subject(s)
Aortic Diseases/metabolism , Atherosclerosis/metabolism , Carotid Artery Diseases/metabolism , Macrophages/chemistry , Proto-Oncogene Proteins/analysis , Wnt Proteins/analysis , Animals , Aortic Diseases/pathology , Apolipoproteins E/genetics , Apolipoproteins E/metabolism , Atherosclerosis/pathology , Carotid Artery Diseases/pathology , Cell Line , Disease Models, Animal , Female , Humans , Immunohistochemistry , Lipopolysaccharides/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , RNA, Messenger/metabolism , Toll-Like Receptor 4/analysis , Wnt Proteins/genetics , Wnt Proteins/metabolism , Wnt-5a Protein
20.
Endocrinology ; 148(9): 4226-37, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17525119

ABSTRACT

High basal levels of TLR3 and Wnt5a RNA are present in papillary thyroid carcinoma (PTC) cell lines consistent with their overexpression and colocalization in PTC cells in vivo. This is not the case in thyrocytes from normal tissue and in follicular carcinoma (FC) or anaplastic carcinoma (AC) cells or tissues. The basally expressed TLR3 are functional in PTC cells as evidenced by the ability of double-strand RNA (polyinosine-polycytidylic acid) to significantly increase the activity of transfected NF-kappaB and IFN-beta luciferase reporter genes and the levels of two end products of TLR3 signaling, IFN-beta and CXCL10. Phenylmethimazole (C10), a drug that decreases TLR3 expression and signaling in FRTL-5 thyrocytes, decreases TLR3 levels and signaling in PTC cells in a concentration-dependent manner. C10 also decreased Wnt5a RNA levels coordinate with decreases in TLR3. E-cadherin RNA levels, whose suppression may be associated with high Wnt5a, increased with C10 treatment. C10 simultaneously decreased PTC proliferation and cell migration but had no effect on the growth and migration of FC, AC, or FRTL-5 cells. C10 decreases high basal phosphorylation of Tyr705 and Ser727 on Stat3 in PTC cells and inhibits IL-6-induced Stat3 phosphorylation. IL-6-induced Stat3 phosphorylation is important both in up-regulating Wnt5a levels and in cell growth. In sum, high Wnt5a levels in PTC cells may be related to high TLR3 levels and signaling; and the ability of phenylmethimazole (C10) to decrease growth and migration of PTC cells may be related to its suppressive effect on TLR3 and Wnt5a signaling, particularly Stat3 activation.


Subject(s)
Carcinoma, Papillary/genetics , Methimazole/analogs & derivatives , Methimazole/pharmacology , Proto-Oncogene Proteins/physiology , Thyroid Neoplasms/genetics , Toll-Like Receptor 3/physiology , Wnt Proteins/physiology , Carcinoma, Papillary/pathology , Cell Division/drug effects , Cell Line, Tumor , Cell Movement/drug effects , Humans , Proto-Oncogene Proteins/genetics , Thyroid Neoplasms/pathology , Toll-Like Receptor 3/genetics , Wnt Proteins/genetics , Wnt-5a Protein
SELECTION OF CITATIONS
SEARCH DETAIL
...