RESUMO
Several studies have documented the interaction between the immune and endocrine systems as an effective defense strategy against tuberculosis, involving the production of several molecules and immunological processes. In this study, we determined the effect of cortisol and dehydroepiandrosterone (DHEA) on the production of antimicrobial peptides such as cathelicidin and human ß-defensin (HBD) -2, and HBD-3 and their effect on intracellular growth of Mycobacterium tuberculosis (Mtb) in lung epithelial cells and macrophages. Our results showed that DHEA promotes the production of these antimicrobial peptides in infected cells, correlating with the decrease of Mtb bacilli loads. These results suggest the use of exogenous DHEA as an adjuvant for tuberculosis therapy.
Assuntos
Peptídeos Catiônicos Antimicrobianos/biossíntese , Desidroepiandrosterona/farmacologia , Hidrocortisona/farmacologia , Mycobacterium tuberculosis , beta-Defensinas/biossíntese , Células A549 , Células Epiteliais/microbiologia , Humanos , Macrófagos/microbiologia , Células THP-1 , CatelicidinasRESUMO
Bacterial resistance against conventional antibiotics is increasing. This introduces challenges, for example, in the treatment of infected surgical wounds. Host defence peptides (HDP), which are endogenous peptide antibiotics, show broad-spectrum antimicrobial effectiveness. They protect the organism against pathological microorganisms. Synthetic HDP might supplement or even become alternatives to conventional antibiotics. Knowledge of their quantities under physiological and pathophysiological conditions is therefore required. The influence of gender on HDP expression is unknown. This study evaluates whether gender influences HDP expression in infected or healthy epithelium. Expression levels of HDP human beta-defensin (hBD)-1, -2 and -3 and psoriasin (S100A7) were analysed, by using real-time polymerase chain reaction, in samples of epithelium from infected surgical wounds (n = 20) and healthy epithelium (n = 14) from the neck in a basic medical research study (analytic observational design). The results demonstrated a significantly elevated expression of hBD-2, hBD-3 and psoriasin (P = 0.001 each) in infected epithelium compared with healthy epithelium. No difference in HDP expression levels was evident between samples from female and male patients, either within infected samples or within healthy epithelium samples. Thus, gender does not affect the cutaneous expression of the investigated HDP. This is fundamental knowledge for the study and potential use of HDP derivates as alternative antibiotic substances.
Assuntos
Infecções Bacterianas/metabolismo , Epitélio/metabolismo , Proteína A7 Ligante de Cálcio S100/biossíntese , beta-Defensinas/biossíntese , Adolescente , Adulto , Idoso , Infecções Bacterianas/genética , Pesquisa Biomédica , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Proteína A7 Ligante de Cálcio S100/genética , Fatores Sexuais , Adulto Jovem , beta-Defensinas/genéticaRESUMO
In chronic nonhealing wounds, the healing process is disrupted and wounds are often infected with bacteria. About 85% of lower extremity amputations in diabetes are attributed to deep infection of foot ulcers. Therefore, infection control is critical for wound care. In this study, we analyzed lipid composition of Chamaecyparis obtusa extract, and we describe the wound-healing properties of its combination of 10 major lipid components. A 10-lipid mixture up-regulated HBD-3 and LL-37 through the olfactory receptor 2AT4 and induced phosphorylation of extracellular signal-regulated kinases and p38 mitogen-activated protein kinases in primary human keratinocytes. In addition, the 10-lipid mixture had direct bactericidal effects against Staphylococcus aureus and Streptococcus pyogenes and protected against staphylococcal α-toxin-induced keratinocyte cell death. In an animal model, the 10-lipid mixture accelerated skin wound healing and was also effective in healing wounds superinfected with S. aureus. We suggest that the 10-lipid mixture, because of its wound-healing and antimicrobial properties, can be beneficial for wound treatment.
Assuntos
Chamaecyparis , Lipídeos/farmacologia , Extratos Vegetais/farmacologia , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Peptídeos Catiônicos Antimicrobianos/biossíntese , Chamaecyparis/química , Feminino , Humanos , Mediadores da Inflamação/fisiologia , Queratinócitos/efeitos dos fármacos , Camundongos , Camundongos Pelados , beta-Defensinas/biossíntese , CatelicidinasRESUMO
INTRODUCTION: Bacterial resistance against antibiotics has become an increasing challenge in the treatment of cutaneous infections. Consequences can be severe, especially in infected wounds following previous local radiotherapy. Certain endogenous peptide antibiotics, the host defence peptides (HDPs), exhibit broad-spectrum antimicrobial activity and promote wound healing. Their use as supplements to conventional antibiotics is a current topic of discussion; however, knowledge of their quantities in healthy and compromised tissue is a prerequisite for such discussion. To date, no data concerning HDP quantities in irradiated skin are available. METHODS: Expression profiles of the genes encoding HDPs, namely human beta-defensin-1 (DEFB1, hBD-1), beta-defensin-2 (DEFB4A, hBD-2), beta-defensin-3 (DEFB103, hBD-3) and S100A7, were assessed in samples of non-irradiated and irradiated neck. RESULTS: A reduction in the expression of all of the examined genes was observed in irradiated skin when compared with non-irradiated skin (statistically significant in the case of S100A7, P = 0.013). Immunohistochemistry revealed differences in HDP distribution with respect to the epithelial layers. CONCLUSION: The study demonstrates a significant reduction in HDP gene expression in neck skin as a result of radiotherapy. These findings might represent a starting point for novel treatments of cutaneous infections in irradiated patients, such as topical supplementation of synthetic HDP.
Assuntos
Neoplasias Bucais/radioterapia , Proteínas S100/biossíntese , Pele/metabolismo , beta-Defensinas/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Radioterapia/efeitos adversos , Proteína A7 Ligante de Cálcio S100 , Proteínas S100/genética , beta-Defensinas/genéticaRESUMO
ß-Defensins are members of the antimicrobial peptide superfamily that are produced in various species from different kingdoms, including plants. Plant defensins exhibit primarily antifungal activities, unlike those from animals that exhibit a broad-spectrum antimicrobial action. Recently, immunomodulatory roles of mammal ß-defensins have been observed to regulate inflammation and activate the immune system. Similar roles for plant ß-defensins remain unknown. In addition, the regulation of the immune system by mammalian ß-defensins has been studied in humans and mice models, particularly in immune cells, but few studies have investigated these peptides in epithelial cells, which are in intimate contact with pathogens. The aim of this work was to evaluate the effect of the chemically synthesized ß-defensin γ-thionin from Capsicum chinense on the innate immune response of bovine mammary epithelial cells (bMECs) infected with Staphylococcus aureus, the primary pathogen responsible for bovine mastitis, which is capable of living within bMECs. Our results indicate that γ-thionin at 0.1 µg/ml was able to reduce the internalization of S. aureus into bMECs (â¼50%), and it also modulates the innate immune response of these cells by inducing the mRNA expression (â¼5-fold) and membrane abundance (â¼3-fold) of Toll-like receptor 2 (TLR2), as well as by inducing genes coding for the pro-inflammatory cytokines TNF-α and IL-1ß (â¼14 and 8-fold, respectively) before and after the bacterial infection. γ-Thionin also induces the expression of the mRNA of anti-inflammatory cytokine IL-10 (â¼12-fold). Interestingly, the reduction in bacterial internalization coincides with the production of other antimicrobial products by bMECs, such as NO before infection, and the secretion into the medium of the endogenous antimicrobial peptide DEFB1 after infection. The results from this work support the potential use of ß-defensins from plants as immunomodulators of the mammalian innate immune response.
Assuntos
Capsicum/química , Células Epiteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Tioninas/farmacologia , Sequência de Aminoácidos , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Feminino , Regulação da Expressão Gênica/imunologia , Imunidade Inata , Fatores Imunológicos/isolamento & purificação , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/imunologia , Glândulas Mamárias Animais/microbiologia , Extratos Vegetais/química , Cultura Primária de Células , RNA Mensageiro/genética , RNA Mensageiro/imunologia , Transdução de Sinais , Staphylococcus aureus/fisiologia , Tioninas/isolamento & purificação , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , beta-Defensinas/biossíntese , beta-Defensinas/imunologia , beta-Defensinas/metabolismoRESUMO
Paeoniflorin (PF) is one of the principal components of peony, a plant widely used in traditional Chinese medicine for its anti-inflammatory and immunomodulatory effects. Human ß-defensin-2 (hBD-2) is an antimicrobial peptide that acts as the first line of defense against bacterial, viral, and fungal infections. This study aims to determine whether or not PF can regulate the expression of hBD-2 and its possible molecular mechanism in human bronchial epithelial cells (HBECs). Real-time quantitative reverse transcription PCR showed that PF can enhance the mRNA expression level of hBD-2 in a concentration- and time-dependent manner in HBECs. Further studies demonstrated that the mRNA and protein expression levels of hBD-2 were attenuated by the p38 mitogen-activated protein kinase (p38 MAPK) inhibitor SB203580, the extracellular signal-regulated kinase (ERK) inhibitor PD98059, and the nuclear factor kappa B (NF-κB) inhibitor (pyrrolidine dithiocarbamate (PDTC)). The phosphorylation of p38 MAPK, ERK, and c-Jun N-terminal kinase was detected by Western blot analysis, and the NF-κB translocation of 16HBECs after PF treatment was analyzed by immunofluorescence. These results support that PF upregulates hBD-2 expression in HBECs through the p38 MAPK, ERK, and NF-κB signaling pathways. These findings provide a new pharmacological mechanism of PF for the treatment of microbial infections by strengthening epithelial antimicrobial barriers.
Assuntos
Glucosídeos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Monoterpenos/farmacologia , NF-kappa B/biossíntese , Mucosa Respiratória/metabolismo , beta-Defensinas/biossíntese , Proteínas Quinases p38 Ativadas por Mitógeno/biossíntese , Linhagem Celular Transformada , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Paeonia , Mucosa Respiratória/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologiaRESUMO
Host defense peptides (HDP) have both microbicidal and immunomodulatory properties. Specific induction of endogenous HDP synthesis has emerged as a novel approach to antimicrobial therapy. Cyclic adenosine monophosphate (cAMP) and butyrate have been implicated in HDP induction in humans. However, the role of cAMP signaling and the possible interactions between cAMP and butyrate in regulating HDP expression in other species remain unknown. Here we report that activation of cAMP signaling induces HDP gene expression in chickens as exemplified by ß-defensin 9 (AvBD9). We further showed that, albeit being weak inducers, cAMP agonists synergize strongly with butyrate or butyrate analogs in AvBD9 induction in macrophages and primary jejunal explants. Additionally, oral supplementation of forskolin, an adenylyl cyclase agonist in the form of a Coleus forskohlii extract, was found to induce AvBD9 expression in the crop of chickens. Furthermore, feeding with both forskolin and butyrate showed an obvious synergy in triggering AvBD9 expression in the crop and jejunum of chickens. Surprisingly, inhibition of the MEK-ERK mitogen-activated protein kinase (MAPK) pathway augmented the butyrate-FSK synergy, whereas blocking JNK or p38 MAPK pathway significantly diminished AvBD9 induction in chicken macrophages and jejunal explants in response to butyrate and FSK individually or in combination. Collectively, these results suggest the potential for concomitant use of butyrate and cAMP signaling activators in enhancing HDP expression, innate immunity, and disease resistance in both animals and humans.
Assuntos
Butiratos/metabolismo , AMP Cíclico/metabolismo , Imunidade Inata/efeitos dos fármacos , beta-Defensinas/biossíntese , Animais , Peptídeos Catiônicos Antimicrobianos/biossíntese , Células Cultivadas , Galinhas , Coleus , Colforsina/administração & dosagem , Colforsina/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Jejuno , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/metabolismo , Sistema de Sinalização das MAP Quinases , Macrófagos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/metabolismo , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
Mastitis, defined as inflammation of the mammary gland, is an infectious disease with a major economic influence on dairy industry. Staphylococcus aureus is a common gram-positive pathogen that frequently causes subclinical, chronic infection of the mammary gland in dairy cows. Farrerol, a traditional Chinese medicine isolated from rhododendron, has been shown to have anti-bacterial activity. However, the effect of farrerol on S. aureus infection in mammary epithelium has not been studied in detail. The aim of this study was to investigate the effect of farrerol on the invasion of bovine mammary epithelial cells (bMEC) by S. aureus. The expression of antimicrobial peptide genes by bMEC were assessed in the presence or absence of S. aureus infection. Our results demonstrated that farrerol (4-16 µg/ml) reduced > 55% the internalization of S. aureus into bMEC. We also found that farrerol was able to down-regulate the mRNA expression of tracheal antimicrobial peptide (TAP) and bovine neutrophil ß-defensin 5 (BNBD5) in bMEC infected with S. aureus. The Nitric oxide (NO) production of bMEC after S. aureus stimulation was decreased by farrerol treatment. Furthermore, farrerol treatment suppressed S. aureus-induced NF-κB activation in bMEC. These results demonstrated that farrerol modulated TAP and BNBD5 gene expression in mammary gland, enhances bMEC defense against S. aureus infection and could be useful in protection against bovine mastitis.
Assuntos
Anti-Infecciosos/farmacologia , Cromonas/farmacologia , Mastite Bovina/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Animais , Peptídeos Catiônicos Antimicrobianos/biossíntese , Bovinos , Ativação Enzimática , Células Epiteliais/citologia , Células Epiteliais/microbiologia , Feminino , Expressão Gênica/efeitos dos fármacos , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/microbiologia , Medicina Tradicional Chinesa , NF-kappa B/metabolismo , Óxido Nítrico/biossíntese , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , beta-Defensinas/biossínteseRESUMO
The intestinal mucosa is constantly exposed to a variety of microbial species including commensals and pathogens, the latter leaving the host susceptible to infection. Antimicrobial peptides (AMP) are an important part of the first line of defense at mucosal surfaces. Human ß-defensins (HBD) are AMP expressed by colonic epithelial cells, which act as broad spectrum antimicrobials. This study explored the direct and indirect effects of green kiwifruit (KF) on human ß-defensin 1 and 2 (HBD-1 and 2) production by epithelial cells. In vitro digestion of KF pulp consisted of a simulated gastric and duodenal digestion, followed by colonic microbial fermentation using nine human faecal donors. Fermenta from individual donors was sterile filtered and independently added to epithelial cells prior to analysis of HBD protein production. KF products obtained from the gastric and duodenal digestion had no effect on the production of HBD-1 or 2 by epithelial cells, demonstrating that KF does not contain substances that directly modulate defensin production. However, when the digested KF products were further subjected to in vitro colonic fermentation, the fermentation products significantly up-regulated HBD-1 and 2 production by the same epithelial cells. We propose that this effect was predominantly mediated by the presence of short-chain fatty acids (SCFA) in the fermenta. Exposure of cells to purified SCFA confirmed this and HBD-1 and 2 production was up-regulated with acetate, propionate and butyrate. In conclusion, in vitro colonic fermentation of green kiwifruit digest appears to prime defense mechanisms in gut cells by enhancing the production of antimicrobial defensins.
Assuntos
Actinidia , Anti-Infecciosos/metabolismo , Colo/efeitos dos fármacos , Frutas , Mucosa Intestinal/efeitos dos fármacos , Preparações de Plantas/farmacologia , beta-Defensinas/biossíntese , Adulto , Colo/metabolismo , Colo/microbiologia , Duodeno/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Feminino , Fermentação , Mucosa Gástrica/metabolismo , Células HT29 , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Masculino , Pessoa de Meia-Idade , Preparações de Plantas/metabolismo , Regulação para CimaRESUMO
Andrographis paniculata (Burm. f) Nees is a traditional herbal medicine for the treatment of infection and inflammation in China. Andrographolide (andro) is one of the major components. Human ß-defensin-2 (hBD-2) is an inducible antimicrobial peptide that plays an important role in innate immunity. The present study aimed to investigate the effect of andro on upregulation of hBD-2 and the key signaling pathways involved in andro-induced hBD-2 expression. Real-time reverse transcription - PCR and Western blot assays showed that andro (1.0-10 µmol/L) can upregulate the expression of hBD-2 in a dose-dependent manner. Further studies suggested that hBD-2 mRNA and protein expression in responsive to andro were attenuated by pretreatment with SB203580 (an inhibitor of p38 mitogen-activated protein kinase (p38 MAPK)), MG-132 (an inhibitor of nuclear factor κB (NF-κB)), and an NF-κB activator inhibitor, but not by an inhibitor of ERK (PD98059) or by an inhibitor of JNK(SP600125). Moreover, we found that a second p38 MAPK inhibitor (SB202190) significantly blocked andro-mediated hBD-2 induction in SPC-A-1 lung epithelial cells. Finally, the p-c-Jun transcription factor activity assay also showed that AP-1 activity was induced by andro compared with the untreated group. We conclude that andro may exert its antimicrobial effects by upregulating the expression of hBD-2 through the p38 MAPK and NF-κB pathway.
Assuntos
Anti-Infecciosos/farmacologia , Diterpenos/farmacologia , NF-kappa B/metabolismo , beta-Defensinas/biossíntese , beta-Defensinas/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , NF-kappa B/genética , RNA Mensageiro/genética , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos , beta-Defensinas/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genéticaRESUMO
Skin wounds usually heal without major infections, although the loss of the mechanical epithelial barrier exposes the tissue to various bacteria. One reason may be the expression of antimicrobial peptides (AMP) of which some [human beta-defensins (hBD) and LL-37] were recently shown to support additionally certain steps of wound healing. There are no studies which have compared expression patterns of different classes of AMP in chronic wounds. The aim of our study was therefore to analyse the expression profile of hBD-2, hBD-3, LL-37, psoriasin and RNase 7 by immunohistochemistry from defined wound margins of chronic venous ulcers. We detected a strong induction of psoriasin and hBD-2 in chronic wounds in comparison with healthy skin. Except for stratum corneum, no expression of RNase 7 and LL-37 was detected in the epidermis while expression of hBD-3 was heterogeneous. Bacterial swabs identified Staphylococcus aureus and additional bacterial populations, but no association between colonization and AMP expression was found. The differential expression of AMP is noteworthy considering the high bacterial load of chronic ulcers. Clinically, supplementation of AMP with the capability to enhance wound healing besides restricting bacterial overgrowth could present a physiological support for treatment of disturbed wound healing.
Assuntos
Peptídeos Catiônicos Antimicrobianos/biossíntese , Ferimentos e Lesões/metabolismo , Idoso , Peptídeos Catiônicos Antimicrobianos/genética , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Ribonucleases/biossíntese , Proteína A7 Ligante de Cálcio S100 , Proteínas S100/biossíntese , Infecções Cutâneas Estafilocócicas/metabolismo , Infecções Cutâneas Estafilocócicas/microbiologia , Úlcera Varicosa/metabolismo , Úlcera Varicosa/microbiologia , Ferimentos e Lesões/genética , Ferimentos e Lesões/microbiologia , beta-Defensinas/biossíntese , CatelicidinasAssuntos
Farmacorresistência Bacteriana Múltipla , Ácido Glicirrízico/uso terapêutico , Infecções por Pseudomonas/tratamento farmacológico , Infecção dos Ferimentos/tratamento farmacológico , Animais , Queimaduras/complicações , Avaliação Pré-Clínica de Medicamentos , Humanos , Imunidade Inata , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Camundongos , Infecções por Pseudomonas/etiologia , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/efeitos dos fármacos , Infecção dos Ferimentos/etiologia , Infecção dos Ferimentos/microbiologia , beta-Defensinas/biossínteseRESUMO
The decreased production of antimicrobial peptides in tissues surrounding the burn sites has been described in patients with severe burn injury. Small numbers of Pseudomonas aeruginosa spread easily to the whole body of burn mice when infected at burn site tissues. Gr-1(+)CD11b(+) cells, demonstrated in tissues surrounding the burn site, are inhibitory on the production of antimicrobial peptides by EK. In this paper, the decreased production of antimicrobial peptides by EK influenced by Gr-1(+)CD11b(+) cells was shown to be restored by glycyrrhizin. CCL2 and IL-10 were determined to be effector soluble factors for the suppressor activities of Gr-1(+)CD11b(+) cells on antimicrobial peptide production by EK. However, Gr-1(+)CD11b(+) cells, which were treated previously with glycyrrhizin, did not produce these soluble factors. Also, sepsis stemming from P. aeruginosa burn-site infection was not demonstrated in burn mice treated with glycyrrhizin. These results suggest that through the improved production of antimicrobial peptides in tissues surrounding the burn area, sepsis stemming from P. aeruginosa wound infection is controllable by glycyrrhizin in severely burned mice.
Assuntos
Queimaduras/complicações , Ácido Glicirrízico/uso terapêutico , Queratinócitos/efeitos dos fármacos , Infecções por Pseudomonas/prevenção & controle , Infecção dos Ferimentos/prevenção & controle , beta-Defensinas/biossíntese , Animais , Queimaduras/microbiologia , Quimiocina CCL2/fisiologia , Avaliação Pré-Clínica de Medicamentos , Farmacorresistência Bacteriana Múltipla , Ácido Glicirrízico/farmacologia , Humanos , Interleucina-10/fisiologia , Interleucinas/análise , Queratinócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/etiologia , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/etiologia , Infecção dos Ferimentos/microbiologia , beta-Defensinas/genéticaRESUMO
BACKGROUND: In previous studies, distinct immunological abnormalities have been reported in localized scleroderma (LS). Several pro-inflammatory cytokines have been demonstrated at increased levels in sera of patients with LS in parallel with disease activity. Human beta-defensins (hBDs) are peptides with antimicrobial activity, but have been also shown to be implicated in tissue injury, scarring and wound healing. hBD expression in LS, a condition resembling pathological scarring due to excessive stimulation of matrix synthesis and fibroblast activation, has so far not been investigated. Ultraviolet (UV) A1 phototherapy, the most recent advance in the treatment of LS, targets T-cell dermal inflammatory infiltrates via induction of various cytokines and soluble factors besides well-known effects on collagen metabolism. OBJECTIVES: We sought to investigate the effects of UVA1 on the expression and modulation of hBDs and several pro-inflammatory cytokines in LS. METHODS: UVA1 phototherapy was performed five times weekly for 8 weeks resulting in a total of 40 treatment sessions (single dose 20 J cm2, cumulative dose 800 J cm2). hBD-1, hBD-2 and hBD-3 mRNA as well as tumour necrosis factor-alpha, transforming growth factor-beta, interleukin (IL) -2, IL-4, IL-6 and IL-8 mRNA expression were determined by quantitative real-time reverse transcription-polymerase chain reaction in lesional and unaffected skin of patients with LS. RESULTS: Skin status markedly improved in all 14 patients, resulting in a significant reduction of the clinical score from baseline to the end of treatment. hBD-1, hBD-2 and hBD-3 mRNA levels were higher in lesional skin compared with unaffected skin and skin from healthy volunteers. Following UVA1 phototherapy, hBD-1 mRNA decreased in lesional, but not in unaffected skin. hBD-3 mRNA levels significantly decreased after UVA1 in lesional skin, whereas an increase of hBD-3 was observed in unaffected skin. IL-6 and IL-8 mRNA levels were significantly elevated in lesional skin and significantly decreased after UVA1 irradiation, whereas mRNA for both cytokines remained unchanged in irradiated unaffected skin. The decrease of hBD-1, hBD-3, IL-6 and IL-8 mRNA paralleled the extent of disease and response to UVA1 phototherapy. CONCLUSIONS: hBDs and IL-6 and IL-8, cytokines with pivotal importance in sclerotic skin diseases, are downregulated by UVA1 in the lesional skin of patients with LS. Their pathogenetic relevance with respect to clinical improvement needs further investigation.
Assuntos
Regulação para Baixo/efeitos da radiação , Interleucina-6/biossíntese , Interleucina-8/biossíntese , Esclerodermia Localizada/radioterapia , Terapia Ultravioleta , beta-Defensinas/biossíntese , Adulto , Feminino , Humanos , Interleucina-6/genética , Interleucina-8/genética , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Esclerodermia Localizada/imunologia , Índice de Gravidade de Doença , Pele/imunologia , Resultado do Tratamento , beta-Defensinas/genéticaRESUMO
The hormonal form of vitamin D(3), 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)), is an immune system modulator and induces expression of the TLR coreceptor CD14. 1,25(OH)(2)D(3) signals through the vitamin D receptor, a ligand-stimulated transcription factor that recognizes specific DNA sequences called vitamin D response elements. In this study, we show that 1,25(OH)(2)D(3) is a direct regulator of antimicrobial innate immune responses. The promoters of the human cathelicidin antimicrobial peptide (camp) and defensin beta2 (defB2) genes contain consensus vitamin D response elements that mediate 1,25(OH)(2)D(3)-dependent gene expression. 1,25(OH)(2)D(3) induces antimicrobial peptide gene expression in isolated human keratinocytes, monocytes and neutrophils, and human cell lines, and 1,25(OH)(2)D(3) along with LPS synergistically induce camp expression in neutrophils. Moreover, 1,25(OH)(2)D(3) induces corresponding increases in antimicrobial proteins and secretion of antimicrobial activity against pathogens including Pseudomonas aeruginosa. 1,25(OH)(2)D(3) thus directly regulates antimicrobial peptide gene expression, revealing the potential of its analogues in treatment of opportunistic infections.