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1.
PLoS One ; 19(2): e0297080, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38408073

RESUMO

BACKGROUND: Hair loss/thinning is a common side effect of tamoxifen in estrogen receptor (ER) positive breast cancer therapy. Some nutraceuticals known to promote hair growth are avoided during breast cancer therapy for fear of phytoestrogenic activity. However, not all botanical ingredients have similarities to estrogens, and in fact, no information exists as to the true interaction of these ingredients with tamoxifen. Therefore, this study sought to ascertain the effect of nutraceuticals (+/- estrogen/tamoxifen), on proliferation of breast cancer cells and the relative expression of ERα/ß. METHODS: Kelp, Astaxanthin, Saw Palmetto, Tocotrienols, Maca, Horsetail, Resveratrol, Curcumin and Ashwagandha were assessed on proliferation of MCF7, T47D and BT483 breast cancer cell lines +/- 17ß-estradiol and tamoxifen. Each extract was analysed by high performance liquid chromatography (HPLC) prior to use. Cellular ERα and ERß expression was assessed by qRT-PCR and western blot. Changes in the cellular localisation of ERα:ERß and their ratio following incubation with the nutraceuticals was confirmed by immunocytochemistry. RESULTS: Estradiol stimulated DNA synthesis in three different breast cancer cell lines: MCF7, T47D and BT483, which was inhibited by tamoxifen; this was mirrored by a specific ERa agonist in T47D and BT483 cells. Overall, nutraceuticals did not interfere with tamoxifen inhibition of estrogen; some even induced further inhibition when combined with tamoxifen. The ERα:ERß ratio was higher at mRNA and protein level in all cell lines. However, incubation with nutraceuticals induced a shift to higher ERß expression and a localization of ERs around the nuclear periphery. CONCLUSIONS: As ERα is the key driver of estrogen-dependent breast cancer, if nutraceuticals have a higher affinity for ERß they may offer a protective effect, particularly if they synergize and augment the actions of tamoxifen. Since ERß is the predominant ER in the hair follicle, further studies confirming whether nutraceuticals can shift the ratio towards ERß in hair follicle cells would support a role for them in hair growth. Although more research is needed to assess safety and efficacy, this promising data suggests the potential of nutraceuticals as adjuvant therapy for hair loss in breast cancer patients receiving endocrine therapy.


Assuntos
Neoplasias da Mama , Tamoxifeno , Humanos , Feminino , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico , Neoplasias da Mama/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Estradiol/farmacologia , Estrogênios/farmacologia , Células MCF-7 , Suplementos Nutricionais , Alopecia/tratamento farmacológico , Cabelo/metabolismo , Linhagem Celular Tumoral , Proliferação de Células
3.
Nutrients ; 12(11)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33217935

RESUMO

Nutraceuticals, natural dietary and botanical supplements offering health benefits, provide a basis for complementary and alternative medicine (CAM). Use of CAM by healthy individuals and patients with medical conditions is rapidly increasing. For the majority of breast cancer patients, treatment plans involve 5-10 yrs of endocrine therapy, but hair loss/thinning is a common side effect. Many women consider this significant, severely impacting on quality of life, even leading to non-compliance of therapy. Therefore, nutraceuticals that stimulate/maintain hair growth can be proposed. Although nutraceuticals are often available without prescription and taken at the discretion of patients, physicians can be reluctant to recommend them, even as adjuvants, since potential interactions with endocrine therapy have not been fully elucidated. It is, therefore, important to understand the modus operandi of ingredients to be confident that their use will not interfere/interact with therapy. The aim is to improve clinical/healthcare outcomes by combining specific nutraceuticals with conventional care whilst avoiding detrimental interactions. This review presents the current understanding of nutraceuticals beneficial to hair wellness and outcomes concerning efficacy/safety in breast cancer patients. We will focus on describing endocrine therapy and the role of estrogens in cancer and hair growth before evaluating the effects of natural ingredients on breast cancer and hair growth.


Assuntos
Alopecia/induzido quimicamente , Alopecia/prevenção & controle , Inibidores da Aromatase/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Suplementos Nutricionais , Tamoxifeno/efeitos adversos , Antineoplásicos Hormonais/efeitos adversos , Antineoplásicos Hormonais/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Terapias Complementares/métodos , Feminino , Humanos , Tamoxifeno/uso terapêutico
4.
J Cosmet Sci ; 63(1): 1-13, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22487447

RESUMO

Vitamin B5 and its derivatives are well known in personal care applications and are often used in wound healing and soothing compositions. However, little is known about the biochemical pathways involved. A better knowledge of these pathways would help to understand some of the mechanisms of action and suggest further applications. We have investigated the transformation of D-panthenyl triacetate (PTA) into D-panthenol (PAN) and its skin diffusion on human volunteers by Raman spectroscopy. Additionally, we have utilized human skin biopsies and quantitative RT-PCR to demonstrate the effect of PTA compared to PAN on 27 metabolic markers when introduced at 2% in a cosmetic emulsion. Then we conducted a double-blind clinical study to measure the effect of PTA compared to PAN on wound healing, measured by transepidermal water loss (TEWL), when incorporated at 3% in a cosmetic emulsion. Results show de-acetylation of PTA into PAN and an increased activity of PTA compared to PNA over time in the skin. Metabolic marker analysis demonstrates stimulation of energetic pathways such as glycolysis and the citric acid cycle, but also of synthesis pathways such as isoprenoids and lipid synthesis, by PTA and PAN. Finally, the clinical study demonstrates a statistically significant effect by PTA on wound healing after 72 hours when compared to a saline treatment. Statistical significance was not achieved by PAN or a placebo treatment. Due to the differences between PTA and PAN action, different applications in personal care products can be suggested. Moreover, PTA seems more effective than PAN for a long-lasting wound healing action.


Assuntos
Acetatos/farmacologia , Ácido Pantotênico/análogos & derivados , Ácido Pantotênico/farmacologia , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Acetatos/farmacocinética , Adulto , Biotransformação , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Pantotênico/farmacocinética , Reação em Cadeia da Polimerase em Tempo Real , Pele/metabolismo , Análise Espectral Raman
5.
Shock ; 26(3): 296-301, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16912656

RESUMO

A mouse model of staphylococcal sepsis was used to evaluate the efficacy of RNAIII-inhibiting peptide (RIP) combined with the cathelicidin BMAP-28. Preliminary in vitro studies showed that both peptides, alone or combined, were able to inhibit the lipoteichoic acid-induced production of tumor necrosis factor alpha and nitric oxide by RAW 264.7 cells. For in vivo experiments, the main outcome measures were lethality, quantitative blood cultures, and detection of tumor necrosis factor alpha and interleukin 6 plasma levels. BALB/c mice were injected i.v. with 2.0 x 10(6) colony-forming units of live Staphylococcus aureus ATCC 25923 or with 5.0 x 10(8) heat-killed cells of the same strain. All animals were randomized to receive i.v. isotonic sodium chloride solution, 10-mg/kg RIP, alone or in combination with 2-mg/kg BMAP-28, 7-mg/kg imipenem, or 7-mg/kg vancomycin, immediately and at 6 hours after bacterial challenge. In in vivo experiments performed with live bacteria, all compounds reduced lethality rates and bacteremia when compared with controls. In general, combined-treated groups had significantly lower bacteremia when compared with single-treated groups. Lowest lethality rates and bacteremia were obtained when RIP was administered in combination with BMAP-28 or vancomycin. In the experiments performed using heat-killed organisms, only BMAP-28 demonstrated significant efficacy on lethality rates and cytokines plasma levels when compared with controls. RIP combined with BMAP-28 exhibited the highest efficacy on all main outcome measurements. These data were observed on both immediate and delayed treatments. These results highlight the capacity of RIP and BMAP-28 to reduce the septic effects of bacterial cell components and exotoxins, and suggest their potential use in the treatment of severe staphylococcus-associated sepsis.


Assuntos
Oligopeptídeos/uso terapêutico , Proteínas/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Linhagem Celular Tumoral , Modelos Animais de Doenças , Quimioterapia Combinada , Interleucina-6/sangue , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Oligopeptídeos/farmacologia , Proteínas/farmacologia , Infecções Estafilocócicas/sangue , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Análise de Sobrevida , Ácidos Teicoicos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
6.
J Infect Dis ; 193(2): 180-6, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16362881

RESUMO

BACKGROUND: Medical devices used in clinical practice are often associated with biofilm-associated staphylococcal infections. METHODS: An in vitro antibiotic susceptibility assay of Staphylococcus aureus biofilms using 96-well polystyrene tissue-culture plates was performed to test the effects of RNAIII-inhibiting peptide (RIP), ciprofloxacin, imipenem, and vancomycin. Efficacy studies were performed using a rat model of central venous catheter (CVC)-associated infection. Twenty-four hours after implantation, the catheters were filled with RIP (1 mg/mL). Thirty minutes later, rats were challenged, via the CVC, with 1.0 x 10(6) cfu of S. aureus strain Smith diffuse. The antibiotic-lock technique was begun 24 h later. RESULTS: Minimum inhibitory concentrations of antibiotics in biofilms were at least 4-fold higher than those against the freely growing planktonic cells. When they were first treated with RIP, the cells in biofilms became as susceptible to antibiotics as did planktonic cells. These data were confirmed by the in vivo studies. In particular, when CVCs were treated with both RIP and antibiotics, the biofilm bacterial load was further reduced to 1 x 10(1) cfu/mL, and bacteremia was not detected, suggesting that there was 100% elimination of bacteremia and a 6 log10 reduction in biofilm bacterial load. CONCLUSION: RIP significantly reduces bacterial load and enhances the effect of antibiotics in the treatment of CVC-associated S. aureus infections.


Assuntos
Antibacterianos/farmacologia , Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/microbiologia , Oligopeptídeos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/uso terapêutico , Bacteriemia/prevenção & controle , Biofilmes/efeitos dos fármacos , Ciprofloxacina/farmacologia , Ciprofloxacina/uso terapêutico , Quimioterapia Combinada , Imipenem/farmacologia , Imipenem/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Oligopeptídeos/uso terapêutico , Ratos , Vancomicina/farmacologia , Vancomicina/uso terapêutico
7.
Clin Orthop Relat Res ; (437): 48-54, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16056025

RESUMO

Staphylococcus aureus and Staphylococcus epidermidis associated with implantable medical devices, are often difficult to treat with conventional antimicrobials. Formation of a biofilm and subsequent production of toxins are two distinct mechanisms considered important in foreign body infections. Staphylococcal virulence is caused by a complex regulatory process, which involves cell-to-cell communication through the release and response to chemical signals in a process known as quorum sensing. We explored the possibility of preventing infections by interfering with biofilm formation and toxin production using the quorum sensing inhibitor ribonucleic-acid-III-inhibiting peptide. In our studies ribonucleic-acid-III-inhibiting peptide prevented graft-associated infections caused by all species of staphylococci tested so far, including methicillin resistant S. aureus and S. epidermidis. Ribonucleic-acid-III-inhibiting peptide also enhances the effects of antibiotics and cationic peptides in the clearance of normally recalcitrant biofilm infections. Ribonucleic-acid-III-inhibiting peptide is nontoxic, highly stable, and no resistant strains have been found so far, suggesting that ribonucleic-acid-III-inhibiting peptide may be used to coat medical devices or used systemically to prevent infections. When the target of ribonucleic-acid-III activating protein activity is disrupted, biofilm formation is reduced under flow and static conditions and genes important for toxin production or biofilm formation are down-regulated. These in vitro data help explain why ribonucleic-acid-III-inhibiting peptide seems to be effective in preventing staphylococcal infections.


Assuntos
Biofilmes/efeitos dos fármacos , Oligopeptídeos/uso terapêutico , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Estafilocócicas/prevenção & controle , Staphylococcus epidermidis/patogenicidade , Animais , Proteínas de Bactérias/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Injeções Intraperitoneais , Masculino , Oligopeptídeos/administração & dosagem , Infecções Relacionadas à Prótese/microbiologia , Proteínas de Ligação a RNA/efeitos dos fármacos , Proteínas de Ligação a RNA/metabolismo , Ratos , Ratos Wistar , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/metabolismo , Fatores de Transcrição/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Resultado do Tratamento , Virulência
8.
Peptides ; 26(2): 169-75, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15629527

RESUMO

RNAIII-inhibiting peptide (RIP, YSPWTNF-NH2) is a quorum-sensing peptide inhibitor that prevents Staphylococcus aureus toxin production and biofilm formation. A mouse sepsis model was used to test the efficacy of RIP alone or in combination with conventional antibiotics in suppressing S. aureus-induced sepsis. Mice were injected intravenously with 3.0x10(6)CFU of S. aureus ATCC 25923 or with 3.0x10(6)CFU of S. aureus strain Smith diffuse. All animals were randomized to receive intravenously isotonic sodium chloride solution as a control, or 20 mg/kg RIP alone or combined with 20 mg/kg cefazolin, 10 mg/kg imipenem, or 10 mg/kg vancomycin immediately or 6 h after bacterial challenge. Main outcome measures were bacteremia and lethality. All compounds reduced lethality when compared to controls. Although, in general combined-treated groups had significant lower bacterial counts when associated to singly-treated groups only the combination between RIP and vancomycin with respect to cefazolin gave a statistically significant decrease in the lethality rate. Lowest lethality rates (10%) and bacteremia (<10(2)CFU/ml) were obtained when RIP was administered in combination with vancomycin. Because RIP can be synergistic with current antibiotic therapies and help to reduce S. aureus exotoxins production, it can be considered a promising agent to associate with antibiotics for further clinical research into treatment of sepsis.


Assuntos
Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Sepse/tratamento farmacológico , Sepse/patologia , Infecções Estafilocócicas/tratamento farmacológico , Animais , Bacteriemia , Cefazolina/farmacologia , Cefazolina/uso terapêutico , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Sinergismo Farmacológico , Imipenem/farmacologia , Imipenem/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oligopeptídeos/efeitos adversos , Distribuição Aleatória , Sensibilidade e Especificidade , Sepse/microbiologia , Infecções Estafilocócicas/mortalidade , Staphylococcus aureus/efeitos dos fármacos , Fatores de Tempo , Vancomicina/farmacologia , Vancomicina/uso terapêutico
9.
J Infect Dis ; 190(2): 318-20, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15216467

RESUMO

Staphylococcus aureus and S. epidermidis are major causes of infection related to biofilm formed on indwelling medical devices. Such infections are common causes of morbidity and mortality and, because of biofilm resistance to antibiotics, are difficult to treat. The RNAIII-inhibiting peptide (RIP) (YSPWTNF-NH2) inhibits the pathogenesis of staphylococci by disrupting bacterial cell-cell communication (known as "quorum sensing"). Using a vascular-graft rat model, we show that RIP, applied locally and systemically, can completely inhibit drug-resistant S. aureus and S. epidermidis biofilms. The present study provides the first direct demonstration that interfering with cell-cell communication by use of a quorum-sensing inhibitor can eliminate medical device-associated staphylococcal infections. We suggest that medical devices could be coated with RIP to prevent infections, including those by antibiotic-resistant staphylococcal strains.


Assuntos
Oligopeptídeos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Animais , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Modelos Animais de Doenças , Farmacorresistência Bacteriana , Equipamentos e Provisões/microbiologia , Oligopeptídeos/administração & dosagem , Ratos , Infecções Estafilocócicas/microbiologia
10.
Skin Res Technol ; 9(4): 331-8, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14641883

RESUMO

BACKGROUND/PURPOSE: Switzerland has one of the highest rates of skin diseases and particularly skin cancer, in Europe. Skin elastosis, roughness and atopy are also frequent. High UV exposure and prevalence of light skin individuals could be the cause. Valais, in Southern Switzerland, is a mountain region with elevated sun irradiation and low air humidity, an ideal location to study the effect of the environment and life style on skin biophysical characteristics. The purpose of the study was to measure skin biophysical parameters non-invasively on healthy subjects living in Valais, and to correlate the measures with their life style. METHODS: One hundred and ten women were examined between October 2001 and February 2002. Measures of skin hydration, sebum content, pH and visco-elasticity were taken in a closed environment with constant temperature and controlled air humidity, utilizing commercially available non-invasive devices. Subjects were interviewed using a questionnaire and data on personal traits and life style were collected. Correlations between subject's skin parameters and life style were statistically examined. RESULTS: On average we observed low values of skin capacitance that identify subjects with dry skin. Measures of skin visco-elasticity ratios were also particularly low, while skin pH and sebum content were in the normal range. Age was correlated with a decrease of skin elasticity and sebum content, but there was no correlation with hydration or pH. CONCLUSIONS: We confirm, as reported in other studies, the effect of age on skin elasticity and sebum content and we identify, for the first time, a region with a population characterized by particularly low levels of skin hydration and skin visco-elasticity. Although people examined were free of skin diseases, we believe that protection from the sun and treatment of skin with hydrating products need to be emphasized as a prevention strategy, in regions such as Valais, with high sun irradiation and low humidity.


Assuntos
Estilo de Vida , Fenômenos Fisiológicos da Pele , Adolescente , Adulto , Idoso , Feminino , Humanos , Concentração de Íons de Hidrogênio , Pessoa de Meia-Idade , Valores de Referência , Sebo/metabolismo , Pele/efeitos da radiação , Suíça/epidemiologia , Raios Ultravioleta
11.
Circulation ; 108(6): 767-71, 2003 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-12885754

RESUMO

BACKGROUND: Bacteria that adhere to implanted medical devices play an important role in industry and in modern medicine. Staphylococci are among the most common pathogens that cause biomaterial infections. Vascular prosthetic graft infection is one of the most feared complications that the vascular surgeon treats, frequently resulting in prolonged hospitalization, organ failure, amputation, and death. A rat model was used to investigate the topical efficacies of temporin A and the quorum-sensing inhibitor RNAIII-inhibiting protein (RIP) as prophylactic agents of vascular prosthetic graft infections caused by Staphylococcus aureus and Staphylococcus epidermidis with intermediate resistance to glycopeptides. METHODS AND RESULTS: Graft infections were established in the back subcutaneous tissue of adult male Wistar rats by implantation of Dacron prostheses 1 cm2 followed by topical inoculation with 2x10(7) colony-forming units of bacterial strains. The study included, for each staphylococcal strain, a control group (no graft contamination), a contaminated group that did not receive antibiotic prophylaxis, and 6 contaminated groups that received grafts soaked with temporin A, RIP, rifampin, temporin A plus RIP, RIP plus rifampin, or temporin A plus RIP. The infection was evaluated by quantitative agar culture. When tested alone, temporin A and RIP showed comparable efficacies, and their efficacies were significantly higher than that of rifampin against both strains. All combinations showed efficacies significantly higher than that of each single compound. The combinations of temporin A and RIP exerted the strongest antistaphylococcal efficacies, eliminating infection by 100%. CONCLUSIONS: The results of the present study make these molecules potentially useful for antimicrobial chemoprophylaxis in vascular surgery.


Assuntos
Implantes Experimentais/efeitos adversos , Oligopeptídeos/administração & dosagem , Proteínas/administração & dosagem , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Tela Subcutânea/patologia , Administração Tópica , Animais , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Resistência Microbiana a Medicamentos , Quimioterapia Combinada/administração & dosagem , Glicopeptídeos/farmacologia , Implantes Experimentais/microbiologia , Masculino , Testes de Sensibilidade Microbiana , Oligopeptídeos/química , Polietilenotereftalatos/química , Proteínas/química , Ratos , Ratos Wistar , Rifampina/farmacologia , Infecções Cutâneas Estafilocócicas/microbiologia , Infecções Cutâneas Estafilocócicas/patologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/patogenicidade , Tela Subcutânea/microbiologia , Resultado do Tratamento , Vancomicina/farmacologia , Resistência a Vancomicina
12.
Antimicrob Agents Chemother ; 47(6): 1979-83, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12760879

RESUMO

Staphylococcus aureus is a prevalent cause of bacterial infections associated with indwelling medical devices. RNA III inhibiting peptide (RIP) is known to inhibit S. aureus pathogenesis by disrupting quorum-sensing mechanisms. RIP was tested in the present study for its ability to inhibit S. aureus biofilm formation in a rat Dacron graft model. The activity of RIP was synergistic with those of antibiotics for the complete prevention of drug-resistant S. aureus infections.


Assuntos
Biofilmes/crescimento & desenvolvimento , Oligopeptídeos/farmacologia , Próteses e Implantes/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Animais , Antibacterianos/farmacologia , Antibioticoprofilaxia , Biofilmes/efeitos dos fármacos , Comunicação Celular/efeitos dos fármacos , Contagem de Colônia Microbiana , Sinergismo Farmacológico , Masculino , Testes de Sensibilidade Microbiana , Polietilenotereftalatos , Ratos , Ratos Wistar
13.
J Infect Dis ; 187(4): 625-30, 2003 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-12599079

RESUMO

Staphylococcus epidermidis is a frequent cause of infections associated with foreign bodies and indwelling medical devices. The bacteria are capable of surviving antibiotic treatment through encapsulation into biofilms. RNAIII-inhibiting peptide (RIP) is a heptapeptide that inhibits S. aureus pathogenesis by disrupting quorum-sensing mechanisms. In this study, RIP inhibited drug-resistant S. epidermidis biofilm formation through a mechanism similar to that evidenced for S. aureus. RIP is synergistic with antibiotics in eliminating 100% of graft-associated in vivo S. epidermidis infections, which suggests that RIP may be used to coat medical devices to prevent staphylococcal infections. Disruption of cell-cell communication can prevent infections associated with antibiotic-resistant strains.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias , Oligopeptídeos/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal , Animais , Aderência Bacteriana , Biofilmes/crescimento & desenvolvimento , Linhagem Celular , Resistência a Medicamentos , Humanos , Masculino , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus epidermidis/metabolismo
14.
Circulation ; 105(14): 1686-92, 2002 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-11940548

RESUMO

BACKGROUND: Although inhibition of neointimal hyperplasia by cell cycle gene blockade therapy results in improved endothelial cell function in experimental vein grafts, little is known either about endothelial healing immediately after vein grafting or about the effect of this therapy on the healing process. METHODS AND RESULTS: Scanning electron microscopy demonstrated an immediate decrease in vein graft endothelial cell density associated with vein graft wall stretch, followed by a return to baseline by postoperative day 3. En face detection of bromodeoxyuridine incorporation confirmed a rapid endothelial proliferation by 48 hours. Despite inhibition of underlying vascular smooth muscle cell proliferation, E2F decoy oligonucleotide did not inhibit either endothelial bromodeoxyuridine incorporation or the return to baseline cell density. This differential response to E2F decoy was also observed in human umbilical vein endothelial cell culture, which resisted the E2F decoy inhibition of cell growth that was observed in human umbilical artery smooth muscle cells, despite evidence for nuclear localized delivery of the oligonucleotide into both cell types. Furthermore, the reduction of E2F binding activity seen in a nuclear gel shift assay of cultured smooth muscle cells was not observed in endothelial cells. CONCLUSIONS: These results suggest a burst of graft endothelial cell proliferation that allows a rapid restoration of cell density in the monolayer. Additionally, there is a selective effect of E2F decoy gene therapy on target smooth muscle cells with sparing of this endothelial healing.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Endotélio Vascular/efeitos dos fármacos , Terapia Genética , Oclusão de Enxerto Vascular/prevenção & controle , Veias Jugulares/efeitos dos fármacos , Oligonucleotídeos/administração & dosagem , Animais , Bromodesoxiuridina , Artérias Carótidas/cirurgia , Contagem de Células , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Fatores de Transcrição E2F , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Oclusão de Enxerto Vascular/patologia , Oclusão de Enxerto Vascular/fisiopatologia , Imuno-Histoquímica , Veias Jugulares/patologia , Veias Jugulares/transplante , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Antígeno Nuclear de Célula em Proliferação/biossíntese , Coelhos , Fatores de Transcrição/antagonistas & inibidores , Transfecção , Resultado do Tratamento , Cicatrização/efeitos dos fármacos , Cicatrização/genética
15.
Circulation ; 105(5): 602-7, 2002 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-11827926

RESUMO

BACKGROUND: Ischemia and oxidative stress are the leading mechanisms for tissue injury. An ideal strategy for preventive/protective therapy would be to develop an approach that could confer long-term transgene expression and, consequently, tissue protection from repeated ischemia/reperfusion injury with a single administration of a therapeutic gene. In the present study, we used recombinant adeno-associated virus (rAAV) as a vector for direct delivery of the cytoprotective gene heme oxygenase-1 (HO-1) into the rat myocardium, with the purpose of evaluating this strategy as a therapeutic approach for long-term protection from ischemia-induced myocardial injury. METHODS AND RESULTS: Human HO-1 gene (hHO-1) was delivered to normal rat hearts by intramyocardial injection. AAV-mediated transfer of the hHO-1 gene 8 weeks before acute coronary artery ligation and release led to a dramatic reduction (>75%) in left ventricular myocardial infarction. The reduction in infarct size was accompanied by decreases in myocardial lipid peroxidation and in proapoptotic Bax and proinflammatory interleukin-1beta protein abundance, concomitant with an increase in antiapoptotic Bcl-2 protein level. This suggested that the transgene exerts its cardioprotective effects in part by reducing oxidative stress and associated inflammation and apoptotic cell death. CONCLUSIONS: This study documents the beneficial therapeutic effect of rAAV-mediated transfer, before myocardial injury, of a cytoprotective gene that confers long-term myocardial protection from ischemia/reperfusion injury. Our data suggest that this novel "pre-event" gene transfer approach may provide sustained tissue protection from future repeated episodes of injury and may be beneficial as preventive therapy for patients with or at risk of developing coronary ischemic events.


Assuntos
Terapia Genética/métodos , Heme Oxigenase (Desciclizante)/biossíntese , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/prevenção & controle , Miocárdio/metabolismo , Animais , Apoptose , Vasos Coronários , Citocinas/metabolismo , Citoproteção/efeitos dos fármacos , Dependovirus/genética , Modelos Animais de Doenças , Expressão Gênica , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Heme Oxigenase (Desciclizante)/administração & dosagem , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase-1 , Humanos , Ligadura , Masculino , Proteínas de Membrana , Infarto do Miocárdio/patologia , Miocárdio/patologia , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Tempo , Transgenes/genética
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