RESUMO
IL-1 and TNF-α are always present during wound repair, but their pleiotropic and synergistic effects are incompletely understood. In this work, we evaluated the role of IL-1 in wound repair, and examined whether TNF-α administration impaired scarless wound repair. First, we characterised wound repair in outbred CD-1 mice according to age and sex in an ear punch wound model. Then, we examined the effects of Interleukin 1 receptor antagonist (IL-1ra) and TNF-α placement inside ear wounds by means of loaded Heparin beads in young and middle-aged male and female mice. Wounds in middle-aged females repaired with scarless characteristics, whereas those in young males showed fibrotic scarring. Rather than improving wound repair in young males, IL-1 signalling blockade increased epithelial thickness and IL-1ß and TNF-α expression, and diminished epidermal apoptosis. TNF-α impaired wound repair in middle-aged females, which exhibited acanthosis and overexpression of IL-1, but no change in apoptosis. These findings suggest that this mechanism of epidermal thickening differs from that observed in IL1-ra-treated animals.
Assuntos
Cicatriz/tratamento farmacológico , Proteína Antagonista do Receptor de Interleucina 1/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Regeneração/efeitos dos fármacosRESUMO
Application of polymers cross-linked by gamma irradiation on cutaneous wounds has resulted in the improvement of healing. Chitosan (CH) and poloxamer 407 (P407)-based hydrogels confer different advantages in wound management. To combine the properties of both compounds, a gamma-irradiated mixture of 0.75/25% (w/w) CH and P407, respectively, was obtained (CH-P), and several physical, chemical, and biological analyses were performed. Notably, gamma radiation induced changes in the mixture's thermal behavior, viscosity, and swelling, and exhibited stability at neutral pH. The thermal reversibility provided by P407 and the bacteriostatic effect of CH were maintained. Mice full-thickness wounds treated with CH-P diminished the wound area during the first days. Consequently, with this treatment, increased levels of macrophages, α-SMA, and collagen deposition in wounds were observed, indicating a more mature scar tissue. In conclusion, the new hydrogel CH-P, at physiologic pH, combined the beneficial characteristics of both polymers and produced new properties for wound management.
Assuntos
Materiais Biocompatíveis/química , Hidrogéis/química , Poloxâmero/química , Actinas/metabolismo , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Materiais Biocompatíveis/farmacologia , Varredura Diferencial de Calorimetria , Candida albicans/efeitos dos fármacos , Quitosana/química , Escherichia coli/efeitos dos fármacos , Raios gama , Hidrogéis/efeitos da radiação , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Reologia , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Temperatura , Viscosidade , Cicatrização/efeitos dos fármacosRESUMO
Un estudio fue conducido en 9 centros de control de rabia en la zona metropolitana de la ciudad de México, de enero a julio 2007. Los perros muestreados fueron capturados en las calles. Un total de 717 muestras de perros sacrificados fueron evaluadas para determinar la presencia de tumor venéreo transmisible canino, considerando solamente perros mayores de 1 año. La enfermedad fue detectada en 17,48% de las muestras y no hubo diferencia entre el origen, que tuvo un rango de 12,44 a 33,33%. La edad del perro afectó la frecuencia (P<0,05) siendo menor en los perros geriatras (> 7 años; 7,14%), y la más alta en el grupo de 3 a 4 años (20,95). No hubo diferencia entre género (machos 19,13% vs. hembras 15,30%) a pesar de que hubo una tendencia a ser mayor en machos (P=0,07). El tumor venéreo transmisible canino está presente en los perros capturados en las calles de ciudad de México y la presencia de la enfermedad es similar a la reportada en otros países.
A study was conducted at the 9 Rabies Control Centers in the metropolitan zone of Mexico City, from January to July 2007, sampled dogs were captured in the streets. A total of 717 samples were obtained from sacrificed dogs older than 1 year old to determine the presence of canine transmissible venereal tumor. The disease was detected in 17.48% of the samples and there was no difference between origins of sample which ranged from 12.44 to 33.33%. The age of the dog affected (P<0.05) the frequency, being lower in older dogs (>7 years; 7.14%), and the highest in the group from 3 to 4 years (20.95%). There was not difference between sexes (males 19.13% vs. females 15.30%) even when there was a tendency to be higher in males (P=0.07). Canine transmissible venereal tumor was present in street dogs captured in Mexico City and its presence is similar to that reported in other countries.
