RESUMEN
High-mobility group box 1 (HMGB1) protein is the major component of the nonhistone nuclear protein group and is involved in nucleosome stabilization and transcription regulation. HMGB1 has recently been focused on as a proinflammatory cytokine associated with various inflammatory diseases and as a target of anti-inflammatory therapy. Mastitis, a serious inflammatory disease of dairy cows, is caused by infection of the mammary gland and has detrimental effects on the quantity and quality of milk. By detecting the presence of HMGB1 in milk, we investigated the correlation between HMGB1 concentration and the severity of bovine mastitis, which was determined using the California Mastitis Test and somatic cell count (SCC). We detected a substantial amount of HMGB1 in mastitic milk but not in the milk from normal cows. We used the Spearman rank correlation coefficient to assess the relationship between HMGB1 concentration and SCC and found a significant correlation (n = 12, r = 0.975). Thus, we confirmed the positive correlation between HMGB1 concentration and SCC in milk, i.e., the severity of mastitis, which suggested that HMGB1 in milk is a new indicator of bovine mastitis.
Asunto(s)
Proteína HMGB1/metabolismo , Mastitis Bovina/metabolismo , Leche/metabolismo , Animales , Western Blotting/veterinaria , Bovinos , Recuento de Células/veterinaria , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Mastitis Bovina/diagnóstico , Mastitis Bovina/microbiología , Leche/microbiología , Estadísticas no ParamétricasRESUMEN
DNA fragmentation is a biochemical hallmark of apoptosis. Several endonucleases, including CAD/DFF40 and endonuclease G, are implicated in DNA fragmentation. DNase gamma has also been considered to be one of the enzymes involved, but its role in relation to CAD/DFF40 in apoptosis has not been fully elucidated. Here, we distinguished between DNase gamma-dependent and CAD/DFF40-dependent DNA fragmentations. We found that DNase gamma activities appeared in the late apoptotic phase and accelerated DNA fragmentation. Thus, even if the apoptotic DNA fragmentation is initiated by CAD/DFF40, DNase gamma is required for the more complete digestion of the genomic DNA in dying cells.