Upregulation of BAG3 with apoptotic and autophagic activities in maggot extract­promoted rat skin wound healing.

Maggot extract (ME) accelerates rat skin wound healing, however its effect on cell maintenance in wound tissues remains unclear. B­cell lymphoma (Bcl) 2­associated athanogene (BAG)3 inhibits apoptosis and promotes autophagy by associating with Bcl­2 or Beclin 1. Bcl­2, the downstream effector of signal transducer and activator of transcription 3 signaling, is enhanced in ME­treated wound tissues, which may reinforce the Bcl­2 anti­apoptotic activity and/or cooperate with Beclin 1 to regulate autophagy during wound healing. The present study investigated expression levels of BAG3, Bcl­2, Beclin 1 and light chain (LC)3 levels in rat skin wound tissues in the presence and absence of ME treatment. The results revealed frequent TUNEL­negative cell death in the wound tissues in the early three days following injury, irrespective to ME treatment. TUNEL­positive cells appeared in the wound tissues following 4 days of injury and 150 µg/ml ME efficiently reduced apoptotic rate and enhanced BAG3 and Bcl­2 expression. Elevated Beclin 1 and LC3 levels and an increased LC3 II ratio were revealed in the ME­treated tissues during the wound healing. The results of the present study demonstrate the anti­apoptotic effects of BAG3 and Bcl­2 in ME­promoted wound healing. Beclin 1/LC3 mediated autophagy may be favorable in maintaining cell survival in the damaged tissues and ME­upregulated BAG3 may enhance its activity.