Fig 1.
Comparison of the quality of maggot extracts prepared from the baked maggots and fresh maggots by SDS-PAGE electrophoresis.
Fig 2.
Establishment of diabetic rat model via streptozotocin injection.
A, The appearance and blood glucose measurement of normal rats and streptozotocin-treated rats. B, The average fasting blood glucose levels (BGL) of SD rats in the 5 groups. C, The average body weights of SD rats in the experimental groups at different time points. The data are presented as mean ± SD. n = 10. *, P< 0.01, compared with normal rats.
Table 1.
Average fasting blood glucose levels and body weights of the rats in different groups during the treatments.
Fig 3.
The effects of different treatments on wound healing at different time points.
A, A round skin wound was made on rat dorsa. B, The wound model rats were divided into 5 experimental groups and their wounds were locally treated by Vaseline, rhEGF gel (rhEGF) and maggot extract (M.E.), respectively. The wounds of normal rats (N) and the diabetic rats (N/D) without treatment were cited as blank controls. C, The wound healing rates of five experimental groups. D, Analogic diagram reflecting the progress of wound healing. The data are shown as mean ± SD, n = 10. *, P < 0.05.
Table 2.
Average wound healing rates of five experimental groups at three time points.
Fig 4.
The morphology analysis of wound healing in different experimental groups on the 14th day of the experiment.
A, Composite images of hematoxilyn/eosin-stained central wound sections of five experimental groups to show re-epithelialization (×50). Epithelial tongues are highlighted by dash line. Insets: the regions in higher magnification (×200). B, Masson’s trichrome staining for evaluating granulation tissue (gt) composition (×50). Red color: cytoplasm, muscle fibers; blue color: collagen fibers. Insets: the regions in higher magnification (×200). C and D, Quantitative analysis of re-epithelialization (percentage of distance covered by epidermis) and granulation tissue (percentage of collagen fibers in granulation tissue). *, P < 0.01; #, P > 0.05.
Fig 5.
Distinct STAT3 activation and its downstream gene expression patterns between normal and diabetic rat wound tissues.
Immunohistochemical staining (A) and immunofluorescent labeling (B) were performed on the wound tissues. Western blotting (C) was conducted on the sample proteins prepared from the wound tissues of normal (N) and diabetic rats without any treatments (N/D). The data are shown as mean ± SD. n = 10. *, P < 0.05.
Fig 6.
Enhanced STAT3 activation and upregulated VEGF, Cyclin D1 and Bcl-2 in maggot extract and rhEGF treated wound tissues.
Immunohistochemical stainings (A), Western blottings (B) and immunofluorescent labelings (C) were performed on the samples of the vaseline, maggot extract (M.E.) and rhEGF treated wounds of the diabetic rats. The data are shown as mean ± SD. n = 10. *, P < 0.05.