蛆虫分泌物对糖尿病大鼠溃疡组织bFGF和结缔组织生长因子表达的影响及抗茵作用研究

目的 探讨蛆虫分泌物对糖尿病(diabetes mellitus,DM)大鼠溃疡组织bFGF和结缔组织生长因子(connective tissue growth factor,CTGF)表达的影响及预防细菌感染的作用.方法 取3月龄雄性SD大鼠40只,体重300～350 g,制备DM大鼠溃疡创面模型.随机分为2组(n=20),实验组创面涂以丝光绿蝇蛆虫的分泌物,对照组不予处理.术后1～21 d观察创面大体情况,7、14、21 d分别记录两组溃疡面积;术后14 d取两组溃疡组织,制备组织切片,行HE染色观察;3、7、14 d取溃疡表面分泌物行常规细菌培养,检测细菌感染情况;术后7、14、21 d用免疫组织化学法处理切片,显微镜下对bFGF、CTGF阳性表达细胞进行计数分析.结果 实验组创面清洁,新鲜肉芽生长,无脓性分泌物,愈合情况良好,无金色葡萄球菌感染;对照组创面渗出、糜烂严重,创面不断加大加深,愈合情况不良,金色葡萄球菌感染率为60%.术后7、14、21 d实验组溃疡面积分别为(1.83±0.23)、(0.39±0.08)cm2和0,对照组分别为(2.18±0.67)、(3.57±0.53)、(3.94±0.67)cm2;两组比较差异均有统计学意义(P＜0.05).14 d组织学观察示实验组上皮组织新生,创缘炎性坏死物减少,纤维瘢痕形成;对照组大量炎性细胞浸润,坏死组织较多.术后7、14 d,实验组bFGF阳性表达数分别为23.76±3.34、52.76±4.84,对照组为18.88±2.16、46.04±4.00;实验组CTGF阳性表达数分别为18.76±3.24、46.52±4.07,对照组为12.52±3.03、40.52±3.96;两组比较差异均有统计学意义(P＜0.05)21 d,两组bFGF及CTGF阳性表达数差异无统计学意义(P＞0.05).结论 蛆虫分泌物能提高DM溃疡组织bFGF、CTGF的表达,有效促进创面愈合,预防组织细菌感染.

INFLUENCE OF MAGGOT SECRETION ON EXPRESSION OF bFGF AND CONNECTIVE TISSUE GROWTH FACTOR IN ULCER TISSUE OF DIABETES MELLITUS RAT AND ANTIBACTERIUM STUDY

OBJECTIVE: To study the influence of maggot secretion on expression of bFGF and connective tissue growth factor (CTGF) in ulcer tissue of diabetes mellitus (DM) rats and its antibacterial function. METHODS: There were 40 3-month-old SD male rats (weighing 300-350 g) which were randomly divided into 2 groups: control group and experimental maggot secretion group. The model of ulcer wound of DM rats was made. The ulcer wound of DM rats in maggot secretion group spread maggot secretions, but no secretion on ulcer wound was found in control group. The morphological and tissue changes of ulcer wound were observed at different times, and the conditions of bacterial infection on ulcer wound in the two groups were checked. Tissue slices were prepared on 7, 14 and 21 days, respectively; immunohistological detection of bFGF and CTFG in ulcer wound of the two groups was done; and the cell number of positive expression of bFGF and CTFG was counted. RESULTS: It was found that the healing of ulcer was dominant in experimental group; the wound was clean; the tissue regenerated and no Staphylococcus aureus infection was seen. Bad healing was obtained in control group; tissue necrosis was found and the rate of Staphylococcus aureus infection was 60%. Positive expression cell number of bFGF in ulcer wound was detected on 7 and 14 days after operation with 23.76 +/- 3.34 and 52.76 +/- 4.84 in experimental group, and 18.88 +/- 2.16 and 46.04 +/- 4.00 in control group. Positive expression cell number of CTGF in ulcer wound was detected on 7 and 14 days after operation with 18.76 +/- 3.24 and 46.52 +/- 4.07 in experimental group, and 12.52 +/- 3.03 and 40.52 +/- 3.96 in control group. There was significant difference between positive expressions of bFGF and CTFG in the two groups (P < 0.05). CONCLUSION: The maggot secretion can elevate the expressions of bFGF and CTFG in ulcers, promote healing and prevent bacterial infection.