Georgetti Sandra R, Casagrande Rúbia, Verri Waldiceu A, Lopez Renata F V, Fonseca Maria J V
Department of Pharmaceutical Science, Faculty of Pharmaceutical Sciences of Ribeirao Preto - USP, Avenue Do Café s/n, CEP 14040-903, Ribeirao Preto, SP, Brazil.
Int J Pharm. 2008 Mar 20;352(1-2):189-96. doi: 10.1016/j.ijpharm.2007.10.037. Epub 2007 Nov 4.
In the present study it was evaluated the: (i) functional stability of the soybean extract as a raw material and dispersed in two different topical formulations, (ii) skin retention using modified Franz diffusion cells, and (iii) in vivo activity of these formulations to inhibit 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced hydrogen peroxide (H(2)O(2)) and malondialdehyde (MDA) increases in the skin of hairless mice. The physico-chemical stability was evaluated by pH, globule size and centrifugation test. Furthermore, functional stability was also evaluated by antilipoperoxidative activity. The two topical formulations were stored at 4 degrees C, 30 degrees C/60% RH and 40 degrees C/70% RH for 6 months. The evaluation of the antiperoxidative stability of soybean extract itself and incorporated in formulations did not demonstrate loss of activity by storage at 4 degrees C/6 months. During 6 months of the study in different storage conditions the formulations 1 and 2 added or not with soybean extract were stable to physico-chemical tests. The effect of antioxidant compounds detected by the inhibition of MDA formation was time-dependent for formulation 2 as detected in the skin retention study. Pretreatment with formulation 1 or 2 significantly diminished TPA-induced H(2)O(2) and MDA generation. In conclusion, the present results suggest for the first time that formulations containing soybean extract may be a topical source of antioxidant compounds that decrease oxidative damages of the skin.
在本研究中，评估了：(i) 大豆提取物作为原料并分散于两种不同外用制剂中的功能稳定性；(ii) 使用改良的Franz扩散池评估皮肤滞留情况；(iii) 这些制剂在体内抑制12 - O - 十四烷酰佛波醇 - 13 - 乙酸酯（TPA）诱导的无毛小鼠皮肤中过氧化氢（H₂O₂）和丙二醛（MDA）增加的活性。通过pH值、小球大小和离心试验评估物理化学稳定性。此外，还通过抗脂质过氧化活性评估功能稳定性。将两种外用制剂分别在4℃、30℃/60%相对湿度和40℃/70%相对湿度下储存6个月。对大豆提取物本身及其在制剂中的抗过氧化稳定性评估表明，在4℃储存6个月未出现活性丧失。在不同储存条件下进行的6个月研究期间，添加或未添加大豆提取物的制剂1和制剂2在物理化学测试中均稳定。如在皮肤滞留研究中所检测到的，制剂2中通过抑制MDA形成检测到的抗氧化化合物的作用具有时间依赖性。用制剂1或制剂2预处理可显著减少TPA诱导的H₂O₂和MDA生成。总之，目前的结果首次表明，含有大豆提取物的制剂可能是一种外用抗氧化化合物来源，可减少皮肤的氧化损伤。
