Chen Xiao-dong, Wu Bo-yu, Jiang Qiong, Wang Shun-bin, Huang Li-ying, Wang Zhong-cheng
Provincial Burns Institute, Union Hospital, Fujian Medical University, Fuzhou 350001, P. R. China.
Zhonghua Shao Shang Za Zhi. 2005 Dec;21(6):430-3.
To investigate the influence of polysaccharide from Aloe Vera (AP) on the proliferation of the human epithelial cells cultured in vitro.
The human epithelial cells undergoing 3 to 4 passages of confluence culture were randomly divided into control and 25, 50, 100, 200 and 400 mg/L AP groups according to different dosage of the polysaccharide (AP) added into the culture medium. In the control group (C), equal volume of DK-SFM medium was added to the culturing cells. The conjugation time of epithelial cells, the changes in the cell morphology and ultrastructure were observed under inverted phase contrast microscope and transmission electron microscope, respectively. The cell proliferation was measured by MTT, cell count analysis and [(3)H]-TdR incorporation. Flow cytometry analysis was employed to detect the cell cycle. The leakage rate of lactate dehydrogenase (LDH) was assayed for the evaluation of the epithelial cell injury.
There was no significant difference in the morphology of the epithelial cells among the groups under inverted phase contrast microscope. But under the transmission electron microscope (TEM), the cells in 100 to 400 mg/L AP groups were seen to have proliferated actively, with euchromatin dominant in the nuclei, while heterochromatin was dominant in the cellular nucleus in control and 25 mg/L AP groups. The confluence time of epithelial cells in 50, 100, 200, 400 mg/L AP groups (154 +/- 12, 141 +/- 20, 130 +/- 19, 124 +/- 13) h preceded noticeably than that in control group (182 +/- 8) h, (P < 0.01). The cell proliferation in 100, 200, 400 mg/L groups reached the peak on the 5th day after AP treatment, while that in control and other groups was delayed by 1 to 2 days. The survival rate of the cells in 25 to 400 mg/L AP groups increased dramatically compared with that in control group, with its [(3)H]-TdR incorporation levels significantly increased in a dose dependent manner. The leakage rate of LDH in 200 and 400 mg/L AP groups was lower than that in control group (P < 0.01). The flow cytometric analysis of the cell cycle distribution revealed that the percentage of cell cycle from phase G0/G1 to G2/M and S in 25 to 400 mg/L AP groups increased significantly in a dose dependent manner compared with that in control group (P < 0.01).
AP might be beneficial to the protection of epithelial cells by promoting cell proliferation through inducing the progression of epidermal cells from phase G0/G1 into G2/M and S phases.
探讨库拉索芦荟多糖（AP）对体外培养的人上皮细胞增殖的影响。
将处于3至4代融合培养的人上皮细胞，根据向培养基中添加的多糖（AP）不同剂量，随机分为对照组以及25、50、100、200和400mg/L AP组。对照组（C）向培养细胞中加入等体积的DK-SFM培养基。分别在倒置相差显微镜和透射电子显微镜下观察上皮细胞的结合时间、细胞形态和超微结构的变化。采用MTT法、细胞计数分析和[³H]-TdR掺入法检测细胞增殖。采用流式细胞术分析检测细胞周期。检测乳酸脱氢酶（LDH）漏出率以评估上皮细胞损伤情况。
倒置相差显微镜下各组上皮细胞形态无明显差异。但在透射电子显微镜（TEM）下，100至400mg/L AP组细胞可见活跃增殖，细胞核中常染色质占优势，而对照组和25mg/L AP组细胞核中异染色质占优势。50、100、200、400mg/L AP组上皮细胞的汇合时间（154±12、141±20、130±19、124±13）h明显早于对照组（182±8）h，（P<0.01）。100、200、400mg/L组细胞增殖在AP处理后第5天达到峰值，而对照组和其他组延迟1至2天。25至400mg/L AP组细胞存活率与对照组相比显著增加，其[³H]-TdR掺入水平呈剂量依赖性显著增加。200和400mg/L AP组的LDH漏出率低于对照组（P<0.01）。细胞周期分布的流式细胞术分析显示，25至400mg/L AP组从G0/G1期到G2/M期和S期的细胞周期百分比与对照组相比呈剂量依赖性显著增加（P<0.01）。
AP可能通过诱导表皮细胞从G0/G1期进入G2/M期和S期来促进细胞增殖，从而对上皮细胞起到保护作用。
