| 摘要: | 為研究母乳中的上皮生長因子(epidermal growth factor，EGF)對人類腸道生長
發育的影響，先收集的20件台北地區產後8--20天母乳樣本，以酵素免疫分析法
(enzyme linked immunosorbent assay，ELISA)定量其EGF平均濃度約為7.5 nM，再以
人類結腸腺癌細胞Caco-2為模型，分別添加5%人奶及相當於5%人奶生理濃度EGF
(0.375 nM，0.05x EGF)、人奶生理濃度EGF(7.5 nM，1x EGF)以及控制組4組，培養
0、1、3、12、24、36、48小時，觀察人奶及EGF對Caco-2細胞生長的影響，及其生長
調節作用與c-Jun表現之關係。
結果發現：細胞總數方面，與0小時控制組比較，5%人奶組培養24及36小時細胞數
顯著增加；1x EGF組培養12小時細胞數即開始明顯增加，36小時幾乎可倍增。12小時
培養後，5%人奶、0.05x及1x EGF組細胞RNA含量分別比控制組增加62%、20%、40%，
細胞DNA含量分別比控制組增加21%、18%、30%，細胞蛋白質含量分別比控制組增加32%
、35%、67%。促進c-Jun表現方面，5%人奶組於12小時最強（為0小時控制組6.9倍），
0.05x及1x EGF組於12小時後漸增、36小時最強（分別為0小時控制組6.9及5.4倍）。
故人奶與EGF均可能經由增加c-Jun表現之路徑，促進腸細胞之生長，且EGF與人奶
的效果相近，推論人奶中主要影響腸細胞生長的因子為EGF，未來值得再研究EGF應用
於腸道發育尚未完整的早產兒或低體重初生兒。
To investigate the effects of epidermal growth factor (EGF) in human
milk on growth and development of human intestine, the mean concentration
of EGF (7.5 nM) in twenty collected human milk samples from 8-20 days
postpartum in Taipei was determined by enzyme linked immunosorbent assay
(ELISA). Furthermore, the effects of human milk or EGF on growth of human
intestinal cells, and the relation between growth regulation and c-Jun
expression were studied after the addition of 5% human milk, 0.375 nM EGF
(relevant to EGF concentration in 5% human milk, 0.05x EGF), or 7.5 nM EGF
(relevant to EGF concentration in human milk, 1x EGF) for 1, 3, 12, 24, 36,
and 48 h.
The results showed that the cell numbers were significantly increased
after 24 and 36 h in the 5% human milk group as compared to the control
group at 0 h. Whereas the 1x EGF group had significantly greater cell
numbers after 12 h, and almost had twice cell numbers after 36 h. After
12 h incubation, cellular RNA content was increased by 62, 20, and 40% in
the 5% human milk, 0.05x EGF, and 1x EGF groups, respectively. Cellular
DNA content was elevated by 21, 18, and 30% in the 5% human milk, 0.05x EGF,
and 1x EGF groups, respectively. Cellular protein content was raised by 32,
35, and 67% in the 5% human milk, 0.05x EGF, and 1x EGF groups,
respectively, as compared to the control group. The 5% human milk group had
the greatest c-Jun expression (6.9 times of the control group at 0 h) after
12 h, whereas, the 0.05x and 1x EGF groups tended to increase c-Jun
expression after 12 h and reached to the greatest (6.9 and 5.4 times of the
control group at 0 h, respectively) after 36 h.
In conclusion, both human milk and EGF may enhance the growth of
intestinal cells through an increase in c-Jun expression, and the
effectiveness was similar between human milk and EGF. Therefore, the factor
affecting intestinal growth was mainly contributed by EGF. In the future,
the application of EGF to the immature development of intestine in preterm
or low-birth-weight infants is required further studies. |
