女性為何普遍比男性更長(zhǎng)壽？一項(xiàng)最新研究成果顯示,，女性的免疫系統(tǒng)衰老速度較慢,，這可能是令女性壽命更長(zhǎng)的一大優(yōu)勢(shì),。
日本研究人員5月15日在英國(guó)《免疫與衰老》雜志上報(bào)告說(shuō),，他們追蹤了356名20歲至90歲健康男女的血液情況,，特別是隨著年齡增長(zhǎng)，這些人血液中與免疫有關(guān)的白細(xì)胞和細(xì)胞因子水平的變化情況,。
結(jié)果發(fā)現(xiàn)，雖然在衰老過(guò)程中白細(xì)胞總數(shù)都會(huì)下降,，但男性白細(xì)胞中的Ｔ細(xì)胞和Ｂ細(xì)胞等淋巴細(xì)胞減少速度明顯快于女性,，而這兩種細(xì)胞均與抵抗細(xì)菌感染有關(guān)。女性在衰老過(guò)程中,，與免疫有關(guān)的細(xì)胞因子等其他幾項(xiàng)免疫參數(shù)的表現(xiàn)也優(yōu)于男性,。
領(lǐng)導(dǎo)這項(xiàng)研究的日本東京醫(yī)科齒科大學(xué)教授廣川勝郁說(shuō)，雌性激素有助于淋巴細(xì)胞的產(chǎn)生和調(diào)控,，從而影響到免疫力,，這可能是女性免疫系統(tǒng)衰老速度比男性更慢的原因之一。
研究人員說(shuō),，女性比男性更長(zhǎng)壽是普遍現(xiàn)象,，曾有研究從線粒體基因差異等方面作出解釋，而此次研究是首次從免疫系統(tǒng)角度解釋這一現(xiàn)象,。據(jù)介紹,，日本女性比男性平均壽命要長(zhǎng)將近6歲,，英國(guó)兩性間的平均壽命差為3歲。（生物谷Bioon.com）
生物谷推薦英文摘要：
Immunity & Ageing doi:10.1186/1742-4933-10-19
Slower immune system ageing in women versus men in the Japanese population
Katsuiku Hirokawa, Masanori Utsuyama, Yoshio Hayashi, Masanobu Kitagawa, Takashi Makinodan and Tamas Fulop
Background Gender-related differences in humans are commonly observed in behaviour, physical activity, disease, and lifespan. However, the notion that age-related changes in the immune system differ between men and women remains controversial. To elucidate the relationship between immunological changes and lifespan, peripheral blood mononuclear cells from healthy Japanese subjects (age range: 20--90 years; N = 356) were analysed by using three-colour flow cytometry. The proliferative activities and cytokine-producing capacities of T cells in response to anti-CD3 monoclonal antibody stimulation were also assessed. Results An age-related decline in the number of T cells, certain subpopulations of T cells (including CD8+ T cells, CD4+CDRA+ T cells, and CD8+CD28+ T cells), and B cells, and in the proliferative capacity of T cells was noted. The rate of decline in these immunological parameters, except for the number of CD8+ T cells, was greater in men than in women (p < 0.05). We observed an age-related increase or increasing trend in the number of CD4+ T cells, CD4+CDRO+ T cells, and natural killer (CD56+CD16+) cells, as well as in the CD4+ T cell/CD8+ T cell ratio. The rate of increase of these immunological parameters was greater in women than in men (p < 0.05). T cell proliferation index (TCPI) was calculated from the T cell proliferative activity and the number of T cells; it showed an age-related decline that was greater in men than in women (p < 0.05). T cell immune score, which was calculated using 5 T cell parameters, also showed an age-related decline that was greater in men than in women (p < 0.05). Moreover, a trend of age-related decreases was observed in IFNgamma, IL-2, IL-6, and IL-10 production, when lymphocytes were cultured with anti-CD3 monoclonal antibody stimulation. The rate of decline in IL-6 and IL-10 production was greater in men than in women (p < 0.05). Conclusion Age-related changes in various immunological parameters differ between men and women. Our findings indicate that the slower rate of decline in these immunological parameters in women than that in men is consistent with the fact that women live longer than do men.
