不同海拔地区不同年龄组人外周血白细胞端粒DNA长度变化

The dynamic changing profiles of peripheral white blood cell telomere length in populations of different ages living at different altitude areas

目的探讨不同海拔地区不同年龄组人外周血白细胞端粒DNA长度变化。方法分别选取高原组（花石峡海拔4380m）与平原组（北京海拔43m）健康人外周血标本172份。其中高原组95名（男性47名，女性48名），平原组77名（男性39名，女性38名）。两组年龄分布基本相同。实验采用Southern杂交方法检测其端粒限制性片段长度（terminal restriction fragment，TRF），邻苯三酚氧化法测定超氧化物歧化酶（SOD），硫代巴比妥（TBA）比色法测定丙二醛（MDA）并做统计学分析。结果高原组与平原组健康人平均TRF检测结果，高原组男性TRF值为10．45±1．35，女性为10．50±1．45；平原组男性TRF值为11．29±1．10，女性为11．31±1．13；高原组与平原组男性与女性TRF值均与年龄呈负相关性；对高原组与平原组分别进行男性与女性4个不同年龄段间方差分析，4个年龄段均数问进行比较发现无论男性或女性，高原组与平原组25及55岁组比较，差异有统计学意义。25～44岁和45～65岁高原组和平原组相同年龄段组SOD，MDA测定值相比较，差异有统计学意义。结论高原组人TRF均随年龄增长而逐渐缩短，TRF与年龄间存在负相关关系；高原组与平原组不同性别TRF不同，高原组TRF水平低于平原组；随着年龄的增长高原组TRF缩短更明显。

Objective To investigate the relationship between the length of telomere DNA and age at different altitude areas. Methods All 172 peripheral blood samples were randomly selected from healthy individuals of different ages from 25 to 65 years old. High altitude group （47 males, 48 females） living at an altitude of 4380 m （HA group） ,sea level group （39 males , 38 females） living at an altitude of 43 m （SL group）. The terminal restriction fragment （TRF） length of telomere DNA was measured by Southern blotting analysis. The plasma levels of malonchaldehyde （MDA） and superoxide dismutase （SOD） were assayed. Results Average TRF lengths of males and females in HA groups were 10. 45 ± 1.35 and 10. 50 ± 1.45. Average TRF lengths of males and females in SL groups were 11.29 ± 1.10 and 11.31 ± 1, 13. A negative correlation was shown between the average TRF length and age of males in two groups （P 〈 0. 01 ）. This was also the case for females. ANOVA test was used to analyze the difference between TRF length and gender at different ages （ P 〈 0. 001 ） . It was shown that there was significant difference in TRF length between the male （25 years old and 55 years old） and female （25 years old and 55 years old） in two groups at different ages （ P 〈 0. 05 ）. The plasma levels of SOD and MDA were significant different between HA groups and SL groups （25-44 years old groups /45-65 years old groups） （P 〈 0.05）. Conclusion Obviously shortening of telomere was observed by increasing of ages in high altitude groups. There wasa negative correlation between the length of telomere DNA and ages. Telomere shortening became more obviously in high altitude group than in sea level group in keeping with the age increases.