[Screening genes of differential expression in BALB/C mice thymus: a pilot study of effect of salmon milt DNA (SMD) on age-related involutions].
OBJECTIVE
To investigate the effect and its mechanism of salmon milt DNA (SMD) on age-related involutions in mouse thymus.


METHODS
Female BALB/C mice aged 10 months were divided randomly into three groups according to their weights. They were high dosage group (333.33 mg.kg(-1).b.w.d(-1)), low dosage group (166.67 mg.kg(-1).b.w.d(-1)) and control group (0 mg.kg(-1).b.w.d(-1)). After five weeks, their thymus indexes were measured and the thymocytes were counted and the thymus cortex thicknesses were also measured using Image-Pro Plus (version. 4.0) software in the thymus section. All the data were analyzed by SAS statistic software. Microarray technique was applied to screen the gene fragments, which were differentially expressed between the high dosage group and the control group, together with RT-PCR to further confirm some of them.


RESULTS
No significant differences of the variables including body weight, thymus weight and thymus indexes among the three groups were found. The thymocytes quantities of thymus cortex and medulla in the high dosage group were significantly higher than those of the control group (P < 0.01 and P < 0.05, respectively). The thymus cortex thicknesses of both SMD supplement groups were significantly higher than that of the control group (P < 0.01 and P < 0.05 respectively). 112 differently expressed gene fragments were isolated. Furthermore, we found the fragments with the logged number of U23789, X80232 and Aw209102 were highly expressed in the high dosage group when RT-PCR technique was used.


CONCLUSIONS
SMD may reverse the age-related involutions in mouse thymus via up-regulation the expression of proliferation related genes and via up-regulation the expression of development and differentiation related genes simultaneously.
Cheng
Min
M
Department of Health Chemistry and Microbiology, Public Health College, Harbin Medical University, Harbin, 150001, China.
Du
Bo-yu
BY
Chu
Wen-feng
WF
Chen
Wen-hua
WH
Yu
Ping
P
Li
Rong
R
D000199:Actins / Q000235:genetics; D000375:Aging / Q000187:drug effects* / Q000235:genetics; D000818:Animals; D002455:Cell Division / Q000187:drug effects / Q000235:genetics; D004247:DNA / Q000008:administration & dosage*; D005260:Female; D015870:Gene Expression / Q000187:drug effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D010865:Pilot Projects; D011897:Random Allocation; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012474:Salmon / Q000235:genetics*; D013950:Thymus Gland / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism
D000199:Actins; D004247:DNA