超高剂量率与常规剂量率脉冲电子线对秀丽隐杆线虫的影响

Effects of pulsed electron beams with ultra-high dose rate and conventional dose rate on Caenorhabditis elegans

目的利用模式生物-秀丽隐杆线虫研究超高剂量率脉冲电子线对机体的影响。方法将成年期野生型株系(N2)线虫同步化后培养至L4期,随机分为对照组(SHAM组)、常规剂量率组(CONV组)和超高剂量率组(UHDR组)。CONV组和UHDR组辐射剂量均为3 Gy(脉冲电子线照射,剂量率分别为0.3和200 Gy/s)。辐照结束后,计数每组产卵量;照后3、6和10 d时,分别检测线虫发育、运动能力和存活时间。结果照后第3天时,CONV组和UHDR组线虫体长均明显短于SHAM组(t=4.81、4.83,P<0.05),体宽差异无统计学意义(P>0.05)。第6和10天时,与SHAM组相比,CONV组体长和体宽均明显减小(t=3.18~3.63,P<0.05);而UHDR组体长明显增加(t=-9.85、-2.87,P<0.05),体宽差异无统计学意义(P>0.05)。与CONV组比较,第6和10天时,UHDR组体宽明显增加(t=-4.43、-3.37,P<0.05)。与SHAM组相比,照后第6天,CONV组和UHDR组头部摆动、身体弯曲次数均明显下降(t=2.91、3.52、3.97、2.71,P<0.05);第10天,3组运动能力均较弱且差异均无统计学意义(P>0.05)。与SHAM组相比,CONV组和UHDR组产卵量均显著降低(t=1.72、5.54,P<0.05),但UHDR组线虫产卵量显著高于CONV组(t=-5.99,P<0.05)。与SHAM组相比,CONV组线虫寿命明显缩短(χ^(2)=8.49,P<0.05),而UHDR组线虫存活时间差异无统计学意义(P>0.05)。结论CONV电子射线可导致秀丽线虫发育受损、运动能力降低、产卵量减少和寿命缩短,但在相同剂量下UHDR脉冲电子射线引起的损伤程度较轻。

ObjectiveTo explore the effects of ultra-high dose rate pulsed electron beams on Caenorhabditis elegans(C.elegans).MethodsThe adult wild-type strain(N2)of C.elegans was synchronized and cultured to L4 stage,and then randomly divided into control group(SHAM group),conventional radiotherapy dose rate group(CONV group)and ultra-high dose rate radiation group(UHDR group).The CONV and UHDR groups were exposed to 3 Gy of the pulsed electron beam at dose rates of 0.3 and 200 Gy/s,respectively.After irradiation,the egg-laying capacity of each group was assessed,and the developmental progress,motility,and survival rates each were evaluated at day 3,6,and 10.ResultsOn the 3 rd day post-irradiation,both the CONV and UHDR groups showed shorter body lengths compared to the SHAM group(t=4.81,4.83,P<0.05),with no significant differences in body width(P>0.05).On the 6 th and 10 th days,the CONV group showed a significant reduction in both body length and width compared to the SHAM group(t=3.18-3.63,P<0.05),whereas the UHDR group displayed a significant increase in body length(t=-9.85,-2.87,P<0.05)with no significant change in body width.When comparing the UHDR group to the CONV group on day 6 and 10,a significant increase in body width was observed(t=-4.43,-3.37,P<0.05).Motor activity,including head swinging and body bending,significantly decreased in the CONV and UHDR groups compared to the SHAM group on day 6(t=2.91,3.52,3.97,2.71,P<0.05),with no significant differences among the three groups by day 10(P>0.05).Egg-laying capacity significantly reduced in both irradiated groups compared to the SHAM group(t=1.72,5.54,P<0.05),while the UHDR group exhibited higher fecundity than the CONV group(t=-5.99,P<0.05).Lifespan was significantly shortened in the CONV group compared to the SHAM group(χ^(2)=8.49,P<0.05),whereas the survival time of the UHDR group was not significantly differ from that of the SHAM group(P>0.05).ConclusionsExposure to a conventional electron beam result in developmental delays,reduced mobility,decreased fecundity,and a shortened lifespan in C.elegans.However,only slight side effects were observed when C.elegans were exposed to an ultra-high dose rate pulsed electron beam at the same dosage.