Individual analysis of age-associated changes in reproductive activity and lifespan of Drosophila virilis

In the TK strain of Drosophila virilis, age-associated changes in reproductive activities (copulating activity and fertility in males and egg-laying activity in females) and lifespan were examined in individual flies. The mean lifespan of individually aged flies was about 11 weeks for both males and females. Copulating activity was maximum in two-week old males, then decreased gradually and finally ended at the age of 13 weeks at which about half of males were still surviving. Females also had a peak in egg-laying activity at the age of two weeks while no eggs were laid by females older than ten weeks, although more than half of females were alive at the stage. Analyses of the relationship between reproductive activity and lifespan of individual flies revealed that shorter lived males exhibited a higher copulating activity in the early stage of their lives than longer lived males. In males whose lifespan was less than ten weeks the reproductive period increased with the lifespan while the post-reproductive period was almost constant (one to two weeks). In males living longer than ten weeks, the reproductive period remained constant (about eight weeks) while the post-reproductive period increased in parallel with the total lifespan. Similar tendencies were also observed in the egg-laying activity of female flies.     

麻花秦艽-红景天药对不同比例配伍抗缺氧作用及机制研究

目的 筛选麻花秦艽-红景天药对抗缺氧的最佳配伍比例，联合体内、外实验及网络药理学探讨其抗缺氧作用及可能机制。方法 将PC12细胞进行分组，通过Na₂S₂O₄法、H₂O₂法及物理缺氧法建立细胞缺氧模型，对麻花秦艽-红景天药对抗缺氧配伍比例进行初步筛选；将80只SPF级雄性昆明小鼠随机分为空白组、模型组、阳性组、麻花秦艽-红景天不同配伍比例组（2：8，3：7，4：6，5：5，6：4，7：3，8：2），每组8只。预先灌胃给药15 d后，除空白组外，其余各组均进行常压缺氧试验，记录各组小鼠生存时间并检测空白组、模型组、阳性组、麻花秦艽-红景天4：6组及麻花秦艽-红景天3：7组小鼠肺组织中的炎性细胞因子、MDA含量及SOD活力；通过网络药理学、分子对接技术对麻花秦艽-红景天药对抗缺氧机制进行初步探讨，并通过qPCR进行实验验证。结果 体外实验研究发现，麻花秦艽-红景天药对具有较好的抗缺氧活性；体内实验结果显示，4：6及3：7配伍比例麻花秦艽-红景天药对可明显提高小鼠的存活时间，降低肺组织中NF-κB、IL-6及IL-1β及MDA含量，升高IL-10含量及SOD活力，且以麻花秦艽-红景天3：7组疗效最佳；网络药理学研究发现，麻花秦艽-红景天药对抗缺氧的潜在活性成分可能为熊果酸、齐墩果酸、没食子乙酸乙酯等，核心靶点有SRC、PIK3CA、MAPK3等，其抗缺氧作用信号通路主要为PI3K-Akt、HIF-1等。qPCR结果显示，麻花秦艽-红景天可升高缺氧小鼠肺组织中的PI3K、Akt、mTOR及p62表达。分子对接验证显示核心靶点SRC、PIK3CA及p62与潜在活性成分齐墩果酸、山奈酚、没食子乙酸乙酯、槲皮素的结合活性较好。结论 麻花秦艽-红景天药对具有抗缺氧活性，其通过抗炎、抗氧化应激及调控自噬发挥抗缺氧作用，可能与PI3K/Akt信号通路有关。