Maternal Nicotine Exposure During Gestation and Lactation Period Affects Behavior and Hippocampal Neurogenesis in Mouse Offspring
FRONTIERS IN PHARMACOLOGY
Authors: Liu, Fei; Tao, Xinrong; Pang, Gang; Wu, Diqing; Hu, Yuting; Xue, Song; Liu, Jing; Li, Bing; Zhou, Li; Liu, Qiang; Zhang, Yong-Mei
Abstract
Cigarette smoking or nicotine exposure during pregnancy is associated with numerous obstetrical, fetal, and developmental complications, as well as an increased risk of adverse health consequences in the adult offspring. In this study, we examined the effects of maternal nicotine exposure during perinatal and lactation stages on behavioral performance and hippocampal neurogenesis in the adolescent stage of offspring mice. Female C57BL/mice received nicotine in drinking water (200 mu g/ml nicotine) or vehicle (1% saccharin) starting from 2 weeks premating until the offspring were weaned on postnatal day 20. Experiments started on postnatal day 35. Female offspring with maternal nicotine exposure presented an increase in anxiety-like behavior in an open-field test. BrdU assay revealed that nicotine offspring presented an increase in cell proliferation in hippocampal dentate gyrus, but the number of BrdU(+) cells was decreased in one week and further decreased in three weeks. The occurrence of disarray of DCX+ cells increased in both male and female nicotine offspring. The density of microglial marker protein Iba1 was significantly increased in the nicotine offspring. Furthermore, the expression of microglia marker Iba1, the CX3CL1, CX3CR1, and downstream molecules PKA and p-ErK were significantly increased in the nicotine group. In summary, maternal nicotine exposure affects both hippocampal neurogenesis and microglial activity in the adolescent offspring.
In vivo direct reprogramming of glial linage to mature neurons after cerebral ischemia
SCIENTIFIC REPORTS
Authors: Yamashita, Toru; Shang, Jingwei; Nakano, Yumiko; Morihara, Ryuta; Sato, Kota; Takemoto, Mami; Hishikawa, Nozomi; Ohta, Yasuyuki; Abe, Koji
Abstract
The therapeutic effect of in vivo direct reprogramming on ischemic stroke has not been evaluated. In the present study, a retroviral solution (1.5-2.0 x 10(7) /ul) of mock pMX-GFP (n = 13) or pMX-Ascl1/Sox2/NeuroD1 (ASN) (n = 14) was directly injected into the ipsilateral striatum and cortex 3 days after 30 min of transient cerebral ischemia. The reprogrammed cells first expressed neuronal progenitor marker Dcx 7 and 21 days after viral injection, then expressed mature neuronal marker NeuN. This was accompanied by morphological changes, including long processes and synapse-like structures, 49 days after viral injection. Meanwhile, therapeutic improvement was not detected both in clinical scores or infarct volume. The present study provides a future novel self-repair strategy for ischemic stroke with beneficial modifications of the inducer-suppressor balance.