Effects of astrocyte conditioned medium on neuronal AChE expression upon 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin exposure. (25th August 2019)

• Record Type: Journal Article
• Authors: Sha, Rui; Chen, Yangsheng; Luo, Yali; Liu, Yiyun; Xu, Li; Xie, Heidi Qunhui; Zhao, Bin
• Is Part Of: Chemico-biological interactions. Volume 309(2019)
• Publication Date: 2019-08-25
• Subjects: Dioxin -- Astrocyte -- Neuron -- Astrocyte conditioned medium -- Acetylcholinesterase; AChE acetylcholinesterase -- TCDD 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin -- ACM astrocyte-derived conditioned medium -- AChET AChE T subunit -- PRiMA proline-rich membrane anchor -- AhR aryl hydrocarbon receptor -- AD Alzheimer's disease -- CNS central nervous system -- CSPGs chondroitin sulfate proteoglycans -- VRL Vital River Laboratories -- HBSS Hank's Balanced Salt Solution -- MEM Minimum Essential Medium -- GFAP glial fibrillary acidic protein -- DMEM Dulbecco's modified Eagle's medium -- Ara-c cytosine arabinoside -- DMSO dimethyl sulfoxide -- OD optical density -- NM normal medium -- NGF nerve growth factor -- NHANES National Health and Nutrition Examination Survey; Biochemistry -- Periodicals; Toxicological chemistry -- Periodicals; Biochemistry -- Periodicals; Biologie moléculaire -- Périodiques; Biochimie -- Périodiques; Toxicologie biochimique -- Périodiques; 572
• DOI: 10.1016/j.cbi.2019.05.052
• Languages: English
• ISSNs: 0009-2797

Abstract

Abstract: Acetylcholinesterase (EC3.1.1.7; AChE) is a key enzyme in the cholinergic system. Emerging evidence has shown that 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD), a typical persistent organic pollutant, suppressed neuronal AChE activity via dysregulation of different biosynthesis processes in human and rat neuronal cells. In the nervous system, astrocytes protect neurons from environmental pollutants. As a known target cell of TCDD, the astrocyte might be involved in TCDD effects on neuronal AChE. Therefore, in the present study, we found astrocyte-derived conditioned medium (ACM) could induce AChE activity preferentially in mature neurons in the absence of TCDD. The enzymatic activity of AChE was generally decreased in cultured cortical neurons upon direct treatment with TCDD (0.003–0.01 nM). This trend of changes in AChE activity was not significantly altered in immature neurons exposed to ACM produced in the presence of TCDD (TACM group), but reversed in mature neurons. Compared with effects of treatment with ACM plus TCDD (ACMT), a significant differential effect on AChE activity was found in the TACM group in response to TCDD treatment specifically in immature neurons, suggesting the presence of a TCDD-specific active component derived from the astrocyte. Inconsistent alterations in expression and enzymatic activities of the AChE T subunit (AChET ) and the proline-rich membrane anchor (PRiMA) were found, suggesting that a mechanism of action beyond the transcriptional level might be involved. These data indicate that the astrocyte might play a protective role in TCDD-induced alterations of neuronal AChE in certain stages of differentiation. Highlights: Astrocyte conditioned medium has promoting effect on the AChE activity in matured neurons. Astrocyte-derived factor(s) protect AChE activity against TCDD treatment. The above effect on AChE activity is inconsistent with that of AChET and PRiMA mRNA.