CEHS Summer Undergraduate Research Program: University of Montana

丙烯醛(CH2=CHCHO)是一种高活性、易挥发的化学物质，可能意外或故意释放， 导致眼睛、皮肤和呼吸毒性。基于丙烯醛的化学，已知以生物为靶标 DNA中包括鸟氨酸在内的亲核试剂，以及关键成分中的半胱氨酸、赖氨酸、组氨酸和精氨酸残基 转录因子、蛋白酶和其他蛋白质的区域。因此，拥有如此广泛的潜力 生物靶点很难确定体内最敏感的靶点，以此为可能的基础 治疗性干预。据报道，丙烯醛是钙离子通透性瞬时受体的激动剂。 潜在阳离子通道，A亚家族，成员1(TRPA1)。因此，丙烯醛在肺上靶向TRPA1 巨噬细胞有望增加炎性细胞因子的产生。然而，研究报告称， 丙烯醛抑制巨噬细胞细胞因子的产生。预计丙烯醛将针对以下硫醇基团 蛋白酪氨酸磷酸酶(PTP)活性的共同临界点使它们成为一个重要而合乎逻辑的 可解释巨噬细胞细胞因子产生抑制的靶蛋白家族。在各种PTP中， 据报道，PTP1B被丙烯醛不可逆转地抑制，但没有报道表明PTP1B是靶标 丙烯醛在体内的毒性。由于PTP1B是一种关键的调节PTP，参与关键途径和疾病以及 作为丙烯醛暴露的目标，可以解释许多已报道的丙烯醛暴露的结果，特别是 在亚致死浓度下。由于丙烯醛毒性的确切机制仍不确定，该项目将 填补了重要的知识空白，在体外定义并首次论证了体内是否存在抑制作用 PTP1B催化活性有助于确定丙烯醛亚致死性呼吸毒性的机制 浓度。目标1中的研究将证明丙烯醛阻断巨噬细胞中PTP1B的活性和 并将其与丙烯醛对TRPA1的影响进行比较。AIM 2中的研究将证明 丙烯醛在体内亚致死剂量暴露可阻断肺巨噬细胞PTP1B活性降低 巨噬细胞释放炎性细胞因子。这些研究将提供新的机理信息 在体外和体内的丙烯醛毒性，将有助于解释已报道的丙烯醛暴露的不良影响和 为制定医学对策以减轻丙烯醛暴露的不良影响提供指导。

Acrolein (CH2=CHCHO) is a highly-reactive, volatile chemical that may be released accidentally or intentionally, resulting in eye, skin, and respiratory toxicity. Based on acrolein’s chemistry, it is known to target biological nucleophiles including guanine in DNA, as well as cysteine, lysine, histidine and arginine residues in critical regions of transcription factors, proteases and other proteins. Consequently, with such a broad range of potential biological targets it has been difficult to be certain of the most sensitive targets in vivo on which to base possible therapeutic interventions. Acrolein has been reported to be an agonist for the Ca2+-permeable transient receptor potential cation channel, subfamily A, member 1 (TRPA1). Therefore, acrolein targeting TRPA1 on lung macrophages would be expected to increase inflammatory cytokine production. However, studies have reported that acrolein inhibits macrophage cytokine production. Acrolein is expected to target thiol groups that are common critical sites for activity of protein tyrosine phosphatases (PTP) making them an important and logical family of target proteins that would explain inhibition of macrophage cytokine production. Of the various PTP, PTP1B has been reported to be irreversibly inhibited by acrolein, but there are no reports that PTP1B is a target of acrolein toxicity in vivo. Since PTP1B is a key regulatory PTP involved in critical pathways and diseases and as a target of acrolein exposure could explain a number of the reported outcomes of acrolein exposure especially at sublethal concentrations. Since the precise mechanism of acrolein toxicity remains uncertain, this project will fill an important gap of knowledge to define in vitro and demonstrate for the first time in vivo, whether inhibition of PTP1B catalytic activity helps define the mechanism of acrolein-induced respiratory toxicity at sublethal concentrations. Studies in Aim 1 will Demonstrate that acrolein blocks the activity of PTP1B in macrophages and epithelial cells in vitro and will be compared to acrolein’s effects on TRPA1. Studies in Aim 2 will demonstrate that sublethal in vivo exposures of acrolein blocks the activity of PTP1B in lung macrophages to decrease inflammatory cytokine release from macrophages. These studies will provide new mechanistic information on acrolein toxicity in vitro and in vivo that will help explain the reported adverse impacts of acrolein exposure and provide guidance to develop medical countermeasures to alleviate the adverse effects of acrolein exposures.