A型原花色素(PAC-As)是植物来源的天然多酚,以黄烷-3-醇单体的低聚物或聚合物形式存在,如(+)-儿茶素和(-)-表儿茶素,通过一个不寻常的双A连接。PAC-As存在于树叶中,种子,鲜花,吠叫,和许多植物的果实,并被认为对微生物病原体发挥保护性自然作用,昆虫,和食草动物。因此,当隔离测试时,PAC-As已经显示出几种生物学效应,通过抗氧化剂,抗菌,免疫调节,和抗病毒活性。PAC-事实上已经观察到抑制许多不同人类病毒的复制,包膜和非包膜DNA和RNA病毒均被证明对其抑制作用敏感。机制研究表明,PAC-As导致与它们接触的病毒颗粒的感染性降低,由于它们倾向于与病毒颗粒表面衣壳蛋白或病毒附着和进入所必需的包膜糖蛋白相互作用。由于病毒感染和新病毒爆发是主要的公共卫生问题,开发有效的广谱抗病毒剂(BSAA),即使针对未来的新兴病毒也可以快速部署是当务之急。本文综述了PAC-As的抗病毒活性和作用机制。以及它们作为BSAA针对当前和未来病毒感染的潜力。
A-type proanthocyanidins (PAC-As) are plant-derived natural polyphenols that occur as oligomers or polymers of flavan-3-ol monomers, such as (+)-catechin and (-)-epicatechin, connected through an unusual double A linkage. PAC-As are present in leaves, seeds, flowers, bark, and fruits of many plants, and are thought to exert protective natural roles against microbial pathogens, insects, and herbivores. Consequently, when tested in isolation, PAC-As have shown several biological effects, through antioxidant, antibacterial, immunomodulatory, and antiviral activities. PAC-As have been observed in fact to inhibit replication of many different human viruses, and both enveloped and non-enveloped DNA and RNA viruses proved sensible to their inhibitory effect. Mechanistic studies revealed that PAC-As cause reduction of infectivity of viral particles they come in contact with, as a result of their propensity to interact with virion surface capsid proteins or envelope glycoproteins essential for viral attachment and entry. As viral infections and new virus outbreaks are a major public health concern, development of effective Broad-Spectrum Antiviral Agents (BSAAs) that can be rapidly deployable even against future emerging viruses is an urgent priority. This review summarizes the antiviral activities and mechanism of action of PAC-As, and their potential to be deployed as BSAAs against present and future viral infections.