Department of Experimental Medicine, University of Genoa, Italy | IRCCS Ospedale Policlinico San Martino, Genoa, Italy.
Microrna. 2021;10(4):226-228. doi: 10.2174/2211536611666211228095628.
Despite their biological simplicity, microRNA-based organisms, such as RNA viruses, are currently shown to be unexpected threats to mammals, including humans. This situation is exemplified by the COVID-19 pandemic triggered by the spread of SARS-CoV-2. RNA viruses are older than DNA viruses. Indeed, from an evolutionary standpoint, RNA is an older molecule than DNA. The strength of RNA viruses, compared to DNA viruses, resides in their simplicity and instability. The instability of RNA viruses, such as human immunodeficiency virus (HIV) and flu viruses, generates mutants to escape the host's defense mechanisms. A formidable combination of lethality and infectivity was recently achieved by SARS-CoV-2. Complex DNAbased defense systems use Toll-like receptors to intercept viral RNA inside a cell. Activation of Toll-like receptors triggers inflammation and activates lymphocytes and monocytes, causing thromboxane release. In the case of SARS-CoV-2 infection, this process results in cytokine storms and lung thromboembolism. The ongoing pandemic can be envisioned as a struggle between highly evolved complex DNA organisms, i.e., humans, and poorly evolved simple RNA organisms, i.e., SARS-CoV-2 virus. Quite surprisingly, the complex organism has a serious problem defeating the simplistic organism. However, humans are finally developing a new effective weapon in fighting the SARS-CoV-2 virus, paradoxically, RNA-based vaccines. These considerations underscore the relevance of microRNAs as powerful tools in therapeutic and preventive medicine.
尽管微小 RNA 类生物体（如 RNA 病毒）在生物学上较为简单，但它们目前被证明是对包括人类在内的哺乳动物的意外威胁。这种情况以由 SARS-CoV-2 传播引发的 COVID-19 大流行为例。RNA 病毒比 DNA 病毒出现得更早。实际上，从进化的角度来看，RNA 是比 DNA 更古老的分子。与 DNA 病毒相比，RNA 病毒的优势在于其简单性和不稳定性。RNA 病毒（如人类免疫缺陷病毒 (HIV) 和流感病毒）的不稳定性会产生突变体以逃避宿主的防御机制。SARS-CoV-2 最近实现了致命性和传染性的强大组合。复杂的基于 DNA 的防御系统使用 Toll 样受体在细胞内截获病毒 RNA。Toll 样受体的激活会引发炎症并激活淋巴细胞和单核细胞，导致血栓素释放。在 SARS-CoV-2 感染的情况下，这一过程会导致细胞因子风暴和肺血栓栓塞。目前的大流行可以被视为高度进化的复杂 DNA 生物体（即人类）与进化不良的简单 RNA 生物体（即 SARS-CoV-2 病毒）之间的斗争。令人惊讶的是，复杂的生物体在击败简单的生物体方面存在严重问题。然而，人类最终在对抗 SARS-CoV-2 病毒方面开发出了一种新的有效武器，即基于 RNA 的疫苗。这些考虑强调了微小 RNA 作为治疗和预防医学中强大工具的相关性。
