La Rosa Francesca, Mancuso Roberta, Agostini Simone, Piancone Federica, Marventano Ivana, Saresella Marina, Hernis Ambra, Fenoglio Chiara, Galimberti Daniela, Scarpini Elio, Clerici Mario
IRCCS Fondazione Don C. Gnocchi, ONLUS, 20148 Milan, Italy.
Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy.
Pharmaceuticals (Basel). 2021 Nov 20;14(11):1187. doi: 10.3390/ph14111187.
Activation of the NLRP3 inflammasome complex results in the production of IL-18, Caspase-1 and IL-1β. These cytokines have a beneficial role in promoting inflammation, but an excessive activation of the inflammasome and the consequent constitutive inflammatory status is a negative factor in human pathologies including Alzheimer's Disease (AD). MicroRNAs (miR-NAs) target the 3'UTR region of NLRP3, preventing the activation of the inflammasome and inhibiting cytokine production. Because Stavudine (D4T), an antiretroviral drug, was recently shown to reduce inflammasome activation, we verified whether its effect is mediated by miR-7-5p, miR-22-3p, miR-30e-5p and miR-223-3p: miRNAs that bind the -mRNA-UTR region and interfere with protein translation, reducing NLRP3 activation. Peripheral blood mononuclear cells (PBMCs) of twenty AD patients and ten sex-matched Healthy Controls (HC) were stimulated with Lipopolysaccharides (LPS)+Amyloid-beta (Aβ) in the absence/presence of D4T. Expression of genes within the inflammasome complex and of miRNAs was evaluated by RT-PCR; cytokines and caspase-1 production was measured by ELISA. Results have shown that: NLRP3, ASC, IL-1β and IL-18 expression, as well as IL-18, IL-1β and caspase-1 production, were significantly augmented ( < 0.05) in LPS+Aβ-stimulated PBMCs of AD patients compared to HC. D4T reduced the expression of inflammasome genes and cytokine production ( < 0.005). miR-7-5p and miR-223-3p expression was significantly increased in LPS+Aβ-stimulated PBMCs of AD patients ( < 0.05), and it was reduced by D4T in AD alone. In conclusion: miR-223-3p and mir-7-5p expression is increased in AD, but this does not result in down-regulation of NLRP3 inflammasome expression and of IL-1β and IL-18 production. D4T increased miRNA expression in HC but had an opposite effect in AD, suggesting that miRNA regulatory mechanisms are altered in AD.
NLRP3炎性小体复合物的激活会导致白细胞介素-18（IL-18）、半胱天冬酶-1（Caspase-1）和白细胞介素-1β（IL-1β）的产生。这些细胞因子在促进炎症方面具有有益作用，但炎性小体的过度激活以及随之而来的持续性炎症状态在包括阿尔茨海默病（AD）在内的人类疾病中是一个负面因素。微小RNA（miRNA）靶向NLRP3的3'非翻译区（3'UTR），阻止炎性小体的激活并抑制细胞因子的产生。由于抗逆转录病毒药物司他夫定（D4T）最近被证明可降低炎性小体的激活，我们验证了其作用是否由miR-7-5p、miR-22-3p、miR-30e-5p和miR-223-3p介导：这些miRNA与-mRNA-UTR区域结合并干扰蛋白质翻译，从而降低NLRP3的激活。在有/无D4T的情况下，用脂多糖（LPS）+β淀粉样蛋白（Aβ）刺激20例AD患者和10例性别匹配的健康对照（HC）的外周血单个核细胞（PBMC）。通过逆转录聚合酶链反应（RT-PCR）评估炎性小体复合物内基因和miRNA的表达；通过酶联免疫吸附测定（ELISA）测量细胞因子和半胱天冬酶-1的产生。结果表明：与HC相比，在LPS+Aβ刺激的AD患者PBMC中，NLRP3、凋亡相关斑点样蛋白（ASC）、IL-1β和IL-18的表达以及IL-18、IL-1β和半胱天冬酶-1的产生均显著增加（<0.05）。D4T降低了炎性小体基因的表达和细胞因子的产生（<0.005）。在LPS+Aβ刺激的AD患者PBMC中，miR-7-5p和miR-223-3p的表达显著增加（<0.05），而在单独的AD中，D4T使其降低。总之：AD中miR-223-3p和mir-7-5p的表达增加，但这并未导致NLRP3炎性小体表达以及IL-1β和IL-18产生的下调。D4T增加了HC中miRNA的表达，但在AD中产生了相反的效果，表明AD中miRNA的调节机制发生了改变。
