Abstract:
Rationale: NLRP3 inflammasome is critical in the development and progression of many metabolic diseases driven by chronic inflammation, but its effect on the pathology of postmenopausal osteoporosis (PMOP) remains poorly understood. Methods: We here firstly examined the levels of NLRP3 inflammasome in PMOP patients by ELISA. Then we investigated the possible mechanisms underlying the effect of NLRP3 inflammasome on PMOP by RNA sequencing of osteoblasts treated with NLRP3 siRNA and qPCR. Lastly, we accessed the effect of decreased NLRP3 levels on ovariectomized (OVX) rats. To specifically deliver NLRP3 siRNA to osteoblasts, we constructed NLRP3 siRNA wrapping osteoblast-specific aptamer (CH6)-functionalized lipid nanoparticles (termed as CH6-LNPs-siNLRP3). Results: We found that the levels of NLRP3 inflammasome were significantly increased in patients with PMOP, and were negatively correlated with estradiol levels. NLRP3 knock-down influenced signal pathways including immune system process, interferon signal pathway. Notably, of the top ten up-regulated genes in NLRP3-reduced osteoblasts, nine genes (except Mx2) were enriched in immune system process, and five genes were related to interferon signal pathway. The in vitro results showed that CH6-LNPs-siNLRP3 was relatively uniform with a dimeter of 96.64 ± 16.83 nm and zeta potential of 38.37 ± 1.86 mV. CH6-LNPs-siNLRP3 did not show obvious cytotoxicity and selectively delivered siRNA to bone tissue. Moreover, CH6-LNPs-siNLRP3 stimulated osteoblast differentiation by activating ALP and enhancing osteoblast matrix mineralization. When administrated to OVX rats, CH6-LNPs-siNLRP3 promoted bone formation and bone mass, improved bone microarchitecture and mechanical properties by decreasing the levels of NLRP3, IL-1β and IL-18 and increasing the levels of OCN and Runx2. Conclusion: NLRP3 inflammasome may be a new biomarker for PMOP diagnosis and plays a key role in the pathology of PMOP. CH6-LNPs-siNLRP3 has potential application for the treatment of PMOP.
摘要:
原理:NLRP3炎性体在许多由慢性炎症引起的代谢性疾病的发展和进展中至关重要,但是其对绝经后骨质疏松症(PMOP)病理的影响仍然知之甚少。方法:我们首先通过ELISA检测PMOP患者中NLRP3炎性体的水平。然后,我们通过对NLRP3siRNA和qPCR处理的成骨细胞进行RNA测序,研究了NLRP3炎性体对PMOP影响的可能机制。最后,我们研究了NLRP3水平降低对去卵巢(OVX)大鼠的影响.为了将NLRP3siRNA特异性递送至成骨细胞,我们构建了包裹成骨细胞特异性适体(CH6)功能化脂质纳米粒(称为CH6-LNPs-siNLRP3)的NLRP3siRNA。结果:我们发现PMOP患者NLRP3炎性体水平显著升高,与雌二醇水平呈负相关。NLRP3敲低影响信号通路,包括免疫系统过程,干扰素信号通路。值得注意的是,在减少NLRP3的成骨细胞中,9个基因(除Mx2外)在免疫系统过程中被富集,5个基因与干扰素信号通路相关。体外结果表明,CH6-LNPs-siNLRP3相对均匀,读数为96.64±16.83nm,ζ电位为38.37±1.86mV。CH6-LNP-siNLRP3没有显示出明显的细胞毒性,并且选择性地将siRNA递送至骨组织。此外,CH6-LNPs-siNLRP3通过激活ALP和增强成骨细胞基质矿化刺激成骨细胞分化。当给OVX大鼠服用时,CH6-LNPs-siNLRP3促进骨形成和骨量,通过降低NLRP3,IL-1β和IL-18的水平以及增加OCN和Runx2的水平来改善骨骼的微观结构和机械性能。结论:NLRP3炎性体可能是PMOP诊断的新生物标志物,在PMOP的病理过程中起关键作用。CH6-LNPs-siNLRP3在治疗PMOP方面具有潜在的应用价值。