Department of Pediatrics, Hirosaki University Hospital, Hirosaki, Japan.
Department of Vascular Biology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Ren Fail. 2021 Dec;43(1):643-650. doi: 10.1080/0886022X.2021.1908901.
Although anti-malarial agents, chloroquine (CQ) and hydroxychloroquine (HCQ) are currently used for the treatment of systemic lupus erythematosus, their efficacy for lupus nephritis (LN) remains unclear. Given that upregulation of glomerular Toll-like receptor 3 (TLR3) signaling plays a pivotal role in the pathogenesis of LN, we examined whether CQ and HCQ affect the expression of the TLR3 signaling-induced representative proinflammatory chemokines, monocyte chemoattractant protein-1 (MCP-1), and C-C motif chemokine ligand 5 (CCL5) in cultured human glomerular endothelial cells (GECs).
We examined the effect of polyinosinic-polycytidylic acid (poly IC), an agonist of TLR3, on MCP-1, CCL5 and interferon (IFN)-β expression in GECs. We then analyzed whether pretreatment with CQ, HCQ, or dexamethasone (DEX) inhibits poly IC-induced expression of these chemokines using real-time quantitative reverse transcriptase PCR and ELISA. Phosphorylation of signal transducers and activator of transcription protein 1 (STAT1) was examined using western blotting.
Poly IC increased MCP-1 and CCL5 expression in a time- and concentration-dependent manner in GECs. Pretreating cells with CQ, but not DEX, attenuated poly IC-induced MCP-1 and CCL5 expression; however, HCQ pretreatment attenuated poly IC-induced CCL5, but not MCP-1. HCQ did not affect the expression of IFN-β and phosphorylation of STAT-1.
Considering that TLR3 signaling is implicated, at least in part, in LN pathogenesis, our results suggest that anti-malarial agents exert a protective effect against the development of inflammation in GECs, as postulated in LN. Interestingly, CQ is a rather powerful inhibitor compared with HCQ on TLR3 signaling-induced chemokine expression in GECs. In turn, these findings may further support the theory that the use of HCQ is safer than CQ in a clinical setting. However, further detailed studies are needed to confirm our preliminary findings.
虽然抗疟药氯喹（CQ）和羟氯喹（HCQ）目前被用于治疗系统性红斑狼疮，但它们对狼疮肾炎（LN）的疗效仍不清楚。鉴于肾小球 Toll 样受体 3（TLR3）信号的上调在 LN 的发病机制中起着关键作用，我们研究了 CQ 和 HCQ 是否影响培养的人肾小球内皮细胞（GEC）中 TLR3 信号诱导的代表性促炎趋化因子单核细胞趋化蛋白-1（MCP-1）和 C-C 基序趋化因子配体 5（CCL5）的表达。
我们研究了 TLR3 激动剂聚肌苷酸-聚胞苷酸（poly IC）对 GEC 中 MCP-1、CCL5 和干扰素（IFN）-β表达的影响。然后，我们分析了 CQ、HCQ 或地塞米松（DEX）预处理是否通过实时定量逆转录 PCR 和 ELISA 抑制 poly IC 诱导的这些趋化因子的表达。使用 Western blot 分析信号转导和转录激活因子 1（STAT1）的磷酸化。
poly IC 以时间和浓度依赖的方式增加 GEC 中 MCP-1 和 CCL5 的表达。用 CQ 预处理细胞，但不是 DEX，可减弱 poly IC 诱导的 MCP-1 和 CCL5 表达；然而，HCQ 预处理可减弱 poly IC 诱导的 CCL5，但不能减弱 MCP-1。HCQ 不影响 IFN-β的表达和 STAT-1 的磷酸化。
鉴于 TLR3 信号至少部分参与 LN 的发病机制，我们的结果表明，抗疟药对 GEC 中炎症的发展具有保护作用，正如 LN 中所假设的那样。有趣的是，与 HCQ 相比，CQ 对 TLR3 信号诱导的 GEC 中趋化因子表达具有更强的抑制作用。反过来，这些发现可能进一步支持在临床环境中使用 HCQ 比 CQ 更安全的理论。然而，需要进一步的详细研究来证实我们的初步发现。
