Abstract：
BACKGROUND: Dexmedetomidine (DEX), a highly selective α2-adrenergic receptor agonist, is widely used for sedation and anesthesia in patients undergoing hepatectomy. However, the effect of DEX on autophagic flux and liver regeneration remains unclear.
OBJECTIVE: This study aimed to determine the role of DEX in hepatocyte autophagic flux and liver regeneration after PHx.
METHODS: In mice, DEX was intraperitoneally injected 5 min before and 6 h after PHx. In vitro, DEX was co-incubated with culture medium for 24 h. Autophagic flux was detected by LC3-II and SQSTM1 expression levels in primary mouse hepatocytes and the proportion of red puncta in AML-12 cells transfected with FUGW-PK-hLC3 plasmid. Liver regeneration was assessed by cyclinD1 expression, Edu incorporation, H&E staining, ki67 immunostaining and liver/body ratios. Bafilomycin A1, si-GSK3β and Flag-tagged GSK3β, α2-ADR antagonist, GSK3β inhibitor, AKT inhibitor were used to identify the role of GSK3β in DEX-mediated autophagic flux and hepatocyte proliferation.
RESULTS: Pre- and post-operative DEX treatment promoted liver regeneration after PHx, showing 12 h earlier than in DEX-untreated mice, accompanied by facilitated autophagic flux, which was completely abolished by bafilomycin A1 or α2-ADR antagonist. The suppression of GSK3β activity by SB216763 and si-GSK3β enhanced the effect of DEX on autophagic flux and liver regeneration, which was abolished by AKT inhibitor.
CONCLUSIONS: Pre- and post-operative administration of DEX facilitates autophagic flux, leading to enhanced liver regeneration after partial hepatectomy through suppression of GSK3β activity in an α2-ADR-dependent manner.
OBJECTIVE: This study aimed to determine the role of DEX in hepatocyte autophagic flux and liver regeneration after PHx.
METHODS: In mice, DEX was intraperitoneally injected 5 min before and 6 h after PHx. In vitro, DEX was co-incubated with culture medium for 24 h. Autophagic flux was detected by LC3-II and SQSTM1 expression levels in primary mouse hepatocytes and the proportion of red puncta in AML-12 cells transfected with FUGW-PK-hLC3 plasmid. Liver regeneration was assessed by cyclinD1 expression, Edu incorporation, H&E staining, ki67 immunostaining and liver/body ratios. Bafilomycin A1, si-GSK3β and Flag-tagged GSK3β, α2-ADR antagonist, GSK3β inhibitor, AKT inhibitor were used to identify the role of GSK3β in DEX-mediated autophagic flux and hepatocyte proliferation.
RESULTS: Pre- and post-operative DEX treatment promoted liver regeneration after PHx, showing 12 h earlier than in DEX-untreated mice, accompanied by facilitated autophagic flux, which was completely abolished by bafilomycin A1 or α2-ADR antagonist. The suppression of GSK3β activity by SB216763 and si-GSK3β enhanced the effect of DEX on autophagic flux and liver regeneration, which was abolished by AKT inhibitor.
CONCLUSIONS: Pre- and post-operative administration of DEX facilitates autophagic flux, leading to enhanced liver regeneration after partial hepatectomy through suppression of GSK3β activity in an α2-ADR-dependent manner.
摘要：
背景：右美托咪定（DEX），高选择性α2-肾上腺素受体激动剂,广泛用于肝切除术患者的镇静和麻醉。然而,DEX对自噬通量和肝再生的影响尚不清楚.
目的：本研究旨在确定DEX在PHx后肝细胞自噬通量和肝再生中的作用。
方法：在小鼠中，在PHx之前5分钟和之后6小时腹膜内注射DEX。体外，DEX与培养基共孵育24小时。通过原代小鼠肝细胞中的LC3-II和SQSTM1表达水平以及用FUGW-PK-hLC3质粒转染的AML-12细胞中红色斑点的比例检测自噬通量。通过cyclinD1表达评估肝再生，埃杜公司成立，H&E染色,ki67免疫染色和肝脏/身体比率。巴弗洛霉素A1，si-GSK3β和Flag标记的GSK3β，α2-ADR拮抗剂，GSK3β抑制剂，AKT抑制剂用于鉴定GSK3β在DEX介导的自噬通量和肝细胞增殖中的作用。
结果：术前和术后DEX治疗促进PHx后肝再生，显示比未经DEX治疗的小鼠早12小时，伴随着促进的自噬通量，被巴菲霉素A1或α2-ADR拮抗剂完全废除。SB216763和si-GSK3β抑制GSK3β活性增强DEX对自噬通量和肝再生的影响,被AKT抑制剂废除。
结论：术前和术后给予DEX促进自噬通量，通过以α2-ADR依赖性方式抑制GSK3β活性，导致部分肝切除术后肝再生增强。
目的：本研究旨在确定DEX在PHx后肝细胞自噬通量和肝再生中的作用。
方法：在小鼠中，在PHx之前5分钟和之后6小时腹膜内注射DEX。体外，DEX与培养基共孵育24小时。通过原代小鼠肝细胞中的LC3-II和SQSTM1表达水平以及用FUGW-PK-hLC3质粒转染的AML-12细胞中红色斑点的比例检测自噬通量。通过cyclinD1表达评估肝再生，埃杜公司成立，H&E染色,ki67免疫染色和肝脏/身体比率。巴弗洛霉素A1，si-GSK3β和Flag标记的GSK3β，α2-ADR拮抗剂，GSK3β抑制剂，AKT抑制剂用于鉴定GSK3β在DEX介导的自噬通量和肝细胞增殖中的作用。
结果：术前和术后DEX治疗促进PHx后肝再生，显示比未经DEX治疗的小鼠早12小时，伴随着促进的自噬通量，被巴菲霉素A1或α2-ADR拮抗剂完全废除。SB216763和si-GSK3β抑制GSK3β活性增强DEX对自噬通量和肝再生的影响,被AKT抑制剂废除。
结论：术前和术后给予DEX促进自噬通量，通过以α2-ADR依赖性方式抑制GSK3β活性，导致部分肝切除术后肝再生增强。
