背景：解毒通络调肝方（JTTF），一种传统的中草药汤剂，表现出通过抑制内质网应激（ERS）和过度自噬来治疗2型糖尿病（T2DM）的潜力，是β细胞异常发育和进展的危险因素。
目的：我们旨在评估JTTF通过抑制ERS和过度自噬对胰腺葡萄糖毒性的影响，其中使用db/db小鼠和INS-1胰岛素瘤细胞。
方法：通过UPLC-Q/TOF-MS分析JTTF的化学成分。糖尿病(db/db)小鼠用蒸馏水或JTTF(2.4和7.2g/kg/天)处理8周。此外，将高葡萄糖（HG）水平诱导的INS-1细胞用或不用JTTF（50、100和200μg/mL）处理48小时，以阐明JTTF对葡萄糖毒性的保护机制。实验方法包括口服葡萄糖耐量试验，苏木精-伊红染色，免疫组织化学，西方印迹,RT-qPCR,和吖啶橙染色。
结果：鉴定了JTTF的28种化学成分。此外,用JTTF治疗显著降低db/db小鼠的血糖症状的严重程度。此外，治疗部分恢复了db/db小鼠的葡萄糖稳态并保护了胰腺β细胞功能.JTTF通过上调GSIS和PDX1、MafAmRNA表达保护INS-1细胞免受HG损伤。Further,用JTTF治疗下调GRP78和ATF6表达，而抑制Beclin-1和LC3激活。该治疗通过下调CaMKKβ/AMPK途径保护细胞免受HG诱导的ERS和过度自噬。
结论：本研究结果表明，JTTF可能通过抑制CaMKKβ/AMPK通路保护β细胞，这加深了我们对JTTF作为T2DM治疗策略的有效性的理解。
BACKGROUND: Jiedu Tongluo Tiaogan Formula (JTTF), a traditional Chinese herbal decoction, exhibits the potential to treat type 2 diabetes mellitus (T2DM) by inhibiting endoplasmic reticulum stress (ERS) and excessive autophagy, which are the risk factors for the abnormal development and progression of β cells.
OBJECTIVE: We aimed to assess the effect of JTTF on pancreatic glucotoxicity by inhibiting ERS and excessive autophagy, for which db/db mice and INS-1 insulinoma cells were used.
METHODS: The chemical composition of the JTTF was analyzed by UPLC-Q/TOF-MS. Diabetic (db/db) mice were treated with distilled water or JTTF (2.4 and 7.2 g/kg/day) for 8 weeks. Furthermore, INS-1 cells induced by high glucose (HG) levels were treated with or without JTTF (50, 100, and 200 μg/mL) for 48 h to elucidate the protective mechanism of JTTF on glucose toxicity. The experimental methods included an oral glucose tolerance test, hematoxylin-eosin staining, immunohistochemistry, western blotting, RT-qPCR, and acridine orange staining.
RESULTS: 28 chemical components of JTTF were identified. Additionally, treatment with JTTF significantly decreased the severity of glycemic symptoms in the db/db mice. Moreover, the treatment partially restored glucose homeostasis in the db/db mice and protected the pancreatic β-cell function. JTTF protected INS-1 cells from HG injury by upregulating GSIS and PDX1, MafA mRNA expression. Further, treatment with JTTF downregulated GRP78 and ATF6 expression, whereas it inhibited Beclin-1 and LC3 activation. The treatment protected the cells from HG-induced ERS and excessive autophagy by downregulating the CaMKKβ/AMPK pathway.
CONCLUSIONS: The present study findings show that JTTF may protects β-cells by inhibiting the CaMKKβ/AMPK pathway, which deepens our understanding of the effectiveness of JTTF as a treatment strategy against T2DM.
