■在所有年龄段,佛寿作为一种中草药,一直活跃于各种治疗糖尿病的中药配方中。橙皮苷(HES),福寿的主要单体成分,对糖尿病致病机制的干预以及相关并发症的后续治疗进行了广泛的研究。胰岛β细胞对动态调节血糖具有重要作用。这些细胞的功能异常及其死亡与糖尿病的发作密切相关。因此,诱导胰岛内分泌细胞系重新编辑以补充受损的β细胞将是一种有前途的治疗工具。以前,已经发现HES能在体内保护胰岛β细胞,但是,HES在胰岛β细胞中的再生功能及其在促进非β细胞分化为β细胞和细胞命运改写相关机制中的作用尚不清楚。这项工作的重点是研究HES是否可以诱导胰岛α细胞转分化为β细胞以实现受损的β细胞再生,以及该过程中涉及的原因和可能的机制。
■简而言之,在高糖高脂饮食(HFD)饲养的每只雄性C57bL/6J小鼠中,腹膜内给予60mg/kg/d链脲佐菌素(STZ),以创建具有严重β细胞损伤的糖尿病小鼠模型。经过连续28天的HES治疗(160mg/kg;320mg/kg;每天一次,视情况而定)。追踪α和β细胞转化的动力学,通过细胞谱系追踪,以及治疗期间β细胞的生长和凋亡水平。细胞谱系所基于的自我执行转录网络被用作探索潜在机制的线索。广东药学院动物实验伦理委员会(GDPulac2019180)批准了所有动物实验。
■通过细胞谱系定位我们发现,在HES作用下,DM小鼠的胰岛内分泌细胞团中出现了来自α细胞的转分化新生β细胞。与模型组相比,通过Tunel染色和CXCL10水平表达,胰腺β细胞的整体凋亡率降低,HE染色的炎性浸润反馈较低。Ki-67阳性细胞显示β细胞增殖增强。HbA1c和血糖含量降低,升高的C肽和胰岛素含量,对新生β细胞的能力作出反应。也上调了MafA的mRNA水平,Ngn3、PDX-1、Pax4和Arx。此外,TGR5/cAMP-CREB/GLP-1在小鼠肠组织和胰腺组织中GLP-1/GLP-1R和cAMP-CREB/IRS2/PDX-1的表达增加。
■HES直接影响β细胞,除了抗凋亡和减少炎症浸润。HES通过激活DM小鼠中的TGR5受体并调节其应答元件CREB信号传导来促进肠道L细胞释放GLP-1。然后GLP-1使用GLP-1/GLP-1R系统作用于IRS2,IRS2作为影响α前体细胞表达PDX-1的端口,动员Pax4比Arx强表达,使α细胞系最终逆转,实现β细胞内源性增殖。
UNASSIGNED: In all age, FoShou as a Chinese medicinal herb has been active in various kinds of Traditional Chinese medicine formula to treating diabetes. Hesperidin (HES), the main monomeric component of FoShou, has been extensively investigated for interventions with pathogenic mechanism of diabetes as well as subsequent treatment of associated complications. Islet β-cells have an essential effect on dynamically regulating blood sugar. Functional abnormalities in these cells and their death are strongly associated with the onset of diabetes. Therefore, induction of islet endocrine cell lineage re-editing for damaged βcell replenishment would be a promising therapeutic tool. Previously, it has been found that HES can protect islet β-cells in vivo, But, the regenerative function of HES in islet β cells and its role in promoting differential non-β cells transdifferentiation into β cells and cell fate rewriting associated mechanisms remain unclear.This work focused on investigating whether HES can induce islet α cells transdifferentiation into β cells for achieving damaged β cell regeneration and the causes and possible mechanisms involved in the process.
UNASSIGNED: In brief, 60 mg/kg/d streptozotocin (STZ) was administered intraperitoneally in each male C57bL/6J mouse raised by the high-sugar and high-fat diet (HFD) to create a diabetic mouse model with severe β-cell damage. After 28 consecutive days of HES treatment (160 mg/kg; 320 mg/kg; once daily, as appropriate). Tracing the dynamics of α as well as β cell transformation, together with β cells growth and apoptosis levels during treatment by cell lineage tracing. The self-enforcing transcriptional network on which the cell lineage is based is used as a clue to explore the underlying mechanisms. Guangdong Pharmaceutical University\'s Animal Experiment Ethics Committee (GDPulac2019180) approved all animal experiments.
UNASSIGNED: Localization by cell lineage we find that transdifferentiated newborn β-cells derived from α cells appeared in the islet endocrine cell mass of DM mice under HES\'action. Compared to the model group, expressed by Tunel staining and CXCL10 levels the overall apoptosis rate of β-cells of the pancreas were reduced,the inflammatory infiltration feedback from HE staining were lower.Ki-67 positive cells showed enhanced β-cell proliferation. Decreased HbA1c and blood glucose contents, elevated C-Peptide and insulin contents which respond to ability of nascent beta cells. Also upregulated the mRNA levels of MafA, Ngn3, PDX-1, Pax4 and Arx. Moreover, increased the expression of TGR5/cAMP-CREB/GLP-1 in mouse intestinal tissues and GLP-1/GLP-1R and cAMP-CREB/IRS2/PDX-1 in pancreatic tissues.
UNASSIGNED: HES directly affects β-cells, apart from being anti-apoptotic and reducing inflammatory infiltration. HES promotes GLP-1 release by intestinal L cells by activating the TGR5 receptor in DM mouse and regulating its response element CREB signaling. GLP-1 then uses the GLP-1/GLP-1R system to act on IRS2, IRS2 as a port to influence α precursor cells to express PDX-1, with the mobilization of Pax4 strong expression than Arx so that α cell lineage is finally reversed for achieving β cell endogenous proliferation.