背景:2型糖尿病(T2DM)与代谢综合征密切相关,以胰岛素抵抗为特征,高血糖症,脂质代谢异常,慢性炎症。糖尿病性溃疡(DU)包括由T2DM引起的相应并发症。为了调查,将db/db小鼠用于疾病模型。研究结果表明,由大黄炭交联壳聚糖和丝素蛋白组合制成的支架,指定为RCS/SF,能够改善db/db小鼠糖尿病伤口的愈合过程。然而,以前的研究主要集中在研究RSC/SF支架对伤口愈合的影响,虽然它对整个身体的影响尚未完全阐明。
方法:在本研究中使用冷冻干燥方法制备含有大黄炭的丝素蛋白/壳聚糖海绵支架。随后,在小鼠的背部皮肤上做一个直径为8毫米的切口,将RCS/SF支架直接应用于伤口14天。随后,通过血清和肝脏生化分析评估RCS/SF支架治疗对肝脏脂质代谢的影响,组织病理学,实时定量PCR(qRT-PCR),免疫组织化学,和西方印迹。
结果:RCS/SF支架的使用导致db/db小鼠中与血清糖脂代谢相关的状况增强。对肝组织病理学的评估进一步证实了这种增强。此外,qRT-PCR分析显示,用RCS/SF支架处理导致与脂肪酸合成相关的基因下调,脂肪酸吸收,甘油三酯(TG)合成,糖异生,和炎症因子。此外,通过评估抗氧化酶和脂质过氧化,显示了RCS/SF支架对氧化应激的有益作用。此外,网络药理学分析证实,单磷酸腺苷活化蛋白激酶(AMPK)信号通路在通过利用R.officinale缓解非酒精性脂肪性肝病(NAFLD)方面具有重要功能.AMPK的测量,甾醇调节元件结合蛋白1(SREBP1),脂肪酸合成酶(FASN),乙酰辅酶A羧化酶(ACC)基因和蛋白质表达为这一发现提供了支持。此外,分子对接研究显示大黄的活性成分与AMPK的下游靶标(SREBP1和FASN)之间具有很强的亲和力。
结论:通过调节AMPK信号通路,局部应用的RCS/SF支架有效缓解肝脏脂质积累,减少炎症,并减弱氧化应激。本研究,因此,强调了局部RCS/SF支架在调节肝脂代谢中的关键作用,从而确认了“外部和内部重塑”的概念。
BACKGROUND: Type 2 diabetes mellitus (T2DM) is closely linked to metabolic syndrome, characterised by insulin resistance, hyperglycaemia, abnormal lipid metabolism, and chronic inflammation. Diabetic ulcers (DUs) comprise consequential complications that arise as a result of T2DM. To investigate, db/db mice were used for the disease model. The findings demonstrated that a scaffold made from a combination of rhubarb charcoal-crosslinked chitosan and silk fibroin, designated as RCS/SF, was able to improve the healing process of diabetic wounds in db/db mice. However, previous studies have primarily concentrated on investigating the impacts of the RSC/SF scaffold on wound healing only, while its influence on the entire body has not been fully elucidated.
METHODS: The silk fibroin/chitosan sponge scaffold containing rhubarb charcoal was fabricated in the present study using a freeze-drying approach. Subsequently, an incision with a diameter of 8 mm was made on the dorsal skin of the mice, and the RCS/SF scaffold was applied directly to the wound for 14 days. Subsequently, the impact of RCS/SF scaffold therapy on hepatic lipid metabolism was assessed through analysis of serum and liver biochemistry, histopathology, quantitative real-time PCR (qRT-PCR), immunohistochemistry, and Western blotting.
RESULTS: The use of the RCS/SF scaffold led to an enhancement in the conditions associated with serum glucolipid metabolism in db/db mice. An assessment of hepatic histopathology further confirmed this enhancement. Additionally, the qRT-PCR analysis revealed that treatment with RCS/SF scaffold resulted in the downregulation of genes associated with fatty acid synthesis, fatty acid uptake, triglyceride (TG) synthesis, gluconeogenesis, and inflammatory factors. Moreover, the beneficial effect of the RCS/SF scaffold on oxidative stress was shown by assessing antioxidant enzymes and lipid peroxidation. Additionally, the network pharmacology analysis verified that the adenosine monophosphate-activated protein kinase (AMPK) signalling pathway had a vital function in mitigating non-alcoholic fatty liver disease (NAFLD) by utilizing R. officinale. The measurement of AMPK, sterol regulatory element binding protein 1 (SREBP1), fatty acid synthase (FASN), and acetyl CoA carboxylase (ACC) gene and protein expression provided support for this discovery. Furthermore, the molecular docking investigations revealed a robust affinity between the active components of rhubarb and the downstream targets of AMPK (SREBP1 and FASN).
CONCLUSIONS: By regulating the AMPK signalling pathway, the RCS/SF scaffold applied topically effectively mitigated hepatic lipid accumulation, decreased inflammation, and attenuated oxidative stress. The present study, therefore, emphasises the crucial role of the topical RCS/SF scaffold in regulating hepatic lipid metabolism, thereby confirming the concept of \"external and internal reshaping\".