Acetylated Chitosan Oligosaccharides Act as Antagonists against Glutamate-Induced PC12 Cell Death via Bcl-2/Bax Signal Pathway
作者:Cui Hao、Lixia Gao、Yiran Zhang、Wei Wang、Guangli Yu、Huashi Guan、Lijuan Zhang、Chunxia Li
DOI:10.3390/md13031267
日期:——
Chitosan oligosaccharides (COSs), depolymerized products of chitosan composed of β-(1→4) d-glucosamine units, have broad range of biological activities such as antitumour, antifungal, and antioxidant activities. In this study, peracetylated chitosan oligosaccharides (PACOs) and N-acetylated chitosan oligosaccharides (NACOs) were prepared from the COSs by chemcal modification. The structures of these monomers were identified using NMR and ESI-MS spectra. Their antagonist effects against glutamate-induced PC12 cell death were investigated. The results showed that pretreatment of PC12 cells with the PACOs markedly inhibited glutamate-induced cell death in a concentration-dependent manner. The PACOs were better glutamate antagonists compared to the COSs and the NACOs, suggesting the peracetylation is essential for the neuroprotective effects of chitosan oligosaccharides. In addition, the PACOs pretreatment significantly reduced lactate dehydrogenase release and reactive oxygen species production. It also attenuated the loss of mitochondrial membrane potential. Further studies indicated that the PACOs inhibited glutamate-induced cell death by preventing apoptosis through depressing the elevation of Bax/Bcl-2 ratio and caspase-3 activation. These results suggest that PACOs might be promising antagonists against glutamate-induced neural cell death.
去乙酰基壳聚糖低聚糖(COSs)是由β-(1→4) d-氨基葡萄糖单元组成的壳聚糖的去聚合产物,具有广泛的生物活性,如抗肿瘤、抗真菌和抗氧化活性。在本研究中,通过化学修饰从COSs制备了全乙酰化壳聚糖低聚糖(PACOs)和N-乙酰化壳聚糖低聚糖(NACOs)。使用核磁共振(NMR)和电喷雾质谱(ESI-MS)鉴定了这些单体的结构。研究了它们对谷氨酸诱导的PC12细胞死亡的拮抗作用。结果表明,PACOs预处理PC12细胞显著抑制了谷氨酸诱导的细胞死亡,并且这种抑制作用呈浓度依赖性。与COSs和NACOs相比,PACOs表现出更好的谷氨酸拮抗作用,表明全乙酰化对壳聚糖低聚糖的神经保护作用至关重要。此外,PACOs预处理显著减少了乳酸脱氢酶的释放和活性氧的产生,并减轻了线粒体膜电位的丧失。进一步的研究表明,PACOs通过抑制Bax/Bcl-2比率升高和半胱天冬酶-3的激活来防止谷氨酸诱导的细胞凋亡。这些结果表明PACOs可能是对抗谷氨酸诱导神经细胞死亡的有前景的拮抗剂。