State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Screening, School of Life Science and Technology, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China.
Int J Mol Sci. 2018 Mar 22;19(4):943. doi: 10.3390/ijms19040943.
A major source of β cell generation is pancreatic progenitor-like cell differentiation. Multiple studies have confirmed that stem cell metabolism plays important roles in self-renewal and proliferation. In the absence of glucose, glutamine provides the energy for cell division and growth. Furthermore, α-ketoglutarate (αKG), a precursor for glutamine synthesis, is sufficient for enabling glutamine-independent cell proliferation. We have demonstrated that αKG contributes to the large-scale proliferation of pancreatic progenitor-like cells that can provide an ample amount of clinically relevant β cells. We compared the mRNA expression of a subset of genes, the abundance of ATP, reactive oxide species, mitochondrial number, and the colony-forming frequency between mouse pancreatic CD133⁺ and CD133 cells. We employed Real-Time PCR, immunostaining and passage assays to investigate self-renewal and proliferation of pancreatic progenitor-like cells in a 3D culture system in the presence and absence of αKG. The energy metabolism of CD133⁺ cells was more prone to oxidative phosphorylation. However, in the 3D culture system, when αKG was supplemented to the culture medium, the proliferation of the pancreatic progenitor-like cells was significantly elevated. We confirmed that the presence of αKG correlated with the up-regulation of Ten-Eleven Translocation (Tet). αKG can promote the proliferation of pancreatic progenitor-like cells via the up-regulation of Tet.
β 细胞生成的一个主要来源是胰腺祖细胞样细胞的分化。多项研究证实，干细胞代谢在自我更新和增殖中起着重要作用。在没有葡萄糖的情况下，谷氨酰胺为细胞分裂和生长提供能量。此外，谷氨酰胺合成的前体α-酮戊二酸（αKG）足以实现谷氨酰胺非依赖性细胞增殖。我们已经证明，αKG 有助于胰腺祖细胞样细胞的大规模增殖，从而可以提供大量临床相关的β 细胞。我们比较了一组基因的 mRNA 表达、ATP 的丰度、活性氧物质、线粒体数量和 CD133+和 CD133 细胞的集落形成频率。我们采用实时 PCR、免疫染色和传代实验，在存在和不存在 αKG 的情况下，在 3D 培养系统中研究胰腺祖细胞样细胞的自我更新和增殖。CD133+细胞的能量代谢更倾向于氧化磷酸化。然而，在 3D 培养系统中，当向培养基中补充 αKG 时，胰腺祖细胞样细胞的增殖显著增加。我们证实 αKG 的存在与 Ten-Eleven Translocation（Tet）的上调相关。αKG 可以通过上调 Tet 来促进胰腺祖细胞样细胞的增殖。
