Background Administration of pancreatic endoplasmic reticulum kinase inhibitor (PERKi) improved insulin secretion and hyperglycemia in obese diabetic mice. In this study, autophagic balance was studied whether to mediate it.
Methods Human islets were isolated from living patients without diabetes. PERKi GSK2606414 effects were evaluated in the islets under glucolipotoxicity by palmitate. Islet insulin contents and secretion were measured. Autophagic flux was assessed by microtubule associated protein 1 light chain 3 (LC3) conversion, a red fluorescent protein (RFP)-green fluorescent protein (GFP)- LC3 tandem assay, and P62 levels. For mechanical analyses, autophagy was suppressed using 3-methyladenine in mouse islets. Small interfering RNA for an autophagy-related gene autophagy related 7 (Atg7) was transfected to interfere autophagy.
Results PERKi administration to mice decreased diabetes-induced P62 levels in the islets. Glucolipotoxicity significantly increased PERK phosphorylation by 70% and decreased insulin contents by 50% in human islets, and addition of PERKi (40 to 80 nM) recovered both. PERKi also enhanced glucose-stimulated insulin secretion (6-fold). PERKi up-regulated LC3 conversion suppressed by glucolipotoxicity, and down-regulated P62 contents without changes in P62 transcription, indicating enhanced autophagic flux. Increased autophagosome-lysosome fusion by PERKi was visualized in mouse islets, where PERKi enhanced ATG7 bound to LC3. Suppression of Atg7 eliminated PERKi-induced insulin contents and secretion.
Conclusion This study provided functional changes of human islets with regard to autophagy under glucolipotoxicity, and suggested modulation of autophagy as an anti-diabetic mechanism of PERKi.
Pancreatic beta cell homeostasis is crucial for the synthesis and secretion of insulin; disruption of homeostasis causes diabetes, and is a treatment target. Adaptation to endoplasmic reticulum (ER) stress through the unfolded protein response (UPR) and adequate regulation of autophagy, which are closely linked, play essential roles in this homeostasis. In diabetes, the UPR and autophagy are dysregulated, which leads to beta cell failure and death. Various studies have explored methods to preserve pancreatic beta cell function and mass by relieving ER stress and regulating autophagic activity. To promote clinical translation of these research results to potential therapeutics for diabetes, we summarize the current knowledge on ER stress and autophagy in human insulin-secreting cells.
Citations
Citations to this article as recorded by
Glucolipotoxicity Suppressed Autophagy and Insulin Contents in Human Islets, and Attenuation of PERK Activity Enhanced Them in an ATG7-Dependent Manner Seoil Moon, Ji Yoon Lim, Mirang Lee, Youngmin Han, Hongbeom Kim, Wooil Kwon, Jin-Young Jang, Mi Na Kim, Kyong Soo Park, Hye Seung Jung Diabetes & Metabolism Journal.2024; 48(2): 231. CrossRef
Endoplasmic reticulum stress: A possible connection between intestinal inflammation and neurodegenerative disorders Giorgio Vivacqua, Romina Mancinelli, Stefano Leone, Rosa Vaccaro, Ludovica Garro, Simone Carotti, Ludovica Ceci, Paolo Onori, Luigi Pannarale, Antonio Franchitto, Eugenio Gaudio, Arianna Casini Neurogastroenterology & Motility.2024;[Epub] CrossRef
Docosahexanoic Acid Attenuates Palmitate-Induced Apoptosis by Autophagy Upregulation via GPR120/mTOR Axis in Insulin-Secreting Cells Seok-Woo Hong, Jinmi Lee, Sun Joon Moon, Hyemi Kwon, Se Eun Park, Eun-Jung Rhee, Won-Young Lee Endocrinology and Metabolism.2024; 39(2): 353. CrossRef
HIV-1 Tat-Mediated Human Müller Glial Cell Senescence Involves Endoplasmic Reticulum Stress and Dysregulated Autophagy Uma Maheswari Deshetty, Nivedita Chatterjee, Shilpa Buch, Palsamy Periyasamy Viruses.2024; 16(6): 903. CrossRef
Gallic acid suppresses the progression of clear cell renal cell carcinoma through inducing autophagy via the PI3K/Akt/Atg16L1 signaling pathway Tianxiang Zhang, Xi Zhang, Yang Fei, Jinsen Lu, Dairan Zhou, Li Zhang, Song Fan, Jun Zhou, Chaozhao Liang, Yang Su International Journal of Oncology.2024;[Epub] CrossRef
Dysregulation of pancreatic β-cell autophagy and the risk of type 2 diabetes Hayder M. Al-kuraishy, Majid S. Jabir, Ali I. Al-Gareeb, Daniel J. Klionsky, Ali K. Albuhadily Autophagy.2024; : 1. CrossRef
Endoplasmic reticulum stress mechanisms and exercise intervention in type 2 diabetes mellitus Qianyu Chen, Xiaoqin Zhao, Zujie Xu, Yiyao Liu Biomedicine & Pharmacotherapy.2024; 177: 117122. CrossRef
Tangningtongluo Tablet ameliorates pancreatic damage in diabetic mice by inducing autophagy and inhibiting the PI3K/Akt/mTOR signaling pathway Ying Ren, Xiangka Hu, Mushuang Qi, Wanjun Zhu, Jin Li, Shuyu Yang, Chunmei Dai International Immunopharmacology.2024; 142: 113032. CrossRef
Ambient air fine particulate matter (PM10 and PM2.5) and risk of type 2 diabetes mellitus and mechanisms of effects: a global systematic review and meta-analysis Salah Azizi, Mohammad Hadi Dehghani, Ramin Nabizadeh International Journal of Environmental Health Research.2024; : 1. CrossRef
Pancreatic islet remodeling in cotadutide-treated obese mice Renata Spezani, Thatiany Souza Marinho, Luiz E. Macedo Cardoso, Marcia Barbosa Aguila, Carlos Alberto Mandarim-de-Lacerda Life Sciences.2023; 327: 121858. CrossRef
Modulation of Unfolded Protein Response Restores Survival and Function of β-Cells Exposed to the Endocrine Disruptor Bisphenol A Laura Maria Daian, Gabriela Tanko, Andrei Mircea Vacaru, Luiza Ghila, Simona Chera, Ana-Maria Vacaru International Journal of Molecular Sciences.2023; 24(3): 2023. CrossRef
Interplay of skeletal muscle and adipose tissue: sarcopenic obesity Min Jeong Park, Kyung Mook Choi Metabolism.2023; 144: 155577. CrossRef
Identification and analysis of type 2 diabetes-mellitus-associated autophagy-related genes Kun Cui, Zhizheng Li Frontiers in Endocrinology.2023;[Epub] CrossRef
Sestrin2 in diabetes and diabetic complications Xiaodan Zhang, Zirui Luo, Jiahong Li, Yaxuan Lin, Yu Li, Wangen Li Frontiers in Endocrinology.2023;[Epub] CrossRef
Crosstalk between autophagy and insulin resistance: evidence from different tissues Asie Sadeghi, Maryam Niknam, Mohammad Amin Momeni-Moghaddam, Maryam Shabani, Hamid Aria, Alireza Bastin, Maryam Teimouri, Reza Meshkani, Hamed Akbari European Journal of Medical Research.2023;[Epub] CrossRef
Beta cell lipotoxicity in the development of type 2 diabetes: the need for species-specific understanding Patricia Thomas, Meurig T. Gallagher, Gabriela Da Silva Xavier Frontiers in Endocrinology.2023;[Epub] CrossRef