Category: Assay Development and Screening

1225-A - In vivo screening to identify insulin-independent modulators of metabolism identifies novel candidates

Monday, February 5, 2018
2:00 PM - 3:00 PM

Given that 1 in 10 adults in the world will be looking for ways to manage type 2 diabetes by 2040, new therapies for metabolic control hold great socioeconomic significance. Under diabetic conditions, progressive loss of insulin sensitivity in the peripheral tissues results in increasing amounts of insulin being secreted by the beta cells. This compensatory response can ultimately cause beta cell dysfunction. However, increasing evidence suggests that these effects can be reversed to an extent by maintaining glycemic control. Molecules capable of modulating metabolism independent of insulin would open new avenues to managing and treating diabetes. Due to the nature of the disease, there exists no in vitro high throughput screening (HTS) system which can reliably recapitulate whole organism metabolic conditions in diabetes. We developed a novel in vivo HTS strategy for identifying insulin-independent modulators of metabolism by recapitulating some of the features of late stage diabetes, while capitalizing on using the highly amenable model organism - zebrafish.

In order to develop a diabetic model in zebrafish, a CRISPR-Cas9 mediated deletion allele for insulin was generated. Insulin knockout led to a complete absence of detectable Insulin protein in the pancreatic islet. Cells with active insulin promoter activity were detected in the islet of the mutant pancreas, with an islet architecture lacking the typical β cell localization in the core and α cells at the periphery. Mutant animals show defects in lipid and glucose homeostasis and comprehensive phospho-proteomic analyses on whole larvae reveal a major shift in key metabolic processes, including biological transport processes and amino acid metabolism. Using this diabetic model, we developed a 96-well based in vivo screening strategy to identify modulators regulating glucose levels independently of the Insulin receptor signaling axis. The screen revealed several hits, including chemical entities which can be ‘grown’ in different orientations for lead optimization.

In addition to understanding the role of insulin during early development, our study will identify modulators of glucose and lipid metabolism, including molecules that promote glucose uptake in peripheral tissues. Given that this strategy would be the first of its kind to probe for Insulin-independent signaling pathways, our study holds the potential to unravel novel signaling pathways as targets for diabetes therapy, including cases where insulin resistance has already set in.

Sri Teja Mullapudi

Doctoral Student
Max Planck Institute for Heart and Lung Research
Bad Nauhiem, Hessen, Germany

Sri Teja Mullapudi, Doctoral student in Didier Stainier's lab at Max Planck Institute for Heart & Lung Research.
• Ambitious discovery-driven bioengineer, keen on new challenges in R&D, backed by demonstrated ability to propose innovative solutions for complex problems, combined with robust data analysis, award-winning presentation skills and a strong prowess in interpersonal communication
• With a doctorate from the Max Planck Society and trained as a biotechnologist from the Indian Institute for Technology Madras, over 5 years of experience in exhaustive analysis of available literature, developing structured approaches and protocols, and planning and executing time-bound strategies to effectively handle multiple projects
• Recognized for desire to work with and for people, with multiple leadership roles at the institute, regional and national levels and experienced in mentoring students and leading teams