Triacylglycerols are a source of fatty acyl CoA and serve as stores of energy in organisms. They are mobilized during conditions of stress and high-energy activity for efficient energy production. Defects in mobilizing triacylglycerol results in several human disorders such as obesity, metabolic syndrome and is a complication of diabetes and cardiovascular disorders. The sphingolipid ceramide affects cellular energy metabolism by interfering with mitochondrial function. In a Drosophila model that accumulates ceramide, we investigated how it adapts to compromised energy levels and discovered AKT/FOXO regulated novel lipases that mobilize and integrate the use of triglycerides for energy consuming processes. Impairment of the function of these lipases leads to elevated triglycerides, increased sensitivity to starvation and cardiac dysfunction. Our data indicate the existence of a lipolytic pathway functioning across different organs that includes the two novel lipases and is active under both physiological and stress conditions. The goal of this proposal is to elucidate the mechanisitic details involved in the complex functioning of these lipases in physiological as well as pathological states that are associated with hypertriglyceridemia.
The specific aims of this project are (1). Gain insight into the non-autonomous mode of action of CG8093 and CG6277 lipases (2). Identify components and pathways involved in the regulation of triglycerides by CG8093 and CG6277 through a genetic approach (3). Evaluate the role of CG8093 and G6277 lipases in hypertriglyceridemia associated with obesity and diabetes using Drosophila and mouse models. Upon completion of these aims, we hope to gain considerable insight into the mechanism of action of these lipases and their contribution to energy metabolism in physiological and stress conditions and identify components and pathways involved in the functioning of these lipases.

Public Health Relevance

Triglycerides are a type of fat that the body uses as a major source of energy. The synthesis and breakdown of triglycerides is crucial because it ensures that sufficient energy is available to the body during starvation or times of increased energy need. However elevated triglyceride level is an important contributor to metabolic syndrome, which raises the risk factor for developing heart disease and type II diabetes. Therefore, it is important to understand the cellular machinery involved in maintaining triglyceride homeostasis. This project investigates the mechanisms of novel lipases involved in the breakdown of triglycerides in normal and pathological states.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM110288-04
Application #
9469526
Study Section
Molecular and Integrative Signal Transduction Study Section (MIST)
Program Officer
Koduri, Sailaja
Project Start
2015-08-01
Project End
2019-04-30
Budget Start
2018-05-01
Budget End
2019-04-30
Support Year
4
Fiscal Year
2018
Total Cost
Indirect Cost
Name
University of Massachusetts Medical School Worcester
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
603847393
City
Worcester
State
MA
Country
United States
Zip Code
Kunduri, Govind; Turner-Evans, Daniel; Konya, Yutaka et al. (2018) Defective cortex glia plasma membrane structure underlies light-induced epilepsy in cpes mutants. Proc Natl Acad Sci U S A 115:E8919-E8928