High-Throughput Small Molecule Drug Screening For Age-Related Sleep Disorders Using Drosophila melanogaster

Summary

Presented is a protocol for high-throughput drug screening to improve sleep by monitoring the sleep behavior of fruit flies in an elderly Drosophila model.

Abstract

Sleep, an essential component of health and overall well-being, often presents challenges for older individuals who frequently experience sleep disorders characterized by shortened sleep duration and fragmented patterns. These sleep disruptions also correlate with an increased risk of various illnesses in the elderly, including diabetes, cardiovascular diseases, and psychological disorders. Unfortunately, existing drugs for sleep disorders are associated with significant side effects such as cognitive impairment and addiction. Consequently, the development of new, safer, and more effective sleep disorder medications is urgently needed. However, the high cost and lengthy experimental duration of current drug screening methods remain limiting factors.

This protocol describes a cost-effective and high-throughput screening method that utilizes Drosophila melanogaster, a species with a highly conserved sleep regulation mechanism compared to mammals, making it an ideal model for studying sleep disorders in the elderly. By administering various small compounds to aged flies, we can assess their effects on sleep disorders. The sleep behaviors of these flies are recorded using an infrared monitoring device and analyzed with the open-source data package Sleep and Circadian Analysis MATLAB Program 2020 (SCAMP2020). This protocol offers a low-cost, reproducible, and efficient screening approach for sleep regulation. Fruit flies, due to their short life cycle, low husbandry cost, and ease of handling, serve as excellent subjects for this method. As an illustration, Reserpine, one of the tested drugs, demonstrated the ability to promote sleep duration in elderly flies, highlighting the effectiveness of this protocol.

Introduction

Sleep, one of the essential behaviors necessary for human survival, is characterized by two main states: rapid eye movement (REM) sleep and non-rapid eye movement (NREM) sleep¹. NREM sleep comprises three stages: N1 (the transition between wakefulness and sleep), N2 (light sleep), and N3 (deep sleep, slow wave sleep), representing the progression from wakefulness to deep sleep¹. Sleep plays a crucial role in both physical and mental health². However, aging reduces total sleep duration, sleep efficiency, slow-wave sleep percentage, and REM sleep percentage in adults³. Older ....

Protocol

This protocol uses the 30-day-old w¹¹¹⁸ flies from the Bloomington Drosophila Stock Center (BDSC_3605, see Table of Materials).

1. Preparation of the aged fruit flies

1. Food preparation
   1. Prepare standard corn starch culture medium by mixing 50 g/L cornflakes, 110 g/L sugar, 5 g/L agar, and 25 g/L yeast. Heat the cornflakes and yeast with water to gelatinize, and then fully dissolve all the substances.

Discussion

The described method is suitable for rapidly screening small and medium-sized sleep drugs. Currently, most mainstream high-throughput drug screening methods are based on biochemical and cellular levels. For example, the structure and properties of the receptor are examined to search for specific ligands that can bind to it²². Another approach involves analyzing the binding mode and strength of molecular fragments of selected drugs using Nuclear Magnetic Resonance (NMR) with mass spectrometry

Materials

Name	Company	Catalog Number	Comments
Ager	BIOFROXX	8211KG001
Artificial Climate Box	PRANDT	PRX-1000A	official website:https://www.nbplt17.com/PLTXBS-Products-20643427/
DAM2 Drosophila Activity Monitor	TriKineics	DAM2	official website:https://www.trikinetics.com/
DAM2system	TriKineics	version:v3.03	official website:https://www.trikinetics.com/
DAMFileScan	TriKineics	version:1.0.7.0	official website:https://www.trikinetics.com/
Dimethyl Sulfoxide	SIGMA	276855
Drosophila Activity Monitoring Incubator	Tritech Research	DT2-CIRC-TK	official website:https://www.tritechresearch.com/DT2-CIRC-TK.html
Drosophila Bottles	Biologix	51-17720	official website:http://biologixgroup.com/goods.php?id=48
Drosophila: w1118	Bloomington Drosophila Stock Center	BDSC_3605
Excel	Microsoft	version:Excel 2016	official website:https://www.microsoftstore.com.cn/software/office/excel
Glass tubes	TriKinetics	PPT5x65	official website:https://www.trikinetics.com/
MATLABR2022b	MathWorks	version:9.13.0.2049777	official website:https://ww2.mathworks.cn/products/matlab.html
Prism	GraphPad	Version:Prism 8.0.1	official website:https://www.graphpad.com/features
Reserpine	MACKLIN	R817202-1g
Saccharose	SIGMA	1245GR500
SCAMP	Vecsey Lab	N/A	official website:https://academics.skidmore.edu/blogs/cvecsey/