EGCG Regulates The Dynamic Balance Of Mitochondria And Redox To Influence The Development Of Caenorhabditis Elegans

Epigallocatechin-3-gallate（EGCG）,as a catechin-rich substance in green tea,has a range of biological activities,including antioxidant,anti-inflammatory and anti-radiation.And it is considered to be a major factor in the health benefits of green tea consumption.EGCG has been found to extend the healthy lifespan of adult in Caenorhabditis elegans,but few studies have been conducted about the regulation of EGCG on larva development of C.elegans.In this study,we used in vivo fluorescence imaging technique to explore the regulatory effects of EGCG on epigenetic traits of larva development,and to probe the potential mechanisms of EGCG for health benefits,using C.elegans as a model organism.The main findings are as follows:（1）EGCG inhibited the larvae development of C.elegans in a dose-dependent manner.When the concentration was higher than 20 mmol/L,EGCG was able to completely inhibit the hatchability of C.elegans during embryonic development.At the concentration range of of 2 mmol/L～20 mmol/L,EGCG was able to reduce the hatchability of C.elegans and significantly to inhibit the body size of larvae.2 mmol/L EGCG could significantly inhibit the body size growth and gonadal maturation,and shorten the life span of C.elegans.0.2 mmol/L EGCG could moderately induce the body size reduction,but significantly improved the motility,pharyngeal pump frequency of larval,and prolong the healthy life span of C.elegans.（2）EGCG regulates larval development of C.elegans in relation to reactive oxygen specie（ROS）formation.The antioxidants DL-dithiothreitol（DTT）,N-acetylcysteine（NAC）and ascorbic acid（VC）could significantly alleviate the EGCG-induced body size reduction during larval development.2 mmol/L EGCG induced a dynamic change in H₂O₂ levels and promoted a continuous increase in superoxide anion（O₂˙￣）,which was differed significantly among tissues.（3）EGCG regulates larval development of C.elegans in relation to the morphological homeostasis of mitochondrial.During larval development,the appropriate dose of EGCG can change the mitochondrial shape and promote mitochondrial morphological network.2 mmol/L EGCG could promote mitochondrial morphological fragmentation and disrupt the stress response mechanism of mitochondrial morphological by inhibiting the expression of mitochondrial dynamic regulatory proteins DRP1 and FZO1,which induces mitochondrial dysfunction.（4）Appropriate dose of EGCG could alleviate the adverse effects caused by high dose of EGCG during the larval development of C.elegans.The appropriate dose of EGCG was beneficial to improve the stress adaptation of C.elegans,partially recover the body size reduction induced by high dose of EGCG,and improve the frequency of pharyngeal pump and motility,and the extension of life span.