ANALYSIS OF THE PALMITOYL PEPTIDE EFFECT ON ZEBRAFISH (DANIO RERIO) LARVAE LOCOMOTION AND CAUDAL FIN REGENERATION

• Main Author: Sukmanaputra, Teguh
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/78279
• Institution: Institut Teknologi Bandung

Oxidative stress due to UV exposure can trigger an increase in reactive oxygen species (ROS) and stimulate matrix metalloproteases (mmps) gene expression in the skin, resulting in excessive skin aging. Palmitoil Tripeptida-5 (PT-5) and Palmitoil Tripeptida-8 (PT-8) are synthetic peptides used in anti-aging products because they are believed to be able to repair and increase collagen synthesis by reducing mmps gene expression. Although PT5 and PT8 have been clinically tested, their performance is still limited in chronic inflammatory diseases. Meanwhile, how these two peptides affect the decrease in mmps expression has not yet been done. This study aims to determine the lethal concentration 50 (LC50) toxicity of PT-5 and PT-8, and examine the effect of PT-5 and PT-8 at LC25 concentrations in-vivo on regeneration and locomotion of zebrafish larvae (Danio rerio). Toxicity tests were conducted using the Fish Embryo Acute Toxicity Test (FET) method based on OECD test No. 236. Regeneration analysis was performed by amputating the caudal fin of zebrafish larvae up to the fin pigment gap and then incubated for 2- and 4-days post amputation (dpa) in 3 treatment mediums (E3 as control, PT-5 LC25, and PT-8 LC25) using 9 zebrafish larvae aged 3-days post fertilization (dpf) in each treatment. Swimming locomotion analysis was conducted by recording the locomotion of zebrafish larvae that had been incubated in the treatment medium for 72 hours and then the distance, speed, and trajectory were analyzed using RStudio. The toxicity test results showed that the LC50 of PT-5 was 33.544 ppm and LC25 was 28.105 ppm, while the LC50 of PT-8 was 2.936 ppm and LC25 was 2.388 ppm. The results of swimming locomotion analysis showed that the administration of PT-5 28.105 ppm and PT-8 2.388 ppm can significantly reduce the distance traveled and the speed of locomotion of zebrafish larvae when compared to the control group. The results of zebrafish caudal fin regeneration study showed that 28,105 ppm PT-5 and 2,388 ppm PT-8 could significantly increase the blastema area after 2-dpa. In addition, the administration of PT-5 and PT-8 resulted in significantly larger size of regenerating caudal fins after 4-dpa than the control group. However, observation of the tail fin structure of zebrafish larvae after post-amputation administration of PT-5 and PT-8 showed an irregular structure as in the control group. This may be due to the decrease in mmps expression that can increase the overexpression of col1a so that it can change the structure of the collagen that makes up the tail fin. Overall, this study shows that PT-5 and PT-8 have the potential to reduce mmps.