Investigation of flow cytometry analysis linear and cyclic analogues of Carnosine and inverse Carnosine on cancerous cells HepG2 and HT-29

Carnosine (β-alanyl-L-histidine) is a naturally occurring dipeptide widely and abundantly distributed in the muscle and nervous tissues of animal species. Carnosine contains several beneficial biological properties such as antiglycating and antioxidant activities. It also contains antineoplastic effects in human cell culture as well as in animal experiments. In order to further examine structural basis of Carnosine with the anticancer activity, some liner and cyclic Carnosine peptide analogues and inverse Carnosine were synthesized, using solid-phase peptide synthesis strategy, and their effects as anti-neoplastic agents were examined on cancer cell lines of HepG2 (Human Liver Cancer Cell Line) and HT-29 (Human Colorectal Adenocarcinoma Cell Line) using flow cytometry analysis. Flow cytometry analysis was determined by analytical DNA flow cytometry. HepG2 and HT-29 cells were harvested and adjusted to 104 cells/mL and then incubated for 6h with 10μg/mL of linear and cyclic peptides. The cells were centrifuged at high speed (12,000 rpm) for 20s. The signals obtained in H-1 area mean that PI was able to enter the cells and bind to DNA and so apoptosis has occurred, whereas, the signals appeared in H-2 area indicate that the cancerous cells treated with linear and cyclic peptides remained intact and so no apoptosis has happened.

Keywords:

Linear and cyclic peptide , Solid phase , Macrocyclization , Flow cytometry , apoptosis