Antiproliferation Activity and Mechanism of c9, t11, c15-CLNA and t9, t11, c15-CLNA from Lactobacillus plantarum ZS2058 on Colon Cancer Cells.

Qing Ren,Chengli Fu,Bo Yang,Haiqin Chen,Hao Zhang,Guangzhen Zhu,Shunyu Wang,R Paul Ross,Catherine Stanton,Wei Chen

doi:10.3390/molecules25051225

Abstract

Conjugated linolenic acid (CLNA) is a type of ω-3 fatty acid which has been proven to have a series of benefits. However, there is no study about the function of Lactobacillus-derived CLNA isomer. Lactobacillus plantarum ZS2058 has been proven to manifest comprehensive functions and can produce CLNA. To investigate the specific functions of CLNA produced by this probiotic bacterium, two different conjugated α-linolenic acid (CLNA) isomers were successfully isolated. These isoforms, CLNA1 (c9, t11, c15-CLNA, purity 97.48%) and CLNA2 (c9, t11, t15-CLNA, purity 99.00%), both showed the ability to inhibit the growth of three types of colon cancer cells in a time- and concentration-dependent manner. In addition, the expression of MDA in Caco-2 cells was increased by CLNA1 or CLNA2, which indicated that lipid peroxidation was related to the antiproliferation activity of CLNAs. An examination of the key protein of pyroptosis showed that CLNA1 induced the cleavage of caspase-1 and gasdermin-D, while CLNA2 induced the cleavage of caspase-4, 5 and gasdermin-D. The addition of relative inhibitors could alleviate the pyroptosis by CLNAs. CLNA1 and CLNA2 showed no effect on caspase-3, 7, 9 and PARP-1, which were key proteins associated with apoptosis. No sub-diploid apoptotic peak appeared in the result of PI single staining test. In conclusion, CLNA1 activated caspase-1 and induced Caco-2 cell pyroptosis, whereas CLNA2 induced pyroptosis through the caspase-4/5-mediated pathway. The inhibition of Caco-2 cells by the two isomers was not related to apoptosis. This is the first study on the function of Lactobacillus-derived CLNA isomer. The inhibition pathway of Lactobacillus-derived CLNA isomer on colon cancer cells were proved.

Highlights

Conjugated fatty acids (CFAs) are positional and geometric isomers of unsaturated fatty acids that contain one or more non-methylene interrupted double bonds in either the cis or trans forms [1,2,3].One CFA that has been intensively investigated is conjugated linoleic acid (CLA)
The α-linolenic acid was isomerized by L. plantarum ZS2058, and the conjugated α-linolenic acid (CLNA) mixtures were collected from the fermentation
The CLNA1 and CLNA2 were isolated by preparative liquid chromatography (Figure 2a) and their purity were detected by GC-MS

Summary

Introduction

Conjugated fatty acids (CFAs) are positional and geometric isomers of unsaturated fatty acids that contain one or more non-methylene interrupted double bonds in either the cis or trans forms [1,2,3].One CFA that has been intensively investigated is conjugated linoleic acid (CLA). Conjugated fatty acids (CFAs) are positional and geometric isomers of unsaturated fatty acids that contain one or more non-methylene interrupted double bonds in either the cis or trans forms [1,2,3]. Numerous studies have reported that CLA exhibits a variety of health benefits, including anti-cancer [4,5], anti-oxidation [6], anti-atherosclerotic [7], anti-diabetic [8,9], and anti-obesity effects [10,11]. Several plant-derived CLNAs have been studied, including punicic acid (PUA) from pomegranate and trichosanthes; α-eleostearic acid (α-ESA) and β-eleostearic acid (β-ESA) from tung, bitter ground and snake gourd seed; catalpic acid (CA) from catalpa, jacaric acid (JA) from jacaranda; α-calendic acid (α-CDA) and β-calendic acid (β-CDA) from pot marigold [12].

Methods

Results

Conclusion