Effects of commercial beverages on the neurobehavioral motility of Caenorhabditis elegans

Abstract

To study the effects of different types of commercially available drinks/beverages on neurobehavior using the model organism C. elegans, and critically review their potential health hazards. Eighteen kinds of beverages from the supermarket were randomly selected and grouped into seven categories namely functional beverage, tea beverage, plant protein beverage, fruit juice beverage, dairy beverage, carbonated beverage and coffee beverage. The pH value, specific gravity and osmotic pressure were also examined. The L4 stage N2 worms were exposed to different concentration of tested beverages (0, 62.5, 125, 250 and 500 µL/mL) for 24 h to measure the survival rate and locomotory behavior such as head thrashing, body bending as well as pharyngeal pumping. All the 18 beverages tested did not induce any visible lethal effects in the nematodes. However, exposure to different types of tested beverages exhibited different effects on the behavioral ability of C. elegans: (1) sports functional beverage and herbal tea drink accelerated the head thrashing and body bending of nematodes when compared to the control group (P < 0.05). (2) The vibration frequency of the pharyngeal pump of nematodes was significantly accelerated after treated with three plant protein beverages (almond milk, coconut milk and milk tea) and dairy products A and B (P < 0.05), and decelerated after treatment with other tested beverages. (3) Carbonated beverage significantly inhibits the head thrashing, body bending and pharyngeal pumping vibration (P < 0.05). Our results indicate that 18 kinds of popular beverages in the market have different influence on the neurobehavior in C. elegans, which may be related to their different components or properties. Further research would be required to conduct a systematic analysis of the effect of beverages by appropriate kinds, taking into consideration other endpoints such as reproduction, lifespan and molecular stress response, etc., and to elucidate the mechanism for its potential health hazards.

Keywords: Behavior; Beverage; C. elegans; Feeding; Nematode.

Figure 1. Beverages exposure affect locomotion frequency in C. elegans.

The x-axis represents the different dose groups of 18 kinds of drinks, and the y-axis represents the ratio of the locomotive frequency of nematodes in each group to that in control group (fold = treated group/control group). (A) An asterisk (*) means head thrash frequency in treated group was higher than that in control group and P < 0.05, # means head thrash frequency in treated group was less than that in control group and P < 0.05. (B) An asterisk (*) means body bend frequency in treated group was higher than that in control group and P < 0.05, # means body bend frequency in treated group was less than that in control group and P < 0.05. (C) An asterisk (*) means pharyngeal pump frequency in treated group was higher than that in control group and P < 0.05, # means pharyngeal pump frequency in treated group was less than that in control group and P < 0.05.

Figure 2. Sports functional beverage and herbal tea drink exposure affect head thrashing and body bending in C. elegans.

(A, B) The frequencies of head thrashes and body bends in 20 s of nematodes treated by sports functional beverage. (C) The frequencies of body bends in 20 s of nematodes treated by herbal tea drink. Data were presented as mean ± SD. * P < 0.05.

Figure 3. Beverages exposure affect pharyngeal pumping in C. elegans.

(A, B, C) The effect on pharyngeal pump frequency of nematodes treated by almond milk, coconut milk and milk tea beverage, respectively. (D & E) The effect on pharyngeal pump frequency of nematodes treated by Prepared milk beverage A and B. Data were presented as mean ± SD. * P < 0.05.

Figure 4. Carbonated drinks exposure affect locomotion in C. elegans.

(A & B) The effect on head thrashes of nematodes treated by brown and colorless carbonated beverages. (C & D) The effect on body bends of nematodes treated by brown and colorless carbonated beverages. (E), (F & G) The effect on pharyngeal pump frequency of nematodes treated by brown, colorless and orange carbonated beverages. Data were presented as mean ± SD. # P < 0.05.