EVALUATING HEARTBEAT-RESTORING EFFECTS OF ANTIOXIDANT DIETARY SUPPLEMENTS USING DAPHNIA MAGNA

Many phytochemical compounds have been claimed to induce beneficial effects to human health because of high antioxidants and other flavonoid molecules. Some of these products claim to work like a panacea that can treat multiple chronic diseases such as cancer, hypertension, diabetes and weak immunity. Despite of so many unproven claims, there has not been a reliable bioassay that can verify these claims from any aspect. Compared to the seriousness on the reality of verifying the benefits from most antioxidant products, almost no method has been found for this unique method that was devised and tested as an experimental modality.

Daphnia was chosen for the ease of hearbeat evaluation with relatively low-level magnification under an optical microscopy. It assumed that the cardiac stress might induce the perturbation in heartbeat rate and its body system should require increased ATPs to keep their heartbeat constant. The increased ATPs should be generated in mitochondrial structures, where possibly more oxidants should be generated. And, our antioxidant products might reduce the oxidant burden so to make the hearbeat to normal faster. This study was performed to find a proof of concept as a bioassay using an invertebrate model, assumably though not directly related to the effects on humans. The ability of antioxidants to restore once-stressed cardiac activity was studied by monitoring heartbeat change. Three popular antioxidant materials were chosen to investigate: propolis, acai berry, and ginseng extract. The materials we chose were expected to restore the heartbeat of daphnia fast after its heartbeat varied under the acute incubation in alcohol solutions and culturing water at low pH, or low temperature.

Result indicated that mean restoration rates were 2.0 ~ 3.0 times greater in the solutions of antioxidant materials, compared to that in culturing water. A similar trend was found for the different conditions of stress such as alcohol solution, culturing water in low pH, or cold temperature. The study concluded that the antioxidant solutions expedited the heartbeat stabilization with some beneficial effects to the cardiac functions of daphnia. The study might find a useful tool of applying the physiology of daphnia for verifying the beneficial effects of various dietary supplements.