The Effects of Blackcurrant and Berry Extracts on Oxidative Stress in Cultured Cardiomyocytes and Microglial Cells
Authors: Currie Tanisha L. , Engler Marguerite M. , Olsen Cara H. , Krauthamer Victor , Scott Jonathan M. , Deuster Patricia A. , Flagg Thomas P. 
Published: May 2022

Background

Cardiovascular disease (CVD) is the number one cause of morbidity and mortality for both men and women in the U.S; to include our military. Warfighters consistently serve in harm’s way due to their national security mission to deter the enemy’s threats and protect our homeland security. With these high stakes, operational demands impose stressors related to military deployment, and consequently physiological changes related to brain and heart health. All together these processes may also impact operational readiness. Oxidative stress is an key underlying factor in atherosclerosis and cognitive decline. It occurs at the cellular level with an imbalance between reactive oxygen species and reactive nitrogen species, and/or a deficiency in antioxidant systems. Mounting evidence suggests flavonoids, in the form of berry extracts, may promote cell health by exerting antioxidant properties.

Methods

The effects of blackcurrant and various berry extracts were tested in two different cultured cell lines ‐ cardiomyocyte (HL‐1) and microglia (BV‐2) cells ‐ to study their biological effects. The principal ingredients in blackcurrant and cranberry extract – delphinidin 3‐rutinoside (D3R) and cyanidin 3‐glucoside (C3G), respectively—were also assessed. Our primary outcome was oxidative stress. A menadione‐induced oxidative stressor was used and its output was quantified using a green fluorogenic probe to detect oxidative stress (CellROXTM). Control substances included N‐acetyl‐cysteine (NAC).

Results

Blackcurrant extracts had similar antioxidant effects as N‐acetyl‐cysteine (NAC) in HL‐1 cells with regard to cellular protection and antioxidant protection, whereas cranberry extract was ineffective. In contrast, cranberry extract was comparable to blackcurrant extract in BV‐2 cells. As for the bioactive ingredients, results showed that D3R and C3G reduced oxidative stress, which were similar to whole berry extracts. This indicates that these ingredients likely contribute to the antioxidant properties of berries.

Conclusion

In summary, we demonstrated that both blackcurrant and cranberry extracts can reduce oxidative stress. Overall, blackcurrant extract was more effective in reducing oxidative stress in the HL‐1 cells, whereas cranberry extract was more effective in reducing oxidative stress in the BV‐2 cells. These results suggest specific cardio and neuroprotective benefits of berry flavonoids. Berry flavonoids also demonstrated promising effects as potent antioxidants. Future research should explore dose response, cell viability, and bioavailability in cellular and human models.

Disclaimer

The opinions and assertions expressed herein are those of the author(s) and do not necessarily reflect the official policy or position of the Uniformed Services University or the Department of Defense.

Conflict of Interest

Neither I nor my family members have a financial interest in any commercial product, service, or organization providing financial support for this research.