STUDY: Karnozin EXTRA® alters mitochondrial respiration through its activity on oxidative phosphorylation in human breast cancer cells

Carnosine, a naturally-occurring dipeptide, has been shown to exert an anticancer effect in certain types of cancer by suppressing glycolysis in tumor cells. Glycolysis is one way of energy production predominant in cancer cells. Researchers from Medical Faculty of Novi Sad investigated how Karnozin EXTRA® affects another way of energy production pathway in cancer cells called oxidative phosphorylation. A study led by Jovana Drljača, PhD, analysed whether Karnozin Extra can supress oxydative phosphorylation in human breast cancer cell line (MCF-7).

The results showed that Karnozin EXTRA® (Carnomed) exerted a significant reduction in the oxygen consumption in both cell lines in a dose-dependent manner. Moreover, the activities of mitochondrial electron transport chain complexes I, II and IV in both cell lines were compromised. The strongest inhibitory action was shown on the activity of complex II of mitochondrial electron transport chain.

The graphs below show the results from the study. Figure number 1. shows that tumor cells treated with the highest concentration of Karnozin EXTRA® have almost 4 times lower basal cell respiration in comparison to the control (no treatment).

Figure 1. Basal cell respiration

E1, E2, E3 represent Karnozin EXTRA® in increasing concentrations


Figure 2, 3 and 4 show that Karnozin EXTRA inhibits complexes I,II and IV that transfer electrons in respiratory chain cycle in tumor cells. Thereby, Karnozin EXTRA® inhibits respiration mechanism in MCF-7 tumor cell line.




Figure 2, 3 and 4. Inhibition of Complex I, Complex II and Complex IV

E1, E2, E3 represent Karnozin EXTRA® in increasing concentrations


Figure 5 shows that Karnozin EXTRA® inhibits the maximal capacity of electron transport chain, which means that Karnozin EXTRA decreases the maximal oxygen consumption in tumor cells.

Figure 5. Inhibition of maximal ETS capacity

E1, E2, E3 represent Karnozin EXTRA® in increasing concentrations

This study showed that Karnozin EXTRA® can be a promising new antitumor agent due to its ability to supress energy metabolism in human breast cancer cells. You can read the full abstract here.