The Lipids paper of the month, selected by Editor-in-Chief Eric Murphy, is "Berberine inhibits oxygen consumption rate independent of alteration in cardiolipin levels in H9c2 cells" by Grant Hatch at the University of Manitoba, in Canada, and colleagues. Berberine is a plant alkaloid that reduces blood glucose levels to a similar extent as the commonly used anti-diabetes drug metformin. However, some studies suggest a negative impact of berberine on cell proliferation via an alteration in mitochondrial function. Using H9c2 cardiac myocytes, Hatch and colleagues demonstrate that berberine results in a rapid, concentration-dependent reduction in the mitochondrial oxygen consumption rate. Because cardiolipin is a mitochondrial phospholipid essential for mitochondrial function, the researchers assessed the impact of berberine on cardiolipin metabolism and levels. Although cardiolipin levels were unchanged, cardiolipin fatty acid recycling was altered in a manner that could impact mitochondrial protein kinase C δ distribution. Collectively, these changes may account for reduced mitochondrial function. "This paper expands our understanding of how berberine, a widely available herbal supplement, may have a substantial impact on heart health via an untoward impact on heart mitochondrial function," says Murphy. This paper is available for free download through March 16.