Impaired and limited metabolism is a central feature of Barth syndrome, with implications in how our affected individuals eat, sleep, and function. A key challenge in our field is understanding how a dysfunctional enzyme (tafazzin, TAZ) and its abnormal lipid product (cardiolipin, CL) results in altered metabolism. Although much has been impacted by COVID, our research community continues to forge forward in addressing this critical question.
Recently published work by BSF’s Scientific Medical Advisory Board (SMAB) member Dr. Todd Cade and colleagues – and involving the participation of five of our affected individuals – has shown that the uptake and distribution of the amino acid arginine differed when compared to healthy controls. Given the reliance of Barth cells on metabolizing proteins and sugar to generate energy, Dr. Cade’s results continue to build on his body of Barth metabolic understanding and set the stage for further research into how arginine and other amino acids play a role in the manifestation and symptomology of Barth syndrome.
Published in January 2021, Dr. Laura Cole, SMAB member Dr. Grant Hatch, and colleagues demonstrate a critical role for TAZ in regulating insulin release from the pancreatic Beta-cells. Utilizing TAZ knockdown mice, Dr. Cole found that while the total number of Beta-cells was unaffected, the amount of insulin they released as well as overall mitochondrial function were reduced when compared to controls. The exact mechanism of how loss of TAZ function results in impaired insulin secretion (and therefore glucose metabolism) merits further research, as Dr. Cade’s previous work showed the unusually high dependence of our affected individuals on glucose for energy.