Humans have two kinds of fat – white fat, which stores energy in the form of triglycerides, and brown fat, which dissipates stored energy as heat. White fat can be converted to brown fat, but until this past week, no one was sure how the process happened.
Domenico Accili, MD, is the leader of the study at UC San Francisco, and the Russell Berrie Foundation Professor at CUMC. He said of the experiment, “Turning white fat into brown fat is an appealing therapeutic approach to staunching the obesity epidemic, but it has been difficult to do so in a safe and effective way.”
Thiazolidinediones (TZDs), a class of drugs that includes the highly controversial Actos and Avandia, turn white fat cells into brown fat through a cell receptor called peroxisome proliferator-activated receptor-gamma (ppar-gamma). However, the exact method for this transformation was unclear, although TZDs have been used to treat diabetes for years. Because of numerous medical problems, including liver failure, heart disease, bladder cancer (in Actos), bone loss, and even weight gain, researchers wanted to find a safer way to convert white fat to brown.
The team of researchers at UC San Francisco initially found a group of enzymes in mice called sirtuins (Sir2) which increased metabolic activity. They have now confirmed that these enzymes work with ppar-gamma to convert white fat cells into brown fat.
Dr. Accili says, “Our findings have two important implications … First, they suggest that TZDs may not be so bad – if you can find a way to tweak their activity. Second, one way to tweak their activity is by using sirtuin agonists – that is, drugs that promote sirtuin activity.”
The research has been published in an online version of Cell, at a time when litigation against one particular TZD drug, Actos, is heating up. Judge Rebecca Doherty presides over MDL 2299, in Louisiana (Lafayette), the multidistrict litigation against Takeda Pharmaceuticals. Several diabetes patients who took Actos for several years are suing the pharmaceutical company, alleging that Takeda knew there was a link between bladder cancer and their drug, and they did nothing to warn patients or doctors of the danger.
The experienced lawyers at Strom Law, LLC, are now accepting cases against Takeda Pharmaceuticals nationwide. If you or a loved one have Type 2 diabetes, taken Actos as part of your treatment, and have been diagnosed with failing vision, liver problems, heart disease, or bladder cancer, you may be entitled to compensation. Please contact us today for a free consultation. 803.252.4800.
