研究人员对游离脂肪酸有新发现

The current global epidemic ¹ of obesity ²-linked diabetes ³ and its associated consequences -cardiovascular, neurological and renal（肾脏的） diseases -- is a growing public health problem for which therapeutic ⁴ options are limited. In obesity, fatty acids, derived ⁵ mostly from adipose⁶ tissue（脂肪组织）, alter lipid（脂质） metabolism ⁷ in other tissues such as liver and skeletal muscles. Both impaired ⁸ fatty acid metabolism and glucose ⁹ are hallmarks of diabetes., ,In a recent study published in the journal Biochemistry, a research group led by James A. Hamilton, PhD, professor of physiology ¹⁰, biophysics and radiology at Boston University School of Medicine (BUSM), applied ¹¹ novel fluorescent ¹² methods to measure the rate by which fatty acids bind ¹³ to and move across the fatty acid membrane ¹⁴ to become metabolized., ,"Our study shows that fatty acid entry into cells occurs by diffusion ¹⁵ without catalysis by a protein previously ¹⁶ described as a fatty acid transport protein. However, this protein promotes intracellular（细胞间的） metabolism and storage," said Hamilton. "With this advance in basic science, new drugs can be designed that target the exact mechanism ¹⁷ more precisely ¹⁸ than currently available drugs.", ,Previous research has shown that glucose（葡萄糖） transport under the control of insulin is mediated ¹⁹ by a transport protein called GLUT4. However, how fatty acids enter into cells has been an important unsolved problem, especially whether there are gatekeeper plasma ²⁰ membrane proteins that regulate fatty acid translocation across the membrane, thereby ²¹ controlling the supply of fatty acids to the interior of the cell. Although several proteins postulated ²² to be fatty acid transporters have now been shown to have other roles, the mechanistic roles of the protein CD36 have remained elusive ²³ and are widely debated., ,After measuring the products of fatty acid metabolism over time, the researchers found that CD36 enhances fatty acid metabolism into triglycerides (fat deposits), without increasing fatty acid translocation across the membrane in a cell line that does not normally synthesize triglycerides（三酸甘油酯）. Thus, CD36 increases fatty acid uptake by increasing intracellular metabolism, which promotes diffusion of fatty acids into cells.