Photobiomodulation therapy decreases free fatty acid generation and release in adipocytes to ameliorate insulin resistance in type 2 diabetes

Excessive circulating free fatty acids (FFA) cause insulin resistance in peripheral tissues by inhibiting the proximal insulin signaling pathway. White adipose tissue (WAT) is a primary source of FFA generation and release through triglyceride (TG) hydrolysis. Thus, reducing excessive lipolysis in adipocytes ameliorates whole-body insulin resistance in type 2 diabetes. Here, we found that a noninvasive photobiomodulation therapy (PBMT), decreased FFA generation and release in WATs from high-fat diet (HFD)-fed mice and diabetic db/db mice. Meanwhile, plasma FFA and TG levels were reduced in two mouse models after PBMT. PBMT promoted mitochondrial reactive oxygen species (ROS) generation, which inhibited phosphatase and tensin homologue (PTEN) and promoted protein kinase B (AKT) activation.