Leong PK, Ko KM
 Division of Life Science, Hong Kong University of Science & Technology, Clear Water Bay, Hong Kong, China
Based on traditional Chinese medicine (TCM) theory, Yang and Qi are the driving forces of physiological functions in the body, by the virtue of their role in regulating mitochondrial function. While the biochemical basis of Yang-invigoration primarily involves a stimulation of mitochondrial adenosine triphosphate generation capacity (GC) via fluidizing the mitochondrial inner membrane, Qi-invigoration elicits a glutathione-dependent antioxidant response, presumably via activating nuclear factor (erythroid-derived 2)-like 2 (the master regulator of antioxidant gene expression). In this regard, Yang-invigorating herbs can increase mitochondrial ATP production whereas Qi-invigorating herbs preserve the structural integrity of mitochondria in the presence of oxidative stress. Accumulating evidence has shown that type 2 diabetes, which is mainly caused by over-nutrition, is associated with mitochondrial dysfunction. As a result of mitochondrial lesions and the pathogenesis of diabetes, complications, such as cardiomyopathy and nephropathy, are major causes of morbidity and mortality in patients with diabetes. Since mitochondria are the primary target of Yang- and Qi-invigoration, the possible beneficial effects of Yang- and Qi-invigorating herbs in the prevention and/or treatment of diabetic cardiomyopathy and nephropathy warrant further investigation. The identification of active compounds isolated from Yang- and Qi-invigorating herbs and the elucidation of the biochemical mechanism(s) underlying their beneficial actions on mitochondrial function could not only provide a rational basis for developing herbal health products but also help to establish biomarkers for the quality control of Yang/Qi-invigorating herbal products.