Carbon Nanoparticles Inhibit Α-Glucosidase Activity and Induce a Hypoglycemic Effect in Diabetic Mice

New, improved therapies to reduce blood glucose are required for treating diabetes mellitus (DM). Here, we investigated the use of a new nanomaterial candidate for DM treatment, carbon nanoparticles (CNPs). CNPs were prepared by carbonization using a polysaccharide from Arctium lappa L. root as the carbon source. The chemical structure and morphology of the CNPs were characterized using Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, elemental analysis, and transmission electron microscopy. CNPs were spherical, 10-20 nm in size, consisting of C, H, O, and N, and featuring various functional groups, including C=O, C=C, C–O, and C–N. In vitro, the as-prepared CNPs could inhibit α-glucosidase with an IC(50) value of 0.5677 mg/mL, which is close to that of the reference drug acarbose. Moreover, in vivo hypoglycemic assays revealed that the CNPs significantly reduced fasting blood-glucose levels in mice with diabetes induced by high-fat diet and streptozocin, lowering blood glucose after intragastric administration for 42 days. To the best of our knowledge, this is the first report of CNPs exhibiting α-glucosidase inhibition and a hypoglycemic effect in diabetic mice. These findings suggest the therapeutic potential of CNPs for diabetes.