Enhanced treatment for cerebral ischemia-reperfusion injury of puerarin loading liposomes through neutrophils-mediated targeted delivery

The recovery of blood circulation following cerebral infarction-associated thrombolysis brings new damage to the brain,which is cerebral ischemia-reperfusion injury(CIRI).Inflammation is the main pathological mechanism of CIRI.The inflammatory response triggered by cerebral ischemia-reperfusion provides neutrophils with a special opportunity to facilitate drug delivery to the site of ischemic penumbra through the chemotaxis of inflammatory factors by neutrophils.Puerarin is an isoflavone derivative with a significant neuroprotective effect in vitro.But the blood-brain barrier(BBB)impedes its therapeutic efficacy on CIRI within the brain.Inspired by the pathological process,we have used neutrophils as carriers to enhance the BBB penetration of liposomes loaded with puerarin and improve the concentration of puerarin in the brain parenchyma in this study.These results showed that puerarin-containing liposomes were released in response to inflammatory conditions associated with brain injury to enhance the neuroprotection effect at the ischemic penumbra.

A facile phototheranostic nanoplatform integrating NIR-Ⅱ fluorescence/PA bimodal imaging and image-guided surgery/PTT combinational therapy for improved antitumor efcacy

Phototheranostic with highly integrated functions is an attractive platform for cancer management. It remains challenging to develop a facile phototheranostic platform with complementary bimodal imaging and combinational therapy capacity. Herein, the small-molecule cyanine IR780 loaded liposomes have been harnessed as a nanoplatform to simultaneously realize photoacoustic(PA)/the second near-infrared window(NIR-Ⅱ) fluorescence imaging and image-guided surgery/adjuvant photothermal therapy(PTT).This nanoplatform exhibits attractive properties like uniform controllable size, stable dispersibility, NIR-Ⅱ fluorescence emission, photothermal conversion, and biocompatibility. Benefiting from the complementary PA/NIR-Ⅱ fluorescence bimodal imaging, this nanoplatform was successfully applied in precise vasculature delineation and tumor diagnosis. Interestingly, the tumor was clearly detected by NIR-Ⅱ fluorescence imaging with the highest tumor-to-normal-tissue ratio up to 12.69, while signal interference from the liver was significantly reduced, due to the difference in the elimination rate of the nanoplatform in the liver and tumor. Under the precise guidance of the image, the tumor was accurately resected, and the simulated residual lesion after surgery was completely ablated by adjuvant PTT. This combined therapy showed improved antitumor efcacy over the individual surgery or PTT. This work develops a facile phototheranostic nanoplatform with great significance in accurately diagnosing and effectively treating tumors using simple NIR light irradiation.