Lecithin nano-liposomal particle as a CRISPR/Cas9 complex delivery system for treating type 2 diabetes.

BACKGROUND: Protein-based Cas9 in vivo gene editing therapeutics have practical limitations owing to their instability and low efficacy. To overcome these obstacles and improve stability, we designed a nanocarrier primarily consisting of lecithin that can efficiently target liver disease and encapsulate complexes of Cas9 with a single-stranded guide RNA (sgRNA) ribonucleoprotein (Cas9-RNP) through polymer fusion self-assembly. RESULTS: In this study, we optimized an sgRNA sequence specifically for dipeptidyl peptidase-4 gene (DPP-4) to modulate the function of glucagon-like peptide 1. We then injected our nanocarrier Cas9-RNP complexes directly into type 2 diabetes mellitus (T2DM) db/db mice, which disrupted the expression of DPP-4 gene in T2DM mice with remarkable efficacy. The decline in DPP-4 enzyme activity was also accompanied by normalized blood glucose levels, insulin response, and reduced liver and kidney damage. These outcomes were found to be similar to those of sitagliptin, the current chemical DPP-4 inhibition therapy drug which requires recurrent doses. CONCLUSIONS: Our results demonstrate that a nano-liposomal carrier system with therapeutic Cas9-RNP has great potential as a platform to improve genomic editing therapies for human liver diseases.

Magnetic resonance imaging and acupuncture: a feasibility study on the migration of tracers after injection at acupoints of small animals.

OBJECTIVES: Acupuncture meridians in traditional Oriental medicine are known to be channels connecting specific points in the surface of the body to corresponding internal organs. We investigated the permeation and the transport of magnetic resonance imaging (MRI) contrast agent and tracer after injection at acupoints of small animals, such as rats and mice. METHODS: A geometric and systematic arrangement of acupuncture points on human skin surfaces has been depicted in traditional Oriental medicine, and the positions of the acupoints of small animals were determined by the application of a proportion on the animals corresponding to the morphological structures in humans. After injecting the materials at various acupoints, the agent migration behaviors inside the body were monitored by MRI. The distributions of the injected materials were reconstructed in 3-dimensional images for a more intuitive presentation. RESULTS: The widely-used gadolinium-compound contrast agent was not useful. Rather, a recently developed fluorine compound was effective for imaging the migration of the agent after injection into the acupoints BL18, 20, and 23. CONCLUSIONS: The final distributions of the agent from each injection point corresponded to the respective organs of the acupoints. The results suggested different migration paths and destinations for pharmacopuncture drugs.