Shells of compacted DNA as nanocontainers transporting proteins in multiplexed delivery

A Facile and Versatile Platform for Cytosolic Delivery of Proteins in Nanoshells of DNA or RNA: Packaging Options in Multiplexed Delivery

Polyethylenimine (PEI) polymers are used to compact DNA into nanoparticles for delivery into cells. We have shown that PEI-mannose polymers compact DNA into nanoshell-like particles, which can load proteins as well. Here we show that these DNA containers are uniquely versatile for scavenging proteins, irrespective of size, charge, and hydrophobicity from dilute solutions. The number of DNA containers for loading proteins can be controlled independently of the protein loading per container by changing the amounts of DNA and protein in solution. This provides control of the fraction of cells receiving the payload and the relative amounts of DNA and protein per cell. The proteins released inside cells retain enzymatic activity. The proposed technology provides a new way to approach protein delivery by hitchhiking proteins within a facile and well-established DNA-delivery mechanism and by utilizing sugar biophysics to load a wide range of proteins in a single-step process.

Nerve growth factor loaded hypotonic eye drops for corneal nerve repair

Neurotrophic keratopathy is a degenerative disease caused by corneal nerve damage, leading to corneal ulceration. Recombinant human nerve growth factor (rhNGF) was approved for neurotrophic keratitis therapy; however, the excipients of the eye drops are not optimized for its controlled release. To this aim, we introduce the hypotonic hydrogel PF127 as an excipient for rhNGF in eye drops. We confirmed the formation of a hydrogel using a vial-inversion test and based on rheological properties. The hydrogel exerts shear-thinning behavior upon sweep test with a favorable transmittance and a natural refractive index. Moreover, the hydrogel exhibited fast and sustained rhNGF release kinetic, along with constant dissolution and the formation of a network-like structure. The release of rhNGF was confirmed by the proliferation of PC12 cells and its protective effect on damaged axons of dorsal root ganglia cells. The hydrogel performed accordingly in the in-situ ocular gelation and ocular surface retention test. We further confirmed that labeled proteins were released from the hydrogel to the cornea. Preclinical testing in mice showed that rhNGF hydrogels supported the recovery from corneal epithelial defects: they reduced the defect size and increased corneal nerve density. Schirmer's test revealed improved corneal nerve function based on tear secretion. The hydrogel resists clearance from blinking and enhances the intraocular absorption of rhNGF. The ocular surface, retinal thickness, and the ciliary body and retina remained unchanged. Together, these findings suggest that the hypotonic PF127 hydrogel is a suitable rhNGF delivery system to prepare eye drops for potential use in neurotrophic keratopathy.

Disinfection Byproducts of Haloacetaldehydes Disrupt Hepatic Lipid Metabolism and Induce Lipotoxicity in High-Fat Culture Conditions

Unhealthy lifestyles, obesity, and environmental pollutants are strongly correlated with the development of nonalcoholic fatty liver disease (NAFLD). Haloacetaldehyde-associated disinfection byproducts (HAL-DBPs) at various multiples of concentrations found in finished drinking water together with high-fat (HF) were examined to gauge their mixed effects on hepatic lipid metabolism. Using new alternative methods (NAMs), studying effects in human cells in vitro for risk assessment, we investigated the combined effects of HF and HAL-DBPs on hepatic lipid metabolism and lipotoxicity in immortalized LO-2 human hepatocytes. Coexposure of HAL-DBPs at various multiples of environmental exposure levels with HF increased the levels of triglycerides, interfered with de novo lipogenesis, enhanced fatty acid oxidation, and inhibited the secretion of very low-density lipoproteins. Lipid accumulation caused by the coexposure of HAL-DBPs and HF also resulted in more severe lipotoxicity in these cells. Our results using an in vitro NAM-based method provide novel insights into metabolic reprogramming in hepatocytes due to coexposure of HF and HAL-DBPs and strongly suggest that the risk of NAFLD in sensitive populations due to HAL-DBPs and poor lifestyle deserves further investigation both with laboratory and epidemiological tools. We also discuss how results from our studies could be used in health risk assessments for HAL-DBPs.

Self-assembly CuO-loaded nanocomposite involving functionalized DNA with dihydromyricetin for water-based efficient and controllable antibacterial action

With the antibiotic crisis intensifies, the defense and treatment of pathogen infections in safe and effective fashion has become a critical issue. Herein, we report a novel and advanced type of sterilization agent designed via the functionalization DNA nanocarriers based on dihydromyricetin and CuO-loaded nanoparticles (DNA/DMY-CuO). Firstly, a pure dihydromyricetin (DMY) isolated from Ampelopsis grossedentata is used as a bridge to the stimulate the construction of DNA cross-linking networks by hydrogen bonding. Subsequently, a 3D spherical CuO-loaded nanocomposite (204.39 nm) is customized using the DNA/DMY network as a biological template through a simple coordination-assisted self-assembly method, which exhibits a high dispersibility, water-solubility and physiological stability. The reversible physical interactions in nanocarriers allows the selective separation and automatic release of CuO NPs from DNA/DMY-CuO in neutral and wound exudate environments, thereby extending the survival period of CuO NPs by nearly 24 h. Meanwhile, the nanocarriers system relied on the strong binding ability of DMY to the outer membrane of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) achieves controlled drug delivery onto the pathogen wall. The advanced antibacterial action of DNA/DMY-CuO also reflected in membrane destruction, cytoplasmic constituent leakages and ATP synthetic pathway cessation, thereby halting cytosolic metalloregulatory mechanisms and minimizing drug-resistant bacteria. In summary, such multi-functional CuO-loaded nanocomposite provides a water-dispersibility, controllable, low cytotoxicity and long-effective platform to address the ever-growing threats of bacterial infections.