Treatment of Acute Kidney Injury Using a Dual Enzyme Embedded Metal-organic Framework-mediated Cascade That Catalyzes in Vivo ROS Scavenging

Background: Significant advances have been made in recent years to utilize natural enzymes with antioxidant properties for the treatment of acute kidney injury (AKI). However, these enzymes have limited clinical utility due to their limited cellular uptake, poor pharmacokinetic properties, and suboptimal stability. We prepared a novel biomimetic mineralization approach to overcome these limitations.Results: Catalase (CAT) and superoxide dismutase (SOD) were encapsulated in a zeolitic imidazolate framework-8 (ZIF-8), then this SOD@CAT@ZIF-8 complex was anchored with MPEG2000-COOH to yield an MPEG2000-SOD@CAT@ZIF-8 (PSCZ) composite. This composite was then utilized as a stable tool with antioxidant properties for the integrated cascade-based treatment of AKI, remarkably improved intracellular enzyme delivery. The PSCZ composite showed a significantly relieve ability of H2O2 induced ROS and prevented apoptosis in HEK293 cells. In vivo, this composite showed a protective effect in the cisplatin-induced AKI mouse model. In addition, PSCZ treatment mitigated renal dysfunction and histological injury, like tubulointerstitial infiltration. RNA sequencing results further confirmed the protective effect of PSCZ and the potential molecular mechanism was revealed. PSCZ treatment reduced renal inflammation and inflammatory gene expression and ameliorated increased apoptosis and inflammatory infiltration of renal tubules. Moreover, PSCZ administration regulated renal injury via the p53 signaling pathway. These renoprotective effects of PSCZ treatment were more potent in CP-AKI mice than those of SOD or CAT alone. This dual-enzyme-embedded metal-organic framework was able to scavenge reactive oxygen species synergistically and effectively. Conclusion: PSCZ can remarkably improve intracellular enzyme delivery, and it can be used as a stable tool with antioxidant properties for the integrated cascade-based treatment of AKI. The ZIF-8-based “armor plating” represents an effective means of shielding enzymes with improved therapeutic utility to guide the precision medicine-based treatment of AKI.

Decreased Wait Time and Increased Satisfaction With Bedside Pancreatic Enzyme Dosing for the Inpatient Adolescent With Cystic Fibrosis: A Quality Improvement Project Comparing Enzyme Self-Administration to Nurse Administration

For children with cystic fibrosis (CF), enzymes are essential with meals to absorb nutrients and ensure adequate growth. When hospitalized, CF patients typically rely on nurse-administered medications. Recently, a pediatric hospital unit began allowing adolescents with CF enzymes at the bedside. Postimplementation, a satisfaction questionnaire was administered to participating patients and nurses measuring patient and nurse satisfaction with access to bedside enzymes versus nurse administration and overall time for enzyme delivery. The survey utilized a 5-point Likert scale. The wait time for pancreatic enzymes decreased for self-administered enzymes when compared to those that were nurse administered. All (11/11) patients and 86% (12/14) of nurses preferred the self-administration of enzymes. Hospitalized pediatric CF patients and nurses had higher levels of satisfaction with enzyme self-administration. Immediate access to enzymes in room safes impact patient autonomy, reflecting home self-care practices. Decreases in wait times optimize nutritional growth and healing while hospitalized. As a result, a new limited scope policy allowing patient-administered enzymes is now in place in the pediatric inpatient CF unit.

A DNA-mediated crosslinking strategy to enhance cellular delivery and sensor performance of protein spherical nucleic acids

By crosslinking protein spherical nucleic acid (SNA) into a supramolecular architecture X-SNA, the intracellular enzyme delivery efficiency was significantly enhanced, showing 3–4 times higher signal-to-noise ratio in detecting intracellular lactate.

Rapid Clathrin-Mediated Uptake of Recombinant α-Gal-A to Lysosome Activates Autophagy

Enzyme replacement therapy (ERT) with recombinant alpha-galactosidase A (rh-α-Gal A) is the standard treatment for Fabry disease (FD). ERT has shown a significant impact on patients; however, there is still morbidity and mortality in FD, resulting in progressive cardiac, renal, and cerebrovascular pathology. The main pathway for delivery of rh-α-Gal A to lysosome is cation-independent mannose-6-phosphate receptor (CI-M6PR) endocytosis, also known as insulin-like growth factor 2 receptor (IGF2R) endocytosis. This study aims to investigate the mechanisms of uptake of rh-α-Gal-A in different cell types, with the exploration of clathrin-dependent and caveolin assisted receptor-mediated endocytosis and the dynamics of autophagy-lysosomal functions. rh-α-Gal-A uptake was evaluated in primary fibroblasts, urine originated kidney epithelial cells, and peripheral blood mononuclear cells derived from Fabry patients and healthy controls, and in cell lines HEK293, HTP1, and HUVEC. Uptake of rh-α-Gal-A was more efficient in the cells with the lowest endogenous enzyme activity. Chloroquine and monensin significantly blocked the uptake of rh-α-Gal-A, indicating that the clathrin-mediated endocytosis is involved in recombinant enzyme delivery. Alternative caveolae-mediated endocytosis coexists with clathrin-mediated endocytosis. However, clathrin-dependent endocytosis is a dominant mechanism for enzyme uptake in all cell lines. These results show that the uptake of rh-α-Gal-A occurs rapidly and activates the autophagy-lysosomal pathway.