Modified CFBP-bFGF targeting to ischemic brain promoted the functional recovery of cerebral ischemia

Modified bFGF targeting connective tissue growth factor in the injured microenvironment improved cardiac repair after chronic myocardial ischemia

Myocardial infarction (MI) was a cardiovascular emergency that led to heart failure, arrhythmia, and sudden death. Basic fibroblast growth factor (bFGF) was revealed to promote angiogenesis and protect cardiomyocytes against ischemic injury. But conventional delivery of bFGF in an uncontrolled manner was inefficient and diffusive, limiting its application in MI therapy. Currently, stimuli-responsive drug delivery is emphasized in tissue regeneration. The present study constructed a CFBP-bFGF recombinant protein, which could specifically target upregulated connective tissue growth factor (CTGF) and release bFGF in ischemic myocardium. In a rat model with MI, intravenous administration of CFBP-bFGF significantly accumulated in ischemic myocardium by targeting with CTGF. The responsive release of CFBP-bFGF effectively enhanced blood vessel regeneration, decreased cardiomyocyte apoptosis, and improved cardiac function recovery. In addition, the molecular mechanism was further explored by RNA sequencing and transcriptome analysis. Besides activating the pathways and genes related to angiogenesis and cardiac protection, CFBP-bFGF also decreased the expression of fibrosis-related pathways and genes, such as TGF-β. These results demonstrated that the CTGF-responsive CFBP-bFGF was effective for targeting release that promoted the functional recovery of MI.

A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

JOURNAL/nrgr/04.03/01300535-202502000-00028/figure1/v/2024-05-28T214302Z/r/image-tiff Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI (QK) are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases. However, conventional topical drug delivery often results in a burst release of the drug, leading to transient retention (inefficacy) and undesirable diffusion (toxicity) in vivo. Therefore, a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke. Matrix metalloproteinase-2 (MMP-2) is gradually upregulated after cerebral ischemia. Herein, vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG (TIMP) and customizable peptide amphiphilic (PA) molecules to construct nanofiber hydrogel PA-TIMP-QK. PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro. The results indicated that PA-TIMP-QK promoted neuronal survival, restored local blood circulation, reduced blood-brain barrier permeability, and restored motor function. These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

Modified EBP-bFGF targeting endogenous renal extracellular matrix protects against renal ischemia-reperfusion injury in rats

Acute kidney injury (AKI) is a life-threatening disease primarily caused by renal ischemia-reperfusion (I/R) injury, which can result in renal failure. Currently, growth factor therapy is considered a promising and effective approach for AKI treatment. Basic fibroblast growth factor (bFGF), an angiogenic factor with potent activity, efficiently stimulates angiogenesis and facilitates regeneration of renal tissue. However, the unrestricted diffusion of bFGF restricts its clinical application in AKI treatment. Therefore, developing a novel sustained released system for bFGF could enhance its potential in treating AKI. In this study, we genetically engineered a multifunctional recombinant protein by fusing bFGF with a specific peptide (EBP). EBP-bFGF effectively binds to the extracellular matrix in the injured kidney, enabling slow release of bFGF in AKI. Furthermore, following orthotopic injection into I/R rats' ischemic kidneys, EBP-bFGF exhibited stable retention within the tissue. Additionally, EBP-bFGF suppressed apoptosis of renal cells, reduced renal fibrosis, and facilitated recovery of renal function. These findings suggest that EBP-bFGF delivery system represents a promising strategy for treating AKI.

Comparative prototypes and metabolites of Du-zhi pill in normal and cerebral ischemia rats by UHPLC-Q-TOF-MS/MS method

Du-Zhi pill (DZP) is widely used as a Chinese medicine in treating cerebral ischemia. UHPLC-Q-TOF-MS/MS techniques were used to detect and identify the metabolites in rat brain samples of normal and middle cerebral artery occlusion (MCAO) model rats administered with DZP. It was tentatively found that 43 prototypes and 93 metabolites could be identified in rat brain samples. Normal and MCAO model rat brain samples contained 19 prototype components. Eight prototype components were only detected in normal rat brain samples, while 16 were found only in MCAO model rat brain samples. It was determined that 47 metabolites had been identified in the normal rats, while 86 had been placed in MCAO model rats. There were 40 common metabolites in both normal and MCAO model rat brain samples. Seven metabolites were only detected in normal rat brain samples, while 46 were found only in MCAO rat brain samples. The comparison of metabolites in brain samples of normal and MCAO rats showed apparent differences. It was discovered that glucuronidation, methylation, acetylation, and sulfation are phase II metabolic routes of DZP, while hydrogenation, hydroxylation, and dehydroxylation are phase I metabolic routes. Moreover, hydrogenation, glucuronidation, hydroxylation, and methylation were the main metabolic pathways because of the number of metabolites identified in these metabolic pathways. The results provide a valuable reference for further research into effective substances of DZP for treating cerebral ischemia.