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Patai, R.

Publications and source records attributed to Patai, R..

2 recordsLinked to original sources

Rejuvenation of the Aged Cerebrovascular System via Protein Corona-Guided Fusogenic Liposome Delivery

Brain vascular aging is increasingly recognized as a critical therapeutic target for age-related cognitive decline. Oxidative stress, bioenergetic dysfunction, and molecular damage play central roles in the progression of vascular aging, contributing to cerebrovascular dysfunction and impaired cognitive function. While naturally occurring polyphenols such as resveratrol (RSV) have demonstrated potential in mitigating aging-related pathologies, their poor bioavailability and limited brain targeting efficiency significantly constrain their therapeutic impact. As a result, high doses or advanced drug delivery strategies are necessary to achieve meaningful physiological effects. We introduce a novel nanocarrier system designed to enhance RSV delivery to the cerebral endothelium by leveraging the natural formation of an apolipoprotein E (ApoE)-enriched protein corona around fusogenic liposomes (FL) in vivo. These nanoparticles directly fuse with cytoplasmic cell membranes and thus evade endocytosis. We found that once in the circulation FL spontaneously acquire a protein corona, which is highly enriched in ApoE, a key ligand for brain endothelial low-density lipoprotein receptors (LDLR). Based on this observation, we engineered an ApoE-functionalized protein corona around FL (ApoE-FL) to systematically evaluate whether this mechanism could be exploited for targeted brain delivery. Following optimization and physicochemical characterization, the RSV-loaded liposomes were evaluated in vitro using human cerebral microvascular endothelial cells and in vivo C57BL/6 aged mice to assess their therapeutic potential. Both FL and engineered ApoE-FL liposomal delivery systems exhibited a strong affinity for endothelial cell membranes in vitro. The knockdown of the ApoE receptor, low-density lipoprotein receptor-related protein 1 (LRP1), significantly reduced liposomal docking. Microscopy analysis revealed that both ApoE-FL and non-functionalized FL directly fused with endothelial plasma membranes, thus bypassing intracellular organelles and minimizing lysosomal degradation. This suggests that the naturally formed ApoE corona in vivo may contribute to efficient cerebrovascular targeting, a property successfully replicated by the engineered ApoE corona strategy. In vivo biodistribution and kinetic studies demonstrated that especially ApoE-FL achieved enhanced brain-targeting efficiency, prolonged cerebrovascular retention, and extended targeting distance along the arteriovenous axis. This emphasizes that fusogenic liposomes effectively engage almost the entire microvascular network, including capillaries and post-capillary venules. Functionally, fusogenic liposome-delivered RSV improved blood-brain barrier (BBB) integrity, enhanced neurovascular coupling (NVC) responses, and promoted brain vascularization in aged mice. Single-cell RNA sequencing (scRNA-seq) revealed enhanced endothelial angiogenesis and barrier protective transcriptional profiles in cerebrovascular cells treated with ApoE-FL/RSV, suggesting a molecular basis for the observed vascular benefits. Liposomal RSV delivery achieved near-complete cerebrovascular and cognitive rejuvenation in aged mice applying a 2000-fold lower RSV dose than oral administration used as control sample. Thus, ApoE-FL liposomes exhibited exceptionally high delivery efficiency in deeper brain regions, further expanding their therapeutic potential. These findings underscore the importance of targeted drug delivery in optimizing therapeutic outcomes and establish ApoE-functionalized fusogenic liposomes as a promising strategy for mitigating brain vascular aging and cognitive decline. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=103 SRC="FIGDIR/small/709925v1_ufig1.gif" ALT="Figure 1000"> View larger version (52K): org.highwire.dtl.DTLVardef@acad5borg.highwire.dtl.DTLVardef@a96e3borg.highwire.dtl.DTLVardef@18405aeorg.highwire.dtl.DTLVardef@90e349_HPS_FORMAT_FIGEXP M_FIG C_FIG

animal behavior and cognition↗

CotH genes are necessary for normal spore formation and virulence in Mucor lusitanicus

Mucormycosis is an invasive fungal infection caused by certain members of the fungal order of Mucorales. The species most frequently identified as the etiological agents of mucormycosis belong to the genera Rhizopus, Lichtheimia and Mucor. The frequency of systemic mucormycosis has been increasing, mainly because of the elevating numbers of susceptible patients. Furthermore, Mucorales display intrinsic resistance to the majority of routinely used antifungal agents (e.g., echinocandins and short-tailed azoles), which limits the number of possible therapeutic options. All the above-mentioned issues urge the improvement of molecular identification methods and the discovery of new antifungal targets and strategies. Spore coat proteins (CotH) constitute a kinase family present in many pathogenic bacteria and fungi and participate in the spore formation in these organisms. Moreover, some of them can act as virulence factors being receptors of the human GRP78 protein during Rhizopus delemar-induced mucormycosis. We identified 17 cotH-like genes in the Mucor lusitanicus genome database. Successful disruption of five cotH genes was performed using the CRISPR-Cas9 system in Mucor. The CotH3 and CotH4 proteins play a role in adaptation to different temperatures as well as in developing the cell wall structure. We also show CotH4 protein is involved in spore wall formation by affecting the total chitin content and thus, the composition of the spore wall. Furthermore, we demonstrate that spore size is dependent on the cotH4 gene. The role of CotH3 and CotH4 proteins in virulence was confirmed in two invertebrate models and DKA mouse model. IMPORTANCECurrent treatment options for mucormycosis are inadequate resulting in high mortality rates especially among immunosuppressed patients. The development of novel therapies for mucormycosis has been hampered by lack of understanding of the pathogenetic mechanisms. The importance of the cell surface CotH proteins in the pathogenesis of Rhizopus-mediated mucormycosis has been recently described. However, the contribution of this family of proteins to the virulence of other mucoralean fungi and their functionality in vital processes remain undefined. Through the use of CRISPR-Case9 gene disruption system, we demonstrate the importance of several of the CotH proteins to the virulence of Mucor lusitanicus by using three infection models. We also report on the importance of one of these proteins, CotH4, to the spore wall formation through affecting the chitin content. Therefore, our studies extend the importance of CotH proteins to Mucor and identifies the mechanism by which one of the CotH proteins contributes to the development of a normal fungal cell wall, thereby indicating that this family of proteins can be targeted for future development of novel therapeutic strategies of mucormycosis.

microbiology↗