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This study was conducted to determine the capacity of the asialoglycoprotein receptor on the hepatocyte-derived cell line HepG2 to exhibit an anomeric preference with respect to the D-galacto moiety on cationic liposome membrane-anchored cholesteryl-α-D-galactopyranoside (Choαgal) and cholesteryl-β-Dgalactopyranoside (Cholβgal) in cationic liposome/pGL3 plasmid DNA complexes constructed for non-viral, hepatocyte-directed gene transfer. In addition, cholesteryl-α-D-glucopyranoside (Choαglu) and cholesteryl-β-D-glucopyranoside (Cholβglu) were separately formulated into cationic liposomes at the same mole ratio (11%) to examine the C-4 epimeric selectivity of the asialoglycoprotein lectin for the glucopyranosides displayed in derived lipoplexes. Lipoplex formation was examined by gel retardation, ethidium displacement assays, and transmission electron microscopy. Plasmid DNA was shown to be fully liposome associated and maximally compacted at a liposome:DNA ratio of 6:1 (weight ratio), corresponding to a +/- charge ratio of 1.3 with complexes falling in the 80–200 nm size range, whereas at a 5:1 w/wratio [1.1 (+/-) charge ratio] lipoplexes were somewhat smaller (50–100 nm) but promoted higher transgene activity in HepG2 cells than 6:1 (w/w) lipoplexes, in the following order: Cholβgal > Cholαgal > Cholβglu = Cholαglu. Transgene activity levels in HeLa cells which lack the asialoglycoprotein receptor were approximately 10% of those achieved in HepG2 cells. Moreover, transgene activity in HepG2 cells was reduced by approximately 90% in the presence of excess asialofetuin, a ligand for the asialoglycoprotein lectin. [ABSTRACT FROM AUTHOR]

Introduction: Vascular contributions to cognitive impairment and dementia (VCID) are a leading cause of dementia. An underappreciated, modifiable risk factor for VCID is hyperhomocysteinemia (HHcy), defined by elevated levels of plasma homocysteine, most often due to impaired B vitamin absorption in aged persons. Studies aimed at identifying neuropathologic features and gene expression profiles associated with HHcy have been lacking., Methods: A subset of research volunteers from the University of Kentucky Alzheimer's Disease Research Center longitudinal cohort came to autopsy and had ante mortem plasma homocysteine levels available. Brain tissue and blood plasma drawn closest to death were used to measure homocysteine and related metabolites in the current pilot study. Genetic expression profiles of inflammatory markers were evaluated using the Human Neuroinflammation NanoString panel. Further analyses included an evaluation of plasma homocysteine effects on amyloid beta, tau, ionized calcium-binding adaptor molecule 1, and glial fibrillary acidic protein immunohistochemistry in the frontal and occipital cortices. Analytes and other study outcomes were evaluated in relation to ante mortem HHcy status: We identified 13 persons with normal ante mortem plasma homocysteine levels (<14 µmol/L) and 18 who had high plasma homocysteine levels (≥14 µmol/L)., Results: Participants with HHcy demonstrated increased levels of several plasma homocysteine cycle metabolites such as total cysteine, S-adenosyl-homocysteine, cystathionine, and choline. Inflammatory gene expression profiles showed a general downregulation in the setting of elevated plasma homocysteine. HHcy was associated with more and longer microglial processes, but smaller and fewer astrocytes, especially in participants of older age at death. HHcy in older participants was also associated with occipital cortex microhemorrhages and increased severity of atherosclerosis throughout the cerebral vasculature., Conclusions: Increased plasma homocysteine and older age were associated with the downregulation of inflammatory gene expression markers in association with significant glial and vascular pathology changes. Impaired immune function is a plausible mechanism by which HHcy increases cerebrovascular damage leading to impaired cognitive function., Competing Interests: The authors declare they have no conflicts of interest. Author disclosures are available in the supporting information., (© 2022 The Authors. Alzheimer's & Dementia: Translational Research & Clinical Interventions published by Wiley Periodicals LLC on behalf of Alzheimer's Association.)