Cranberry and Grape Juices Affect Tight Junction Function and Structural Integrity of Rotavirus-Infected Monkey Kidney Epithelial Cell Monolayers

Abstract

Cranberry juice (CJ) and grape juice (GJ) from Vaccinium macrocarpon and Vitis labrusca, respectively, and purified proanthocyanidins (PACs) from these species are recognized to possess antiviral activity. The effects of CJ and GJ on tight junction (TJ) structure and function among rotavirus-infected monkey kidney epithelial cells in monolayer cultures were evaluated. Antiviral activity by cranberry PACs of rotavirus in cell-free suspension was investigated by a rotavirus antigen [i.e., viral capsid protein 6 (VP6)] capture enzyme-linked immunosorbent assay (ELISA) and by transmission electron microscopy (TEM). MA-104 monolayers were treated with CJ, GJ, or cranberry juice cocktail (CJC) drink before inoculation with rotavirus. TJ function and structural integrity were measured by changes in transepithelial electrical resistance (TEER) and by reduction of signal intensity of the TJ a-claudin 1 by immunofluorescence. The inhibitory activity of CJ and GJ on viral RNA synthesis, as a function of viral concentration, was determined by reverse transcription polymerase chain reaction (rtPCR). After 4 days, virus-infected monolayers pretreated with GJ (Concord and Niagara GJs) had TEER readings similar to uninfected controls. CJ and CJC also had a significant protective effect (P \ 0.05) on TJ function, but to a lesser extent than GJ. Disorganization of TJ integrity commenced at 24-to 36-h post-viral inoculation, but this effect was reduced by pretreatment with CJ or GP of monolayer cultures. TEM showed aggregation of rotavirus by cranberry PACs. The destruction of rotavirus capsid proteins VP6, in cell-free suspension was inversely related to the concentration of cranberry PACs (C-PAC). Loss of rotavirus RNA by CJ or GJ was inversely related to viral infectivity titers. CJ, GJ, or PAC-associated antiviral activity has been linked to modifications in cellular physiologic events and to physical factors (e.g., PAC-mediated viral aggregation) that probably compromise viral infectivity. Multiple cell physiological and physical events must be considered when determining the mechanisms associated with the antiviral (i.e., rotavirus) activity of CJ, GJ, and PACs.

Perturbation of Host Cell Cytoskeleton by Cranberry Proanthocyanidins and Their Effect on Enteric Infections

“…In addition to PAC, flavonoid compounds include anthocyanins, flavonols and catechins and are often collectively referred to as “extracts” [5] . At certain concentrations, cranberry flavonoids have been attributed antiviral properties [6] , [7] as well as antimicrobial properties against many important human pathogens, including Escherichia coli , Helicobacter pylori , Listeria monocytogenes , Porphyromonas gingivalis , Salmonella Typhimurium, and Staphylococcus aureus [8] , [9] , [10] , [11] , [12] , [13] . In addition to these observed antiviral and antibacterial properties, cranberry flavonoids also exhibit effects directly on mammalian cells.…”

Comparison of α-glucosyl hesperidin of citrus fruits and epigallocatechin gallate of green tea on the Loss of Rotavirus Infectivity in Cell Culture

“…It would not be unreasonable to suggest a flavonoid mediated direct affect on RTV VP6 capsid protein and in turn, a blockage of the particle’s antigenic determinants’ binding to the EIA capture antibody. Supportive to this suggestion is our recent work using transmission electron microscopy, showing an enshrouding or total entrapment of RTV by soluble and particulate proanthocyanidins ( Lipson et al, 2011 , 2012 ). As similarly recognized among the proanthocyanidin group of flavonoids, hesperidin and its aglycone hesperitin function in part, as protein adsorbents, supporting our proposed mechanism of GH-associated RTV capsid antigen loss of activity (see the works by Ding et al, 2012 ; Chakraborty et al, 2013 ; Shen and Lu, 2013 ).…”

“…All testing was performed in triplicate. Developed in the 1980s, the rotavirus antigen capture EIA, has since been used as a sensitive and specific system by medical laboratory personnel and infectious disease specialists for the monitoring of viral antigen as well as RTV (Type A) clinical disease, respectively, ( Cukor et al, 1984 ; Stals et al, 1984 ; Knowlton et al, 1991 ; Dornai et al, 1993 ; Raj et al, 2007 ; Fang et al, 2009 ; Tran et al, 2010 ; Lipson et al, 2011 ; Gautam et al, 2013 ; Sai et al, 2013 ; Lipson, Personal observation). The RTV antigen capture EIA, as well as most other antigen/antibody capture EAI systems, may readily be exploited in a quantitative manner as performed in the current study (see EDVOTEK, 2011 ).…”

Effect of a Δ9-tetrahydrocannabinol (THC)/cannabidiol (CBD) formulation on cell monolayer viability and mitochondria integrity: Significance of the drug carrier/delivery system

“…After 24 and 48-h, monolayers were dispersed by trypsinization and fi xed in 3% glutaraldehyde with 1% sodium cacodylate. The cells were dehydrated in ethanol, embedded en bloc, sectioned, and mounted on grids for examination using a Hatachi transmission electron microscope [10,11]. The negative control was treated as the experimental, but methanol was added to the MM instead of the CBD.…”