Resveratrol Inhibits Propagation ofChlamydia trachomatisin McCoy Cells

Abstract

Resveratrol (RESV), an antifungal compound from grapes and other plants, has a distinct ability to inhibit the Chlamydia (C.) trachomatis developmental cycle in McCoy cells, a classic cell line used for chlamydial research. Inoculation of C. trachomatis with increasing amounts of RESV (from 12.5 to 100 μM) gave a dose-dependent reduction in the number of infected McCoy cells visualized by using monoclonal antibodies against chlamydial lipopolysaccharide. A similar trend has been observed with immunoassay for major outer membrane protein (MOMP). Furthermore, there was a step-wise reduction in the number of C. trachomatis infective progenies caused by the increasing concentrations of RESV. The ability of RESV to arrest C. trachomatis growth in McCoy cells was confirmed by a nucleic acid amplification protocol which revealed dose-dependent changes in mRNAs for different genes of chlamydial developmental cycle (euo, incA, and omcB). Although the precise nature of the antichlamydial activity of RESV is yet to be determined and evaluated in future studies, the observed effect of RESV on C. trachomatis infection was not related to its potential effect on attachment/entry of the pathogen into eukaryotic cells or RESV toxicity to McCoy cells. Similar inhibitory effect was shown for C. pneumoniae and C. muridarum.

Resveratrol-Induced Xenophagy Promotes Intracellular Bacteria Clearance in Intestinal Epithelial Cells and Macrophages

“…However, to our knowledge, this is the first report describing induction of xenophagy by resveratrol. It has already been shown that resveratrol is able to restrict the number of intracellular Chlamydia trachomatis but the mechanism of action involved has not been identified (54). Besides, autophagy can restrict C. trachomatis survival suggesting that resveratrol might act on this cellular pathway to limit bacteria persistence in cells (55).…”

Chlamydia trachomatis Growth and Cytokine mRNA Response in a Prostate Cancer Cell Line

“…Moreover, there was a corresponding increase in infective progeny formation in CWR-R1 cells along with mRNA for EUO, a crucial gene controlling the early phase of the chlamydial development cycle. It remains an open question now if other developmental chlamydial genes ( incA and omcB ) studied in our previous work [15] have a different pattern of expression in McCoy and CWR-R1 cells during the later stages of infectious cycle. Interestingly, the changes in EUO expression between two cell lines studied were minimized and became statically insignificant at a later time point in the infectious cycle (48 hpi).…”

“…C. trachomatis was propagated in McCoy mouse fibroblasts grown in DMEM with 10% HyClone FCS supplemented with 2 mM glutamine, 4.0 mg/ml gentamicin, and 5.0 mg/ml amphotericin B, and further purified by Renografin gradient centrifugation, as previously described [15]. Briefly, elementary bodies were isolated and resuspended in sucrose-phosphate-glutamic acid (SPG) buffer (0.2 M sucrose, 8.6 mM Na2HPO4, 3.8 mM KH2PO4, 5 mM glutamic acid, 0.2 mm-filtered, pH 7.4).…”

“…RT-qPCR Taqman primers were designed using Primer 3 software and were validated by BLAST search and regression plot analysis using Cp values obtained with multiple dilutions of cDNA. Specificity of the designed primers and fluorescent probes was confirmed in different systems using cDNA from C. trachomatis Bu434, C. trachomatis UW-3/Cx, C. trachomatis UW- 31/Cx, and C. pneumoniae K-6, as well as from uninfected McCoy and CWR-R1 cells and some other common bacterial pathogens as previously described [15].…”

“…Primers for human fibroblast growth factor-2 (FGF-2) were: PR-F 5′-GGCTTCTTCCTGCGCATCCA-3′ and PR-R 5′-GCTCTTAGCAGACATTGGAAGA-3′. Primer sequences for eukaryotic beta-actin were used as published previously [15, 16]. All primers were verified and used at 0.4 µ M final concentration under thermal cycling conditions of 95°C for 10 min, 50 cycles of 95°C for 15 seconds, 60°C for 1 min, and 72°C for 20 seconds.…”