1. Brefeldin A reduces tumor necrosis factor-α-stimulated production of inflammatory mediators by suppressing the Akt, mTOR, and NF-κB pathways in human keratinocytes
Yoon Jeong Nam & Chung Soo Lee. Naunyn-Schmiedeberg's Arch Pharmacol
The lactone antibiotic brefeldin A has been shown to attenuate the secretion and production of chemical mediators involved in inflammation and immune responses (Hoermannsperger et al. 2009; Netschetal. 2006; Ouyang et al. 2013). Brefeldin A attenuates the TNF-α-inducedsecretionofcytokineIL-15inHeLacells (Ouyang et al. 2013). Brefeldin A inhibits the secretion and production of the T cell chemokine interferon-inducible protein (IP-10) in small intestinal epithelial cell line Mode-K cells treated with TNF-α (Hoermannsperger et al. 2009). Brefeldin A inhibits IL-1β-induced chemokine IL-8 secretion in the human epithelial colorectal adenocarcinoma cells Caco-2 (Netsch et al. 2006). Brefeldin A inhibits secretion of eosinophil cationic proteins from IFN-γ- and eotaxin-stimulated eosinophil granules (Neves et al. 2008). Brefeldin A has demonstrated to inhibit the PGE2-induced decrease in the production of chemokine (C-C motif) ligand 3 in Leishmania donovani (Saha et al. 2014). Brefeldin A inhibits the effect of Aralia cordate lectin on the expression and production of IL-8 in Caco-2 cells (Koyama et al. 2005). Brefeldin A suppresses the expression of IL-8 mRNA and production of IL-8 induced by Shiga toxin, ricin, and modeccin in Caco-2 cells (Yamasaki et al. 2004). Thus, brefeldin A appears to suppress production of chemical mediators involved in inflammation and immune responses.
2. Brefeldin A activates CHOP promoter at the AARE, ERSE and AP-1 elements
Simon C. M. Kwok, Ierachmiel Daskal. Mol Cell Biochem (2008) 319:203–208
The mediators of brefeldin A-induced apoptosis have not been well characterized. Evidence obtained so far indicates involvement of pRB dephosphorylation, p53-independent p21 activation, activation of caspase-3, caspase-7-mediated caspase-12 activation, activation of glycogen synthase kinase-3b and caspase-9, and activation of caspase-2, caspase-3, and caspase-9 via phosphorylation of c-Jun N-terminal kinase. We have studied the mechanism of action of brefeldin A using RT-PCR and promoter-luciferase reporter assay. We herein report that brefeldin A up-regulates CHOP expression via the activation of AARE1, ERSE, and AP-1 elements.
3. BIG1, a Brefeldin A-Inhibited Guanine Nucleotide-Exchange Factor, Is Required for GABA-Gated Cl-1 Influx Through Regulation of GABAA Receptor Trafficking
Cuixian Li & Shaorui Chen & Yang Yu & Chun Zhou & Ying Wang. Mol Neurobiol (2014) 49:808–819
In summary, the present work identifies an important role of BIG1 in the cell regulation of surface expression of GABAAR as well as a potential role for mediating synaptic inhibition by governing GABAAR intracellular trafficking. This novel function of BIG1 is dependent on its GEF activity. BIG2, another member of the brefeldin A-inhibited ARF-GEFs, has been reported to be a GABAAR β subunit-interacting protein. To further explore the involvement of BIG2 or the reciprocity of BIG1 and BIG2 in regulating GABAARs, trafficking in neurons will be investigated in future research.
4. The effect of brefeldin A on terbutaline-induced sodium absorption in fetal rat distal lung epithelium
Yasushi Ito, Naomi Niisato, Hugh O’Brodovich, Yoshinori Marunaka. Pflügers Arch – Eur J Physiol (1997) 434:492–494
Figure 1A shows the time course of changes in Isc after terbutaline (10 µM, a β2-specific adrenergic agonist) was added to the basolateral surface in the absence and presence of amiloride (10 µM) in the apical solution. Most of the terbutaline-induced Isc was sensitive to amiloride with a small component being sensitive to bumetanide. As shown in Figures 1A and B, terbuatline increased the amiloride-sensitive Isc about 2.5-fold at 50 min after its application. The effect of terbutaline was completely abolished when brefeldin A (1 µg/ml), an inhibitor of intracellular protein trafficking, had been added 30 minutes earlier into both the apical and basolateral solutions (total application time of brefeldin A = 80 min). Brefeldin A also decreased the amiloride-sensitive Isc of FDLE under basal conditions (Fig. 1B). In contrast to its effects on the amiloride-sensitive Isc, brefeldin A did not alter either the basal or terbutaline-stimulated bumetanide-sensitive Isc (Fig. 1C).