Local Anesthetics, Antipsychotic Phenothiazines, and Cationic Surfactants Shut Down Intracellular Reactions through Membrane Perturbation in Yeast

Abstract

High osmolarity and glucose deprivation cause rapid shutdowns of both actin polarization and translation initiation in yeast. Like these stresses, administration of local anesthetics and of antipsychotic phenothiazines caused similar responses. All these drugs have amphiphilic structures and formed emulsions and permeabilized the cell membrane, indicating that they have the same features as a surfactant. Consistently with this, surfactants induced responses similar to those of local anesthetics and phenothiazines. Benzethonium chloride, a cationic surfactant, showed a more potent shutdown activity than phenothiazines, whereas SDS, an anionic surfactant, transiently depolarized actin without inhibiting translation initiation, suggesting that a cationic charge in the amphiphile is important to the shutdown of both reactions. The clinical drugs and the cationic surfactants at low concentrations caused shutdown without membrane permeabilization, suggesting that these compounds and stresses activate shutdown, via perturbation rather than disruption of the cell membrane.

Local Anesthetics and Antipsychotic Phenothiazines Interact Nonspecifically with Membranes and Inhibit Hexose Transporters in Yeast

“…Nonspecific intercalation of amphiphiles with membrane would inhibit this oscillation. However, in contrast to the effects caused by cationic TMA12, anionic SDS does not inhibit translation initiation (Uesono et al 2008), and additional glucose does not alleviate the SDS-associated growth inhibition ( Figure 3A). Therefore, anionic amphiphiles, which are considered to intercalate into outer leaflets (Deuticke 1968), are unlikely to induce glucose starvation.…”

“…Therefore, the addition of glucose or a glucose analogue effectively alleviates the responses induced by low drug concentrations, e.g., 2.5 mM TC. Actin polarization recovered to 80% in the budded cells, which was caused by omission of TC from the cells treated with 2.5 mM for 4 hr ( Figure 3C, left, black circle); this indicates that the effect of 2.5 mM TC is reversible, similar to the effects of low concentrations of cationic surfactant (Uesono et al 2008). In contrast, actin polarization recovered to just 27% after omission of TC from cells treated with 10 mM for 30 min ( Figure 3C, right, black circle), which shows that 10 mM is severely toxic.…”

“…In yeast, local anesthetics [e.g., tetracaine (TC), lidocaine (LC), dibucaine (DC), and procaine (PC)], antipsychotic phenothiazines [e.g., chlorpromazine (CPZ) and trifluoperazine (TFZ)], and a QAC [i.e., lauryltrimethylammonium compound (TMA12)] induce rapid and simultaneous inhibition of both translation initiation and actin polarization, responses that resemble those induced by high salinity and glucose starvation (Uesono et al 2008(Uesono et al , 2011. This response is unlikely to be caused by amino acid starvation inhibiting translation initiation without rapid depolarization of actin or by mild heat stress inhibiting actin polarization without translational inhibition (Delley and Hall 1999;Uesono and Toh-e 2002;Uesono et al 2004;Uesono 2009).…”

“…The destruction of membranes by surfactant activity accounts for the antibiotic-effect mechanism at high concentrations, but the antibiotic-effect mechanism at lower concentrations, where membranes are not destroyed, remains unknown (Wessels and Ingmer 2013). Structures of local anesthetics, phenothiazines, alcohols, and QACs are largely different, but they are all amphiphiles and thus, at high concentrations, have sufficient surfactant-like activity to lyse erythrocytes (Seeman 1972;Sheetz and Singer 1974), model membranes (Kitagawa et al 2004), and the budding yeast Saccharomyces cerevisiae (Uesono et al 2008(Uesono et al , 2011. This activity accounts for the common toxicity of these compounds at high concentrations.…”

“…This activity accounts for the common toxicity of these compounds at high concentrations. At low concentrations that do not cause cell lysis, these compounds induce similar responses, including the inhibition of both translation initiation and polarization of the actin cytoskeleton, nuclear localization of the stress-responsible transcription factor Msn2, and processingbody (P-body) formation for messenger RNA (mRNA) decay in a dose-dependent manner in yeast (Uesono et al 2008(Uesono et al , 2011Araki et al 2015). Volatile anesthetics (Bruce 1975;Heys et al 1989;Horber et al 1988), local anesthetics (Banerjee and Redman 1977;Wang et al 2011), and phenothiazines (Raghupathy et al 1970;Kumar et al 1991) are known to inhibit protein synthesis in animals at cellular, tissue, and whole-body levels.…”