Coronaviruses (CoVs) are important human pathogens for which no specific treatment is available. Here, we provide evidence that pharmacological reprogramming of ER stress pathways can be exploited to suppress CoV replication. The ER stress inducer thapsigargin efficiently inhibits coronavirus (HCoV-229E, MERS-CoV, SARS-CoV-2) replication in different cell types including primary differentiated human bronchial epithelial cells, (partially) reverses the virus-induced translational shut-down, improves viability of infected cells and counteracts the CoV-mediated downregulation of IRE1α and the ER chaperone BiP. Proteome-wide analyses revealed specific pathways, protein networks and components that likely mediate the thapsigargin-induced antiviral state, including essential (HERPUD1) or novel (UBA6 and ZNF622) factors of ER quality control, and ER-associated protein degradation complexes. Additionally, thapsigargin blocks the CoV-induced selective autophagic flux involving p62/SQSTM1. The data show that thapsigargin hits several central mechanisms required for CoV replication, suggesting that this compound (or derivatives thereof) may be developed into broad-spectrum anti-CoV drugs.

u. I. Elmadfa, Reduzierung d e r Lipidperoxidation in Forellenfilet durch Supplementierung des Futters mit Vitamin E, Erniihrungsumschau 41, (3) 116 [1994]. H. Schdfer u . I. Elmadfa, Die Wirkung nicht verseifbarer Nahrungsfettkomponenten auf die Lipidperoxidation in Abhlngigkeit des Fettsluremusters, Fette Seifen . Anstrichmittel 85, H. Schdfer u. I. Elmadfa, EinfluB verschiedener Lagerungstemperaturen u n d Lagerungszeiten auf die Peroxidbildung in Fut-563-566 [ 19831. terproben bei Zusatz von a-o d e r y-Tocopherol, Tierphysiol. Tierernahr., Futtermittelkunde 51 (4). 229 -236 [1984]. A. Kornfefd and L. E. Croon, 4-Dimethyl-4-monomethyl and 4,4-dimethylsterols in some vegetable oils, Lipids 16, 306-314 [1981]. B. Schmirr, N . Both u. 1. Elmadfa, Der EinfluB unverseifbarer Nahrungskomponenten auf d a s Plasmacholesterin d e r Ratte bei cholesterinarmer Diat in Abhangigkeit vom FettsPuremuster, Fette . Seifen . Anstrichmittel 85,577-581 [1983].Eingegangen a m 23. Januar 1995.Tocopherole -Antioxidantien der Natur * G . P o n g r a c z , H . W e i s e r u n d D . M a t z i n g e r ** E Hoffmann-La Roche AG, Basel, SchweizDie Tocopherole sind biologisch wirksame Naturstoffe. Sie sind sowohl in vivo als auch in vitro wirksam. Vitamin E ist das wichtigste fettlosliche Antioxidans in den Zellmembranen, aber ebenso auch in den pflanzlichen blen. Die Gemeinsamkeiten resp. Unterschiede in der Wirkung in vivo und in vitro werden bei folgenden Tocopherolen diskutiert:-Tocopherol- Homologe: a-, 8-, y-. &Tocopherol (TL); hachste Vitamin-E-Wirkung a-TL; beste Antioxidans (A0)-Wirkung in vitro y-TL. -Tocotrienole ('IT): Hachste Vitamin-E-Wirkung a-TT (30% von a-TL); beste AO-Wirkung y -n . a-Tocopherol-Stereoisomere: RRR-, RRS-, RSS-, SSS-, RSR-, SRS-, SRR-, SSR-a-TL. AktivitBtsbereich: In abnehmender Reihenfolge von 1.0 bis 0.21; AO-Wirkung in vitro: Alle 8 Stereoisomere sind identisch. AktivitPtsverhBltnis all-rac-: RRR-a-TL-Acetat-. 1:1.36. -Iso-a-Tocopherol (2-Phyty1, 2-methy1, 5,6,7-trimethyl, 8-chromanol): Keine in vivo-Wirkung im Oxydationsmittel induzierten HPmolysetest; linear ansteigende AO-Wirkung in Speisefetten ohne pro-oxidative Wirkung in haheren Konzentrationen.

According to the USP, 2R,4'R,8'R-alpha-tocopheryl acetate (RRR-alpha-TAc) is 1.36 times more active than all-rac-alpha-tocopheryl acetate (all-rac-alpha-TAc). The all-rac form contains 12.5% each of the stereoisomers RRR, RRS, RSR, RSS, SSS, SSR, SRS and SRR, which display different biopotencies. In the present study, female rats fed a vitamin E-deficient diet were administered 0.82 mg of all-rac-alpha-TAc or 0.60 mg of RRR-alpha-TAc daily for up to 90 d. alpha-Tocopherol concentrations in liver, brain, adipose tissue and plasma were not significantly different among groups on treatment d 64 and 90. Thus, equipotent dosages of all-rac-alpha-TAc or RRR-alpha-TAc resulted in equimolar alpha-tocopherol plasma and tissue concentrations. A comparison with rats administered tocopherol-free placebo showed that plasma and tissue alpha-tocopherol of alpha-TAc-treated rats represented alpha-tocopherol uptake during the repletion period. The eight individual alpha-tocopherol stereoisomers in tissues and plasma were determined by chiral HPLC and capillary gas chromatography. Rats treated with all-rac-alpha-TAc preferentially accumulated the four 2R alpha-tocopherol stereoisomers (15-22% each, sum of all 2R = 70-86%) in tissues and plasma. The remaining 14-30% were 2S stereoisomers with a predominance of the SRS form. In conclusion, all-rac-alpha-TAc administration led to the presence of all eight alpha-tocopherol stereoisomers in rat liver, brain, adipose tissue and plasma. The four 2R stereoisomers including RRR-alpha-tocopherol were equally and significantly enriched. This confirmed that the configuration at C-2 of the alpha-tocopherol molecule has a major impact on stereoisomer biodiscrimination. Furthermore, the results are in agreement with the hypothesis that for alpha-tocopherol stereoisomers, biopotency differences are related to corresponding differences of alpha-tocopherol concentrations.

Signals and posttranslational modifications regulating the decapping step in mRNA degradation pathways are poorly defined. In this study we reveal the importance of K63-linked ubiquitylation for the assembly of decapping factors, P-body formation, and constitutive decay of instable mRNAs encoding mediators of inflammation by various experimental approaches. K63-branched ubiquitin chains also regulate IL-1-inducible phosphorylation of the P-body component DCP1a. The E3 ligase TRAF6 binds to DCP1a and indirectly regulates DCP1a phosphorylation, expression of decapping factors, and gene-specific mRNA decay. Mutation of six C-terminal lysines of DCP1a suppresses decapping activity and impairs the interaction with the mRNA decay factors DCP2, EDC4, and XRN1, but not EDC3, thus remodeling P-body architecture. The usage of ubiquitin chains for the proper assembly and function of the decay-competent mammalian decapping complex suggests an additional layer of control to allow a coordinated function of decapping activities and mRNA metabolism in higher eukaryotes.

How cytokine‐driven changes in chromatin topology are converted into gene regulatory circuits during inflammation still remains unclear. Here, we show that interleukin (IL)‐1α induces acute and widespread changes in chromatin accessibility via the TAK1 kinase and NF‐κB at regions that are highly enriched for inflammatory disease‐relevant SNPs. Two enhancers in the extended chemokine locus on human chromosome 4 regulate the IL‐1α‐inducible IL8 and CXCL1‐3 genes. Both enhancers engage in dynamic spatial interactions with gene promoters in an IL‐1α/TAK1‐inducible manner. Microdeletions of p65‐binding sites in either of the two enhancers impair NF‐κB recruitment, suppress activation and biallelic transcription of the IL8/CXCL2 genes, and reshuffle higher‐order chromatin interactions as judged by i4C interactome profiles. Notably, these findings support a dominant role of the IL8 “master” enhancer in the regulation of sustained IL‐1α signaling, as well as for IL‐8 and IL‐6 secretion. CRISPR‐guided transactivation of the IL8 locus or cross‐TAD regulation by TNFα‐responsive enhancers in a different model locus supports the existence of complex enhancer hierarchies in response to cytokine stimulation that prime and orchestrate proinflammatory chromatin responses downstream of NF‐κB.