Cellular drug response (concentration required for obtaining 50% of a maximum cellular effect, EC 50 ) can be predicted by the intracellular bioavailability (F ic ) and biochemical activity (half-maximal inhibitory concentration, IC 50 ) of drugs. In an ideal model, the cellular negative log of EC 50 (pEC 50 ) equals the sum of log F ic and the negative log of IC 50 (pIC 50 ). Here, we measured F ic 's of remdesivir, favipiravir, and hydroxychloroquine in various cells and calculated their anti-SARS-CoV-2 EC 50 's. The predicted EC 50 's are close to the observed EC 50 's in vitro. When the lung concentrations of antiviral drugs are higher than the predicted EC 50 's in alveolar type 2 cells, the antiviral drugs inhibit virus replication in vivo, and vice versa. Overall, our results indicate that both in vitro and in vivo antiviral activities of drugs can be predicted by their intracellular bioavailability and biochemical activity without using virus. This virus-free strategy can help medicinal chemists and pharmacologists to screen antivirals during early drug discovery, especially for researchers who are not able to work in the high-level biosafety lab.
Accumulating evidence indicates that the mechanical microenvironment exerts profound influences on inflammation and immune modulation, which are likely to be key factors in successful tissue regeneration. The elastic modulus (Em) of the matrix may be a useful adjustable property to control macrophage activation and the overall inflammatory response. This study constituted a series of Em-tunable liquid crystalline cell model (HpCEs) resembling the viscoelastic characteristic of ECM and explored how mechanical microenvironment induced by liquid crystalline soft matter matrix affected macrophage activation and phenotypes. We have shown that HpCEs prepared in this work exhibited typical cholesteric liquid crystal phase and distinct viscoelastic rheological characteristics. All liquid crystalline HpCE matrices facilitated macrophages growth and maintained cell activity. Macrophages in lower-Em HpCE matrices were more likely to polarize toward the pro-inflammatory M1 phenotype. Conversely, the higher-Em HpCEs induced macrophages into an elongated shape and upregulated M2-related markers. Furthermore, the higher-Em HpCEs (HpCE-O1, HpCE-H2, HpCE-H1) could coax sequential polarization states of RAW264.7 from a classically activated “M1” state toward alternatively activated “M2” state in middle and later stage of cell culture (within 3–7 days in this work), suggesting that the HpCE-based strategies could manipulate the local immune microenvironment and promote the dominance of the pro-inflammatory signals in early stages, while M2 macrophages in later stages. The liquid crystalline soft mode fabricated in this work maybe offer a new design guideline for in vitro cell models and applications.
Post-traumatic infection is a serious orthopedic trauma complication commonly caused by Staphylococcus aureus (SAU). ShangKeHuangShui, also known as Yellow Aqueous Concentrate of Traumatology Herbs (YACTH), is prepared from six Chinese herbal medicines, which has been used for decades in our hospital to prevent post-traumatic infection.
In the present study, we investigated the in vitro antibacterial effects and underlying mechanism of YACTH against SAU. YACTH exhibited significant antibacterial activity against SAU with the minimum inhibitory concentration (MIC) of 8.625 mg/mL. Proteomic analysis based on Tandem mass tag (TMT) showed different protein expression levels in SAU under the YACTH and control conditions. Compared to the control group, the expression level of 490 proteins of YACTH treated group significantly changed (>1.2 fold, P <0.05). Biological informatics analysis showed that these differential proteins were widely involved in a variety of biological processes and multiple metabolic pathways. We then selected 26 target proteins to further conduct Parallel reaction monitoring (PRM). The results revealed that the 9 down-regulated proteins were mainly involved in RNA polymerase, oxidative phosphorylation, ABC transporter and glycolysis; whereas, the 17 up-regulated proteins are related to RNA degradation, mismatch repair and ribosome.
In conclusion, YACTH, which contains the water-soluble components of six Chinese herbs, is first reported to exhibit antibacterial activity against SAU in vitro . The results provide novel insights into the antibacterial mechanisms of YACTH on protein networks, which may help us find new potential antibiotic targets.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.