ABSTRACT
Objective: Acute liver injury (ALF) is a potential factor of many serious hepatopathies. Carbon tetrachloride (CCl4) is a possible environmental toxicant that can induce ALF. Portulaca oleracea (PO) is one of the most popular edible herbs and has several biological activities such as antioxidant, antimicrobial, anti-inflammatory effects. We explored the significance of PO in regulating inflammatory function in animal models and cultured hepatocytes during liver damage caused by CCl4. Methods: The effect of PO on ALF was evaluated by CCl4-induced mice models in vivo. Hepatic levels of transaminase activities and inflammatory factors were examined. The gene and protein expression of S100A8 and S100A9 were measured by RT-PCR and Western blot analysis. Meanwhile, the efficacy of PO was certified by HepG2 cells in vitro. The transaminase activities, inflammatory factors, and the protein expression of S100A8 and S100A9 were also detected. Results: Animal tests showed that pretreatment with PO reduced the liver pathological tissue damage and the serum levels of ALT, AST, ALT and LDH, as well as reducing the pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α) secretion in CCl4-induced liver injury mice. Simultaneously, HepG2 cells pretreated with PO exhibited a significant decrease in the activities of ALT and AST. Moreover, PO resulted in a significant downregulation of the pro-inflammatory markers S100A8, S100A9 gene and protein expression on CCl4 induced acute liver injury was demonstrated entirely in vivo and vitro experiments. Conclusion: PO may down-regulate S100A8 and S100A9 and inhibit pro-inflammatory cytokines' release, indicating a potential clinical effect for controlling the disease.
ABSTRACT
The severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1) survivors are more likely to produce a potent immune response to SARS-CoV-2 after booster vaccination. We assessed humoral and T cell responses against SARS-CoV-2 in previously vaccinated SARS-CoV-1 survivors and naïve healthy individuals (NHIs) after a booster Ad5-nCoV dose. Boosted SARS-CoV-1 survivors had a high neutralization of SARS-CoV-2 Wuhan-Hu-1 (WA1), Beta, and Delta but is limited to Omicron subvariants (BA.1, BA.2, BA.2.12.1, and BA.4/BA.5). Most boosted SARS-CoV-1 survivors had robust SARS-CoV-2-specific CD4+ and CD8+ T cell responses. While booster vaccination in NHIs elicited less or ineffective neutralization of WA1, Beta, and Delta, and none of them induced neutralizing antibodies against Omicron subvariants. However, they developed comparable SARS-CoV-2-specific T cell responses compared to boosted SARS-CoV-1 survivors. These findings suggest that boosted Ad5-nCoV would not elicit effective neutralizing antibodies against Omicron subvariants in SARS-CoV-1 survivors and NHIs but induced comparable robust T cell responses. Achieving a high antibody titer in SARS-CoV-1 survivors and NHIs is desirable to generate broad neutralization.
