Bioactive compounds from Huashi Baidu decoction possess both antiviral and anti-inflammatory effects against COVID-19.

The coronavirus disease 2019 (COVID-19) pandemic is an ongoing global health concern, and effective antiviral reagents are urgently needed. Traditional Chinese medicine theory-driven natural drug research and development (TCMT-NDRD) is a feasible method to address this issue as the traditional Chinese medicine formulae have been shown effective in the treatment of COVID-19. Huashi Baidu decoction (Q-14) is a clinically approved formula for COVID-19 therapy with antiviral and anti-inflammatory effects. Here, an integrative pharmacological strategy was applied to identify the antiviral and anti-inflammatory bioactive compounds from Q-14. Overall, a total of 343 chemical compounds were initially characterized, and 60 prototype compounds in Q-14 were subsequently traced in plasma using ultrahigh-performance liquid chromatography with quadrupole time-of-flight mass spectrometry. Among the 60 compounds, six compounds (magnolol, glycyrrhisoflavone, licoisoflavone A, emodin, echinatin, and quercetin) were identified showing a dose-dependent inhibition effect on the SARS-CoV-2 infection, including two inhibitors (echinatin and quercetin) of the main protease (Mpro), as well as two inhibitors (glycyrrhisoflavone and licoisoflavone A) of the RNA-dependent RNA polymerase (RdRp). Meanwhile, three anti-inflammatory components, including licochalcone B, echinatin, and glycyrrhisoflavone, were identified in a SARS-CoV-2-infected inflammatory cell model. In addition, glycyrrhisoflavone and licoisoflavone A also displayed strong inhibitory activities against cAMP-specific 3',5'-cyclic phosphodiesterase 4 (PDE4). Crystal structures of PDE4 in complex with glycyrrhisoflavone or licoisoflavone A were determined at resolutions of 1.54 Å and 1.65 Å, respectively, and both compounds bind in the active site of PDE4 with similar interactions. These findings will greatly stimulate the study of TCMT-NDRD against COVID-19.

SARS-CoV-2 Z-RNA activates the ZBP1-RIPK3 pathway to promote virus-induced inflammatory responses.

SARS-CoV-2 infection can trigger strong inflammatory responses and cause severe lung damage in COVID-19 patients with critical illness. However, the molecular mechanisms by which the infection induces excessive inflammatory responses are not fully understood. Here, we report that SARS-CoV-2 infection results in the formation of viral Z-RNA in the cytoplasm of infected cells and thereby activates the ZBP1-RIPK3 pathway. Pharmacological inhibition of RIPK3 by GSK872 or genetic deletion of MLKL reduced SARS-CoV-2-induced IL-1ß release. ZBP1 or RIPK3 deficiency leads to reduced production of both inflammatory cytokines and chemokines during SARS-CoV-2 infection both in vitro and in vivo. Furthermore, deletion of ZBP1 or RIPK3 alleviated SARS-CoV-2 infection-induced immune cell infiltration and lung damage in infected mouse models. These results suggest that the ZBP1-RIPK3 pathway plays a critical role in SARS-CoV-2-induced inflammatory responses and lung damage. Our study provides novel insights into how SARS-CoV-2 infection triggers inflammatory responses and lung pathology, and implicates the therapeutic potential of targeting ZBP1-RIPK3 axis in treating COVID-19.

[Correlation analysis of quality,origin and phenotypic characters of Paris polyphylla var. yunnanensis].

In order to provide guidance for the protection and utilization of resources,quality control and breeding of improved varieties,we compared the main phenotypic characters and quality of wild and transplanted Paris polyphylla var. yunnanensis collected from different producing areas. Seven phenotypic characters of 33 samples of P. polyphylla var. yunnanensis collected from Yunnan,Guizhou and Sichuan were determined by conventional methods,and the principal component analysis and cluster analysis were used to analyze the diversity of the samples. The parissaponin( polyphyllin Ⅰ,Ⅱ,Ⅵ,Ⅶ) content of the samples were detected by HPLC,and analyzed by cluster analysis. Correlation analysis of the phenotypic characters and the parissaponin content was performed. There were significant differences in seven phenotypic characters between wild and transplanted samples of P. polyphylla var. yunnanensis from different habitats,with high phenotypic diversity and abundant genetic variation. The results of principal component analysis showed that leaf shape index was the main factor of morphological variation of P. polyphylla var. yunnanensis. Cluster analysis showed that the phenotypic characters of wild and transplanted P. polyphylla var. yunnanensis could not be completely separated. The content of saponins in wild and transplanted samples from different habitats was quite different. Saponins content of 93. 94% samples met the criterion of Chinese Pharmacopoeia 2015 edition,and the overall quality was relatively steady. The results of independent sample t-test showed that there was no significant difference of all the active ingredient between wild and transplanted samples,and it couldn't be used to distinguish between wild and transplanted samples. It is the same as the results of cluster analysis. The results of correlation analysis showed that the phenotypic traits of P. polyphylla var. yunnanensis were correlated with its medicine quality,and the total content of saponins was positively correlated with leaf length and leaf shape index( r = 0. 389,0. 441; P<0. 05). Yunnan,Guizhou and Sichuan are suitable for the growth of P. polyphylla var. yunnanensis. And the transplaned P. polyphylla var. yunnanensis can be used as the same as the wild ones completely. The results provide reference for the protection and selective breeding of P. polyphylla var. yunnanensis.