Inhibitory activities of alginate phosphate and sulfate derivatives against SARS-CoV-2 in vitro.

Alginate derivatives have been demonstrated remarkable antiviral activities. Here we firstly identified polymannuronate phosphate (PMP) as a highly potential anti-SARS-CoV-2 agent. The structure-activity relationship showed polymannuronate monophosphate (PMPD, Mw: 5.8 kDa, P%: 8.7 %) was the most effective component to block the interaction of spike to ACE2 with an IC50 of 85.5 nM. Surface plasmon resonance study indicated that PMPD could bind to spike receptor binding domain (RBD) with the KD value of 78.59 nM. Molecular docking further suggested that the probable binding site of PMPD to spike RBD protein is the interaction interface between spike and ACE2. PMPD has the potential to inhibit the SARS-CoV-2 infection in an independent manner of heparan sulfate proteoglycans. In addition, polyguluronate sulfate (PGS) and propylene glycol alginate sodium sulfate (PSS) unexpectedly showed 3CLpro inhibition with an IC50 of 1.20 µM and 1.42 µM respectively. The polyguluronate backbone and sulfate group played pivotal roles in the 3CLpro inhibition. Overall, this study revealed the potential of PMPD as a novel agent against SARS-CoV-2. It also provided a theoretical basis for further study on the role of PGS and PSS as 3CLpro inhibitors.

Inhibitory activities of alginate phosphate and sulfate derivatives against SARS-CoV-2 in vitro

Alginate derivatives have been demonstrated remarkable antiviral activities. Here we firstly identified polymannuronate phosphate (PMP) as a highly potential anti-SARS-CoV-2 agent. The structure-activity relationship showed polymannuronate monophosphate (PMPD, Mw: 5.8 kDa, P%: 8.7 %) was the most effective component to block the interaction of spike to ACE2 with an IC50 of 85.5 nM. Surface plasmon resonance study indicated that PMPD could bind to spike receptor binding domain (RBD) with the KD value of 78.59 nM. Molecular docking further suggested that the probable binding site of PMPD to spike RBD protein is the interaction interface between spike and ACE2. PMPD has the potential to inhibit the SARS-CoV-2 infection in an independent manner of heparan sulfate proteoglycans. In addition, polyguluronate sulfate (PGS) and propylene glycol alginate sodium sulfate (PSS) unexpectedly showed 3CLpro inhibition with an IC50 of 1.20 μM and 1.42 μM respectively. The polyguluronate backbone and sulfate group played pivotal roles in the 3CLpro inhibition. Overall, this study revealed the potential of PMPD as a novel agent against SARS-CoV-2. It also provided a theoretical basis for further study on the role of PGS and PSS as 3CLpro inhibitors. Graphical Unlabelled Image

Modulating effect of Xuanfei Baidu granule on host metabolism and gut microbiome in rats.

Xuanfei Baidu granule (XFBD) is a recommended patented drug for the prevention and treatment of Corona Virus Disease 2019 (COVID-19), which is approved by the National Medical Products Administration. XFBD suppresses the over-activated immune response caused by inflammatory factor storms in COVID-19 infection. The intestine plays a crucial role in the immune system. The mass spectrometry based fecal metabolomics with 16S rDNA sequencing were combined to evaluate the effects of XFBD on host metabolism and gut microbiome. Short-chain fatty acids (SCFAs) contents in fecal matter were quantified by gas chromatography-mass spectrometry (GC-MS). Plasma samples were used to detect immune and inflammatory levels. The results were verified with a rat model of intestinal disorder. Results indicated that XFBD could increase the immune level of Immunoglobulin A (IgA), Immunoglobulin G (IgG) and Immunoglobulin M (IgM) (p < 0.05). The OPLS-DA analysis results showed that a total of 271 differential metabolites (178 up-regulated and 93 down-regulated) were identified based on the VIP ≥1, p < 0.05, FC ≥ 2 and FC ≤ 0.5. The metabolic pathways mainly involved D-Glutamine and D-glutamate metabolism, Arginine biosynthesis, Biotin metabolism, et al. XFBD modified the gut bacteria structure according to the principal component analysis (PCA), that is, 2 phyla, 3 classes, 5 orders, 11 families and 14 genera were significantly different based on taxonomic assignment. In addition, it could partially callback the relative abundance of intestinal microflora in bacterial disorder rats caused by antibiotics. It is suggested that the intervention mechanism of XFBD might be related to the regulation of intestinal flora composition. The evidence obtained in the study provides a useful reference for understanding the mechanism of XFBD.

Application of multivariate statistical analysis and network pharmacology to explore the mechanism of Danggui Liuhuang Tang in treating perimenopausal syndrome.

ETHNOPHARMACOLOGICAL RELEVANCE: Danggui Liuhuang Tang (DGLHT), first recorded in "Lan-Shi-Mi-Cang" (written in 1276 AD), is a famous classical formula. In 2018, it was listed in the Catalogue of Ancient Classic and Famous Prescriptions (First Batch) formulated by the National Administration of Traditional Chinese Medicine and the National Medical Products Administration. Perimenopausal syndrome (PMS) refers to a series of syndromes with autonomic nervous system dysfunction and neuropsychological symptoms. The treatment of PMS demands non-hormonal drugs. Natural products are considered to be effective substitutes for the treatment of PMS. It is reported that DGLHT has not only good therapeutic effects but also higher safety and fewer side effects in the treatment of PMS. However, the mechanism of DGLHT in treating PMS is not clear. AIM OF THE STUDY: To explore the chemical basis and the mechanism of DGLHT in treating PMS. MATERIALS AND METHODS: Multivariate statistical analysis was used to analyze the difference of components in supernatant before and after compatibility of DGLHT based on LC-MS data. The qualitative analysis was performed on the precipitate formed in the decocting process using LC-MS while the quantitative analysis on the potential markers using LC-UV. Then, the potential markers were analyzed by network pharmacology. The regulatory effect of DGLHT on FSH, P and E2 were carried out in PMS rats. RESULTS: Five potential markers, epiberberine, coptisine, palmatine, berberine and baicalin, were screened from the analysis of compounds in the supernatant. Four complexes, composed of potential marker monomers, were identified in the sediment, including two that have not been reported. The key targets of potential markers include TNF, NOS3, EGFR, ESR1, PTGS2, AR, CDC42 and RPS6KB1. The top signaling pathways include the cGMP-PKG signaling pathway, PI3K-Akt signaling pathway and estrogen signaling pathway. DGLHT could call back the hormone levels of P and E2 in PMS rats. CONCLUSION: DGLHT active ingredients, epiberberine, coptisine, palmatine, berberine and baicalin contribute a lot to the therapeutic effect. And DGLHT takes effect by regulating hormones secreted by the ovary.

COVID-19 Home Quarantine Accelerated the Progression of Myopia in Children Aged 7 to 12 Years in China.

Purpose: To investigate the effect of home quarantine during the COVID-19 pandemic on myopia progression in children and its associated factors. Methods: Myopic children aged 7 to 12 years with regular follow-up visits every half a year from April 2019 to May 2020 were included. Cycloplegic refraction was measured at baseline and at two follow-up visits. The first follow-up visit (visit 1) was conducted before the COVID-19 home quarantine, whereas the second (visit 2) was four months after the home quarantine. Myopia progression at visits 1 and 2 were compared. Factors associated with changes in myopia progression were tested with a multiple regression analysis. Results: In total, 201 myopic children were enrolled. There was a significantly greater change in spherical equivalent at visit 2 (-0.98 ± 0.52 D) than at visit 1 (-0.39 ± 0.58 D; P < 0.001). Students were reported to have spent more time on digital devices for online learning (P < 0.001) and less time on outdoor activities (P < 0.001) at visit 2 than at visit 1. Children using television and projectors had significantly less myopic shift than those using tablets and mobile phones (P < 0.001). More time spent on digital screens (ß = 0.211, P < 0.001), but not less time on outdoor activities (ß = -0.106, P = 0.110), was associated with greater myopia progression at visit 2. Conclusions: Changes in behavior and myopic progression were found during the COVID-19 home quarantine. Myopic progression was associated with digital screen use for online learning, but not time spent on outdoor activities. The projector and television could be better choices for online learning.