Investigation of the antiviral effects of Saussurea lappa root extract against SARS-CoV-2 virus

SCOPE

The purpose of this study was to look into the antiviral activity of a plant extract derived from the roots of the Saussurea lappa as a food supplement against SARS-CoV-2 infection.

METHODS AND RESULTS

Vero E6 cells were used to test the neutralizing effect of Saussurea lappa extract against the SARS-CoV-2 virus. In our work, we used a real-time cell analyzer that's much more sensitive than the standard endpoint tests for anti-viral effectiveness determination, and a methodology with a very high rate of repetitive results that enables us to see the whole process. This technique allows the accurate monitoring of cell movement and changes in its ability to attach to the surface. The RTCA system is not only a well-known modern technique, but also a unique, noninvasive, and effective instrument for recording the dynamic biological condition of cells. A challenge experiment in mice was planned as a result of the in vitro analysis. A challenge test against SARS-CoV-2 was performed with 10 adult female K18-hACE2 transgenic mice in each group for this purpose. The challenge experiment on mice was based on how the Saussurea lappa extract was used in humans. The mice in Group 1 were gavaged two days before the virus was administered intranasally (in). The control group received PBS instead of the extract (Group 2). 10⁵ TCID₅₀ SARS-CoV-2 virus (Wuhan) was administered intranasally under anesthesia for the first three days of the experiment in the BSL-3 laboratory, and S. lappa extract was administered by gavage in the afternoon. Mice given the S. lappa extract and SARS-CoV-2 virus together survived the study on the 10th day, whereas mice in the control group given the virus and PBS became ill and/or died. In this study, the extract protected the mice against the SARS-CoV-2 virus in 90% of the cases.

CONCLUSIONS

Previous research has shown that the Saussurea plant has anti-inflammatory, antimicrobial, and analgesic properties (22, 33, 44). This study demonstrated its antiviral effect against SARS-CoV-2 in vitro and in vivo models. This article is protected by copyright. All rights reserved.

Identifying specific matrix metalloproteinase-2-inhibiting peptides through phage display-based subtractive screening

Gelatinases A and B, which are members of the matrix metalloproteinase (MMP) family, play essential roles in cancer development and metastasis, as they can break down basal membranes. Therefore, the determination and inhibition of gelatinases is essential for cancer treatment. Peptides that can specifically block each gelatinase may, therefore, be useful for cancer treatment. In this study, subtractive panning was carried out using a 12-mer peptide library to identify peptides that block gelatinase A activity (MMP-2), which is a key pharmacological target. Using this method, 17 unique peptide sequences were determined. MMP-2 inhibition by these peptides was evaluated through zymogram analyses, which revealed that four peptides inhibited MMP-2 activity by at least 65%. These four peptides were synthesized and used for in vitro wound healing using human umbilical vein endothelial cells, and two peptides, AOMP12 and AOMP29, were found to inhibit wound healing by 40%. These peptides are, thus, potential candidates for MMP-2 inhibition for cancer treatment. Furthermore, our findings suggest that our substractive biopanning screening method is a suitable strategy for identifying peptides that selectively inhibit MMP-2.

SARS-CoV-2 neutralizing antibody development strategies

In December 2019 a novel coronavirus was detected in Wuhan City of Hubei Province-China. Owing to a high rate of transmission from human to human, the new virus called SARS-CoV-2 differed from others by its unexpectedly rapid spread. The World Health Organization (WHO) described the most recent coronavirus epidemic as a global pandemic in March 2020. The virus spread triggered a health crisis (the COVID-19 disease) within three months, with socioeconomic implications. No approved targeted-therapies are available for COVID-19, yet. However, it is foreseen that antibody-based treatments may provide an immediate cure for patients. Current neutralizing antibody development studies primarily target the S protein among the structural elements of SARS-CoV-2, which mediates the cell entry of the virus through the angiotensin converting enzyme 2 (ACE2) receptor of host cells. This review aims to provide some of the neutralizing antibody development strategies for SARS-CoV-2 and in vitro and in vivo neutralization assays.

Gonioscopic evaluation of glaucoma patients after trabeculectomy

Seventy-three eyes of 65 patients with various types of glaucoma have been evaluated before and after trabeculectomy. These cases have been examined gonioscopically preoperatively and in the 1st, 3rd, and 6th months. The status of the trabeculectomy defect, and synechiae related to the area, factors predisposing to the development of synechiae, have been looked at. Peripheral anterior synechia formation was more pronounced in chronic angle closure glaucoma, exfoliative glaucoma and secondary glaucoma. The relationship between synechiae and intraocular pressure has been defined. The eyes with total peripheral anterior synechia had a lesser degree of success in lowering the intraocular pressure.