Highly potent dual-targeting angiotensin-converting enzyme 2 (ACE2) and Neuropilin-1 (NRP1) peptides: A promising broad-spectrum therapeutic strategy against SARS-CoV-2 infection

Synthesis, molecular docking, and in vitro activity of a novel angiotensin-converting enzyme 2 inhibitor, LMS1007: a potential molecule in Covid-19 and cancer treatments

Angiotensin-converting enzyme 2 (ACE2) is a validated commonly studied in the pathology of several diseases, including novel coronavirus and breast cancer. Herein, we report the synthesis, molecular docking, and validation of a novel ACE2 inhibitor that was previously discovered by our team based on diverse scaffolds of other ACE2 inhibitors and carnosine. The synthesized 4-subsitituted imidazole compound, namely, LMS1007, was characterized through 1H-NMR, LC-MS, and SFC. LMS1007 was then tested in vitro with ACE2 and viral spike protein-ACE2 inhibitor kits and was found to be approximately 100 times more potent as an ACE2 inhibitor than carnosine. However, it was less potent than the standard ACE2 inhibitor. In the same concentration range of the standard drug for ACE2 inhibition, LMS1007 demonstrated similar inhibitory effects on the interaction of the viral spike protein with ACE2. LMS1007 had an inhibitory concentration of 50% (IC50) at a concentration of 2.3 mM in all kits. LMS1007, similar to carnosine in breast cancer cell lines, exhibited potential inhibitory effects on the ACE2-mediated host uptake of Covid-19. Thus, a thorough review and discussion are provided on the role of ACE2 as an attractive target for the development of new drugs for Covid-19 treatment.

Discovery of a highly potent, selective, and stable d-amino acid-containing peptide inhibitor of CDK9/cyclin T1 interaction for the treatment of prostate cancer

Cyclin-dependent kinase 9 (CDK9) plays a pivotal role in promoting oncogenic transcriptional pathways, significantly contributing to the development and progression of cancer. Given the unique biostability of d-amino acid, the development of d-amino acid-containing peptides (DAACPs) is a promising strategy for cancer treatment. Currently, no DAACPs inhibitor targeting CDK9-cyclin T1 have been reported. Here, we reported the identification of a novel, highly potent, selective and stable DAACPs inhibitor (peptide-5) targeting CDK9-cyclin T1 interaction. Peptide-5 showed nanomolar inhibitory effect against CDK9-cyclin T1 (IC50 = 4.16 ± 0.11 nM). Molecular dynamics (MD) simulation exhibited that peptide-5 stably bound to CDK9. Peptide-5 showed good inhibitory activity against multiple types of prostate cancer cells and demonstrated good biostability in mouse serum. Moreover, peptide-5 suppresses the tumor growth in DU145 cell-derived xenografts nude mice. These data suggest that peptide-5 is a potent antitumor candidate for further research.

Pseudotyped Viruses: A Useful Platform for Pre-Clinical Studies Conducted in a BSL-2 Laboratory Setting

The study of pathogenic viruses has always posed significant biosafety challenges. In particular, the study of highly pathogenic viruses requires methods with low biological risk but relatively high sensitivity and convenience in detection. In recent years, pseudoviruses, which consist of a backbone of one virus and envelope proteins of another virus, have become one of the most widely used tools for exploring the mechanisms of viruses binding to cells, membrane fusion and viral entry, as well as for screening the libraries of antiviral substances, evaluating the potential of neutralizing monoclonal antibodies, developing neutralization tests, and therapeutic platforms. During the outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), pseudotyped virus-based assays played a pivotal role in advancing our understanding of virus-cell interactions and the role of its proteins in disease pathogenesis. Such tools facilitated the search for potential therapeutic agents and accelerated epidemiological studies on post-infection and post-vaccination humoral immunity. This review focuses on the use of pseudoviruses as a model for large-scale applications to study enveloped viruses.

Substance P - a regulatory peptide with defense and repair functions. Results and perspectives for the fight against COVID-19

Severe acute respiratory syndrome corona virus 2 (SARS CoV-2) is the cause of Corona virus disease 2019 (COVID-19), which turned into a pandemic in late 2019 and early 2020. SARS CoV-2 causes endothelial cell destruction and swelling, microthrombosis, constriction of capillaries, and malfunction of pericytes, all of which are detrimental to capillary integrity, angiogenesis, and healing processes. Cytokine storming has been connected to COVID-19 disease. Hypoxemia and tissue hypoxia may arise from impaired oxygen diffusion exchange in the lungs due to capillary damage and congestion. This personal view will look at how inflammation and capillary damage affect blood and tissue oxygenation, cognitive function, and the duration and intensity of COVID-19 disease. The general effects of microvascular injury, hypoxia, and capillary damage caused by COVID-19 in key organs are also covered in this point of view. Once initiated, this vicious cycle leads to diminished capillary function, which exacerbates inflammation and tissue damage, and increased inflammation due to hypoxia. Brain damage may result from low oxygen levels and high cytokines in brain tissue. In this paper we give a summary in this direction with focus on the role of the neuropeptide Substance P. On the basis of this, we discuss selected approaches to the question: "How Substance P is involved in the etiology of the COVID-19 and how results of our research could improve the prevention or therapy of corona? Thereby pointing out the role of Substance P in the post-corona syndrome and providing novel concepts for therapy and prevention.

Alterations in microbiota of patients with COVID-19: implications for therapeutic interventions

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recently caused a global pandemic, resulting in more than 702 million people being infected and over 6.9 million deaths. Patients with coronavirus disease (COVID-19) may suffer from diarrhea, sleep disorders, depression, and even cognitive impairment, which is associated with long COVID during recovery. However, there remains no consensus on effective treatment methods. Studies have found that patients with COVID-19 have alterations in microbiota and their metabolites, particularly in the gut, which may be involved in the regulation of immune responses. Consumption of probiotics may alleviate the discomfort caused by inflammation and oxidative stress. However, the pathophysiological process underlying the alleviation of COVID-19-related symptoms and complications by targeting the microbiota remains unclear. In the current study, we summarize the latest research and evidence on the COVID-19 pandemic, together with symptoms of SARS-CoV-2 and vaccine use, with a focus on the relationship between microbiota alterations and COVID-19-related symptoms and vaccine use. This work provides evidence that probiotic-based interventions may improve COVID-19 symptoms by regulating gut microbiota and systemic immunity. Probiotics may also be used as adjuvants to improve vaccine efficacy.