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1.
Purinergic Signal ; 18(1): 13-59, 2022 03.
Article in English | MEDLINE | ID: covidwho-1694363

ABSTRACT

Hyperinflammation plays an important role in severe and critical COVID-19. Using inconsistent criteria, many researchers define hyperinflammation as a form of very severe inflammation with cytokine storm. Therefore, COVID-19 patients are treated with anti-inflammatory drugs. These drugs appear to be less efficacious than expected and are sometimes accompanied by serious adverse effects. SARS-CoV-2 promotes cellular ATP release. Increased levels of extracellular ATP activate the purinergic receptors of the immune cells initiating the physiologic pro-inflammatory immune response. Persisting viral infection drives the ATP release even further leading to the activation of the P2X7 purinergic receptors (P2X7Rs) and a severe yet physiologic inflammation. Disease progression promotes prolonged vigorous activation of the P2X7R causing cell death and uncontrolled ATP release leading to cytokine storm and desensitisation of all other purinergic receptors of the immune cells. This results in immune paralysis with co-infections or secondary infections. We refer to this pathologic condition as hyperinflammation. The readily available and affordable P2X7R antagonist lidocaine can abrogate hyperinflammation and restore the normal immune function. The issue is that the half-maximal effective concentration for P2X7R inhibition of lidocaine is much higher than the maximal tolerable plasma concentration where adverse effects start to develop. To overcome this, we selectively inhibit the P2X7Rs of the immune cells of the lymphatic system inducing clonal expansion of Tregs in local lymph nodes. Subsequently, these Tregs migrate throughout the body exerting anti-inflammatory activities suppressing systemic and (distant) local hyperinflammation. We illustrate this with six critically ill COVID-19 patients treated with lidocaine.


Subject(s)
Adenosine Triphosphate/metabolism , COVID-19/immunology , Cytokine Release Syndrome/etiology , Inflammation/etiology , Lidocaine/therapeutic use , Purinergic P2X Receptor Antagonists/therapeutic use , Receptors, Purinergic/physiology , Anti-Inflammatory Agents/therapeutic use , Critical Care , Cytokine Release Syndrome/drug therapy , Humans , Inflammation/drug therapy , Infusions, Subcutaneous , Lidocaine/administration & dosage , Lidocaine/pharmacology , Lymph Nodes/immunology , Lymphatic System/immunology , Male , Maximum Tolerated Dose , Middle Aged , Models, Immunological , Purinergic P2X Receptor Antagonists/administration & dosage , Purinergic P2X Receptor Antagonists/pharmacology , Receptors, Purinergic/drug effects , Receptors, Purinergic P1/drug effects , Receptors, Purinergic P1/physiology , Receptors, Purinergic P2X7/physiology , Respiratory Distress Syndrome/drug therapy , Respiratory Distress Syndrome/etiology , Signal Transduction , T-Lymphocytes, Regulatory/immunology
2.
BMC Med Res Methodol ; 22(1): 25, 2022 01 20.
Article in English | MEDLINE | ID: covidwho-1643110

ABSTRACT

BACKGROUND: Modern designs for dose-finding studies (e.g., model-based designs such as continual reassessment method) have been shown to substantially improve the ability to determine a suitable dose for efficacy testing when compared to traditional designs such as the 3 + 3 design. However, implementing such designs requires time and specialist knowledge. METHODS: We present a practical approach to developing a model-based design to help support uptake of these methods; in particular, we lay out how to derive the necessary parameters and who should input, and when, to these decisions. Designing a model-based, dose-finding trial is demonstrated using a treatment within the AGILE platform trial, a phase I/II adaptive design for novel COVID-19 treatments. RESULTS: We present discussion of the practical delivery of AGILE, covering what information was found to support principled decision making by the Safety Review Committee, and what could be contained within a statistical analysis plan. We also discuss additional challenges we encountered in the study and discuss more generally what (unplanned) adaptations may be acceptable (or not) in studies using model-based designs. CONCLUSIONS: This example demonstrates both how to design and deliver an adaptive dose-finding trial in order to support uptake of these methods.


Subject(s)
COVID-19 , Pandemics , Bayes Theorem , Dose-Response Relationship, Drug , Humans , Maximum Tolerated Dose , Research Design , SARS-CoV-2
3.
Int J Biol Sci ; 17(12): 3224-3238, 2021.
Article in English | MEDLINE | ID: covidwho-1524470

ABSTRACT

Mechanisms of breast cancer progression and invasion, often involve alteration of hormonal signaling, and upregulation and/or activation of signal transduction pathways that input to cell cycle regulation. Herein, we describe a rationally designed first-in-class novel small molecule inhibitor for targeting oncogenic and hormonal signaling in ER-positive breast cancer. BC-N102 treatment exhibits dose-dependent cytotoxic effects against ER+ breast cancer cell lines. BC-N102 exhibited time course- and dose-dependent cell cycle arrest via downregulation of the estrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR), phosphatidylinositol 3-kinase (PI3K), phosphorylated (p)-extracellular signal-regulated kinase (ERK), p-Akt, CDK2, and CDK4 while increasing p38 mitogen-activated protein kinase (MAPK), and mineralocorticoid receptor (MR) signaling in breast cancer cell line. In addition, we found that BC-N102 suppressed breast cancer tumorigenesis in vivo and prolonged the survival of animals. Our results suggest that the proper application of BC-N102 may be a beneficial chemotherapeutic strategy for ER+ breast cancer patients.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/drug therapy , Cell Cycle Checkpoints/drug effects , Cell Cycle Proteins/metabolism , G1 Phase/drug effects , Receptors, Estrogen/metabolism , Resting Phase, Cell Cycle/drug effects , Animals , Biomarkers, Tumor/genetics , Blotting, Western , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Division , Cell Line, Tumor , Cyclin-Dependent Kinase 2/genetics , Cyclin-Dependent Kinase 4/genetics , Female , Flow Cytometry , Gene Expression Regulation, Neoplastic/physiology , Humans , Maximum Tolerated Dose , Mice , Mice, Nude , Xenograft Model Antitumor Assays
4.
Phytomedicine ; 87: 153591, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1240546

ABSTRACT

BACKGROUND: The outbreak of coronavirus (SARS-CoV-2) disease caused more than 100,000,000 people get infected and over 2,200,000 people being killed worldwide. However, the current developed vaccines or drugs may be not effective in preventing the pandemic of COVID-19 due to the mutations of coronavirus and the severe side effects of the newly developed vaccines. Chinese herbal medicines and their active components play important antiviral activities. Corilagin exhibited antiviral effect on human immunodeficiency virus (HIV), hepatitis C virus (HCV) and Epstein-Barr virus (EBV). However, whether it blocks the interaction between SARS-CoV-2 RBD and hACE2 has not been elucidated. PURPOSE: To characterize an active compound, corilagin derived from Phyllanthus urinaria as potential SARS-CoV-2 entry inhibitors for its possible preventive application in daily anti-virus hygienic products. METHODS: Computational docking coupled with bio-layer interferometry, BLI were adopted to screen more than 1800 natural compounds for the identification of SARS-CoV-2 spike-RBD inhibitors. Corilagin was confirmed to have a strong binding affinity with SARS-CoV-2-RBD or human ACE2 (hACE2) protein by the BLI, ELISA and immunocytochemistry (ICC) assay. Furthermore, the inhibitory effect of viral infection of corilagin was assessed by in vitro pseudovirus system. Finally, the toxicity of corilagin was examined by using MTT assay and maximal tolerated dose (MTD) studies in C57BL/6 mice. RESULTS: Corilagin preferentially binds to a pocket that contains residues Cys 336 to Phe 374 of spike-RBD with a relatively low binding energy of -9.4 kcal/mol. BLI assay further confirmed that corilagin exhibits a relatively strong binding affinity to SARS-CoV-2-RBD and hACE2 protein. In addition, corilagin dose-dependently blocks SARS-CoV-2-RBD binding and abolishes the infectious property of RBD-pseudotyped lentivirus in hACE2 overexpressing HEK293 cells, which mimicked the entry of SARS-CoV-2 virus in human host cells. Finally, in vivo studies revealed that up to 300 mg/kg/day of corilagin was safe in C57BL/6 mice. Our findings suggest that corilagin could be a safe and potential antiviral agent against the COVID-19 acting through the blockade of the fusion of SARS-CoV-2 spike-RBD to hACE2 receptors. CONCLUSION: Corilagin could be considered as a safe and environmental friendly anti-SARS-CoV-2 agent for its potential preventive application in daily anti-virus hygienic products.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , Antiviral Agents/pharmacology , Glucosides/pharmacology , Host-Pathogen Interactions/drug effects , Hydrolyzable Tannins/pharmacology , Spike Glycoprotein, Coronavirus/metabolism , Angiotensin-Converting Enzyme 2/chemistry , Animals , Antiviral Agents/chemistry , Antiviral Agents/toxicity , COVID-19 , Epstein-Barr Virus Infections/drug therapy , Glucosides/chemistry , Glucosides/toxicity , HEK293 Cells , Humans , Hydrolyzable Tannins/chemistry , Hydrolyzable Tannins/toxicity , Lentivirus Infections/drug therapy , Male , Maximum Tolerated Dose , Mice, Inbred C57BL , Molecular Docking Simulation , Spike Glycoprotein, Coronavirus/chemistry
5.
Stat Med ; 40(2): 240-253, 2021 01 30.
Article in English | MEDLINE | ID: covidwho-856116

ABSTRACT

Little has been published in terms of dose-finding methodology in virology. Aside from a few papers focusing on HIV, the considerable progress in dose-finding methodology of the last 25 years has focused almost entirely on oncology. While adverse reactions to cytotoxic drugs may be life threatening, for anti-viral agents we anticipate something different: side effects that provoke the cessation of treatment. This would correspond to treatment failure. On the other hand, success would not be yes/no but would correspond to a range of responses, from small, no more than say 20% reduction in viral load to the complete elimination of the virus. Less than total success matters since this may allow the patient to achieve immune-mediated clearance. The motivation for this article is an upcoming dose-finding trial in chronic norovirus infection. We propose a novel methodology whose goal is twofold: first, to identify the dose that provides the most favorable distribution of treatment outcomes, and, second, to do this in a way that maximizes the treatment benefit for the patients included in the study.


Subject(s)
Antiviral Agents/administration & dosage , Clinical Trials as Topic/statistics & numerical data , Virus Diseases/drug therapy , Dose-Response Relationship, Drug , Drug-Related Side Effects and Adverse Reactions , Humans , Maximum Tolerated Dose , Research Design
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