Ocimum flavone Orientin as a countermeasure for thrombocytopenia

Alnustone promotes megakaryocyte differentiation and platelet production via the interleukin-17A/interleukin-17A receptor/Src/RAC1/MEK/ERK signaling pathway

OBJECTIVES

Thrombocytopenia is a disease in which the number of platelets in the peripheral blood decreases. It can be caused by multiple genetic factors, and numerous challenges are associated with its treatment. In this study, the effects of alnustone on megakaryocytes and platelets were investigated, with the aim of developing a new therapeutic approach for thrombocytopenia.

METHODS

Random forest algorithm was used to establish a drug screening model, and alnustone was identified as a natural active compound that could promote megakaryocyte differentiation. The effect of alnustone on megakaryocyte activity was determined using cell counting kit-8. The effect of alnustone on megakaryocyte differentiation was determined using flow cytometry, Giemsa staining, and phalloidin staining. A mouse model of thrombocytopenia was established by exposing mice to X-rays at 4 Gy and was used to test the bioactivity of alnustone in vivo. The effect of alnustone on platelet production was determined using zebrafish. Network pharmacology was used to predict targets and signaling pathways. Western blotting and immunofluorescence staining determined the expression levels of proteins.

RESULTS

Alnustone promoted the differentiation and maturation of megakaryocytes in vitro and restored platelet production in thrombocytopenic mice and zebrafish. Network pharmacology and western blotting showed that alnustone promoted the expression of interleukin-17A and enhanced its interaction with its receptor, and thereby regulated downstream MEK/ERK signaling and promoted megakaryocyte differentiation.

CONCLUSIONS

Alnustone can promote megakaryocyte differentiation and platelet production via the interleukin-17A/interleukin-17A receptor/Src/RAC1/MEK/ERK signaling pathway and thus provides a new therapeutic strategy for the treatment of thrombocytopenia.

Xanthotoxin, a novel inducer of platelet formation, promotes thrombocytopoiesis via IL-1R1 and MEK/ERK signaling

BACKGROUND

Thrombocytopenia is a common hematological disease caused by many factors. It usually complicates critical diseases and increases morbidity and mortality. The treatment of thrombocytopenia remains a great challenge in clinical practice, however, its treatment options are limited. In this study, the active monomer xanthotoxin (XAT) was screened out to explore its medicinal value and provide novel therapeutic strategies for the clinical treatment of thrombocytopenia.

METHODS

The effects of XAT on megakaryocyte differentiation and maturation were detected by flow cytometry, Giemsa and phalloidin staining. RNA-seq identified differentially expressed genes and enriched pathways. The signaling pathway and transcription factors were verified through WB and immunofluorescence staining. Tg (cd41: eGFP) transgenic zebrafish and mice with thrombocytopenia were used to evaluate the biological activity of XAT on platelet formation and the related hematopoietic organ index in vivo.

RESULTS

XAT promoted the differentiation and maturation of Meg-01 cells in vitro. Meanwhile, XAT could stimulate platelet formation in transgenic zebrafish and recover platelet production and function in irradiation-induced thrombocytopenia mice. Further RNA-seq prediction and WB verification revealed that XAT activates the IL-1R1 target and MEK/ERK signaling pathway, and upregulates the expression of transcription factors related to the hematopoietic lineage to promote megakaryocyte differentiation and platelet formation.

CONCLUSION

XAT accelerates megakaryocyte differentiation and maturation to promote platelet production and recovery through triggering IL-1R1 and activating the MEK/ERK signaling pathway, providing a new pharmacotherapy strategy for thrombocytopenia.

The Application of Ethnomedicine in Modulating Megakaryocyte Differentiation and Platelet Counts

Megakaryocytes (MKs), a kind of functional hematopoietic stem cell, form platelets to maintain platelet balance through cell differentiation and maturation. In recent years, the incidence of blood diseases such as thrombocytopenia has increased, but these diseases cannot be fundamentally solved. The platelets produced by MKs can treat thrombocytopenia-associated diseases in the body, and myeloid differentiation induced by MKs has the potential to improve myelosuppression and erythroleukemia. Currently, ethnomedicine is extensively used in the clinical treatment of blood diseases, and the recent literature has reported that many phytomedicines can improve the disease status through MK differentiation. This paper reviewed the effects of botanical drugs on megakaryocytic differentiation covering the period 1994-2022, and information was obtained from PubMed, Web of Science and Google Scholar. In conclusions, we summarized the role and molecular mechanism of many typical botanical drugs in promoting megakaryocyte differentiation in vivo, providing evidence as much as possible for botanical drugs treating thrombocytopenia and other related diseases in the future.

Two-miRNA-based finger-stick assay for estimation of absorbed ionizing radiation dose

Nuclear radiation and radioactive fallouts resulting from a nuclear weapon detonation or reactor accidents could result in injuries affecting multiple sensitive organs, defined as acute radiation syndrome (ARS). Rapid and early estimation of injuries to sensitive organs using markers of radiation response is critical for identifying individuals who could potentially exhibit ARS; however, there are currently no biodosimetry assays approved for human use. We developed a sensitive microRNA (miRNA)-based blood test for radiation dose reconstruction with ±0.5 Gy resolution at critical dose range. Radiation dose-dependent changes in miR-150-5p in blood were internally normalized by a miRNA, miR-23a-3p, that was nonresponsive to radiation. miR-23a-3p was not highly expressed in blood cells but was abundant in circulation and was released primarily from the lung. Our assay showed the capability for dose estimation within hours to 1 week after exposure using a drop of blood from mice. We tested this biodosimetry assay for estimation of absorbed ionizing radiation dose in mice of varying ages and after exposure to both improvised nuclear device (IND)-spectrum neutrons and gamma rays. Leukemia specimens from patients exposed to fractionated radiation showed depletion of miR-150-5p in blood. We bridged the exposure of these patients to fractionated radiation by comparing responses after fractionated versus single acute exposure in mice. Although validation in nonhuman primates is needed, this proof-of-concept study suggests the potential utility of this assay in radiation disaster management and clinical applications.

Composition of the metabolomic bio-coronas isolated from Ocimum sanctum and Rubia tinctorum

Objective

Nanoharvesting from intact plants, organs, and cultured cells is a method in which nanoparticles are co-incubated with the target tissue, which leads to the internalization of nanoparticles. Internalized nanoparticles are coated in situ with specific metabolites that form a dynamic surface layer called a bio-corona. Our previous study showed that metabolites that form the bio-corona around anatase TiO₂ nanoparticles incubated with leaves of the model plant Arabidopsis thaliana are enriched for flavonoids and lipids. The present study focused on the identification of metabolites isolated by nanoharvesting from two medicinal plants, Ocimum sanctum (Tulsi) and Rubia tinctorum (common madder).

Results

To identify metabolites that form the bio-corona, Tulsi leaves and madder roots were incubated with ultra-small anatase TiO₂ nanoparticles, the coated nanoparticles were collected, and the adsorbed molecules were released from the nanoparticle surface and analyzed using an untargeted metabolomics approach. Similar to the results in which Arabidopsis tissue was used as a source of metabolites, TiO₂ nanoparticle bio-coronas from Tulsi and madder were enriched for flavonoids and lipids, suggesting that nanoharvesting has a wide-range application potential. The third group of metabolites enriched in bio-coronas isolated from both plants were small peptides with C-terminal arginine and lysine residues.

Molecular docking study of flavonoid compounds for possible matrix metalloproteinase-13 inhibition

OBJECTIVES

Matrix metalloproteinase-13 (MMP-13) has been reported to be involved in different biological processes such as degradation of extracellular matrix proteins, activating or degrading some significant regulatory proteins, wound healing, tissue remodeling, cartilage degradation, bone development, bone mineralization, ossification, cell migration, and tumor cell invasion. Further, MMP-13 participates in many oral diseases such as tooth decay, gingivitis, and degradation of enamel and tissue around the implant. In addition, inhibition of MMP-13 has shown therapeutic properties for Alzheimer's disease (AD). We performed molecular docking to assess the binding affinity of 29 flavonoid compounds with the MMP-13. Additionally, pharmacokinetic and toxicity characteristics of the top-ranked flavonoids were studied. The current study also intended to identify the most important amino acids involved in the inhibition of MMP-13 based on topological feature (degree) in the ligand-amino acid network for MMP-13.

METHODS

Molecular docking and network analysis were studied using AutoDock and Cytoscape software, respectively. Pharmacokinetic and toxicity characteristics of compounds were predicted using bioinformatics web tools.

RESULTS

The results revealed that nine of the studied flavonoids had considerable estimated free energy of binding and inhibition constant: Rutin, nicotiflorin, orientin, vitexin, apigenin-7-glucoside, quercitrin, isoquercitrin, quercitrin-3-rhamnoside, and vicenin-2. Proline-242 was found to be the most important amino acid inhibiting the enzyme.

CONCLUSIONS

The results of the current study may be helpful in the prevention and therapeutic procedures of many disorders such as cancer, tooth caries, and AD. Nevertheless, validation tests are required in the future.

Ethnomedicines of Indian origin for combating COVID-19 infection by hampering the viral replication: using structure-based drug discovery approach

In the present study, we have explored the interaction of the active components from 10 different medicinal plants of Indian origin that are commonly used for treating cold and respiratory-related disorders, through molecular docking analysis. In the current scenario, COVID-19 patients experience severe respiratory syndromes, hence it is envisaged from our study that these traditional medicines are very likely to provide a favourable effect on COVID-19 infections. The active ingredients identified from these natural products are previously reported for antiviral activities against large group of viruses. Totally 47 bioactives identified from the medicinal plants were investigated against the structural targets of SARS-CoV-2 (Mpro and spike protein) and human ACE2 receptor. The top leads were identified based on interaction energies, number of hydrogen bond and other parameters that explain their potency to inhibit SARS-CoV-2. The bioactive ligands such as Cucurbitacin E, Orientin, Bis-andrographolide, Cucurbitacin B, Isocucurbitacin B, Vitexin, Berberine, Bryonolic acid, Piperine and Magnoflorine targeted the hotspot residues of SARS-CoV-2 main protease. In fact, this protease enzyme has an essential role in mediating the viral replication and therefore compounds targeting this key enzyme are expected to block the viral replication and transcription. The top scoring conformations identified through docking analysis were further demonstrated with molecular dynamics simulation. Besides, the stability of the conformation was studied in detail by investigating the binding free energy using MM-PBSA method. Overall, the study emphasized that the proposed hit Cucurbitacin E and orientin could serve as a promising scaffold for developing anti-COVID-19 drug.

Communicated by Ramaswamy H. Sarma