Discovery of a novel megakaryopoiesis enhancer, ingenol, promoting thrombopoiesis through PI3K-Akt signaling independent of thrombopoietin

Sheng Xue Ning as a Novel Agent that Promotes SCF-Driven Hematopoietic Stem/Progenitor Cell Proliferation to Promote Erythropoiesis

Stimulating erythropoiesis is essential in the treatment of various types of anemia. Sheng Xue Ning (SXN) is commonly used in China as an iron supplement to treat iron deficiency anemia, renal anemia, and anemia in pregnancy. This research reports a novel effect of SXN in enhancing the proliferation of hematopoietic stem/progenitor cell (HSPC) to promote erythropoiesis in the bone marrow, which is distinct from conventional iron supplements that primarily aid in the maturation of red blood cells. Employing a model of hematopoietic dysfunction induced by X-ray exposure, we evaluated the efficacy of SXN in restoring hematopoietic function. SXN significantly promoted the recovery of peripheral erythroid cells and enhanced the proliferation and differentiation of Lin-/c-KIT+/Sca-1+ HSPC in mice exposed to X-ray irradiation. Our results showed that SXN elevated the expression of stem cell factor (SCF) and activated the SCF/c-KIT/PI3K/AKT signaling pathway, facilitating the proliferation and differentiation of HSPC. In vitro, SXN markedly enhanced the proliferation of bone marrow nucleated cell (BMNC) and the colony-forming capacity of BFU-E, CFU-E, and CFU-GM, while also elevating the expression of proteins involved in the SCF/c-KIT/PI3K/AKT pathway in BMNC. Additionally, SXN enhanced the proliferation and differentiation of mesenchymal stem cell (MSC) and increased SCF secretion. In conclusion, SXN demonstrates the capacity to enhance erythropoiesis by upregulating SCF expression, thereby promoting HSPC proliferation and differentiation via the SCF/c-KIT/PI3K/AKT pathway. SXN may offer a new strategy for improving the activity of HSPC and promoting erythropoiesis in the treatment of hematopoiesis disorders.

Identification of Active Molecules against Thrombocytopenia through Machine Learning

Thrombocytopenia, which is associated with thrombopoietin (TPO) deficiency, presents very limited treatment options and can lead to life-threatening complications. Discovering new therapeutic agents against thrombocytopenia has proven to be a challenging task using traditional screening approaches. Fortunately, machine learning (ML) techniques offer a rapid avenue for exploring chemical space, thereby increasing the likelihood of uncovering new drug candidates. In this study, we focused on computational modeling for drug-induced megakaryocyte differentiation and platelet production using ML methods, aiming to gain insights into the structural characteristics of hematopoietic activity. We developed 112 different classifiers by combining eight ML algorithms with 14 molecule features. The top-performing model achieved good results on both 5-fold cross-validation (with an accuracy of 81.6% and MCC value of 0.589) and external validation (with an accuracy of 83.1% and MCC value of 0.642). Additionally, by leveraging the Shapley additive explanations method, the best model provided quantitative assessments of molecular properties and structures that significantly contributed to the predictions. Furthermore, we employed an ensemble strategy to integrate predictions from multiple models and performed in silico predictions for new molecules with potential activity against thrombocytopenia, sourced from traditional Chinese medicine and the Drug Repurposing Hub. The findings of this study could offer valuable insights into the structural characteristics and computational prediction of thrombopoiesis inducers.

An Innovative Inducer of Platelet Production, Isochlorogenic Acid A, Is Uncovered through the Application of Deep Neural Networks

(1) Background: Radiation-induced thrombocytopenia (RIT) often occurs in cancer patients undergoing radiation therapy, which can result in morbidity and even death. However, a notable deficiency exists in the availability of specific drugs designed for the treatment of RIT. (2) Methods: In our pursuit of new drugs for RIT treatment, we employed three deep learning (DL) algorithms: convolutional neural network (CNN), deep neural network (DNN), and a hybrid neural network that combines the computational characteristics of the two. These algorithms construct computational models that can screen compounds for drug activity by utilizing the distinct physicochemical properties of the molecules. The best model underwent testing using a set of 10 drugs endorsed by the US Food and Drug Administration (FDA) specifically for the treatment of thrombocytopenia. (3) Results: The Hybrid CNN+DNN (HCD) model demonstrated the most effective predictive performance on the test dataset, achieving an accuracy of 98.3% and a precision of 97.0%. Both metrics surpassed the performance of the other models, and the model predicted that seven FDA drugs would exhibit activity. Isochlorogenic acid A, identified through screening the Chinese Pharmacopoeia Natural Product Library, was subsequently subjected to experimental verification. The results indicated a substantial enhancement in the differentiation and maturation of megakaryocytes (MKs), along with a notable increase in platelet production. (4) Conclusions: This underscores the potential therapeutic efficacy of isochlorogenic acid A in addressing RIT.

Targeting CD38/ ADP-ribosyl cyclase as a novel therapeutic strategy for identification of three potent agonists for leukopenia treatment

Leukopenia is the most common side effect of chemotherapy and radiotherapy. It potentially deteriorates into a life-threatening complication in cancer patients. Despite several agents being approved for clinical administration, there are still high incidences of pathogen-related disease due to a lack of functional immune cells. ADP-ribosyl cyclase of CD38 displays a regulatory effect on leukopoiesis and the immune system. To explore whether the ADP-ribosyl cyclase was a potential therapeutic target of leukopenia. We established a drug screening model based on an ADP-ribosyl cyclase-based pharmacophore generation algorithm and discovered three novel ADP-ribosyl cyclase agonists: ziyuglycoside II (ZGSII), brevifolincarboxylic acid (BA), and 3,4-dihydroxy-5-methoxybenzoic acid (DMA). Then, in vitro experiments demonstrated that these three natural compounds significantly promoted myeloid differentiation and antibacterial activity in NB4 cells. In vivo, experiments confirmed that the compounds also stimulated the recovery of leukocytes in irradiation-induced mice and zebrafish. The mechanism was investigated by network pharmacology, and the top 12 biological processes and the top 20 signaling pathways were obtained by intersecting target genes among ZGSII, BA, DMA, and leukopenia. The potential signaling molecules involved were further explored through experiments. Finally, the ADP-ribosyl cyclase agonists (ZGSII, BA, and DMA) has been found to regenerate microbicidal myeloid cells to effectively ameliorate leukopenia-associated infection by activating CD38/ADP-ribosyl cyclase-Ca2+-NFAT. In summary, this study constructs a drug screening model to discover active compounds against leukopenia, reveals the critical roles of ADP-ribosyl cyclase in promoting myeloid differentiation and the immune response, and provides a promising strategy for the treatment of radiation-induced leukopenia.

Interleukins in Platelet Biology: Unraveling the Complex Regulatory Network

Interleukins, a diverse family of cytokines produced by various cells, play crucial roles in immune responses, immunoregulation, and a wide range of physiological and pathological processes. In the context of megakaryopoiesis, thrombopoiesis, and platelet function, interleukins have emerged as key regulators, exerting significant influence on the development, maturation, and activity of megakaryocytes (MKs) and platelets. While the therapeutic potential of interleukins in platelet-related diseases has been recognized for decades, their clinical application has been hindered by limitations in basic research and challenges in drug development. Recent advancements in understanding the molecular mechanisms of interleukins and their interactions with MKs and platelets, coupled with breakthroughs in cytokine engineering, have revitalized the field of interleukin-based therapeutics. These breakthroughs have paved the way for the development of more effective and specific interleukin-based therapies for the treatment of platelet disorders. This review provides a comprehensive overview of the effects of interleukins on megakaryopoiesis, thrombopoiesis, and platelet function. It highlights the potential clinical applications of interleukins in regulating megakaryopoiesis and platelet function and discusses the latest bioengineering technologies that could improve the pharmacokinetic properties of interleukins. By synthesizing the current knowledge in this field, this review aims to provide valuable insights for future research into the clinical application of interleukins in platelet-related diseases.

Hirsutine, an Emerging Natural Product with Promising Therapeutic Benefits: A Systematic Review

Fruits and vegetables are used not only for nutritional purposes but also as therapeutics to treat various diseases and ailments. These food items are prominent sources of phytochemicals that exhibit chemopreventive and therapeutic effects against several diseases. Hirsutine (HSN) is a naturally occurring indole alkaloid found in various Uncaria species and has a multitude of therapeutic benefits. It is found in foodstuffs such as fish, seafood, meat, poultry, dairy, and some grain products among other things. In addition, it is present in fruits and vegetables including corn, cauliflower, mushrooms, potatoes, bamboo shoots, bananas, cantaloupe, and citrus fruits. The primary emphasis of this study is to summarize the pharmacological activities and the underlying mechanisms of HSN against different diseases, as well as the biopharmaceutical features. For this, data were collected (up to date as of 1 July 2023) from various reliable and authentic literature by searching different academic search engines, including PubMed, Springer Link, Scopus, Wiley Online, Web of Science, ScienceDirect, and Google Scholar. Findings indicated that HSN exerts several effects in various preclinical and pharmacological experimental systems. It exhibits anti-inflammatory, antiviral, anti-diabetic, and antioxidant activities with beneficial effects in neurological and cardiovascular diseases. Our findings also indicate that HSN exerts promising anticancer potentials via several molecular mechanisms, including apoptotic cell death, induction of oxidative stress, cytotoxic effect, anti-proliferative effect, genotoxic effect, and inhibition of cancer cell migration and invasion against various cancers such as lung, breast, and antitumor effects in human T-cell leukemia. Taken all together, findings from this study show that HSN can be a promising therapeutic agent to treat various diseases including cancer.

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.

Identification of thrombopoiesis inducer based on a hybrid deep neural network model

Thrombocytopenia is a common haematological problem worldwide. Currently, there are no relatively safe and effective agents for the treatment of thrombocytopenia. To address this challenge, we propose a computational method that enables the discovery of novel drug candidates with haematopoietic activities. Based on different types of molecular representations, three deep learning (DL) algorithms, namely recurrent neural networks (RNNs), deep neural networks (DNNs), and hybrid neural networks (RNNs+DNNs), were used to develop classification models to distinguish between active and inactive compounds. The evaluation results illustrated that the hybrid DL model exhibited the best prediction performance, with an accuracy of 97.8 % and Matthews correlation coefficient of 0.958 on the test dataset. Subsequently, we performed drug discovery screening based on the hybrid DL model and identified a compound from the FDA-approved drug library that was structurally divergent from conventional drugs and showed a potential therapeutic action against thrombocytopenia. The novel drug candidate wedelolactone significantly promoted megakaryocyte differentiation in vitro and increased platelet levels and megakaryocyte differentiation in irradiated mice with no systemic toxicity. Overall, our work demonstrates how artificial intelligence can be used to discover novel drugs against thrombocytopenia.

The combination of machine learning and transcriptomics reveals a novel megakaryopoiesis inducer, MO-A, that promotes thrombopoiesis by activating FGF1/FGFR1/PI3K/Akt/NF-κB signaling

Radiation-induced thrombocytopenia (RIT) occurs widely and causes high mortality and morbidity in cancer patients who receive radiotherapy. However, specific drugs for treating RIT remain woefully inadequate. Here, we first developed a drug screening model using naive Bayes, a machine learning (ML) algorithm, to virtually screen the active compounds promoting megakaryopoiesis and thrombopoiesis. A natural product library was screened by the model, and methylophiopogonanone A (MO-A) was identified as the most active compound. The activity of MO-A was then validated in vitro and showed that MO-A could markedly induce megakaryocyte (MK) differentiation of K562 and Meg-01 cells in a concentration-dependent manner. Furthermore, the therapeutic action of MO-A on RIT was evaluated, and MO-A significantly accelerated platelet level recovery, platelet activation, megakaryopoiesis, MK differentiation in RIT mice. Moreover, RNA-sequencing (RNA-seq) indicated that the PI3K cascade was closely related to MK differentiation induced by MO-A. Finally, experimental verification demonstrated that MO-A obviously induced the expression of FGF1 and FGFR1, and increased the phosphorylation of PI3K, Akt and NF-κB. Blocking FGFR1 with its inhibitor dovitinib suppressed MO-A-induced MK differentiation, and PI3K, Akt and NF-κB phosphorylation. Similarly, inhibition of PI3K-Akt signal pathway by its inhibitor LY294002 suppressed MK differentiation, and PI3K, Akt and NF-κB phosphorylation induced by MO-A. Taken together, our study provides an efficient drug discovery strategy for hematological diseases, and demonstrates that MO-A is a novel countermeasure for treating RIT through activation of the FGF1/FGFR1/PI3K/Akt/NF-κB signaling pathway.

Application and investigation of thrombopoiesis-stimulating agents in the treatment of thrombocytopenia

Platelets, derived from a certain subpopulation of megakaryocytes, are closely related to hemostasis, coagulation, metastasis, inflammation, and cancer progression. Thrombopoiesis is a dynamic process regulated by various signaling pathways in which thrombopoietin (THPO)-MPL is dominant. Thrombopoiesis-stimulating agents could promote platelet production, showing therapeutic effects in different kinds of thrombocytopenia. Some thrombopoiesis-stimulating agents are currently used in clinical practices to treat thrombocytopenia. The others are not in clinical investigations to deal with thrombocytopenia but have potential in thrombopoiesis. Their potential values in thrombocytopenia treatment should be highly regarded. Novel drug screening models and drug repurposing research have found many new agents and yielded promising outcomes in preclinical or clinical studies. This review will briefly introduce thrombopoiesis-stimulating agents currently or potentially valuable in thrombocytopenia treatment and summarize the possible mechanisms and therapeutic effects, which may enrich the pharmacological armamentarium for the medical treatment of 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.

Caulis Polygoni Multiflori Accelerates Megakaryopoiesis and Thrombopoiesis via Activating PI3K/Akt and MEK/ERK Signaling Pathways

Thrombocytopenia is one of the most common complications of cancer therapy. Until now, there are still no satisfactory medications to treat chemotherapy and radiation-induced thrombocytopenia (CIT and RIT, respectively). Caulis Polygoni Multiflori (CPM), one of the most commonly used Chinese herbs, has been well documented to nourish blood for tranquilizing the mind and treating anemia, suggesting its beneficial effect on hematopoiesis. However, it is unknown whether CPM can accelerate megakaryopoiesis and thrombopoiesis. Here, we employ a UHPLC Q–Exactive HF-X mass spectrometer (UHPLC QE HF-X MS) to identify 11 ingredients in CPM. Then, in vitro experiments showed that CPM significantly increased megakaryocyte (MK) differentiation and maturation but did not affect apoptosis and lactate dehydrogenase (LDH) release of K562 and Meg-01 cells. More importantly, animal experiments verified that CPM treatment markedly accelerated platelet recovery, megakaryopoiesis and thrombopoiesis in RIT mice without hepatic and renal toxicities in vivo. Finally, RNA-sequencing (RNA-seq) and western blot were used to determine that CPM increased the expression of proteins related to PI3K/Akt and MEK/ERK (MAPK) signaling pathways. On the contrary, blocking PI3K/Akt and MEK/ERK signaling pathways with their specific inhibitors suppressed MK differentiation induced by CPM. In conclusion, for the first time, our study demonstrates that CPM may be a promised thrombopoietic agent and provide an experimental basis for expanding clinical use.

A comprehensive review of Rubia cordifolia L.: Traditional uses, phytochemistry, pharmacological activities, and clinical applications

Rubia cordifolia (family: Rubiaceae) L (R. cordifolia) is a perennial botanical drug climbing vine. As the main part of the traditional Chinese medicine, the rhizome has a long history. A great number of literary studies have reported that it can be used for the improvement of blood circulation, hemostasis, activation of collaterals, etc. When it comes to the wide application of R. cordifolia in traditional medicine, we systematically review its traditional uses, phytochemistry and pharmacological effects. Literatures were systematically searched using several scientific databases, including China National Knowledge Infrastructure (CNKI), Baidu Scholar, PubMed, Web of Science, and other professional websites. Kew Botanical Garden and the iPlant were used for obtaining the scientific names and plant images of R. cordifolia. In addition, other information was also gathered from books including traditional Chinese herbal medicine, the Chinese Pharmacopoeia, and Chinese Materia Medica. So far, many prescriptions containing R. cordifolia have been widely used in the clinical treatment of abnormal uterine bleeding, primary dysmenorrhea and other gynecological diseases, allergic purpura, renal hemorrhage and other diseases. The phytochemistry studies have reported that more than 100 compounds are found in R. cordifolia, such as bicyclic peptides, terpenes, polysaccharides, trace elements, flavonoids, and quinones. Among them, quinones and peptides are the types of components with the highest contents in R. cordifolia. The modern pharmacological studies have revealed that R. cordifolia and its derived components have anti-tumor, anti-oxidative, anti-platelet aggregation, and anti-inflammatory effects. However, most studies are preclinical. The pharmacological mechanism of R. cordifolia has not been thoroughly studied. In addition, there are few pharmacokinetic and toxicity studies of R. cordifolia, therefore the clinical safety data for R. cordifolia is lacking. To sum up, this review for the first time summarizes a systemic and integrated traditional uses, chemical compositions, pharmacological actions and clinical applications of R. cordifolia, which provides the novel and full-scale insight for the drug development, medicinal value, and application of R. cordifolia in the future.

Systemic lupus erythematosus-complicating immune thrombocytopenia: From pathogenesis to treatment

Immune thrombocytopenia (ITP) is a common hematological manifestation of systemic lupus erythematosus (SLE). The heterogeneity of its clinical characteristics and therapeutic responses reflects a complex pathogenesis. A better understanding of its pathophysiological mechanisms and employing an optimal treatment regimen is therefore important to improve the response rate and prognosis, and avoid unwanted outcomes. Besides glucocorticoids, traditional immunosuppressants (i.e. cyclosporine, mycophenolate mofetil) and intravenous immunoglobulins, new therapies are emerging and promising for the treatment of intractable SLE-ITP, such as thrombopoietin receptor agonists (TPO-RAs), platelet desialylation inhibitors(i.e. oseltamivir), B-cell targeting therapy(i.e. rituximab, belimumab), neonatal Fc receptor(FcRn) inhibitor, spleen tyrosine kinase(Syk) inhibitor and Bruton tyrosine kinase(BTK) inhibitor et al., although more rigorous randomized controlled trials are needed to substantiate their efficacy. In this review, we update our current knowledge on the pathogenesis and treatment of SLE-ITP.