Central inhibition prevents the in vivo acute toxicity of harmine in mice

Harmine promotes megakaryocyte differentiation and thrombopoiesis by activating the Rac1/Cdc42/JNK pathway through a potential target of 5-HTR2A

Harmine (HM), a β-carboline alkaloid extracted from plants, is a crucial component of traditional Chinese medicine (TCM) known for its diverse pharmacological activities. Thrombocytopenia, a common and challenging hematological disorder, often coexists with serious illnesses. Previous research has shown a correlation between HM and thrombocytopenia, but the mechanism needs further elucidation. The aim of this study was to clarify the mechanisms underlying the effects of HM on thrombocytopenia and to develop new therapeutic strategies. Flow cytometry, Giemsa staining, and Phalloidin staining were used to assess HM's impact on Meg-01 and HEL cell differentiation and maturation in vitro. A radiation-induced thrombocytopenic mouse model was employed to evaluate HM's effect on platelet production in vivo. Network pharmacology, molecular docking, and protein blotting were utilized to investigate HM's targets and mechanisms. The results demonstrated that HM dose-dependently promoted Meg-01 and HEL cell differentiation and maturation in vitro and restored platelet levels in irradiated mice in vivo. Subsequently, HM was found to be involved in the biological process of platelet production by upregulating the expressions of Rac1, Cdc42, JNK, and 5-HTR2A. Furthermore, the targeting of HM to 5-HTR2A and its correlation with downstream Rac1/Cdc42/JNK were also confirmed. In conclusion, HM regulates megakaryocyte differentiation and thrombopoiesis through the 5-HTR2A and Rac1/Cdc42/JNK pathways, providing a potential treatment strategy for thrombocytopenia.

Identification of functional biomarkers of Peganum harmala and Hypericum perforatum using PCA-constructed secondary metabolite maps

Peganum harmala L. (P. harmala), also known as Espand, Harmel, or Syrian rue, and Hypericum perforatum L. (H. perforatum), commonly known as St. John's wort, are two of the widely cultivated industrial crops and used worldwide in antihepatoma-related products. However, their main functional substances are still not clear, thus impeding the efficacy evaluations and quality controls of relative products around the world. In this work, the anti-hepatoma biomarkers of P. harmala and H. perforatum were clarified through the development of principal components analysis (PCA)-HPLC secondary metabolite mapping models. The chemical fingerprints of plant extracts were profiled by HPLC and then mapped to produce the secondary metabolite models using PCA. The models correlated the chemical information with the anti-hepatoma activities of plant extracts, thus indicating the functional inhibitors of P. harmala and H. perforatum against hepatoma cells. The activities of the identified compounds were validated by cytotoxic and apoptotic assays. The major inhibitors of P. harmala and H. perforatum against human hepatoma were determined to be harmine and quercetin, respectively. The IC50 values and the induced apoptotic rate of harmine on HepG2 cells were 20.7 ± 2.8 μM and 46.7 ± 3.5 %, respectively. The IC50 values and the induced apoptotic rate of quercetin on HepG2 cells were 49.5 ± 6.6 μM and 38.7 ± 2.6 %, respectively. In conclusion, the results significantly expanded the understanding of the biochemical foundations of P. harmala and H. perforatum, thus evidently supporting their current applications around the world. Moreover, harmine and quercetin could be used as biomarkers to evaluate the efficacy and quality of related products of industrial crops in therapeutic and health-improving applications.