Hirsutide

Introduction:Hirsutine and hirsuteine are the main pharmacological activity ingredients of Uncaria rhynchophylla (UR), playing an important role in treating mental and cardiovascular diseases, such as Alzheimer's disease, hypertension, Parkinson's disease, potential anti-cancer activities and so on.Objective:To develop a cyclodextrin-modified micellar electrokinetic capillary chromatography (CD-MEKC) method for the simultaneous separation and determination of hirsutine and hirsuteine from UR and its formulations.Methodology:The optimal method was developed by investigating influences of significant factors on the separation, and this method was successfully applied for the determination of hirsutine and hirsuteine in UR and its formulations.Results:The optimal background electrolyte (BGE) consisted of 40 mM sodium dihydrogen phosphate (pH 7.0), 150 mM 2,6-dimethyl-β-cyclodextrin (DM-β-CD), 3 mM mono-(6-ethylenediamine-6-deoxy)-β-cyclodextrin (ED-β-CD), and 30 mM sodium cholate (SC). Under these conditions, hirsutine and hirsuteine were successfully separated within 13 min at the separation voltage of 15 kV, temperature of 25°C and the detection wavelength of 224 nm. For the analytes, linear calibration curves were performed within the range 5.0-160.0 μg/mL. The limit of detection (LOD, S/N = 3) and the limit of quantitation (LOQ, S/N = 10) were 0.41, 1.42 μg/mL for hirsutine and 0.60, 2.17 μg/mL for hirsuteine, respectively. The recoveries of three samples were from 97.9% to 102.3%.Conclusion:The method was successfully applied to the determination of hirsutine and hirsuteine in UR and its formulations. Meanwhile, it provides an effective reference of the quality control of UR and its formulations.

Background:Thrombocytopenia (TP) remains a challenge in clinical hematology. TP may have serious consequences, such as recurrent skin and mucosal bleeding and increased risk of intracranial and internal organ hemorrhage. However, effective and safe therapeutic drugs for the long-term management of TP are still lacking.Purpose:This study aimed to identify more effective active compounds for TP therapy.Methods:Liquid chromatography-mass spectrometry-nuclear magnetic resonance analysis was used to confirm the medicinal species and chemical structure of Hirsutine (HS). The proliferation of HS was examined by Cell Counting Kit (CCK-8) assay on cells lines. The effect of HS on megakaryocyte differentiation was analyzed by evaluating the expression of CD41, CD42b, and DNA ploidy via flow cytometry (FCM). The morphology of megakaryocytes and intermediate cells was observed using an optical microscope. K562 cells were then stained with Giemsa and benzidine. qRT-PCR was used to examine the mRNA expression of GATA-1, GATA-2, FOG-1, TAL-1, RUNX-1, NF-E2, and KLF-1 in K562 cells. Protein levels of the transcription factors were analyzed by western blotting. An MEK inhibitor was used to verify the relationship between the MEK/ERK signaling pathway and CD41/CD42b (FCM), FOG-1, and TAL-1. The Kunming thrombocytopenia mouse model was established by X-ray irradiation (4 Gy) and used to test HS activity and related hematopoietic organ index in vivo. Finally, computer simulations of molecular docking were used to predict the binding energies between HS-MEK and HS-ERK.Results:We preliminarily identified HS by screening a plant-sourced compound library for natural compounds with megakaryocytic differentiation and maturation (MKD/MKM)-promoting activity. We found that HS not only enhanced MKD/MKM of K562 and Meg01 cells, but also suppressed the decline of peripheral platelet levels in X-ray-induced myelosuppressive mice. In addition, HS promoted MKD via activation of MEK-ERK-FOG1/TAL1 signaling, which may be the key molecular mechanism of HS action in TP treatment. Molecular docking simulations further verified that HS targets the signaling protein MEK with high-affinity.Conclusion:In this study, we report for the first time that hirsutine boosts MKD/MKM through the MEK/ERK/FOG1/TAL1 signaling pathway and thus represents a promising treatment option for TP.

Nuclear factor-κB (NF-κB) activation has been implicated not only in carcinogenesis but also in cancer cell invasion and metastatic process; therefore, targeting the NF-κB pathway is an attractive strategy for controlling meta-stasis. Amongst 56 chemically defined compounds derived from natural products, we have identified a new phytochemical compound Hirsutine, which strongly suppresses NF-κB activity in murine 4T1 breast cancer cells. In accordance with the NF-κB inhibition, Hirsutine reduced the metastatic potential of 4T1 cells, as seen in the inhibition of the migration and invasion capacity of 4T1 cells. Hirsutine further inhibited the constitutive expression of MMP-2 and MMP-9 in 4T1 cells, and reduced the in vivo lung metastatic potential of 4T1 cells in the experimental model. Given that the migration of human breast cancer cells was also inhibited, our present study implies that Hirsutine is an attractive phytochemical compound for reducing metastasis potential of cancer cells by regulating tumor-promoting NF-κB activity.