Stachydrine hydrochloride ameliorates cardiac hypertrophy through CaMKII/HDAC4/MEF2C signal pathway.

Stachydrine hydrochloride (Sta), an activated alkaloid, is isolated from traditional Chinese medicine Yimucao. In previous studies, the cardioprotective effects of Sta were found in our laboratory. However, the underling mechanisms of Sta is not fully elucidated. The aim of this study was to provide a detailed account of the anti-hypertrophic effects of Sta on transcriptional regulation. In vivo, C57BL/6J mice were subjected to transverse aortic constriction (TAC) and were orally treated with Sta. Morphological assessments, echocardiographic parameters, histological analyses and immunofluorescence were used to evaluate cardiac hypertrophy. In vitro, cardiomyocytes were stimulated by phenylephrine (PE), and cell surface and hypertrophy markers were tested by immunofluorescence and real-time polymerase chain reaction (RT-PCR). Moreover, western blotting, RT-PCR and luciferase reporter genes were used to assess the expression of proteins, mRNA and the activity of the CaMKII/HDAC4/MEF2C signal pathway in vivo and in vitro. We found that Sta blocked cardiac hypertrophy induced by pressure overload. We also demonstrated that Sta inhibited nuclear export or promoted nuclear import of HDAC4 through regulation of p-CaMKII, and it further improved the repression of MEF2C. Taken together, our findings demonstrated that Sta ameliorates cardiac hypertrophy through CaMKII/HDAC4/MEF2C signal pathway.

Trans-cinnamaldehyde suppresses microtubule detyrosination and alleviates cardiac hypertrophy.

BACKGROUND: Trans-cinnamaldehyde (TCA) is a main compound of Cinnamomum cassia, used in traditional Chinese medicine to treat many ailments. Increasing evidence has demonstrated the therapeutic effects of TCA in cardiovascular diseases. PURPOSE: The present study aimed to determine whether TCA exerts antihypertrophic effects in vitro and in vivo and to elucidate the underlying mechanisms of these effects. METHODS: Neonatal rat cardiac myocytes (NRCMs) and adult mouse cardiac myocytes (AMCMs) were treated with 50 µΜ phenylephrine (PE) for 48 h. Tubulin detyrosination, store-operated Ca2+ entry (SOCE), stromal interaction molecule-1 (STIM1)/Orai1 translocation, and calcineurin/nuclear factor of activated T-cells (NFAT) signaling pathways were analyzed in NRCMs. Meanwhile, tubulin detyrosination, junctophilin-2, T-tubule distribution pattern, Ca2+ handling, and sarcomere shortening were observed in AMCMs. Male C57BL/6 mice were stimulated with PE (70 mg/kg per day) with or without TCA treatment for 2 weeks. Cardiac hypertrophy and tubulin detyrosination were also assessed. RESULTS: TCA was confirmed to alleviate cardiac hypertrophy induced by PE stimulation in vitro and in vivo. PE-induced cardiac hypertrophy was associated with excessive tubulin detyrosination and overexpression of vasohibin 1 (VASH1) and small vasohibin binding protein (SVBP), two key proteins responsible for tubulin detyrosination. These effects were largely blocked by TCA administration. PE treatment also enhanced SOCE with massive translocation of STIM1 and Orai1, Ca2+ mishandling, reduced sarcomere shortening, junctophilin-2, and T-tubule redistribution, all of which were significantly ameliorated by TCA administration. CONCLUSION: Our study indicated that the therapeutic effects of TCA against cardiac hypertrophy may be associated with its ability to reduce tubulin detyrosination.

Treatment of Masked Hypertension with a Chinese Herbal Formula: A Randomized, Placebo-Controlled Trial.

BACKGROUND: Masked hypertension is associated with adverse cardiovascular outcomes. Nonetheless, no randomized controlled trials exist in the treatment of masked hypertension. The aim of this randomized, placebo-controlled trial was to investigate the efficacy and safety of blood pressure (BP)-lowering treatment with a Chinese herbal formula, gastrodia-uncaria granules, in patients with masked hypertension. METHODS: Patients with an office BP of <140/90 mm Hg and daytime ambulatory BP of 135 to 150 mm Hg systolic or 85 to 95 mm Hg diastolic were randomly assigned 1:1 to the treatment of gastrodia-uncaria granules or placebo 5 to 10 g twice daily for 4 weeks. The primary efficacy variable was the change in daytime ambulatory BP. RESULTS: At baseline, office and daytime BP of the 251 participants (mean age, 50.4 years; 53.4% men; mean body mass index 24.5 kg/m2; and 2.8%, 1.6%, and 30.7% with cardiovascular disease, diabetes, and smoking, respectively) averaged 129/82 and 135/89 mm Hg, respectively. In the intention-to-treat analysis, daytime systolic/diastolic BP was reduced by 5.44/3.39 and 2.91/1.60 mm Hg in the gastrodia-uncaria granules and placebo groups, respectively. The between-group difference in BP reductions was significant for the daytime (2.52/1.79 mm Hg; P≤0.025) and 24-hour BP (2.33/1.49 mm Hg; P≤0.012), but not for the clinic and nighttime BPs (P≥0.162). The per-protocol analysis in 229 patients produced similar results. Only 1 adverse event (sleepiness during the day) was reported, and no serious adverse event occurred. CONCLUSIONS: BP-lowering treatment with Chinese traditional medicine gastrodia-uncaria granules is efficacious for patients with masked hypertension. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02156024.

Stachydrine hydrochloride alleviates pressure overload-induced heart failure and calcium mishandling on mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese medicine Leonurus japonicus Houtt. has a long history in the treatment of cardiovascular diseases. Stachydrine hydrochloride, the main bioactive ingredient extracted from Leonurus japonicus Houtt., has been shown to have cardioprotective effects. However, the underlying mechanisms of stachydrine hydrochloride haven't been comprehensively studied so far. AIM OF THE STUDY: The aim of this study was to investigate the protective role of stachydrine hydrochloride in heart failure and elucidate its possible mechanisms of action. MATERIALS AND METHODS: In vivo, transverse aorta constriction was carried out in C57BL/6J mice, and thereafter, 7.2 mg/kg telmisartan (a selective AT1R antagonist as positive control) and 12 mg/kg stachydrine hydrochloride was administered daily intragastrically for 4 weeks. Cardiac function was evaluated by assessing morphological changes as well as echocardiographic and haemodynamic parameters. In vitro, neonatal rat cardiomyocytes or adult mice cardiomyocytes were treated with stachydrine hydrochloride and challenged with phenylephrine (α-AR agonist). Ventricular myocytes were isolated from the hearts of C57BL/6J mice by Langendorff crossflow perfusion system. Intracellular calcium was measured by an ion imaging system. The length and movement of sarcomere were traced to evaluate the systolic and diastolic function of single myocardial cells. RESULTS: Stachydrine hydrochloride improved the cardiac function and calcium transient amplitudes, and inhibited the SR leakage and the amount of sparks in cardiac myocytes isolated from TAC mice. We also demonstrated that stachydrine hydrochloride could ameliorated phenylephrine-induced enhance in sarcomere contraction, calcium transients and calcium sparks. Moreover, our data shown that stachydrine hydrochloride blocked the hyper-phosphorylation of CaMKII, RyR2, PLN, and prevented the disassociation of FKBP12.6 from RyR2. CONCLUSION: Our results suggest that stachydrine hydrochloride exerts beneficial therapeutic effects against heart failure. These cardioprotective effects may be associated with the regulation of calcium handling by stachydrine hydrochloride through inhibiting the hyper-phosphorylation of CaMKII.

Effects of stachydrine on norepinephrine-induced neonatal rat cardiac myocytes hypertrophy and intracellular calcium transients.

BACKGROUND: Leonurus heterophyllus sweet has been suggested to have cardioprotective effects against heart diseases, including ischemic diseases and ventricular remodeling. However, the active ingredients of the herb and the underlying mechanisms are poorly understood. The aim of the present study was to investigate the effects of stachydrine (STA), a major constituent of Leonurus heterophyllus sweet, on norepinephrine (NE) induced hypertrophy and the changes of calcium transients in neonatal rat cardiomyocytes. METHODS: Ventricular myocytes from 1-day-old Wistar rats were isolated and cultured in DMEM/F12 with 1 µmol/L norepinephrine in the presence or absence of 10 µmol/L STA for 72 h. Cardiomyocytes hypertrophy was evaluated by cell surface area, total protein/DNA content, ß/α-MHC mRNA ratio. While calcium handling function was evaluated by Ca2+-transient amplitude and decay, SERCA2a activity and expression, PLN expression and phosphorylation. ß1-adrenergic receptor system activation was evaluated by the content of cAMP and the activation of PKA. RESULTS: NE treatment increases the cell surface area, protein synthesis, the expression level of ß-MHC and ß/α-MHC ratio. These effects were attenuated by STA. NE-induced hypertrophy was associated with increased Ca2+-transient amplitude, accelerated decay of the Ca2+-transient, increased phospholamban expression, hyper-phosphorylation at both the serine-16 and threonine-17 residues, increased intracellular cAMP level, and PKA overactivation. All of which were significantly inhibited by STA. CONCLUSION: These data suggest that STA attenuates norepinephrine-induced cardiomyocyte hypertrophy and has potential protective effects against ß-adrenergic receptor induced Ca2+ mishandling.