Janus kinase/signal transducer and activator of transcription inhibitors enhance the protective effect mediated by tanshinone IIA from hypoxic/ischemic injury in cardiac myocytes

Targeting the JAK2/STAT3 signaling pathway with natural plants and phytochemical ingredients: A novel therapeutic method for combatting cardiovascular diseases

The aim of this article is to introduce the roles and mechanisms of the JAK2/STAT3 pathway in various cardiovascular diseases, such as myocardial fibrosis, cardiac hypertrophy, atherosclerosis, myocardial infarction, and myocardial ischemiareperfusion. In addition, the effects of phytochemical ingredients and different natural plants, mainly traditional Chinese medicines, on the regulation of different cardiovascular diseases via the JAK2/STAT3 pathway are discussed. Surprisingly, the JAK2 pathway has dual roles in different cardiovascular diseases. Future research should focus on the dual regulatory effects of different phytochemical ingredients and natural plants on JAK2 to pave the way for their use in clinical trials.

Combination therapy of tanshinone IIA and puerarin for pulmonary fibrosis via targeting IL6-JAK2-STAT3/STAT1 signaling pathways

Efficient therapy of idiopathic pulmonary fibrosis (IPF) is still a major challenge. The current studies with single-target drug therapy are the pessimistic approaches due to the complex characteristics of IPF. Here, a combination therapy of Tanshinone IIA and Puerarin for IPF was proposed to alleviate IPF due to their antiinflammatory and anti-fibrotic effects. In vivo, the combination therapy could significantly attenuate the area of ground glass opacification that was presented by 85% percentile density score of the micro-CT images when compared to single conditions. In addition, the combination therapy enormously improved the survival rate and alleviated pathological changes in bleomycin (BLM)-induced IPF mice. By using a wide spectrum of infiltration biomarkers in immunofluorescence assay in pathological sections, we demonstrate that fewer IL6 related macrophage infiltration and fibrosis area after this combination therapy, and further proved that IL6-JAK2-STAT3/STAT1 is the key mechanism of the combination therapy. In vitro, combination therapy markedly inhibited the fibroblasts activation and migration which was induced by TGF-β1 or/and IL6 through JAK2-STAT3/STAT1 signaling pathway. This study demonstrated that combination therapeutic effect of TanIIA and Pue on IPF may be related to the reduced inflammatory response targeting IL6, which could be an optimistic and effective approach for IPF.

Tanshinones: An Update in the Medicinal Chemistry in Recent 5 Years

Tanshinones are an important type of natural products isolated from Salvia miltiorrhiza Bunge with various bioactivities. Tanshinone IIa, cryptotanshinone and tanshinone I are three kinds of tanshinones which have been widely investigated. Particularly, sodium tanshinone IIa sulfonate is a water-soluble derivative of tanshinone IIa and it is used in clinical in China for treating cardiovascular diseases. In recent years, there are increasing interests in the investigation of tanshinones derivatives in various diseases. This article presents a review of the anti-atherosclerotic effects, cardioprotective effects, anticancer activities, antibacterial activities and antiviral activities of tanshinones and structural modification work in recent years.

Naringin attenuates high glucose-induced injuries and inflammation by modulating the leptin-JAK2/STAT3 pathway in H9c2 cardiac cells

INTRODUCTION

Our previous study showed that naringin (NRG) protects cardiomyocytes against high glucose (HG)-induced injuries by inhibiting p38 mitogen-activated protein kinase (MAPK). Leptin induces hypertrophy in rat cardiomyocytes via p38/MAPK activation. The present study aimed to test the hypothesis that leptin-Janus kinase 2 (JAK2)/signal transducers and activators of transcription 3 (STAT3), which are responsible for leptin's functions, are involved in HG-induced injuries and cardioprotective effects of NRG in cardiomyocytes.

MATERIAL AND METHODS

H9c2 cells were exposed to HG for 24 h to establish a cardiomyocyte injury model. Cells were pretreated with NRG and other drugs before exposure to HG. Protein expression was measured by western blot analysis. Cell viability was detected by Cell Counting Kit-8 assay. Apoptotic cells were assessed by Hoechst 33258 staining assay. Intracellular reactive oxygen species levels were determined by dichlorofluorescein diacetate staining. Mitochondrial membrane potential was evaluated using JC-1. An enzyme-linked immunosorbent assay was performed to determine the inflammatory cytokines.

RESULTS

NRG significantly attenuated HG-induced increases in leptin and Ob-R expression. Pretreatment with either a leptin antagonist (LA) or NRG markedly ameliorated HG-induced elevation of phosphorylated (p)-JAK2 and p-STAT3, respectively. Pretreatment with NRG, LA, Ob-R antagonist, or AG490 clearly alleviated HG-induced injuries and inflammation.

CONCLUSIONS

This study provides new evidence of the NRG protective effects of H9c2 cells against HG-induced injuries possibly via modulation of the leptin-JAK2/STAT3 pathway.

Salvia miltiorrhizaBurge (Danshen): a golden herbal medicine in cardiovascular therapeutics

Salvia miltiorrhiza Burge (Danshen) is an eminent medicinal herb that possesses broad cardiovascular and cerebrovascular protective actions and has been used in Asian countries for many centuries. Accumulating evidence suggests that Danshen and its components prevent vascular diseases, in particular, atherosclerosis and cardiac diseases, including myocardial infarction, myocardial ischemia/reperfusion injury, arrhythmia, cardiac hypertrophy and cardiac fibrosis. The published literature indicates that lipophilic constituents (tanshinone I, tanshinone IIa, tanshinone IIb, cryptotanshinone, dihydrotanshinone, etc) as well as hydrophilic constituents (danshensu, salvianolic acid A and B, protocatechuic aldehyde, etc) contribute to the cardiovascular protective actions of Danshen, suggesting a potential synergism among these constituents. Herein, we provide a systematic up-to-date review on the cardiovascular actions and therapeutic potential of major pharmacologically active constituents of Danshen. These bioactive compounds will serve as excellent drug candidates in small-molecule cardiovascular drug discovery. This article also provides a scientific rationale for understanding the traditional use of Danshen in cardiovascular therapeutics.

Tanshinone IIA ameliorates apoptosis of cardiomyocytes induced by endoplasmic reticulum stress

The fat-soluble diterpenoids tanshinone IIA (TSA) is the major active element of Danshen, which has widespread cardioprotective effect. However, the mechanism of its beneficial effect on cardiomyocytes has not been fully investigated. Here, we aim to demonstrate that TSA ameliorates apoptosis of cardiomyocytes activated by endoplasmic reticulum stress (ERS). Primary cultures of neonatal rat cardiomyocytes are used, in which ERS-mediated apoptosis is induced by tunicamycin (Tm). Apoptosis of cardiomyocytes are detected by Hoechst staining and caspase 3 activity analysis. Protein expression of ERS markers are detected by Western blot, and level of miroRNA-133 (miR-133) is detected by real-time polymerase chain reaction. Tm treatment significantly triggers the apoptosis and ERS of cardiomyocytes. TSA dramatically ameliorates apoptosis and ERS of cardiomyocytes induced by Tm. Interestingly, level of miR-133 is reduced by Tm treatment, which is reversed by TSA. The cardioprotective effect of TSA on apoptosis and ERS of cardiomyocytes is blocked by anti-miR-133. These results suggest that TSA protects cardiomyocytes through ameliorated ERS-mediated apoptosis, which may be resulted from upregulation of miR-133.

Molecular Mechanisms of Cardioprotective Actions of Tanshinones

Tanshinones are lipophilic compounds derived fromSalvia miltiorrhiza(Danshen) that has been widely used to treat coronary heart diseases in China. The cardioprotective actions of tanshinones have been extensively studied in various models of myocardial infarction, cardiac ischemia reperfusion injury, cardiac hypertrophy, atherosclerosis, hypoxia, and cardiomyopathy. This review outlines the recent development in understanding the molecular mechanisms and signaling pathways involved in the cardioprotective actions of tanshinones, in particular on mitochondrial apoptosis, calcium, nitric oxide, ROS, TNF-α, PKC, PI3K/Akt, IKK/NF-κB, and TGF-β1/Smad mechanisms, which highlights the potential of these compounds as therapeutic agents for treating cardiovascular diseases.