Cardiac hypertrophy after myocardial infarction (MI) is an independent risk factor for heart failure. Regression of cardiac hypertrophy has emerged as a promising strategy in the treatment of MI patients. Here, we have been suggested that heat-shock transcription factor 1 (HSF1) is a novel repressor of ischaemia-induced cardiac hypertrophy. Ligation of left anterior descending coronary was used to produce MI in HSF1-deficient heterozygote (KO), HSF1 transgenic (TG) mice and their wild-type (WT) littermates, respectively. Neonatal rat cardiomyocytes (NRCMs) were treated by hypoxia to mimic MI in vitro. The HSF1 phosphorylation was significantly reduced in the infarct border zone of mouse left ventricles (LVs) 1 week after MI and in the hypoxia-treated NRCMs. HSF1 KO mice showed more significant maladaptive cardiac hypertrophy and deteriorated cardiac dysfunction 1 week after MI compared to WT MI mice. Deficiency of HSF1 by siRNA transfection notably increased the hypoxia-induced myocardial hypertrophy in NRCMs. Mechanistically, Janus kinase 2 (JAK2) and its effector, signal transducer and activator of transcription 3 (STAT3) were found to be significantly increased in the LV infarct border zone of WT mice after MI as well as the NRCMs treated by hypoxia. These alterations were more significant in HSF1 KO mice and NRCMs transfected with HSF1 SiRNA. Inversely, HSF1 TG mice showed significantly ameliorated cardiac hypertrophy and heart failure 1 week after LAD ligation compared to their WT littermates. Our data collectively demonstrated that HSF1 is critically involved in the pathological cardiac hypertrophy after MI via modulating JAK2/STAT3 signalling and may constitute a potential therapeutic target for MI patients.

Optimal timing of cell therapy for myocardial infarction (MI) appears during 5 to 14 days after the infarction. However, the potential mechanism requires further investigation. This work aimed to verify the hypothesis that myocardial stiffness within a propitious time frame might provide a most beneficial physical condition for cell lineage specification in favour of cardiac repair. Serum vascular endothelial growth factor (VEGF) levels and myocardial stiffness of MI mice were consecutively detected. Isolated bone marrow mononuclear cells (BMMNCs) were injected into infarction zone at distinct time-points and cardiac function were measured 2 months after infarction. Polyacrylamide gel substrates with varied stiffness were used to mechanically mimic the infarcted myocardium. BMMNCs were plated on the flexible culture substrates under different concentrations of VEGF. Endothelial progenitor lineage commitment of BMMNCs was verified by immunofluorescent technique and flow cytometry. Our results demonstrated that the optimal timing in terms of improvement of cardiac function occurred during 7 to 14 days after MI, which was consistent with maximized capillary density at this time domains, but not with peak VEGF concentration. Percentage of double-positive cells for DiI-labelled acetylated low-density lipoprotein uptake and fluorescein isothiocyanate (FITC)-UEA-1 (ulex europaeus agglutinin I lectin) binding had no significant differences among the tissue-like stiffness in high concentration VEGF. With the decrease of VEGF concentration, the benefit of 42 kPa stiffness, corresponding to infarcted myocardium at days 7 to 14, gradually occurred and peaked when it was removed from culture medium. Likewise, combined expressions of VEGFR2(+) , CD133(+) and CD45(-) remained the highest level on 42 kPa substrate in conditions of lower concentration VEGF. In conclusion, the optimal efficacy of BMMNCs therapy at 7 to 14 days after MI might result from non-VEGF dependent angiogenesis, and myocardial stiffness at this time domains was more suitable for endothelial progenitor lineage specification of BMMNCs. The results here highlight the need for greater attention to mechanical microenvironments in cell culture and cell therapy.

It is well established that cancer cells depend upon aerobic glycolysis to provide the energy they need to survive and proliferate. However, anti-glycolytic agents have yielded few positive results in human patients, in part due to dose-limiting side effects. Here, we discovered the unexpected anti-cancer efficacy of Polydatin (PD) combined with 2-deoxy-D-glucose (2-DG), which is a compound that inhibits glycolysis. We demonstrated in two breast cell lines (MCF-7 and 4T1) that combination treatment with PD and 2-DG induced cell apoptosis and inhibited cell proliferation, migration and invasion. Furthermore, we determined the mechanism of PD in synergy with 2-DG, which decreased the intracellular reactive oxygen (ROS) levels and suppressed the PI3K/AKT pathway. In addition, the combined treatment inhibited the glycolytic phenotype through reducing the expression of HK2. HK2 deletion in breast cancer cells thus improved the anti-cancer activity of 2-DG. The combination treatment also resulted in significant tumour regression in the absence of significant morphologic changes in the heart, liver or kidney in vivo. In summary, our study demonstrates that PD synergised with 2-DG to enhance its anti-cancer efficacy by inhibiting the ROS/PI3K/AKT/HIF-1α/HK2 signalling axis, providing a potential anti-cancer strategy.

Exercise training is believed to have a positive effect on cardiac hypertrophy after hypertension. However, its mechanism is still not fully understood. Herein, our findings suggest that heat shock transcription factor 1 (HSF1) improves exercise-initiated myocardial angiogenesis after pressure overload. A sustained narrowing of the diagonal aorta (TAC) and moderately- intense exercise training protocol were imposed on HSF1 heterozygote (KO) and their littermate wild-type (WT) male mice. After two months, the cardiac function was assessed using the adaptive responses to exercise training, or TAC, or both of them such as catheterization and echocardiography. The HE stains assessed the area of myocyte cross-sectional. The Western blot and real-time PCR measured the levels of expression for heat shock factor 1 (HSF1), vascular endothelial growth factor (VEGF) and hypoxia inducible factor-1 alpha (HIF-1α) in cardiac tissues. The anti-CD31 antibody immunohistochemical staining was done to examine how exercise training influenced cardiac ontogeny. The outcome illustrated that exercise training significantly improved the cardiac ontogeny in TAC mice, which was convoyed by elevated levels of expression for VEGF and HIF-1α and preserved the heart microvascular density. More importantly, HSF1 deficiency impaired these effects induced by exercise training in TAC mice. In conclusion, exercise training encourages cardiac ontogeny by means of HSF1 activation and successive HIF-1α/VEGF up-regulation in endothelial cells during continued pressure overload.

Cardiac fibrosis critically injured the cardiac structure and function of the hypertensive patients. However, the anti-fibrotic strategy is still far from satisfaction. This study aims to determine the effect and mechanism of Pirfenidone (PFD), an anti-lung fibrosis medicine, in the treatment of cardiac fibrosis and heart failure induced by pressure overload. Male C57BL/6 mice were subjected to thoracic aorta constriction (TAC) or sham surgery with the vehicle, PFD (300 mg/kg/day) or Captopril (CAP, 20 mg/kg/day). After 8 weeks of surgery, mice were tested by echocardiography, and then sacrificed followed by morphological and molecular biological analysis. Compared to the sham mice, TAC mice showed a remarkable cardiac hypertrophy, interstitial and perivascular fibrosis and resultant heart failure, which were reversed by PFD and CAP significantly. The enhanced cardiac expression of TGF-β1 and phosphorylation of Smad3 in TAC mice were both restrained by PFD. Cardiac fibroblasts isolated from adult C57BL/6 mice were treated by Angiotensin II, which led to significant increases in cellular proliferation and levels of α-SMA, vimentin, TGF-β1 and phosphorylated TGF-β receptor and Smad3. These changes were markedly inhibited by pre-treatment of PFD. Collectively, PFD attenuates myocardial fibrosis and dysfunction induced by pressure overload via inhibiting the activation of TGF-β1/Smad3 signalling pathway.

Alpinetin, the main active ingredient in the Chinese medicinal herb Alpinia katsumadai Hayata, has been found to have anticancer activity. However, the therapeutic efficacy of signalling cascades modulated by alpinetin remains unknown. Here, we showed that alpinetin provoked mitochondria-associated apoptosis in a dose-dependent manner in breast cancer cells. Mechanistic investigations revealed that alpinetin dampens hypoxia-inducible factor-1α (HIF-1α) signalling due to a lack of NF-κB activation through reduced mitochondrial reactive oxygen species (ROS) production, decreasing HIF-1α transcription. In vivo, we also found alpinetin led to significant tumour regression by inhibiting NF-κB pathway. Overall, our work uncovers a ROS/NF-κB/HIF-1α axis-dependent mechanism underlying the anticancer effects of alpinetin and suggests that alpinetin could act as a novel therapeutic agent against breast cancer.

Adiponectin is an adipocyte-derived hormone, which is closely associated with the development of Alzheimer's disease (AD) and has potential preventive and therapeutic significance. In the present study, we explored the relationship between adiponectin and circadian rhythm disorder in AD, the effect of adiponectin on the abnormal expression of Bmal1 mRNA/protein induced by amyloid-β protein 31-35 (Aβ31-35), and the underlying mechanism of action. We found that adiponectin-knockout mice exhibited amyloid-β deposition, circadian rhythm disorders and abnormal expression of Bmal1. Adiponectin ameliorated the abnormal expression of the Bmal1 mRNA/protein caused by Aβ31-35 by inhibiting the activity of glycogen synthase kinase 3β (GSK3β). These results suggest that adiponectin deficiency could induce circadian rhythm disorders and abnormal expression of the Bmal1 mRNA/protein, whilst exogenous administration of adiponectin may improve Aβ31-35-induced abnormal expression of Bmal1 by inhibiting the activity of GSK3β, thus providing a novel idea for the treatment of AD.

Staphylococcus aureus (S. aureus) causes severe inflammation in various infectious diseases, leading to high mortality. The clinical application of antibiotics has gained a significant curative effect. However, it has led to the emergence of various resistant bacteria. Therefore, in this study, we investigated the protective effect of polydatin (PD), a traditional Chinese medicine extract, on S. aureus lipoteichoic acid (LTA)-induced injury in vitro and in vivo. First, a significant improvement in the pathological conditions of PD in vivo was observed, suggesting that PD had a certain protective effect on LTA-induced injury in a mouse model. To further explore the underlying mechanisms of this protective effect of PD, LTA-induced murine macrophages were used in this study. The results have shown that PD could reduce the NF-κB p65, and IκBα phosphorylation levels increased by LTA, resulting in a decrease in the transcription of pro-inflammatory factors, such as TNF-α, IL-1β and IL-6. However, LTA can not only activate NF-κB through the recognition of TLR2 but also increase the level of intracellular reactive oxygen species (ROS), thereby activating NF-κB signalling. We also detected high levels of ROS that activate caspases 9 and 3 to induce apoptosis. In addition, using a specific NF-κB inhibitor that could attenuate apoptosis, namely NF-κB p65, acted as a pro-apoptotic transcription factor in LTA-induced murine macrophages. However, PD could inhibit the generation of ROS and NF-κB p65 activation, suggesting that PD suppressed LTA-induced injury by attenuating ROS generation and TLR2-NFκB signalling.

Cardiomyocytes autophagy is essential for maintaining cardiac function. Our previous studies have found that β1 -adrenergic receptor autoantibody (β1 -AA) induced the decreased myocardial autophagic flux, which resulted in cardiomyocyte death and cardiac dysfunction. And other studies demonstrated that β1 -AA induced the decrease of AMPK phosphorylation, the key hub of autophagy pathway, while adiponectin up-regulated autophagic flux mediated by AMPK. However, it is not clear whether adiponectin improves the inhibition of myocardial autophagic flux induced by β1 -AA by up-regulating the level of AMPK phosphorylation. In this study, it has been confirmed that β1 -AA induced the decrease of AMPK phosphorylation level in both vivo and vitro. Moreover, pretreatment of cardiomyocytes with AMPK inhibitor Compound C could further reduce the autophagic flux induced by β1 -AA. Adiponectin deficiency could aggravate the decrease of myocardial AMPK phosphorylation level, autophagic flux and cardiac function induced by β1 -AA. Further, exogenous adiponectin could reverse the decline of AMPK phosphorylation level and autophagic flux induced by β1 -AA and even reduce cardiomyocyte death. While pretreated with the Compound C, the adiponectin treatment did not improve the decreased autophagosome formation, but still improved the decreased autophagosome clearance induced by β1 -AA in cardiomyocytes. This study is the first time to confirm that β1 -AA could inhibit myocardial autophagic flux by down-regulating AMPK phosphorylation level. Adiponectin could improve the inhibition of myocardial autophagic flux induced by β1 -AA partly dependent on AMPK, so as to provide an experimental basis for the treatment of patients with β1 -AA-positive cardiac dysfunction.

Cardiac conduction disease (CCD) is a serious disorder and the leading cause of mortality worldwide. It is characterized by arrhythmia, syncope or even sudden cardiac death caused by the dysfunction of cardiac voltage-gated channel. Previous study has demonstrated that mutations in genes encoding voltage-gated channel and related proteins were the crucial genetic lesion of CCD. In this study, we employed whole-exome sequencing to explore the potential causative genes in a Chinese family with ventricular tachycardia and syncope. A novel nonsense mutation (c.565C>T/p.R189X) of glycerol-3-phosphate dehydrogenase-like (GPD1L) was identified and co-segregated with the affected family members. GPD1L is a crucial interacting protein of SCN5A, a gene encoded sodium channel α-subunit Nav 1.5 and mainly associated with Brugada syndrome (BrS). The novel mutation (c.565C>T/p.R189X) may result in a premature stop codon at position 189 in exon 4 of the GPD1L gene and lead to functional haploinsufficiency of GPD1L due to mRNA carrying this mutation will be degraded by nonsense-mediated mRNA decay, which has been confirmed by Western blot in HEK293 cells transfected HIS-GPD1L plasmid. The levels of GPD1L decreasing may disturb the function of Nav 1.5 and induce arrhythmia and syncope in the end. In conclusion, our study not only further supported the important role of GPD1L in CCD, but also expanded the spectrum of GPD1L mutations and will contribute to the genetic diagnosis and counselling of families with CCD.