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Background Psoriasis is an immune-mediated inflammatory skin disease, in which an interplay between infiltrating immune cells and keratinocytes sustains chronic skin inflammation. Interleukin (IL)-17A is a key inflammatory cytokine in psoriasis and its main cellular targets are keratinocytes. Objectives To explore the role of miR-378a in psoriasis. Methods Keratinocytes obtained from psoriatic skin and healthy epidermis were separated by magnetic sorting, and the expression of miR-378a was analysed by quantitative polymerase chain reaction. The regulation and function of miR-378a was studied using primary human keratinocytes. The expression of miR-378a was modulated by synthetic mimics, and nuclear factor kappa B (NF-κB) activity and transcriptomic changes were studied. Synthetic miR-378a was delivered to mouse skin in conjunction with induction of psoriasiform skin inflammation by imiquimod. Results We show that miR-378a is induced by IL-17A in keratinocytes through NF-κB, C/EBP-β and IκBζ and that it is overexpressed in psoriatic epidermis. In cultured keratinocytes, ectopic expression of miR-378a resulted in the nuclear translocation of p65 and enhanced NF-κB-driven promoter activity even in the absence of inflammatory stimuli. Moreover, miR-378a potentiated the effect of IL-17A on NF-κB nuclear translocation and downstream activation of the NF-κB pathway. Finally, injection of miR-378a into mouse skin augmented psoriasis-like skin inflammation with increased epidermal proliferation and induction of inflammatory mediators. Mechanistically, miR-378a acts as a suppressor of NFKBIA/IκBζ, an important negative regulator of the NF-κB pathway in keratinocytes. Conclusions Collectively, our findings identify miR-378a as an amplifier of IL-17A-induced NF-κB signalling in keratinocytes and suggest that increased miR-378a levels contribute to the amplification of IL-17A-driven skin inflammation in psoriasis.

FMS-like receptor tyrosine kinase 3 (Flt3) expression was reported to increase in the heart in response to pathological stress, but the role of Flt3 activation and its underlying mechanisms remain poorly elucidated. This study was designed to investigate the role of Flt3 activation in sympathetic hyperactivity-induced cardiac hypertrophy and its mechanisms through autophagy and mitochondrial dynamics. In vivo, cardiac hypertrophy was established by subcutaneous injection of isoprenaline (6 mg/kg·day) in C57BL/6 mice for 7 consecutive days. The Flt3-ligand intervention was launched 2 h prior to isoprenaline each day. In vitro, experiments of cardiomyocyte hypertrophy, autophagy, and mitochondrial dynamics were performed in neonatal rat cardiomyocytes (NRCMs). Our results revealed that the expression level of Flt3 protein was significantly increased in the hypertrophic myocardium provoked by isoprenaline administration. Flt3-ligand intervention alleviated isoprenaline-induced cardiac oxidative stress, hypertrophy, fibrosis, and contractile dysfunction. Isoprenaline stimulation impaired autophagic flux in hypertrophic mouse hearts, supported by the accumulation of LC3II and P62 proteins, while Flt3-ligand restored the impairment of autophagic flux. Flt3 activation normalized the imbalance of mitochondrial fission and fusion in the hearts of mice evoked by isoprenaline as evidenced by the neutralization of elevated mitochondrial fission markers and reduced mitochondrial fusion markers. In NRCMs, Flt3-ligand treatment attenuated isoprenaline-stimulated hypertrophy, which was abolished by a Flt3-specific blocker AC220. Activating Flt3 reversed isoprenaline-induced autophagosome accumulation and impairment of autophagic flux probably by enhancing SIRT1 expression and consequently TFEB nuclear translocation. Flt3 activation improved the imbalance of mitochondrial dynamics induced by isoprenaline in NRCMs through the SIRT1/P53 pathway. Activation of Flt3 mitigated ISO-stimulated hypertrophy probably involves the restoration of autophagic flux and balance of mitochondrial dynamics. Therefore, activation of Flt3 attenuates isoprenaline-induced cardiac hypertrophy in vivo and in vitro, the potential mechanism probably attributes to SIRT1/TFEB-mediated autophagy promotion and SIRT1/P53-mediated mitochondrial dynamics balance. These findings suggest that activation of Flt3 may be a novel target for protection against cardiac remodeling and heart failure during sympathetic hyperactivity.

The soft nature has endowed conjugated polymers with promising applications in a wide range of field‐effect transistor (FET) based flexible electronics. With unremitting efforts on revealing the molecular structure–property relationships, numerous novel conjugated polymers with high mobility and excellent mechanical property have been developed in the past decades. Incorporating hydrogen‐bonding (H‐bonding) units into semiconducting polymers is one of the most successful strategies for designing high‐performance semiconducting materials. In this review, we aim to highlight the roles of H‐bonding units in the performances of polymeric FETs from three aspects. These include (i) charge mobility enhancement for semiconducting polymers after incorporation of H‐bonding units into the side chains, (ii) the effects of H‐bonding units on the stretchability of conjugated polymers, and (iii) the improvement of self‐healing properties of conjugated polymers containing dynamic hydrogen bonds due to the H‐bonding units in the side chains or conjugated backbones.

A diazirine-based four-armed cross-linker (4CNN) with a tetrahedron geometry is presented for efficient patterning of polymeric semiconductors by photo-induced carbene insertion. After blending of 4CNN with no more than 3 % (w/w), photo-patterning of p-, n-, and ambipolar semiconducting polymers with side alkyl chains was achieved; regular patterns with size as small as 5 μm were prepared with appropriate photomasks after 365 nm irradiation for just 40 s. The interchain packing order and the thin film morphology were nearly unaltered after the cross-linking and the semiconducting properties of the patterned thin films were mostly retained. A complementary-like inverter with a gain value of 112 was constructed easily by two steps of photo-patterning of the p-type and n-type semiconducting polymers. The results show that 4CNN is a new generation of cross-linker for the photo-patterning of polymeric semiconductors for all-solution-processible flexible electronic devices.

Neointimal hyperplasia is the major cause of carotid stenosis after vascular injury, which restricts the long-term efficacy of endovascular treatment and endarterectomy in preventing stenosis. Ginsenoside Re (Re) is a major active ingredient of ginseng having multifaceted pharmacological effects on the cardiovascular system, and is a potential treatment for restenosis. In this study, we demonstrated that Re treatment significantly inhibited vascular injury-induced neointimal thickening, reduced the intimal area and intima/media (I/M) ratio, increased the lumen area, and inhibited pro-inflammatory cytokines. In cultured A7R5 cells, Re inhibited LPS-induced proliferation and migration as evidenced by suppressed colony formation and shortened migration distance, accompanied by the downregulated expression of pro-inflammatory cytokines. Re promoted VSMC apoptosis induced by balloon injury in vivo and LPS challenge in vitro. Moreover, Re inhibited autophagy in VSMCs evoked by balloon injury and LPS as supported by reduced LC3II and increased p62 expressions. Suppression of autophagy with the specific autophagy inhibitor spautin-1 efficiently inhibited LPS-induced cell proliferation and inflammation and promoted caspase-3/7 activities. Mechanistically, we found that Re attenuated Ras/ERK1/2 expression in VSMCs in vivo and in vitro. The MEK1/2 inhibitor PD98059 showed similar effects to Re on cell proliferation, migration, apoptosis, and the levels of autophagy and cytokines. In conclusion, we provided significant evidence that Re inhibited vascular injury-induced neointimal thickening probably by promoting VSMC apoptosis and inhibiting autophagy via suppression of the Ras/MEK/ERK1/2 signaling pathway.

Sorafenib, a multi-kinase inhibitor, is recommended as a new standard therapy for advanced hepatocellular carcinoma (HCC); however, it also exhibits severe cardiotoxicity and the toxicity mechanisms are not completely elucidated. Recent studies suggested that sorafenib-enhanced ROS may partially contribute to its anti-HCC effect, which implies that redox mechanism might also be involved in sorafenib's cardiotoxicity. In this study, we aimed to investigate if sorafenib is able to induce oxidative stress and how this may impair cellular functions in cardiomyocyte, ultimately accounting for its cardiotoxicity. Our results showed that in isolated rat hearts, sorafenib caused ventricular arrhythmias and left ventricular dysfunction, which were alleviated by the antioxidant N-(2-mercaptopropionyl)-glycine (MPG). In isolated ventricular myocytes, sorafenib increased diastolic intracellular Ca2+ levels, decreased Ca transients and the occurrence of Ca2+ waves. These changes were eliminated by MPG, CaMKII inhibitor KN-93 and the mitochondrial permeability transition pore (mPTP)inhibitor cyclosporin A (CsA). Moreover, the levels of oxidized and phosphorylated CaMKII were significantly increased. Sorafenib elevated ROS levels, which was reversed by CsA and MPG; additionally, sorafenib reduced the activity of mitochondrial complex III and augmented mitochondrial ROS production. In vivo rats treated with sorafenib exhibited a reduction of antioxidant defence and abnormal histological alterations including hypertrophy, increased fibrosis, disordered myofibrils and damaged mitochondria, which were protected by MPG. We conclude that sorafenib induces the disruption of Ca2+ homoeostasis and cardiac injury via enhanced ROS potentially through inhibiting mitochondrial complex III, the opening of mPTP and overactivating CaMKII. These results provide a potential strategy for preventing or reducing cardiotoxicity of sorafenib.

Ortho direct arylation of O-phenylcarbamates using aryl boronates as coupling partners has been realized for the first time in the literature. A mechanistic investigation showed that the Wheland intermediate with ortho C–H remaining after carbopalladation was the key intermediate for further transformation. Isotope competition experiments indicated that C–H cleavage was not involved in the rate-determining step.

AIM FMS-like receptor tyrosine kinase 3 (Flt3) has been reported to be increased in cardiomyocytes responding to ischaemic stress. This study was to determine whether Flt3 activation could ameliorate pressure overload-induced heart hypertrophy and fibrosis, and to elucidate the mechanisms of action. METHODS In vivo cardiac hypertrophy and remodelling experiments were conducted by infusing angiotensin II (Ang II) chronically in male C57BL/6 mice. Flt3-specific ligand (FL) was administered intraperitoneally every two days (5 µg/mouse). In vitro experiments on hypertrophy, apoptosis and autophagy mechanism were performed in neonatal rat cardiomyocytes (NRCMs) and H9c2 cells with adenovirus vector-mediated overexpression of Flt3. RESULTS Our results demonstrated that following chronic Ang II infusion for 4 weeks, the mice exhibited heart hypertrophy, fibrosis, apoptosis and contractile dysfunction. Meanwhile, Ang II induced autophagic responses in mouse hearts, as evidenced by increased LC3 II and decreased P62 expression. These pathological alterations in Ang II-treated mice were significantly ameliorated by Flt3 activation with FL administration. In NRCMs and Flt3-overexpressed H9c2 cells, FL attenuated Ang II-induced pathological autophagy and inactivated AMPK/mTORC1/FoxO3a signalling, thereby efficiently mitigating cell hypertrophy and apoptosis. Conversely, the AMPK activator metformin or the mTORC1 inhibitor rapamycin reversed the effects of FL on the alterations of autophagy, hypertrophy and apoptosis in cardiomyocytes induced by Ang II. CONCLUSION Flt3 activation ameliorates cardiac hypertrophy, fibrosis and contractile dysfunction in the mouse model of chronic pressure overload, most likely via suppressing AMPK/mTORC1/FoxO3a-mediated autophagy. These results provide new evidence supporting Flt3 as a novel therapeutic target in maladaptive cardiac remodelling.

Aim: FMS-like tyrosine kinase 3 (Flt3) is a receptor tyrosine kinase. This study was to determine whether activation Flt3 could regulate autophagy ameliorate AngII-induced heart cardiac remodeling and to elucidate the mechanisms of action. Methods: In vivo cardiac remodeling was induced in male C57BL/6 mice by implanting subcutaneously osmotic minipumps releasing Angiotensin II (Ang II) for 28 days (1100ng/kg/min). Flt3 ligand (FL) was administered intraperitoneally (5μg/mouse/2days). Heart hypertrophy, fibrosis and function were evaluated based on echocardiography, histological and biochemical measurements. In vitro, hypertrophy was induced by Ang II on adenovirus vector-mediated overexpression Flt3 receptor in H9c2 cells, and NRCMs. Crystal violet staining, flow cytometry and TUNEL were used for in vitro experiments. The levels of signaling proteins were measured using western blotting, while the expression of the relevant genes was analyzed using real-time qRT-PCR. Results: Echocardiography demonstrated that Ang II induced marked damaged heart function, while cardiac Flt3 receptor activation significantly decrease left ventricular internal dimension at end-diastole (LVIDd), left ventricular posterior wall thickness at end-diastole (LVPWd), and increase ejection fraction (EF%) and fractional shortening (FS%). FL-treated mice showed a significant attenuation of cardiac hypertrophy, ratios of heart weight/body weight (HW/BW) and heart weight/tibia length (HW/TL), as well as cardiac fibrosis and apoptosis. Additionally, the autophagic levels in cardiomyocytes of FL-treated mice were distinctly decreased as evidenced by expression of LC3 in immunohistochemical staining and western blotting. In H9c2 cells with adenovirus vector-mediated overexpression of Flt3 and neonatal rat cardiomyocytes, FL treatment significantly decrease the cell size, apoptosis and autophagy induced by Ang II. Additionally, using rapamycin or metformin, respectively canceled FL protective effects. Conclusion: Flt3 activation suppresses Ang II-induced cardiac hypertrophy and apoptosis via AMPK /mTOR/ FOXO3a autophagy signaling pathway. These results provide evidence supporting Flt3 as a novel therapeutic target in cardiac remodeling.