Despite guideline-directed reperfusion and pharmacological therapies, myocardial infarction (MI) continues to pose substantial clinical challenges, with high incidence and mortality rates. Mesenchymal stromal cell (MSC) transplantation represents a promising therapeutic strategy, yet its efficacy remains limited by poor survival and unstable paracrine function of transplanted cells within the hostile infarct microenvironment. Here, we developed an integrated microcarrier system via digital light processing, which encapsulates MSCs within microgels functionalized with cardiac-derived decellularized extracellular matrix (dECM) particles (termed MSCs@dECMMG). By leveraging the native biochemical composition and structural cues of cardiac dECM, this bioinspired microcarrier was designed not only to enhance MSC viability but also to actively modulate their secretory activity. Conditioned medium from MSCs@dECMMG promoted angiogenic responses in human umbilical vein endothelial cells and attenuated oxidative stress‑induced apoptosis in H9c2 cells. In the rat MI model, local implantation of MSCs@dECMMG markedly improved the left ventricular ejection fraction from 32.03% to 60.77%, reduced the fibrotic area by 17.44%, and increased the left ventricular wall thickness by 2.6-fold. Collectively, this study demonstrates that a dECM‑integrated microgel can serve as a bioactive carrier that directs MSC secretory signaling, offering a novel strategy to advance cell‑based therapy for MI. STATEMENT OF SIGNIFICANCE: Low survival and unstable paracrine effects of transplanted MSCs in the hostile infarct microenvironment remain a major clinical challenge. Addressing how to specifically enhance MSC paracrine function is critical for effective cardiac repair. Here, we present a precision-engineered microcarrier system that integrates mechanically ground cardiac dECM particles into DLP-bioprinted microgels to deliver MSCs. Unlike prior studies focusing on proliferation or differentiation behaviors, we further uncovered and harnessed cardiac dECM to potentiate MSC paracrine signaling, markedly improving myocardial repair following MI. This introduces a new dimension to dECM application-from guiding differentiation to paracrine enhancement-while providing a translational-ready platform with scalability and controllability for future cell-based therapies.

Conductive hydrogels hold great promise for treating myocardial infarction (MI) by electrically coupling with the myocardium to improve the local microenvironment. However, their dense network often limits cellular infiltration and angiogenesis, while a mechanical mismatch with native heart tissues may provoke arrhythmia. Here, inspired by the biochemical and electrical microenvironment of the myocardium, we fabricated conductive hydrogel microspheres by first modifying a myocardial tissue-derived decellularized extracellular matrix (d-ECM) with methacryloyl groups to yield a photo-cross-linkable ECM hydrogel precursor. We generated uniformly sized ECM microspheres via a cross-shaped PDMS microfluidic chip, which were subsequently endowed with electrical conductivity via in situ oxidative polymerization of polypyrrole (PPY), resulting in ECM-PPY microspheres. In vitro studies demonstrated that ECM-PPY significantly upregulated the connexin 43 (Cx43) expression in cardiomyocytes. Moreover, the conductive microspheres promoted human umbilical vein endothelial cell migration and tube formation. In a rat MI model, treatment with ECM-PPY microspheres improved the cardiac function. Furthermore, the conductive microspheres reduced the fibrotic area, stimulated microvessel formation, increased the level of Cx43 expression, and suppressed cardiomyocyte apoptosis in the infarcted region. These findings demonstrate a conductive and bioactive microsphere-based strategy for myocardial repair after an MI.

Bioprosthetic heart valves (BHVs) crosslinked with glutaraldehyde (Glut-BP) have played an important role in replacement therapy for severe valvular heart disease. However, BHVs have a limited lifespan due to poor endothelialization, insufficient anticoagulation and anticalcification properties. In this work, we introduced exosomes rich in VEGF derived from human umbilical vein endothelial cells (HUVECs) into the surface of Glut-BP to increase its capacity for endothelialization. Compared with Glut-BP, the exosome-coated BHVs showed good biocompatibility, improved endothelialization and reduced thrombosis and calcification. Moreover, the exosome coating also reduced the adhesion of macrophages and improved the anti-inflammatory ability of Glut-BP. Overall, these findings suggest that coating BHVs with HUVECs exosomes might be a promising modification strategy for BHVs.

Glutaraldehyde (Glut) cross-linked bioprosthetic heart valves (BHVs) have shown great performance in the replacement treatment of severe valvular heart diseases in recent years due to the rapid development of transcatheter aortic valve replacement (TAVR) and the aging population. However, the durability of BHVs suffers from inflammation, limited endothelialization, thrombus formation and calcification during clinical application, which makes it urgently to prolong the service life of BHVs. To this end, we introduced exosomes derived from M2 macrophages to the surface of Glut cross-linked bovine pericardium (Glut-BP) to develop a novel kind of BHVs, namely M2-EXO-BP, to improve the durability of Glut-BP. Compared with Glut-BP, M2-EXO-BP presented significantly improved biocompatibility and endothelialization. Moreover, M2-EXO-BP also reduced the adhesion of platelets and the formation of thrombi during the ex-vivo arterial-venous blood circulation experiment. In addition, calcification of M2-EXO-BP after 60 days of subcutaneous implantation in SD rats was obvious reduced compared with Glut-BP. Importantly, in vitro and in vivo studies confirmed that M2-EXO-BP could efficiently reduce inflammation levels compared with Glut-BP. In summary, these results suggest that BHVs modified with exosomes from M2 macrophages might be an interesting strategy to improve the durability of BHVs.

Lipid deposition has been considered one of the key factors in the occurrence of valvular heart disease (VHD) and a great potential target for the diagnosis of VHD. However, the development of lipid imaging technologies and efficient lipid specific probes is in urgent demand. In this work, we have prepared a lipid droplets (LDs) targeted fluorescence probe CPTM based on a push-pull electronic structure for the imaging of diseased aortic valves. CPTM showed obvious twisted intramolecular charge transfer (TICT) effect and its emission changed from 600 nm in water to 508 nm in oil. CPTM not only exhibited good biocompatibility and high photostability, but also impressive LDs specific imaging performance in human primary valvular interstitial cells and human diseased aortic valves. Moreover, the dynamic changes of intracellular LDs could be monitor in real-time after staining with CPTM. These results were expected to offer new ideals for the designing of novel LDs specific probes for further bioimaging applications.

Fluorescent probes that specifically targeting Lipid droplets (LDs) have shown potential in biological imaging. Albeit, their in vivo applications are limited due to the hydrophobicity, low signal-to-noise ratio (SNR) and LDs-specificity. Thus, we designed a novel probe namely MeOND, and a reactive oxygen species (ROS)-responsive nano-platform to improve in vivo LDs-specific imaging. MeOND exhibits a remarkable twisted intramolecular charge transfer (TICT) effect with a strongly enhanced near-infrared emission in low-polarity lipid environment. Also, MeOND demonstrates satisfactory biocompatibility and superior intracellular LDs imaging capabilities. MeOND encapsulated nano-platform (MeOND@PMM) presented favorable water solubility and biocompatibility. MeOND@PMM remains stable in physiological conditions but quickly degrades in the environment of elevated ROS level. The released MeOND could then light up the intracellular LDs in atherosclerotic plaques. The design of the probe and nano-platform is expected to provide a better tool for the scientific research of LDs and LDs-related diseases.

Visualizing lipid droplets (LDs) using fluorescence imaging is highly desirable for the diagnosis and treatment of atherosclerotic heart diseases. However, the imaging performance of the current commercial lipid probes is unsatisfactory. In this study, we prepared two probes (TTM and MeO-TTM) with aggregation-induced emission (AIE) properties for LD imaging with efficiency. Interestingly, TTM and MeO-TTM showed low emissions in H2O but their emissions were significantly increased in oil. Moreover, TTM and MeO-TTM showed great biocompatibility and intracellular LDs would be specifically illuminated by these probes with good resistance to photobleaching. In addition, TTM and MeO-TTM also exhibited great imaging performance in studying the spatial distribution of LDs in mouse atherosclerotic plaques. This work not only provides a simple tool for studying atherosclerosis but also hopes to enhance the development of fluorescent probes for LDs-specific imaging applications.

Selective labelling of the plasma membrane (PM) by fluorescence imaging techniques enables an intuitive analysis of cell status together with dynamic changes, and therefore is of great value. We herein disclose a novel carbazole-based probe, CPPPy, that shows aggregation-induced emission (AIE) property and is observed to selectively accumulate at the PM of living cells. Benefiting from its good biocompatibility and PM-targeted specificity, CPPPy can light up the PM of cells by high-resolution imaging even at a low concentration of 200 nM. Simultaneously, CPPPy is capable of generating both singlet oxygen and free radical-dominated species upon visible light irradiation, which further induces irreversible growth inhibition and necrocytosis of tumor cells. This study thus provides new insight into the construction of multifunctional fluorescence probes with PM-specific bioimaging and photodynamic therapy.

Fluorescence imaging techniques have shown remarkable performance in studying the biological functions of lipid droplets (LDs). However, the biological applications of the commercially available LDs probes suffer from insufficient specificity and low signal/noise ratio (SNR). Herein, we presented a novel near-infrared (NIR) lipid activatable fluorescence probe, namely Me2NND, with extremely low emission in water but significantly enhanced emission in the lipid environment. Me2NND presented good biocompatibility and impressive LDs-specific imaging ability in cells and tissues. Moreover, Me2NND has also shown good photostability and it could efficiently locate the distribution of LDs in human pathological samples of aortic aneurysms and fibrocalcific stenotic aortic valves. This study provided a novel turn-on probe Me2NND and would improve the bio-applications of LDs-specific probes.

ErbB2 is overexpressed in 15-20% of breast cancer, which is associated with malignancy and poor prognosis. We previously reported that ErbB2 supports malignant progression of breast cancer by upregulating lactate dehydrogenase A (LDHA), an important enzyme in glycolysis. However, whether ErbB2 promotes breast cancer progression through other glycolytic enzymes remains unclear. Hexokinase 1 (HK1) and hexokinase 2 (HK2) are the first rate-limiting enzymes of glycolysis and both of them are increased in breast cancer. Here, we aim to investigate whether ErbB2 upregulates HK1 and HK2 and the role of HK1 and HK2 in the malignant progression of ErbB2-overexpressing breast cancer. In current study, we found that the mRNA level of ErbB2 was positively correlated with that of HK1 and HK2, respectively. Moreover, ErbB2 upregulated the protein levels of HK1 and HK2 in breast cancer cells. We also found that both siHK1 and siHK2 significantly inhibited the proliferation, migration and invasion of ErbB2-overexpressing breast cancer cells. Taken together, our findings suggested that ErbB2 promoted the malignant progression of breast cancer cells by upregulating HK1 and HK2, and HK1 and HK2 might serve as promising therapeutic targets for ErbB2-overexpressing breast cancer.

Hydrophobic lipid droplets (LDs)-specific fluorescent probes have shown great potential in bioimaging. However, their in vivo bioapplications are also limited by their strong hydrophobic nature. To address this issue, we pre -pared a novel tetraphenylethylene (TPE)-based fluorescent probe, namely, MeOTTI, and a pH-responsive polymeric micelle to establish a nanodiagnostic system for the imaging of LDs in atherosclerosis. MeOTTI demonstrated good LDs-specific imaging capability with good anti-photobleaching ability but poor water solu-bility. MeOTTI-encapsulated nanoparticles (MeOTTI-PMEA NPs) have shown improved water solubility and biocompatibility of MeOTTI. MeOTTI-PMEA NPs exhibited great stability at pH 7.4, while they showed good acid-responsive ability with accelerated MeOTTI release. Importantly, MeOTTI-PMEA NPs could efficiently light up the LDs in cells and in mice atherosclerosis plaques. The construction of LDs-specific probe-loaded nano-diagnostic system is expected to create enthusiasm for the development of new tools for bioimaging.

Cerulenin is a fungal metabolite and a specific inhibitor of fatty acid synthase (FASN), which has shown a potential anticancer activity. 20-25% of breast cancer patients with ErbB2-overexpressing develop resistance to treatment. Therefore, it is urgent to find an effective new target for the treatment of ErbB2-overexpressing breast cancer. Our previous study found that cerulenin inhibits the glycolysis and migration of SK-BR-3 cells, but the effect of cerulenin on other malignant phenotypes of breast cancer is still unknown. Furthermore, the mechanism by which cerulenin displays its inhibitory effects is not fully understood. In this study, we systematically investigate the inhibitory effects of cerulenin on proliferation, migration, invasion and glycolysis of ErbB2-overexpressing breast cancer cells and its molecular mechanism. We found that cerulenin obviously suppresses the proliferation, migration, invasion as well as glycolysis. Through bioinformatic analyses, we found that PKM2 might be a target of cerulenin. In addition, ErbB2 and its signaling pathway upregulated PKM2 protein levels. Furthermore, we demonstrated that cerulenin downregulated the protein levels of ErbB2, PKM2 and EMT markers (MMP9, MMP2 and Snail2) in a dose- and time-dependent manner. Finally, the inhibitory of cerulenin on colony formation, migration, invasion and glycolysis, as well as protein levels of EMT markers were rescued by replenishing with PKM2. These findings illustrated that cerulenin inhibits proliferation, migration, invasion and glycolysis by targeting ErbB2/PKM2 pathway in ErbB2-overexpressing breast cancer cells.

The dysregulation of lipid droplets (LDs) is closely related to certain metabolic diseases, while the role of LDs during pathological processes remains mysterious. It would be of great value to monitor the dynamic changes of LDs in a visible way so as to study their biological functions. In this study, we report a LD-specific fluorescence probe TBI for precise LD-targeting imaging in cells and atherosclerotic tissues. TBI exhibited great biocompatibility, remarkable oil-enhanced fluorescence emission, good photostability and impressive intracellular and tissular LD-specific imaging performance. Importantly, TBI could efficiently stain the LDs at a low concentration of 50 nM, and the motion tracking of LDs could be observed via fluorescence imaging. Moreover, TBI could efficiently light up the LD distribution in mouse atherosclerotic plaques with high resolution, which revealed the ultra-structure of atherosclerotic plaques. In conclusion, these results imply that TBI could be a potential tool for investigating the physiological and pathological role of LDs.

Fluorescence probes have shown great potential in lipid droplets (LDs) imaging, whereas the imaging perfor-mance of the present commercial dyes is far from ideal. In addition, there still is lack of an effective strategy for designing LDs specific probes with satisfactory imaging performance. In this work, we have provided a novel method and probes based on donor (D)-acceptor (A) structure with nitrobenzoxadiazole (NBD) as the A unit and benzene derivatives as the D units, which are expected to show strong emission in lipid environment. Four probes (N-B, N-MeB, N-MeOB and N-Me2NB) with increasing electron-donating ability were prepared, whose fluorescence-emission changed from aggregation-induced emission (AIE) (N-B and N-MeB) to aggregation -caused quenching (ACQ) (N-MeOB and N-Me2NB). Intriguingly, the emission of these probes in oil changed from blue region to red (652 nm) with the increase of electron-donating ability from N-B to N-Me2NB, indi-cating the great emission regulable ability of this strategy. Moreover, these probes could specifically stain the intracellular and tissular LDs, which had shown considerable performance in the studying of LDs spatial dis-tributions in mice and human atherosclerosis plaques. Impressively, N-Me2NB with the strongest electron -donating group of N-dimethylaniline showed negligible emission in aqueous solution but remarkable enhanced emission in oil, which could still efficiently stain the intracellular LDs at 200 nM. This novel con-struction strategy would provide new ideas for preparation of LDs specific probes.

Lipid droplets (LDs) have been regarded as potential marker for study the pathologic processes and diagnosis of valvular heart disease. While conventional imaging strategy fail to precisely locate LDs in pathological tissues. Herein, a LDs specific probe ECPID with special feature of single-excitation but dual-emission in oil (520 nm) and water (628 nm) was prepared for LDs imaging. ECPID exhibited good biocompatibility, great performance in intracellular and tissular LDs imaging, which would help to reveal the pathologic process of human fibrocalcific aortic valvular leaflet. Our work offers a novel approach for accurate imaging LDs in situ and paves a way to study the pathologic processes of valvular disease.

Glutaraldehyde (Glut)-crosslinked porcine pericardium and bovine pericardium are mainly consisted of collagen and widely used for the preparation of heterogenous bioprosthetic heart valves (BHV), which play an important role in the replacement therapy of severe valvular heart disease, while their durability is limited by degeneration due to calcification, thrombus, endothelialization difficulty and prosthetic valve endocarditis. Herein, we develop a novel BHV, namely, TPly-BP, based on natural tannic acid and polylysine to improve the durability of Glut crosslinked bovine pericardium (Glut-BP). Impressively, tannic acid and polylysine could form nanoaggregates via multiple hydrogen bonds and covalent bonds, and the introduction of nanoaggregates not only improved the mechanical properties and collagen stability but also endowed TPly-BP with good biocompatibility and hemocompatibility. Compared to Glut-BP, TPly-BP showed significantly reduced cytotoxicity, improved endothelial cell adhesion, a low hemolysis ratio and obviously reduced platelet adhesion. Importantly, TPly-BP exhibited great antibacterial and in vivo anti-calcification ability, which was expected to improve the in vivo durability of BHVs. These results suggested that TPly-BP would be a potential candidate for BHV. Graphical abstract

The incidence of breast cancer ranks at the top of female malignant tumors in China. Metastasis remains the main cause of death among breast cancer patients. The overexpression of ErbB2 is closely related to the metastasis and poor prognosis of breast cancer patients. Therefore, ErbB2 is an important clinical therapeutic target of breast cancer. However, the molecular mechanism of ErbB2 promoting breast cancer metastasis has not been studied clearly. Stearoyl-CoA desaturase 1 (SCD1) is a key enzyme in catalyzing the conversion of saturated fatty acids (SFAs) into monounsaturated fatty acids (MUFAs). SCD1 is overexpressed in breast cancer, and its overexpression is an indicator of poor prognosis in breast cancer patients. However, the role of SCD1 in ErbB2-overexpressing breast cancer metastasis has not been reported. In this study, we investigated the role of SCD1 in the migration and invasion of ErbB2-overexpressing breast cancer cells and its molecular mechanism. First, we demonstrated that ErbB2 upregulates the expression of SCD1. Second, we found that SCD1 and its catalytic product oleic acid played crucial roles in migration and invasion of ErbB2-overexpressing breast cancer cells. Finally, we found that in breast cancer cells, ErbB2 upregulated SCD1 through lactate dehydrogenase A (LDHA). To sum up, upregulation of SCD1 by ErbB2 via LDHA promotes the migration and invasion of breast cancer cells.

Selective labelling and high-fidelity tracking of intracellular lipid droplets (LDs) can provide direct insight into pathological processes associated with abnormal lipid metabolism and therefore are of great value. We herein present a novel imidazole-based probe, TITM, which shows the aggregation-induced emission property and a remarkable fluorescence increase in sunflower oil than in water. With the advantages of good lipophilicity, biocompatibility, and LDs-targeted specificity, TITM allows the real-time and long-term tracking of dynamic LDs in living cells with high-resolution imaging performance. By establishment of LDs-related atherosclerosis (AS) and fatty liver mouse model, the imaging performance of TITM at pathological tissue level is well studied to show impressive selectivity and resolution.

Fluorescence imaging plays an important role in researching the biological function of lipid droplets (LDs). However, the short-wave emission, tedious synthesis process and insufficient specificity have significantly limited the applications of commercially available probes. Herein, we have prepared a novel one-step synthesized near-infrared (NIR) fluorescent probe, TNBD, with a very low emission in aqueous solution and the solid state, but a significantly enhanced fluorescence emission is exhibited in oleic acid. Moreover, TNBD exhibited an impressive lipid droplet (LD) specific fluorescence turn-on ability in cells, fatty liver and atherosclerosis (AS) samples with a good biocompatibility and high signal-to-noise ratio. Our study not only establishes a novel LD turn-on fluorescence probe, but also provides a novel way to prepare a NIR LD targeted fluorescence probe.

目的 在体外研究小干扰RNA(siRNA)沉默己糖激酶2(HK2)对人乳腺癌SK-BR-3细胞增殖、迁移和侵袭的影响及其分子机制.方法 在SK-BR-3细胞中分别转染siRNA阴性、siHK2-A和siHK2-B,分别采用荧光定量PCR和Western Blot法检测HK2 mRNA和蛋白的表达水平;MTT法检测细胞的增殖;Transwell小室检测细胞的迁移和侵袭;葡萄糖检测试剂盒检测细胞对葡萄糖的摄取.结果 与阴性对照组比较,siHK2能显著降低SK-BR-3细胞的HK2 mRNA及蛋白水平,抑制细胞增殖、迁移和侵袭能力,减少细胞对葡萄糖的摄取.结论 siHK2可能通过降低葡萄糖摄取来抑制SK-BR-3细胞的增殖、迁移和侵袭.