Search

The culprits of atherosclerosis are endothelial damage, local disorders of lipid metabolism, and progressive inflammation. Early atherosclerosis is typically difficult to diagnose in time due to the lack of obvious symptoms, thus missing the best period of treatment. In this work, a π-conjugated polymer (PMeTPP-MBT) based on 3,6-bis(4-methylthiophen-2-yl)-2,5-bis(2-octyldodecyl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione is designed as a novel photoacoustic contrast agent. On this basis, an intelligent responsive theranostic nanoplatform (PA/ASePSD) combining astaxanthin and SS-31 peptide and loading with PMeTPP-MBT is developed. The high affinity between the dextran shell with the broken endothelial surface VCAM-1 and CD44 confers active targeting of PA/ASePSD to atherosclerotic lesions. High levels of ROS in the acidic plaque microenvironment act as an intelligent cascade switch to achieve controlled release of astaxanthin, SS-31 peptide, and PMeTPP-MBT for non-invasive photoacoustic diagnosis, as well as plaque inhibition mediated by anti-inflammation and multichannel regulation (including ABCA1, ABCG1, CD36, and LOX-1) of lipid metabolism. Both in vitro and in vivo evaluations confirm the impressive anti-atherosclerotic capability and the accurate photoacoustic diagnosis of PA/ASePSD nanoparticles, thus promising a candidate for early-stage atherosclerosis theranostics., (© 2023 Wiley-VCH GmbH.)

Atherosclerosis, as a life-threatening cardiovascular disease with chronic inflammation and abnormal lipid enrichment, is often difficult to treat timely due to the lack of obvious symptoms. In this work, a theranostic nanoplatform is constructed for the noninvasive in vivo diagnosis, plaque-formation inhibition, and the lesion reversal of atherosclerosis. A three-in-one therapeutic complex is constructed and packaged along with a polymeric photoacoustic probe into nanoparticles named as PLCDP@PMH, which indicates an atherosclerosis-targeting accumulation and a reactive oxygen species (ROS)/matrix metalloproteinase (MMP) dual-responsive degradation. The photoacoustic probe suggests a lesion-specific imaging on atherosclerotic mice with an accurate and distinct recognition of plaques. At the same time, the three-in-one complex performs an integrated lipid management through the inhibition of macrophages M1-polarization, liver X receptor (LXR)-mediated up-regulation of ATP-binding cassette transporter A1/G1 (ABCA1/G1) and the cyclodextrin-assisted lipid dissolution, which lead to the reduced lipid uptake, enhanced lipid efflux, and actuated lipid removal. The in vivo evaluations reveal that PLCDP@PMH can suppress the lesion progression and further reverse the formed plaques under a diet without high fat. Hence, PLCDP@PMH provides a candidate for the theranostics of early-stage atherosclerosis and delivers an impressive potential on the reversal of formed atherosclerotic lesions., (© 2022 Wiley-VCH GmbH.)

Atherosclerosis, which is triggered by endothelial damage, progressive local inflammation and excessive lipid accumulation, is one of the most common cardiovascular diseases in recent years. Drug delivery systems have shown great potential for the accurate diagnosis and effective treatment of early atherosclerosis, but are accompanied by disadvantages such as poor stability, lack of active targeting and non-specific recognition capabilities, which still need to be further developed. In our work, a multifunctional nanoparticle (LFP/PCDPD) with reactive oxygen species (ROS) responsive drug release, lipid removal, and lipid-specific AIE fluorescence imaging was constructed. Cyclodextrin structure with lipid removal function and PMEMA blocks with ROS-response-mediated hydrophobic to hydrophilic conversion were simultaneously introduced into the structure of LFP/PCDPD to load the anti-inflammatory drug prednisolone (Pred) and lipid-specific AIEgen (LFP). The active targeting function of LFP/PCDPD was conferred by the high affinity of dextran to the vascular adhesion molecule-1 (VCAM-1) and CD44 receptor on the surface of broken endothelial cells. After intravenous injection into ApoE -/- mice, LFP/PCDPD actively enriched in the microenvironment of local ROS overexpression and rich lipids in atherosclerosis. Pred and LFP were released while lipids were removed, thus enabling proactive targeting of atherosclerosis and efficient "two-pronged" treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Atherosclerosis is one of the leading causes of cardiovascular diseases and is triggered by endothelial damage, local lipid cumulation, and inflammation. Despite the conventional medication treatment, nanosized drug carriers have become promising candidates for efficient drug delivery with lower side effects. However, the development of problems in nanocarriers such as drug leakage, accumulating efficiency, and accurate drug release, as well as the specific recognition of atherosclerotic plaques, still needs to be checked. In this study, a lipid-specific fluorophore (LFP) has been designed, which is further packaged with a reactive oxygen species (ROS)-responsive prednisolone (Pred) prodrug copolymer [PMPC-P(MEMA- co -PDMA)] to self-assemble into LFP@PMMP micelles. LFP@PMMP can be further coated with red blood cell (RBC) membrane to obtain surface-biomimetic nanoparticles (RBC/LFP@PMMP), demonstrating prolonged circulation, minimal drug leakage, and better accumulation at the plaques. With ROS responsiveness, RBC/LFP@PMMP can be interrupted at inflammatory atherosclerotic tissue with overexpressed ROS, followed by the dissociation of Pred from the polymer backbone and the release of LFP to combine with the rich lipid in the plaques. An accurate anti-inflammation and lipid-specific fluorescent imaging of atherosclerotic lesions was performed and further proven on ApoE -/- mice; this holds prospective potential for atherosclerosis theranostics.

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.

Atherosclerosis, characterized by endothelial injury, progressive inflammation, and lipid deposition, can cause cardiovascular diseases. Although conventional anti-inflammatory drugs reveal a certain amount of therapeutic effect, more reasonable design on plaque targeting, local anti-inflammation, and lipid removal are still required for comprehensive atherosclerosis therapy. In this work, a theranostic nanoplatform is developed for atherosclerosis recognition and inhibition. A two-photon aggregation-induced emission (AIE) active fluorophore (TP) developed is linked to β-cyclodextrin (CD) with a ROS responsive bond, which can carry prednisolone (Pred) in its entocoele via supramolecular interaction to build a diagnosis-therapy compound two-photon fluorophore-cyclodextrin/prednisolone complexes (TPCDP). With TPCDP packaged by nanosized micelles based on a ROS sensitive copolymer poly (2-methylthio ethanol methacrylate)-poly (2-methacryloyloxyethyl phosphorylcholine), the TPCDP@PMM can accumulate in atherosclerotic tissue through the damaged vascular endothelium. Activated by the local overexpressed ROS and rich lipid, the micelles are interrupted and TPCDP is further disintegrated with Pred release due to the relatively stronger interaction of lipid with CD, resulting in anti-inflammatory activity and lipid removal for atherosclerosis inhibition. Besides, labeled with the TP, TPCDP@PMM indicates a distinct two-photon AIE imaging on atherosclerosis recognition. The "two-pronged" therapeutic effect and plaque location ability has been confirmed in vivo on ApoE -/- mice, holding TPCDP@PMM a great promise for atherosclerosis theranostics., (© 2020 Wiley-VCH GmbH.)

Atherosclerosis can cause severe cardiovascular disease, which is usually diagnosed in late stages with life‐threatening complications. The lack of obvious symptoms limits its early diagnosis and timely treatment. In this work, a theranostic nanoplatform PGA@PMP is constructed for targeting photoacoustic diagnosis and a "hand‐in‐hand" immunoregulation of early‐stage atherosclerosis. Coated with biomimetic platelet membrane, PGA@PMP can actively target to the pathological endothelium and respond to the reactive oxygen species (ROS) in lesions for further disassembly and releasing photoacoustic probe along with immune‐regulate complex GWAS. The photoacoustic probe performs a noninvasive imaging with distinct recognition of plaques. In company, triggered by local cathepsin B, GWAS can be degraded for respective regulation on inducing M2 macrophages and stimulating regulatory T (Treg) cells. The transforming growth factor beta (TGF‐β) expressed by up‐regulated M2 macrophages also intensifies the Treg cell differentiation, which synergistically inhibits the foam cell formation and rebuilds a well‐balanced immune microenvironment. The in vivo evaluations suggest that the "hand‐in‐hand" strategy on regulating macrophages polarization and T cell differentiation indicates the restraint on atherosclerotic progression and the reversal of formed lesions even under high‐fat diet. Together, PGA@PMP provides an integrated solution for targeting theranostics of early‐stage atherosclerosis and delivers an exciting outcome of reversing the formed lesions. [ABSTRACT FROM AUTHOR]

• A lipid droplets (LDs) specific probe MeTTI was prepared. • The fluorescence emission of MeTTI was significantly enhanced in oleic acid. • MeTTI showed great LDs imaging performance in living cells. • MeTTI can be used to detect the LDs distribution in atherosclerosis plaques and human fibrocalcific bicuspid aortic valves. Lipid droplets (LDs) have been regarded as potential targets for the diagnosis of cardiovascular diseases. However, conventional LDs imaging strategies suffer from invasive sample collection and tedious histological preparations. Although fluorescence imaging has showed good performance in LDs imaging, ideal probes are still in urgent demand. In this work, fluorescent probe, namely, MeTTI was prepared for LDs visualization in cells and tissues. MeTTI exhibited low fluorescence quantum yield in dimethyl sulfoxide (Φ f = 0.2 %), while the value in the solid state was obvious increased (Φ f = 3.5 %), suggesting the aggregation-induced emission (AIE) property of MeTTI. Meanwhile, MeTTI would form excimers (emission ranged 750–850 nm) in water, and it showed good biocompatibility. Moreover, MeTTI exhibited impressive fluorescence emission enhancement in oleic acid (Φ f = 34.7 %) compared to that in water (Φ f = 1.11 %), which can specifically stain LDs in cells, atherosclerosis (AS) plaques and human fibrocalcific bicuspid aortic valves (FBAV) with high ratio of signal to noise. In addition, MeTTI could also monitor the dynamic changes of LDs in cells. These results were expected to provide a simple tool for studying the pathogenesis of cardiovascular diseases with lipid deposition and triggering enthusiasm to develop new imaging techniques for the diagnosis of these diseases. [ABSTRACT FROM AUTHOR]