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1.
Sci Adv ; 10(16): eadj0268, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38640247

ABSTRACT

Continuous monitoring of biomarkers at locations adjacent to targeted internal organs can provide actionable information about postoperative status beyond conventional diagnostic methods. As an example, changes in pH in the intra-abdominal space after gastric surgeries can serve as direct indicators of potentially life-threatening leakage events, in contrast to symptomatic reactions that may delay treatment. Here, we report a bioresorbable, wireless, passive sensor that addresses this clinical need, designed to locally monitor pH for early detection of gastric leakage. A pH-responsive hydrogel serves as a transducer that couples to a mechanically optimized inductor-capacitor circuit for wireless readout. This platform enables real-time monitoring of pH with fast response time (within 1 hour) over a clinically relevant period (up to 7 days) and timely detection of simulated gastric leaks in animal models. These concepts have broad potential applications for temporary sensing of relevant biomarkers during critical risk periods following diverse types of surgeries.


Subject(s)
Absorbable Implants , Transducers , Animals , Wireless Technology , Hydrogen-Ion Concentration , Biomarkers
2.
J Vis Exp ; (204)2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38372398

ABSTRACT

Cell patterning, allowing precise control of cell positioning, presents a unique advantage in the study of cell behavior. In this protocol, a cell patterning strategy based on the Magnetic-Archimedes (Mag-Arch) effect is introduced. This approach enables precise control of cell distribution without the use of ink materials or labeling particles. By introducing a paramagnetic reagent to enhance the magnetic susceptibility of the cell culture medium, cells are repelled by magnets and arrange themselves into a pattern complementary to the magnet sets positioned beneath the microfluidic substrate. In this article, detailed procedures for cell patterning using the Mag-Arch-based strategy are provided. Methods for patterning single-cell types as well as multiple cell types for co-culture experiments are offered. Additionally, comprehensive instructions for fabricating microfluidic devices containing channels for cell patterning are provided. Achieving this feature using parallel methods is challenging but can be done in a simplified and cost-effective manner. Employing Mag-Arch-based cell patterning equips researchers with a powerful tool for in vitro research.


Subject(s)
Magnetics , Microfluidics , Coculture Techniques , Indicators and Reagents , Magnetic Phenomena
3.
Nat Commun ; 15(1): 557, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38228638

ABSTRACT

Calcific aortic valve disease is a prevalent cardiovascular disease with no available drugs capable of effectively preventing its progression. Hence, an efficient drug delivery system could serve as a valuable tool in drug screening and potentially enhance therapeutic efficacy. However, due to the rapid blood flow rate associated with aortic valve stenosis and the lack of specific markers, achieving targeted drug delivery for calcific aortic valve disease has proved to be challenging. Here we find that protease-activated-receptor 2 (PAR2) expression is up-regulated on the plasma membrane of osteogenically differentiated valvular interstitial cells. Accordingly, we develop a magnetic nanocarrier functionalized with PAR2-targeting hexapeptide for dual-active targeting drug delivery. We show that the nanocarriers effectively deliver XCT790-an anti-calcification drug-to the calcified aortic valve under extra magnetic field navigation. We demonstrate that the nano-cargoes consequently inhibit the osteogenic differentiation of valvular interstitial cells, and alleviate aortic valve calcification and stenosis in a high-fat diet-fed low-density lipoprotein receptor-deficient (Ldlr-/-) mouse model. This work combining PAR2- and magnetic-targeting presents an effective targeted drug delivery system for treating calcific aortic valve disease in a murine model, promising future clinical translation.


Subject(s)
Aortic Valve Stenosis , Calcinosis , Mice , Animals , Aortic Valve/metabolism , Aortic Valve Stenosis/drug therapy , Osteogenesis , Calcinosis/drug therapy , Calcinosis/metabolism , Cells, Cultured , Magnetic Phenomena
4.
Lab Chip ; 23(22): 4901-4908, 2023 11 07.
Article in English | MEDLINE | ID: mdl-37874569

ABSTRACT

Single-nanoparticle detection has received tremendous interest due to its significance in fundamental physics and biological applications. Here, we demonstrate an optical nanofibre-enabled microfluidic sensor for the detection and sizing of nanoparticles. Benefitting from the strong evanescent field outside the nanofibre, a nanoparticle close to the nanofibre can scatter a portion of the field energy to the environment, resulting in a decrease in the transmitted intensity of the nanofibre. On the other hand, the narrow and shallow microfluidic channel provides a femtoliter-scale detection region, making nanoparticles flow through the detection region one by one. By real-time monitoring of the transmitted intensity of the nanofibre, the detection of a single polystyrene (PS) nanoparticle as small as 100 nm in diameter and exosomes in solution is realised. Based on a statistical analysis, the mean scattering signal is related to the size of the nanoparticle. Experimentally, a mixture of nanoparticles of different diameters (200, 500, and 1000 nm) in solution is identified. To demonstrate its potential in biological applications, high-throughput counting of yeasts using a pair of microchannels and dual-wavelength detection of fluorescently labelled nanoparticles are realised. We believe that the developed nanoparticle sensor holds great potential for the multiplexed and rapid sensing of diverse viruses.


Subject(s)
Nanofibers , Nanoparticles , Microfluidics , Polystyrenes
5.
J Am Chem Soc ; 145(24): 13195-13203, 2023 Jun 21.
Article in English | MEDLINE | ID: mdl-37305923

ABSTRACT

Polymer/metal-organic framework (MOF) composites have been widely studied for their favorable combination of polymer flexibility and MOF crystallinity. While traditional polymer-coated MOFs maximize the polymer properties at the surface, the dramatic loss of MOF porosity due to blockage by the nonporous polymeric coating remains a problem. Herein, we introduce intrinsically microporous synthetic allomelanin (AM) as a porous coating on the zirconium-based MOF (Zr-MOF) UiO-66 via an in situ surface-constrained oxidative polymerization of the AM precursor, 1,8-dihydroxynaphthalene (1,8-DHN). Transmission electron microscopy images verify the formation of well-defined nanoparticles with a core-shell morphology (AM@UiO-66), and nitrogen sorption isotherms indicate the porosity of the UiO-66 core remains constant and is not disturbed by the AM coating. Notably, such a strategy could be adapted to MOFs with larger pores, such as MOF-808 by generating porous AM polymer coatings from bulkier DHN oligomers, highlighting the versatility of this method. Finally, we showed that by tuning the AM coating thickness on UiO-66, the hierarchically porous structures of these AM@UiO-66 composites engender excellent hexane isomer separation selectivity and storage capacity.

6.
ACS Nano ; 17(13): 12072-12086, 2023 07 11.
Article in English | MEDLINE | ID: mdl-37363813

ABSTRACT

Tissue engineering raised a high requirement to control cell distribution in defined materials and structures. In "ink"-based bioprintings, such as 3D printing and photolithography, cells were associated with inks for spatial orientation; the conditions suitable for one ink are hard to apply on other inks, which increases the obstacle in their universalization. The Magneto-Archimedes effect based (Mag-Arch) strategy can modulate cell locomotion directly without impelling inks. In a paramagnetic medium, cells were repelled from high magnetic strength zones due to their innate diamagnetism, which is independent of substrate properties. However, Mag-Arch has not been developed into a powerful bioprinting strategy as its precision, complexity, and throughput are limited by magnetic field distribution. By controlling the paramagnetic reagent concentration in the medium and the gaps between magnets, which decide the cell repelling scope of magnets, we created simultaneously more than a hundred micrometer scale identical assemblies into designed patterns (such as alphabets) with single/multiple cell types. Cell patterning models for cell migration and immune cell adhesion studies were conveniently created by Mag-Arch. As a proof of concept, we patterned a tumor/endothelial coculture model within a covered microfluidic channel to mimic epithelial-mesenchymal transition (EMT) under shear stress in a cancer pathological environment, which gave a potential solution to pattern multiple cell types in a confined space without any premodification. Overall, our Mag-Arch patterning presents an alternative strategy for the biofabrication and biohybrid assembly of cells with biomaterials featured in controlled distribution and organization, which can be broadly employed in tissue engineering, regenerative medicine, and cell biology research.


Subject(s)
Cell Culture Techniques , Ink , Tissue Engineering/methods , Cell Communication , Microfluidic Analytical Techniques , Coculture Techniques , Cell Movement , Magnetics , Humans , Cell Culture Techniques/methods
7.
Chem Sci ; 14(15): 4183-4192, 2023 Apr 12.
Article in English | MEDLINE | ID: mdl-37063797

ABSTRACT

Herein, we investigate synthetic routes to a close mimic of natural pheomelanin. Three different oxidative polymerization routes were attempted to generate synthetic pheomelanin, each giving rise to structurally dissimilar materials. Among them, the route employing 5-cysteinyl-dihydroxyphenylalanine (5-CD) as a monomer was verified as a close analogue of extracted pheomelanin from humans and birds. The resulting biomimetic and natural pheomelanins were compared via various techniques, including solid-state Nuclear Magnetic Resonance (ssNMR) and Electron Paramagnetic Resonance (EPR). This synthetic pheomelanin closely mimics the structure of natural pheomelanin as determined by parallel characterization of pheomelanin extracted from multiple biological sources. With a good synthetic biomimetic material in hand, we describe cation-π interactions as an important driving force for pheomelanogenesis, further advancing our fundamental understanding of this important biological pigment.

8.
Cell Mol Life Sci ; 80(5): 118, 2023 Apr 06.
Article in English | MEDLINE | ID: mdl-37022488

ABSTRACT

Regeneration of smooth muscle cells (SMCs) is vital in vascular remodeling. Sca1+ stem/progenitor cells (SPCs) can generate de novo smooth muscle cells after severe vascular injury during vessel repair and regeneration. However, the underlying mechanisms have not been conclusively determined. Here, we reported that lncRNA Metastasis-associated lung adenocarcinoma transcript 1 (Malat1) was down-regulated in various vascular diseases including arteriovenous fistula, artery injury and atherosclerosis. Using genetic lineage tracing mice and veingraft mice surgery model, we found that suppression of lncRNA Malat1 promoted Sca1+ cells to differentiate into SMCs in vivo, resulting in excess SMC accumulation in neointima and vessel stenosis. Genetic ablation of Sca1+ cells attenuated venous arterialization and impaired vascular structure normalization, and thus, resulting in less Malat1 down-regulation. Single cell sequencing further revealed a fibroblast-like phenotype of Sca1+ SPCs-derived SMCs. Protein array sequencing and in vitro assays revealed that SMC regeneration from Sca1+ SPCs was regulated by Malat1 through miR125a-5p/Stat3 signaling pathway. These findings delineate the critical role of Sca1+ SPCs in vascular remodeling and reveal that lncRNA Malat1 is a key regulator and might serve as a novel biomarker or potential therapeutic target for vascular diseases.


Subject(s)
RNA, Long Noncoding , Spinocerebellar Ataxias , Vascular Diseases , Animals , Mice , Cells, Cultured , Disease Models, Animal , Muscle, Smooth, Vascular , Myocytes, Smooth Muscle/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Spinocerebellar Ataxias/metabolism , Stem Cells/metabolism , Vascular Diseases/metabolism , Vascular Remodeling/genetics
9.
Biomater Res ; 27(1): 6, 2023 Feb 03.
Article in English | MEDLINE | ID: mdl-36737833

ABSTRACT

BACKGROUND: Post-traumatic massive hemorrhage demands immediately available first-aid supplies with reduced operation time and good surgical compliance. In-situ crosslinking gels that are flexibly adapting to the wound shape have a promising potential, but it is still hard to achieve fast gelation, on-demand adhesion, and wide feasibility at the same time. METHODS: A white-light crosslinkable natural milk-derived casein hydrogel bioadhesive is presented for the first time. Benefiting from abundant tyrosine residues, casein hydrogel bioadhesive was synthesized by forming di-tyrosine bonds under white light with a ruthenium-based catalyst. We firstly optimized the concentration of proteins and initiators to achieve faster gelation and higher mechanical strength. Then, we examined the degradation, cytotoxicity, tissue adhesion, hemostasis, and wound healing ability of the casein hydrogels to study their potential to be used as bioadhesives. RESULT: Rapid gelation of casein hydrogel is initiated with an outdoor flashlight, a cellphone flashlight, or an endoscopy lamp, which facilitates its usage during first-aid and minimally invasive operations. The rapid gelation enables 3D printing of the casein hydrogel and excellent hemostasis even during liver hemorrhage due to section injury. The covalent binding between casein and tissue enables robust adhesion which can withstand more than 180 mmHg blood pressure. Moreover, the casein-based hydrogel can facilitate post-traumatic wound healing caused by trauma due to its biocompatibility. CONCLUSION: Casein-based bioadhesives developed in this study pave a way for broad and practical application in emergency wound management.

10.
Biomater Adv ; 145: 213244, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36549150

ABSTRACT

Infection can disturb the wound healing process and lead to poor skin regeneration, chronic wound, septicemia and even death. To combat the multi-drug resistance bacteria or fungi, it is urgent and necessary to develop advanced antimicrobial wound dressings. In this study, a composite hydrogel dressing composed of polyvinyl alcohol (PVA), agarose, glycerol and antibacterial hyperbranched polylysine (HBPL) was prepared by a freeze-thawing method. The hydrogel showed robust mechanical properties, and the HBPL in the hydrogel displayed effective and broad-spectrum antimicrobial properties to bacteria and fungi as well as biofilms. The composite hydrogel exhibited good biocompatibility with respect to the levels of cells, blood, tissue and main organs. In an animal experiment of an infected wound model, the hydrogel significantly eliminated the infection and accelerated the wound regeneration with better tissue morphology and angiogenesis. The hydrogel also successfully achieved scalable production of over 600 g with a yield over 90 %, suggesting the great potential for the application in practice.


Subject(s)
Anti-Infective Agents , Hydrogels , Animals , Hydrogels/pharmacology , Wound Healing , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bandages , Anti-Infective Agents/pharmacology
11.
ACS Nano ; 16(11): 19087-19095, 2022 11 22.
Article in English | MEDLINE | ID: mdl-36343336

ABSTRACT

Allomelanin is a class of nitrogen-free melanin mostly found in fungi and, like all naturally occurring melanins, is hydrophilic. Herein, we develop a facile method to modify synthetic hydrophilic allomelanin to yield hydrophobic derivatives through post-synthetic modifications. Amine-functionalized molecules of various kinds can be conjugated to allomelanin nanoparticles under mild conditions with high loading efficiencies. Hydrophobicity is conferred by introducing amine-terminated alkyl groups with different chain lengths. We demonstrate that the resulting hydrophobic allomelanin nanoparticles undergo air/water interfacial self-assembly in a controlled fashion, which enables the generation of large-scale and uniform structural colors. This work provides an efficient and tunable surface chemistry modification strategy to broaden the scope of synthetic melanin structure and function beyond the known diversity found in nature.


Subject(s)
Melanins , Nanoparticles , Melanins/chemistry , Hydrophobic and Hydrophilic Interactions , Nanoparticles/chemistry , Water/chemistry , Amines
12.
Cell Mol Life Sci ; 79(11): 576, 2022 Oct 31.
Article in English | MEDLINE | ID: mdl-36315271

ABSTRACT

RATIONALE: CD34+ cells are believed being progenitors that may be used to treat cardiovascular disease. However, the exact identity and the role of CD34+ cells in physiological and pathological conditions remain unclear. METHODS: We performed single-cell RNA sequencing analysis to provide a cell atlas of normal tissue/organ and pathological conditions. Furthermore, a genetic lineage tracing mouse model was used to investigate the role of CD34+ cells in angiogenesis and organ fibrosis. RESULTS: Single-cell RNA sequencing analysis revealed a heterogeneous population of CD34+ cells in both physiological and pathological conditions. Using a genetic lineage tracing mouse model, we showed that CD34+ cells not only acquired endothelial cell fate involved in angiogenesis, but also, CD34+ cells expressing Pi16 may transform into myofibroblast and thus participate in organ fibrosis. CONCLUSION: A heterogeneous CD34+ cells serve as a contributor not only to endothelial regeneration but also a wound healing response that may provide therapeutic insights into fibrosis.


Subject(s)
Endothelial Cells , Myofibroblasts , Mice , Animals , Fibrosis , Cell Differentiation , Endothelial Cells/pathology , Myofibroblasts/pathology , Wound Healing/physiology , Antigens, CD34
13.
Angew Chem Int Ed Engl ; 60(32): 17464-17471, 2021 08 02.
Article in English | MEDLINE | ID: mdl-33913253

ABSTRACT

Melanosomes in nature have diverse morphologies, including spheres, rods, and platelets. By contrast, shapes of synthetic melanins have been almost entirely limited to spherical nanoparticles with few exceptions produced by complex templated synthetic methods. Here, we report a non-templated method to access synthetic melanins with a variety of architectures including spheres, sheets, and platelets. Three 1,8-dihydroxynaphthalene dimers (4-4', 2-4' and 2-2') were used as self-assembling synthons. These dimers pack to form well-defined structures of varying morphologies depending on the isomer. Specifically, distinctive ellipsoidal platelets can be obtained using 4-4' dimers. Solid-state polymerization of the preorganized dimers generates polymeric synthetic melanins while maintaining the initial particle morphologies. This work provides a new route to anisotropic synthetic melanins, where the building blocks are preorganized into specific shapes, followed by solid-state polymerization.


Subject(s)
Coloring Agents/chemistry , Naphthols/chemistry , Polymers/chemistry , Anisotropy , Coloring Agents/chemical synthesis , Naphthols/chemical synthesis , Polymerization , Polymers/chemical synthesis
14.
J Am Chem Soc ; 143(10): 4005-4016, 2021 03 17.
Article in English | MEDLINE | ID: mdl-33673734

ABSTRACT

Melanin is a ubiquitous natural pigment found in a diverse array of organisms. Allomelanin is a class of nitrogen-free melanin often found in fungi. Herein, we find artificial allomelanin analogues exhibit high intrinsic microporosity and describe an approach for further increasing and tuning that porosity. Notably, the synthetic method involves an oxidative polymerization of 1,8-DHN in water, negating the need for multiple complex templating steps and avoiding expensive or complex chemical precursors. The well-defined morphologies of these nanomaterials were elucidated by a combination of electron microscopy and scattering methods, yielding to high-resolution 3D reconstruction based on small-angle X-ray scattering (SAXS) results. Synthetic allomelanin nanoparticles exhibit high BET areas, up to 860 m2/g, and are capable of ammonia capture up to 17.0 mmol/g at 1 bar. In addition, these nanomaterials can adsorb nerve agent simulants in solution and as a coating on fabrics with high breathability where they prevent breakthrough. We also confirmed that naturally derived fungal melanin can adsorb nerve gas simulants in solution efficiently despite lower porosity than synthetic analogues. Our approach inspires further analysis of yet to be discovered biological materials of this class where melanins with intrinsic microporosity may be linked to evolutionary advantages in relevant organisms and may in turn inspire the design of new high surface area materials.


Subject(s)
Biopolymers/chemistry , Melanins/chemistry , Adsorption , Biopolymers/metabolism , Fungi/metabolism , Melanins/metabolism , Nanoparticles/chemistry , Naphthols/chemistry , Naphthols/metabolism , Paraoxon/chemistry , Paraoxon/metabolism , Porosity , Scattering, Small Angle , X-Ray Diffraction
15.
Free Radic Biol Med ; 165: 324-333, 2021 03.
Article in English | MEDLINE | ID: mdl-33556462

ABSTRACT

Perivascular tissue including adipose layer and adventitia have been considered to play pivotal roles in vascular development and disease progression. Recent studies showed that abundant stem/progenitorcells (SPCs) are present in perivascular tissues. These SPCs exhibit capability to proliferate and differentiate into specific terminal cells. Adult perivascular SPCs are quiescent in normal condition, once activated by specific molecules (e.g., cytokines), they migrate toward the lumen side where they differentiate into both smooth muscle cells (SMCs) and endothelial cells (ECs), thus promoting intima hyperplasia or endothelial regeneration. In addition, perivascular SPCs can also regulate vascular diseases via other ways including but not limited to paracrine effects, matrix protein modulation and microvessel formation. Perivascular SPCs have also been shown to possess therapeutic potentials due to the capability to differentiate into vascular cells and regenerate vascular structures. This review summarizes current knowledge on resident SPCs features and discusses the potential benefits of SPCs therapy in vascular diseases.


Subject(s)
Endothelial Cells , Vascular Diseases , Humans , Myocytes, Smooth Muscle , Regeneration , Stem Cells , Vascular Diseases/therapy
16.
J Am Chem Soc ; 143(7): 2622-2637, 2021 02 24.
Article in English | MEDLINE | ID: mdl-33560127

ABSTRACT

Melanin is ubiquitous in living organisms across different biological kingdoms of life, making it an important, natural biomaterial. Its presence in nature from microorganisms to higher animals and plants is attributed to the many functions of melanin, including pigmentation, radical scavenging, radiation protection, and thermal regulation. Generally, melanin is classified into five types-eumelanin, pheomelanin, neuromelanin, allomelanin, and pyomelanin-based on the various chemical precursors used in their biosynthesis. Despite its long history of study, the exact chemical makeup of melanin remains unclear, and it moreover has an inherent diversity and complexity of chemical structure, likely including many functions and properties that remain to be identified. Synthetic mimics have begun to play a broader role in unraveling structure and function relationships of natural melanins. In the past decade, polydopamine, which has served as the conventional form of synthetic eumelanin, has dominated the literature on melanin-based materials, while the synthetic analogues of other melanins have received far less attention. In this perspective, we will discuss the synthesis of melanin materials with a special focus beyond polydopamine. We will emphasize efforts to elucidate biosynthetic pathways and structural characterization approaches that can be harnessed to interrogate specific structure-function relationships, including electron paramagnetic resonance (EPR) and solid-state nuclear magnetic resonance (ssNMR) spectroscopy. We believe that this timely Perspective will introduce this class of biopolymer to the broader chemistry community, where we hope to stimulate new opportunities in novel, melanin-based poly-functional synthetic materials.


Subject(s)
Melanins/chemistry , Electron Spin Resonance Spectroscopy , Indoles/chemistry , Indoles/metabolism , Magnetic Resonance Spectroscopy , Melanins/biosynthesis , Molecular Conformation , Polymers/chemistry , Polymers/metabolism
17.
Stem Cell Res Ther ; 12(1): 67, 2021 01 19.
Article in English | MEDLINE | ID: mdl-33468212

ABSTRACT

BACKGROUND: As the most important component of the vascular wall, vascular smooth muscle cells (VSMCs) participate in the pathological process by phenotype transformation or differentiation from stem/progenitor cells. The main purpose of this study was to reveal the role and related molecular mechanism of microRNA-30c-5p (miR-30c-5p) in VSMC differentiation from adventitial progenitor cells expressing stem cell antigen-1(Sca-1). METHODS: In this study, we detected the expression of miR-30c-5p in human normal peripheral arteries and atherosclerotic arteries. In vitro, a stable differentiation model from adventitial Sca-1+ progenitor cells to VSMCs was established using transforming growth factor-ß1 (TGF-ß1) induction and the expression of miR-30c-5p during the process was observed. Then, we explored the effect of miR-30c-5p overexpression and inhibition on the differentiation from adventitial Sca-1+ progenitor cells to VSMCs. The target genes of miR-30c-5p were identified by protein chip and biological analyses and the expression of these genes in the differentiation process were detected. Further, the relationship between the target gene and miR-30c-5p and its effect on differentiation were evaluated. Finally, the co-transfection of miR-30c-5p inhibitor and small interfering RNA (siRNA) of the target gene was implemented to verify the functional target gene of miR-30c-5p during the differentiation from adventitial Sca-1+ progenitor cells to VSMCs, and the dual-luciferase reporter gene assay was performed to detect whether the mRNA 3'untranslated region (UTR) of the target gene is the direct binding site of miR-30c-5p. RESULTS: The expression of miR-30c-5p in the human atherosclerotic arteries was significantly lower than that in the normal arteries. During the differentiation from adventitial Sca-1+ progenitor cells to VSMCs, the expression of VSMC special markers including smooth muscle α-actin (SMαA), smooth muscle-22α (SM22α), smooth muscle myosin heavy chain (SMMHC), and h1-caponin increased accompanied with cell morphology changing from elliptic to fusiform. Meanwhile, the expression of miR-30c-5p decreased significantly. In functional experiments, overexpression of miR-30c-5p inhibited SMαA, SM22α, SMMHC, and h1-caponin at the mRNA and protein levels. In contrast, inhibition of miR-30c-5p promoted the expression of SMαA, SM22α, SMMHC, and h1-caponin. The target gene, osteoprotegerin (OPG), was predicted through protein chip and bioinformatics analyses. Overexpression of miR-30c-5p inhibited OPG expression while inhibition of miR-30c-5p had an opposite effect. Co-transfection experiments showed that low expression of OPG could weaken the promotion effect of miR-30c-5p inhibitor on the differentiation from adventitial Sca-1+ progenitor cells to VSMCs and the dual-luciferase reporter gene assay demonstrated that miR-30c-5p could target the mRNA 3'UTR of OPG directly. CONCLUSIONS: This study demonstrates that miR-30c-5p expression was significantly decreased in atherosclerotic arteries and miR-30c-5p inhibited VSMC differentiation from adventitial Sca-1+ progenitor cells through targeting OPG, which may provide a new target for the treatment of VSMCs-associated diseases.


Subject(s)
MicroRNAs , Muscle, Smooth, Vascular , Cell Differentiation , Cell Proliferation , Cells, Cultured , Humans , MicroRNAs/genetics , Myocytes, Smooth Muscle , Osteoprotegerin , Stem Cells
18.
ACS Cent Sci ; 6(7): 1179-1188, 2020 Jul 22.
Article in English | MEDLINE | ID: mdl-32724852

ABSTRACT

Human hair is naturally colored by melanin pigments, which afford myriad colors from black, to brown, to red depending on the chemical structures and specific blends. In recent decades, synthetic efforts have centered on dopamine oxidation to polydopamine, an effective eumelanin similar to the one found in humans. To date, only a few attempts at polydopamine deposition on human hair have been reported, and their translation to widespread usage and potential commercialization is still hampered by the harsh conditions employed. We reasoned that novel, mild, biocompatible approaches could be developed to establish a metal-free route to tunable, nature-inspired, long-lasting coloration of human hair. Herein, we describe synthetic and formulation routes to achieving this goal and show efficacy on a variety of human hair samples via multiple spectroscopic and imaging techniques. Owing to the mild and inexpensive conditions employed, this novel approach has the potential to replace classical harsh hair dyeing conditions that have raised concerns for several decades due to their potential toxicity.

19.
J Am Chem Soc ; 142(29): 12802-12810, 2020 07 22.
Article in English | MEDLINE | ID: mdl-32638590

ABSTRACT

Melanins are a family of heterogeneous biopolymers found ubiquitously across plant, animal, bacterial, and fungal kingdoms where they act variously as pigments and as radiation protection agents. There exist five multifunctional yet structurally and biosynthetically incompletely understood varieties of melanin: eumelanin, neuromelanin, pyomelanin, allomelanin, and pheomelanin. Although eumelanin and allomelanin have been the focus of most radiation protection studies to date, some research suggests that pheomelanin has a better absorption coefficient for X-rays than eumelanin. We reasoned that if a selenium enriched melanin existed, it would be a better X-ray protector than the sulfur-containing pheomelanin because the X-ray absorption coefficient is proportional to the fourth power of the atomic number (Z). Notably, selenium is an essential micronutrient, with the amino acid selenocysteine being genetically encoded in 25 natural human proteins. Therefore, we hypothesize that selenomelanin exists in nature, where it provides superior ionizing radiation protection to organisms compared to known melanins. Here we introduce this novel selenium analogue of pheomelanin through chemical and biosynthetic routes using selenocystine as a feedstock. The resulting selenomelanin is a structural mimic of pheomelanin. We found selenomelanin effectively prevented neonatal human epidermal keratinocytes (NHEK) from G2/M phase arrest under high-dose X-ray irradiation. Provocatively, this beneficial role of selenomelanin points to it as a sixth variety of yet to be discovered natural melanin.


Subject(s)
Melanins/chemistry , Organoselenium Compounds/chemistry , Selenium/chemistry , Humans , Keratinocytes/drug effects , Melanins/pharmacology , Molecular Structure , Organoselenium Compounds/chemical synthesis , Organoselenium Compounds/pharmacology , Particle Size , Selenium/pharmacology , Surface Properties , X-Rays
20.
Angew Chem Int Ed Engl ; 59(43): 19136-19142, 2020 10 19.
Article in English | MEDLINE | ID: mdl-32659039

ABSTRACT

Herein, we report the photoinitiated polymerization-induced self-assembly (photo-PISA) of spherical micelles consisting of proapoptotic peptide-polymer amphiphiles. The one-pot synthetic approach yielded micellar nanoparticles at high concentrations and at scale (150 mg mL-1 ) with tunable peptide loadings up to 48 wt. %. The size of the micellar nanoparticles was tuned by varying the lengths of hydrophobic and hydrophilic building blocks. Critically, the peptide-functionalized nanoparticles imbued the proapoptotic "KLA" peptides (amino acid sequence: KLAKLAKKLAKLAK) with two key properties otherwise not inherent to the sequence: 1) proteolytic resistance compared to the oligopeptide alone; 2) significantly enhanced cell uptake by multivalent display of KLA peptide brushes. The result was demonstrated improved apoptosis efficiency in HeLa cells. These results highlight the potential of photo-PISA in the large-scale synthesis of functional, proteolytically resistant peptide-polymer conjugates for intracellular delivery.


Subject(s)
Apoptosis , Light , Nanoparticles/chemistry , Peptides/chemistry , Polymers/chemistry , Amino Acid Sequence , Cell Survival/drug effects , HeLa Cells , Humans , Hydrophobic and Hydrophilic Interactions , Micelles , Polymerization
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