Messenger RNA is a novel therapeutic modality which was key in curbing the Covid-19 pandemic. However, the delivery of mRNA in cells requires the development of smart vectors. We here report on amphiphilic dynamic covalent polymers formed in situ through RNA templating, and show effective nanoparticle formation and delivery of EGFP mRNA in cells.
Bone regeneration is one of the most effective methods for treating bone defects. In this work, tricarboxylic cellulose/sodium alginate loaded with hydroxyapatite (HA) and/or graphene oxide (GO) was coagulated by calcium ions to create beads as scaffolds. In the first, cellulose was oxidized to water-soluble tricarboxylic cellulose (TCC) by 2,2,6,6‐tetramethylpiperidine-1-oxyl (TEMPO), periodate, and chlorite oxidation. HA was extracted from eggshells via microwave treatment, and GO was synthesized using the Hummer method. The structural behavior of the formed beads was meticulously investigated through various characterization techniques such as Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The SEM images confirmed the formation of particles of micrometric size without any specific morphology. Incorporating GO or HA does not affect the morphologies of the materials on the micrometric scale. The cytocompatibility of different bead preparations was studied on murine mesenchymal stem cells. Moreover, the swellability in water and biodegradability by cellulase enzyme of prepared beads were studied. The results show that the prepared beads may be promising for bone tissue engineering.
We report the synthesis of multifunctional periodic mesoporous organosilica nanoparticles (PMO NPs) with substantial two-photon absorption properties and targeting capability for two-photon excitation fluorescence (TPEF) and photodynamic therapy (TPE-PDT). Prepared using an adapted sol-gel synthesis, the nanoplatforms integrated two silylated chromophores in their three-dimensional matrix to maximize non-radiative Förster resonance energy transfer from a high two-photon absorption fluorophore donor to a porphyrin derivative acceptor, leading to an enhanced generation of reactive oxygen species. Combinations of biodegradable and non-biodegradable bis(triethoxysilyl)alkoxysilanes were employed for the synthesis of the NPs, and the corresponding photophysical studies revealed high efficiency levels of FRET. Next, the cellular uptake and toxicities of pristine and functionalized NPs were evaluated on breast cancer cell lines upon TPEF and TPE-PDT. Notably, the use of TPE-PDT treatment led to high levels of phototoxicity on MCF-7 and MDA-MB-231 cancer cells with substantial effects when compared to one-photon excitation (OPE)-PDT treatment. Preliminary in vivo data on selective and biodegradable NPs showed a significant phototoxicity towards MDA-MB-231 on zebrafish xenograft embryos, making these advanced nanoplatforms promising candidates for future TPE-PDT-based cancer treatments.
This work investigates the electron-donating capabilities of two 10-pi electron nitrogen bridgehead bicyclic [5,6]-fused ring systems, imidazo[1,2-a]pyridine and imidazo[1,5-a]pyridine rings. Eight compounds with varying positions of electron-withdrawing moieties (TCF or DCI) coupled to the imidazopyridine ring were synthesized and studied. DCI-containing compounds (Ib-IVb) exhibited a purely dipolar nature with broad absorption bands, weak fluorescence, large Stokes shifts, and strong solvatochromism. In contrast, TCF-containing compounds (Ia-IVa) demonstrated diverse properties. Imidazo[1,2-a]pyridine derivatives Ia and IIa were purely dipolar, while imidazo[1,5-a]pyridine derivatives IIIa and IVa displayed a cyanine-like character with intense absorption and higher quantum yields of emission. The observed gradual red shift in optical properties with changing electron-donor groups (IIb < Ib < IIIb < IVb) and (IIa < Ia < IIIa < IVa) underscores the stronger electron-donor character of imidazo[1,5-a]pyridine compared to that of imidazo[1,2-a]pyridine. Furthermore, crystalline powders of imidazo[1,2-a]pyridine derivatives exhibited fluorescence despite minimal emission in solution. Two compounds (Ib and IVa) were successfully formulated into nanoparticles for potential in vivo imaging applications in zebrafish embryos.
This work introduces rationally designed, improved amphiphilic single-chain polymer nanoparticles (SCNPs) for imaging and photodynamic therapy (PDT) in zebrafish embryo xenografts. SCNPs are ultrasmall polymeric nanoparticles with sizes similar to proteins, making them ideal for biomedical applications. Amphiphilic SCNPs result from the self-assembly in water of isolated synthetic polymeric chains through intrachain hydrophobic interactions, mimicking natural biomacromolecules and, specially, proteins (in size and when loaded with drugs, metal ions or fluorophores also in function). These ultrasmall, soft nanoparticles have various applications, including catalysis, sensing, and nanomedicine. Initial in vitro experiments with nonfunctionalized, amphiphilic SCNPs loaded with a photosensitizing Zn phthalocyanine with four nonperipheral isobutylthio substituents, ZnPc, showed promise for PDT. Herein, the preparation of improved, amphiphilic SCNPs containing ZnPc as highly efficient photosensitizer encapsulated within the nanoparticle and surrounded by anthracene units is disclosed. The amount of anthracene groups and ZnPc molecules within each single-chain nanoparticle controls the imaging and PDT properties of these nanocarriers. Critically, this work opens the way to improved PDT applications based on amphiphilic SCNPs as a first step toward ideal, long-term artificial photo-oxidases (APO).
Zwitterionic silica coatings for surface functionalization are greatly prominent because of their simple and fast preparation, high availability, and effective antifouling properties. In this work, two zwitterionic sulfobetaine silane coatings, i.e., mono-SBSi and tris-SBSi, were deposited on glass surfaces and tested for antifouling of biological material and biofilm using human cancer cell and seawater, respectively. The used zwitterionic precursors mono-SBSi and tris-SBSi differ by the number of hydrolyzable silane groups: mono-SBSi contains one trimethoxysilane group, whereas tris-SBSi contains three of these functions. First, X-ray photoelectron spectroscopy indicates the successful grafting of zwitterionic coatings onto a glass surface. Characterization using atomic force microscopy shows the different morphologies and roughness of the two coatings. The glass surface became more hydrophilic after the grafting of zwitterionic coatings than the bare glass substrate. The antifouling properties of two coatings were evaluated via human cancer cell adsorption. Interestingly, the tris-SBSi coating displays a significantly lower level of cell adsorption compared to that of both mono-SBSi coating and the non-modified control surface. The same trend was observed for biofilm formation in seawater. Finally, the toxicity of mono-SBSi and tris-SBSi coatings was evaluated on zebrafish embryos, indicating the good biocompatibility of both coatings. Our results indicate interesting antifouling properties of zwitterionic coatings. The chemical constitution of the used precursor has an impact on the antifouling properties of the formed coating: the tris-SBSi-based zwitterionic silica coatings display improved antifouling properties compared to those of the mono-SBSi-based coating. Besides, the use of trisilylated precursors should result in the formation of more resistant and robust coatings due to the higher number of grafting functions. For all these reasons, we anticipate that tris-SBSi coatings will open new perspectives for antifouling applications for biological environments and implants.
The development of photodynamic therapy requires access to smart photosensitizers which combine appropriate photophysical and biological properties. Interestingly, supramolecular and dynamic covalent chemistries have recently shown their ability to produce novel architectures and responsive systems through simple self-assembly approaches. Herein, we report the straightforward formation of porphyrin-peptide conjugates and cage compounds which feature on their surface chemical groups promoting cell uptake and specific organelle targeting. We show that they self-assemble, in aqueous media, into positively-charged nanoparticles which generate singlet oxygen upon green light irradiation, while also undergoing a chemically-controlled disassembly due to the presence of reversible covalent linkages. Finally, the biological evaluation in cells revealed that they act as effective photosensitizers and promote synergistic effects in combination with Doxorubicin.
Inducing the degradation of pathological soluble antigens could be the key to greatly enhancing the efficacy of therapeutic monoclonal antibodies (mAbs), extensively used in the treatment of autoimmune and inflammatory disorders or cancer. Lysosomal targeting has gained increasing interest in recent years due to its pharmaceutical applications far beyond the treatment of lysosomal diseases, as a way to address proteins to the lysosome for eventual degradation. Mannose 6-phosphonate derivatives (M6Pn), called AMFA, are unique glycovectors that can significantly enhance the cellular internalization of the proteins conjugated to AMFA via the cation-independent mannose 6-phosphate receptor (M6PR) pathway. AMFA engineering of mAbs results in the generation of a bifunctional antibody that is designed to bind both the antigen and the M6PR. The improvement of the therapeutic potential by AMFA engineering was investigated using two antibodies directed against soluble antigens: infliximab (IFX), directed against tumor necrosis factor α (TNF-α), and bevacizumab (BVZ), directed against the vascular endothelial growth factor (VEGF). AMFA conjugations to the antibodies were performed either on the oligosaccharidic chains of the antibodies or on the lysine residues. Both conjugations were controlled and reproducible and provided a novel affinity for the M6PR without altering the affinity for the antigen. The grafting of AMFA to mAb increased their cellular uptake through an M6PR-dependent mechanism. The antigens were also 2.6 to 5.7 times more internalized by mAb-AMFA and rapidly degraded in the cells. Additional cell culture studies also proved the significantly higher efficacy of IFX-AMFA and BVZ-AMFA compared to their unconjugated counterparts in inhibiting TNF-α and VEGF activities. Finally, studies in a zebrafish embryo model of angiogenesis and in xenografted chick embryos showed that BVZ-AMFA was more effective than BVZ in reducing angiogenesis. These results demonstrate that AMFA grafting induces the degradation of soluble antigens and a significant increase in the therapeutic efficacy. Engineering with mannose 6-phosphate analogues has the potential to develop a new class of antibodies for autoimmune and inflammatory diseases.
A series of thiochromenocarbazole imide (TCI) photosensitizers featuring carbonic anhydrase inhibitors (CAi) was designed to alleviate the consequences of PDT-induced hypoxia by merging the advantages of hCA IX knockdowns with PDT.
Herein, we report the design, the synthesis, and the study of novel triphenyl phosphonium-based nucleoside conjugates. 2'-Deoxycytidine was chosen as nucleosidic cargo, as it allows the introduction of fluorescein on the exocyclic amine of the nucleobase and grafting of the vector was envisaged through the formation of a biolabile ester bond with the hydroxyl function at the 5'-position. Compound 3 was identified as a potential nucleoside prodrug, showing ability to be internalized efficiently into cells and to be co-localized with mitochondria.
Two different poly(benzylmalate) biopolymers, a hydrophobic non-PEGylated (PMLABe(73)) and an amphiphilic PEGylated derivative (PEG(42)-b-PMLABe(73)), have been used to encapsulate a phthalocyanine chosen for its substitution pattern that is highly suitable for photodynamic therapy. Different phthalocyanine/(co)polymers ratios have been used for the nanoprecipitation. A set of six nanoparticles has been obtained. If the amphiphilic PEGylated copolymer proved to be slightly more efficient for the encapsulation and to lower the aggregation of the phthalocyanine inside the nanoparticles, it is, however, the hydrophobic PMLABe(73)-based nanoparticles that exhibited the best photodynamic efficiency.
Targeted degradation of pathological proteins is a promising approach to enhance the effectiveness of therapeutic monoclonal antibodies (mAbs) in cancer therapy. In this study, we demonstrate that this objective can be efficiently achieved by the grafting of mannose 6-phosphate analogues called AMFAs2 onto the therapeutic antibodies trastuzumab and cetuximab, both directed against membrane antigens. The grafting of AMFAs confers to these antibodies the novel property of being internalized via the mannose 6-phosphate receptor (M6PR) pathway. AMFA conjugation to these mAbs significantly increases their cellular uptake and leads to enhanced degradation of the target antigens in cancer cells. This results in a drastic inhibition of cancer cell proliferation compared to unconjugated mAbs, as demonstrated in various cancer cell lines, and an increased therapeutic efficacy in mouse and zebrafish xenografted models. These findings highlight the potential of this technology to improve therapeutic outcomes in cancer treatment.
Phthalocyanines have been described as effective photosensitizers for photodynamic therapy and are therefore, being studied for their biomedical applications. The metalation of photosensitizers can improve their photodynamic therapy potential. Here, we focus on the biological properties of [1,4-Bis(3,6,9,12-Tetraoxatridec-1-yloxy)phthalocyaninato]zinc(II) (ZnPc(αEG4)2) and demonstrate its exceptional anticancer activity upon light stimulation to kill preferentially cancer cells with a start of efficiency at 10 pM. Indeed, in this work we highlighted the high selectivity of ZnPc(αEG4)2 for cancer cells compared with healthy ones and we establish its mechanism of action, enabling us to conclude that ZnPc(αEG4)2 could be a powerful tool for cancer therapy.
Considering the bioactive composition and therapeutic interest of Ficus carica, much research has been conducted on its fruits and leaves. However, there has been relatively little investigation regarding the wood bark, despite its potential as a rich source of phytochemical compounds with diverse biological activities. The aim of this work is the determination of the phenolic composition of the wood bark extracts of F. carica from three cultivars (Aberkane, Aghanime, and Bakour) and the assessment of their potential cytotoxicity and bioactive capacities such as antioxidant, anticancer, and anti-inflammatory activities. The phytochemical compounds were identified and quantified using UPLC-ESI-MS. The results revealed that Aberkane wood bark cultivar had the highest content of total polyphenols and ascorbic acid, while Aghanime cultivar had the highest content of flavonoids. The wood bark of the Aberkane cultivar exhibited the highest DPPH and ABTS scavenging activities (48.55
In the present work, superparamagnetic adsorbents based on 3-aminopropyltrimethoxy silane (APTMS)-coated maghemite (γFe2O3@SiO2–NH2) and cobalt ferrite (CoFe2O4@SiO2–NH2) nanoparticles were prepared and characterized using transmission-electron microscopy (TEM/HRTEM/EDXS), Fourier-transform infrared spectroscopy (FTIR), specific surface-area measurements (BET), zeta potential (ζ) measurements, thermogravimetric analysis (TGA), and magnetometry (VSM). The adsorption of Dy3+, Tb3+, and Hg2+ ions onto adsorbent surfaces in model salt solutions was tested. The adsorption was evaluated in terms of adsorption efficiency (%), adsorption capacity (mg/g), and desorption efficiency (%) based on the results of inductively coupled plasma optical emission spectrometry (ICP-OES). Both adsorbents, γFe2O3@SiO2–NH2 and CoFe2O4@SiO2–NH2, showed high adsorption efficiency toward Dy3+, Tb3+, and Hg2+ ions, ranging from 83% to 98%, while the adsorption capacity reached the following values of Dy3+, Tb3+, and Hg2+, in descending order: Tb (4.7 mg/g) > Dy (4.0 mg/g) > Hg (2.1 mg/g) for γFe2O3@SiO2–NH2; and Tb (6.2 mg/g) > Dy (4.7 mg/g) > Hg (1.2 mg/g) for CoFe2O4@SiO2–NH2. The results of the desorption with 100% of the desorbed Dy3+, Tb3+, and Hg2+ ions in an acidic medium indicated the reusability of both adsorbents. A cytotoxicity assessment of the adsorbents on human-skeletal-muscle derived cells (SKMDCs), human fibroblasts, murine macrophage cells (RAW264.7), and human-umbilical-vein endothelial cells (HUVECs) was conducted. The survival, mortality, and hatching percentages of zebrafish embryos were monitored. All the nanoparticles showed no toxicity in the zebrafish embryos until 96 hpf, even at a high concentration of 500 mg/L.
The increased importance of RNA-based therapeutics comes with a need to develop next-generation stimuli-responsive systems capable of binding, transporting and releasing RNA oligomers. In this work, we describe triazolium-based amphiphiles capable of siRNA binding and enzyme-responsive release of the nucleic acid payload. In aqueous medium, the amphiphile self-assembles into nanocarriers that can disintegrate upon the addition of esterase. Key to the molecular design is a self-immolative linker that is anchored to the triazolium moiety and acts as a positively-charged polar head group. We demonstrate that addition of esterase leads to a degradation cascade of the linker, leaving the neutral triazole compound unable to form complexes and therefore releasing the negatively-charged siRNA. The reported molecular design and overall approach may have broad utility beyond this proof-of-principle study, because the underlying CuAAC "click" chemistry allows bringing together three groups very efficiently as well as cleaving off one of the three groups under the mild action of an esterase enzyme.
Periodic Mesoporous Ionosilica Nanoparticles (PMINPs) made via co-condensation reactions starting from an ionosilica precursor and a porphyrin derivative were used for simultaneous BODIPY/siRNA delivery in cancer cells. We observed high BODIPY loading capacities and efficiencies of the PMINPs that are triggered by anion exchange. siRNA adsorption took place on the surface of the nanoparticles, whereas BODIPY was encapsulated within the core of the nanoparticles. BODIPY release was found to be pH-dependent. Our results indicate 94 % BODIPY release after 16 h at pH 4, whereas only 2 % were released at pH 7.4. Furthermore, complexation with siRNA against luciferase gene was observed at the surface of PMINPs and gene silencing through its delivery via photochemical internalization (PCI) mechanism was efficient in MDA-MB-231 breast cancer cells expressing stable luciferase.
Herein, we report the successful multi-step syntheses of new two-photon responsive octupolar-shaped fluorophores with pendant propanol groups, abbreviated as F1 and F2. Mass spectrometry and 1H NMR measurements confirmed they were pure and isolated. This type of compounds has already proven good biocompatibility and internalization in HEK293 cells, as well as high two-photon absorption cross-sections in the near infra-red region, which are interesting aspects for bioapplications 1. Thus, they can serve as two-photon bioimaging markers. In addition, we studied the potential of F1 fluorophore as a donor in Fӧrster Resonance Energy Transfer (FRET) with tetraaminophenylporphyrin acceptor (POR). The porphyrin photosensitizer already displayed significant efficiency in anticancer Two-Photon Excited Photodynamic Therapy (TPE-DPT) when integrated in Periodic Mesoporous Organosilica Nanoparticles (PMO NPs), due to J-aggregations inside the mesostructured that are enhancing the two-photon absorption properties of the material 2-3.Thus, the trisilylated F1 and the tetrasilylated POR were both integrated in the sol-gel synthesis of PMO alongside with ethylene (E) or ethenylene (ENE)-based organoalkoxysilane precursors. Biodegradable PMO (BPMO) made of bis(triethoxysilyl)propyl)tetrasulfide (4S) were also prepared, with a 80:20 E:4S or ENE:4S molar ratio, in order to compare their therapeutic capability. Glutathione, a biomolecule responsible for redox cleavage of S-S bonds, is present in high rates at bacteria membrane interface and inside cancer cells, leading to BPMO biodegradation 4. Moreover, PMO and BPMO physico-chemical properties being noticeably different (morphology, surface charge, porosity), it could affect positively or negatively the two-photon absorption properties and 1O2 transport in the systems. Next, NPs were further modified with PEG-silane to bring better colloidal stability and biocompatibility. In a final step, they were post-grafted with a squarate mannose derivative (sqMAN) through primary amine function of previously functionalized aminoundecyltriethoxysilane. This mannoside presents numerous advantages: an active targeting of lectins over-expressed by cancer cells, facilitating nanoparticle internalization 5, and spontaneous interaction with type 1 fimbrial H lectins of bacteria, inhibiting their infection of host cells 6-7. Moreover, high sqMAN concentration can induce bacteria aggregation, thus considerably reducing their proliferation. Naked F1-POR-E BPMO induced significant mortality of MCF-7 cancer cells by TPE-PDT when irradiated at 780 or 860 nm. The different PMO (E, ENE) and BPMO (E-4S, ENE-4S), grafted or not with PEG and sqMAN, will be compared together to assess the best therapeutic conditions. Silica-based NPs are suitable carriers for protecting drugs against chemical and enzymatic degradation, with potential controlled delivery and lower systemic/topical toxicity. With the objective to perform dual therapy (antibiotic delivery and antibacterial TPE-PDT), vancomycin hydrochloride antibiotic was loaded at the surface and in the pores of the F1-POR PMO NPs. With NPs displaying pH-dependent surface charge, the drug loading content were variable between pH 5 and 7 8. Vancomycin release was observed on E. coli and S. aureus strains with a total growth inhibition at concentrations 1-2 fold higher than the minimum inhibitory concentration (MIC).In perspective, those PMO and VAN-loaded PMO NPs would be used for in vivo antibacterial TPE-PDT and drug delivery for wound healing studies on mices, and also antitumoral TPE-PDT on zebrafish embryo with two-photon excited fluorescence tracking via fluorophore and porphyrin fluorescence.
In the face of the undesirable effects induced by anti-inflammatory drugs, there has been a return, nowadays, to the search for active ingredients based on plants. Herein, for the first time we study the anti-inflammatory activity of essential oils of three species of the genus Inula: Inula viscosa, Inula graveolens and Inula crithmoides in lipopolysaccharide (LPS)-activated macrophages. Essential oils have shown excellent preventive anti-inflammatory potential by causing inhibition of nitric oxide (NO) production in LPSactivated RAW264.7 macrophages with IC50s ranging between 15 and 35 µg mL− 1. On the other hand, the major acidic compounds, more precisely α- and β-costic acids, have been isolated from Inula viscosa and Inula graveolens essential oils and evaluated for their anti-inflammatory effect. These compounds appear to have a moderate preventive inhibitory effect on NO production relative to the significant effect generated by the neutral minority components present in the oils such as borneol, bornyl acetate, (E)-nerolidol, caryophyllene oxide, T-cadinol and eugenol. Therefore, we can deduce that the studied essential oils could be used as anti-inflammatory agents for the treatment of various inflammatory pathologies.