Molecular Pharmaceutics最新文献

Dissolving microneedles (MNs) hold promise as a versatile drug delivery platform, particularly suited to the delivery of complex molecules across the skin. Dissolving MNs are commonly manufactured using an accessible and reproducible two-step casting process. The selection of different polymers for both the needle and backing layer increases the adaptability of this platform. Previously, work has focused on the needle layer formulation and how the formulation will affect drug delivery. Less well understood is the role of the backing layer on insertion and, subsequently, drug delivery. Therefore, the aim of this work was to evaluate changes to the backing layer formulation on MN insertion and understand the relationships between material properties. The needle layer was formulated with polyvinylpyrrolidone-co-vinyl acetate, with and without insulin, a model protein therapeutic. A range of polymers was used to formulate the backing layer, including sodium carboxymethylcellulose (Na-CMC), poly(vinyl alcohol) (PVA), and polystyrene (PS). MNs manufactured with a PVA backing layer demonstrated an improved insertion profile (efficiency and depth). Permeation studies supported that the PVA backing layer offered an overall advantage in insulin delivery, with a cumulative recovery of 17.6% of the total insulin loading. This work demonstrates the importance of the backing layer formulation in MN arrays. Changing the backing layer formulation impacted both the insertion of MNs and subsequent drug delivery. Moving forward, the properties of polymers selected for use in MN backing layers should be thoroughly explored and rationally selected depending on the intended application.

Molecular dynamics (MD) simulations of ibuprofen nanocrystal dissolution in water reveal that spherical particles below the critical size (e.g., with radius, r = 20 Å) that are metastable, as predicted by classical nucleation theory (CNT), dissociate predominantly through a nonclassical mechanism whereby groups of molecules periodically detach and reattach themselves to the moisture-infiltrated, swollen particle. This behavior leads to oscillations in the dissolution profile and a generally poor fit to the Noyes–Whitney (N–W) equation. Conversely, larger particles (e.g., r = 60 Å), which are predicted to be thermodynamically stable per CNT, are more likely to exhibit classical N–W kinetics on the nanosecond time scale. In either case, crystallinity is lost very rapidly, within the first ∼20 ps of simulation time due to water intrusion into the lattice. For consistency, the single-particle dissolution kinetics are investigated at similar concentrations (ibuprofen/water, ∼17% w/w). Because saturation is expected in the long-time limit due to the poor water solubility of the drug, only the first 10 ns of dissolution time is used to quantitatively assess the kinetics where sink conditions are expected. The H-bonding count between ibuprofen and water molecules in each frame of the output MD trajectory is used as a surrogate measure of the extent of ibuprofen dissolution at each point in time, recognizing that it does not distinguish between particle swelling and the dissociation of ibuprofen molecules (or groups of molecules) from the particle surface. While larger particles appear to obey N–W kinetics, simulations presented herein demonstrate that they prefer to form and maintain interior pockets of water on the time scale of the simulations, rather than to dissolve completely in the traditional sense of that equation. This finding could have implications for the biorelevant dissolution behavior of poorly water-soluble drugs and drug delivery mechanisms of nanocrystal formulations.

In antitumor activities, baicalin and astragaloside IV inhibit tumor growth, induce cell death, and restrain metastasis in various cancers. Generally, a mixture of massive herbs like scutellaria or astragalus matches with other drugs to reach a curative effect in traditional Chinese prescription. Therefore, researchers aspire to an effective type of drug combination that shows promoted absorption and higher bioavailability in preclinical studies. Here, we report an optical method to detect chiral baicalin and astragaloside IV and also monitor the absorption of different chirals in ovarian cells. Eventually, R-Baicalin-Astragaloside IV dual drugs combination shows promoted absorption of each other compared with single chiral drugs or another. Based on the optical method results, we designed a series of in vitro and in vivo experiments to explain and analyze the mechanism of the curative effect. Therein, the result reveals that the tumor-associated neutrophils were reduced via the down-regulated TLR4/MYD88/NF-κB pathway to increased PD-1/PD-L1 immune response in epithelial ovarian cancer under the influence of R-Baicalin-Astragaloside IV. Thus, this work offers a comprehensive report on structure–activity relationships of chiral and dual drug strategies to improve its bioavailability in therapy of ovarian cancer.

Small extracellular vesicles (sEVs) can efficiently transfer payloads, such as nucleic acids, into the cytosol of cells. Endocytosis is a major pathway for the intracellular trafficking of sEVs, and some sEVs can fuse with late endosomes to release cargoes into the cytosol. Our understanding of the mechanisms regulating sEV composition heterogeneity and the molecular mechanism of the membrane fusion between sEVs and endosomes is limited. Here, we show that the core protein of the syndecan-4 ectodomain, the syndecan-4 ectodomain without heparan sulfate, on sEVs promoted this membrane fusion. In an in vitro lipid-mixing assay, the core protein of the syndecan-4 ectodomain was found to promote membrane fusion under the acidic conditions that are found in late endosomes. A recombinant core protein of the syndecan-4 ectodomain showed higher fusion activity than the domain with heparan sulfate. Conformational changes in the core protein were observed depending on the pH. The involvement of the core protein in membrane fusion was further investigated in a cell-based assay. Our results indicated that the conformation of the core protein was changed in late endosomes, which induced membrane fusion along with an increase in the membrane fluidity of the sEVs. This mechanism involving fusion proteins is similar to the mechanism of many virus infection systems. Syndecan-4, which is initially a glycoprotein containing heparan sulfate on the plasma membrane, has various functions, including cell adhesion and cell signaling, which are mainly thought to be facilitated through the heparan sulfate, and our results indicate the versatility of syndecan-4 actions in vivo.

Lipid nanoparticles (LNPs)-encapsulating mRNA (mRNA-LNPs) have become an important modality for vaccine development. mRNA-LNPs also have the ability to introduce therapeutic proteins, which suggests that they should also be a promising modality for gene therapy. However, the intrinsic adjuvant activity of mRNA-LNPs is a fundamental function of the LNPs in RNA vaccines, and this has shown a potential risk of inducing anti-transgene immunity when mRNA-LNPs were used in gene therapy. Therefore, a reduction in the adjuvant activity and adaptive immunity against an expressed protein are prerequisites for therapeutic applications. In this study, two strategies were combined to modulate the adjuvant activity of subcutaneously injected mRNA-LNPs: (1) loading a lipid derivative of dexamethasone to suppress inflammation and (2) inserting a sequence complementary to microRNA-142 into the mRNA to suppress gene expression in immune cells. The combination of these strategies reduced immune reactions against the model antigen ovalbumin in mRNA-LNPs.

Liver fibrosis, driven by unresolved inflammation and oxidative stress, lacks effective therapies. We developed hyaluronic acid (HA)-functionalized, pH-sensitive liposomes (HA-CeCPL) coencapsulating cryptotanshinone (CTS), an NLRP3 inflammasome inhibitor, and biomineralized ceria nanozymes (Ce-BSA) for synergistic liver fibrosis therapy. HA-CeCPL demonstrated pH-responsive payload release and preferential accumulation in fibrotic livers via CD44-mediated targeting of macrophages. In vitro, HA-CeCPL enhanced cellular uptake in macrophages, suppressed NLRP3 inflammasomes activation, and reduced IL-1β secretion. Meanwhile, the nanozyme-liposome complexs effectively scavenged reactive oxygen species (ROS), thus attenuating HSC activation, as evidenced by downregulation of α-smooth muscle actin. In vivo, HA-CeCPL exhibited superior hepatic targeting in CCl₄-induced fibrotic mice. It significantly ameliorated liver injury, restored liver function, reduced collagen deposition, and suppressed α-SMA expression. Furthermore, HA-CeCPL interfered with NLRP3 inflammasome signaling and pro-inflammatory cytokine cascades, breaking the inflammation-fibrosis cycle. These results demonstrate that the targeted dual-pathway strategy (simultaneously quenching ROS and blocking NLRP3 activation) synergistically resolves liver fibrosis, offering a promising nanotherapeutic approach.

Gastrin-releasing peptide receptor (GRPR) is overexpressed in glioma cells and can be specifically bound by Bombesin (BBN). Many molecular imaging agents based on the BBN structure have been tested in clinical trials and have shown promising results, but their in vivo stability needs to be improved. The aim of this study is to develop a novel d-amino acid-composed peptide BBN [as BBN(D)] and test its imaging performance by synthesizing two probes, i.e., BBN(D)-Cy5.5 and [⁶⁸Ga]Ga-DOTA-BBN(D), respectively, for near-infrared (NIR) fluorescence and PET/CT imaging. The HPLC purity of BBN(D)-Cy5.5 and DOTA-BBN(D) was >95%. And the mass spectrometry was used to confirm the identity of the product, LC-MS (ESI+) 528.5 was found [M+2H]/2. GRPR expression in U87-MG and glioma primary cells was confirmed by immunofluorescence. The in vitro. incubation of cells and BBN(D)-Cy5.5 exhibited a strong fluorescent signal and can be blocked by BBN. The in vivo subcutaneous and intracranial murine xenograft glioma models with two cell lines also demonstrated high specificity and tumor accumulation of BBN(D)-Cy5.5 and [⁶⁸Ga]Ga-DOTA-BBN(D) imaging tracers. PET/CT imaging with [⁶⁸Ga]Ga-DOTA-BBN(D) revealed optimal imaging at 40 min postinjection. Fluorescence imaging with BBN(D)-Cy5.5 was optimal at 4 h for subcutaneous models with tumor-to-background ratios peaked at 2.02 ± 0.136 and 2.00 ± 0.129 at 4 h. Biodistribution experiments confirmed that BBN(D) enhanced the accumulation of the probe in tumor tissue and endowed the probe with the ability to cross the blood-brain barrier; at 60 min postinjection of the probe through the teil vein, the uptake of [⁶⁸Ga]Ga-DOTA-BBN was less than 0.05%ID/g, while the uptake of [⁶⁸Ga]Ga-DOTA-BBN reached 0.70 ± 0.28%ID/g. The pathology and GRPR staining of ex vivo tissue from murine xenograft glioma models demonstrated strong consistency with fluorescence and PET/CT imaging. In conclusion, this study demonstrated that the d-amino acid–based BBN [BBN(D)] may provide specific imaging for glioma with high stability preoperatively and intraoperatively, warranting further exploration for clinical applications.

Poly(ADP-ribose) polymerase (PARP)-targeted positron emission tomography (PET) imaging has emerged as a valuable approach for identifying PARP inhibitor (PARPi) nonresponders, monitoring treatment response, and predicting prognosis. However, clinical translation of current tracers, such as [¹⁸F]FTT and [¹⁸F]PARPi, has been hampered by complex radiosynthesis and a high background signal. By leveraging the advantages of the photocatalyzed ¹⁸F-fluorination strategy and analyzing the interaction mode between Olaparib and PARP-1, we developed six novel PARP PET tracers. By finely tuning the physicochemical properties of these tracers with various electron-donating hydroxyl groups, effective direct ¹⁸F-deoxyfluorination, improved tumor uptake, and higher tumor-to-background ratios were achieved. All tracers were efficiently obtained with a high radiochemical purity. An in vitro experiment confirmed sufficient specific PARP binding of [¹⁸F]8a, [¹⁸F]8b, and [¹⁸F]8d, among which [¹⁸F]8a exhibited high tumor uptake (SUV_max = 0.22 ± 0.02) and superior tumor-to-muscle ratio (3.71 ± 0.18) at 1 h postinjection in U87MG tumor-bearing mice on PET/CT images, along with acceptable stability. Collectively, these findings highlight [¹⁸F]8a as a promising PARP PET tracer, combining improved synthetic accessibility with robust imaging performance, and underscore its potential for clinical translation.

The rapid development of mRNA vaccines during the COVID-19 pandemic has highlighted the critical role of lipid nanoparticles (LNPs) as delivery systems. The advantages of prefilled syringes (PFSs) in mRNA-LNP administration are widely recognized. The compatibility of mRNA-LNP drugs with tungsten in PFSs has not yet been investigated. In this study, we used polyadenylic acid (Poly A) as an mRNA model to conduct accelerated stability experiments under conditions of 4 °C, 25 °C, and light exposure, examining the effects of three tungsten sources (commercial salts or tungsten extracted from syringe pins) on the physicochemical properties of LNPs. Additionally, enhanced green fluorescent protein (eGFP)-mRNA and Poly A were compared to validate the changes in bioactivity. Our findings revealed that tungsten significantly increased the particle size and polydispersity index (PDI) of Poly A-LNPs, while reducing zeta potential and encapsulation efficiency. Transmission electron microscopy (TEM) further demonstrated that tungsten-induced structural damage to Poly A-LNPs. eGFP-LNPs spiked with 50 ppm tungsten extract completely lost activity after 6 weeks of storage at 25 °C, even though they exhibited greater physicochemical stability than Poly A-LNPs. Light exposure, while having no significant impact on physicochemical parameters, substantially diminished LNP bioactivity. Subsequent nucleic acid integrity testing of tungsten-spiked eGFP-mRNA revealed that tungsten caused minimal changes in physicochemical properties, such as particle size and PDI, under real-world conditions, but significantly compromised eGFP-mRNA integrity. This suggests that mRNA integrity, rather than physicochemical metrics such as particle size, PDI, or encapsulation efficiency, is the critical quality attribute determining mRNA-LNP bioactivity.