Surface modification of extracellular vesicles with polyoxazolines to enhance their plasma stability and tumor accumulation.

Extracellular vesicles (EVs) are future promising therapeutics, but their instability in vivo after administration remains an important barrier to their further development. Many groups evaluated EV surface modification strategies to add a targeting group with the aim of controlling EV biodistribution. Conversely, fewer groups focused on their stabilization to obtain "stealth" allogenic EVs. Modulating their stabilization and biodistribution is an essential prerequisite for their development as nano-therapeutics. Here, we explored polyoxazolines with lipid anchors association to the EV membrane (POxylation as an alternative to PEGylation) to stabilize EVs in plasma and control their biodistribution, while preserving their native properties. We found that this modification maintained and seemed to potentiate the immunomodulatory properties of EVs derived from mesenchymal stem/stromal cells (MSC). Using a radiolabeling protocol to track EVs at a therapeutically relevant concentration in vivo, we demonstrated that POxylation is a promising option to stabilize EVs in plasma because it increased EV half-life by 6 fold at 6 h post-injection. Moreover, EV accumulation in tumors was higher after POxylation than after PEGylation.

Engineered and hybrid human megakaryocytic extracellular vesicles for targeted non-viral cargo delivery to hematopoietic (blood) stem and progenitor cells.

Native and engineered extracellular vesicles generated from human megakaryocytes (huMkEVs) or from the human megakaryocytic cell line CHRF (CHEVs) interact with tropism delivering their cargo to both human and murine hematopoietic stem and progenitor cells (HSPCs). To develop non-viral delivery vectors to HSPCs based on MkEVs, we first confirmed, using NOD-scid IL2Rγnull (NSG™) mice, the targeting potential of the large EVs, enriched in microparticles (huMkMPs), chosen for their large cargo capacity. 24 h post intravenous infusion into NSG mice, huMkEVs induced a nearly 50% increase in murine platelet counts. PKH26-labeled huMkEVs or CHEVs localized to the HSPC-rich bone marrow preferentially interacting with murine HSPCs, thus confirming their receptor-mediated tropism for NSG HSPCs, and their potential to treat thromobocytopenias. We explored this tropism to functionally deliver synthetic cargo, notably plasmid DNA coding for a fluorescent reporter, to NSG HSPCs both in vitro and in vivo. We loaded huMkEVs with plasmid DNA either through electroporation or by generating hybrid particles with preloaded liposomes. Both methods facilitated successful functional targeted delivery of pDNA, as tissue weight-normalized fluorescence intensity of the expressed fluorescent reporter was significantly higher in bone marrow than other tissues. Furthermore, the fraction of fluorescent CD117+ HSPCs was nearly 19-fold higher than other cell types within the bone marrow 72-h following administration of the hybrid particles, further supporting that HSPC tropism is retained when using hybrid particles. These data demonstrate the potential of these EVs as a non-viral, HSPC-specific cargo vehicle for gene therapy applications to treat hematological diseases.

3D light-sheet fluorescence microscopy in preclinical and clinical drug discovery.

Light-sheet fluorescence microscopy (LSFM) combined with tissue clearing has emerged as a powerful technology in drug discovery. LSFM is applicable to a variety of samples, from rodent organs to clinical tissue biopsies, and has been used for characterizing drug targets in tissues, demonstrating the biodistribution of pharmaceuticals and determining their efficacy and mode of action. LSFM is scalable to high-throughput analysis and provides resolution down to the single cell level. In this review, we describe the advantages of implementing LSFM into the drug discovery pipeline and highlight recent advances in this field.

COVID-19 Vaccine mRNA Biodistribution: Maternal and Fetal Exposure Risks.

SARS-CoV-2 infection during pregnancy has severe consequences on maternal and neonatal health. Presently, vaccination stands as a critical preventive measure for mitigating infection-related risks. Although the initial clinical trials for the COVID-19 vaccines excluded pregnant women, subsequent investigations have indicated mRNA vaccinations' effectiveness and short-term safety during pregnancy. However, there is a lack of information regarding the potential biodistribution of the vaccine mRNA during pregnancy and lactation. Recent findings indicate that COVID-19 vaccine mRNA has been detected in breast milk, suggesting that its presence is not confined to the injection site and raises the possibility of similar distribution to the placenta and the fetus. Furthermore, the potential effects and responses of the placenta and fetus to the vaccine mRNA are still unknown. While potential risks might exist with the exposure of the placenta and fetus to the COVID-19 mRNA vaccine, the application of mRNA therapies for maternal and fetal conditions offers a groundbreaking prospect. Future research should leverage the unique opportunity provided by the first-ever application of mRNA vaccines in humans to understand their biodistribution and impact on the placenta and fetus in pregnant women. Such insights could substantially advance the development of safer and more effective future mRNA-based therapies during pregnancy.

Development and Validation of an LC-MS/MS Assay for the Quantitation of MO-OH-Nap Tropolone in Mouse Plasma: Application to In Vitro and In Vivo Pharmacokinetic Studies.

A rapid, selective, and sensitive liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantitation of MO-OH-Nap tropolone (MO-OH-Nap) in mouse plasma. MO-OH-Nap is an α-substituted tropolone with anti-proliferative properties in various cancer cell lines. Detection and separation of analytes was achieved on an ACE Excel C18 (1.7 µm, 100 × 2.1 mm, MAC-MOD Analytical, Chadds Ford, PA, USA) column with mobile phase consisting of 0.05% trifluoroacetic acid in water (mobile phase A) and 0.05% trifluoroacetic acid in acetonitrile (mobile phase B), with an isocratic elution of 15:85% (A:B) at a total flow rate of 0.25 mL/min. The LC-MS/MS system was operated at unit resolution in multiple reaction monitoring (MRM) mode, using precursor ion > product ion combination of 249.10 > 202.15 m/z for MO-OH-Nap and 305.10 > 215.05 m/z for the internal standard (IS), BA-SM-OM. The MS/MS response was linear over a concentration range of 1 to 500 ng/mL with a correlation coefficient (r2) of ≥0.987. The within- and between-batch precision (%RSD) and accuracy (%Bias) were within acceptable limits. The validated method was successfully applied to determine MO-OH-Nap metabolic stability, plasma protein binding, and bio-distribution studies of MO-OH-Nap in CD-1 mice.

Limb Perfusion Delivery of a rAAV1 Alpha-1 Antitrypsin Vector in Non-Human Primates Is Safe but Insufficient for Therapy.

BACKGROUND/OBJECTIVES: α-1 antitrypsin (AAT) deficiency is an inherited, genetic condition characterized by reduced serum levels of AAT and increased risk of developing emphysema and liver disease. AAT is normally synthesized primarily in the liver, but muscle-targeting with a recombinant adeno-associated virus (rAAV) vector for α-1 antitrypsin (AAT) gene therapy has been used to minimize liver exposure to the virus and hepatotoxicity. Clinical trials of direct intramuscular (IM) administration of rAAV1-hAAT have demonstrated its overall safety and transgene expression for 5 years. However, the failure to reach the therapeutic target level after 100 large-volume (1.5 mL) IM injections of maximally concentrated vector led us to pursue a muscle-targeting approach using isolated limb perfusion. This targets the rAAV to a greater muscle mass and allows for a higher total volume (and thereby a higher dose) than is tolerable by multiple direct IM injections. Limb perfusion has been shown to be feasible in non-human primates using the rAAV1 serotype and a ubiquitous promoter expressing an epitope-tagged AAT matched to the host species. METHODS: In this study, we performed a biodistribution and preclinical safety study in non-human primates with a clinical candidate rAAV1-human AAT (hAAT) vector at doses ranging from 3.0 × 1012 to 1.3 × 1013 vg/kg, bracketing those used in our clinical trials. RESULTS: We found that limb perfusion delivery of rAAV1-hAAT was safe and showed a biodistribution pattern similar to previous studies. However, serum levels of AAT obtained with high-dose limb perfusion still reached only ~50% of the target serum levels. CONCLUSIONS: Our results suggest that clinically effective AAT gene therapy may ultimately require delivery at doses between 3.5 × 1013-1 × 1014 vg/kg, which is within the dose range used for approved rAAV gene therapies. Muscle-targeting strategies could be incorporated when delivering systemic administration of high-dose rAAV gene therapies to increase transduction of muscle tissues and reduce the burden on the liver, especially in diseases that can present with hepatotoxicity such as AAT deficiency.

Ionic co-aggregates based intravenous drug delivery: Evaluation on kinetics and distribution of the drug payloads and nanocarriers.

Surfactants are crucial in formulating poorly soluble drugs but lead to serious side effects due to PEG chains. Novel supra-amphiphiles consisting of fatty acids and choline are developed, which spontaneously form ionic co-aggregates (ICAs) in water and exhibit strong solubilizing capacity. Paclitaxel (PTX) is adopted as a model drug here to evaluate the feasibility of choline oleate-based ICAs in the intravenous delivery of poorly soluble drugs by comparing the kinetics and distribution of payloads and nanocarriers. Choline oleate presents a maximum 10-fold enhancement in solubilizing capacity to PTX than Cremophor EL (CreEL), enabling a one-tenth use level in the formulation. Aggregation-caused quenching probes are utilized to evaluate the kinetics and biodistribution of ICAs or CreEL-based micelles (MCs). A huge gap is found between the pharmacokinetic and particokinetic curves of either nanocarrier, indicating fast leakage. ICAs lead to faster PTX leakage in blood circulation but higher PTX distribution to organs than MCs. MCs present a longer circulation in blood but a slower distribution to organs than ICAs. ICAs do not arise adverse reactions in rats following repeated injections, while MCs cause pathological changes in varying degrees. In conclusion, choline oleate-based ICAs provide an alternative to surfactants in formulating poorly soluble drugs.

Biodistribution and toxic potential of silver nanoparticles when introduced to the female rat reproductive tract.

The prevalence of ionic silver and silver nanomaterials in hygiene products has been increasing due to their antimicrobial activity. While numerous studies have examined the effects of nanosilver in laboratory settings, there is a limited understanding of its impact on reproductive tissues, as well as its biodistribution and toxicity upon intra-vaginal exposure. If ionic or nanosilver enters adjacent and internal tissues via intra-vaginal exposure, the overuse of hygiene products containing silver may potentially threaten woman's health. This study investigated the effects of intra-vaginal silver exposure in Female Fischer 344 rats to single and multiple doses of a commercial product containing silver, along with standard nanosilver materials. Custom tampons were developed to simulate practical usage scenarios. The analysis of tissue biodistribution revealed that epithelial penetration and redistribution of silver was observed with most administered silver eliminated in feces (8-44 %), and secondary tissues containing 1-18 % of the dose, predominantly localized in the reproductive tract. In a subsequent toxicity study, vaginal histopathology indicated a cellular inflammatory reaction (neutrophil infiltration) associated with the presence of foreign silver material upon a single administration. Interestingly, no noticeable difference in histopathology incidence was observed upon multiple exposures to silver compared to the control group. Clinical chemistry and hematology analyses following acute exposure to silver nanomaterials showed no significant abnormalities. Overall, acute vaginal exposure to silver nanomaterials and ionic silver resulted in limited silver persistence, local tissue reactivity, epithelial penetration of silver resulting in accumulation in distant organs, and elimination primarily through feces. In vitro data suggested potential alterations in normal vaginal flora. Long-term studies are still lacking in this area.

The Bifunctional Dimer Caffeine-Indan Attenuates α-Synuclein Misfolding, Neurodegeneration and Behavioral Deficits after Chronic Stimulation of Adenosine A1 Receptors.

We previously found that chronic adenosine A1 receptor stimulation with N6-Cyclopentyladenosine increased α-synuclein misfolding and neurodegeneration in a novel α-synucleinopathy model, a hallmark of Parkinson's disease. Here, we aimed to synthesize a dimer caffeine-indan linked by a 6-carbon chain to cross the blood-brain barrier and tested its ability to bind α-synuclein, reducing misfolding, behavioral abnormalities, and neurodegeneration in our rodent model. Behavioral tests and histological stains assessed neuroprotective effects of the dimer compound. A rapid synthesis of the 18F-labeled analogue enabled Positron Emission Tomography and Computed Tomography imaging for biodistribution measurement. Molecular docking analysis showed that the dimer binds to α-synuclein N- and C-termini and the non-amyloid-ß-component (NAC) domain, similar to 1-aminoindan, and this binding promotes a neuroprotective α-synuclein "loop" conformation. The dimer also binds to the orthosteric binding site for adenosine within the adenosine A1 receptor. Immunohistochemistry and confocal imaging showed the dimer abolished α-synuclein upregulation and aggregation in the substantia nigra and hippocampus, and the dimer mitigated cognitive deficits, anxiety, despair, and motor abnormalities. The 18F-labeled dimer remained stable post-injection and distributed in various organs, notably in the brain, suggesting its potential as a Positron Emission Tomography tracer for α-synuclein and adenosine A1 receptor in Parkinson's disease therapy.

Maternal stress during pregnancy alters circulating small extracellular vesicles and enhances their targeting to the placenta and fetus.

BACKGROUND: Maternal psychological distress during pregnancy can negatively impact fetal development, resulting in long-lasting consequences for the offspring. These effects show a sex bias. The mechanisms whereby prenatal stress induces functional and/or structural changes in the placental-fetal unit remain poorly understood. Maternal circulating small extracellular vesicles (sEVs) are good candidates to act as "stress signals" in mother-to-fetus communication. Using a repetitive restraint-based rat model of prenatal stress, we examined circulating maternal sEVs under stress conditions and tested whether they could target placental-fetal tissues. RESULTS: Our mild chronic maternal stress during pregnancy paradigm induced anhedonic-like behavior in pregnant dams and led to intrauterine growth restriction (IUGR), particularly in male fetuses and placentas. The concentration and cargo of maternal circulating sEVs changed under stress conditions. Specifically, there was a significant reduction in neuron-enriched proteins and a significant increase in astrocyte-enriched proteins in blood-borne sEVs from stressed dams. To study the effect of repetitive restraint stress on the biodistribution of maternal circulating sEVs in the fetoplacental unit, sEVs from pregnant dams exposed to stress or control protocol were labeled with DiR fluorescent die and injected into pregnant females previously exposed to control or stress protocol. Remarkably, maternal circulating sEVs target placental/fetal tissues and, under stress conditions, fetal tissues are more receptive to sEVs. CONCLUSION: Our results suggest that maternal circulating sEVs can act as novel mediators/modulators of mother-to-fetus stress communication. Further studies are needed to identify placental/fetal cellular targets of maternal sEVs and characterize their contribution to stress-induced sex-specific placental and fetal changes.

Validation of ZIP4 as a tumour-associated antigen for nanotargeting.

Pancreatic ductal adenocarcinoma remains a highly aggressive and untreatable cancer. There is a need to develop a new PDAC-associated antigen-targeting drug delivery system to tackle this disease. We validated choosing ZIP4 as a putative target in PDAC theranostics. We developed a nanosystem composed of a fluorescent polystyrene core coated with gold nanoparticles onto which a ZIP4-specific polyclonal antibody is attached. The polystyrene core's fluorescence properties allow the nanosystem tracking by intravital imaging. We also developed two ZIP4-expressing cell lines by stably transfecting HEK293 and RWP1 cells with a ZIP4-coding plasmid that simultaneously provides cells with puromycin resistance. We studied the cell internalisation of the as-synthesised nanoparticles and demonstrated that ZIP4-expressing HEK293 and ZIP4-expressing RWP1 cells tended to take up more ZIP4-targeting nanoparticles. Moreover, we observed that ZIP4-targeting nanoparticles accumulated more in ZIP4-expressing HEK293 and RWP1 tumours when injected intravenously in a subcutaneous xenograft and an orthotopic in vivo model, respectively. Furthermore, the administration of these nanoparticles did not induce any significant systemic toxicity as determined by histological analysis of all organs. Altogether, these results provide the first evidence of the feasibility of using a ZIP4-targeting nanosystem further to design efficient therapeutic and diagnostic tools for PDAC.

Approbation of a Homologous Model of the Antitumor Vaccine Based on Mature Mouse Dendritic Cells to Study the Biodistribution of the Cell Product.

Homologous animal cell product was obtained in protocol developed for female BALB/c mice. Dendritic cell (DC) migration from the injection site into the draining lymph nodes was evaluated. The number of DC labeled with carboxyfluorescein succinimidyl ester (CFSE) in draining lymph nodes increased from 5.3% (16 h) to 13.3% (48 h) (p=0.028) with a maximum at 72 h (15.4%, p=0.003). The immunophenotype of CFSE-DC detected in murine lymph nodes corresponded to the immunophenotype of mature vaccine DCs: they expressed differentiation markers CD11c, CD80, CD83, and CD86 (p>0.05 vs initial DC).

Study on Preclinical Safety and Toxic Mechanism of Human Umbilical Cord Mesenchymal Stem Cells in F344RG Rats.

Mesenchymal stem cells have made remarkable progress in recent years. Many studies have reported that human umbilical cord mesenchymal stem cells (hUC-MSCs) have no toxicity, but thromboembolism appeared in patients treated with hUC-MSCs. Therefore, people are still worried about the safety of clinical application. The study aims to determine the safety, potential toxic mechanism and biodistribution of hUC-MSCs. F344RG rats were given 5 or 50 million cells/kg of hUC-MSCs by single administration in compliance with Good Laboratory Practice standards. Standard toxicity was performed. RNA sequencing was then performed to explore the potential toxic mechanisms. In parallel, the biodistribution of hUC-MSCs was examined. The dose of 5 million cells/kg hUC-MSCs had no obvious toxicity on symptom, weight, food intake, hematology, serum biochemistry, urine biochemistry, cytokines, and histopathology. However, blood-tinged secretions in the urethral orifice and 20% mortality occurred at 50 million cells/kg. Disseminated intravascular coagulopathy (DIC) is the leading cause of death. hUC-MSCs significantly upregulated complement and coagulation cascade pathways gene expression, resulting in DIC. Besides, hUC-MSCs upregulated fibrinolytic system suppressor genes A2m, Serping1 and Serpinf2. hUC-MSCs survived in rats for less than 28 days, no hUC-MSC was detected in tissues outside the lungs. There was no toxicity in F344RG rats at 5 million cells/kg, but some toxicities were detected at 50 million cells/kg. hUC-MSCs significantly upregulated complement and coagulation cascade pathways, upregulated the expression of fibrinolytic system suppressor genes A2m, Serping1 and Serpinf2, to inhibit fibrinolytic system, caused DIC, which provided a new insight into the toxic mechanism of hUC-MSCs.

A novel approach to quantitate biodistribution and transduction of adeno-associated virus gene therapy using radiolabeled AAV vectors in mice.

An understanding of recombinant adeno-associated virus (AAV) biodistribution profiles is an important element of a preclinical development program. Here, we have developed a radiolabeling strategy utilizing the co-delivery of 125I (non-residualizing) and 111In (residualizing) radionuclide-conjugated AAVs to provide a detailed distribution quantification at tissue level delineating between the cellular internalized AAV (degraded, 111In-125I) and AAV remaining in the extracellular matrix (intact, 125I). This labeling method has been successfully applied to AAV9 and AAV-PHP.eB as tool molecules without altering the physical properties and biological activities of the AAVs. Upon labeling with either of the radioactive probes, these molecules were systemically injected into C57BL/6 mice. The biodistribution results indicate that AAVs, with a fast distribution profile, were mainly located in the extracellular matrix of highly perfused organs such as liver and spleen at early time points, leading to a difference between capsid quantification and vector genome quantification. The results suggest that the 125I-AAV/111In-AAV co-delivery approach offers a robust and efficient analytical strategy to investigate the detailed tissue distribution of AAV vectors, including both vector genome and protein capsids. This novel method has the potential to be applied to capsid optimization, selection, and lead candidate development.

Safe and effective in vivo delivery of DNA and RNA using proteolipid vehicles.

Genetic medicines show promise for treating various diseases, yet clinical success has been limited by tolerability, scalability, and immunogenicity issues of current delivery platforms. To overcome these, we developed a proteolipid vehicle (PLV) by combining features from viral and non-viral approaches. PLVs incorporate fusion-associated small transmembrane (FAST) proteins isolated from fusogenic orthoreoviruses into a well-tolerated lipid formulation, using scalable microfluidic mixing. Screening a FAST protein library, we identified a chimeric FAST protein with enhanced membrane fusion activity that improved gene expression from an optimized lipid formulation. Systemically administered FAST-PLVs showed broad biodistribution and effective mRNA and DNA delivery in mouse and non-human primate models. FAST-PLVs show low immunogenicity and maintain activity upon repeat dosing. Systemic administration of follistatin DNA gene therapy with FAST-PLVs raised circulating follistatin levels and significantly increased muscle mass and grip strength. These results demonstrate the promising potential of FAST-PLVs for redosable gene therapies and genetic medicines.

Exploring nalbuphine loaded chitosan nanoparticles for effective pain management through intranasal administration: a comparative study.

BACKGROUND: Intranasal drug delivery shows potential for brain access via olfactory and trigeminal routes. PURPOSE: This work aimed to ensure brain availability of nalbuphine via the nasal route. METHOD: Chitosan based nanoparticles loaded with nalbuphine were successfully prepared using ionic gelation method and characterised. RESULT: SEM results revealed that the nanoparticles were spherical in shape, with an average size of 192.4 ± 11.6 nm. Zeta potential and entrapment efficiency was found 32.8 mV and 88.43 ± 7.75%, respectively. The X-ray diffractometry and DSC results unravel a profound understanding on the physical and thermal characteristics. The in-vitro release of nalbuphine from the nanoparticles was biphasic, with an initial burst release followed by a slow-release profile. In-vitro cell study on HEK-293 cells and microscopic images of brain tissue confirmed the safety profile of formulation. In-vivo efficacy studies on animal confirmed the effectiveness of developed intranasal formulation as compared to the standard therapy. The in-vivo pharmacokinetic studies showed that the prepared nanoparticles were able to efficiently deliver nalbuphine to the brain in comparison to the other body organs. Gamma scintigraphy images showed retention of the drug in the brain. Furthermore, the efficacy studies confirmed that the nanoparticles were found significantly more effective than the marketed formulation in pain management.

Liposome-encapsulated aprotinin biodistribution in mice: Side-by-side comparison with free drug formulation.

Injuries of the respiratory system caused by viral infections (e.g., by influenza virus, respiratory syncytial virus, metapneumovirus, or coronavirus) can lead to long-term complications or even life-threatening conditions. The challenges of treatment of such diseases have become particularly pronounced during the recent pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). One promising drug is the anti-fibrinolytic and anti-inflammatory protease inhibitor aprotinin, which has demonstrated considerable inhibition of the replication of some viruses. Encapsulation of aprotinin in liposomes can significantly improve the effectiveness of the drug, however, the use of nanoparticles as carriers of aprotinin can radically change its biodistribution in the body. Here we show that the liposomal form of aprotinin accumulates more efficiently in the lungs, heart, and kidneys than the molecular form by side-by-side comparison of the ex vivo biodistribution of these two fluorescently labeled formulations in mice using bioimaging. In particular, we synthesized liposomes of different compositions and studied their accumulation in various organs and tissues. Direct comparison of the biodistributions of liposomal and free aprotinin showed that liposomes accumulated in the lungs 1.82 times more effectively, and in the heart and kidneys - 3.56 and 2.00 times, respectively. This suggests that the liposomal formulation exhibits a longer residence time in the target organ and, thus, has the potential for a longer therapeutic effect. The results reveal the great potential of the aprotinin-loaded liposomes for the treatment of respiratory system injuries and heart- and kidney-related complications of viral infections.

Doxorubicin-Loaded Ultrasmall Gold Nanoparticles (1.5 nm) for Brain Tumor Therapy and Assessment of Their Biodistribution.

Ultrasmall gold nanoparticles (1.5 nm) were covalently conjugated with doxorubicin (AuDox) and AlexaFluor647 (AuAF647) to assess their biodistribution and their efficiency toward brain tumors (glioblastoma). A thorough characterization by transmission electron microscopy, small-angle X-ray scattering, and differential centrifugal sedimentation confirmed their uniform ultrasmall nature which makes them very mobile in the body. Each nanoparticle carried either 13 doxorubicin molecules (AuDox) or 2.7 AlexaFluor-647 molecules (AuAF647). The firm attachment of the ligands to the nanoparticles was demonstrated by their resilience to extensive washing, followed by centrifugation. The particles easily entered mammalian cells (HeLa, T98-G, brain endothelial cells, and human astrocytes) due to their small size. The intravenously delivered fluorescing AuAF647 nanoparticles crossed the blood-brain barrier with ∼23% accumulation in the brain tumor in an orthotopic U87 brain tumor model in nude mice. This was confirmed by elemental analysis (gold; inductively coupled plasma optical emission spectroscopy) in various organs. The doxorubicin-loaded AuDox nanoparticles inhibited brain tumor growth and prolonged animal survival without adverse side effects. Most of the nanoparticles (84%) had been excreted from the animal after 24 h, indicating a high mobility in the body.

Nicardipine-chitosan nanoparticles alleviate thioacetamide-induced acute liver injury by targeting NFκB/NLRP3/IL-1ß signaling in rats: Unraveling new roles beyond calcium channel blocking.

Liver inflammatory diseases are marked by serious complications. Notably, nicardipine (NCD) has demonstrated anti-inflammatory properties, but its benefits in liver inflammation have not been studied yet. However, the therapeutic efficacy of NCD is limited by its short half-life and low bioavailability. Therefore, we aimed to evaluate the potential of NCD-loaded chitosan nanoparticles (ChNPs) to improve its pharmacokinetic profile and hepatic accumulation. Four formulations of NCD-ChNPs were synthesized and characterized. The optimal formulation (NP2) exhibited a mean particle diameter of 172.6 ± 1.94 nm, a surface charge of +25.66 ± 0.93 mV, and an encapsulation efficiency of 88.86 ± 1.17 %. NP2 showed good physical stability as a lyophilized powder over three months. It displayed pH-sensitive release characteristics, releasing 77.15 ± 5.09 % of NCD at pH 6 (mimicking the inflammatory microenvironment) and 52.15 ± 3.65 % at pH 7.4, indicating targeted release in inflamed liver tissues. Pharmacokinetic and biodistribution studies revealed that NCD-ChNPs significantly prolonged NCD circulation time and enhanced its concentration in liver tissues compared to plain NCD. Additionally, the study investigated the protective effects of NCD-ChNPs in thioacetamide-induced liver injury in rats by modulating the NFκB/NLRP3/IL-1ß signaling axis. NCD-ChNPs effectively inhibited NFκB activation, reduced NLRP3 inflammasome activation, and subsequent release of IL-1ß, which correlated with improved hepatic function and reduced inflammation and oxidative stress. These findings highlight the potential of NCD-ChNPs as a promising nanomedicine strategy for the treatment of liver inflammatory diseases, warranting further investigation into their clinical applications, particularly in hypertensive patients with liver inflammatory conditions.

Delivery vehicle and route of administration influences self-amplifying RNA biodistribution, expression kinetics, and reactogenicity.

Self-amplifying RNA (saRNA) is a next-generation RNA platform derived from an alphavirus that enables replication in host cytosol, offering a promising shift from traditional messenger RNA (mRNA) therapies by enabling sustained protein production from minimal dosages. The approval of saRNA-based vaccines, such as the ARCT-154 for COVID-19 in Japan, underscores its potential for diverse therapeutic applications, including vaccine development, cancer immunotherapy, and gene therapy. This study investigates the role of delivery vehicle and administration route on saRNA expression kinetics and reactogenicity. Employing ionizable lipid-based nanoparticles (LNPs) and polymeric nanoparticles, we administered saRNA encoding firefly luciferase to BALB/c mice through six routes (intramuscular (IM), intradermal (ID), intraperitoneal (IP), intranasal (IN), intravenous (IV), and subcutaneous (SC)), and observed persistent saRNA expression over a month. Our findings reveal that while LNPs enable broad route applicability and stability, pABOL (poly (cystamine bisacrylamide-co-4-amino-1-butanol)) formulations significantly amplify protein expression via intramuscular delivery. Notably, the disparity between RNA biodistribution and protein expression highlight the nuanced interplay between administration routes, delivery vehicles, and therapeutic outcomes. Additionally, our research unveiled distinct biodistribution profiles and inflammatory responses contingent upon the chosen delivery formulation and route. This research illuminates the intricate dynamics governing saRNA delivery, biodistribution and reactogenicity, offering essential insights for optimizing therapeutic strategies and advancing the clinical and commercial viability of saRNA technologies.