Overcoming Solubility Challenges: Liposomal isoCoQ-Carbazole as a Promising Anti-Tumor Agent for Inoperable and Radiation-Insensitive cancers.

This study evaluated the potential of isoCoQ-Carbazole, a diheterocyclic analog of isoCA-4, as an anti-tumor agent. To overcome its low aqueous solubility, liposomes were developed as a delivery system for the compound. In vitro experiments showed that loaded liposomes exhibited similar activity to the free form on multiple human tumor cell lines. In vivo experiments using a palliative intratumoral injection chemotherapy approach further demonstrated that isoCoQ-Carbazole loaded liposomes significantly reduced tumor growth in a CA-4-resistant HT29 cell model, without inducing any observable toxicity or weight loss in the treated mice. These findings suggest that liposomal isoCoQ-Carbazole may hold promise as a potential therapeutic agent for the treatment of inoperable, radiation-insensitive cancers.

Liposomal AntagomiR-155-5p Restores Anti-Inflammatory Macrophages and Improves Arthritis in Preclinical Models of Rheumatoid Arthritis.

OBJECTIVE: We previously reported an increased expression of microRNA-155 (miR-155) in the blood monocytes of patients with rheumatoid arthritis (RA) that could be responsible for impaired monocyte polarization to anti-inflammatory M2-like macrophages. In this study, we employed two preclinical models of RA, collagen-induced arthritis and K/BxN serum transfer arthritis, to examine the therapeutic potential of antagomiR-155-5p entrapped within PEGylated (polyethylene glycol [PEG]) liposomes in resolution of arthritis and repolarization of monocytes towards the anti-inflammatory M2 phenotype. METHODS: AntagomiR-155-5p or antagomiR-control were encapsulated in PEG liposomes of 100 nm in size and -10 mV in zeta potential with high antagomiR loading efficiency (above 80%). Mice were injected intravenously with 1.5 nmol/100 µL PEG liposomes containing antagomiR-155-5p or control after the induction of arthritis. RESULTS: We demonstrated the biodistribution of fluorescently tagged PEG liposomes to inflamed joints one hour after the injection of fluorescently tagged PEG liposomes, as well as the liver's subsequent accumulation after 48 hours, indicative of hepatic clearance, in mice with arthritis. The injection of PEG liposomes containing antagomiR-155-5p decreased arthritis score and paw swelling compared with PEG liposomes containing antagomiR-control or the systemic delivery of free antagomiR-155-5p. Moreover, treatment with PEG liposomes containing antagomiR-155-5p led to the restoration of bone marrow monocyte defects in anti-inflammatory macrophage differentiation without any significant functional change in other immune cells, including splenic B and T cells. CONCLUSION: The injection of antagomiR-155-5p encapsulated in PEG liposomes allows the delivery of small RNA to monocytes and macrophages and reduces joint inflammation in murine models of RA, providing a promising strategy in human disease.

Assessment of Squalene-Adenosine Nanoparticles in Two Rodent Models of Cardiac Ischemia-Reperfusion.

Reperfusion injuries after a period of cardiac ischemia are known to lead to pathological modifications or even death. Among the different therapeutic options proposed, adenosine, a small molecule with platelet anti-aggregate and anti-inflammatory properties, has shown encouraging results in clinical trials. However, its clinical use is severely limited because of its very short half-life in the bloodstream. To overcome this limitation, we have proposed a strategy to encapsulate adenosine in squalene-based nanoparticles (NPs), a biocompatible and biodegradable lipid. Thus, the aim of this study was to assess, whether squalene-based nanoparticles loaded with adenosine (SQAd NPs) were cardioprotective in a preclinical cardiac ischemia/reperfusion model. Obtained SQAd NPs were characterized in depth and further evaluated in vitro. The NPs were formulated with a size of about 90 nm and remained stable up to 14 days at both 4 °C and room temperature. Moreover, these NPs did not show any signs of toxicity, neither on HL-1, H9c2 cardiac cell lines, nor on human PBMC and, further retained their inhibitory platelet aggregation properties. In a mouse model with experimental cardiac ischemia-reperfusion, treatment with SQAd NPs showed a reduction of the area at risk, as well as of the infarct area, although not statistically significant. However, we noted a significant reduction of apoptotic cells on cardiac tissue from animals treated with the NPs. Further studies would be interesting to understand how and through which mechanisms these nanoparticles act on cardiac cells.

Hyaluronic acid-conjugated liposomes loaded with dexamethasone: A promising approach for the treatment of inflammatory diseases.

Dexamethasone is a well-known anti-inflammatory drug readily used to treat many lung diseases. However, its side effects and poor lower airway deposition and retention are significant limitations to its usage. In this work, we developed lipid nanoparticulate platforms loaded with dexamethasone and evaluated their behavior in inflammatory lung models in vitro and in vivo. Dexamethasone-loaded liposomes with an average diameter below 150 nm were obtained using a solvent injection method. Three different formulations were produced with a distinct surface coating (polyethylene glycol, hyaluronic acid, or a mixture of both) as innovative strategies to cross the pulmonary mucus layer and/or target CD44 expressed on alveolar proinflammatory macrophages. Interestingly, while electron paramagnetic spectroscopy showed that surface modifications did not induce any molecular changes in the liposomal membrane, drug loading analysis revealed that adding the hyaluronic acid in the bilayer led to a decrease of dexamethasone loading (from 3.0 to 1.7 w/w%). In vitro experiments on LPS-activated macrophages demonstrated that the encapsulation of dexamethasone in liposomes, particularly in HA-bearing ones, improved its anti-inflammatory efficacy compared to the free drug. Subsequently, in vivo data revealed that while intratracheal administration of free dexamethasone led to an important inter-animals variation of efficacy, dexamethasone-loaded liposomes showed an improved consistency within the results. Our data indicate that encapsulating dexamethasone into lipid nanoparticles is a potent strategy to improve its efficacy after lung delivery.

Hyaluronan nanoplatelets exert an intrinsic anti-inflammatory activity in a rat model of bladder painful syndrome/interstitial cystitis.

Glycosaminoglycan (GAG) replenishment therapy consists of the instillation of GAG solutions directly in the bladder to alleviate Bladder Painful Syndrome/Interstitial Cystitis (BPS/IC). However, several issues were reported with this strategy because the GAG solutions are rapidly eliminated from the bladder by spontaneous voiding, and GAG have low bioadhesive behaviors. Herein, GAG nanomaterials with typical flattened morphology were obtained by a self-assembly process. The formation mechanism of those nanomaterials, denoted as nanoplatelets, involves the interaction of α-cyclodextrin cavity and alkyl chains covalently grafted on the GAG. Three GAG were used in this investigation, hyaluronan (HA), chondroitin sulfate (CS), and heparin (HEP). HA NP showed the best anti-inflammatory activity in an LPS-induced in vitro inflammation model of macrophages. They also exhibited the best therapeutic efficacy in a BPS/IC rat inflammation model. Histological examinations of the bladders revealed that HA NP significantly reduced bladder inflammation and regenerated the bladder mucosa. This investigation could open new perspectives to alleviate BPS/IC through GAG replenishment therapy.

Amphiphilic Phosphorus Dendrons Associated with Anti-inflammatory siRNA Reduce Symptoms in Murine Collagen-Induced Arthritis.

Small interfering RNA (siRNA) holds promise for treating rheumatoid arthritis by inhibiting major cytokines such as tumor necrosis factor-α (TNF-α). We developed original cationic amphiphilic phosphorus dendrons to produce dendriplexes associated with TNF-α siRNA. The dendrons were made of 10 pyrrolidinium end groups and a C17 aliphatic chain. The dendriplexes demonstrated the ability to protect siRNA from nuclease degradation and to promote macrophage uptake. Moreover, they led to potent inhibition of TNF-α expression in the lipopolysaccharide-activated mouse macrophage cell line RAW264.7 in vitro model. A significant anti-inflammatory effect in the murine collagen-induced arthritis model was observed through arthritis scoring and histological observations. These results open up essential perspectives in using this original amphiphilic dendron to reduce the disease burden and improve outcomes in chronic inflammatory diseases.

A Polymer Prodrug Strategy to Switch from Intravenous to Subcutaneous Cancer Therapy for Irritant/Vesicant Drugs.

Chemotherapy is almost exclusively administered via the intravenous (IV) route, which has serious limitations (e.g., patient discomfort, long hospital stays, need for trained staff, high cost, catheter failures, infections). Therefore, the development of effective and less costly chemotherapy that is more comfortable for the patient would revolutionize cancer therapy. While subcutaneous (SC) administration has the potential to meet these criteria, it is extremely restrictive as it cannot be applied to most anticancer drugs, such as irritant or vesicant ones, for local toxicity reasons. Herein, we report a facile, general, and scalable approach for the SC administration of anticancer drugs through the design of well-defined hydrophilic polymer prodrugs. This was applied to the anticancer drug paclitaxel (Ptx) as a worst-case scenario due to its high hydrophobicity and vesicant properties (two factors promoting necrosis at the injection site). After a preliminary screening of well-established polymers used in nanomedicine, polyacrylamide (PAAm) was chosen as a hydrophilic polymer owing to its greater physicochemical, pharmacokinetic, and tumor accumulation properties. A small library of Ptx-based polymer prodrugs was designed by adjusting the nature of the linker (ester, diglycolate, and carbonate) and then evaluated in terms of rheological/viscosity properties in aqueous solutions, drug release kinetics in PBS and in murine plasma, cytotoxicity on two different cancer cell lines, acute local and systemic toxicity, pharmacokinetics and biodistribution, and finally their anticancer efficacy. We demonstrated that Ptx-PAAm polymer prodrugs could be safely injected subcutaneously without inducing local toxicity while outperforming Taxol, the commercial formulation of Ptx, thus opening the door to the safe transposition from IV to SC chemotherapy.

Transtympanic injection of a liposomal gel loaded with N-acetyl-L-cysteine: A relevant strategy to prevent damage induced by cochlear implantation in guinea pigs?

Patients with residual hearing can benefit from cochlear implantation. However, insertion can damage cochlear structures and generate oxidative stress harmful to auditory cells. The antioxidant N-acetyl-L-cysteine (NAC) is a precursor of glutathione (GSH), a powerful endogenous antioxidant. NAC local delivery to the inner ear appeared promising to prevent damage after cochlear implantation in animals. NAC-loaded liposomal gel was specifically designed for transtympanic injection, performed both 3 days before and on the day of surgery. Hearing thresholds were recorded over 30 days in implanted guinea pigs with and without NAC. NAC, GSH, and their degradation products, N,N'-diacetyl-L-cystine (DiNAC) and oxidized glutathione (GSSG) were simultaneously quantified in the perilymph over 15 days in non-implanted guinea pigs. For the first time, endogenous concentrations of GSH and GSSG were determined in the perilymph. Although NAC-loaded liposomal gel sustained NAC release in the perilymph over 15 days, it induced hearing loss in both implanted and non-implanted groups with no perilymphatic GSH increase. Under physiological conditions, NAC appeared poorly stable within liposomes. As DiNAC was quantified at concentrations which were twice as high as NAC in the perilymph, it was hypothesized that DiNAC could be responsible for the adverse effects on hearing.

Squalene-based multidrug nanoparticles for improved mitigation of uncontrolled inflammation in rodents.

Uncontrolled inflammatory processes are at the root of numerous pathologies. Most recently, studies on confirmed COVID-19 cases have suggested that mortality might be due to virally induced hyperinflammation. Uncontrolled pro-inflammatory states are often driven by continuous positive feedback loops between pro-inflammatory signaling and oxidative stress, which cannot be resolved in a targeted manner. Here, we report on the development of multidrug nanoparticles for the mitigation of uncontrolled inflammation. The nanoparticles are made by conjugating squalene, a natural lipid, to adenosine, an endogenous immunomodulator, and then encapsulating α-tocopherol, as antioxidant. This resulted in high drug loading, biocompatible, multidrug nanoparticles. By exploiting the endothelial dysfunction at sites of acute inflammation, these multidrug nanoparticles delivered the therapeutic agents in a targeted manner, conferring survival advantage to treated animals in models of endotoxemia. Selectively delivering adenosine and antioxidants together could serve as a novel therapeutic approach for safe treatment of acute paradoxal inflammation.