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This review gathers recent studies, patents, and clinical trials involving the nasal administration of peptide drugs to supply a panorama of developing nanomedicine advances in this field. Peptide drugs have been featured in the pharmaceutical market, due to their high efficacy, biological activity, and low immunogenicity. Pharmaceutical industries need technology to circumvent issues relating to peptide stability and bioavailability. The oral route offers very harsh and unfavourable conditions for peptide administration, while the parenteral route is inconvenient and risky for patients. Nasal administration is an attractive alternative, mainly when associated with nanotechnological approaches. Nanomedicines may improve the nasal administration of peptide drugs by providing protection for the macromolecules from enzymes while also increasing their time of retention and permeability in the nasal mucosa. Nanomedicines for nasal administration containing peptide drugs have been acclaimed for both prevention, and treatment, of infections, including the pandemic COVID-19, cancers, metabolic and neurodegenerative diseases.

The low levels of toxicity and cytoprotective effect attributed to Achyrocline satureioides (Lam.) DC, a medicinal plant native to South America, are of interest for bovine mastitis therapy. This research paper reports the hypothesis that a nanoemulsion of macela extract (Achyrocline satureioides) exerts protective effects on bovine mammary alveolar cells -T (MAC-T) and increases the permeation of flavonoid compounds through mammary epithelium. Extract-loaded nanoemulsions (2.5 mg/ml) (NE-ML) (n = 4) were prepared using high-pressure homogenization with varying concentrations of flaxseed oil and Tween 80. Permeation and retention of free and nanoencapsulated quercetin, 3-O-methylquercetin and luteolin were performed on mammary glandular epithelium using Franz diffusion cells. The cell viability was evaluated on mammary epithelial cells (MAC-T lineage) using the MTT method (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) after exposure to loaded and blank nanoemulsions (NE-ML and NE-BL). Necrotic or apoptotic cell death was evaluated by flow cytometry after exposure to nanoemulsions (NE-ML and NE-BL). Subsequently, the cell death was assessed by previously treating MAC-T cells with NE-ML for 23 h, followed by exposure to H2O2 (2 mM) for 1 h. Higher permeation of quercetin and 3-O-methylquercetin in NE-ML was found compared to that of free extract with a final permeated amount of 50.7 ± 3.2 and 111.2 ± 0.6 μg/cm2 compared to 35.0 ± 0.6 and 48.9 ± 1.2, respectively. For NE-BL, the IC50 was at least 1.3% (v/v), while for the NE-ML, it was at least 2.6% (v/v). After exposure to NE-ML (5 and 1.2%, v/v), the percentage of apoptotic cells was reduced (±30%). For the H2O2 assay, the percentage of cells in necrosis was reduced by 40% after exposure to NE-ML1% (v/v) + H2O2 2 mM. The protective effects and increased permeation of macela nanoemulsion make this a promising new candidate for bovine mastitis therapy.

The low levels of toxicity and cytoprotective effect attributed to Achyrocline satureioides (Lam.) DC, a medicinal plant native to South America, are of interest for bovine mastitis therapy. This research paper reports the hypothesis that a nanoemulsion of macela extract (Achyrocline satureioides) exerts protective effects on bovine mammary alveolar cells -T (MAC-T) and increases the permeation of flavonoid compounds through mammary epithelium. Extract-loaded nanoemulsions (2.5 mg/ml) (NE-ML) (n = 4) were prepared using high-pressure homogenization with varying concentrations of flaxseed oil and Tween 80. Permeation and retention of free and nanoencapsulated quercetin, 3-O-methylquercetin and luteolin were performed on mammary glandular epithelium using Franz diffusion cells. The cell viability was evaluated on mammary epithelial cells (MAC-T lineage) using the MTT method (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) after exposure to loaded and blank nanoemulsions (NE-ML and NE-BL). Necrotic or apoptotic cell death was evaluated by flow cytometry after exposure to nanoemulsions (NE-ML and NE-BL). Subsequently, the cell death was assessed by previously treating MAC-T cells with NE-ML for 23 h, followed by exposure to H2O2 (2 mM) for 1 h. Higher permeation of quercetin and 3-O-methylquercetin in NE-ML was found compared to that of free extract with a final permeated amount of 50.7 ± 3.2 and 111.2 ± 0.6 μg/cm2 compared to 35.0 ± 0.6 and 48.9 ± 1.2, respectively. For NE-BL, the IC50 was at least 1.3% (v/v), while for the NE-ML, it was at least 2.6% (v/v). After exposure to NE-ML (5 and 1.2%, v/v), the percentage of apoptotic cells was reduced (±30%). For the H2O2 assay, the percentage of cells in necrosis was reduced by 40% after exposure to NE-ML1% (v/v) + H2O2 2 mM. The protective effects and increased permeation of macela nanoemulsion make this a promising new candidate for bovine mastitis therapy.

In this study, we investigated the feasibility to obtain nanoparticles (NPs) by assembling pramlintide (Pram) with dextran sulfate (DexS), as a new approach for mucosal peptide delivery. DexS/Pram NPs were prepared by dropwise addition of a Pram solution to a DexS solution under magnetic stirring. The physicochemical characteristics of NPs and molecular interactions involved in the co-assembling were evaluated by dynamic light scattering (DLS), transmission electronic microscopy (TEM), isothermal titration microcalorimetry, Fourier-transform infrared spectroscopy (FTIR), fluorescence quenching, and circular dichroism (CD). DexS/Pram NPs displayed a narrow size distribution (ca. 200 nm), negative zeta potential (ca. −40 mV), association efficiency close to 100%, and nanogel behavior. The assembling with DexS increased the Pram α-helical content, stabilizing the peptide in its bioactive form. The colloidal stability of nanoparticles was dependent on the salt concentration and it could be assumed that peptide release from nanoparticles occurs by dissociation of the complex at physiological conditions.

This study proposes a novel blend of drying adjuvants (lactose and polyvinylpyrrolidone) as an approach to produce dispersible powders containing nanocapsules for the development of skin delivery s...

The in vitro assessment of drug release from polymeric nanocapsules suspensions is one of the most studied parameters in the development of drug-loaded nanoparticles. Nevertheless, official methods for the evaluation of drug release from submicrometric carriers are not available. In this work, a new approach to assess the in vitro drug release profile from drug-loaded lipid-core nanocapsules (LNC) was proposed. A continuous-flow system (open system) was designed to evaluate the in vitro drug release profiles from different LNC formulations containing prednisolone or clobetasol propionate (LNC-CP) as drug model (LNC-PD) using a homemade apparatus. The release medium was constantly renewed throughout the experiment. A dialysis bag containing 5 mL of formulation (0.5 mg mL(-1)) was maintained inside the apparatus, under magnetic stirring and controlled temperature (37°C). In parallel, studies based on the conventional dialysis sac technique (closed system) were performed. It was possible to discriminate the in vitro drug release profile of different formulations using the open system. The proposed strategy improved the sink condition, by constantly renewing the release medium, thus maintaining the drug concentration farther from the saturated concentration in the release medium. Moreover, problems due to sampling errors can be easily overcome using this semi-automated system, since the collection is done automatically without interference from the analyst. The system proposed in this paper brings important methodological and analytical advantages, becoming a promising prototype semi-automated apparatus for performing in vitro drug release studies from drug-loaded lipid-core nanocapsules and other related nanoparticle drug delivery systems.