Insulin-loaded alginic acid nanoparticles for sublingual delivery

Abstract

Alginic acid nanoparticles (NPs) containing insulin, with nicotinamide as permeation enhancer were developed for sublingual delivery. The lower concentration of proteolytic enzymes, lower thickness and enhanced retention due to bioadhesive property, were relied on for enhanced insulin absorption. Insulin-loaded NPs were prepared by mild and aqueous based nanoprecipitation process. NPs were negatively charged and had a mean size of ～200?nm with low dispersity index. Insulin loading capacities of >95% suggested a high association of insulin with alginic acid. Fourier Transform Infra-Red Spectroscopy (FTIR) spectra and DSC (Differential Scanning Calorimetry) thermogram of insulin-loaded NPs revealed the association of insulin with alginic acid. Circular dichroism (CD) spectra confirmed conformational stability, while HPLC analysis confirmed chemical stability of insulin in the NPs. Sublingually delivered NPs with nicotinamide exhibited high pharmacological availability (>100%) and bioavailability (>80%) at a dose of 5?IU/kg. The high absolute pharmacological availability of 20.2% and bioavailability of 24.1% in comparison with subcutaneous injection at 1?IU/kg, in the streptozotocin-induced diabetic rat model, suggest the insulin-loaded alginic acid NPs as a promising sublingual delivery system of insulin.     

Omega-3 Fatty Acids and Their Interaction with the Gut Microbiome in the Prevention and Amelioration of Type-2 Diabetes

Type-2 diabetes mellitus (T2DM) is often linked with hyperglycemia, disturbed lipid profiles, inflammation, and gut dysbiosis. Omega-3 fatty acid supplementation has a vital role in the management of T2DM. As a result, a better understanding of the potential role of omega-3 fatty acids in the development and progression of T2DM by influencing the intestinal microflora will help to improve the therapeutic intervention for T2DM and related complications. Focusing on the molecular mechanisms and signaling pathways induced by omega-3 fatty acids, this paper attempts to comprehensively review and discuss the putative associations between omega-3 fatty acids, gut dysbiosis, and the pathophysiology of T2DM and its related comorbidities. In addition, we contemplate the importance of gut microbiota in T2DM prevention and treatment and ponder the role of omega-3 fatty acids in T2DM by positively modulating gut microbiota, which may lead to discovery of novel targets and therapeutic strategies thereby paving way for further comprehensive, mechanistic, and clinical studies.     

Design,synthesis and docking study of Vortioxetine derivatives as a SARS-CoV-2 main protease inhibitor

PurposeVortioxetine an anti-depressant FDA-drug recently reported showing better in vitro efficacy against SARS-CoV-2.MethodsIn this study, we have synthesized ten new derivatives having alkenes, alkynes, benzyl, aryl, and mixed carbamate at the N-terminal of vortioxetine. Then the binding energy and interactions with the crucial amino acid residues in the binding pocket of main protease (M^pro) of SARS-CoV-2, of reported and ten newly synthesized vortioxetine derivatives (total thirty-one) in comparison with remdesivir are analyzed and presented in this paper.ResultsBased on the docking scores predicted by ADV and AD, most vortioxetine derivatives showed better binding efficiency towards M^pro of SARS-CoV-2 in comparison with remdesivir (an EUA approved drug against SARS-CoV-2 M^pro) and vortioxetine.ConclusionThis study shows that some vortioxetine derivatives can be developed into promising drugs for COVID-19 treatment.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40199-022-00441-z.     

Evaluation of cytotoxic, oxidative stress, proinflammatory and genotoxic responses of micro- and nano-particles of dolomite on human lung epithelial cells A(549)

Dolomite is a natural mineral of great industrial importance and used worldwide, thus millions of workers are at risk of occupational exposure. Its toxicity is however, meagerly documented. In the present investigation, a dolomite powder obtained from its milling unit was analyzed by some standard methods namely, optical microscopy, transmission electron microscopy and dynamic light scattering. Results showed that dolomite powder contained particles of different shapes and size both microparticles (MPs) and nanoparticles (NPs), suggesting potential occupational exposure of these particles. An attempt was therefore, made to investigate dolomite toxicity in a particle size-dependent manner in human lung epithelial cells A(549). The comparative toxicity evaluation of MPs and NPs was carried out by assessing their effects on cell viability, membrane damage, glutathione, reactive oxygen species (ROS), lipid peroxidation (LPO), micronucleus (MN) and proinflammatory cytokines, namely tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). These markers of cytotoxicity, genotoxicity and inflammation were assayed in cells exposed to MPs and NPs in a dose-and time-dependent manner. Invariably, their toxic effects were dose-and time-dependent while NPs in general were significantly more toxic. Notably, NPs caused oxidative stress, genotoxicity and inflammatory responses, as seen by significant induction of ROS, LPO, MN, TNF-α, IL-1β and IL-6. Thus, the study tends to suggest that separate health safety standards would be required for micrometer and nanometer scale particles of dolomite.     

Selective HPLC Method Development for Soy Phosphatidylcholine Fatty Acids and Its Mass Spectrometry

A novel, efficient and simple approach for soy phosphatidylcholine analysis according to its fatty acid composition was studied with reverse-phase high-performance liquid chromatography. The reverse-phase high-performance liquid chromatography analysis was performed isocratically using UV detector and simple mobile phase solvents consisting of isopropyl alcohol, methanol, and deionized water in the proportion of 70:8:22 v/v. The uniqueness of the proposed method was the separation of individual fatty acids of soy phosphatidylcholine. The high-performance liquid chromatography method for soy phosphatidylcholine was validated for linearity with correlation coefficient of above 0.99 for all the peaks separated according to their fatty acid composition. The intra-day and the inter-day precision studies provided the relative standard deviation of less than 2%. The limit of detection and limit of quantitation values were also calculated for all the resolved peaks of soy phosphatidylcholine. Also system performance parameters such as number of theoretical plates, capacity factor, tailing factor, separation factor, and peak resolution were studied systematically and found well within the acceptable range. The proposed high-performance liquid chromatography method was successfully applied to soy phosphatidylcholine extracted and purified from deoiled soy lecithin without any interference of impurities or solvent peaks. Individually, the collected peaks of sample soy phosphatidylcholine were subjected for mass spectroscopy. The mass spectra showed all the peaks having different saturated or unsaturated fatty acid chains attached to glyerophosphocholine moiety of soy phosphatidylcholine. The method developed is economic and well suited for estimation of soy phosphatidylcholine with its fatty acid composition.     

Properties of electromagnetic field focusing probe

The electromagnetic field focusing (EFF) apparatus consists of a radio frequency generator, solenoidal coil, and a hand-held or catheter probe. Applications such as aneurysm treatment, angioplasty, and neurosurgery in various models have been reported. The probe is operated in the near field (within one wavelength of an electromagnetic field source) of a coil inducing eddy currents in biological tissues, producing maximal convergence of the induced current at the probe tip. The probe produces very high temperatures depending on the wattage selected for the given radio frequency of output power. The high temperature can be used in cutting, cauterizing, or vaporizing. The EFF probe is comparable to different types of lasers and to bipolar and monopolar cautery. The EFF probe can be used with catheters or endoscopes. Objectives of this study were to determine what the thermal properties of the EFF probe are and how instrument parameters can be varied to obtain different temperatures in the tissue near the probe tip. In this study an F2 catheter was used as an insulated sheath and the tip of the guide wire was used as the probe tip. Different powers, wave forms, coil-to-probe distances, and probe-tip lengths were tested on a phantom that simulates tissue electrical properties. Some of the experiments were conducted under normal saline to simulate treatment of tissue with body fluids such as blood vessels or brain tissue under normal physiologic conditions. It is concluded that the EFF probe has the advantages of easy manipulation, relative safety, cost effectiveness, and a high degree of spatial control.(ABSTRACT TRUNCATED AT 250 WORDS)     

Formulation development,in vitro and in vivo evaluation of microemulsion-based gel loaded with ketoprofen

Abstract

Background: Anti-inflammatory agents are widely used to relieve inflammation caused by various factors.

Aim: This study was initiated with the intention to deliver low aqueous soluble ketoprofen to enhance its solubility by developing microemulsion system as a template and then incorporating it into gel phase.

Materials and methods: Initially ketoprofen was solubilized into microemulsion preparation made up of clove oil, Tween 20 and propylene glycol as oil phase, surfactant and co-surfactant respectively, then it was incorporated into different concentration of gelling phase using gelling agents namely Carbopol 940, Carbopol 934 and hydroxypropyl methyl cellulose K₄M (HPMC K₄M). Formulated emulgels were evaluated for their physical appearance, pH, rheological properties, globule size, extrudability, drug content, spreadability, bioadhesion strength, in vitro and ex vivo drug release, skin irritation test and anti-inflammatory activity.

Results: Microemulsion had shown globule size 396?nm, pH 6–6.7, viscosity 29.4?cps and zeta potential ?12?mV indicating good stability. Formulated emulgels showed good physical appearance, skin acceptable pH 6–6.9, non-Newtonian shear thinning system, drug content 99.28?±?0.16%, bioadhesion strength 48.4 gram force, globule size 473?nm, spreadability 22.96?gm.cm/s, good extrudability, in vitro release, ex vivo release did not showed any irritation reaction and possess a good anti-inflammatory activity.

Conclusions: Selected batch showed enhanced drug release (92.42?±?4.66%) as compared to marketed gel (65.94?±?3.30). Similarly ex vivo release of formulation showed 72.22% release through mice skin compared with marketed gel. Formulations followed Korsmeyer–Peppas diffusion kinetic model. It was observed from the results that the formulated emulgel can provide promising delivery of ketoprofen.     

Engineering of polymer–surfactant nanoparticles of doxycycline hydrochloride for ocular drug delivery

Abstract

Context: Physiologic barriers of the eye, short precorneal drug residence time and poor corneal penetration are the few reasons for reduced ocular bioavailability.

Objective: This study was aimed to develop novel polymer–surfactant nanoparticles of hydrophilic drug doxycycline hydrochloride (DXY) to improve precorneal residence time and drug penetration.

Materials and methods: Nanoparticles were formulated using emulsion cross-linking method and the formulation was optimized using factorial design. The prepared formulation was characterized for particle size, ζ potential, encapsulation efficiency, in vitro drug release and ex vivo drug diffusion studies. The antibacterial activity studies were also carried out against Escherichia coli and Staphylococcus aureus using the cup-plate method. In vivo eye irritation study was carried out by a modified Draize test in rabbits.

Results and discussion: The particle size was found to be in the range of 331–850?nm. About 45–80% of the drug was found to be encapsulated in the nanoparticles. In vitro release demonstrated sustained release profile. Lower flux values in case of nanoparticles as compared to DXY pure drug solution in ex vivo diffusion studies confirmed the sustained release. The nanoparticles were found to be significantly effective (p?<?0.001) than DXY aqueous solution due to sustained release of doxycycline from nanoparticles in both the E. coli and S. aureus strains. The formulation was found to be stable over entire stability period.

Conclusion: The developed formulation is safe and suitable for sustained ocular drug delivery.