Azithromycin Cationic Non-Lecithoid Nano/Microparticles Improve Bioavailability and Targeting Efficiency

Chitosan Nanoparticles Modified by Anredera cordifolia (Ten.) Steenis Leaf Extract for Enhancement of Azithromycin Encapsulation Efficiency and Loading Capacity: In vitro Drug Release Study

The encapsulation efficiency and the loading capacity of azithromycin (AZI) were succesfully enhanced by modifying chitosan nanoparticle (NCh) with Anredera cordifolia leaf extract (ACLE), as demonstrated in this study. The prominent secondary metabolites in ACLE could establish a new chemical bonds with NCh's amino groups and partly improved the hydrophobicity of NCh, which leads to excellent AZI encapsulation efficiency and loading capacity of 95.24 ± 1.30% and 55.74 ± 1.03%, respectively. TEM characterization demonstrated that the AZI-loaded ACLE-NCh nanoparticles were uniformly distributed with a particle size of 24.6 ± 2.9 nm. According to the result of in vitro drug release studies, AZI-loaded ACLE-NCh releases 1.12 ± 0.33% at a pH of 1.6 for 2 h, 82.05 ± 2.26% at a pH of 6.8 for 6 h, and 93.44 ± 1.94% at a pH of 7.4 for 24 h. It is remarkable that the encapsulation activityu of AZI-loaded ACLE-NCh is more effective due to the better interaction between NCh and AZI resulting from the increased hydrophobicity of modified NCh. Moreover, this work provides novel findings on the significant contribution of NCh modified by plant extracts, which has the potential as a carrier for azithromycin.

Delivering macrolide antibiotics to heal a broken heart - And other inflammatory conditions

Drug carriers to deliver macrolide antibiotics, such as azithromycin, show promise as antibacterial agents. Macrolide drug carriers have largely focused on improving the drug stability and pharmacokinetics, while reducing adverse reactions and improving antibacterial activity. Recently, macrolides have shown promise in treating inflammatory conditions by promoting a reparative effect and limiting detrimental pro-inflammatory responses, which shifts the immunologic setpoint from suppression to balance. While macrolide drug carriers have only recently been investigated for their ability to modulate immune responses, the previous strategies that deliver macrolides for antibacterial therapy provide a roadmap for repurposing the macrolide drug carriers for therapeutic interventions targeting inflammatory conditions. This review describes the antibacterial and immunomodulatory activity of macrolides, while assessing the past in vivo evaluation of drug carriers used to deliver macrolides with the intention of presenting a case for increased effort to translate macrolide drug carriers into the clinic.

Antiviral Drug Delivery System for Enhanced Bioactivity, Better Metabolism and Pharmacokinetic Characteristics

Antiviral drugs (AvDs) are the primary resource in the global battle against viruses, including the recent fight against corona virus disease 2019 (COVID-19). Most AvDs require multiple medications, and their use frequently leads to drug resistance, since they have poor oral bioavailability and low efficacy due to their low solubility/low permeability. Characterizing the in vivo metabolism and pharmacokinetic characteristics of AvDs may help to solve the problems associated with AvDs and enhance their efficacy. In this review of AvDs, we systematically investigated their structure-based metabolic reactions and related enzymes, their cellular pharmacology, and the effects of metabolism on AvD pharmacodynamics and pharmacokinetics. We further assessed how delivery systems achieve better metabolism and pharmacology of AvDs. This review suggests that suitable nanosystems may help to achieve better pharmacological activity and pharmacokinetic behavior of AvDs by altering drug metabolism through the utilization of advanced nanotechnology and appropriate administration routes. Notably, such AvDs as ribavirin, remdesivir, favipiravir, chloroquine, lopinavir and ritonavir have been confirmed to bind to the severe acute respiratory syndrome-like coronavirus (SARS-CoV-2) receptor and thus may represent anti-COVID-19 treatments. Elucidating the metabolic and pharmacokinetic characteristics of AvDs may help pharmacologists to identify new formulations with high bioavailability and efficacy and help physicians to better treat virus-related diseases, including COVID-19.

Recent Advances in Oral Nano-Antibiotics for Bacterial Infection Therapy

Bacterial infections are the main infectious diseases and cause of death worldwide. Antibiotics are used to treat various infections ranging from minor to life-threatening ones. The dominant route to administer antibiotics is through oral delivery and subsequent gastrointestinal tract (GIT) absorption. However, the delivery efficiency is limited by many factors such as low drug solubility and/or permeability, gastrointestinal instability, and low antibacterial activity. Nanotechnology has emerged as a novel and efficient tool for targeting drug delivery, and a number of promising nanotherapeutic strategies have been widely explored to overcome these obstacles. In this review, we explore published studies to provide a comprehensive understanding of the recent progress in the area of orally deliverable nano-antibiotic formulations. The first part of this article discusses the functions and underlying mechanisms by which nanomedicines increase the oral absorption of antibiotics. The second part focuses on the classification of oral nano-antibiotics and summarizes the advantages, disadvantages and applications of nanoformulations including lipid, polymer, nanosuspension, carbon nanotubes and mesoporous silica nanoparticles in oral delivery of antibiotics. Lastly, the challenges and future perspective of oral nano-antibiotics for infection disease therapy are discussed. Overall, nanomedicines designed for oral drug delivery system have demonstrated the potential for the improvement and optimization of currently available antibiotic therapies.

Abdulbaqi I, Seok Ming T, Siok Yee C, A. Wahab H, Asif SM, Darwis Y. Liquid and Solid Self-Emulsifying Drug Delivery Systems (SEDDs) as Carriers for the Oral Delivery of Azithromycin: Optimization, In Vitro Characterization and Stability Assessment

Azithromycin (AZM) is a macrolide antibiotic used for the treatment of various bacterial infections. The drug is known to have low oral bioavailability (37%) which may be attributed to its relatively high molecular weight, low solubility, dissolution rate, and incomplete intestinal absorption. To overcome these drawbacks, liquid (L) and solid (S) self-emulsifying drug delivery systems (SEDDs) of AZM were developed and optimized. Eight different pseudo-ternary diagrams were constructed based on the drug solubility and the emulsification studies in various SEDDs excipients at different surfactant to co-surfactant (Smix) ratios. Droplet size (DS) < 150 nm, dispersity (Đ) ≤ 0.7, and transmittance (T)% > 85 in three diluents of distilled water (DW), 0.1 mM HCl, and simulated intestinal fluids (SIF) were considered as the selection criteria. The final formulations of L-SEDDs (L-F1(H)), and S-SEDDs (S-F1(H)) were able to meet the selection requirements. Both formulations were proven to be cytocompatible and able to open up the cellular epithelial tight junctions (TJ). The drug dissolution studies showed that after 5 min > 90% and 52.22% of the AZM was released from liquid and solid SEDDs formulations in DW, respectively, compared to 11.27% of the pure AZM, suggesting the developed SEDDs may enhance the oral delivery of the drug. The formulations were stable at refrigerator storage conditions.

Polymeric Inserts Containing Eudragit® L100 Nanoparticle for Improved Ocular Delivery of Azithromycin

Polymeric inserts containing azithromycin-loaded Eudragit^® L100 nanoparticles were developed to sustain the drug release and enhance its ocular performance. The solvent diffusion technique was employed to prepare nanoparticles. The developed nanoparticles (NPs) were fully characterized and investigated. The solvent casting method was used to prepare azithromycin ocular inserts (azithromycin, AZM film) by adding hydroxypropyl methylcellulose (HPMC) or hydroxyethyl cellulose (HEC) solutions after the incorporation of AZM-loaded Eudragit^® L100 nanoparticles into plasticized PVA (polyvinyl alcohol) solutions. The optimized nanoparticles had a particle size of 78.06 ± 2.3 nm, zeta potential around −2.45 ± 0.69 mV, polydispersity index around 0.179 ± 0.007, and entrapment efficiency 62.167 ± 0.07%. The prepared inserts exhibited an antibacterial effect on Staphylococcus aureus and Escherichia coli cultures. The inserts containing AZM-loaded nanoparticles showed a burst release during the initial hours, followed by a sustained drug release pattern. Higher cumulative corneal permeations from AZM films were observed for the optimized formulation compared to the drug solution in the ex-vivo trans-corneal study. In comparison to the AZM solution, the inserts significantly prolonged the release of AZM in rabbit eyes (121 h). The mucoadhesive inserts containing azithromycin-loaded Eudragit^® L100 nanoparticles offer a promising approach for the ocular delivery of azithromycin (antibacterial and anti-inflammatory) to treat ocular infections that require a prolonged drug delivery.

Biomimetic polysaccharide-cloaked lipidic nanovesicles/microassemblies for improving the enzymatic activity and prolonging the action time for hyperuricemia treatment

The improvement and maintenance of enzymatic activities represent major challenges. However, to address these we developed novel biomimetic polysaccharide hyaluronan (Hn)-cloaked lipidic nanovesicles (BHLN) and microassemblies (BHLNM) as enzyme carriers that function by entrapping enzymes in the core or by tethering them to the inner/outer surfaces via covalent interactions. The effectiveness of these enzyme carriers was demonstrated through an evaluation of the enzymatic activity and anti-hyperuricemia bioactivity of urate oxidase (also called uricase, Uase). We showed that Uase was effectively loaded within the BHLN/BHLNM (UHLN/UHLNM) and maintained good enzymatic bioactivity through a range of effects, including isolation from the external environment due to the vesicle-carrying (shielding effect), avoidance of recognition by the reticuloendothelial system due to Hn-cloaking (long-term effect), production of beneficial conformational changes (allosteric effect) due to a favorable internal microenvironment of construction and vesicle loading, and stabilization due to the reversible conjugation of Uase or vesicle and serum albumin (deposit effect). UHLN/UHLNM had significantly increased bioavailability (∼533% and ∼331% compared to Uase) and demonstrated greatly improved efficacy, whereby the time required for UHLN/UHLNM to lower the plasma uric acid concentration to a normal level was much shorter than that for free Uase. The interactions of the therapeutic enzyme (Uase), biomimetic membrane components (Hn and phospholipid), and serum albumin were investigated with a fluorescent probe and computational simulations to help understand the superior properties of UHLN/UHLNM.

Natural Oral Anticancer Medication in Small Ethanol Nanosomes Coated with a Natural Alkaline Polysaccharide

Oral medication is the most acceptable therapy to treat chronic diseases. Natural drugs and excipients have unique advantages, such as low cost and high safety. We first investigated modified ethanol nanosomes for tumor treatment via oral administration. We loaded curcumin (CM) into small ethanol nanosomes coated with the natural alkaline polysaccharide chitosan (CCSET) for increased absorption and bioavailability and enhanced efficacy against small cell lung cancer (SCLC). Compared to CM and noncoated ethanol nanosomes, CCSETs exhibited superior physicochemical, in vitro-in vivo kinetic, and absorptive properties and treatment efficacy at the cellular and animal levels. The interaction of CM and serum albumin (the quantitative binding force) was analyzed. The bioavailability of CCSET increased by 11.84-fold and the tumor growth inhibition rate increased markedly compared to CM. We first confirmed the effect of CM on SCLC stem cells, and CCSET greatly enhanced this action. We first reported that CM had an antitumor effect on SCLC at the animal level and that CCSET enhanced this effect. Natural alkaline polysaccharide-coated small ethanol nanosomes delivering natural medicine may be a potential oral anticancer strategy.

Bioavailability Enhancement of Poorly Soluble Drugs: The Holy Grail in Pharma Industry

Background:

Bioavailability, one of the prime pharmacokinetic properties of a drug, is defined as the fraction of an administered dose of unchanged drug that reaches the systemic circulation and is used to describe the systemic availability of a drug. Bioavailability assessment is imperative in order to demonstrate whether the drug attains the desirable systemic exposure for effective therapy. In recent years, bioavailability has become the subject of importance in drug discovery and development studies.

Methods:

A systematic literature review in the field of bioavailability and the approaches towards its enhancement have been comprehensively done, purely focusing upon recent papers. The data mining was performed using databases like PubMed, Science Direct and general Google searches and the collected data was exhaustively studied and summarized in a generalized manner.

Results:

The main prospect of this review was to generate a comprehensive one-stop summary of the numerous available approaches and their pharmaceutical applications in improving the stability concerns, physicochemical and mechanical properties of the poorly water-soluble drugs which directly or indirectly augment their bioavailability.

Conclusion:

The use of novel methods, including but not limited to, nano-based formulations, bio-enhancers, solid dispersions, lipid-and polymer-based formulations which provide a wide range of applications not only increases the solubility and permeability of the poorly bioavailable drugs but also improves their stability, and targeting efficacy. Although, these methods have drastically changed the pharmaceutical industry demand for the newer potential methods with better outcomes in the field of pharmaceutical science to formulate various dosage forms with adequate systemic availability and improved patient compliance, further research is required.

Role of nanostructures in improvising oral medicine

The most preferable mode of drugs administration is via the oral route but physiological barriers such as pH, enzymatic degradation etc. limit the absolute use of this route. Herein lies the importance of nanotechnology having a wide range of applications in the field of nano-medicine, particularly in drug delivery systems. The exclusive properties particularly small size and high surface area (which can be modified as required), exhibited by these nanoparticlesrender these structures more suitable for the purpose of drug delivery. Various nanostructures, like liposomes, dendrimers, mesoporous silica nanoparticles, etc. have been designed for the said purpose. These nanostructures have several advantages over traditional administration of medicine. Apart from overcoming the pharmacokinetic and pharmacodynamics limitations of many potential therapeutic molecules, they may also be useful for advanced drug delivery purposes like targeted drug delivery, controlled release, enhanced permeability and retention (EPR) effect. In this review, we attempt to describe an up-to-date knowledge on various strategically devised nanostructures to overcome the problems related to oral drug administration.

Catan-ionic hybrid lipidic nano-carriers for enhanced bioavailability and anti-tumor efficacy of chemodrugs

To date there has not been any report on catan-ionic hybrid lipidic nano-carriers, let alone a report on applying them to deliver insoluble anti-tumor drugs. Catan-ionic hybrid lipidic nano-carriers containing curcumin (CUR-C-HLN) inherit the merits of catan-ionic systems, hybrid lipidic systems and nano-structured carriers (the second-generation substitute of solid lipidic nano-systems). Catan-ionic surfactants increased microvesicle stabilization by producing unordered isometric clusters, enhanced absorptive amount as an inhibitor of enzyme and protein, improved tumor accumulation by cellular endocytosis and membranous fusion; hybrid lipids helped to obtain high drug content and low leakage by forming a less-organized matrix arrangement. CUR-C-HLN favorably changed absorptive and pharmacokinetic properties after oral and/or intravenous administrations; improved cell growth inhibition, apoptotic inducing and anti-invasion effects; enhanced antitumor efficiency and reduced cancerous growth. Catan-ionic hybrid lipidic nano-carriers provide an alternative good choice for effective delivery of anticancerous chemodrugs.

Efficient intracellular delivery makes cancer cells sensitive to nanoemulsive chemodrugs

Evodiamine has been documented to possess activities in numerous cancer cells. Our preliminary study showed that A549 cells were insensitive to evodiamine. In this paper, A549 cells are sensitive to nanoemulsive evodiamine (EVONE) through an efficient intracellular and systematic delivery. EVONE entered tumor cells by energy-dependent and mainly through clathrin-mediated endocytosis. EVONE exerted a higher cytotoxicity in a dose- and time-dependent manner. The enhanced induction of cell cycle arrest was ascribed to the down-regulation of cyclin B and cyclin dependent kinase 1, while the enhanced induction of apoptosis was due to the activation of caspase −3, −8 and −9 and the decreased B-cell lymphoma 2/ assaciated X protein ratio. Furthermore, the in vivo kinetic, bioavailability and in situ absorption characteristics of EVONE were much better than those of free evodiamine. The cancer cells insensitive to free chemodrugs became sensitive to nanoemulsive chemodrugs.

Non-Ionic Surfactant Vesicles (Niosomes) as New Drug Delivery Systems

Lipid vesicular systems composed of hydrated amphihiles with or without bilayer inducing agents such as cholesterol. On the basis of used amphiphilic molecule different nomenclature are used as liposomes, ufasomes and niosomes. Nonionic surfactants with mono-, di- or trialkyl chains form niosomes which are lipid vesicles with more chemical stability in comparison with phospholipids of liposomes. Both hydrophobic and hydrophilic chemicals can be encapsulated in niosomes as a new drug delivery system. This drug carrier system could have administered via injection, oral, pulmonary, vaginal, rectal, ophthalmic, nasal or transdermal routes with penetration enhancing potential. This chapter presents a detailed explain about niosome forming components, methods of preparation and routes of administration. Many examples for drug delivery potential of niosomes are also available in this review. Vaccine adjuvant and genetic substances vector capabilities are not given here.

Non-Ionic Surfactant Vesicles (Niosomes) as New Drug Delivery Systems

Lipid vesicular systems composed of hydrated amphihiles with or without bilayer inducing agents such as cholesterol. On the basis of used amphiphilic molecule different nomenclature are used as liposomes, ufasomes and niosomes. Nonionic surfactants with mono-, di- or trialkyl chains form niosomes which are lipid vesicles with more chemical stability in comparison with phospholipids of liposomes. Both hydrophobic and hydrophilic chemicals can be encapsulated in niosomes as a new drug delivery system. This drug carrier system could have administered via injection, oral, pulmonary, vaginal, rectal, ophthalmic, nasal or transdermal routes with penetration enhancing potential. This chapter presents a detailed explain about niosome forming components, methods of preparation and routes of administration. Many examples for drug delivery potential of niosomes are also available in this review. Vaccine adjuvant and genetic substances vector capabilities are not given here.

Novel nanoemulsion based lipid nanosystems for favorable in vitro and in vivo characteristics of curcumin

The goal of this study was to assess the enhanced elementary characteristics, in vitro release, anti-cancer cytotoxicity, in situ absorption and in vivo bioavailability of a novel nanoemulsion based lipid nanosystems containing curcumin (CNELNs) when administered orally. The CNELNs were first fabricated by loading water-in-oil nanoemulsions into lipid nanosystems using a nanoemulsion-film dispersion-sonication method. The gastro-intestinal absorption, in vitro release and in vivo kinetic property of CNELNs were investigated using an in situ perfusion method, a dialysis method and a concentration-time curve based method, respectively. The inhibitory effects of CNELNs on human lung cancer A549 cell growth were determined using MTT assay. The absorption constants and effective permeabilities of CNELNs in different gastro-intestinal tracts increased 2.29-4.04 times and 4.06-8.27 times that of curcumin (CUR), respectively. The relative bioavailability of CNELNs to free CUR was 733.59%. CNELNs inhibited A549 growth in a dose- and time-dependent manner. CNELNs markedly improved the oral bioavailability of CUR which was probably due to the increased gastro-intestinal absorption. CNELNs had stronger inhibitory effects on the viabilities of A549 cells than that of free CUR. CNELNs might be promising nanosystems for oral delivery of CUR to satisfy clinical requirements.

Catanionic lipid nanosystems improve pharmacokinetics and anti-lung cancer activity of curcumin

Novel catanionic lipid nanosystems (CLNs) incorporating curcumin (CCM) were developed, and improvements in pharmacokinetics and enhanced anti-lung cancer activity were observed. CCM was present in a lipid matrix surrounded by cationic, anionic and zwitterionic surfactants, forming the core-shell nanosystems. Compared with free CCM, the CCM-CLNs had much higher oral and intravenous bioavailabilities due to enhanced absorption and reduced clearance. The CCM-CLNs exhibited greater cytotoxicity in Lewis lung cancer (LLC) cells, which might have been due to increased antiproliferative, proapoptotic and anti-invasive activities and induction of cell cycle arrest. The CCM-CLNs increased the antitumor efficacy of CCM and decreased the tumor growth rate in tumor-bearing mice. This is the first report of induction of apoptosis in LLC cells by CCM through the PI3K/Akt/FoxO1/Bim signaling pathway. Catanionic lipid nanocarriers show promise for the therapeutic delivery of insoluble anti-tumor drugs.

Functional nanoemulsion-hybrid lipid nanocarriers enhance the bioavailability and anti-cancer activity of lipophilic diferuloylmethane

The purpose of this study was to assess the enhanced physicochemical characteristics, in vitro release behavior, anti-lung cancer activity, gastrointestinal absorption, in vivo bioavailability and bioequivalence of functional nanoemulsion-hybrid lipid nanocarriers containing diferuloylmethane (DNHLNs). The DNHLNs were first fabricated by loading water-in-oil nanoemulsions into hybrid lipid nanosystems using nanoemulsion-thin film-sonication dispersion technologies. The in situ absorption and in vitro and in vivo kinetic features of DNHLNs were measured using an in situ unidirectional perfusion method, a dynamic dialysis method and a plasma concentration-time profile-based method, respectively. The cytotoxic effects of DNHLNs in lung adenocarcinoma A549 cells were examined using MTT colorimetric analysis. The absorptive constants and permeabilities of DNHLNs in four gastrointestinal sections increased by 1.43-3.23 times and by 3.10-7.76 times that of diferuloylmethane (DIF), respectively. The relative bioavailability of DNHLNs to free DIF was 855.02%. DNHLNs inhibited cancer cell growth in a time- and dose-dependent manner. DNHLNs markedly improved the absorption and bioavailability of DIF after oral administration. DNHLNs had stronger inhibitory effects on the viability of A549 cells than that of free DIF. DNHLNs might be potentially promising nanocarriers for DIF delivery via the oral route to address unmet clinical needs.

Nanosomal Microassemblies for Highly Efficient and Safe Delivery of Therapeutic Enzymes

Enzyme therapy has unique advantages over traditional chemotherapies for the treatment of hyperuricemia, but overcoming the delivery obstacles of therapeutic enzymes is still a significant challenge. Here, we report a novel and superior system to effectively and safely deliver therapeutic enzymes. Nanosomal microassemblies loaded with uricase (NSU-MAs) are assembled with many individual nanosomes. Each nanosome contains uricase within the alkaline environment, which is beneficial for its catalytic reactions and keeps the uricase separate from the bloodstream to retain its high activity. Compared to free uricase, NSU-MAs exhibited much higher catalytic activity under physiological conditions and when subjected to different temperatures, pH values and trypsin. NSU-MAs displayed increased circulation time, improved bioavailability, and enhanced uric acid-lowering efficacy, while decreasing the immunogenicity. We also described the possible favorable conformational changes occurring in NSU-MAs that result in favorable outcomes. Thus, nanosomal microassemblies could serve as a valuable tool in constructing delivery systems for therapeutic enzymes that treat various diseases.