Improved oral bioavailability of myricitrin by liquid self-microemulsifying drug delivery systems

Advanced Delivery Strategies of Nintedanib for Lung Disorders and Beyond: A Comprehensive Review

Nintedanib, a primary treatment for lung fibrosis, has gathered substantial attention due to its multifaceted potential. A tyrosine kinase inhibitor, nintedanib, inhibits multiple signalling receptors, including endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR), and fibroblast growth factor receptor (FGFR) and ultimately inhibits fibroblast proliferation and differentiation. Therefore, nintedanib has been studied widely for other ailments like cancers and hepatic fibrosis, apart from lung disorders. Commercially, nintedanib is available as soft gelatin capsules for treatment against idiopathic pulmonary fibrosis. Since it has very low oral bioavailability (4.7%), high doses of a drug, such as 100-150 mg, are administered, which can cause problems of gastrointestinal irritation and hepatotoxicity. The article begins with exploring the mechanism of action of nintedanib, elucidating its complex interactions within cellular pathways that govern fibrotic processes. It also emphasizes the pharmacokinetics of nintedanib, clinical trial insights, and the limitations of conventional formulations. The article mainly focuses on the emerging landscape of nanoparticle-based carriers such as hybrid liposome-exosome, nano liquid crystals, discoidal polymeric, and magnetic systems, offering promising avenues to optimize drug targeting, address its efficacy issues and minimise adverse effects. However, none of these delivery systems are commercialised, and further research is required to ensure safety and effectiveness in clinical settings. Yet, as research progresses, these advanced delivery systems promise to revolutionise the treatment landscape for various fibrotic disorders and cancers, potentially improving patient outcomes and quality of life.

Improving cellular uptake and synergetic anti-tumor effects of magnolol and Brucea javanica oil through self-microemulsion

OBJECTIVE

Magnolol (MG) and Brucea javanica (L.) Merr. oil (BJO) possess synergetic anti-tumor effects, but have poor water solubility and stability, which results in low oral bioavailability.

SIGNIFICANCE

The MG loaded self-microemulsion drug delivery system (MG-SMDDS) with BJO as oil phase component was utilized to improve the cellular uptake and synergetic anti-tumor effects.

METHODS

Compatibility study and pseudoternary phase diagram (PTPD) were respectively employed to screen for the composition and proportion of oil phase in the formulation. Central composite design-effect surface method was applied to optimize proportion of each formulation condition. The droplet size, ζ-potential, colloid stability, encapsulation rate (ER) and in vitro dissolution rate of MG-SMDDS were evaluated. Furthermore, cellular uptake and cytotoxicity of the microemulsion on HepG2 cells were assessed.

RESULTS

The optimal composition of MG-SMDDS was: MG (9.09%), castor oil (7.40%), BJO (2.47%), Cremophor EL 35 (54.04%) and 1, 2-propanediol (27.01%). The MG-SMDDS exhibited satisfactory droplet size, ζ-potential, colloid stability and ER, as well as faster dissolution rate than free MG. More importantly, SMEDDS containing BJO could enhance the cellular uptake and cytotoxicity of free BJO and free MG on tumor cells.

CONCLUSIONS

The BJO self-microemulsion delivery technique can provide an idea for design of oral delivery vehicles based on BJO.

Development of a self-microemulsifying drug delivery system to deliver delamanid via a pressurized metered dose inhaler for treatment of multi-drug resistant pulmonary tuberculosis

Tuberculosis (TB) is a serious health issue that contributes to millions of deaths throughout the world and increases the threat of serious pulmonary infections in patients with respiratory illness. Delamanid is a novel drug approved in 2014 to deal with multi-drug resistant TB (MDR-TB). Despite its high efficiency in TB treatment, delamanid poses delivery challenges due to poor water solubility leading to inadequate absorption upon oral administration. This study involves the development of novel formulation-based pressurized metered dose inhalers (pMDIs) containing self-microemulsifying mixtures of delamanid for efficient delivery to the lungs. To identify the appropriate self-microemulsifying formulations, ternary diagrams were plotted using different combinations of surfactant to co-surfactant ratios (1:1, 2:1, and 3:1). The combinations used Cremophor RH40, Poly Ethylene Glycol 400 (PEG 400), and peppermint oil, and those that showed the maximum microemulsion region and rapid and stable emulsification were selected for further characterization. The diluted self-microemulsifying mixtures underwent evaluation of dose uniformity, droplet size, zeta potential, and transmission electron microscopy. The selected formulations exhibited uniform delivery of the dose throughout the canister life, along with droplet sizes and zeta potentials that ranged from 24.74 to 88.99 nm and - 19.27 to - 10.00 mV, respectively. The aerosol performance of each self-microemulsifying drug delivery system (SMEDDS)-pMDI was assessed using the Next Generation Impactor, which indicated their capability to deliver the drug to the deeper areas of the lungs. In vitro cytotoxicity testing on A549 and NCI-H358 cells revealed no significant signs of toxicity up to a concentration of 1.56 µg/mL. The antimycobacterial activity of the formulations was evaluated against Mycobacterium bovis using flow cytometry analysis, which showed complete inhibition by day 5 with a minimum bactericidal concentration of 0.313 µg/mL. Moreover, the cellular uptake studies showed efficient delivery of the formulations inside macrophage cells, which indicated the potential for intracellular antimycobacterial activity. These findings demonstrated the potential of the Delamanid-SMEDDS-pMDI for efficient pulmonary delivery of delamanid to improve its effectiveness in the treatment of multi-drug resistant pulmonary TB.

Nanoemulsion potentiates the anti-cancer activity of Myricetin by effective inhibition of PI3K/AKT/mTOR pathway in triple-negative breast cancer cells

Triple-negative breast cancer (TNBC) is a heterogeneous tumor with a poor prognosis and high metastatic potential, resulting in poor clinical outcomes, necessitating investigation to devise effective therapeutic strategies. Multiple studies have substantiated the anti-cancer properties of the naturally occurring flavonoid "Myricetin" in various malignancies. However, the therapeutic application of Myricetin is impeded by its poor water solubility and low oral bioavailability. To overcome this limitation, we aimed to develop nanoemulsion of Myricetin (Myr-NE) and evaluate its advantage over Myricetin alone in TNBC cells. The nanoemulsion was formulated using Capryol 90 (oil), Tween 20 (surfactant), and Transcutol HP (co-surfactant). The optimized nano-formulation underwent an evaluation to determine its size, zeta potential, morphology, stability, drug encapsulation efficiency, and in vitro release properties. The anti-cancer activity of Myr-NE was further studied to examine its distinct impact on intracellular drug uptake, cell-viability, anti-tumor signaling, oxidative stress, clonogenicity, and cell death, compared with Myricetin alone in MDA-MB-231 (TNBC) cells. The in vitro drug release and intracellular drug uptake of Myricetin was significantly increased in Myr-NE formulation as compared to Myricetin alone. Moreover, Myr-NE exhibited significant inhibition of cell proliferation, clonogenicity, and increased apoptosis with ~ 2.5-fold lower IC50 as compared to Myricetin. Mechanistic investigation revealed that nanoemulsion augmented the anti-cancer efficacy of Myricetin, most likely by inhibiting the PI3K/AKT/mTOR pathway, eventually leading to enhanced cell death in TNBC cells. The study provides substantial experimental evidence to support the notion that the Myr-NE formulation has the potential to be an effective therapeutic drug for TNBC treatment.

In-vitro and in-vivo evaluation and anti-colitis activity of esculetin-loaded nanostructured lipid carrier decorated with DSPE-MPEG2000

OBJECTIVE

Encapsulation of esculetin into DSPE-MPEG2000 carrier was performed to improve its water solubility and oral bioavailability, as well as enhance its anti-inflammatory effect on a mouse model of ulcerative colitis that was induced with dextran sulphate sodium (DSS).

METHODS

We determined the in-vitro and in-vivo high-performance liquid chromatographic (HPLC) analysis method of esculetin; Esculetin-loaded nanostructure lipid carrier (Esc-NLC) was prepared using a thin-film dispersion method, wherein a particle size analyser was used to measure the particle size (PS) and zeta potential (ZP) of the Esc-NLC, while a transmission electron microscope (TEM) was employed to observe its morphology. Also, HPLC was used to measure its drug loading (DL), encapsulation efficiency (EE) and the in-vitro release of the preparation, as well as investigate the pharmacokinetic parameters. In addition, its anti-colitis effect was evaluated via histopathological examination of HE-stained sections and detection of the concentrations of tumour necrosis factor-alpha (TNF-α), interleukin (IL)-1 beta (β), and IL-6 in serum with ELISA kits.

RESULTS

The PS of Esc-NLC was 102.29 ± 0.63 nm with relative standard deviation (RSD) of 1.08% (with poly-dispersity index-PDI of 0.197 ± 0.023), while the ZP was -15.67 ± 1.39 mV with RSD of 1.24%. Solubility of esculetin was improved coupled with prolonged release time. Its pharmacokinetic parameters were compared with that of free esculetin, wherein the maximum concentration of the drug in plasma was increased by 5.5 times. Of note, bioavailability of the drug was increased by 1.7 times, while the half-life was prolonged by 2.4 times. In the anti-colitis efficacy experiment, the mice in Esc and Esc-NLC groups exhibited significantly reduced levels of TNF-α, IL-1β, and IL-6 in their sera comparable to the DSS group. Colon histopathological examination revealed that mice with ulcerative colitis in both Esc and Esc-NLC groups displayed improved inflammation, amid the Esc-NLC groups having the best prophylactic treatment effect.

CONCLUSION

Esc-NLC could ameliorate DSS-induced ulcerative colitis by improving bioavailability, prolonging drug release time and regulating cytokine release. This observation confirmed the potential of Esc-NLC to reduce inflammation in ulcerative colitis, albeit the need for follow-up research to verify the application of this strategy to clinical treatment of ulcerative colitis.

Development of Phytochemical Delivery Systems by Nano-Suspension and Nano-Emulsion Techniques

The awareness of the existence of plant bioactive compounds, namely, phytochemicals (PHYs), with health properties is progressively expanding. Therefore, their massive introduction in the normal diet and in food supplements and their use as natural therapeutics to treat several diseases are increasingly emphasized by several sectors. In particular, most PHYs possessing antifungal, antiviral, anti-inflammatory, antibacterial, antiulcer, anti-cholesterol, hypoglycemic, immunomodulatory, and antioxidant properties have been isolated from plants. Additionally, their secondary modification with new functionalities to further improve their intrinsic beneficial effects has been extensively investigated. Unfortunately, although the idea of exploiting PHYs as therapeutics is amazing, its realization is far from simple, and the possibility of employing them as efficient clinically administrable drugs is almost utopic. Most PHYs are insoluble in water, and, especially when introduced orally, they hardly manage to pass through physiological barriers and scarcely reach the site of action in therapeutic concentrations. Their degradation by enzymatic and microbial digestion, as well as their rapid metabolism and excretion, strongly limits their in vivo activity. To overcome these drawbacks, several nanotechnological approaches have been used, and many nanosized PHY-loaded delivery systems have been developed. This paper, by reporting various case studies, reviews the foremost nanosuspension- and nanoemulsion-based techniques developed for formulating the most relevant PHYs into more bioavailable nanoparticles (NPs) that are suitable or promising for clinical application, mainly by oral administration. In addition, the acute and chronic toxic effects due to exposure to NPs reported so far, the possible nanotoxicity that could result from their massive employment, and ongoing actions to improve knowledge in this field are discussed. The state of the art concerning the actual clinical application of both PHYs and the nanotechnologically engineered PHYs is also reviewed.

A Study on the Interactions of Proteinase K with Myricetin and Myricitrin by Multi-Spectroscopy and Molecular Modeling

Myricetin (MYR) and myricitrin (MYT) are well recognized for their nutraceutical value, such as antioxidant, hypoglycemic, and hypotensive effects. In this work, fluorescence spectroscopy and molecular modeling were adopted to investigate the conformational and stability changes of proteinase K (PK) in the presence of MYR and MYT. The experimental results showed that both MYR and MYT could quench fluorescence emission via a static quenching mechanism. Further investigation demonstrated that both hydrogen bonding and van der Waals forces play significant roles in the binding of complexes, which is consistent with the conclusions of molecular modeling. Synchronous fluorescence spectroscopy, Förster resonance energy transfer, and site-tagged competition experiments were performed to prove that the binding of MYR or MYT to PK could alter its micro-environment and conformation. Molecular docking results revealed that either MYR or MYT spontaneously interacted with PK at a single binding site via hydrogen bonding and hydrophobic interactions, which is consistent with the results of spectroscopic measurements. A 30 ns molecular dynamics simulation was conducted for both PK-MYR and PK-MYT complexes. The calculation results showed that no large structural distortions or interaction changes occurred during the entire simulation time span. The average RMSD changes of PK in PK-MYR and PK-MYT were 2.06 and 2.15 Å, respectively, indicating excellent stability of both complexes. The molecular simulation results suggested that both MYR and MYT could interact with PK spontaneously, which is in agreement with spectroscopic results. This agreement between experimental and theoretical results indicates that the method herein could be feasible and worthwhile for protein–ligand complex studies.

Recent Advances in Improving the Bioavailability of Hydrophobic/Lipophilic Drugs and Their Delivery via Self-Emulsifying Formulations

Formulations based on emulsions for enhancing hydrophobic and lipophilic drug delivery and its bioavailability have attracted a lot of interest. As potential therapeutic agents, they are integrated with inert oils, emulsions, surfactant solubility, liposomes, etc.; drug delivering systems that use emulsion formations have emerged as a unique and commercially achievable accession to override the issue of less oral bioavailability in connection with hydrophobic and lipophilic drugs. As an ideal isotropic oil mixture of surfactants and co-solvents, it self-emulsifies and forms fine oil in water emulsions when acquainted with aqueous material. As droplets rapidly pass through the stomach, fine oil promotes the vast spread of the drug all over the GI (gastrointestinal tract) and conquers the slow disintegration commonly seen in solid drug forms. The current status of advancement in technologies for drug carrying has promulgated the expansion of innovative drug carriers for the controlled release of self-emulsifying pellets, tablets, capsules, microspheres, etc., which got a boost for drug delivery usage with self-emulsification. The present review article includes various kinds of formulations based on the size of particles and excipients utilized in emulsion formation for drug delivery mechanisms and the increase in the bioavailability of lipophilic/hydrophobic drugs in the present time.

Flavonoids: Food associations, therapeutic mechanisms, metabolism and nanoformulations

Flavonoids possess an impressive therapeutic potential, thereby imparting them a nutraceutical character. As it becomes increasingly common to consume foods associated with healing properties, it is imperative to understand the associations of different foods with different classes of nutraceutic compounds, and their mechanisms of therapeutic action. At the same time, it is important to address the limitations thereof so that plausible future directions may be drawn. This review summarizes the food associations of flavonoids, and discusses the mechanisms responsible for imparting them their nutraceutic properties, detailing the nuclear factor erythroid 2-related factor 2 (NRF2) signaling pathway, inhibition of inflammatory signaling pathways such as toll-like receptor (TLR), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB), cyclooxygenase 2 (COX-2) and lipoxygenase-2 (LOX-2) mediators. Further on, the review explains the mechanism of flavonoids metabolism, reasons for low bioavailability and thereafter recapitulates the role of technological interventions to overcome the limitations, with a particular focus on nanoformulations that utilize the synergy between flavonoids and biocompatible materials used as nanocarriers, as reported in works spanning over a decade. It is the Generally Recognized as Safe (GRAS) classified carriers that will become the basis for developing functional formulations. It is promisingly noteworthy that some flavonoid formulations have been commercialized and mentioned therein. Such commercially viable and safe for consumption technological applications pave way for bringing science to the table, and add value to the innate properties of flavonoids.

Self-Emulsifying Systems for Delivery of Bioactive Compounds from Natural Origin

Nature has been used as therapeutic resources in the treatment of diseases for many years. However, some natural compounds have poor water solubility. Therefore, physicochemical strategies and technologies are necessary for development of systems for carrying these substances. The self-emulsifying drug delivery systems (SEDDS) have been used as carriers of hydrophobic compounds in order to increase the solubility and absorption, improving their bioavailability. SEDDS are constituted with a mixture of oils and surfactants which, when come into contact with an aqueous medium under mild agitation, can form emulsions. In the last years, a wide variety of self-emulsifying formulations containing bioactive compounds from natural origin has been developed. This review provides a comprehensive overview of the main excipients and natural bioactive compounds composing SEDDS. In addition, applications, new technologies and innovation are reviewed as well. Examples of self-emulsifying formulations administered in different sites are also considered for a better understanding of the use of this strategy to modify the delivery of compounds from natural origin.

Myricetin loaded nano-micelles delivery system reduces bone loss induced by ovariectomy in rats through inhibition of osteoclast formation

In recent years, much attention has been paid to the therapeutic effects of phytochemicals on osteoporosis. Other studies have shown that myricetin (MY) could promote osteogenic activity and inhibit osteoclastic effect, albeit little is known about effect of MY micellar system on osteoporosis. Therefore, we sought to discuss the therapeutic effect and mechanism of MY-loaded bone-targeting micelles on osteoporosis induced by ovariectomy (OVA) in rats. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles were prepared via ethanol injection method, while in vitro release study, bone targeting, pharmacokinetic studies, and the effect on proliferation of osteoblasts were investigated. Further, the therapeutic effect on osteoporosis was studied through ovariectomized rats. Compared with free MY, oral bioavailability of AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles in rats was increased by 3.54 times. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles exhibited bone targeting potential, and could significantly increase the activity of alkaline phosphatase and promote the proliferation of osteoblasts. Importantly, AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles mainly regulated bone metabolism by inhibiting bone resorption, thereby improving the symptoms of osteoporosis in OVA rats. The AL-P(LLA-CL)-PEG-P(LLA-CL)-MY micelles substantially enhanced the oral bioavailability of MY and demonstrated good bone targeting capability, thereby suggesting its prospect as carrier for osteoporotic improvement in OVA rats.

Preparation, characterization, pharmacokinetics, and antirenal injury activity studies of Licochalcone A-loaded liposomes

A liposome of Licochalcone A (LCA-Liposomes) was purposively prepared to ameliorate the low in vivo availability and efficacy of LCA. Physical characterization of LCA-Liposomes was carried out mainly by determining particle size, morphology, zeta potential (Z-potential), and efficiency of LCA encapsulation (EE) via appropriate techniques. Also, the rate of LCA release in vitro and distribution in vivo (plasma and tissues) was evaluated. Evaluation of the antirenal activity of LCA-liposomes was carried out by establishing chronic renal failure (CRF) model in mice through intragastric administration of adenine (200 mg/kg) and subsequent determination of biochemical parameters and examination of tissue sections. Respectively, the mean size of liposomal particles, Z-potential and EE of LCA-Liposomes were 71.78 ± 0.99 nm, -38.49 ± 0.06 mV, and 97.67 ± 1.72%. Pharmacokinetic and tissue distribution studies showed that LCA-Liposomes could improve the availability of LCA in the blood and tissues, whereas during pharmacodynamics studies, the liposome effectively improved the therapeutic effect of LCA on CRF mice by potentially protecting the renal tissues while exhibiting antioxidant activity. In conclusion, LCA-Liposomes could effectively improve the bioavailability of LCA and provide platform for the development of LCA-related functional products. PRACTICAL APPLICATIONS: As a traditional Chinese medicine, licorice is widely used in food and pharmaceutical industries. LCA is a small molecule flavonoid extracted from the root of licorice. In this study, LCA was loaded on liposome carriers, which significantly improved the water solubility and oral bioavailability, and proved that LCA-Liposomes have certain therapeutic effects on chronic renal failure, thereby providing a basis for the development of LCA into drugs or functional food in the future.

Lipid-based emulsion drug delivery systems - a comprehensive review

Lipid-based emulsion system - a subcategory of emulsion technology, has emerged as an enticing option to improve the solubility of the steadily rising water-insoluble candidates. Along with enhancing solubility, additional advantages such as improvement in permeability, protection against pre-systemic metabolism, ease of manufacturing, and easy to scale-up have made lipid-based emulsion technology very popular among academicians and manufacturers. The present article provides a comprehensive review regarding various critical properties of lipid-based emulsion systems, such as microemulsion, nanoemulsion, SMEDDS (self microemulsifying drug delivery system), and SNEDDS (self nanoemulsifying drug delivery system). The present article also explains in detail the similarities and differences between them, the stabilization mechanism, methods of preparation, excipients used to prepare them, and evaluation techniques. Subtle differences between nearly related terminologies such as microemulsion and nanoemulsion, SMEDDS, and SNEDDS are also explained in detail to clarify the basic differences. The present article also gives in-depth information regarding the chemical structure of various lipidic excipients, various possible chemical modifications to modify their inherent properties, and their regulatory status for rational selection.

Advances and challenges in nintedanib drug delivery

INTRODUCTION

Nintedanib (N.T.B) is an orally administered tyrosine kinase inhibitor that has been approved recently by U.S.F.D.A for idiopathic pulmonary fibrosis (I.P.F) and systemic sclerosis-associated interstitial lung disease (S.Sc-I.L.D). N.T.B is also prescribed in COVID-19 patients associated with I.P.F. However, it has an extremely low bioavailability of around 4.7%, and hence, researchers are attempting to address this drawback by different approaches.

AREAS COVERED

This review article focuses on enlisting all the formulation attempts explored by researchers to increase the bioavailability of N.T.B while also providing meaningful insight into the unexplored areas in formulation development, such as targeting of the lymphatic system and transdermal delivery. All the patents on the formulation development of N.T.B have also been summarized.

EXPERT OPINION

N.T.B has the potential to act on multiple diseases that are still being discovered, but its extremely low bioavailability is a challenge that is to be dealt with for obtaining the full benefit. Few studies have been performed aiming at improving the bioavailability, but there are unexplored areas that can be used, a few of which are explained in this article. However, the ability to reproduce laboratory results when scaling up to the industry level is the only factor to be taken into consideration.

Improvement of Oral Bioavailability and Anti-Tumor Effect of Zingerone Self-Microemulsion Drug Delivery System

This study sought to prepare a self-microemulsion drug delivery system containing zingerone (Z-SMEDDS) to improve the low oral bioavailability of zingerone and anti-tumor effect. Z-SMEDDS was characterized by particle size, zeta potential and encapsulation efficiency, while its pharmacokinetics and anti-tumor effects were also evaluated. Z-SMEDDS had stable physicochemical properties, including average particle size of 17.29 ± 0.07 nm, the zeta potential of -22.81 ± 0.29 mV, and the encapsulation efficiency of 97.96% ± 0.02%. In vitro release studies have shown the release of zingerone released by Z-SMEDDS was significantly higher than free zingerone in different release media. The relative oral bioavailability of Z-SMEDDS was 7.63 times compared with free drug. Meanwhile, the half inhibitory concentration （IC50）of Z-SMEDDS and free zingerone was 8.45 μg/mL and 13.30 μg/mL, respectively on HepG2. This study may provide a preliminary basis for further clinical research and application of Z-SMEDDS.

Improved Oral Bioavailability and Hypolipidemic Effect of Syringic Acid via a Self-microemulsifying Drug Delivery System

This study aimed to develop a self-microemulsifying drug delivery system (SMEDDS) to enhance the solubility, oral bioavailability, and hypolipidemic effects of syringic acid (SA), a bioactive and poorly-soluble polyphenol. Based on the response surface methodology-central composite design (RSM-CCD), an optimum formulation of SA-SMEDDS, consisting of ethyl oleate (oil, 12.30%), Cremophor-EL (surfactant, 66.25%), 1,2-propanediol (cosurfactant, 21.44%), and drug loading (50 mg/g), was obtained. The droplets of SA-SMEDDS were nanosized (16.38 ± 0.12 nm), spherically shaped, and homogeneously distributed (PDI = 0.058 ± 0.013) nanoparticles with high encapsulation efficiency (98.04 ± 1.39%) and stability. In vitro release study demonstrated a prolonged and controlled release of SA from SMEDDS. In vitro cell studies signified that SA-SMEDDS droplets substantially promoted cellular internalization. In comparison with the SA suspension, SA-SMEDDS showed significant prolonged T_max, t_1/2, and MRT after oral administration. Also, SA-SMEDDS exhibited a delayed in vivo elimination, increased bioavailability (2.1-fold), and enhanced liver accumulation. Furthermore, SA-SMEDDS demonstrated significant improvement in alleviating serum lipid profiles and hepatic steatosis in high-fat diet-induced hyperlipidemia in mice. Collectively, SMEDDS demonstrated potential as a nanosystem for the oral delivery of SA with enhanced bioavailability and hypolipidemic effects.

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.

Enhanced oral bioavailability of Bisdemethoxycurcumin-loaded self-microemulsifying drug delivery system: Formulation design, in vitro and in vivo evaluation

In this study, we sought to overcome the poor solubility and bioavailability of bismethoxycurcumin (BDMC) by fabricating a BDMC-loaded self micro-emulsifying system (BDMC-SMEDDS). Solubility and compatibility tests, pseudo-ternary phase diagrams (PTPDs) as well as d-optimal concept was applied to design the formulation. The assessment of the prepared BDMC-SMEDDS in-vitro mainly included droplet size (DS) and entrapment efficiency (EE) determination, morphology, drug release and stability testing. Besides, the in vivo behavior was also evaluated after oral administration of BDMC-SMEDDS to rats. The optimal formulation was found to compose of Kolliphor EL (K-EL, emulsifier, 645.3 mg), PEG 400 (co-emulsifier, 147.2 mg), ethyl oleate (EO, oil, 207.5 mg) and BDMC (50 mg). The BDMC-SMEDDS with satisfactory stability had a mean size of 21.25 ± 3.23 nm and EE of 98.31 ± 0.32%. Roughly 70% of BDMC was released from BDMC-SMEDDS within 84 h compared with <20% from the free BDMC. More importantly, the in-vivo behavior of BDMC-SMEDDS showed that the AUC_(0-12h) and plasma concentration of BDMC increased substantially as compared to the free BDMC. Altogether, BDMC-SMEDDS has the potential to enhance the solubility and bioavailability of BDMC and could be applied in the clinics.

Using Self-Nanoemulsifying System to Improve Oral Bioavailability of a Pediatric Antiepileptic Agent Stiripentol: Formulation and Pharmacokinetics Studies

This study aimed to develop a self-nanoemulsifying drug delivery system (SNEDDS) for poorly water-soluble drug stiripentol (STP) with enhanced oral bioavailability. Optimal excipients were selected by constructing pseudo-ternary phase diagrams using determined solubilities of STP, and then the proper composition of SNEDDS was investigated by employing a central composite design method. The optimized SNEDDS was composed of oil (ethyl oleate 39.61%), surfactant (Cremophor® RH 40 43.18%), co-surfactant (1,2-propanediol 17.21%), and STP of 50 mg/mL. The hydrodynamic size, zeta potential, and polydispersity index (PDI) were found to be 45.52 ± 1.99 nm, - 21.67 ± 0.24 mV, and 0.076 ± 0.011, respectively. The optimized STP-SNEDDS showed good stability in accelerated and dilution stability studies. It was also helpful to suppress STP degradation in acidic solution. Compared with STP suspension, STP-SNEDDS presented much faster dissolution rate. STP-SNEDDS successfully resulted in superior levels of C_max and AUC_{0 → 6 h} (4048.38 ± 704.54 μg/L and 7754.58 ± 1489.37 h μg/L, respectively) to STP suspension (1894.09 ± 1077.64 μg/L and 3556.93 ± 2470.01 h μg/L, respectively). The relative oral bioavailability of STP was 218.01%. The brain biodistribution studies showed that STP-SNEDDS presented significantly higher STP concentrations in the brain at 0.5 h and 1 h than that of STP suspension after administration. These findings indicated that a SNEDDS-based oral formulation of STP would be helpful for increasing its therapeutic potential.

Enhancement of loading and oral bioavailability of curcumin loaded self-microemulsifying lipid carriers using Curcuma oleoresins

The therapeutic applications of curcumin, a phenolic compound extracted from Curcuma species, is limited due to poor bioavailability. To enhance the bioavailability, self-microemulsifying drug delivery systems (SMEDDS) with curcumin were prepared. Ethyl oleate, Tween 80, and Transcutol^® P with surfactant: co-surfactant ratio of 2:1 w/w was selected based on the solubility and pseudo-ternary phase diagrams. The optimized formulation (S-Eo3) was evaluated for use of spice oleoresins as curcumin bioenhancers. The oleophilic phase of curcumin containing SMEDDS formulations was then successfully modified by using bioactive oleoresins extracted from two Curcuma species, viz. C. longa (S-CL1) and C. aromatica (S-CA1). The curcumin content in S-Eo3, S-CL1, and S-CA1 were 69.6 ± 0.23, 82.4 ± 0.62, and 88.8 ± 0.46 mg/g, respectively. Thus, by the partial modification of oleophilic phase of SMEDDS with spice oleoresin (acting as bioenhancer) resulted in ∼88 k improvement of curcumin aqueous solubility. The pharmacokinetic study in male Wistar rats showed that the relative bioavailability of curcumin in S-CL1 and S-CA1 were 26- and 29-fold vis-à-vis 22-fold in S-Eo3 compared to curcumin suspension. All the SMEDDS formulations were stable for three months as established by ICH guidelines.

Plant-Based Antidiabetic Nanoformulations: The Emerging Paradigm for Effective Therapy

Diabetes mellitus is a life-threatening metabolic syndrome. Over the past few decades, the incidence of diabetes has climbed exponentially. Several therapeutic approaches have been undertaken, but the occurrence and risk still remain unabated. Several plant-derived small molecules have been proposed to be effective against diabetes and associated vascular complications via acting on several therapeutic targets. In addition, the biocompatibility of these phytochemicals increasingly enhances the interest of exploiting them as therapeutic negotiators. However, poor pharmacokinetic and biopharmaceutical attributes of these phytochemicals largely restrict their clinical usefulness as therapeutic agents. Several pharmaceutical attempts have been undertaken to enhance their compliance and therapeutic efficacy. In this regard, the application of nanotechnology has been proven to be the best approach to improve the compliance and clinical efficacy by overturning the pharmacokinetic and biopharmaceutical obstacles associated with the plant-derived antidiabetic agents. This review gives a comprehensive and up-to-date overview of the nanoformulations of phytochemicals in the management of diabetes and associated complications. The effects of nanosizing on pharmacokinetic, biopharmaceutical and therapeutic profiles of plant-derived small molecules, such as curcumin, resveratrol, naringenin, quercetin, apigenin, baicalin, luteolin, rosmarinic acid, berberine, gymnemic acid, emodin, scutellarin, catechins, thymoquinone, ferulic acid, stevioside, and others have been discussed comprehensively in this review.

Self microemulsifying drug delivery system of lurasidone hydrochloride for enhanced oral bioavailability by lymphatic targeting: In vitro, Caco-2 cell line and in vivo evaluation

The global aim of this research was to develop and evaluate self-microemulsifying drug delivery system (SMEDDS) to improve oral bioavailability of Lurasidone Hydrochloride (LH). A chylomicron flow blocking approach was used to evaluate lymphatic drug transport. The developed LH-SMEDDS was composed of Capmul MCM C8 (oil), Cremophor EL (surfactant) and Transcutol HP (co-surfactant). Highest microemulsifying area was obtained at 3:1 ratio (surfactant:cosurfactant) and mean globule size was found to be 49.22 ± 1.60 nm. More than 98% drug release was obtained with LH-SMEDDS in phosphate buffer pH 6.8. Confocal microscopy and flow cytometry studies revealed higher fluorescence indicating deeper penetration across Caco-2 cells with Coumarin-6 SMEDDS as compared to Coumarin-6 solution. Mean Fluorescence Intensity (MFI) with Coumarin-6 loaded SMEDDS was increased 25.57 times with respect to Coumarin-6 solution. The permeability across Caco-2 cells was enhanced 3 times with LH-SMEDDS as compared to LH-suspension. Furthermore, Area Under Curve with LH-SMEDDS was found to be 2.92 times higher than that of LH suspension indicating improved bioavailability after formulating SMEDDS. Lymphatic transport in oral absorption of LH-SMEDDS was proved via lymphatic uptake study. All the findings suggest the effectiveness of lipid-based formulation i.e. SMEDDS of LH to augment the oral bioavailability via intestinal lymphatic pathway.