Nanoemulsion as a strategy for improving the oral bioavailability and anti-inflammatory activity of andrographolide

Enhancing Therapeutic Efficacy of Cinnamon Essential Oil by Nanoemulsification for Intravaginal Treatment of Candida Vaginitis

Background

Due to its prevalence, recurrence, and the emergence of drug-resistance, Candida vaginitis significantly impacts the well-being of women. Although cinnamon essential oil (CEO) possesses antifungal activity, its hydrophobic properties limit its clinical application.

Purpose

To overcome this challenge, a nanoemulsification technology was employed to prepare cinnamon essential oil-nanoemulsion (CEO@NE), and its therapeutic efficacy and action mechanism for Candida vaginitis was investigated in vivo and in vitro.

Materials and Methods

CEO@NE, composed of 4% CEO, 78% distilled water, and 18% Tween 80, was prepared by ultrasonic nanoemulsification. The physical properties, anti-Candida activity, cytotoxicity, immunomodulatory potential and storage stability of CEO@NE were explored. Subsequently, the effect of intravaginal CEO@NE treatment on Candida vaginitis was investigated in mice. To comprehend the possible mechanism of CEO@NE, an analysis was conducted to ascertain the production of intracellular reactive oxygen species (ROS) in C. albicans.

Results

CEO@NE, with the droplet size less than 100 nm and robust storage stability for up to 8 weeks, exhibited comparable anti-Candida activity with CEO. CEO@NE at the concentration lower than 400 μg/mL had no cytotoxic and immunomodulatory effects on murine splenocytes. Intravaginal treatment of CEO@NE (400 μg/mL, 20 μL/day/mouse for 5 consecutive days) curbed Candida colonization, ameliorated histopathological changes, and suppressed inflammatory cytokine production in mice intravaginally challenged with C. albicans. Notably, this treatment preserved the density of vaginal lactic acid bacteria (LAB) crucial for vaginal health. Co-culturing C. albicans with CEO@NE revealed concentration-dependent augmentation of intracellular ROS generation and ensuing cell death. In addition, co-culturing LPS-stimulated murine splenocytes with CEO@NE yielded a decrease in the generation of cytokines.

Conclusion

This discovery provides insight into the conceivable antifungal and anti-inflammatory mechanisms of CEO@NE to tackle Candida vaginitis. CEO@NE offers a promising avenue to address the limitations of current treatments, providing novel strategy for treating Candida vaginitis.

Pharmacokinetics behavior of four cannabidiol preparations following single oral administration in dogs

Cannabidiol (CBD) is a natural phytochemical agent and one of the most abundant found in Cannabis sativa. It is known to exhibit pharmacological properties on various condition such as relieving-inflammation, pain, epilepsy, and anxiety effect. There has been an increasing trend globally in the use of CBD as a supplement in pets. Consequently, there are various CBD products being marketed that are specifically available for pets. Veterinarians and pet owners are concerned that following ingestion, different CBD formulations may result in a CBD level circulating in the blood that may affect the safe use and efficacy of CBD in pets. Several pharmacokinetics studies in animals have been mainly conducted with an oily form of CBD. To date, there is a lack of data regarding direct comparisons in animals among the CBD plasma kinetic profiles from an oral administration of the various preparation forms. Therefore, the current study evaluated and compared the plasma CBD levels from a single oral administration using four different CBD preparations-liquid (an oil-based form, a nanoemulsion form, or a water-soluble form) or a semi-solid form (as CBD mixed in a treat) in dogs. In total, 32 healthy, crossbreed dogs were randomly assigned into 4 groups and treated according to a 1-period, 4-treatment parallel-design. The three liquid forms were dosed at 5 mg/kg body weight, while the single semi-solid form was given at 50 mg/treat/dog. The results showed that the CBD plasma profile from the administration of a water-soluble form was comparable to that of the oil-based group. The nanoemulsion-based form tended to be rapidly absorbed and reached its peak sooner than the others. However, the CBD in all preparations reached the maximum plasma concentration within 3 h post-dose, with an average range of 92-314 μg/L. There were significant differences among certain parameters between the liquid and semi-solid forms. This was the first study to provide pharmacokinetics data regarding CBD in water soluble, nanoemulsion-based, and semi-solid forms for dogs as companion animals. The current data should facilitate the scrutiny of CBD plasma profiles based on different formulations via an oral route in dogs.

Synthesis and Characterization of Carbon-Based Quantum Dots and Doped Derivatives for Improved Andrographolide's Hydrophilicity in Drug Delivery Platforms

Carbon-based quantum dots (CBQDs), sulfur-doped carbon-based quantum dots (S-CBQDs), and nitrogen-doped carbon-based quantum dots (N-CBQDs) have strong potential for drug delivery platforms. They were conjugated with andrographolide, a well-known hydrophobic drug, to study the concomitant changes in hydrophilicity. The interactions between these nanomaterials and the drug were studied by characterizing the optical and structural properties of the nanoparticles before and after coupling with the drug. It was found that the interaction of the drug with these nanomaterials produced noticeable changes in their optical and structural properties. Moreover, the partition coefficient for the nanocomposites was determined by NMR. The results indicate that conjugating the drug with the nanoparticles significantly enhanced its affinity for the aqueous phase, from 2.632 to 0.1117, thereby opening the possibility of using this approach for developing an effective drug delivery platform for this hydrophobic drug.

Influence of Poloxamer 188 on Anti-Inflammatory and Analgesic Effects of Diclofenac-Loaded Nanoemulsion: Formulation, Optimization and in Vitro/in Vivo Evaluation

In this study, a polymer-stabilized nanoemulsion (PNE) was developed to improve the inflammatory and analgesic activities of diclofenac (DA). DA-PNEs were prepared from sesame oil and poloxamer 188 (P188), polysorbate 80, and span 80 as emulsifiers and optimized by a systematic multi-objective optimization method. The developed DA-PNEs exhibited thermodynamical stability with low viscosity. The mean diameter, PDI, surface charge, and entrapment efficiency of DA-PNEs were 122.49±3.42 nm, 0.226±0.08, -47.3 ± 3.6 mV, and 93.57±3.4 %, respectively. The cumulative in vitro release profile of DA-PNEs was significantly higher than the neat drug in simulated gastrointestinal fluids. The anti-inflammatory activities of DA-PNEs were evaluated in the λ-carrageenan-induced paw edema model. To investigate the effect of P188 on analgesic and anti-inflammatory activities, a formulation without P188 was also prepared and named DA-NEs. Following oral administration, DA-PNEs showed a significantly higher (p<0.05) effect in reducing pain and inflammation symptoms as compared to free diclofenac and DA-NEs. Moreover, histopathological examination confirmed that DA-PNEs meaningfully reduced the extent of paw edema, comparable to that of DA. Taken together, the findings of the in vitro and in vivo studies suggest that diclofenac-loaded P188-stabilized nanoemulsion can be considered a potential drug delivery system for treating and controlling inflammatory disorders and alleviating pains.

Oral administration of Huanglian-Houpo herbal nanoemulsion loading multiple phytochemicals for ulcerative colitis therapy in mice

How to achieve stable co-delivery of multiple phytochemicals is a common problem. This study focuses on the development, optimization and characterization of Huanglian-HouPo extract nanoemulsion (HLHPEN), with multiple components co-delivery, to enhance the anti-ulcerative colitis (UC) effects. The formulation of HLHPEN was optimized by pseudo-ternary phase diagram combined with Box-Behnken design. The physicochemical properties of HLHPEN were characterized, and its anti-UC activity was evaluated in DSS-induced UC mice model. Based on preparation process optimization, the herbal nanoemulsion HLHPEN was obtained, with the droplet size, PDI value, encapsulation efficiency (EE) for 6 phytochemicals (berberine, epiberberine, coptisine, bamatine, magnolol and honokiol) of 65.21 ± 0.82 nm, 0.182 ± 0.016, and 90.71 ± 0.21%, respectively. The TEM morphology of HLHPEN shows the nearly spheroidal shape of particles. The optimized HLHPEN showed a brownish yellow milky single-phase and optimal physical stability at 25 °C for 90 days. HLHPEN exhibited the good particle stability and gradual release of phytochemicals in SGF and SIF, to resist the destruction of simulated stomach and small intestine environment. Importantly, the oral administration of HLHPEN significantly restored the shrunk colon tissue length and reduced body weight, ameliorated DAI value and colon histological pathology, decreased the levels of inflammatory factors in DSS-induced UC mice model. These results demonstrated that HLHPEN had a significant therapeutic effect on DSS-induced UC mice, as a potential alternative UC therapeutic agent.

Recent Advances in Nanoformulations for Quercetin Delivery

Quercetin (QUE) is a flavonol that has recently received great attention from the research community due to its important pharmacological properties. However, QUE's low solubility and extended first-pass metabolism limit its oral administration. This review aims to present the potential of various nanoformulations in the development of QUE dosage forms for bioavailability enhancement. Advanced drug delivery nanosystems can be used for more efficient encapsulation, targeting, and controlled release of QUE. An overview of the primary nanosystem categories, formulation processes, and characterization techniques are described. In particular, lipid-based nanocarriers, such as liposomes, nanostructured-lipid carries, and solid-lipid nanoparticles, are widely used to improve QUE's oral absorption and targeting, increase its antioxidant activity, and ensure sustained release. Moreover, polymer-based nanocarriers exhibit unique properties for the improvement of the Absorption, Distribution, Metabolism, Excretion, and Toxicology (ADME(T)) profile. Namely, micelles and hydrogels composed of natural or synthetic polymers have been applied in QUE formulations. Furthermore, cyclodextrin, niosomes, and nanoemulsions are proposed as formulation alternatives for administration via different routes. This comprehensive review provides insight into the role of advanced drug delivery nanosystems for the formulation and delivery of QUE.

Liquid Chromatography-Electrospray Ionization Tandem Mass Spectrometry Estimation of Quercetin-Loaded Nanoemulsion in Rabbit Plasma: In Vivo-In Silico Pharmacokinetic Analysis Using GastroPlus

In the present study, we developed and validated a rapid, specific, sensitive, and reproducible liquid chromatography-electrospray ionization tandem mass spectrometry method for quantifying quercetin (QT) in rabbit plasma using hydrochlorothiazide as the internal standard. Animals were orally administered with optimized QT-loaded nanoemulsion (QTNE) and QT suspension (QTS), equivalent to 30 mg/kg, to the test and control group, respectively. The blood samples were collected at pre-determined time points up to 48 h. The linearity range was from 5 to 5000 ng mL^-1 with R ² = 0.995. Further, we analyzed the various pharmacokinetic parameters and established the in vitro-in vivo correlation (IVIVC) of QTNE using GastroPlus software. The method was successfully developed and validated, and when applied for the determination of QT in rabbit plasma, it exhibited an increase in C _max from 122.56 ng mL^-1 (QTS) to 286.51 ng mL^-1 (QTNE) (2.34-fold) and AUC_0-48 from 976 ng h mL^-1 (QTS) to 4249 ng h mL^-1 (QTNE) (4.35-fold), indicating improved oral bioavailability QT when administered as QTNE. Statistical analysis revealed that the Loo-Riegelman method (two-compartmental method) best fitted the deconvolution approach (R ² = 0.998, SEP = 4.537, MAE = 2.759, and AIC = 42.38) for establishing the IVIVC. In conclusion, the established bioanalytical method and IVIVC studies revealed that QTNE is a potential carrier for the effective delivery of QT with enhanced oral bioavailability.

Curcumin nanoemulsion counteracts hepatic and cardiac complications associated with high-fat/high-fructose diet in rats

The relationship between the incidence of cardiovascular abnormalities and non-alcoholic fatty liver disease (NAFLD) has long been postulated. Curcumin (CUR) is a potential anti-atherosclerotic agent but its poor water solubility hinders its pharmacological use. Therefore, the present study aimed to investigate the effect of formulation of CUR nanoemulsion prepared using the spontaneous emulsification technique on high fat high fructose (HFHF)-induced hepatic and cardiac complications. Fifty Wistar rats were divided into five groups. CUR nanoemulsion at doses of 5 and 10 mg/kg and conventional powdered CUR at a dose of 50 mg/kg were orally administered daily to rats for two weeks, and compared with normal control and HFHF control. Results revealed that the high dose level of CUR nanoemulsion was superior to conventional CUR in ameliorating the HFHF-induced insulin resistance status and hyperlipidemia, with beneficial impact on rats' recorded electrocardiogram (ECG), serum aspartate aminotransferase (ALT) and alanine aminotransferase (AST) levels, leptin, adiponectin, creatine phosphokinase, lactate dehydrogenase and cardiac troponin-I. In addition, hepatic and cardiac oxidative and nitrosative stresses, oxidative DNA damage and disrupted cellular energy statuses were counteracted. Results were also confirmed by histopathological examination. PRACTICAL APPLICATIONS: The use of curcumin nanoemulsion could be beneficial in combating hepatic and cardiac complications resulting from HFHF diets.

Boosting Tadalafil Bioavailability via Sono-Assisted Nano-Emulsion-Based Oral Jellies: Box-Behnken Optimization and Assessment

Tadalafil (TAD) is a poorly soluble, phosphodiesterase inhibitor used to treat erectile dysfunction. The primary goal of this project was to prepare nano-emulsions using ultrasonic technology to address TAD bioavailability concerns. The Box−Behnken design was employed to find prominent correlations between factors impacting the sono-emulsification process. The emulsifier concentration, amplitude level, and ultrasonication time were the independent factors, whereas the average droplet size (ADS) and polydispersity index (PDI) were designated as the response variables. TAD-loaded nano-emulsions (93−289 nm) were generated and the emulsifier concentration showed a crucial role in directing emulsion droplet size. The model desirability function was utilized to optimize a nano-emulsion with a small ADS (99.67 ± 7.55 nm) and PDI (0.45 ± 0.04) by adjusting the emulsifiers concentration, amplitude level, and ultrasonication time at 9.85%, 33%, 49 s, respectively. The optimized nano-emulsions did not demonstrate any precipitation or phase separation after stability stress tests. TAD jellies were formulated based on the optimized nano-emulsion and subjected to in vitro evaluation for physical characteristics; TAD content, pH, spreadability, viscosity, syneresis, and taste-masking ability. An optimized nano-emulsion-based jelly (NEJ) formulation showed more than 96% drug dissolution in 30 min relative to 14% for the unprocessed TAD. In vivo assessment of NEJ in experimental rats demonstrated a significant enhancement (p < 0.05) of TAD bioavailability with an AUC0−24h of 2045 ± 70.2 vs. 259.9 ± 17.7 ng·h·mL−1 for the unprocessed TAD. Storage stability results revealed that NEJ remained stable with unremarkable changes in properties for 3 months. Overall, NEJ can be regarded as a successful therapeutic option for TAD administration with immediate-release properties and improved bioavailability.

Self-Emulsifying Phospholipid Preconcentrates for the Enhanced Photoprotection of Luteolin

Exposure to ultraviolet B (UVB) leads to the overproduction of reactive oxygen species (ROS), causing higher risks of skin disorders. Luteolin (Lut) is a naturally occurring antioxidant that can absorb a broad range of ultraviolet light, but its water solubility and skin permeability are limited and insufficient. The aim of the current study was to develop a Lut-loaded self-emulsifying phospholipid preconcentrate (LSEPP) for enhancing the solubility, permeability, and photoprotective activity of Lut. The designed formulations were firstly examined for their droplet size, zeta potential, dispersity, and in vitro corneum permeability after dispensing the preconcentrate to form an emulsion; the optimized formulation was further characterized for its emulsified morphology, compatibility with excipients, stability in the preconcentrate form, and photoprotective activity by the HaCaT cell model under the emulsified status. The optimized LSEPP formulation attained a smaller droplet size (140.6 ± 24.2 nm) with the addition of 1,8-cineole and increased the permeability of Lut by 7-fold. As evidenced in the cell model studies, the optimized LSEPP formulation can efficiently deliver Lut into HaCaT cells after emulsification and result in a 115% better cell viability as well as a 203% stronger ROS scavenging capability, compared with those of unformulated Lut after UVB irradiation. To sum up, we have successfully developed an LSEPP formulation, which is a safe and promising topical delivery system for enhancing the photoprotective effects of Lut.

Tea Tree Oil Nanoemulsion-Based Hydrogel Vehicle for Enhancing Topical Delivery of Neomycin

The present investigation aims to improve the antimicrobial influence of certain antibacterial drugs, namely, neomycin (NEO), exploiting the benefits of natural oils such as tea tree oil (TTO). Therefore, a distinctive nanolipid formulation, namely, a nanoemulsion (NE), was developed using a Central Composite Factorial Design (CCD) approach depending on the amount of TTO and tween 80 as surfactant. The optimized NEO-NE formula exhibiting minimum globular size and maximum in vitro release was selected. For efficient topical delivery, NEO-NE was incorporated into a pre-formulated hydrogel. The developed NEO-NE-hydrogel was characterized by its physical characteristics such as pH, viscosity, and spreadability. Next, it was tested for stability under different conditions for 3 months. Ultimately, an irritation test was conducted followed by an antibacterial examination. The preparation demonstrated acceptable properties to be successfully applied topically. It showed non-significant changes in stability in both conditions up to 3 months storage when compared to a fresh preparation. It exhibited no irritation when applied on hairless animal skin. Finally, TTO revealed a good inhibition for the bacterial growth that could improve the influence of NEO antibacterial activity, indicating the efficiency of NE containing NEO prepared with TTO to be a promising antibacterial nanocarrier.

Andrographolide induces anti-SARS-CoV-2 response through host-directed mechanism: an in silico study

Aim: Considering the present alarming situation of COVID-19 pandemic, we concentrated on evaluating the efficacy of a novel natural antiviral drug-candidate andrographolide against SARS-CoV-2 through an in silico model of study. Materials & methods: Interaction of andrographolide against the major host molecules that are responsible for SARS-CoV-2 pathogenesis were determined using bio-computational tools, in other words, molecular docking, molecular dynamics simulation and pharmacodynamics–pharmacokinetics analysis. Result: Computational findings represent that andrographolide efficiently interacts with the major human–host-associated putative drug-targets of viral-entry points like furin (-10.54 kcal/mol), TMPRSS-2 (-9.50 kcal/mol), ACE2 (-8.99 kcal/mol) and Cathepsin L (-8.98 kcal/mol). Moreover, it also blocks the inflammatory regulators including TLR4-MD2 and IL-6, which promote virus-induced inflammation leading to cytokine storm in the host body. Conclusion: This work elucidates that, the candidature of andrographolide can be utilized as a potent natural agent for the therapeutic intervention of SARS-CoV-2 through host-directed treatment.

Andrographolide in Atherosclerosis: Integrating Network Pharmacology and In Vitro Pharmacological Evaluation

Objective: Andrographis paniculata (Burm.f.) Nees is a medicinal plant that has been traditionally used as an anti-inflammatory and antibacterial remedy for several conditions. Andrographolide (AG), the active constituent of A. paniculata (Burm.f.) Nees, has anti-lipidic and anti-inflammatory properties as well as cardiovascular protective effects. The present study aimed to explore the effects of AG on the progression of atherosclerosis and to investigate related mechanisms via network pharmacology.

Materials and methods: Compound-related information was obtained from the PubChem database. Potential target genes were identified using STITCH, SwissTargetPrediction, Bioinformatics Analysis Tool for Molecular mechANism of Traditional Chinese Medicine, and Comparative Toxicogenomics Database. Genes involved in atherosclerosis were obtained from DisGeNet and compared with AG target genes to obtain an overlapping set. Protein–protein interactions were determined by STRING. Gene ontology (GO) analysis was performed at WebGestalt, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment was analyzed using Metascape. The final network showing the relationship between compounds, targets, and pathways was constructed using Cytoscape. After that, oxLDL-induced RAW264.7 cells were used to further validate a part of the network pharmacology results.

Result: Eighty-one potential AG target genes were identified. PPI, GO, and KEGG enrichment revealed genes closely related to tumor progression, lipid transport, inflammation, and related pathways. AG improves the reverse cholesterol transport (RCT) through NF-κB/CEBPB/PPARG signaling in oxLDL-induced RAW264.7 cells.

Conclusion: We successfully predict AG’s potential targets and pathways in atherosclerosis and illustrate the mechanism of action. AG may regulate NF-κB/CEBPB/PPARG signaling to alleviate atherosclerosis.

Poly (Lactic-Co-Glycolic) Acid–Poly (Vinyl Pyrrolidone) Hybrid Nanoparticles to Improve the Efficiency of Oral Delivery of β-Carotene

The aim of this study was to develop a nanoparticle formulation made of poly (vinyl pyrrolidone) (PVP) and poly (lactic-co-glycolic) acid (PLGA) for the oral delivery of β-carotene (BC). The hybrid nanoparticles were prepared by the interfacial deposition method, and the physicochemical properties of this formulation were characterized in terms of its morphology, particle size, size distribution, encapsulation efficiency, dissolution, intestinal permeability, and in vivo pharmacokinetics. Our results demonstrated that BC-loaded nanoformulation and PLGA nanoparticles (PNP) significantly enhanced a release 6.1 times higher than BC suspension. The fortification of PVP into PLGA nanoparticles, named PLGA–PVP hybrid nanoparticles (PPNP), significantly reduced the particle size, as well as led to an increase 1.9 times higher in the in vitro release of BC, compared with PNP. For the ex vivo intestinal permeability assessment, PNP and PPNP–K15 significantly enhanced the intestinal permeability by 2.7 and 6.5 times at the jejunum, and 2.3 and 4.5 times at the ileum, when compared with unformulated BC. According to the pharmacokinetic study, the optimized hybrid formulation significantly increased the peak plasma concentration (C_max) and the area under the curve (AUC_0-t), and the oral relative bioavailability showed a five-fold enhancement compared with that of the BC suspension. Our results indicate that the hybrid nanoparticulate delivery system is an efficient strategy for the oral delivery of BC.

A comparative study between curcumin and curcumin nanoemulsion on high-fat, high-fructose diet-induced impaired spermatogenesis in rats

Objectives

Curcumin is a promising nutraceutical with reported diverse therapeutic properties, but of limited oral bioavailability. The current manuscript investigates the role of encapsulation of curcumin in nanoemulsion form in counteracting the adverse effect of chronic ingestion of a high-fat high-fructose diet (HFHF) by juvenile male rats regarding testicular abnormalities and declined spermatogenesis.

Methods

Curcumin nanoemulsion was administered orally to Wistar rats at a dose of 5 or 10 mg/kg and compared with curcumin powder, followed by a pharmacological and histological assessment.

Key findings

Results demonstrated that curcumin nanoemulsion was superior to curcumin powder, particularly in enhancing the percentage progressive motility of spermatozoa, normalization of essential and non-essential amino acids in semen, normalization of serum leptin and testosterone levels, as well as normalization of oxidative and nitrosative parameters. It was also proven to reduce testicular DNA fragmentation, while elevating testicular cellular energy. In addition, curcumin nanoemulsion administered at a dose of 10 mg/kg induced the highest level of spermatogenesis, delineated by histological examination of the seminiferous tubules.

Conclusions

It can be concluded that curcumin nanoemulsion administered at a dose of 10 mg/kg successfully ameliorates the adverse effects of a HFHF on spermatogenesis.

Assessment of Pharmacokinetic Parameters of Daidzein-Containing Nanosuspension and Nanoemulsion Formulations After Oral Administration to Rats

BACKGROUND AND OBJECTIVES

Daidzein has several biological effects such as antioxidation, anti-inflammation, chemoprevention, and anticancer effects. The aim of this study was to evaluate the impact of nano-formulations (nanoemulsion-NE and nanosuspension-NS) prepared to increase the oral bioavailability of daidzein, a poorly water-soluble isoflavone, on the pharmacokinetic parameters of daidzein in rats.

METHODS

A high-performance liquid chromatography-ultraviolet (HPLC-UV) method was successfully developed for daidzein analysis in rat plasma. The pharmacokinetics studies of the nano-sized formulations, compared to coarse daidzein suspension, were carried out in the rats by a single oral dose at 10 mg/kg (n = 6/group). Area under the plasma concentration-time curve from time zero to extrapolation to time infinity (AUC_0-∞), maximum plasma concentration (C_max), time to reach maximum plasma concentration (t_max), and elimination half life (t_1/2) values for coarse daidzein suspension, daidzein-NS, and daidzein-NE were estimated by a non-compartmental analysis.

RESULTS

The AUC values of daidzein-NE and daidzein-NS were approximately 2.62 and 2.65 times higher than that of coarse daidzein suspension, respectively (p < 0.05). Relative bioavailability (F_rel) (%) values of daidzein following oral administration of nanosuspension or nanoemulsion formulations were about 265.6% and 262.3%, respectively.

CONCLUSION

It revealed that nanoscale size is an important factor to overcome any dissolution rate barriers to oral bioavailability of the low water-soluble compound. Nanoemulsion and nanosuspension formulations are beneficial dosage forms to increase the oral bioavailability of Biopharmaceutical Classification System (BCS) Class II and Class IV compounds.

An insight into the pharmacological and analytical potential of Andrographolide

Andrographis paniculata is an annual medicinal herb from the family Acanthaceae. Andrographolide is generally considered an essential bioactive component of plant A. paniculata. Since ancient times, it has been widely recognized for its therapeutic qualities and has attracted the scientific and medical communities' attention. This review summarizes the molecular, clinical, and in vitro research of compound andrographolide and its mechanism of action. Andrographolide, when combined with other enhancing agents, offers a wide variety of health benefits. The therapeutic potential of andrographolide has been exemplified and exhibited by directly regulating genes and indirectly interacting with small molecules and different enzymes. This review compiles and consolidates the pharmacological action of andrographolide and its analogs and deciphers the gaps that have hindered its use in medicinal research.

Development of Chitosan-Based Nanoemulsion Gel Containing Microbial Secondary Metabolite with Effective Antifungal Activity: In vitro and in vivo Characterizations

Purpose

Microbial resistance to antibiotics is one of the most important public health concerns of the 21^st century. We isolated, purified, and structurally elucidated antifungal secondary metabolites from red soil microbes and encapsulated them into chitosan (CS)-based nanoemulsion (NE) gel (NEG).

Methods

Three compounds were isolated and purified of which only one compound (Pure 2) showed potent antifungal activity (MFC: 8–132 µg/mL), which was also significantly (P<0.05) more efficient than fluconazole (MFC: 32–132 µg/mL). Pure 2 was structurally elucidated using 1D- and 2D-NMR before its incorporation into NEG. The formulations were prepared by high-speed homogenization technique. Physicochemical and pharmacological characterizations of formulations (ie, droplet size, PDI, zeta potential, drug content, viscosity, SEM, FTIR, spreadability, in vitro drug release, ex vivo permeation, in vitro antifungal and in vivo antifungal activities) were assessed.

Results

NMR analyses identified the compound as a derivative of phthalic acid ester (PAE). The optimized formulations displayed a droplet size <100 nm, -ve zeta potential, and PDI <0.45. The drug content was within the official limit of pharmacopeia (ie, 100±10%). Insignificant changes (P>0.05) in the viscosity of the formulations stored were observed. The morphology of the formulations indicated mesh-like structure. The FTIR study indicated that there were no interactions between the drug and other ingredients of the formulations. Optimum spreadability was observed in all formulations. NEG released 75.3±1.12% of Pure 2 after 12 hrs while NE released 85.33±1.88% of the compound. The skin permeation of F2 (71.15±1.28%) was significantly different (P<0.05) from F3 (81.80±1.91%) in rabbits. Complete and apparently safe recovery from the fungal infection was achieved in rabbits treated topically with Pure 2-loaded NEGs.

Conclusion

Hence, the NEG-loaded PAE isolated from Pseudomonas fluorescens represents a possible alternative for the treatment of fungal infections as compared to available therapies.

Andrographolide: A review of its pharmacology, pharmacokinetics, toxicity and clinical trials and pharmaceutical researches

Andrographis paniculata (Burm. f.) Wall. ex Nees, a renowned herb medicine in China, is broadly utilized in traditional Chinese medicine (TCM) for the treatment of cold and fever, sore throat, sore tongue, snake bite with its excellent functions of clearing heat and toxin, cooling blood and detumescence from times immemorial. Modern pharmacological research corroborates that andrographolide, the major ingredient in this traditional herb, is the fundamental material basis for its efficacy. As the main component of Andrographis paniculata (Burm. f.) Wall. ex Nees, andrographolide reveals numerous therapeutic actions, such as antiinflammatory, antioxidant, anticancer, antimicrobial, antihyperglycemic and so on. However, there are scarcely systematic summaries on the specific mechanism of disease treatment and pharmacokinetics. Moreover, it is also found that it possesses easily ignored security issues in clinical application, such as nephrotoxicity and reproductive toxicity. Thereby it should be kept a lookout over in clinical. Besides, the relationship between the efficacy and security issues of andrographolide should be investigated and evaluated scientifically. In this review, special emphasis is given to andrographolide, a multifunctional natural terpenoids, including its pharmacology, pharmacokinetics, toxicity and pharmaceutical researches. A brief overview of its clinical trials is also presented. This review intends to systematically and comprehensively summarize the current researches of andrographolide, which is of great significance for the development of andrographolide clinical products. Noteworthy, those un-cracked issues such as specific pharmacological mechanisms, security issues, as well as the bottleneck in clinical transformation, which detailed exploration and excavation are still not to be ignored before achieving integration into clinical practice. In addition, given that current extensive clinical data do not have sufficient rigor and documented details, more high-quality investigations in this field are needed to validate the efficacy and/or safety of many herbal products.

Andrographis paniculata Formulations: Impact on Diterpene Lactone Oral Bioavailability

Diterpene lactones have been identified as active compounds in several medicinal plants, including Andrographis paniculata (Burm. f.) Nees, which is a medicinal plant that has been used for centuries across the world. Andrographolide is the major diterpene from A. paniculata and the main bioactive constituent of this species. The effectiveness of diterpenes can be affected by factors that limit their oral bioavailability, such as their poor water solubility, slow dissolution rates, low gastrointestinal absorption, high chemical and metabolic instability, and rapid excretion. In this context, the purpose of the present review is to compile and compare literature data on the bioavailability of diterpene lactones from A. paniculata after oral administration in medicinal plant extracts or in their free forms and to highlight strategies that have been used to improve their oral bioavailability. Considering that medicinal plant extracts are commonly used as dried powder that is reconstituted in water before oral administration, novel pharmaceutical formulation strategies that are used to overcome difficulties with diterpene solubility are also compiled in this review. The use of self-microemulsifying drug delivery systems is a good strategy to enhance the dissolution and consequently the bioavailability of andrographolide after oral administration of A. paniculata extract formulations. On the other hand, herbosome technology, pH-sensitive nanoparticles, nanosuspensions, nanoemulsions, nanocrystal suspensions, nanocrystal-based solid dispersions, and solid dispersion systems are useful to formulate andrographolide in its free form and increase its oral bioavailability. The use of a suitable andrographolide delivery system is essential to achieve its therapeutic potential.

Fabrication and Characterization of Polymeric Pharmaceutical Emulgel Co-Loaded with Eugenol and Linalool for the Treatment of Trichophyton rubrum Infections

Trichophyton rubrum (T. rubrum) is the main cause of chronic dermatophytosis which is highly prevalent worldwide. This study was aimed to fabricate and characterize polymeric emulgel of eugenol and linalool for the treatment of T. rubrum infections. Using the slow emulsification method, the emulgel was prepared and characterized for thermodynamic stability, pH analysis, viscosity, spreadability, swelling behavior, %drug content, surface morphology, globules size, polydispersity index, surface charge (mV), thermal behavior, in vitro drug release and XRD studies. Biological activities of emulgel were conducted against T. rubrum in vitro and in vivo. Results indicated that emulgel formulations were thermodynamically stable. The pH of the formulations was within an acceptable range for skin. The viscosity and spreadability were optimum for the better patient compliance. The swelling behavior was 111.10 ± 1.25% after 90 min. The drug content was within the official pharmacopeia limit i.e., 100 ± 10%. The surface morphology revealed by scanning electron microscopy showed a spherical-shaped structure with characteristic larger cracks and wrinkles. The droplet size, PDI, and surface charge of the optimized emulgel were 888.45 ± 8.78 nm, 0.44 and -20.30 mV, respectively. The emulgel released 84.32% of eugenol and 76.93% of linalool after 12 h. There was complete disappearance of the diffraction peaks corresponding to the drugs after XRD analysis. In rabbits, the infection was safely and completely recovered after 12 days and the emulgel produced significant effects (p < 0.05) similar to the standard product Clotrim^®. It is concluded that the eugenol-linalool emulgel best described all its physical properties and can be applied topically for the treatment of T. rubrum infections.

Nanoemulsions as Ophthalmic Drug Delivery Systems

Nanoemulsions are liquid-in-liquid dispersion with a droplet size of about 100 nm. They have a transparent appearance, high rate of bioavailability, and increased shelf life. Nanoemulsions mainly consist of oil, water, surfactant, and cosurfactant and can be prepared by high- and low-energy methods. Diluted nanoemulsions are utilized for the delivery of ophthalmic drugs due to their capability to penetrate the deep layers of the ocular structure, provide a sustained release effect, and reduce the frequency of administration and side effects. These nanoemulsions are subjected to certain tests, such as safety, stability, pH profile, rheological studies, and so on. Cationic nanoemulsions are prepared for topical ophthalmic delivery of active ingredients from cationic agents to increase the drug residence time on the ocular surface, reducing their clearance from the ocular surface and improving drug bioavailability. This review article summarizes the main characteristics of nanoemulsions, ophthalmic nanoemulsions, and cationic nanoemulsions and their components, methods of preparation, and the evaluation parameters for ophthalmic nanoemulsions.

Hypericin-loaded oil-in-water nanoemulsion synthesized by ultrasonication process enhances photodynamic therapy efficiency

Hypericin (Hy) is a hydrophobic photosensitizer used in photodynamic therapy for cancer therapeutic. In this study, Hy-loaded oil-in-water (O/W) nanoemulsions (NEs) were produced by the ultrasonication method combing different biocompatible oils and surfactants to enhance Hy aqueous solubility and bioavailability. Experimental parameters were optimized by the characterization of droplet size, zeta potential, and physicochemical properties. In vitro studies based on the release profile, cytotoxicity, cell morphology, and Hy intracellular accumulation were assayed. Hy at 100 mg L^-1 was incorporated into the low viscosity (~0.005 Pa s) NEs with spherical droplets averaging 20-40 nm in size and polydispersity index <0.02. Hy release from the NE was significantly higher (4-fold) than its suspension (p < 0.001). The NEs demonstrated good physical stability during storage at 5 °C for at least six months. The Hy-loaded NEs exhibited an IC50 value 6-fold lower than Hy suspension during PDT against breast cancer cell lines (MCF-7). Cell microscopy imaging confirmed the increased cytotoxic effects of Hy-loaded NEs, showing damaged and apoptotic cells. Confocal laser scanning microscopy evidenced greater Hy delivery through NE into MCF-7 cells followed by improved intracellular ROS generation. Our results suggest that the Hy-loaded NEs can improve hypericin efficacy and assist Hy-PDT's preclinical development as a cancer treatment.

Optimization of Production Parameters for Andrographolide-Loaded Nanoemulsion Preparation by Microfluidization and Evaluations of Its Bioactivities in Skin Cancer Cells and UVB Radiation-Exposed Skin

Andrographolide (AG) is an active compound isolated from Andrographis paniculata (Family Acanthaceae). Although it possesses beneficial bioactivities to the skin, there is insufficient information of its applications for treatment of skin disorders due to low water solubility leading to complications in product development. To overcome the problem, an AG-loaded nanoemulsion (AG-NE) was formulated and prepared using a microfluidization technique. This study aimed to investigate the effect of pressure and the number of homogenization cycles (factors) on droplet size, polydispersity index and zeta potential of AG-NE (responses) and to determine the effect of AG-NE on skin cancer cells and UVB irradiation-induced skin disorders in rats. Relationships between factors versus responses obtained from the face-centered central composite design were described by quadratic models. The optimum value of parameters for the production of optimized AG-NE (Op-AG-NE) were 20,000 psi of pressure and 5 homogenization cycles. Op-AG-NE showed promising cytotoxicity effects on the human malignant melanoma- (A375 cells) and non-melanoma cells (A-431 cells) via apoptosis induction with a high selectivity index and also inhibited intracellular tyrosinase activity in the A375 cells. Op-AG-NE could reduce melanin index and healed UVB irradiation exposed skin. Op-AG-NE thus had potential for treatment of skin cancers and skin disorders from exposure to UVB radiation.

Innovative Delivery Systems Loaded with Plant Bioactive Ingredients: Formulation Approaches and Applications

Plants constitute a rich source of diverse classes of valuable phytochemicals (e.g., phenolic acids, flavonoids, carotenoids, alkaloids) with proven biological activity (e.g., antioxidant, anti-inflammatory, antimicrobial, etc.). However, factors such as low stability, poor solubility and bioavailability limit their food, cosmetics and pharmaceutical applications. In this regard, a wide range of delivery systems have been developed to increase the stability of plant-derived bioactive compounds upon processing, storage or under gastrointestinal digestion conditions, to enhance their solubility, to mask undesirable flavors as well as to efficiently deliver them to the target tissues where they can exert their biological activity and promote human health. In the present review, the latest advances regarding the design of innovative delivery systems for pure plant bioactive compounds, extracts or essential oils, in order to overcome the above-mentioned challenges, are presented. Moreover, a broad spectrum of applications along with future trends are critically discussed.

Current Trends on Repurposing and Pharmacological Enhancement of Andrographolide

Andrographolide, the main bioactive component separated from Andrographis paniculata in 1951, has been scrutinized with a modern drug discovery approach for anti-inflammatory properties since 1984. Identification of new uses of existing drugs can be facilitated by searching for evidence linking them to known or yet undiscovered drug targets and human disease states to develop new therapeutic indications.Furthermore, a wide spectrum of biological properties of andrographolide such as anticancer, antibacterial, antiviral, hepatoprotective, antioxidant, anti-malarial, anti-atherosclerosis are also reported. However, poor water solubility and instability limit its clinical application. It becomes crucial to enhance its pharmacological function and find a new treatment option for more diseases. Therefore, this article reviews the major recent developments in andrographolide, including repurposing applications in different diseases and underlying mechanisms, particularly focusing on pharmacological enhancement of andrographolide such as derivatives, chemical modifications with potent biological activity and drug delivery. The repurposing and pharmacological enhancement of andrographolide would not only have exciting therapeutic potential to different diseases to facilitate drug marketing, but also decrease the economic burden on healthcare worldwide.

Anticancer potential of andrographolide from Andrographis paniculata (Burm.f.) Nees and its mechanisms of action

ETHNOPHARMACOLOGICAL RELEVANCE

Synthetic drugs used for cancer treatment have side effects that may be immunosupressive, can cause liver, kidney and cardiac toxicity, and infertility and ovarian failure, among others. Thus, herbal drugs could be used in the cancer treatment as an adjuvant therapy. Andrographis paniculata (Burm.f.) Nees (AP) is one of the traditional herbs used in different alternative medicinal systems such as Ayurveda, Unani, Chinese, Malayi, Siddha, etc. for the treatment of various disorders and diseases including cancer.

AIM OF THE STUDY

The aim of writing this review is to highlight the medicinal importance of AP and its main phytoconstituent andrographolide (AG). The main emphasis was given on the anticancer activity of AG, its proposed mechanisms of action, novel approaches used to improve its biopharmaceutical properties with the perspective of evidence-based research, and its development as an adjuvant therapy for cancer treatment in future.

MATERIALS AND METHODS

Literature survey was conducted and research papers were retrieved from different databases such as Pubmed, Google Scholar, ACS, Wiley online library, ScienceDirect, Springer, and Scopus during 1970-2020. Research articles, review articles, and short communications, etc. were used for this purpose. The papers were selected on the basis of exclusion and inclusion criteria.

RESULTS

Different anticancer mechanisms of AG have been reportedly proven such as cell cycle arrest, apoptosis, NF-κβ inhibition, antiangiogenesis, cytokine inhibition, etc. whereas its pharmacokinetic properties showed its highly protein bound nature, Cyt P400 (CYP) inhibition, low aqueous solubility, poor oral bioavailability, etc. Different novel formulations of AG have been investigated to increase its bioavailability for better efficacy.

CONCLUSION

This review can provide knowledge about the potential applicability of AP or AG as an adjuvant therapy in cancer treatment. Further research is needed before making any conclusion about the efficacy in humans as an adjuvant therapy in cancer.

Nanoformulation Development to Improve the Biopharmaceutical Properties of Fisetin Using Design of Experiment Approach

This study aimed to design an effective nanoparticle-based carrier for the oral delivery of fisetin (FST) with improved biopharmaceutical properties. FST-loaded nanoparticles were prepared with polyvinyl alcohol (PVA) and poly(lactic-co-glycolic acid) (PLGA) by the interfacial deposition method. A central composite design of two independent variables, the concentration of PVA and the amount of PLGA, was applied for the optimization of the preparative parameter. The responses, including average particle size, polydispersity index, encapsulation efficiency, and zeta potential, were assessed. The optimized formulation possessed a mean particle size of 187.9 nm, the polydispersity index of 0.121, encapsulation efficiency of 79.3%, and zeta potential of −29.2 mV. The morphological observation demonstrated a globular shape for particles. Differential scanning calorimetry and powder X-ray diffraction studies confirmed that the encapsulated FST was presented as the amorphous state. The dissolution test indicated a 3.06-fold increase for the accumulating concentrations, and the everted gut sac test showed a 4.9-fold gain for permeability at the duodenum region. In conclusion, the optimized FST-loaded nanoparticle formulation in this work can be developed as an efficient oral delivery system of FST to improve its biopharmaceutic properties.

Andrographis paniculata (Burm. F.) Wall. Ex Nees, Andrographolide, and Andrographolide Analogues as SARS-CoV-2 Antivirals? A Rapid Review

Drug repurposing is commonly employed in the search for potential therapeutic agents. Andrographis paniculata, a medicinal plant commonly used for symptomatic relief of the common cold, and its phytoconstituent andrographolide, have been repeatedly identified as potential antivirals against SARS-CoV-2. In light of new evidence emerging since the onset of the COVID-19 pandemic, this rapid review was conducted to identify and evaluate the current SARS-CoV-2 antiviral evidence for A. paniculata, andrographolide, and andrographolide analogs. A systematic search and screen strategy of electronic databases and gray literature was undertaken to identify relevant primary articles. One target-based in vitro study reported the 3CLpro inhibitory activity of andrographolide as being no better than disulfiram. Another Vero cell-based study reported potential SARS-CoV-2 inhibitory activity for both andrographolide and A. paniculata extract. Eleven in silico studies predicted the binding of andrographolide and its analogs to several key antiviral targets of SARS-CoV-2 including the spike protein-ACE-2 receptor complex, spike protein, ACE-2 receptor, RdRp, 3CLpro, PLpro, and N-protein RNA-binding domain. In conclusion, in silico and in vitro studies collectively suggest multi-pathway targeting SARS-CoV-2 antiviral properties of andrographolide and its analogs, but in vivo data are needed to support these predictions.

Andrographis paniculata (Burm. F) Wall ex Nees: Antiviral properties

Andrographis paniculata is home to a rich variety of molecules especially andrographolide and its derivatives. Clinical properties of the andrographolide are multifarious and include: analgesic, antipyretic, antiretroviral, antiproliferative, antimalarial, antithrombotic, antihyperglycemic, antiurolethial, antilesihmaniasis, hepatoprotective, immune-modulatory, protective against alcohol induced toxicity and cardioproetcive activity and anticancer activity. Andrographolide, neoandrographolide, dehydroandrographolide and several natural and synthetic derivatives of it: 14-deoxy-11,12-didehydroandrographolide and 14-deoxyandrographolide, dehydroandrographolide succinic acid monoester (DAMS), 14-ά-lipoyl andrographolide (AL-1), 14-acetyl-3,9-isopropyl-ideneandrographolide, 14-acetylandrographolide, 3,14,19-triacetylandrographolide, and 3,9-isopropyl-idene andrographolide, are shown to possess significant antiviral activity against HIV, influenza A, HBV, HCV, HPP and HSV. Studies on SARS CoV 2 is restricted to in silico molecular docking studies on viral targets and selected host target proteins. The main targets of andrographolide and its derivatives are fusion and adsorption of virus to the host cell, binding to viral receptor and co-receptor, enzymes involved in DNA/RNA/Genome replication by the virus, translation, post-translation and reverse transcription. Andrographolide as a drug is yet to reach its full therapeutic potential since this molecule shows low bioavailability. Andrographolide therapy is in need of an appropriate delivery system that may increase its bioavailability. Further high-quality studies are needed to firmly establish the clinical efficacy of the plant.

Anti-SARS-CoV-2 Activity of Andrographis paniculata Extract and Its Major Component Andrographolide in Human Lung Epithelial Cells and Cytotoxicity Evaluation in Major Organ Cell Representatives

The coronaviruses disease 2019 (COVID-19) caused by a novel coronavirus (SARS-CoV-2) has become a major health problem, affecting more than 50 million people with over one million deaths globally. Effective antivirals are still lacking. Here, we optimized a high-content imaging platform and the plaque assay for viral output study using the legitimate model of human lung epithelial cells, Calu-3, to determine the anti-SARS-CoV-2 activity of Andrographis paniculata extract and its major component, andrographolide. SARS-CoV-2 at 25TCID50 was able to reach the maximal infectivity of 95% in Calu-3 cells. Postinfection treatment of A. paniculata and andrographolide in SARS-CoV-2-infected Calu-3 cells significantly inhibited the production of infectious virions with an IC50 of 0.036 μg/mL and 0.034 μM, respectively, as determined by the plaque assay. The cytotoxicity profile developed over the cell line representatives of major organs, including liver (HepG2 and imHC), kidney (HK-2), intestine (Caco-2), lung (Calu-3), and brain (SH-SY5Y), showed a CC50 of >100 μg/mL for A. paniculata extract and 13.2-81.5 μM for andrographolide, respectively, corresponding to a selectivity index of over 380. In conclusion, this study provided experimental evidence in favor of A. paniculata and andrographolide for further development as a monotherapy or in combination with other effective drugs against SARS-CoV-2 infection.

Anti-SARS-CoV-2 Activity of Andrographis paniculata Extract and Its Major Component Andrographolide in Human Lung Epithelial Cells and Cytotoxicity Evaluation in Major Organ Cell Representatives

The coronaviruses disease 2019 (COVID-19) caused by a novel coronavirus (SARS-CoV-2) has become a major health problem, affecting more than 50 million people with over one million deaths globally. Effective antivirals are still lacking. Here, we optimized a high-content imaging platform and the plaque assay for viral output study using the legitimate model of human lung epithelial cells, Calu-3, to determine the anti-SARS-CoV-2 activity of Andrographis paniculata extract and its major component, andrographolide. SARS-CoV-2 at 25TCID₅₀ was able to reach the maximal infectivity of 95% in Calu-3 cells. Postinfection treatment of A. paniculata and andrographolide in SARS-CoV-2-infected Calu-3 cells significantly inhibited the production of infectious virions with an IC₅₀ of 0.036 μg/mL and 0.034 μM, respectively, as determined by the plaque assay. The cytotoxicity profile developed over the cell line representatives of major organs, including liver (HepG2 and imHC), kidney (HK-2), intestine (Caco-2), lung (Calu-3), and brain (SH-SY5Y), showed a CC₅₀ of >100 μg/mL for A. paniculata extract and 13.2-81.5 μM for andrographolide, respectively, corresponding to a selectivity index of over 380. In conclusion, this study provided experimental evidence in favor of A. paniculata and andrographolide for further development as a monotherapy or in combination with other effective drugs against SARS-CoV-2 infection.

Phytochemical add-on therapy to DMARDs therapy in rheumatoid arthritis: In vitro and in vivo bases, clinical evidence and future trends

The use of biologically active compounds derived from plants i.e. phytochemicals, have been known for ages for their pharmacological activities in the treatment of autoimmune disorders like rheumatoid arthritis (RA). Besides enormous scientific evidence, the therapeutic potential of phytochemicals is often undervalued. The treatment in RA involves the use of synthetic and biological disease modifying anti-rheumatic drugs (DMARDs). However, the long-term treatment in RA is associated with the risk of gastrointestinal, liver, pulmonary and renal toxicities and serious infections including latent tuberculosis, pneumococcus influenza, herpes zoster and hepatitis. These adverse effects sometimes lead to discontinuation of the therapy. A relatively new vision based on the combination of DMARDs with phytochemicals exhibiting anti-inflammatory, anti-arthritic, anti-oxidant, hepatoprotective and nephroprotective properties for the treatment of RA has achieved substantial importance in the last decade. From this perspective, the present review focuses on the combination of DMARDs (primarily MTX) with phytochemicals that have shown synergistic therapeutic effects while decreasing the toxic repercussions of current RA therapy. The review covers recent evidences of such combination studies that have shown promising results both in experimental arthritic models and clinical arthritis. Few of the combinations including resveratrol, sinomenine, coenzyme Q10 exhibited considerable interest because of their efficacy as an adjuvant to the MTX/standard DMARDs therapy in clinical trials. Besides giving an overview of such combination studies the review also critically discusses the limitations with the use of phytochemicals (e.g. solubility, permeability and bioavailability) compromising their clinical application. Additionally, it stresses upon the need of novel delivery systems and pharmaceutical technologies to increase the therapeutic efficacy of the combination therapy. Overall, the review unveils the potential of phytochemicals in combination with DMARDs with increased tolerability and superior efficacy in further refining the future of the RA therapy.

Protective Effect of Natural Products against Huntington's Disease: An Overview of Scientific Evidence and Understanding Their Mechanism of Action

Huntington's disease (HD), a neurodegenerative disease, normally starts in the prime of adult life, followed by a gradual occurrence of characteristic psychiatric disturbances and cognitive and motor dysfunction. To the best of our knowledge, there is no treatment available to completely mitigate the progression of HD. Among various therapeutic approaches, exhaustive literature reports have confirmed the medicinal benefits of natural products in HD experimental models. Building on this information, this review presents a brief overview of the neuroprotective mechanism(s) of natural products against in vitro/in vivo models of HD. Relevant studies were identified from several scientific databases, including PubMed, ScienceDirect, Scopus, and Google Scholar. After screening through literature from 2005 to the present, a total of 14 medicinal plant species and 30 naturally isolated compounds investigated against HD based on either in vitro or in vivo models were included in the present review. Behavioral outcomes in the HD in vivo model showed that natural compounds significantly attenuated 3-nitropropionic acid (3-NP) induced memory loss and motor incoordination. The biochemical alteration has been markedly alleviated with reduced lipid peroxidation, increased endogenous enzymatic antioxidants, reduced acetylcholinesterase activity, and increased mitochondrial energy production. Interestingly, following treatment with certain natural products, 3-NP-induced damage in the striatum was ameliorated, as seen histologically. Overall, natural products afforded varying degrees of neuroprotection in preclinical studies of HD via antioxidant and anti-inflammatory properties, preservation of mitochondrial function, inhibition of apoptosis, and induction of autophagy.

Nanoemulsions for health, food, and cosmetics: a review

Nanoemulsions are gaining importance in healthcare and cosmetics sectors as a result of the unique properties of nanosized droplets, such as high surface area. Here we review nanotechnology and nanoemulsions with focus on emulsifiers and nanoemulsifiers, and applications for drugs and vaccines delivery, cancer therapy, inflammation treatment, cosmetics, perfumes, polymers, and food. We discuss nanoemulsion safety and properties, e.g., stability, emulsification, solubility, molecular number and arrangements, ionic strength, pH and temperature.

Current approaches in lipid-based nanocarriers for oral drug delivery

Lipid-based nanocarriers have gained much interest as carriers of drugs with poor oral bioavailability because of their remarkable advantages like low toxicity, affordable scale-up manufacture, strong biocompatibility or high drug loading efficiency. The potential of these nanocarriers lies in their ability to improve the gastrointestinal stability, solubility and permeability of their cargo drugs. However, achieving efficient oral drug delivery through lipid-based nanocarriers is a challenging task, since they encounter multiple physicochemical barriers along the gastrointestinal tract, e.g. the gastric acidic content, the intestinal mucus layer or the enzymatic degradation, that they must surmount to reach their target. These limitations may be turned into opportunities through a rational design of lipid-based nanocarriers. For that purpose, this review focuses on the main challenges of the oral route indicating the strategies undertaken for lipid-based nanocarriers in order to overcome them. Understanding their shortcomings and identifying their strengths will determine the future clinical success of lipid-based nanocarriers.

Enhanced Lymphatic Delivery of Methotrexate Using W/O/W Nanoemulsion: In Vitro Characterization and Pharmacokinetic Study

Methotrexate, which is widely used in the treatment of cancer and immune-related diseases, has limitations in use because of its low bioavailability, short half-life, and tissue toxicity. Thus, in this study, a nano-sized water-in-oil-in-water (W/O/W) double emulsion containing methotrexate was prepared to enhance its lymphatic delivery and bioavailability. Based on the results from solubility testing and a pseudo-ternary diagram study, olive oil as the oil, Labrasol as a surfactant, and ethanol as a co-surfactant, were selected as the optimal components for the nanoemulsion. The prepared nanoemulsion was evaluated for size, zeta potential, encapsulation efficiency, pH, morphology, and in vitro release profiles. Furthermore, pharmacokinetics and lymphatic targeting efficiency were assessed after oral and intravenous administration of methotrexate-loaded nanoemulsion to rats. Mean droplet size, zeta potential, encapsulation efficiency, and pH of formulated nanoemulsion were 173.77 ± 5.76 nm, -35.63 ± 0.78 mV, 90.37 ± 0.96%, and 4.07 ± 0.03, respectively. In vitro release profile of the formulation indicated a higher dissolution and faster rate of methotrexate than that of free drug. The prepared nanoemulsion showed significant increases in maximum plasma concentration, area under the plasma concentration-time curve, half-life, oral bioavailability, and lymphatic targeting efficiency in both oral and intravenous administration. Therefore, our research proposes a methotrexate-loaded nanoemulsion as a good candidate for enhancing targeted lymphatic delivery of methotrexate.

Investigation of 1,2-Dimyristoyl-sn-Glycero-3-Phosphoglycerol-Sodium (DMPG-Na) Lipid with Various Metal Cations in Nanocochleate Preformulation: Application for Andrographolide Oral Delivery in Cancer Therapy

This study aimed at carrying out a preformulation investigation of nanocochleates (NCs) and develop andrographolide-loaded nanocochleates. Preformulation study comprised of exploring the effect of trivalent and divalent ions on transition temperature (TT) of lipid (DMPG-Na), on particle size (PS), entrapment efficacy (EE), zeta potential (ZP) of NCs, and effect of NCs on change in lipid solubility post-NC formation. Further, the andrographolide-loaded nanocochleates made with CaCl₂ (ANDNCs) were characterized for ZP, PS, EE, X-ray powder diffraction (PXRD), differential scanning calorimetry (DSC), transition electron microscopy (TEM), in vitro release studies, in vitro anticancer potential on the cell line of human breast cancer (MCF-7), in vivo oral pharmacokinetic studies, and tissue distribution in female Wistar rats. Nanocochleates developed with CaCl₂ had a significant reduction in PS (1.78-fold) and ZP (1.38-fold), and elevation of EE (1.17-fold) as compared to AlCl₃ developed NCs. Trivalent ions demonstrated elevation of TT as compared to divalent ions. Spiral-shaped ANDNCs demonstrated ZP, PS, and EE of - 121.46 ± 15.12 mV, 360 ± 47 nm, and 68.12 ± 3.81% respectively. In vitro release study of ANDNCs showed a strong pH-dependent release profile due to hydrogen bonding between NCs and andrographolide (AND). Formulated ANDNCs demonstrated 26.99-fold decrease in IC50 value as compared to free AND. Additionally, the oral bioavailability of AND from ANDNCs improved by 1.81-fold as compared to free AND. Furthermore, ANDNCs showed minimum accumulation within the vital organs such as liver, kidney, and spleen. Briefly, the preformulation study laid a platform for better understanding the NCs and its components. Further, developed ANDNCs revealed superior physiochemical properties to be used as an alternative for a clinical setting.

Biomimetic Synthesis and Evaluation of Interconnected Bimodal Mesostructured MSF@Poly(Ethyleneimine)s for Improved Drug Loading and Oral Adsorption of the Poorly Water-Soluble Drug, Ibuprofen

Purpose

The aim of this study was to improve the oral bioavailability and anti-inflammatory activity of the poorly soluble drug ibuprofen (IBU) by employing a new kind of poly(ethyleneimine)s (PEIs)-based mesocellular siliceous foam (MSF) called B-BMSF@PEI as drug carrier.

Methods

B-BMSF@PEI was biomimetically synthesized by using PEIs as templates, catalysts and scaffolds under ambient conditions, and the structural characteristics, including size, morphology, mesoscopic structure and pore properties, were estimated by TEM, SEM, FTIR and N₂ desorption/adsorption measurement. Then, IBU was incorporated into B-BMSF@PEI at the drug:carrier weight ratio of 1:1. The structural features of IBU before and after drug loading were systemically characterized. IBU and B-BMSF@PEI were then subject to in vitro drug release study and wettability analysis. Finally, in vivo pharmacokinetics and anti-inflammatory pharmacodynamics studies were carried out to evaluate the efficacy of B-BMSF@PEI on improving the oral adsorption of IBU.

Results

The results demonstrated that B-BMSF@PEI was a meso–meso porous silica material with foam appearance. It consisted of uniform spherical cells (40 nm) with interconnected pore networks. IBU can be successfully loaded into B-BMSF@PEI with high efficiency (as high as 39.53%), and crystal IBU was effectively converted to an amorphous state during this process. Benefiting from the great architectures of B-BMSF@PEI, IBU/B-BMSF@PEI performed good wetting property and significantly improved the dissolution rate in both simulated gastric fluid (SGF) and simulated intestinal fluid (SIF). Notably, IBU exhibited very satisfactory relative bioavailability (681.4%) and anti-inflammatory effects (the inhibition rates were between the ranges of 113.5% to 1504.3%).

Conclusion

B-BMSF@PEI with bimodal mesoporous system and interconnected nanopores was obtained owing to the dynamic self-assembly functions of PEIs. It had superiority in drug loading and could improve the oral adsorption of ibuprofen to a satisfactory level.

Targeting hypoxia-inducible factor-1, for cancer treatment: Recent advances in developing small-molecule inhibitors from natural compounds

Rapid progress in molecular cancer biology coupled with the discovery of novel oncology drugs has opened new horizons for cancer target discovery. As one of the crucial signaling pathways related to tumorigenesis, hypoxia-inducible factor-1 (HIF-1) coordinates the activity of many transcription factors and their downstream molecules that impact tumor growth and metastasis. Accumulating evidence suggests that the transcriptional responses to acute hypoxia are mainly attributable to HIF-1α. Moreover, the overexpression of HIF-1α in several solid cancers has been found to be strongly associated with poor prognosis. Thus, pharmacological targeting of the HIF-1 signaling pathways has been considered as a new strategy for cancer therapy in the recent years. Although over the past decade, tremendous efforts have been made in preclinical studies to develop new HIF-1 inhibitors from natural products (reservoirs of novel therapeutic agents), to date, these efforts have not been successfully translated into clinically available treatments. In this review, we provide new insights into the bio-pharmacological considerations for selecting natural compounds as potential HIF-1 inhibitors to accelerate anti-cancer drug development. In addition, we highlighted the importance of assessing the dependency of cancer on HIF1A to shortlist cancer types as suitable disease models. This may subsequently lead to new paradigms for discovering more HIF-1 inhibitors derived from natural products and facilitate the development of potent therapeutic agents targeting specific cancer types.

Self-Nanoemulsifying Drug Delivery Systems for Enhancing Solubility, Permeability, and Bioavailability of Sesamin

Sesamin (SSM) is a water-insoluble compound that is easily eliminated by liver metabolism. To improve the solubility and bioavailability of SSM, this study developed and characterized a self-nanoemulsifying drug delivery system (SNEDDS) for the oral delivery of SSM and conducted pharmacokinetic assessments. Oil and surfactant materials suitable for SNEDDS preparation were selected on the basis of their saturation solubility at 37 ± 0.5 °C. The mixing ratios of excipients were determined on the basis of their dispersibility, transmittance (%), droplet sizes, and polydispersity index. An SNEDDS (F10) formulation comprising glyceryl trioctanoate, polyoxyethylene castor oil, and Tween 20 at a ratio of 10:10:80 (w/w/w) was the optimal formulation. This formulation maintained over 90% of its contents in different storage environments for 12 weeks. After the self-emulsification of SNEDDS, the SSM dispersed droplet size was 66.4 ± 31.4 nm, intestinal permeability increased by more than three-fold, relative bioavailability increased by approximately 12.9-fold, and absolute bioavailability increased from 0.3% to 4.4%. Accordingly, the developed SNEDDS formulation can preserve SSM's solubility, permeability, and bioavailability. Therefore, this SNEDDS formulation has great potential for the oral administration of SSM, which can enhance its pharmacological application value.

Antioxidant Property and Bactericidal Activity of Linum usitatissimum Seed Essential Oil Nanoemulsion (LSEO-NE) on Staphylococcus aureus

Background: Linum usitatissimum Seed Essential Oil (LSEO) as an efficient antimicrobial compound contains various types of phytochemicals, such as lignans and phenols. Objectives: In the current study, we produced LSEO nanoemulsion (LSEO-NE) to study its antioxidant capacity and bactericidal activity against Staphylococcus aureus. Methods: The LSEO-NE was produced using the ultrasonication method and characterized by Atomic Force Microscopy (AFM), Dynamic Light Scattering (DLS), and Scanning Electron Microscopy (SEM). Then, we measured its antioxidant activity utilizing both ABTS and DPPH tests at four different LSEO-NE concentrations (200, 600, 800, and 1000 µg/mL) compared to glutathione. Finally, we evaluated its bactericidal activity on S. aureus by studying Antibiotic Susceptibility Testing (AST) using LSEO-NE-smeared discs compared to non-smeared and kanamycin discs. Results: The 67.3 nm droplets of LSEO-NE with PDI of 0.452 exhibited strong antioxidant activity, similar to glutathione, in both ABTS (IC50 = 350 µg/mL) and DPPH (IC50 = 235 µg/mL) tests. Moreover, the AST results revealed the significant sensitivity of S. aureus to LSEO-NE-smeared discs when compared to non-smeared and kanamycin discs. Conclusions: According to the results, LSEO-NE can be applied as a safe, natural, and effective antibiotic for bacterial infections caused by S. aureus in most organs, such as the respiratory system and skin. However, further in vivo studies are required to evaluate the LSEO-NE antibacterial efficiency against other pathogenic S. aureus strains.

Oral Bioavailability Enhancement and Anti-Fatigue Assessment of the Andrographolide Loaded Solid Dispersion

Andrographolide (AG), a major diterpene lactone isolated from Andrographis paniculata (Burm. f.) Nees (Acanthaceae), possesses a wide spectrum of biological activities. However, its poor water solubility and low bioavailability limit its clinical application. Therefore, this study aimed to develop a solid dispersion (SD) formulation to increase the aqueous solubility and dissolution rate of AG. Different drug-polymer ratios were used to prepare various SDs. The optimized formulation was characterized for differential scanning calorimetry, Fourier transform infrared spectroscopy, and powder X-ray diffraction. The analysis indicated that the optimized SD enhanced AG solubility and dissolution rates by changing AG crystallinity to an amorphous state. The dissolution behaviors of the optimum SD composed of an AG-polyvinylpyrrolidone K30-Kolliphor EL ratio of 1:7:1 (w/w/w) resulted in the highest accumulated dissolution (approximately 80%). Pharmacokinetic studies revealed that C_max/dose and the AUC/dose increased by 3.7-fold and 3.0-fold, respectively, compared with AG suspension. Furthermore, pretreatment using the optimized AG-SD significantly increased the swimming time to exhaustion by 1.7-fold and decreased the plasma ammonia level by 71.5%, compared with the vehicle group. In conclusion, the optimized AG-SD formulation appeared to effectively improve its dissolution rate and oral bioavailability. Moreover, the optimized AG-SD provides a promising treatment against physical fatigue.