Preparation and characterization of nano-emulsion formulations of Asparagus densiflorus root and aerial parts extracts: evaluation of in-vitro antibacterial and anticancer activities of nano-emulsion versus pure plant extract.

OBJECTIVE: Preparation and characterization of nano-emulsion formulations for Asparagus densiflorus aerial and root parts extracts. SIGNIFICANCE: Genus Asparagus is known for its antimicrobial and anticancer activities, however, freeze dried powder of aqueous - alcoholic extract prepared in this study, exhibited a limited water solubility, limiting its therapeutic application. Thus, encapsulation of its phytochemicals into nano-emulsion is proposed as a solution to improve water solubility, and facilitate its clinical translation. METHODS: the composition of extracts for both aerial and root parts of Asparagus densiflorus was identified by HPLC and LC-MS analysis. Nano-emulsion was prepared via homogenization where a mixture of Castor oil: phosphate buffered saline (10 mM, pH 7.4): Tween 80: PEG 600 in a ratio of 10: 5: 2.5: 2.5, respectively. Nano-emulsion formulations were characterized for particle size, polydispersity index (PDI), zeta potential, TEM, viscosity and pH. Then, the antibacterial and anticancer activities of nano-emulsion formulations versus their pure plant counterparts was assessed. RESULTS: The analysis of extracts identified several flavonoids, phenolics, and saponins which were reported to have antimicrobial and anticancer activities. Nano-emulsion formulations were monodispersed with droplet sizes ranging from 80.27 ± 2.05 to 111.16 ± 1.97 nm, and polydispersity index ≤0.3. Nano-emulsion formulations enhanced significantly the antibacterial (multidrug resistant bacteria causing skin and dental soft tissues infections) and anticancer (HuH7, HEPG2, H460 and HCT116) activities compared to their pure plant extract counterparts. CONCLUSION: Employing a nano-delivery system as a carrier for phytochemicals might be an effective strategy to enhance their pharmacological activity, overcome their limitations, and ultimately increase their potential for clinical applications.

In-vitro cytotoxic and anti-inflammatory potential of Asparagus densiflorus meyeri and its phytochemical investigation.

Genus Asparagus is well known for its pharmacological activities and ethnopharmacological applications.  In folk medicine, it is used in the management of several diseases such as diabetes, inflammations, and rheumatism. This work aimed to investigate the potential of Asparagus densiflorus meyeri root & aerial parts extracts as cytotoxic and anti-inflammatory and the investigation of their chemical profile. GC analysis & Folin-Ciocalteu and gravimetric methods were used respectively to estimate the lipoidal, phenolic, and saponin contents. MTT assay was conducted using two cell lines (MCF-7 & HepG2) to investigate the cytotoxic and anti-inflammatory activity using TNF-α stimulated MCF-7 cells through monitoring the level of nitric oxide release and NF-κB gene expression. Preliminary phytochemical investigation indicated that both extracted parts are equally rich in saponins, flavonoids, carbohydrates and/or glycosides, and sterols and/or triterpenes. Palmitic acid and ß sitosterol represented the major saturated fatty acids and sterol, respectively. A significant cytotoxic activity against MCF-7 cells was recorded for DCM extract (IC50 26.13 µg/ml). All tested extracts showed a significant decrease in NO release and NF-κB gene expression thus it possesses a potential anti-inflammatory activity. A. densiflorus meyeri is considered a good candidate as a food supplement for protection from malignancy.

Preparation and characterization of Sorafenib nano-emulsion: impact on pharmacokinetics and toxicity; an in vitro and in vivo study.

Hepatocellular carcinoma (HCC) ranks as the third leading cause of cancer-related deaths worldwide. Current treatment strategies include surgical resection, liver transplantation, liver-directed therapy, and systemic therapy. Sorafenib (Sor) is the first systemic drug authorized by the US Food and Drug Administration (FDA) for HCC treatment. Nevertheless, the conventional oral administration of Sor presents several limitations: poor solubility, low bioavailability, drug resistance development, and off-target tissue accumulation, leading to numerous adverse effects. Nano-emulsion, a nano-delivery system, is a viable carrier for poorly water-soluble drugs. It aims to enhance drug bioavailability, target organ accumulation, and reduce off-target tissue exposure, thus improving therapeutic outcomes while minimizing side effects. This study formulated Sor nano-emulsion (Sor NanoEm) using the homogenization technique. The resultant nano-emulsion was characterized by particle size (121.75 ± 12 nm), polydispersity index (PDI; 0.310), zeta potential (-12.33 ± 1.34 mV), viscosity (34,776 ± 3276 CPs), and pH (4.38 ± 0.3). Transmission Electron Microscopy exhibited spherical nano-droplets with no aggregation signs indicating stability. Furthermore, the encapsulation of Sor within the nano-emulsion sustained its release, potentially reducing the frequency of therapeutic doses. Cytotoxicity assessments on the HepG2 cell line revealed that Sor NanoEm had a significantly (P < 0.05) more potent cytotoxic effect compared to Sor suspension. Subsequent tests highlighted superior pharmacokinetic parameters and reduced dosage requirements of Sor NanoEm in mice. It exhibited an enhanced safety profile, particularly in behavior, brain, and liver, compared to its suspended form. These findings underscore the enhanced pharmacological and toxicological attributes of Sor Nano-emulsion, suggesting its potential utility in HCC treatment.

Investigating the Antibacterial Activity and Safety of Zinc Oxide Nanoparticles versus a Commercial Alcohol-Based Hand-Sanitizer: Can Zinc Oxide Nanoparticles Be Useful for Hand Sanitation?

Hand hygiene is the key factor to control and prevent the spread of infections, for example, hospital-acquired infections (HAIs). People commonly use alcohol-based hand sanitizers to assure hand hygiene. However, frequent use of alcohol-based hand sanitizers in a pandemic situation (e.g., COVID-19) was associated with serious drawbacks such as skin toxicity including irritation, skin dermatitis, and skin dryness or cracking, along with peeling, redness, or itching with higher possibility of infection. This demands the development of alternative novel products that are effective as alcohol-based hand sanitizers but have no hazardous effects. Zinc oxide nanoparticles (ZnO-NPs) are known to have broad-spectrum antimicrobial activity, be compatible with the biological system and the environment, and have applicable and economic industrial-scale production. Thus, ZnO-NPs might be a good candidate for hand sanitation. To the best of our knowledge, the antibacterial activity of ZnO-NPs in comparison to alcohol-based hand sanitizers has not yet been studied. In the present work, a comparative study of the antibacterial activity of ZnO-NPs vs. Sterillium, a commercial alcohol-based hand sanitizer that is commonly used in Egyptian hospitals, was performed against common microorganisms known to cause HAIs in Egypt, including Acinetobacter baumannii, Klebsiella pneumoniae, Methicillin-resistant Staphylococcus aureus (MRSA), and Staphylococcus aureus. The safety profiles of ZnO-NPs and Sterillium were also assessed. The obtained results demonstrated the superior antibacterial activity and safety of ZnO-NPs compared to Sterillium. Therefore, ZnO-NPs could be a promising candidate for hand sanitation in comparison to alcohol-based hand sanitizers; however, several studies related to long-term toxicity and stability of ZnO-NPs and investigations into their antimicrobial activity and safety in healthcare settings are still required in the future to ascertain their antimicrobial activity and safety.

Antimicrobial Activity of Azithromycin Encapsulated into PLGA NPs: A Potential Strategy to Overcome Efflux Resistance.

Antimicrobial resistance represents a public health problem with a major negative impact on health and socioeconomic development, and is one of the biggest threats in the modern era. This requires the discovery of new approaches to control microbial infections. Nanomedicine could be one of the promising strategies to improve the treatment of microbial infections. Polymer nanoparticles (PNPs) were reported to overcome the efflux-resistant mechanism toward chemotherapeutic agents. However, to the best of our knowledge, no studies were performed to explore their ability to overcome the efflux-resistant mechanism in bacteria. In the current study, azithromycin (AZI), a macrolide antibiotic, was encapsulated into a biocompatible polymer, poly (lactic-co-glycolic acid) (PLGA) using the nano-precipitation method. The effect of the drug to polymer ratio, surfactant, and pH of the aqueous medium on particle size and drug loading percentage (DL%) were investigated in order to maximize the DL% and control the size of NPs to be around 100 nm. The antibacterial activity of AZI-PLGA NPs was investigated against AZI-resistant bacteria; Methicillin-resistant Staphylococcus aureus (MRSA) and Enterococcus faecalis (E. faecalis), where the efflux mechanism was demonstrated to be one of the resistant mechanisms. AZI-PLGA NPs were safer than free AZI, as revealed from the cytotoxicity test, and were able to overcome the efflux-resistant mechanism, as revealed by decreasing the MIC of AZI-PLGA NPs by four times than free AZI. The MIC value reduced from 256 to 64 µg/mL and from >1000 to 256 µg/mL for MRSA and E. faecalis, respectively. Therefore, encapsulation of AZI into PNPs was shown to be a promising strategy to overcome the efflux-resistant mechanism towards AZI and improve its antibacterial effect. However, future investigations are necessary to explore the effect (if any) of particle size, surface charge, and material composition of PNPs on antibacterial activity. Moreover, it is essential to ascertain the safety profiles of these PNPs, the possibility of their large-scale manufacture, and if this concept could be extended to other antibiotics.

Rhamnolipid Nano-Micelles Inhibit SARS-CoV-2 Infection and Have No Dermal or Eye Toxic Effects in Rabbits.

Hand hygiene is considered to be the key factor in controlling and preventing infection, either in hospital care settings or in the community. Alcohol-based hand sanitizers are commonly used due to their rapid action and broad spectrum of microbicidal activity, offering protection against bacteria and viruses. However, their frequent administration during COVID-19 pandemic was associated with serious hazards, such as skin toxicity, including irritation, skin dermatitis, skin dryness or cracking, along with peeling redness or itching, with the higher possibility of getting infections. Thus, there is a need to find alternative and novel approaches for hand sanitation. In our previous publications, we reported that rhamnolipids nano-micelles had a comparable antibacterial activity to alcohol-based hand sanitizer and a lower cytotoxicity against human dermal fibroblast cells. In the current study, we investigated the antiviral activity of rhamnolipids nano-micelles against SARS-CoV-2. There was no cytotoxic effect on Vero cells noted at the tested concentrations of rhamnolipids nano-micelles. The rhamnolipids nano-micelles solution at 20, 78, and 312 µg/mL all demonstrated a significant (p < 0.05) decrease of virus infectivity compared to the virus only and the blank vehicle sample. In addition, an acute irritation test was performed on rabbits to further ascertain the biosafety of rhamnolipids nano-micelles. In the eye and skin irritation tests, no degree of irritation was recorded after topical application of rhamnolipids nano-micelles. In addition, histopathological, biomarker, and hematological analyses from animals treated with rhamnolipids nano-micelles were identical to those recorded for untreated animal. From the above, we can conclude that rhamnolipids nano-micelles are a good candidate to be used as a hand sanitizer instead of alcohol-based hand sanitizers. However, they must still be tested in the future among healthcare workers (HCW) in a health care setting to ascertain their antimicrobial efficacy and safety compared to alcohol-based hand sanitizers.

Rhamnolipid Nano-Micelles versus Alcohol-Based Hand Sanitizer: A Comparative Study for Antibacterial Activity against Hospital-Acquired Infections and Toxicity Concerns.

Hospital-acquired infections (HAIs) are considered to be a major global healthcare challenge, in large part because of the development of microbial resistance to currently approved antimicrobial drugs. HAIs are frequently preventable through infection prevention and control measures, with hand hygiene as a key activity. Improving hand hygiene was reported to reduce the transmission of healthcare-associated pathogens and HAIs. Alcohol-based hand sanitizers are commonly used due to their rapid action and broad spectrum of microbicidal activity, offering protection against bacteria and viruses. However, their frequent administration has been reported to be associated with many side effects, such as skin sensitivity, skin drying, and cracks, which promote further skin infections. Thus, there is an essential need to find alternative approaches to hand sanitation. Rhamnolipids are glycolipids produced by Pseudomonas aeruginosa, and were shown to have broad antimicrobial activity as biosurfactants. We have previously demonstrated the antimicrobial activity of rhamnolipid nano-micelles against selected drug-resistant Gram-negative (Salmonella Montevideo and Salmonella Typhimurium) and Gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumoniae). To the best of our knowledge, the antimicrobial activity of rhamnolipid nano-micelles in comparison to alcohol-based hand sanitizers against microorganisms commonly causing HAIs in Egypt-such as Acinetobacter baumannii and Staphylococcus aureus-has not yet been studied. In the present work, a comparative study of the antibacterial activity of rhamnolipid nano-micelles versus alcohol-based hand sanitizers was performed, and their safety profiles were also assessed. It was demonstrated that rhamnolipid nano-micelles had a comparable antibacterial activity to alcohol-based hand sanitizer, with a better safety profile, i.e., rhamnolipid nano-micelles are unlikely to cause any harmful effects on the skin. Thus, rhamnolipid nano-micelles could be recommended to replace alcohol-based hand sanitizers; however, they must still be tested by healthcare workers in healthcare settings to ascertain their antimicrobial activity and safety.

Rhamnolipids Nano-Micelles as a Potential Hand Sanitizer.

COVID-19 is a pandemic disease caused by the SARS-CoV-2, which continues to cause global health and economic problems since emerging in China in late 2019. Until now, there are no standard antiviral treatments. Thus, several strategies were adopted to minimize virus transmission, such as social distancing, face covering protection and hand hygiene. Rhamnolipids are glycolipids produced formally by Pseudomonas aeruginosa and as biosurfactants, they were shown to have broad antimicrobial activity. In this study, we investigated the antimicrobial activity of rhamnolipids against selected multidrug resistant bacteria and SARS-CoV-2. Rhamnolipids were produced by growing Pseudomonas aeruginosa strain LeS3 in a new medium formulated from chicken carcass soup. The isolated rhamnolipids were characterized for their molecular composition, formulated into nano-micelles, and the antibacterial activity of the nano-micelles was demonstrated in vitro against both Gram-negative and Gram-positive drug resistant bacteria. In silico studies docking rhamnolipids to structural and non-structural proteins of SARS-CoV-2 was also performed. We demonstrated the efficient and specific interaction of rhamnolipids with the active sites of these proteins. Additionally, the computational studies suggested that rhamnolipids have membrane permeability activity. Thus, the obtained results indicate that SARS-CoV-2 could be another target of rhamnolipids and could find utility in the fight against COVID-19, a future perspective to be considered.

An investigation of rhinovirus infection on cellular uptake of poly (glycerol-adipate) nanoparticles.

Viral infections represent 44% of newly emerging infections, and as is shown by the COVID-19 outbreak constitute a major risk to human health and wellbeing. Although there are many efficient antiviral agents, they still have drawbacks such as development of virus resistance and accumulation within off-target organs. Encapsulation of antiviral agents into nanoparticles (NPs) has been shown to improve bioavailability, control release, and reduce side effects. However, there is little quantitative understanding of how the uptake of NPs into virally infected cells compares to uninfected cells. In this work, the uptake of fluorescently labeled polymer NPs was investigated in several models of rhinovirus (RV) infected cells. Different multiplicities of RV infections (MOI) and timings of NPs uptake were also investigated. In some cases, RV infection resulted in a significant increase of NPs uptake, but this was not universally noted. For HeLa cells, RV-A16 and RV-A01 infection elevated NPs uptake upon increasing the incubation time, whereas at later timepoints (6 h) a reduced uptake was noted with RV-A01 infection (owing to decreased cell viability). Beas-2B cells exhibited more complex trends: decreases in NPs uptake (cf. uninfected cells) were observed at short incubation times following RV-A01 and RV-A16 infection. At later incubation times (4 h), we found a marked decrease of NPs uptake for RV-A01 infected cells but an increase in uptake with RV-A16 infected cells. Where increases in NPs uptake were found, they were very modest compared to results previously reported for a hepatitis C/ Huh7.5 cell line model. An increase in RV dose (MOI) was not associated with any notable change of NPs uptake. We argue that the diverse endocytic pathways among the different cell lines, together with changes in virus nature, size, and entry mechanism are responsible for these differences. These findings suggest that NPs entry into virally infected cells is a complex process, and further work is required to unravel the different factors which govern this. Undertaking this additional research will be crucial to develop potent nanomedicines for the delivery of antiviral agents.

A molecular docking study repurposes FDA approved iron oxide nanoparticles to treat and control COVID-19 infection.

COVID-19, is a disease resulting from the SARS-CoV-2 global pandemic. Due to the current global emergency and the length of time required to develop specific antiviral agent(s) and a vaccine for SARS-CoV-2, the world health organization (WHO) adopted the strategy of repurposing existing medications to treat COVID-19. Iron oxide nanoparticles (IONPs) were previously approved by the US food and drug administration (FDA) for anemia treatment and studies have also demonstrated its antiviral activity in vitro. Therefore, we performed a docking study to explore the interaction of IONPs (Fe2O3 and Fe3O4) with the spike protein receptor binding domain (S1-RBD) of SARS-CoV-2 that is required for virus attachment to the host cell receptors. A similar docking analysis was also performed with hepatitis C virus (HCV) glycoproteins E1 and E2. These studies revealed that both Fe2O3 and Fe3O4 interacted efficiently with the SARS-CoV-2 S1-RBD and to HCV glycoproteins, E1 and E2. Fe3O4 formed a more stable complex with S1-RBD whereas Fe2O3 favored HCV E1 and E2. These interactions of IONPs are expected to be associated with viral proteins conformational changes and hence, viral inactivation. Therefore, we recommend FDA-approved-IONPs to proceed for COVID-19 treatment clinical trials.

The potential anti-infective applications of metal oxide nanoparticles: A systematic review.

Microbial infections present a major global healthcare challenge, in large part because of the development of microbial resistance to the currently approved antimicrobial drugs. This demands the development of new antimicrobial agents. Metal oxide nanoparticles (MONPs) are a class of materials that have been widely explored for diagnostic and therapeutic purposes. They are reported to have wide-ranging antimicrobial activities and to be potent against bacteria, viruses, and protozoans. The use of MONPs reduces the possibility of resistance developing because they have multiple mechanisms of action (including via reactive oxygen species generation), simultaneously attacking many sites in the microorganism. However, despite this there are to date no MONPs clinically approved for antimicrobial therapy. This review explores the recent literature in this area, discusses the mechanisms of MONP action against microorganisms, and considers the barriers faced to the use of MONPs in humans. These include biological challenges, of which the potential for an immune response and off-target toxicity are key. We explore in detail the possible benefits/disbenefits of an immune response being initiated, and consider the effect of production method (chemical vs. green synthesis) on cytotoxicity. There are also a number of technical and manufacturing challenges hindering MONP translation to the clinic which are additionally discussed in depth. In the short term, there are potentially some "quick wins" from the repurposing of already-approved nanoparticle-based medicines for anti-infective applications, but a number of hurdles, both technical and biological, lie in the path to long-term clinical translation of new MONP-based formulations. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Therapeutic Approaches and Drug Discovery > Emerging Technologies Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials.

The Effect of Molecular Properties on Active Ingredient Release from Electrospun Eudragit Fibers.

The formation of nanoscale fibers from pH-sensitive polymers is a route which has been widely explored for targeted drug delivery. In particular, the Eudragit L100 and S100 families of polymers have received significant attention for this purpose. However, while in some cases it is shown that making drug-loaded Eudragit polymers effectively prevents drug release in low-pH media where the polymer is insoluble, this is not always the case, and other studies have reported significant amounts of drug release at acidic pHs. In this study, we sought to gain insight into the factors influencing the release of active ingredients from Eudragit S100 (ES100) fibers. A family of materials was prepared loaded with the model active ingredients (AIs) benzoic acid, 1-naphthoic acid, 1-naphthylamine, and 9-anthracene carboxylic acid. Analogous systems were prepared with an AI-loaded core and an ES100 sheath. The resultant fibers were smooth and cylindrical in the majority of cases, and X-ray diffraction and differential scanning calorimetry showed them to comprise amorphous solid dispersions. When AI release from the monolithic fibers was probed, it was found that there was significant release at pH 1 in all cases except with 9-anthracene carboxylic acid. Analysis of the results indicated that both the molecular weight of the AI and its acidity/basicity are important in controlling release, with lower molecular weight AIs and basic species released more quickly. The same release trends are seen with the core/shell fibers, but AI release at pH 1 is attenuated. The most significant change between the monolithic and core/shell systems was observed in the case of 1-naphthylamine. Mathematical equations were devised to connect molecular properties and AI release under acidic conditions.

Enhanced nanoparticle uptake into virus infected cells: Could nanoparticles be useful in antiviral therapy?

Virus infections cause diseases of different severity ranged from mild infection e.g. common cold into life threatening diseases e.g. Human Immunodeficiency virus (HIV), Hepatitis B. Virus infections represent 44% of newly emerging infections. Although there are many efficient antiviral agents, they still have drawbacks due to accumulation at off target organs and developing of virus resistance due to virus mutation. Therefore, developing a delivery system that can selectively target drug into affected organs and avoid off target accumulation would be a highly advantageous strategy to improve antiviral therapy. Nanoparticles (NP) can be effectively targeted to the liver, and therefore it could be used for improving therapy of hepatic virus infections including hepatitis B virus and hepatitis C virus (HCV). Many studies were performed to encapsulate antiviral agents into nano-delivery system to improve their pharmacokinetics parameters to have a better therapeutic efficacy with lower side effects. However, the effect of virus infection on the uptake of NP has not yet been studied in detail. The latter is a crucial area as modulation of endocytic uptake of nanoparticles could impact on reduce potential therapeutic usefulness of antiviral agents loaded into nano-delivery system. In this study, a fluorescently-labelled polymeric nanoparticle was prepared and used to track NP uptake into Huh7.5, human hepatoma cells transfected with replicating HCV genomes, compared with non-transfected cells as a model representing hepatocyte uptake. Confocal microscopy and flow cytometry of virus transfected Huh7.5 cells unexpectedly demonstrated two-fold increase in uptake of NP compared to non-transfected cells. Therefore, virus transfection enhanced NP uptake into Huh7.5 cells and NP could be considered as a promising delivery system for targeted treatment of hepatitis viruses.