Formulation, Optimization, and Evaluation of Moringa oleifera Leaf Polyphenol-Loaded Phytosome Delivery System against Breast Cancer Cell Lines.

Moringa oleifera leaf polyphenols (Mopp) were encapsulated with phytosomes to enhance their efficacy on 4T1 cancer cell lines. The Mopp were extracted via microwave-assisted extraction. Moringa oleifera polyphenol-loaded phytosomes (MoP) were prepared with the nanoprecipitation method and characterized using the dynamic light scattering and dialysis membrane techniques. The in vitro cytotoxic and antiproliferative activity were investigated with the (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazole) MTT assay. Acute toxicity was assessed using Swiss albino mice. An MoP particle size of 296 ± 0.29 nm, −40.1 ± 1.19 mV zeta potential, and polydispersity index of 0.106 ± 0.002 were obtained. The total phenolic content was 50.81 ± 0.02 mg GAE/g, while encapsulation efficiency was 90.32 ± 0.11%. The drug release profiles demonstrated biphasic and prolonged subsequent sustained release. In vitro assays indicated MoP had a low cytotoxicity effect of 98.84 ± 0.53 µg/mL, doxorubicin was 68.35 ± 3.508, and Mopp was 212.9 ± 1.30 µg/mL. Moreover, MoP exhibited the highest antiproliferative effect on 4T1 cancer cells with an inhibitory concentration of 7.73 ± 2.87 µg/mL and selectivity index > 3. The results indicated a significant difference (p ≤ 0.001) in MoP when compared to Mopp and doxorubicin. The in vivo investigation showed the safety of MoP at a dose below 2000 mg/kg. The present findings suggest that MoP may serve as an effective and promising formulation for breast cancer drug delivery and therapy.

Relaxed complex scheme and molecular dynamics simulation suggests small molecule inhibitor of human TMPRSS2 for combating COVID-19.

As the coronavirus disease 19 (COVID-19) pandemic continues to pose a health and economic crisis worldwide, the quest for drugs and/or vaccines against the virus continues. The human transmembrane protease serine 2 (TMPRSS2) has attracted attention as a target for drug discovery, as inhibition of its catalytic reaction would result in the inactivation of the proteolytic cleavage of the SARS-CoV-2 S protein. As a result, the inactivation prevents viral cell entry to the host's cell. In this work, we screened and identified two potent molecules that interact and inhibit the catalytic reaction by using computational approaches. Two docking screening experiments were performed utilizing the crystal structure and holo ensemble structure obtained from molecular dynamics in bound form. There is enhancement and sensitivity of docking results to the holo ensemble as compared to the crystal structure. Compound 1 demonstrated a similar inhibition value to nafamostat by interacting with catalytic triad residues His296 and Ser441, thereby disrupting the already established hydrogen bond interaction. The stability of the ligand-TMPRSS2 complexes was studied by molecular dynamics simulation, and the binding energy was re-scored by using molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) binding free energy. The obtained compounds may serve as an initial point toward the discovery of potent TMPRSS2 inhibitors upon further in vivo validation.Communicated by Ramaswamy H. Sarma.

Luteolin: a blocker of SARS-CoV-2 cell entry based on relaxed complex scheme, molecular dynamics simulation, and metadynamics.

Natural products have served human life as medications for centuries. During the outbreak of COVID-19, a number of naturally derived compounds and extracts have been tested or used as potential remedies against COVID-19. Tetradenia riparia extract is one of the plant extracts that have been deployed and claimed to manage and control COVID-19 by some communities in Tanzania and other African countries. The active compounds isolated from T. riparia are known to possess various biological properties including antimalarial and antiviral. However, the underlying mechanism of the active compounds against SARS-CoV-2 remains unknown. Results in the present work have been interpreted from the view point of computational methods including molecular dynamics, free energy methods, and metadynamics to establish the related mechanism of action. Among the constituents of T. riparia studied, luteolin inhibited viral cell entry and was thermodynamically stable. The title compound exhibit residence time and unbinding kinetics of 68.86 ms and 0.014 /ms, respectively. The findings suggest that luteolin could be potent blocker of SARS-CoV-2 cell entry. The study shades lights towards identification of bioactive constituents from T. riparia against COVID-19, and thus bioassay can be carried out to further validate such observations.

Solvent effects on host-guest residence time and kinetics: further insights from metadynamics simulation of Toussaintine-A unbiding from chitosan nanoparticle.

Solvents play an important role in host-guest intermolecular interactions. The kinetics and residence time of Toussaintine-A (TouA) unbinding from chitosan was investigated by means of well-tempered metadynamics and thermodynamic integration using two solvents, polar aprotic (DMSO), and polar protic (water). The kinetic rates were found to be strongly dependent on the solvent polarity; hence, the unbinding rate proceeded much faster in DMSO compared to water. DMSO tends to participate less in a chemical reaction by weakening the intermolecular interaction between chitosan and TouA due to lack of acidic hydrogen resulting in a reduction of the transition state. On the other hand, water, which ought to donate hydrogen atoms, sustains a strong interaction and hence large barrier heights. Consequently, this reduces the unbinding rate and increases the residence time. Binding free energy from thermodynamic integration suggests a thermodynamic stable chitosan-TouA complex in water than in DMSO. Graphical abstract.

Ensemble-based screening of natural products and FDA-approved drugs identified potent inhibitors of SARS-CoV-2 that work with two distinct mechanisms.

The recent outbreak of SARS-CoV-2 is responsible for high morbidity and mortality rate across the globe. This requires an urgent identification of drugs and other interventions to overcome this pandemic. Computational drug repurposing represents an alternative approach to provide a more effective approach in search for COVID-19 drugs. Selected natural product known to have antiviral activities were screened, and based on their hits; a similarity search with FDA approved drugs was performed using computational methods. Obtained drugs from similarity search were assessed for their stability and inhibition against SARS-CoV-2 targets. Diosmin (DB08995) was found to be a promising drug that works with two distinct mechanisms, preventing viral replication and viral fusion into the host cell. Isoquercetin (DB12665) and rutin (DB01698) work by inhibiting viral replication and preventing cell entry, respectively. Our analysis based on molecular dynamics simulation and MM-PBSA binding free energy calculation suggests that diosmin, isoquercetin, rutin and other similar flavone glycosides could serve as SARS-CoV-2 inhibitor, hence an alternative solution to treat COVID-19 upon further clinical validation.

Development of a Natural Product Rich in Bioavailable Omega-3 DHA from Locally Available Ingredients for Prevention of Nutrition Related Mental Illnesses.

Objectives: Poor mental health remains a serious public concern worldwide. The most vulnerable individuals are children and adolescents in developing countries. Nutritional deficiency of long-chain omega-3 fatty acids, particularly docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), have long been recognized as a major contributing factor for mental health illnesses. Provision of ready-to-use natural product rich in preformed Omega-3 DHA and EPA could address this problem. However, most commonly used products are expensive and contain less or no preformed Omega-3 DHA and EPA, making them less suitable for prevention of mental illnesses in resource-poor countries. The main objective of this study was to develop a natural product rich in preformed Omega-3 DHA and EPA from locally available ingredients.Methods: Linear programing (LP) was used to formulate a natural product rich in preformed Omega-3 DHA and other essential nutrients using locally available ingredients other than fish and dairy products. Laboratory analysis was then performed to validate the nutritional value of the LP-formulation using standard analytical methods. The relative difference between the LP tool calculated values, and the laboratory-analyzed values were calculated. Sensory testing was also done to evaluate consumer acceptance of the final product.Results: Optimal formulation contained about 220 mg of preformed Omega-3 DHA + EPA, enough to meet the RDI for children aged 2-10 years. The LP analysis further showed that the cost of the developed product is USD 0.15/100 g, which is 50% lower than that of Plumpy'nut. Laboratory analysis revealed similar results as that of LP at P = 0.05.Conclusions: These findings indicate that ready-to-use natural food rich in preformed DHA and EPA can be developed from locally available ingredients.

A computational study on the role of water and conformational fluctuations in Hsp90 in response to inhibitors.

Molecular chaperone Heat Shock Protein 90 (Hsp90) represents an interesting chemotherapeutic target for cancer treatments as it plays a role in cancer proliferation. Thus, continued effort to identify novel inhibitors of this target is an important task. Drug design using computational approach has gained significant attention in recent years. This work aims to propose docking protocols to re-purpose FDA-approved drugs targeting Hsp90. Sensitivity of results to different docking protocols such apo, holo and receptor ensembles (relaxed complex) structures, the role of water and conformational changes of Hsp90, are described. We show that the protein conformation and water have effects on drug binding. Holo relaxed complex receptors ensembles improves the binding energy of ligands to the protein. We also compare and contrast structural stability of three drugs namely: ezetimibe, pitavastatin and vilazodon in the Hsp90 protein. The results obtained serves as a possible basis towards developing Hsp90 inhibitors.

Spray-Dried, Nanoencapsulated, Multi-Drug Anti-Tuberculosis Therapy Aimed at Once Weekly Administration for the Duration of Treatment.

Aiming to improve the treatment outcomes of current daily tuberculosis (TB) chemotherapy over several months, we investigated whether nanoencapsulation of existing drugs would allow decreasing the treatment frequency to weekly, thereby ultimately improving patient compliance. Nanoencapsulation of three first-line anti-TB drugs was achieved by a unique, scalable spray-drying technology forming free-flowing powders in the nanometer range with encapsulation efficiencies of 82, 75, and 62% respectively for rifampicin, pyrazinamide, and isoniazid. In a pre-clinical study on TB infected mice, we demonstrate that the encapsulated drugs, administered once weekly for nine weeks, showed comparable efficacy to daily treatment with free drugs over the same experimental period. Both treatment approaches had equivalent outcomes for resolution of inflammation associated with the infection of lungs and spleens. These results demonstrate how scalable technology could be used to manufacture nanoencapsulated drugs. The formulations may be used to reduce the oral dose frequency from daily to once weekly in order to treat uncomplicated TB.

Larvicidal activity of Hypoestes forskaolii (Vahl) R. Br root extracts against Anopheles gambiae Giless.s, Aedes aegypti L, and Culex quinquefasciatus Say.

Aim: This study aimed to evaluate larvicidal activity of Hypoestes forskaolii R. Br root extract against 3rd instar Anopheles gambiae, Aedes aegypti, and Culex quinquefasciatus. Methods: A protocol developed by the World Health Organization was adopted, with minor modification using chloroform and methanol extracts with concentrations ranging from 25-750 µg/mL. Results: The H. forskaolii chloroform extract exhibited very high larvicidal activity after 72 hours of exposure, with LC50 2.0322, 3.8989, 6.0004 µg/mL against A. gambiae, A. aegypti, and C. quinquefasciatus, respectively. Conclusion: The larvicidal activity of H. forskaolii is reported for the first time in this paper. The effectiveness of H. forskaolii chloroform extract warrants further research to develop botanical mosquito repellants from this source.

Comparative in vitro transportation of pentamidine across the blood-brain barrier using polycaprolactone nanoparticles and phosphatidylcholine liposomes.

Nanoparticles (NPs) have gained importance in addressing drug delivery challenges across biological barriers. Here, we reformulated pentamidine, a drug used to treat Human African Trypanosomiasis (HAT) in polymer based nanoparticles and liposomes and compared their capability to enhance pentamidine penetration across blood brain barrier (BBB). Size, polydispersity index, zeta potential, morphology, pentamidine loading and drug release profiles were determined by various methods. Cytotoxicity was tested against the immortalized mouse brain endothelioma cells over 96 h. Moreover, cells monolayer integrity and transportation ability were examined for 24 h. Pentamidine-loaded polycaprolactone (PCL) nanoparticles had a mean size of 267.58, PDI of 0.25 and zeta potential of -28.1 mV and pentamidine-loaded liposomes had a mean size of 119.61 nm, PDI of 0.25 and zeta potential 11.78. Pentamidine loading was 0.16 µg/mg (w/w) and 0.17 µg/mg (w/w) in PCL NPs and liposomes respectively. PCL nanoparticles and liposomes released 12.13% and 22.21% of pentamidine respectively after 24 h. Liposomes transported 87% of the dose, PCL NPs 66% of the dose and free pentamidine penetration was 63% of the dose. These results suggest that liposomes are comparatively promising nanocarriers for transportation of pentamidine across BBB.

Antimalarial activity of Cucumis metuliferus and Lippia kituiensis against Plasmodium berghei infection in mice.

BACKGROUND: The search for new antimalarial drugs has become progressively urgent due to plasmodial resistance to most of the commercially available antimalarial drugs. As part of this effort, the study evaluated the antimalarial activity of Cucumis metuliferus and Lippia kituiensis, which are traditionally used in Tanzania for the treatment of malaria. MATERIALS AND METHODS: In vivo antimalarial activity was assessed using the 4-day suppressive antimalarial assay. Mice were infected by injecting via tail vein 1×107 erythrocytes infected by Plasmodium berghei ANKA. Extracts were administered orally; chloroquine (10 mg/kg/day) and dimethyl sulfoxide (5 mL/kg/day) were used as positive and negative controls, respectively. The level of parasitemia, survival time, packed cell volume (PCV) and variation in body weight of mice were used to determine the antimalarial activity of the extract. RESULTS: The ethyl acetate, methanolic and chloroform extracts of C. metuliferus and L. kituiensis significantly (p<0.05) inhibited parasitemia in a dose-dependent manner and prevented loss of body weight at the dose levels of 600 mg/kg and 1500 mg/kg, respectively. In addition, the extracts prolonged the mean survival time of P. berghei-infected mice compared to the non-treated control. The plant extracts did not show reduction of PCV except at the low dose of 300 mg/kg. The highest suppression was recorded at the dose level of 1,500 mg/kg. At this dose, C. metuliferus in chloroform, methanolic and ethyl acetate extracts had percentage suppression of 98.55%, 88.89% and 84.39%, respectively, whereas L. kituiensis in ethyl acetate, chloroform and methanolic extracts exhibited suppression of the pathogens of 95.19%, 93.88% and 74.83%, respectively. CONCLUSION: It is worth reporting that the two plants induced suppression which is equivalent to that induced by chloroquine (C. metuliferus chloroform and L. Kituiensis ethyl acetate). The two plants have been demonstrated to be potential sources of antimalarial templates.

Polyamidoamine Dendrimers for Enhanced Solubility of Small Molecules and Other Desirable Properties for Site Specific Delivery: Insights from Experimental and Computational Studies.

Clinical applications of many small molecules are limited due to poor solubility and lack of controlled release besides lack of other desirable properties. Experimental and computational studies have reported on the therapeutic potential of polyamidoamine (PAMAM) dendrimers as solubility enhancers in pre-clinical and clinical settings. Besides formulation strategies, factors such as pH, PAMAM dendrimer generation, PAMAM dendrimer concentration, nature of the PAMAM core, special ligand and surface modifications of PAMAM dendrimer have an influence on drug solubility and other recommendable pharmacological properties. This review, therefore, compiles the recently reported applications of PAMAM dendrimers in pre-clinical and clinical uses as enhancers of solubility and other desirable properties such as sustained and controlled release, bioavailability, bio-distribution, toxicity reduction or enhancement, and targeted delivery of small molecules with emphasis on cancer treatment.

Antimicrobial dependence of silver nanoparticles on surface plasmon resonance bands against Escherichia coli.

This study presents a simple and trouble-free method for determining the antimicrobial properties of silver nanoparticles (AgNPs) based on the surface plasmon resonance (SPR) bands. AgNPs were prepared by chemical reduction method using silver nitrates as a metallic precursor and formaldehyde (HCHO) as a reducing agent and capped by polyethylene glycol. Effects of several processing variables on the size and shape of AgNPs were monitored using an ultraviolet-visible spectrophotometer based on their SPR bands. The formed particles showing various particle shapes and full width at half maximum (FWHM) were tested against Escherichia coli by surface spreading using agar plates containing equal amounts of selected AgNPs samples. The NPs exhibited higher antimicrobial properties; however, monodispersed spherical NPs with narrow FWHM were more effective against E. coli growth. The NPs prepared are promising candidates in diverse applications such as antimicrobial agents in the food and biomedical industries.

Transformation of food packaging from passive to innovative via nanotechnology: concepts and critiques.

In recent decades, there is a global advancement in manufacturing industry due to increased applications of nanotechnology. Food industry also has been tremendously changing from passive packaging to innovative packaging, to cope with global trends, technological advancements, and consumer preferences. Active research is taking place in food industry and other scientific fields to develop innovative packages including smart, intelligent and active food packaging for more effective and efficient packaging materials with balanced environmental issues. However, in food industry the features behind smart packaging are narrowly defined to be distinguished from intelligent packaging as in other scientific fields, where smart materials are under critical investigations. This review presents some scientific concepts and features pertaining innovative food packaging. The review opens new research window in innovative food packaging to cover the existing disparities for further precise research and development of food packaging industry.

Development, characterization and antimalarial efficacy of dihydroartemisinin loaded solid lipid nanoparticles.

Effective use of dihydroartemisinin (DHA) is limited by poor water-solubility, poor pharmacokinetic profile and unsatisfactory clinical outcome especially in monotherapy. To reduce such limitations, we reformulated DHA into solid lipid nanoparticles (SLNs) as a nanomedicine drug delivery system. DHA-SLNs were characterized for physical parameters and evaluated for in vitro and in vivo antimalarial efficacy. DHA-SLNs showed desirable particle characteristics including particle size (240.7 nm), particle surface charge (+17.0 mV), drug loadings (13.9 wt %), encapsulation efficacy (62.3%), polydispersity index (0.16) and a spherical appearance. Storage stability up to 90 days and sustained release of drug over 20 h was achieved. Enhanced in vitro (IC50 0.25 ng/ml) and in vivo (97.24% chemosuppression at 2mg/kg/day) antimalarial activity was observed. Enhancement in efficacy was 24% when compared to free DHA. These encouraging results show potential of using the described formulation for DHA drug delivery for clinical application. FROM THE CLINICAL EDITOR: Malaria still poses a significant problem worldwide. One of the current drugs, artemisinin has been shown to be effective, but has poor water-solubility. The authors here described their formulation of making dihydroartemisinin (DHA) into solid lipid nanoparticles, with subsequent enhancement in efficacy. These results would have massive potential in the clinical setting.

Nanomedicine: Past, present and future - A global perspective.

Nanomedicine is an emerging and rapidly evolving field and includes the use of nanoparticles for diagnosis and therapy of a variety of diseases, as well as in regenerative medicine. In this mini-review, leaders in the field from around the globe provide a personal perspective on the development of nanomedicine. The focus lies on the translation from research to development and the innovation supply chain, as well as the current status of nanomedicine in industry. The role of academic professional societies and the importance of government funding are discussed. Nanomedicine to combat infectious diseases of poverty is highlighted along with other pertinent examples of recent breakthroughs in nanomedicine. Taken together, this review provides a unique and global perspective on the emerging field of nanomedicine.

Mycolic acids, a promising mycobacterial ligand for targeting of nanoencapsulated drugs in tuberculosis.

The appearance of drug-resistant strains of Mycobacterium tuberculosis (Mtb) poses a great challenge to the development of novel treatment programmes to combat tuberculosis. Since innovative nanotechnologies might alleviate the limitations of current therapies, we have designed a new nanoformulation for use as an anti-TB drug delivery system. It consists of incorporating mycobacterial cell wall mycolic acids (MA) as targeting ligands into a drug-encapsulating Poly dl-lactic-co-glycolic acid polymer (PLGA), via a double emulsion solvent evaporation technique. Bone marrow-derived mouse macrophages, either uninfected or infected with different mycobacterial strains (Mycobacterium avium, Mycobacterium bovis BCG or Mtb), were exposed to encapsulated isoniazid-PLGA nanoparticles (NPs) using MA as a targeting ligand. The fate of the NPs was monitored by electron microscopy. Our study showed that i) the inclusion of MA in the nanoformulations resulted in their expression on the outer surface and a significant increase in phagocytic uptake of the NPs; ii) nanoparticle-containing phagosomes were rapidly processed into phagolysosomes, whether MA had been included or not; and iii) nanoparticle-containing phagolysosomes did not fuse with non-matured mycobacterium-containing phagosomes, but fusion events with mycobacterium-containing phagolysosomes were clearly observed.

Curdlan-Conjugated PLGA Nanoparticles Possess Macrophage Stimulant Activity and Drug Delivery Capabilities.

PURPOSE: There is significant interest in the application of nanoparticles to deliver immunostimulatory signals to cells. We hypothesized that curdlan (immune stimulating polymer) could be conjugated to PLGA and nanoparticles from this copolymer would possess immunostimulatory activity, be non-cytotoxic and function as an effective sustained drug release system. METHODS: Carbodiimide chemistry was employed to conjugate curdlan to PLGA. The conjugate (C-PLGA) was characterized using (1)H and (13)C NMR, FTIR, DSC and TGA. Nanoparticles were synthesized using an emulsion-solvent evaporation technique. Immunostimulatory activity was characterized in THP-1 derived macrophages. MTT assay and real-time impedance measurements were used to characterize polymer and nanoparticle toxicity and uptake in macrophages. Drug delivery capability was assessed across Caco-2 cells using rifampicin as a model drug. RESULTS: Spectral characterization confirmed successful synthesis of C-PLGA. C-PLGA nanoparticles enhanced phosphorylated ERK production in macrophages indicating cell stimulation. Nanoparticles provided slow release of rifampicin across Caco-2 cells. Polymers but not nanoparticles altered the adhesion profiles of the macrophages. Impedance measurements suggested Ca(2+) dependent uptake of nanoparticles by the macrophages. CONCLUSIONS: PLGA nanoparticles with macrophage stimulating and sustained drug delivery capabilities have been prepared. These nanoparticles can be used to stimulate macrophages and concurrently deliver drug in infectious disease therapy.

Oral lipid-based nanoformulation of tafenoquine enhanced bioavailability and blood stage antimalarial efficacy and led to a reduction in human red blood cell loss in mice.

Tafenoquine (TQ), a new synthetic analog of primaquine, has relatively poor bioavailability and associated toxicity in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals. A microemulsion formulation of TQ (MTQ) with sizes <20 nm improved the solubility of TQ and enhanced the oral bioavailability from 55% to 99% in healthy mice (area under the curve 0 to infinity: 11,368±1,232 and 23,842±872 min·µmol/L) for reference TQ and MTQ, respectively. Average parasitemia in Plasmodium berghei-infected mice was four- to tenfold lower in the MTQ-treated group. In vitro antiplasmodial activities against chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum indicated no change in half maximal inhibitory concentration, suggesting that the microemulsion did not affect the inherent activity of TQ. In a humanized mouse model of G6PD deficiency, we observed reduction in toxicity of TQ as delivered by MTQ at low but efficacious concentrations of TQ. We hereby report an enhancement in the solubility, bioavailibility, and efficacy of TQ against blood stages of Plasmodium parasites without a corresponding increase in toxicity.