Polyester nanomedicines targeting inflammatory signaling pathways for cancer therapy.

The growth of cancerous cells and their responses towards substantial therapeutics are primarily controlled by inflammations (acute and chronic) and inflammation-associated products, which either endorse or repress tumor progression. Additionally, major signaling pathways, including NF-κB, STAT3, inflammation-causing factors (cytokines, TNF-α, chemokines), and growth-regulating factors (VEGF, TGF-ß), are vital regulators responsible for the instigation and resolution of inflammations. Moreover, the conventional chemotherapeutics have exhibited diverse limitations, including poor pharmacokinetics, unfavorable chemical properties, poor targetability to the disease-specific disease leading to toxicity; thus, their applications are restricted in inflammation-mediated cancer therapy. Furthermore, nanotechnology has demonstrated potential benefits over conventional chemotherapeutics, such as it protected the incorporated drug/bioactive moiety from enzymatic degradation within the systemic circulation, improving the physicochemical properties of poorly aqueous soluble chemotherapeutic agents, and enhancing their targetability in specified carcinogenic cells rather than accumulating in the healthy cells, leading reduced cytotoxicity. Among diverse nanomaterials, polyester-based nanoparticulate delivery systems have been extensively used to target various inflammation-mediated cancers. This review summarizes the therapeutic potentials of various polyester nanomaterials (PLGA, PCL, PLA, PHA, and others)-based delivery systems targeting multiple signaling pathways related to inflammation-mediated cancer.

A novel liquid chromatography/tandem mass spectrometry (LC-MS/MS) based bioanalytical method for quantification of ethyl esters of Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA) and its application in pharmacokinetic study.

Omega-3 fatty acids are clinically useful and the two marine omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are prevalent in fish and fish oils. Omega-3 fatty acid formulations should undergo a rigorous regulatory step in order to obtain United States Food and Drug Administration (USFDA) approval as prescription drug. In connection with that, despite quantifying EPA and DHA fatty acids, there is a need for quantifying the level of ethyl esters of them in biological samples. In this study, we make use of reverse phase high performance liquid chromatography coupled with mass spectrometry (RP-HPLC-MS)technique for the method development. Here, we have developed a novel multiple reaction monitoring method along with optimized parameters for quantification of EPA and DHA as ethyl esters. Additionally, we attempted to validate the bio-analytical method by conducting the sensitivity, selectivity, precision accuracy batch, carryover test and matrix stability experiments. Furthermore, we also implemented our validated method for evaluation of pharmacokinetics of omega fatty acid ethyl ester formulations.

In vivo in silico pharmacokinetic simulation studies of carvedilol-loaded nanocapsules using GastroPlus.

BACKGROUND: The study aimed at in vivo pharmacokinetic evaluation of carvedilol loaded nanocapsules (CLN) followed by in silico predictions and establishment of IVIVC. METHOD: LC/MS-MS method was developed and validated to estimate the pharmacokinetic profile of CLN. The in silico and IVIVC were established using GastroPlus. RESULTS: The CLN demonstrated 221.09% increase in bioavailability of carvedilol over aqueous suspension. The simulation of plasma concentration profile of CLN exhibited a sensible level of superimposition. The regional absorption of the CLN showed maximum absorption from duodenum and jejunum. The Wagner-Nelson method was found to be most suitable deconvolution method for establishing the IVIVC of CLN. CONCLUSION: The study demonstrated CLN as efficient delivery system to ferry carvedilol with improved bioavailability.

Controlled porosity solubility modulated osmotic pump tablets of gliclazide.

A system that can deliver drug at a controlled rate is very important for the treatment of various chronic diseases such as diabetes, asthma, and heart disease. Poorly water-soluble drug with pH-dependent solubility such as gliclazide (GLZ) offers challenges in the controlled-release formulation because of low dissolution rate and poor bioavailability. Solid dispersion (SD) of GLZ consisted of hydroxypropyl cellulose (HPC-SSL) as a polymeric solubilizer was manufactured by hot melt extrusion (HME) technology. Then, controlled porosity osmotic pump (CPOP) tablet of gliclazide was designed to deliver drug in a controlled manner up to 16 h. The developed formulation was optimized for type and level of pore former and coating weight gain. The optimized formulation was found to exhibit zero order kinetics independent of pH and agitation speed but depends on osmotic pressure of dissolution media indicated that mechanism of drug release was osmotic pressure. The in vivo performance prediction of developed formulation using convolution approach revealed that the developed formulation was superior to the existing marketed extended-release formulation in terms of attaining steady state plasma levels and indicated adequate exposure in translating hypoglycemic response. The prototype solubilization method combined with controlled porosity osmotic pump based technique could provide a unique way to increase dissolution rate and bioavailability of many poorly water-soluble, narrow therapeutic index drugs used in diabetes, cardiovascular diseases, etc.

Coating doxorubicin-loaded nanocapsules with alginate enhances therapeutic efficacy against Leishmania in hamsters by inducing Th1-type immune responses.

BACKGROUND AND PURPOSE: The aim of the present study was to evaluate the immunomodulatory and chemotherapeutic potential of alginate-(SA) coated nanocapsule (NCs) loaded with doxorubicin (SA-NCs-DOX) against visceral leishmaniasis in comparison with nano-emulsions containing doxorubicin (NE-DOX). EXPERIMENTAL APPROACH: NE-DOX was prepared using low-energy emulsification methods. Stepwise addition of protamine sulphate and SA in a layer-by-layer manner was used to form SA-NCs-DOX. SA-NCs-DOX, NE-DOX and Free DOX were compared for their cytotoxicity against Leishmania donovani-infected macrophages in vitro and generation of T-cell responses in infected hamsters in vivo. KEY RESULTS: Size and ζ potential of the NE-DOX and SA-NCs-DOX formulations were 310 ± 2.1 nm and (-)32.6 ± 2.1 mV, 342 ± 4.1 nm and (-)29.3 ± 1.2 mV respectively. SA-NCs-DOX was better (1.5 times) taken up by J774A.1 macrophages compared with NE-DOX. SA-NCs -DOX showed greater efficacy than NE-DOX against intramacrophagic amastigotes. SA-NCs-DOX treatment exhibited enhanced apoptotic efficiency than NE-DOX and free DOX as evident by cell cycle analysis, decrease in mitochondrial membrane potential, ROS and NO production. T-cell responses, when assessed through lymphoproliferative responses, NO production along with enhanced levels of iNOS, TNF-α, IFN-γ and IL-12 were found to be up-regulated after SA-NCs-DOX, compared with responses to NE-DOX in vivo. Parasitic burden was decreased in Leishmania-infected hamsters treated with SA-NCs-DOX, compared with NE-DOX. CONCLUSIONS AND IMPLICATIONS: Our results provide insights into the development of an alternative approach to improved management of leishmaniasis through a combination of chemotherapy with stimulation of the innate immune system.

Development of nanocapsules bearing doxorubicin for macrophage targeting through the phosphatidylserine ligand: a system for intervention in visceral leishmaniasis.

OBJECTIVES: The purpose of this study was to explore the applicability, targeting potential and drug delivery to specialized phagocytes via phosphatidylserine (PS)-specific ligand-anchored nanocapsules (NCs) bearing doxorubicin. METHODS: The layer-by-layer method was utilized to prepare NCs having a nanoemulsion core loaded with doxorubicin (NCs-DOX), which was further grafted with PS. PS-coated NCs (PS-NCs-DOX) were compared with NCs-DOX for in vitro targeting ability by studying uptake by macrophages, intracellular localization, in vivo pharmacokinetics and organ distribution studies. The in vivo antileishmanial activity of free doxorubicin, NCs-DOX and PS-NCs-DOX was tested against visceral leishmaniasis in Leishmania donovani-infected hamsters. RESULTS: Flow cytometric data revealed 1.75-fold enhanced uptake of PS-NCs-DOX in J774A.1 macrophage cell lines compared with NCs-DOX. In vivo organ distribution studies in Wistar rats demonstrated a significantly higher extent of accumulation of PS-NCs-DOX compared with NCs-DOX in macrophage-rich organs, particularly in liver and spleen. Highly significant antileishmanial activity (P < 0.05 compared with NCs) was observed with PS-NCs-DOX, causing 85.23% ±â€Š4.49% inhibition of splenic parasitic burden. NCs-DOX and free doxorubicin caused only 72.88% ±â€Š3.87% and 42.85% ±â€Š2.11% parasite inhibition, respectively, in Leishmania-infected hamsters (P < 0.01 for PS-NCs-DOX versus free doxorubicin and NCs-DOX versus free doxorubicin). CONCLUSIONS: We conclude that the PS targeting moiety can provide a new insight for efficient drug delivery to specialized macrophages and thus may be developed for effective use in macrophage-specific delivery systems, especially for leishmaniasis.

Protective effect of fruits of Morinda citrifolia L. on scopolamine induced memory impairment in mice: a behavioral, biochemical and cerebral blood flow study.

ETHNOPHARMACOLOGICAL RELEVANCE: Noni (Morinda citrifolia L.) is widely used for different illnesses including CNS disorders. Recently Noni has been reported to prevent amyloid beta induced memory impairment in mice. However, the influence of Noni on cholinergic system has not been explored so far. Therefore, present study was designed to investigate effect of Noni fruit on memory, cerebral blood flow (CBF), oxidative stress and acetylcholinesterase (AChE) activity in scopolamine induced amnesia model. MATERIALS AND METHODS: Mice were orally treated with ethanolic extract of Noni fruit and chloroform, ethyl acetate and butanol fractions of ethanolic extract for three days. Scopolamine was administered 5 min prior to acquisition trial and memory function was evaluated by passive avoidance test. CBF was measured by laser doppler flowmetry. AChE activity and oxidative stress parameters were estimated in mice brain at the end of behavioral studies. Further, effect of ethanolic extract and its fractions (5-400 µg/ml) on AChE activity was measured in vitro. RESULTS: Scopolamine caused memory impairment along with reduced CBF, increased AChE activity and oxidative stress in mice brain. Ethanolic extract of Noni fruits and its chloroform and ethyl acetate fractions significantly improved memory and CBF. However, butanol fraction had no effect. Further, increased oxidative stress and AChE activity following scopolamine was significantly attenuated by ethanolic extract of Noni and its fractions. Moreover ethanolic extract and its fractions showed dose dependent inhibition of AChE activity in vitro. CONCLUSION: These observations suggest that Noni may be useful in memory impairment due to its effect on CBF, AChE and oxidative stress.

Hypolipidemic and antihyperlipidemic effects from an aqueous extract of Pachyptera hymenaea (DC.) leaves in rats.

Hypolipidemic and antihyperlipidemic effect from an aqueous extract Pachyptera hymenaea were studied and volatile constituents from the extract were analysed by GC-MS. Extract was administered to normal and diet-induced hypercholestrolemic rats for 28days and serum lipid profiles were estimated. An oral dose, at 200mg/kg/day, resulted in significant declines in plasma LDL-cholesterol, triglycerides (TG) and total cholesterol (TC) by 44.0%, 27.9% and 28.1% respectively, compared to normal rats. An extract at 400mg/kg/day, to hypercholestremic rats, resulted in significant declines in plasma TC, LDL-cholesterol and TG, by 66.1%, 60.0% and 57.6% respectively, compared to a hypercholestremic control. GC-MS study of the volatile oil revealed the presence of two main organosulphur compounds, diallyldisulphide (65.9%, v/v) and diallyltrisulphide (29.6%, v/v). Evidently the extract possesses pronounced hypolipidemic and antihyperlipidemic effects which are comparable to those of atorvastatin. These effects are due to the presence of organosulphur compounds, flavonoids and polyphenols present in the extract.

Simple, economical, and reproducible LC-MS method for the determination of amoxicillin in human plasma and its application to a pharmacokinetic study.

A simple, economical, and reproducible high-performance liquid chromatography mass spectrometric (MS) method is developed and validated for the determination of amoxicillin in human plasma. The present method has been successfully used to determine bioequivalence between a test and innovator formulation of amoxicillin 500 mg capsules. The method is validated in terms of selectivity, precision/accuracy, recovery, dilution integrity, matrix effect, effect of anti-coagulant, and stability studies. Sample preparation is carried out by solid-phase extraction (HLB Oasis cartridges). The processed sample is chromatographed on Hypersil Gold (4.6 x 50 mm); 3 microm C18 column, using 10mM ammonium formate buffer (pH 5.0) and acetonitrile, (10:90, v/v) as mobile phase. Amoxicillin is detected by MS-MS detection with turbo-ion spray in positive ion mode. The weighed (1/X2) calibration curves were linear over the range of 0.17 to 17.0 microg/mL. The intra day precision is from 1.3% to 8.8% and intra day accuracy is 94.1% to 108.5%. The inter day precision is from 1.8% to 6.2% and inter-day accuracy is 95.1% to 105.9%. Mean recovery of 66.3% is observed for amoxicillin and 71.6% for internal standard (ampicillin). The stability of amoxicillin is studied at -15 degrees C and -50 degrees C using human plasma with different anti-coagulants (citrate, monobasic sodium phosphate, dextrose, and adenine-citrate, monobasic sodium phosphate, dextrose, and adenine and ethylene diamine tetraacetic acid-ethylene diamine tetraacetic acid). No significant degradation is observed for 60 days.

Transdermal delivery of propranolol using mixed grades of Eudragit: design and in vitro and in vivo evaluation.

A matrix-dispersion-type transdermal drug delivery system of propranol was developed using different ratios of mixed polymeric grades of Eudragit. Formulations were evaluated for in vitro dissolution characteristics using a Cygnus' sandwich patch holder. Selected formulations followed zero-order release kinetics. In vivo evaluation was carried out on healthy human volunteers following a balanced incomplete block design (BIBD). In vitro dissolution rate constant k and pharmacokinetic parameters generated from plasma and urine were evaluated statistically. Statistically excellent correlation was found between percentages of drug absorbed from patch versus Cmax, AUC0-24, and AUC0-alpha. A highly significant difference was observed when Cmax and AUC0-alpha generated from plasma and urine data were compared, but when ke, t1/2e, ka, and t1/2a were compared, the difference was not significant. Urinary excretion data are suggested as a simpler alternative to blood-level data in studying the kinetics of absorption and deriving the absorption parameter.

Controlled transdermal delivery of propranolol using HPMC matrices: design and in-vitro and in-vivo evaluation.

To improve bioavailability and achieve a smoother plasma-concentration profile as compared with oral administration, a matrix-dispersion-type transdermal delivery system was designed and developed for propranolol using different ratios of hydroxypropylmethylcellulose (HPMC) K4M, K15M and K100M. Formulations were evaluated for in-vitro dissolution characteristics using a Cygnus' sandwich-patch holder. Drug release followed Higuchi rather than zero-order or first-order kinetics. In-vivo evaluation was carried out on healthy volunteers (21+/-1.41 years; 60.89+/-5.35 kg) following the balanced incomplete block design. The dissolution rate constant (k) and data generated from plasma and urine (Cmax, maximum plasma concentration; t(max), time to reach peak plasma concentration; AUC, area under the curve; k(e), elimination rate constant; t1/2e, elimination half-life; k(a), absorption rate constant; t1/2a, absorption half-life) were evaluated statistically by two-way analysis of variance. Statistically excellent correlation was found between the percentage of drug absorbed and Cmax, AUC0-24 and AUC0-infinity. A highly significant difference (P < 0.001) was observed when Cmax and AUC0-infinity, generated from plasma and urine were compared, but k(e), t1/2e, k(a) and t1/2a did not differ significantly (P > 0.1). We conclude that urinary excretion data may be used as a simpler alternative to blood level data in studying the kinetics of absorption and deriving the absorption parameters.

Further studies on chemical evaluation of lauha bhasma iii.

Samples of marketed Lauha bhasma from different manufactures were evaluated chemically. Apart from the 81 -85% iron content, the 15-19% other constituents were determined therein. Ferrous ferric and total iron in a single aliquot were determined spectrophotometrically, Qualitative and chromatographic analysis indicate the presence of sodium, potassium, calcium copper and cobalt in the samples, silicious matter and traces of ascorbic acid were present while tannin was absent in Lauha bhasma . Quantitatively sodium and potassium were determined by flame spectrometry. Upon fractionation, water soluble and acid soluble contents were determined.

In vitro evaluation of some ayurvedic antacids.

The ayurvedic proprietary antacid preparations available in the Indian market were analysed for their antacid activity and compared with allopathic antacid preparations. This study urges the need for standardization of antacid products with in vitro  parameters.

Standardization and bioavailabililty of ayurvedic drug lauha bhasma part-1 physical and chemical evaluation.

Lauha Bhasma, an ayurvedic drug, is widely used in iron deficiency anaemia, this ancient drug is claimed to be better absorbed gastrointestinally, and is also claimed to be devoid of the usual side effects associated with administration of the allopathic iron preparations, Physical and chemical methods of standardization required for any quality preparation, is not found in the ayurvedic and the modern literatures for Lauha Bhasma. Thus an approach has been made to standardize Lauha Bhasma. For the purpose of analysis, samples of all the three commonly available variants of Lauha Bhasma were considered. Qualitative analysis indicates the presence of iron both in the ferric and the ferrous forms, A simple spectrophotometric method has been used for simultaneous determination of ferric ferrous and the total iron content in a single aliquot.

Standardization and bioavailability of ayurvedic drug lauha bhasma- part -ii comparative bioavailability studies.

After analyzing the Lauha Bhasma samples qualitatively and quantitatively, in-vivo studies on healthy adult male rabbits were carried out. Randomly selected anaemic rabbits were divided into different groups and three variants of Lauha Bhasma and ferrous sulphate sample were administered to each group. The effect of each formulation was monitored by measuring the haemoglobin (Hb) content spectrophotometrically (cyanomethaemoglobin method). Increase in the haemoglobin content was found to be significant in case of the ayurvedic formulations as compared to the ferrous sulphate sample.

Selection for vancomycin resistance in clinical isolates of Staphylococcus haemolyticus.

Killing curves were used to characterize Staphylococcus haemolyticus isolates previously reported to contain subpopulations showing increased resistance to vancomycin. Results suggested that vancomycin and teicoplanin were ineffective at a concentration of 8 micrograms/ml and growth was seen between 24 and 48 h. Conversely, the lipopeptide antibiotic daptomycin at the same concentration rapidly killed tested strains by 6 h. Various staphylococcal strains were examined to determine if vancomycin resistance could be selected in all strains of staphylococci, was specie(s) restricted, or was unique to this patient's clinical isolates. About 1 x 10(8) colony-forming units were added to melted brain-heart infusion agar plates containing 12 micrograms/ml of vancomycin. Plates were examined after 48 h for presence of resistant clones. Results indicated that selection for vancomycin resistance was restricted to S. haemolyticus strains. Further, all S. haemolyticus isolates that displayed a double zone of growth around imipenem agar diffusion discs (Impdz) contained stably resistant subpopulations. Vancomycin resistance could not be selected in imipenem-sensitive derivative clones. Impdz isolates that were recovered from geographically distinct locations displayed nearly identical SDS-PAGE protein profiles. It appears that a characteristic susceptibility pattern displayed by clinical isolates of S. haemolyticus may provide a marker for those strains that contain subpopulations having increased resistance to vancomycin.