Priya Ranjan Prasad Verma

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−∞. A highly significant difference was observed when Cmax and AUC0− generated from plasma and urine data were compared, but when ke, t1/2e, ka, t1/2awere 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.

Glibenclamide-loaded self-nanoemulsifying drug delivery system: development and characterization

Objective: To develop and characterize self-nanoemulsifying drug delivery system (SNEDDS) of the poorly water-soluble drug, glibenclamide (GBD). Methods: Solubility of GBD was determined in various vehicles. Phase diagrams were constructed to identify efficient self-emulsification region using oils, surfactants, and cosurfactants in aqueous environment. Formulations were assessed for drug content, spectroscopic clarity, emulsification time, contact angle, zeta potential, particle size, and dissolution studies. On the basis of similarity and dissimilarity of particle size distribution, formulations were further characterized using principal component analysis and agglomerative hierarchy cluster analysis. Results: Among the formulations prepared and evaluated, optimized formulation showed mean particle size between 15.65 and 32.70 nm after 24 hour postdilution in various media. Dilution volume had no significant effect on particle size. Transmission electron microscopy of these formulations confirmed the spherical shape of globules with no signs of coalescence of globules and precipitation of drug. The relevance of difference in t50% and percent dissolution efficiency were evaluated statistically by two-way ANOVA. Infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction studies indicated compatibility between drug, oil, and surfactants. Conclusions: The results of this study indicate that the self-nanoemulsifying drug delivery system of GBD, owing to nanosize, has potential to enhance its absorption and without interaction or incompatibility between the ingredients.

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.

Development and characterization of a lovastatin-loaded self-microemulsifying drug delivery system

The objective of the work was to develop, optimize and evaluate a self-microemulsifying drug delivery system of the poorly water soluble drug, lovastatin. Solubility of lovastatin was determined in various vehicles. Ternary phase diagrams were constructed to identify the efficient self-emulsification region using oils, surfactants, and co-surfactants in aqueous environment. Optimized formulations were assessed for drug content, spectroscopic clarity, emulsification time, contact angle, zeta potential, particle size and dissolution studies. Zeta potential was measured in absence and presence of oleylamine, a positive charge inducer. On the basis of similarity and dissimilarity of particle size distribution, formulations were characterized using principal component analysis and agglomerative hierarchy cluster analysis, the multivariate statistical analysis. Transmission electron microscopy of selected formulations (F5–F7) confirmed the spherical shape of globules with no signs of coalescence of globules and precipitation of drug, even after 24 h post dilution in distilled water. The relevance of differences in t50% and percentage dissolution efficiency was evaluated statistically by two-way ANOVA. Infrared spectroscopy, differential scanning calorimetric and x-ray diffraction studies indicated no incompatibility between drug, oil and surfactants. The results of this study indicate that the self-microemulsifying drug delivery system of lovastatin, owing to nanosize, has potential to enhance its absorption and without interaction or incompatibility between the ingredients.

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% ± 4.49% inhibition of splenic parasitic burden. NCs-DOX and free doxorubicin caused only 72.88% ± 3.87% and 42.85% ± 2.11% 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.

Formulation by design of felodipine loaded liquid and solid self nanoemulsifying drug delivery systems using Box–Behnken design

Abstract Objective: To design and develop liquid and solid self-nanoemulsifying drug delivery systems (SNEDDS and S-SNEDDS) of felodipine (FLD) using Box–Behnken design (BBD). Methods: Solubility study was carried out in various vehicles. Ternary phase diagram was constructed to delineate the boundaries of the nanoemulsion domain. The content of formulation variables, X1 (Acconon E), X2 (Cremophor EL) and X3 (Lutrol E300) were optimized by assessment of 15 formulations (as per BBD) for mean globule sizes in Millipore water (Y1), 0.1 N HCl (Y2), phosphate buffer (pH 6.4) (Y3); emulsification time (Y4) and T85% (Y5). The responses (Y1–Y5) were evaluated statistically by analysis of variance and response surface plots to obtain optimum points. The optimized formulations were solidified by adsorption to solid carrier technique using Aerosil 200 (AER). Results and discussion: Transmission electron microscopy images confirmed the spherical shape of globules with the size range concordant with the globule size analysis by dynamic light scattering technique (<60 nm). The surface morphology of S-SNEDDS (before release) by scanning electron microscopy and atomic force microscopy indicated that SNEDDS are adsorbed uniformly on the surface of AER. The dried residue of S-SNEDDS (after release) revealed the presence of nanometric pores vacated by the previously adsorbed SNEDDS onto AER. Differential scanning calorimetry and X-ray powder diffraction studies illustrated the change of FLD from crystalline to amorphous state. Conclusion: This study indicates that owing to nanosize, SNEDDS and S-SNEDDS of FLD have potential to enhance its absorption and may serve an efficient oral delivery.

Partial biodistribution and pharmacokinetics of isoniazid and rifabutin following pulmonary delivery of inhalable microparticles to Rhesus macaques

Dry powder inhalations (DPI) of microparticles containing isoniazid (INH) and rifabutin (RFB) are under preclinical development for use in pulmonary tuberculosis. Microparticles containing 0.25, 2.5, or 25 mg of each drug were administered daily for 90 days to rhesus macaques (n = 4/group). Single inhalations or intravenous (i.v.) doses were administered to separate groups. Drugs in serum, alveolar macrophages, and organ homogenates were assayed by high-performance liquid chromatography (HPLC). The RFB/INH in the lungs (101.10 ± 12.90/101.07 ± 8.09 μg/g of tissue) was twice that of the liver concentrations (60.22 ± 04.97/52.08 ± 4.62 μg/g) and four times that of the kidneys (22.89 ± 05.22/30.25 ± 3.71 μg/g). Pharmacokinetic parameters indicated the operation of flip-flop kinetics. Thus, the elimination half-life (t(1/2)) of RFB and INH was calculated as 8.01 ± 0.5 and 2.49 ± 0.23 h, respectively, upon intravenous (iv) administration, and as 13.8 ± 0.8 and 10.43 ± 0.77 h following a single inhalation; or 13.36 ± 3.51 and 10.13 ± 3.01 at a presumed steady state (day 60 of dosing). Targeted and sustained drug delivery to nonhuman primate lungs and alveolar macrophages was demonstrated. Flip-flop serum pharmacokinetics was observed, and nonlinearity in some pharmacokinetic parameters at logarithmic dose increments was indicated. The results suggest that human patients would benefit through improvement in biodistribution following DPI.

Development of matrix controlled transdermal delivery systems of pentazocine: In vitro/in vivo performance

Development of matrix controlled transdermal delivery systems of pentazocine: In vitro/in vivo performance The present study aimed to develop hydroxypropyl methylcellulose based transdermal delivery of pentazocine. In formulations containing lower proportions of polymer, the drug released followed the Higuchi kinetics while, with an increase in polymer content, it followed the zero-order release kinetics. Release exponent (n) values imply that the release of pentazocine from matrices was non-Fickian. FT-IR, DSC and XRD studies indicated no interaction between drug and polymer. The in vitro dissolution rate constant, dissolution half-life and pharmacokinetic parameters (Cmax, tmax, AUC(s), t1/2, Kel, and MRT) were evaluated statistically by two-way ANOVA. A significant difference was observed between but not within the tested products. Statistically, a good correlation was found between per cent of drug absorbed from patches vs. Cmax and AUC(s). A good correlation was also observed when per cent drug released was correlated with the blood drug concentration obtained at the same time point. The results of this study indicate that the polymeric matrix films of pentazocine hold potential for transdermal drug delivery. Razvoj matriksnih sustava za transdermalnu isporuku pentazocina: In vitro/in vivo ispitivanje U radu je opisan razvoj transdermalnih sustava na bazi hidroksipropil metilceluloze za isporuku pentazocina. U pripravcima koji sadrže manje udjele polimera, otpuštanje lijeka slijedilo je Higuchijevu kinetiku. Međutim, ako je udio polimera veći oslobađanje je najbolje odgovaralo kinetici nultog reda. Vrijednost eksponenta n implicira da oslobađanje pentazocina iz matriksa nije po Fickovom zakonu. FT-IR, DSC i XRD studije ukazuju da nema interakcije između ljekovite tvari i polimera. In vitro konstanta oslobađanja, poluvrijeme oslobađanja i farmakokinetički parametri (Cmax, tmax, AUC(s), t1/2, Kel, i MRT) procijenjeni su statistički koristeći ANOVA program. Značajna razlika primijećena je između, ali ne i unutar testiranih pripravaka. Pronađena je dobra korelacija između lijeka apsorbiranog iz flastera i Cmax i AUC(s) te oslobođenog lijeka i koncentracije lijeka u krvi. Rezultati ukazuju da su polimerni matriksni filmovi pentazocina potencijalno dobri sustavi za transdermalnu primjenu lijeka.

Ameliorative effect of Noni fruit extract on streptozotocin-induced memory impairment in mice.

This study evaluated the effects of a standardized ethyl acetate extract of Morinda citrifolia L. (Noni) fruit on impairment of memory, brain energy metabolism, and cholinergic function in intracerebral streptozotocin (STZ)-treated mice. STZ (0.5 mg/kg) was administered twice at an interval of 48 h. Noni (50 and 100 mg/kg, postoperatively) was administered for 21 days following STZ administration. Memory function was evaluated using Morris Water Maze and passive avoidance tests, and brain levels of cholinergic function, oxidative stress, energy metabolism, and brain-derived neurotrophic factor (BDNF) were estimated. STZ caused memory impairment in Morris Water Maze and passive avoidance tests along with reduced brain levels of ATP, BDNF, and acetylcholine and increased acetylcholinesterase activity and oxidative stress. Treatment with Noni extract (100 mg/kg) prevented the STZ-induced memory impairment in both behavioral tests along with reduced oxidative stress and acetylcholinesterase activity, and increased brain levels of BDNF, acetylcholine, and ATP level. The study shows the beneficial effects of Noni fruit against STZ-induced memory impairment, which may be attributed to improved brain energy metabolism, cholinergic neurotransmission, BDNF, and antioxidative action.

Inhalable microparticles containing nitric oxide donors: saying NO to intracellular Mycobacterium tuberculosis.

Although nitric oxide (NO) is a bactericidal component of the macrophages innate response to intracellular infections such as tuberculosis (TB), prolonged inhalation of NO gas has little benefit in chemotherapy of TB. The impact of controlled release of NO through intracellular delivery of NO donors to macrophages infected in vitro with Mycobacterium tuberculosis (Mtb) was investigated. Inhalable microparticles (MP) were prepared by spray-drying. Isosorbide mononitrate (ISMN), sodium nitroprusside (SNP), and diethylenetriamine nitric oxide adduct (DETA/NO) were incorporated in poly(lactic-co-glycolic acid) (PLGA) with encapsulation efficiencies of >90% to obtain MP yields of ∼70%. The mass median aerodynamic diameter (MMAD) of the MP was 2.2-2.4 μm within geometric standard deviations (GSD) of ≤0.1 μm. MP were phagocytosed by THP-1 derived macrophages in culture and significantly (P < 0.05) sustained NO secretion into culture supernatant from 6 to 72 h in comparison to equivalent amounts of drugs in solution. Significantly (P < 0.05) higher dose-dependent killing of intracellular Mtb by MP compared to equivalent amounts of drugs in solution was observed on estimation of colony forming units (CFU) surviving 24 h after exposure to drugs or MP. The cytotoxicity of MP toward macrophages was lower than that of dissolved drugs. It was concluded that inhalable MP can target NO donors to the macrophage, control NO release in the macrophage cytosol, and reduce Mtb CFU by up to 3-log in 24 h, at doses that are much lower than those required for cardiovascular effects.