Moghis U. Ahmad

Novel cationic cardiolipin analogue-based liposome for efficient DNA and small interfering RNA delivery in vitro and in vivo

Cationic liposomes have been successfully used as an alternative approach to viral systems to deliver nucleic acids. However, high toxicity and inconsistent transfection efficiency have been associated with the currently available liposomes. Therefore, a novel cationic liposome was developed based on a synthetic cationic cardiolipin analogue (CCLA) to test the DNA transfection efficiency. This CCLA-based liposome was also used to determine the therapeutic efficacy of c-raf small interfering RNA (siRNA) in mice. In this report, we showed that the CCLA-based liposome was less toxic and effectively transfected reporter genes in vitro and in vivo. The transfection efficiency in mice was seven-fold higher than the commercially available DOTAP-based liposome. In addition, c-raf siRNA in the presence of CCLA-based liposome induced up to 62% of growth inhibition in cancer cells. Treatment of c-raf siRNA/CCLA complex in SCID mice bearing human breast xenograft tumors resulted in 73% of tumor growth suppression as compared to free c-raf siRNA group. In conclusion, a novel CCLA-based liposome showed less toxicity and broad usage both in vitro and in vivo with DNA and siRNA.

Photocatalytic, sonocatalytic and sonophotocatalytic degradation of Rhodamine B using ZnO/CNTs composites photocatalysts

A series of ZnO nanoparticles decorated on multi-walled carbon nanotubes (ZnO/CNTs composites) was synthesized using a facile sol method. The intrinsic characteristics of as-prepared nanocomposites were studied using a variety of techniques including powder X-ray diffraction (XRD), high resolution transmission electron microscope (HR-TEM), transmission electron microscope (TEM), scanning electron microscope (SEM) with energy dispersive X-ray analysis (EDX), Brunauer Emmett Teller (BET) surface area analyzer and X-ray photoelectron spectroscopy (XPS). Optical properties studied using UV-Vis diffuse reflectance spectroscopy confirmed that the absorbance of ZnO increased in the visible-light region with the incorporation of CNTs. In this study, degradation of Rhodamine B (RhB) as a dye pollutant was investigated in the presence of pristine ZnO nanoparticles and ZnO/CNTs composites using photocatalysis and sonocatalysis systems separately and simultaneously. The adsorption was found to be an essential factor in the degradation of the dye. The linear transform of the Langmuir isotherm curve was further used to determine the characteristic parameters for ZnO and ZCC-5 samples which were: maximum absorbable dye quantity and adsorption equilibrium constant. The natural sunlight and low power ultrasound were used as an irradiation source. The experimental kinetic data followed the pseudo-first order model in photocatalytic, sonocatalytic and sonophotocatalytic processes but the rate constant of sonophotocatalysis is higher than the sum of it at photocatalysis and sonocatalysis process. The sonophotocatalysis was always faster than the respective individual processes due to the more formation of reactive radicals as well as the increase of the active surface area of ZnO/CNTs photocatalyst. Chemical oxygen demand (COD) of textile wastewater was measured at regular intervals to evaluate the mineralization of wastewater.

Nanosomal Amphotericin B is an efficacious alternative to Ambisome® for fungal therapy.

Amphotericin B was formulated in lipids (Nanosomal Amphotericin B) without using any detergent or toxic organic solvents during the preparation. Electron microscopy and particle size determination of Nanosomal Amphotericin B showed a homogeneous population of nanosized particles below 100 nm. Hemolysis assay indicated that Nanosomal Amphotericin B causes significantly less lysis of red blood cells than Amphotericin B deoxycholate and was comparable to Ambisome. A maximum daily dose of Nanosomal Amphotericin B at 5 mg/kg in rabbits and 10 mg/kg in mice for 28 days showed no symptoms of toxicity, mortality or significant body weight reduction. Hematological and gross pathological analysis of tissues revealed no abnormalities attributable to the drug treatment. Nanosomal Amphotericin B and Ambisome were injected (iv) at 2 mg/kg consecutively for 5 days into mice infected with Aspergillus fumigatus. The treatment resulted in 90% survival with Nanosomal Amphotericin B and only 30% survival with Ambisome after 10 days of fungal infection. However, all of the 10 control mice which were not treated with Amphotericin B died within 5 days of fungal infection. Nanosomal Amphotericin B is safe, cost effective and provides an alternative option for treatment of fungal disease.

Endoxifen is a new potent inhibitor of PKC: A potential therapeutic agent for bipolar disorder

Protein kinase C (PKC) plays a major role in regulation of both pre and postsynaptic neurotransmission. Excessive activation of PKC results in symptoms related to bipolar disorder. Tamoxifen, a widely used breast cancer drug is known to inhibit PKC and demonstrate antimanic properties in human. We describe herein the synthesis of endoxifen, a tamoxifen active metabolite and compared its PKC inhibitory activity with that of tamoxifen. Endoxifen exhibited fourfold higher potency compared to tamoxifen.

Polyoxyl 60 hydrogenated castor oil free nanosomal formulation of immunosuppressant Tacrolimus: Pharmacokinetics, safety, and tolerability in rodents and humans

OBJECTIVE Develop Nanosomal formulation of Tacrolimus to provide safer alternative treatment for organ transplantation patients. Investigate safety, tolerability and pharmacokinetics of Nanosomal Tacrolimus formulation versus marketed Tacrolimus containing polyoxyl 60 hydrogenated castor oil (HCO-60) that causes side effects. METHODS Nanosomal Tacrolimus was prepared in an aqueous system. The particle size was measured by Particle Sizing Systems and structure morphology was determined by freeze-fracture electron microscopy. Investigational safety studies were conducted in mice and rats. Safety and pharmacokinetics of Nanosomal Tacrolimus were also evaluated in healthy human subjects. RESULTS The morphology of Nanosomal Tacrolimus showed a homogeneous population of nanosized particles with mean particle size of less than 100 nm. A 14 day consecutive administration of Nanosomal Tacrolimus up to 5 and 10mg/kg dose in rats and mice respectively, resulted in no mortality. Nanosomal Tacrolimus in human studies showed that it is safe and the pharmacokinetics profile is similar to the marketed HCO-60 based Tacrolimus. No significant change in peripheral blood lymphocyte percentage was noted in either mice or healthy human male subjects. CONCLUSIONS Nanosomal Tacrolimus is well characterized product which provides a new treatment option. It contains no alcohol or surfactants like HCO-60. Thus, Nanosomal Tacrolimus presents a new and improved therapeutic approach for organ transplant patients compared to the marketed HCO-60 based Tacrolimus product.

An efficient and novel method for the synthesis of cardiolipin and its analogs

A novel synthetic method has been developed for cardiolipin and its analog via a chlorophosphoramidite coupling reaction followed by oxidation. The reagent, N,N-diisopropylmethylphosphoramidic chloride, couples effectively with 1,2-O-dimyristoyl-sn-glycerol in the presence of an amidite activator to form a phosphoamidite intermediate, which then reacts with 2-O-benzylglycerol in the presence of a basic catalyst followed by in situ oxidation to give the corresponding protected cardiolipin. Deprotection of the protecting groups provides tetramyristoyl cardiolipin in good overall yield of 60%. The synthetic method is applicable to large-scale synthesis of cardiolipin and various analogs with or without unsaturation for liposomal drug delivery.

Guggullipid derivatives: synthesis and applications

Two guggullipid derivatives, Z-guggulsulfate [4,17(20)-pregnadiene-3-one-16beta-sulfate] sodium salt and Z-guggullaurate [4,17(20)-pregnadiene-3-one-16beta-laurate], have been synthesized and evaluated for liposomal drug delivery system. Its precursor, Z-guggulsterol [4,17(20)-pregnadiene-3-one-16beta-ol], is also synthesized in gram scale starting from guggulsterone using the novel combination of known reactions in fewer steps and with higher yield than previously reported synthesis. These new synthetic guggullipid derivatives were also used in the preparation of liposomes. This new class of lipid molecules will be a useful tool in the development of nanosomal or liposomal drug delivery system.

A short, concise route to diphosphatidylglycerol (cardiolipin) and its variants

A new approach is described for the synthesis of the cardiolipin family of phospholipids that uses phosphonium salt methodology. The method involves the reaction of 2-O-protected glycerol with a trialkyl phosphite derived from 1,2-diacyl-sn-glycerol in the presence of pyridinium bromide perbromide and triethylamine to afford the phosphoric triesters. The synthesis involves three steps and allows the preparation of a wide range of cardiolipins with different substitution patterns and chain lengths, including unsaturated derivatives. The use of inexpensive protecting groups and the ease of purification facilitate this synthetic route and allow its scale-up in a higher overall yield (72%) than the literature methods.

Bioequivalence Study of Pegylated Doxorubicin Hydrochloride Liposome(PEGADRIA) and DOXILî in Ovarian Cancer Patients: PhysicochemicalCharacterization and Pre-clinical Studies

Objective:To develop Pegylated Doxorubicin Hydrochloride Liposome (PEGADRIA) and compare its physicochemical properties, preclinical safety and efficacy, clinical pharmacokinetic and safety profiles with those of the reference product, Doxil®. Methods: PEGADRIA was prepared and the structure morphology, lamellarity, size, shape, drug loading, lipid bilayer and Peg layer thickness were determined. Safety studies were conducted in mice and rats and efficacy study was conducted in a P-388 leukemia mouse model. To evaluate the pharmacokinetic profile of PEGADRIA, a multicenter, open label, balanced, randomized, two-treatment, two-period, two-sequence, single dose cross-over bioequivalence study was conducted with Doxil® in ovarian cancer patients whose disease had progressed or reoccurred after platinum based chemotherapy under fasting conditions. The pharmacokinetic parameters were determined based on the concentration-time profiles of doxorubicin, whereas the concentration was determines using LC-MS/MS methods. Results: PEGADRIA was similar to Doxil® in terms of general morphology, lamellarity, size, shape, drug loading, lipid bilayer and Peg layer thickness. PEGADRIA and Doxil® showed comparable survival benefit in leukemic mice. The toxicity profiles of PEGADRIA in both mice and rats were comparable to those of Doxil®. Plasma concentrations of doxorubicin from cancer patients were measured to determine the pharmacokinetics profile. The geometric mean ratios (90% confidence intervals) of PEGADRIA /Doxil® for free doxorubicin and encapsulated doxorubicin were similar. Conclusion: PEGADRIA was found to have similar physicochemical profile compared to Doxil®. In addition, it was safe and bioequivalent to Doxil® in ovarian cancer patients.

A New Topical Formulation of Minoxidil and Finasteride Improves Hair Growthin Men with Androgenetic Alopecia

Objectives: To compare the safety and efficacy of MorrF (combination of Minoxidil [5%]+Finasteride [0.1%] lipid solution) with Minoxidil (5%) solution in adult male patients suffering from Androgenetic Alopecia (AGA). Background: AGA is one of the three most common forms of non-scarring alopecia with approximately 95% of hair loss cases in men and women. Fifty percent of men by age 50 years exhibit some degree of AGA. Currently there are two effective treatments available for the treatment of AGA in men: topical Minoxidil and oral Finasteride. Clinical studies have demonstrated that both Minoxidil and Finasteride have well established therapeutic effect in the management of AGA. Materials and methods: Safety study in rats was carried out for 28 days with topical application of MorrF twice a day for 28 days. Human Pharmacokinetics (PK) and efficacy study was conducted in male patients suffering from Androgenetic Alopecia. PK parameters were determined after 2 weeks of MorrF administration. For efficacy study patients were randomized to receive either MorrF or Minoxidil (5%) alone for 24 weeks. Patients administered 1 mL of the either solution twice day on the effected part of the scalp. Results: Topical treatment of MorrF was found to be well-tolerated in rats and humans. Pharmacokinetics study in human showed the steady state Cmax,ss and exposure (AUC0-τ,ss) for Minoxidil to be 2.7 ng/mL and 19.3 ng.h/mL respectively whereas the steady state maximum Finasteride concentration (Cmax,ss) was 0.6 ng/mL and exposure (AUC0-τ,ss) of Finasteride was found to be 6.3 ng.h/mL. Significantly more patients treated with MorrF showed greater improvement in Investigator score (65% vs. 26%), global photographic assessment (89% vs. 60%) and patient’s self-assessed questionnaire as compared to Minoxidil alone. Conclusion: Topical formulation of MorrF was shown to have clinically significant improvement in terms of hair growth as compared to Minoxidil (5%) alone.