Pharmaceutical Strategies Research Articles

Novel Pharmaceutical Strategy for Selective Abrogation of Thrombospondin 1‐Induced Vascular Dysfunctions via Decoy recombinant CD47

Substantial elevation in thrombospondin 1 (TSP1)‐plasma levels have been consistently implicated in in pathogenesis of a variety of fatal cardiovascular conditions, such as ischemia‐reperfusion injury, pulmonary hypertension and coronary artery disease.While domain mapping on monomeric TSP1 reveals a broad interaction network, up to 83 ligands and receptors, TSP1‐initiated signal cascades through its cognate receptor CD47 (a ubiquitous plasma membrane protein) have been directly correlated with cardiovascular dysfunction. There is only one systemic monoclonal antibody ‐ currently in clinical phase I ‐ to interfere with TSP1 and its network, and it is indicated for cancer therapy.Our work provides “proof‐of‐concept” of a novel anti‐TSP1 pharmacological strategy, relying on extraneous administration of recombinant human CD47‐derived peptide (rh‐CD47p), which serves two distinct, yet equally important goals: First, exogenous rh‐CD47p functions as a circulating decoy receptor protein to specifically bind TSP1 molecules, which are abnormally elevated in plasma. Consequently, rh‐CD47p‐bound TSP1 cannot bind its endogenous receptor CD47 expressed on vascular endothelium, leading to mitigation of all intracellular down‐stream molecules, and improvement of TSP1‐inhibited vasodilation. The second aim can be better achieved via adopting a pharmaceutical liposomal system. Multiple rh‐CD47p coupled onto each nano‐liposome can bind several circulating TSP1 molecles, leading to formation of many complexes between liposomal‐rh‐CD47p and TSP1, which can then be rapidly eliminated via the reticulo‐endothelial system. In principle, the recombinant decoy protein rh‐CD47p is “nano‐modified” into a therapeutic platform to eliminate pathological excess of TSP1 from circulation.Our pilot studies were carried out in an ex vivo model using isolated mouse thoracic aortic segments. Initially, a pre‐treatment protocol for rh‐CD47p (added 15 min prior to TSP1 incubation) was shown to significantly ameliorate the TSP1‐impairement of endothelium‐dependent vasodilation (p<0.0001, rh‐CD47p+TSP1 vs. TSP1; p>0.05 rh‐CD47p+TSP1 vs. control, n=6). To mimic pre‐existing high circulating levels of TSP1 in patients, a reverse order of incubation was investigated. In this post‐treatment set‐up, where TSP1 incubation was started 15 min prior to rh‐CD47p addition, a marked reversal of TSP1‐impaired vasodilation was observed, back to the same level as controls (p<0.0001 rh‐CD47p+TSP1 vs. TSP1; p>0.05 rh‐CD47p+TSP1 vs. control, n=4). Simultaneously, titration of the binding molar ratios of rh‐CD47p:TSP1 was examined, in order to find the optimal dose of rh‐CD47p for maximum recovery from TSP1‐induced vascular impairment. Stoichiometric binding of rh‐CD47p and TSP1, at different incremental ratios, was further confirmed via western blotting, and immune‐precipitation, both in cell‐free setting.Our current results indicate the feasibility of exogenous administration of rh‐CD47p as a unique pharmacological strategy to improve TSP1‐impaired endothelium‐dependent vasodilation, thus providing a solid foundation for our novel decoy CD47‐coated nano‐formulation for TSP1‐associated cardiovascular complications.Support or Funding InformationMidwestern University intramural funding

Estratégia de proteção de patentes farmacêuticas: o caso do atazanavir

O alto custo dos medicamentos antirretrovirais (ARVs) justifica estudos sobre estratégias de patenteamento farmacêutico vis-à-vis à política pública brasileira de acesso universal aos ARVs. A análise da evolução das tendências tecnológicas através do estudo de patentes fornece também uma visão dos envolvidos no desenvolvimento de uma tecnologia. Para traçar o perfil de patenteamento do antirretroviral atazanavir, no Brasil e no mundo, foi realizado um estudo na base de dados Thomson Reuters Integrity que identificou o desenvolvimento, produção e comercialização desse produto. Foram identificados 49 documentos de patentes, tendo a proteção dessa tecnologia se iniciado em 1996, com a empresa Novartis e seu licenciado, a Bristol, que reivindicaram proteção para a molécula. Prossegue até 2013, com proteção de invenções incrementais, originárias na China. O estudo possibilitou discutir a importância do sistema de patentes na promoção da inovação, e evidenciar tipos diversos de proteção para um produto e tecnologias relacionadas.

Effects of quercetin, a natural phenolic compound, in the differentiation of human mesenchymal stem cells (MSC) into adipocytes and osteoblasts

Natural phenols may have beneficial properties against oxidative stress, which is associated with aging and major chronic aging-related diseases, such as loss of bone mineral mass (osteoporosis) and diabetes. The main aim of this study was to analyze the effect of quercetin, a major nutraceutical compound present in the “Mediterranean diet”, on mesenchymal stem-cell (MSC) differentiation. Such cells were induced to differentiate into osteoblasts or adipocytes in the presence of two quercetin concentrations (0.1 and 10μM). Several physiological parameters and the expression of osteoblastogenesis and adipogenesis marker genes were monitored. Quercetin (10μM) inhibited cell proliferation, alkaline phosphatase (ALPL) activity and mineralization, down-regulating the expression of ALPL, collagen type I alpha 1 (COL1A1) and osteocalcin [bone gamma-carboxyglutamate protein (BGLAP)] osteoblastogenesis-related genes in MSC differentiating into osteoblasts. Moreover, in these cultures, CCAAT/enhancer-binding protein alpha (CEBPA) and peroxisome proliferator-activated receptor gamma 2 (PPARG2) adipogenic genes were induced, and cells differentiated into adipocytes were observed. Quercetin did not affect proliferation, but increased adipogenesis, mainly at 10-μM concentration in MSC induced to differentiate to adipocytes. β- and γ-catenin (plakoglobin) nuclear levels were reduced and increased, respectively, in quercetin-treated cultures. This suggests that the effect of high concentration of quercetin on MSC osteoblastic and adipogenic differentiation is mediated via Wnt/β-catenin inhibition. In conclusion, quercetin supplementation inhibited osteoblastic differentiation and promoted adipogenesis at the highest tested concentration. Such possible adverse effects of high quercetin concentrations should be taken into account in nutraceutical or pharmaceutical strategies using such flavonol.

MP24-04 THE UROPATHOGENIC ESCHERICHIA COLI PILUS USHER CONTROLS PROTEIN INTERACTIONS VIA DOMAIN MASKING AND IS FUNCTIONAL AS AN OLIGOMER

You have accessJournal of UrologyInfections/Inflammation/Cystic Disease of the Genitourinary Tract: Kidney & Bladder I1 Apr 2016MP24-04 THE UROPATHOGENIC ESCHERICHIA COLI PILUS USHER CONTROLS PROTEIN INTERACTIONS VIA DOMAIN MASKING AND IS FUNCTIONAL AS AN OLIGOMER Glenn Werneburg, Hemil Chauhan, Nadine Henderson, and David Thanassi Glenn WerneburgGlenn Werneburg More articles by this author , Hemil ChauhanHemil Chauhan More articles by this author , Nadine HendersonNadine Henderson More articles by this author , and David ThanassiDavid Thanassi More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.760AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Urinary tract infections (UTIs), the majority of which are caused by E. coli, are among the most common and costly human infections. Uropathogenic E. coli strains use the chaperone/usher (CU) pathway to construct surface structures termed pili, adhesive organelles that facilitate binding to bladder or kidney epithelial cells, thus promoting colonization and infection. The CU pilus biogenesis pathway requires a periplasmic chaperone protein and an outer membrane protein, the usher. We sought to gain a mechanistic understanding of how the usher protein catalyzes the assembly of pili and identify new opportunities for therapeutics designed to target specific steps of the process. METHODS We monitored pilus subunit interactions with various usher domains using fluorescence approaches and various biochemical and genetic techniques. RESULTS The usher (FimD), an oligomer, has 5 domains: a periplasmic N-terminal domain (N), a transmembrane channel domain gated by an internal plug domain, and two periplasmic C-terminal domains (C1, C2). We identified the C domains as the high affinity binding site of FimD, and confirmed that the N domain provides an additional, lower affinity, binding site. We show that the C domains are ″masked″ by the plug domain prior to FimD activation. Upon activation by pilus subunit binding to the usher′s N domain, the plug domain undergoes a drastic positional shift, freeing the high affinity C domains for subunit binding. We demonstrate that a lectin domain on a pilus subunit is necessary and sufficient for plug expulsion. Our data indicate that the pilus subunit is then handed off from the N to the (now free) C domains in a process driven by differential affinity. Concurrent with this handoff, the growing pilus fiber is then secreted to an extracellular position where it can adhere to the urinary tract and facilitate UTI. Further, in vivo we show that FimD is functional in trans, suggesting a basis for function of the usher oligomer. CONCLUSIONS Our study identified novel and discrete aspects of pilus assembly, each of which could potentially be targeted by a novel pharmaceutical strategy. A small molecule inhibitor that effectively prevents usher activation, N-to-C handoff, or affinity differential, could serve as an anti-infective drug. This therapeutic would prevent infection by disrupting cell adhesion, but without killing bacteria, and thus would not select for antibiotic-resistant strains. Our fluorescence assays are poised for adaptation as tools for screening large libraries of molecules to identify such a drug. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e271 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Glenn Werneburg More articles by this author Hemil Chauhan More articles by this author Nadine Henderson More articles by this author David Thanassi More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Treatment with TUG891, a free fatty acid receptor 4 agonist, restores adipose tissue metabolic dysfunction following chronic sleep fragmentation in mice.

Sleep fragmentation (SF), a frequent occurrence in multiple sleep and other diseases leads to increased food intake and insulin resistance via increased macrophage activation and inflammation in visceral white adipose tissue (VWAT). Free fatty acid receptor 4 (FFA4) is reduced in pediatric sleep apnea patients and FFA4 agonists have been proposed in the treatment of obesity and metabolic dysfunction. Male mice were subjected to SF exposures for 6 weeks, and treated during the last 2 weeks with either TUG891, a potent and selective FFA4 agonist, or vehicle (Veh). Glucose and insulin tolerance tests and VWAT insulin sensitivity tests were conducted (phosphorylated Akt/total Akt), along with flow cytometric assessments of VWAT macrophage polarity, and T-cell lymphocyte subsets. SF-TUG891 mice showed reduction in food consumption, weight gain and VWAT mass. Furthermore, TUG891 treatment ameliorated glucose tolerance test and insulin tolerance test responses and increased VWAT p-Akt/Akt responses to insulin. Increases in M1/M2 macrophages and decreased Treg counts in VWAT associated with SF were markedly improved by TUG891, and VWAT macrophages from TUG891-treated mice had markedly attenuated insulin resistance effects on naïve cultured adipocytes. Treatment with an FFA4 agonist reverses SF-induced food intake increases and gains in body weight, and significantly attenuates VWAT inflammation and insulin resistance. Thus, interventional dietary or pharmaceutical strategies aimed at increasing FFA4 activity may serve as potentially useful adjunctive therapies for sleep disorders accompanied by metabolic morbidity.

The race for Ebola drugs: pharmaceuticals, security and global health governance

The international Ebola response mirrors two broader trends in global health governance: (1) the framing of infectious disease outbreaks as a security threat; and (2) a tendency to respond by providing medicines and vaccines. This article identifies three mechanisms that interlink these trends. First, securitisation encourages technological policy responses. Second, it creates an exceptional political space in which pharmaceutical development can be freed from constraints. Third, it creates an institutional architecture that facilitates pharmaceutical policy responses. The ways in which the securitisation of health reinforces pharmaceutical policy strategies must, the article concludes, be included in ongoing efforts to evaluate them normatively and politically.

Liposheres as a Novel Carrier for Lipid Based Drug Delivery: Current and Future Directions.

Researchers are facing challenges to develop robust formulation and to enhance the bioavailability of poorly water-soluble drugs towards clinical applications. The development of new drug molecule alone is not adequate to assure ample pharmacotherapy of various diseases. Considerable results obtained from in vitro studies are not supported by in vivo data due to inadequate plasma drug concentrations. This may occur due to limited drug solubility and absorption. To resolve these problems, development of new drug delivery systems will be a promising approach. One of the promising pharmaceutical strategies is the use of lipospheres drug delivery system to deliver the poorly water-soluble drugs. Therefore, the present review described the methodology for manufacturing of lipospheres and factors influencing the formulation to deliver the drugs to the targeted site. Apart from that, this review also enlisted briefly the various applications of liposphers in medical and biomedical fields and critically discussed the recent patent system.

Development of a Drug Discovery Method Targeted to Stromal Tissue

Several diseases are characterized by alterations in the molecular distribution of vascular structures, presenting the opportunity to use monoclonal antibodies for clinical therapies. This pharmaceutical strategy, often referred to as "vascular targeting", has promise in promoting the discovery and development of selective biological drugs to regulate angiogenesis-related diseases such as cancer. Various experimental approaches have been utilized to discover accessible vascular markers of health and disease at the protein level. Our group has developed a new chemical proteomics technology to identify and quantify accessible vascular proteins in normal organs and at disease sites. Our developed methodology relies on the perfusion of animal models with suitable ester derivatives of biotin, which react with the primary amine groups of proteins as soon as the molecules are attached. This presentation reports biomedical applications based on vascular targeting strategies, as well as methodologies that have been used to discover new vascular targets. The identification of antigens located in the stromal tissue of pathological blood vessels may provide attractive targets for the development of antibody drugs. This method will also provide an efficient discovery target that could lead to the development of novel antibody drugs.

Long-term serial xenotransplantation of juvenile myelomonocytic leukemia recapitulates human disease in Rag2-/- c-/- mice

Juvenile myelomonocytic leukemia is a clonal malignant disease affecting young children. Current cure rates, even with allogeneic hematopoietic stem cell transplantation, are no better than 50%-60%. Pre-clinical research on juvenile myelomonocytic leukemia is urgently needed for the identification of novel therapies but is hampered by the unavailability of culture systems. Here we report a xenotransplantation model that allows long-term in vivo propagation of primary juvenile myelomonocytic leukemia cells. Persistent engraftment of leukemic cells was achieved by intrahepatic injection of 1×10(6) cells into newborn Rag2(-/-)γc(-/-) mice or intravenous injection of 5×10(6) cells into 5-week old mice. Key characteristics of juvenile myelomonocytic leukemia were reproduced, including cachexia and clonal expansion of myelomonocytic progenitor cells that infiltrated bone marrow, spleen, liver and, notably, lung. Xenografted leukemia cells led to reduced survival of recipient mice. The stem cell character of juvenile myelomonocytic leukemia was confirmed by successful serial transplantation that resulted in leukemia cell propagation for more than one year. Independence of exogenous cytokines, low donor cell number and slowly progressing leukemia are advantages of the model, which will serve as an important tool to research the pathophysiology of juvenile myelomonocytic leukemia and test novel pharmaceutical strategies such as DNA methyltransferase inhibition.

RHAMM splice variants confer radiosensitivity in human breast cancer cell lines.

Biomarkers for prognosis in radiotherapy-treated breast cancer patients are urgently needed and important to stratify patients for adjuvant therapies. Recently, a role of the receptor of hyaluronan-mediated motility (RHAMM) has been suggested for tumor progression. Our aim was (i) to investigate the prognostic value of RHAMM in breast cancer and (ii) to unravel its potential function in the radiosusceptibility of breast cancer cells. We demonstrate that RHAMM mRNA expression in breast cancer biopsies is inversely correlated with tumor grade and overall survival. Radiosusceptibility in vitro was evaluated by sub-G1 analysis (apoptosis) and determination of the proliferation rate. The potential role of RHAMM was addressed by short interfering RNAs against RHAMM and its splice variants. High expression of RHAMMv1/v2 in p53 wild type cells (MCF-7) induced cellular apoptosis in response to ionizing radiation. In comparison, in p53 mutated cells (MDA-MB-231) RHAMMv1/v2 was expressed sparsely resulting in resistance towards irradiation induced apoptosis. Proliferation capacity was not altered by ionizing radiation in both cell lines. Importantly, pharmacological inhibition of the major ligand of RHAMM, hyaluronan, sensitized both cell lines towards radiation induced cell death. Based on the present data, we conclude that the detection of RHAMM splice variants in correlation with the p53 mutation status could help to predict the susceptibility of breast cancer cells to radiotherapy. Additionally, our studies raise the possibility that the response to radiotherapy in selected cohorts may be improved by pharmaceutical strategies against RHAMM and its ligand hyaluronan.

Photochemical Mechanism of Riboflavin-Induced Degradation of Famotidine and a Suggested Pharmaceutical Strategy for Improving Photostability

The present study aimed to clarify the mechanism of photodegradation of famotidine with riboflavin (FMT/RF), and to develop a photochemically stabilized formulation of FMT/RF. Photochemical properties of RF were characterized by UV-VIS spectral analysis, reactive oxygen species (ROS) assay, and photostability testing. Pharmacokinetic study was conducted in rats after intravenous administration of FMT (1 mg/kg) formulation containing RF (0.01 mg/kg). The UV-VIS spectral pattern of RF partly overlapped with the sunlight spectrum, and ROS generation from photoirradiated RF was remarkable; thus, RF had high photoreactive potential. In the photostability testing, after irradiation (250 W/m2), degradation rate for FMT in FMT/RF was ca. 11-fold higher than that in FMT alone. The addition of radical scavengers to FMT/RF led to attenuated photodegradation of FMT/RF; in particular, the addition of L-ascorbic acid (vitamin C; VC) to FMT/RF showed ca. 86% inhibition of the photodegradation of FMT/RF. The pharmacokinetic study on FMT indicated that the addition of VC (1 mg/kg) to FMT/RF had no significant impact on the pharmacokinetic behavior of FMT. These findings suggest that ROS-mediated photochemical reaction would be involved in the photodegradation pathway of FMT/RF, and the complementary use of VC might be an attractive approach to improve the photostability of FMT/RF.

Pharma Pricing & Market Access Europe 2016--Health Network Communications' Tenth Annual Conference (February 23-25, 2016--London, UK).

Tighter national budgets and escalating drug prices continue to present challenges for pharmaceutical market access strategies and societal cost of care. As pharmaceutical companies and medical governmental advisory organizations enter tougher negotiations, hospital trusts and other dispensary firms face barriers to receiving the best medical treatment, and as a result patient access is limited. The 2016 HealthNetwork Communications' Pharma Pricing & Market Access Europe meeting brought together pharmaceutical, medical governmental advisory and stakeholders and market access/pricing consultants, to encourage discussions and negotiations into how to improve the drug pricing system and consequential market access strategies while achieving the respective reimbursement and affordability objectives.

Redeveloping Drugs Based on Existing Patents

With the advent of the era of knowledge economy and China’s join into WTO, the Problem of intellectual property rights of drug has become increasingly important to Pharmaceutical industry and even to all society. The Patent Protection is the most important part of intellectual property right of drug, which does not only act as a safe guard and stimulator to drug development, but also is a Powerful tool for drug development Providing comprehensive technology and law information. The paper analyzed some Pharmaceutical companies' strategies to develop new drug with Patent. An investigation of the U.S. Federal Trade Commission shows that, the pharmaceutical industry is more dependent on patents than any other industries; the industry prevents free competition, compensate R&D investment, and learn about new technical breakthroughs through patents. Chinese researchers have no strong awareness of using patent literatures, often neglecting acquisition and analysis of patent information. Therefore, the author summarized and analyzed current methods of how foreign pharmaceutical companies use patent information for drug development, to provide Chinese pharmaceutical companies with references on fully using patent resources to develop drugs

Adapting Pharmaceutical Pricing and Reimbursement Strategies for Achieving Universal Health Coverage in Nepal: Lessons from Selected Low- And Lower-Middle-Income Countries

Universal health coverage is increasingly being embraced by low- and high-income countries alike, and pharmaceuticals are an integral part of it. With Nepal adopting national health insurance policy and willing to implement the same, guidance regarding pharmaceutical pricing, coverage and reimbursement becomes the order of the day. This study reviews pricing and reimbursement policies and techniques in low- and lower-middle-income countries which are implementing or intend to implement universal health coverage schemes, and provides recommendations on policies and techniques applicable and most pertinent to Nepal. For this, relevant literature on 11 countries was searched. The countries studied here are at different stages of universal health coverage, and they are aligning their pharmaceutical pricing and reimbursement policies and techniques with their universal health coverage policy. Considerable variation exists among these countries in regard to pricing, ranging from ceiling pricing (based on cost-plus, external referencing or market-based technique) to free pricing. All these countries have framed their essential medicines list; few or all of the medicines in the list are provided free of charge to targeted groups. Different universal health coverage schemes are at work in these countries, financing strategy for which span tax-based, premium-based and payroll deductions. Reimbursement decisions are intricately linked with pricing, with majority of the countries putting into effect a fixed reimbursable amount strategy for reimbursed products. In regard to Nepal, as it is beginning its universal health coverage journey, the ideal approach would be a ceiling price for essential medicines (applicable to both in-insurance and out-insurance) and reference or index pricing for reimbursed products.

Crystal Structure of Feline Infectious Peritonitis Virus Main Protease in Complex with Synergetic Dual Inhibitors.

Coronaviruses (CoVs) can cause highly prevalent diseases in humans and animals. Feline infectious peritonitis virus (FIPV) belongs to the genus Alphacoronavirus, resulting in a lethal systemic granulomatous disease called feline infectious peritonitis (FIP), which is one of the most important fatal infectious diseases of cats worldwide. No specific vaccines or drugs have been approved to treat FIP. CoV main proteases (M(pro)s) play a pivotal role in viral transcription and replication, making them an ideal target for drug development. Here, we report the crystal structure of FIPV M(pro) in complex with dual inhibitors, a zinc ion and a Michael acceptor. The complex structure elaborates a unique mechanism of two distinct inhibitors synergizing to inactivate the protease, providing a structural basis to design novel antivirals and suggesting the potential to take advantage of zinc as an adjunct therapy against CoV-associated diseases. Coronaviruses (CoVs) have the largest genome size among all RNA viruses. CoV infection causes various diseases in humans and animals, including severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). No approved specific drugs or vaccinations are available to treat their infections. Here, we report a novel dual inhibition mechanism targeting CoV main protease (M(pro)) from feline infectious peritonitis virus (FIPV), which leads to lethal systemic granulomatous disease in cats. M(pro), conserved across all CoV genomes, is essential for viral replication and transcription. We demonstrated that zinc ion and a Michael acceptor-based peptidomimetic inhibitor synergistically inactivate FIPV M(pro). We also solved the structure of FIPV M(pro) complexed with two inhibitors, delineating the structural view of a dual inhibition mechanism. Our study provides new insight into the pharmaceutical strategy against CoV M(pro) through using zinc as an adjuvant therapy to enhance the efficacy of an irreversible peptidomimetic inhibitor.

Pharmaceutical Management of Small Abdominal Aortic Aneurysms: A Systematic Review of the Clinical Evidence

Management of abdominal aortic aneurysms (AAAs) relies on surgical repair of larger AAAs. Consequently medical interventions inhibiting AAA progression could greatly reduce the need for surgical repair. A spectrum of pharmaceutical strategies has been reported, albeit conclusions often appear contradictory. Given the longstanding interest in pharmaceutical AAA stabilization, a systematic review of the available literature is relevant. The aim is to provide an up to date systematic review of the available data on pharmaceutical therapies for stabilizing or impeding AAA growth. A search using Pubmed, Embase, Web of science, Cochrane, CINAHL, Academic Search Premier, and Science Direct identified 27 eligible papers that studied the clinical effect of the pharmaceutical therapy on AAA diameter growth. This review shows that there is currently no pharmaceutical strategy that reduces AAA growth. Most studies are of poor methodological quality. Initial promising reports are often not confirmed in subsequent larger studies, raising the possibility of selective reporting. There is currently no pharmaceutical means that halts AAA growth.

Pharmaceutical Cost-Containment Strategies – Opinions of the Pharmaceutical Industry and Hta Bodies in Latin America

Pharmaceutical Cost-Containment Strategies – Opinions of the Pharmaceutical Industry and Hta Bodies in Latin America

Topical Skin Cancer Therapy Using Doxorubicin-Loaded Cationic Lipid Nanoparticles and lontophoresis.

The topical administration of chemotherapeutics is a promising approach for the treatment of skin cancer; however, different pharmaceutical strategies are required to allow large amounts of drug to penetrate tumors. This work examined the potential of the anodic iontophoresis of doxorubicin-loaded cationic solid lipid nanoparticles (DOX-SLN) to increase the distribution and tumor penetration of DOX. A double-labeled cationic DOX-SLN composed of the lipids stearic acid and monoolein and a new BODIPY dye was prepared and characterized. The skin distribution and penetration of DOX were evaluated in vitro using confocal microscopy and vertical diffusion cells, respectively. The antitumor potential was evaluated in vivo through the anodic iontophoresis of DOX-SLN in squamous cell carcinoma induced in nude BALB/c mice. The encapsulation of DOX drastically altered the DOX partition coefficient and increased the distribution of DOX in the lipid matrix of the stratum corneum (SC). The association with iontophoresis created high-concentration drug reservoir zones in the follicles of the skin. Although the iontophoresis of a DOX solution increased the penetration of DOX in the viable epidermis by approximately 4-fold, the iontophoresis of cationic DOX-SLN increased the DOX penetration by approximately 50-fold. In vivo, the DOX-SLN iontophoretic treatment was effective in inhibiting tumor cell survival and tumor growth and was accompanied by an increase in keratinization and consequent cell death. These results indicate a strong and synergic effect of iontophoresis with DOX-SLN and provide a potential strategy for the treatment of skin cancer.

Development and In Vitro Evaluation of Vitamin E-Enriched Nanoemulsion Vehicles Loaded with Genistein for Chemoprevention Against UVB-Induced Skin Damage

There is a great need for effective protection against cutaneous pathologies arising from chronic exposure to harmful solar UVB radiations. A promising pharmaceutical strategy to improve the efficacy of chemotherapeutic/preventative natural compounds (e.g., soy isoflavone Genistein, Gen) is to enhance their dermal delivery using nanoemulsion (NE) formulations. This report investigates the development of nanoemulsified tocotrienol(T3)-rich fraction of red palm oil (Tocomin®), to yield an optimal NE delivery system for dermal photoprotection (z-average size <150 nm, ζ-potential ≈ -30 mV, polydispersity index < 0.25). Physicochemical characterization and photostability studies indicate NE formulations utilizing surfactant mixture (Smix) of Solutol® HS-15 (SHS15) blended with vitamin E TPGS (TPGS) as cosurfactant was significantly superior to formulations that utilized Lutrol® F68 (LF68) as the cosurfactant. A ratio of 60:40 of SHS15-TPGS-NE was further identified as lead Tocomin® NE topical platform using in vitro pharmaceutical skin reactivity studies that assess cutaneous irritancy and cytotoxicity. Prototype Tocomin® NE loaded with the antiphotocarcinogenic molecule Gen (Gen-Tocomin® NE) showed slow-release profile in both liquid and cream forms. Gen-Tocomin® NE also showed excellent biocompatibility, and provided substantial UVB protection to cultured subcutaneous L929 fibroblasts, indicating the great potential of our Tocomin® NE warranting further prototype development as topical pharmaceutical platform for skin photoprotection applications.

Pharmacokinetic comparison of different flubendazole formulations in pigs: A further contribution to its development as a macrofilaricide molecule

Despite the well established ivermectin activity against microfilaria, the success of human filariasis control programmes requires the use of a macrofilaricide compound. Different in vivo trials suggest that flubendazole (FLBZ), an anthelmintic benzimidazole compound, is a highly efficacious and potent macrofilaricide. However, since serious injection site reactions were reported in humans after the subcutaneous FLBZ administration, the search for alternative pharmaceutical strategies to improve the systemic availability of FLBZ has acquired special relevance both in human and veterinary medicine. The goal of the current experimental work was to compare the pharmacokinetic plasma behavior of FLBZ, and its metabolites, formulated as either an aqueous hydroxypropyl- β -cyclodextrin-solution (HPBCD), an aqueous carboxymethyl cellulose-suspension (CMC) or a Tween 80-based formulation, in pigs. Animals were allocated into three groups and treated (2 mg/kg) with FLBZ formulated as either a HPBCD-solution (oral), CMC-suspension (oral) or Tween 80-based formulation (subcutaneous). Only trace amounts of FLBZ parent drug and its reduced metabolite were measured after administration of the different FLBZ formulations in pigs. The hydrolyzed FLBZ (H-FLBZ) metabolite was the main analyte recovered in the bloodstream in pigs treated with the three experimental FLBZ formulations. The oral administration of the HPBCD-solution accounted for significantly higher (P < 0.05) Cmax and AUC (23.1 ± 4.4 μg h/mL) values for the main metabolite (H-FLBZ), compared with those observed for the oral CMC-suspension (AUC = 3.5 ± 1.0 μg h/mL) and injectable Tween 80-based formulation (AUC: 7.5 ± 1.7 μg h/mL). The oral administration of the HPBCD-solution significantly improved the poor absorption pattern (indirectly assessed as the H-FLBZ plasma concentrations) observed after the oral administration of the FLBZ-CMC suspension or the subcutaneous injection of the Tween 80 FLBZ formulation to pigs. Overall, the work reported here indicates that FLBZ pharmacokinetic behavior can be markedly changed by the pharmaceutical formulation.