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- Intranasal delivery of nanostructured lipid carriers, solid lipid nanoparticles and nanoemulsions: a current overview of in vivo studiesPublication . Costa, Cláudia Pina; Moreira, João Nuno; Lobo, José Manuel Sousa; Silva, Ana CatarinaThe management of the central nervous system (CNS) disorders is challenging, due to the need of drugs to cross the blood‒brain barrier (BBB) and reach the brain. Among the various strategies that have been studied to circumvent this challenge, the use of the intranasal route to transport drugs from the nose directly to the brain has been showing promising results. In addition, the encapsulation of the drugs in lipid-based nanocarriers, such as solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs) or nanoemulsions (NEs), can improve nose-to-brain transport by increasing the bioavailability and site-specific delivery. This review provides the state-of-the-art of in vivo studies with lipid-based nanocarriers (SLNs, NLCs and NEs) for nose-to-brain delivery. Based on the literature available from the past two years, we present an insight into the different mechanisms that drugs can follow to reach the brain after intranasal administration. The results of pharmacokinetic and pharmacodynamics studies are reported and a critical analysis of the differences between the anatomy of the nasal cavity of the different animal species used in in vivo studies is carried out. Although the exact mechanism of drug transport from the nose to the brain is not fully understood and its effectiveness in humans is unclear, it appears that the intranasal route together with the use of NLCs, SLNs or NEs is advantageous for targeting drugs to the brain. These systems have been shown to be more effective for nose-to-brain delivery than other routes or formulations with non-encapsulated drugs, so they are expected to be approved by regulatory authorities in the coming years.
- Thermosensitive nasal in situ gels of lipid-based nanosystems to improve the treatment of Alzheimer’s DiseasePublication . Cunha, Sara; Forbes, Ben; Lobo, José Manuel Sousa; Silva, Ana CatarinaThermosensitive in situ gels are promising formulations for the management of Alzheimer’s disease (AD), since they increase the residence time of lipid-based nanosystems in the nasal cavity, improving drug therapeutic efficacy. The purpose of this study is to prepare thermosensitive in situ gels with anticholinesterase inhibitor (RVG)-loaded nanostructured lipid carriers (NLC) and nanoemulsions to improve the residence time of the formulations in the nasal cavity. Different concentrations of thermosensitive polymers were added to the RVG-loaded NLC and to the RVG-loaded nanoemulsion to optimize the gelation temperature of the in situ gels; concentrations of 17% (%, w/w) of Kolliphor® P407 and 0.3% (%, w/w) of MethocelTM K4M were selected. The in situ gels of the RVG-loaded NLC and RVG-loaded nanoemulsion had a particle size, PDI, ZP, and pH of, respectively: 141.70 ± 0.40 nm and 146.10 ± 1.73 nm; 0.45 ± 0.00 and 0.43 ± 0.02; −4.06 ± 1.03 mV and −4.09 ± 0.71 mV, 6.60 ± 0.01 and 7.00 ± 0.02. In addition, these in situ gels showed a non-Newtonian plastic behavior, and the texture parameters presented desirable values for nasal administration. From these results, we concluded that the developed in situ gels can be used to improve the treatment of AD through the nose-to-brain route.
- Hematopoietic growth factorsPublication . Silva, Ana Catarina; Moreira, João Nuno; Lobo, José Manuel Sousa
- Current applications of pharmaceutical biotechnologyPublication . Silva, Ana Catarina; Moreira, João Nuno; Lobo, José Manuel Sousa; Almeida, HugoThis book offers an authoritative review of biopharmaceuticals and their clinical relevance. Biopharmaceuticals have been showing high therapeutic potential by means of biological and biosimilar medicines, particularly for the treatment of cancer, chronic diseases (e.g. diabetes, Crohn's disease, psoriasis and rheumatoid arthritis), neurodegenerative disorders (e.g. multiple sclerosis), and they have also been contributing to the progress of innovative therapies such as assisted reproductive medicine. Since the eighties, several biopharmaceuticals have been approved and, due to patents expiration, many biosimilars are also marketed. In this book, readers will find the most relevant updated information about the main clinical applications of pharmaceutical biotechnology. The authors provide expert analysis about the industrial challenges of recombinant proteins and the different classes of biopharmaceuticals, including monoclonal antibodies, vaccines, growth factors and stem cells. Topics such as bioprinting technologies in tissue engineering, gene therapy and personalized medicine are also covered in this book. Professionals, students and researchers interested in this field will find this work an important account.
- Editorial: applications of Solid Lipid Nanoparticles (SLN) and Nanostructured Lipid Carriers (NLC): state of the artPublication . Silva, Ana Catarina; Amaral, Maria Helena; Lobo, José Manuel Sousa; Almeida, Hugo
- Preparações vaginais: ontem, hoje e amanhãPublication . Silva, Ana Catarina; Lobo, José Manuel Sousa; Correia, Armanda do CarmoAs preparações farmacêuticas para aplicação vaginal são usadas desde a Antiguidade para tratar afeções vaginais. A atuação local de fármacos administrados na vagina promove a eficácia dos tratamentos e diminui possíveis efeitos tóxicos. Além disso, algumas moléculas pequenas e lipófilas conseguem permear a parede vaginal, sendo absorvidas para a corrente circulatória. A possibilidade de absorção sistémica através da vagina destaca-a como uma alternativa à via oral, com vantagens como o facto de evitar a primeira passagem hepática e os efeitos adversos gastrintestinais que se verificam com alguns fármacos. As formas farmacêuticas de libertação modificada permitem melhorar alguns aspetos da farmacocinética dos fármacos e tornam as administrações menos frequentes, o que promove a adesão à terapêutica e, consequentemente, a eficácia. As estratégias de libertação modificada para a via vaginal incluem sistemas de libertação, como anéis ou películas vaginais, sistemas mucoadesivos e nanossistemas. Novas possibilidades terapêuticas adequadas a esta via têm surgido, das quais se destacam a administração de microbicidas para prevenção da transmissão do virus da imunodeficiência humana e a administração de biofármacos, incluindo vacinas e anticorpos monoclonais com propriedades espermicidas, antivíricas e antifúngicas.
- Design, characterization, and clinical evaluation of argan oil nanostructured lipid carriers to improve skin hydrationPublication . Tichota, Deise Michele; Silva, Ana Catarina; Lobo, José Manuel Sousa; Amaral, Maria HelenaGiven its advantages in skin application (eg, hydration, antiaging, and protection), argan oil could be used in both dermatological and cosmetic formulations. Therefore, the preparation of nanostructured lipid carriers (NLCs) using argan oil as a liquid lipid is a promising technique, since the former constitute well-established systems for dermal delivery. The aim of this work was to develop a topical formulation of argan oil NLCs to improve skin hydration. Firstly an NLC dispersion was developed and characterized, and afterward an NLC-based hydrogel was prepared. The in vivo evaluation of the suitability of the prepared formulation for the proposed application was assessed in volunteers, by measuring different skin-surface parameters for 1 month. An argan oil NLC-based hydrogel formulation was successfully prepared and characterized. Moreover, the entrapment of the NLCs in the hydrogel net did not affect their colloidal sizes. Additionally, it was observed that this formulation precipitated an increase in skin hydration of healthy volunteers. Therefore, we concluded that the preparation of NLC systems using argan oil as the liquid lipid is a promising strategy, since a synergistic effect on the skin hydration was obtained (ie, NLC occlusion plus argan oil hydration).
- Applications of polymeric and lipid nanoparticles in ophthalmic pharmaceutical formulations: present and future considerationsPublication . Almeida, Hugo; Amaral, Maria Helena; Lobão, Paulo; Silva, Ana Catarina; Lobo, José Manuel SousaThe unique properties and characteristics of ocular tissues and the whole set of defence mechanisms of the ocular globe make the instillation of ocular drugs into a difficult task with a low rate of therapeutic response. One of the challenges for the new generation of ophthalmic pharmaceutical formulations is to increase the bioavailability of drugs administered by the ocular route and, therefore, their therapeutic efficacy. This can be achieved with the use of some strategies that provide an increase in the formulation pre-corneal residence time, mucoadhesion and penetration across the eye tissues. Colloidal carrier systems have been very successfully used for the selective and targeted delivery of drugs for several routes of administration. In this context, nanoparticles prepared with specific polymers or lipids and coated, dispersed or suspended in polymer solutions with mucoadhesion properties or in situ gelling properties will be an excellent strategy that deserves attention and further research. In this review, the characteristics and main properties of polymeric and lipid nanoparticles are discussed and examples and advantages of the application of these colloidal carrier systems for the ophthalmic administration of drugs are presented. The future directions of the research required in this specific field are also presented.
- Hormones, blood products, and therapeutic enzymesPublication . Silva, Ana Catarina; Costa, Cláudia Pina; Almeida, Hugo; Moreira, João Nuno; Lobo, José Manuel SousaTherapeutic uses of biological medicines are diverse and include active substances from different classes. This chapter provides an overview on the clinical applications of biological medicines containing hormones, blood products, and therapeutic enzymes. Currently, therapeutic hormones have 78 approved medicines, including insulin and analogs, glucagon and analogs, growth hormone, gonadotropins (follicle-stimulating hormone, luteinizing hormone, and human chorionic gonadotropin), thyroid-stimulating hormone, and parathyroid hormone. In contrast, recombinant blood products, and particularly blood factors, anticoagulants, and thrombolytic agents, incorporate 49 approved biological medicines. Regarding recombinant therapeutic enzymes, there are 22 approved medicines. Among the referred biological medicines, there are six biosimilar hormones, and no biosimilars have been approved for recombinant blood products and therapeutic enzymes, which is unexpected.Current investigations on recombinant hormones, recombinant blood products, and therapeutic enzymes seem to follow the same directions, searching for alternative non-injectable administration routes, development of new recombinant molecules with improved pharmacokinetic properties and discovering new clinical applications for approved medicines. These approaches are showing positive results and new medicines are expected to reach clinical approval in the coming years. Future prospects also include the approval of more biosimilar medicines.
- Using the quality by design (QbD) approach to optimize formulations of lipid nanoparticles and nanoemulsions: a reviewPublication . Cunha, Sara; Costa, Cláudia Pina; Moreira, João Nuno; Lobo, José Manuel Sousa; Silva, Ana CatarinaQuality-by-design (QbD) approach has been applied to optimize lipid-based nanosystems formulations, including solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC) and nanoemulsions, besides being increasingly requested by regulatory authorities. Different mathematical models and statistical tests have been used, with similar conclusions regarding the parameters that influence the physical features of the resulting nanosystems. These include, variations in composition (e.g. lipid(s) and/or emulsifier(s)) and manufacturing parameters (e.g. emulsification rate and/or time, sonication amplitude and/or time, and homogenization pressure and/or cycles). These are critical parameters that influence nanoparticle/globule mean size, polydispersity index, zeta potential, drug encapsulation efficiency and in vitro drug release. This review addresses the concepts and applications of QbD for the development of lipid-based nanosystems, reporting successful examples published in the last 2 years. Although, some limitations have been identified, it is expected that in the upcoming years the application of QbD in pharmaceutical development will be an established approach.