Poloxamer 407, also known by the trademark Pluronic
F127, is a water-soluble, non-ionic triblock copolymer that is made up of a hydrophobic residue of polyoxypropylene (POP) between the two ...hydrophilic units of polyoxyethylene (POE). Poloxamer 407-based hydrogels exhibit an interesting reversible thermal characteristic. That is, they are liquid at room temperature, but they assume a gel form when administered at body temperature, which makes them attractive candidates as pharmaceutical drug carriers. These systems have been widely investigated in the development of mucoadhesive formulations because they do not irritate the mucosal membranes. Based on these mucoadhesive properties, a simple administration into a specific compartment should maintain the required drug concentration in situ for a prolonged period of time, decreasing the necessary dosages and side effects. Their main limitations are their modest mechanical strength and, notwithstanding their bioadhesive properties, their tendency to succumb to rapid elimination in physiological media. Various technological approaches have been investigated in the attempt to modulate these properties. This review focuses on the application of poloxamer 407-based hydrogels for mucosal drug delivery with particular attention being paid to the latest published works.
Advances in nanotechnology have favored the development of novel colloidal formulations able to modulate the pharmacological and biopharmaceutical properties of drugs. The peculiar physico-chemical ...and technological properties of nanomaterial-based therapeutics have allowed for several successful applications in the treatment of cancer. The size, shape, charge and patterning of nanoscale therapeutic molecules are parameters that need to be investigated and modulated in order to promote and optimize cell and tissue interaction. In this review, the use of polymeric nanoparticles as drug delivery systems of anticancer compounds, their physico-chemical properties and their ability to be efficiently localized in specific tumor tissues have been described. The nanoencapsulation of antitumor active compounds in polymeric systems is a promising approach to improve the efficacy of various tumor treatments.
The controlled release of a compound entrapped in a biocompatible formulation is a sought-after goal in modern pharmaceutical technology. Zein is a hydrophobic protein which has several advantageous ...properties that make it suitable for use as a biocompatible and degradable material under physiological conditions. It is, therefore, proposed for different biomedical and pharmaceutical applications. In particular, due to its gelling properties, it can be used to form a polymeric network able to preserve biomolecules from harsh environments. The current study was designed to investigate the influence of different probes on the rheological properties of gels made up of zein, in order to characterize the systems as a function of the polymer concentration. Four model compounds characterized by different physico-chemical properties were entrapped in zein gels, and different behaviors (viscoelastic or pronounced solid-like characteristics) of the systems were observed. Zein-based gels showed various release profiles of the encapsulated compounds, suggesting that there are different interaction rates between the probes and the polymeric matrix.
Sclareol (labd‑14‑ene‑8,13‑diol), a phytochemical compound belonging to labdane-type diterpenes, has recently attracted noteworthy attention because of its peculiar pharmacological properties. The ...foremost obstacle to an efficacious application and use of this molecule is its unfavorable bioavailability due to its poor aqueous solubility. In this investigation sclareol was encapsulated within PLGA nanoparticles with the aim of favoring its administration in physiological media, increasing its anticancer activity and obtaining a stable colloidal formulation. These nanoparticles containing sclareol were characterized by a mean diameter of 100–150 nm, a narrow size distribution and a negative surface charge. The active compound was efficiently retained by the polymeric structure and did not induce any physical destabilization. The coating of the PLGA nanoparticles with hyaluronic acid (1.5 MDa) increased the antitumor efficacy of the encapsulated drug against human breast cancer cells expressing the hyaluronan receptors (MCF-7 and MDA-MB468) while a similar pharmacological effect was obtained on human colon carcinoma cells (CaCo-2). CLSM analysis demonstrated the intracellular localization of fluorescent nanosystems after 3 h incubation.
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•Sclareol (SCL) has been encapsulated within PLGA nanoparticles•The nanoencapsulation of SCL favors its administration in physiological media•The coating of SCL-nanoparticles with hyaluronan increases their anticancer activity on HA+ cells
The encapsulation of miR-34a into chitosan/PLGA nanoparticles in order to obtain nanoplexes useful for the modulation of the biopharmaceutical features of the active compound was studied. The ...nanoplexes were obtained through nanoprecipitation and were characterized by a mean diameter of ~160 nm, a good size distribution and a positive surface charge. The structure of the nanoparticles allowed a high level of entrapment efficiency of the miR-34a and provided protection of the genetic material from the effects of RNase. A high degree of transfection efficiency of the nanoplexes and a significant in vitro antitumor effect against multiple myeloma cells was demonstrated. The therapeutic properties of the nanoplexes were evaluated in vivo against human multiple myeloma xenografts in NOD-SCID mice. The systemic injection of miR-34a mimic-loaded nanoparticles significantly inhibited tumor growth and translated into improved survival of the laboratory mice. RT-PCR analysis carried out on retrieved tumors demonstrated the presence of a high concentration of miR-34a mimics. The integrity of the nanoplexes remained intact and no organ toxicity was observed in treated animals.
Bone defects pose a heavy burden on patients, orthopedic surgeons, and public health resources. Various pathological conditions cause bone defects including trauma, tumors, inflammation, ...osteoporosis, and so forth. Auto‐ and allograft transplantation have been developed as the most commonly used clinic treatment methods, among which autologous bone grafts are the golden standard. Yet the repair of bone defects, especially large‐volume defects in the geriatric population or those complicated with systemic disease, is still a challenge for regenerative medicine from the clinical perspective. The fast development of biomaterials and nanomedicine favors the emergence and promotion of efficient bone regeneration therapies. In this review, we briefly summarize the progress of novel biomaterial and nanomedical approaches to bone regeneration and then discuss the current challenges that still hinder their clinical applications in treating bone defects.
We present an overview of common causes of bone defects, the unmet clinical needs, and the utility of biomaterials and nanotechnology to facilitate bone regeneration. Besides, we propose several key approaches to improve bone repair strategies. This perspective provides a guidance for future research direction of bone repair to improve treatment efficiency in both clinical and research perspectives.
The high frequency of
-promoting mutations and the increased expression of
mRNA in anaplastic thyroid cancer (ATC) make TERT a suitable molecular target for the treatment of this lethal neoplasm. In ...this study, we encapsulated an anti-
oligonucleotide in biocompatible nanoparticles and analyzed the effects of this novel pharmaceutical preparation in preclinical models of ATC. Biocompatible nanoparticles were obtained in an acidified aqueous solution containing chitosan, anti-
oligoRNAs, and poloxamer 188 as a stabilizer. The effects of these anti-
nanoparticles (Na-siTERT) were tested
on ATC cell lines (CAL-62 and 8505C) and
on xenograft tumors obtained by flank injection of CAL-62 cells into SCID mice. The Na-siTERT reduced the viability and migration of CAL-62 and 8505C cells after 48-hour incubation. Intravenous administration (every 48 hours for 13 days) of this encapsulated drug in mice hosting a xenograft thyroid cancer determined a great reduction in the growth of the neoplasm (about 50% vs. untreated animals or mice receiving empty nanoparticles), and decreased levels of Ki67 associated with lower hTERT expression. Moreover, the treatment resulted in minimal invasion of nearby tissues and reduced the vascularity of the xenograft tumor. No signs of toxicity appeared following this treatment. Telomere length was not modified by the Na-siTERT, indicating that the inhibitory effects of neoplasm growth were independent from the enzymatic telomerase function. These findings demonstrate the potential suitability of this anti-TERT nanoparticle formulation as a novel tool for ATC treatment.
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In recent decades, nanotechnology has made phenomenal strides in the pharmaceutical field, favouring the improvement of the biopharmaceutical properties of many active compounds. Many liposome-based ...formulations containing antitumor, antioxidant and antifungal compounds are presently on the market and are used daily (for example Doxil
/Caelyx
and Ambisome
). Polymeric nanoparticles have also been used to entrap many active compounds with the aim of improving their pharmacological activity, bioavailability and plasmatic half-life while decreasing their side effects. The modulation of the structural/morphological properties of nanoparticles allows us to influence various technological parameters, such as the loading capacity and/or the release profile of the encapsulated drug(s). Amongst the biocompatible polymers, poly(D,L-lactide) (PLA), poly(D,L-glycolide) (PLG) and their co-polymers poly(lactide-co-glycolide) (PLGA) are the most frequently employed due to their approval by the FDA for human use. The aim of this review is to provide a description of the foremost recent investigations based on the encapsulation of amphotericin B in PLGA nanoparticles, in order to furnish an overview of the technological properties of novel colloidal formulations useful in the treatment of Leishmaniasis. The pharmacological efficacy of the drug after nanoencapsulation will be compared to the commercial formulations of the drug (i.e., Fungizone
, Ambisome
, Amphocil
and Abelcet
).
The introduction of nanotechnology into pharmaceutical application revolutionized the administration of antitumor drugs through the modulation of their accumulation in specific organs/body ...compartments, a decrease in their side-effects and their controlled release from innovative systems. The use of plant-derived proteins as innovative, safe and renewable raw materials to be used for the development of polymeric nanoparticles unlocked a new scenario in the drug delivery field. In particular, the reduced size of the colloidal systems combined with the peculiar properties of non-immunogenic polymers favored the characterization and evaluation of the pharmacological activity of the novel nanoformulations. The aim of this review is to describe the physico-chemical properties of nanoparticles composed of vegetal proteins used to retain and deliver anticancer drugs, together with the most important preparation methods and the pharmacological features of these potential nanomedicines.
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