Oral delivery of curcumin bound to chitosan nanoparticles cured Plasmodium yoelii infected mice

Anti-malarials are anti-cancers and vice versa - one arrow two sparrows

Repurposing is the novel means of drug discovery in modern science due to its affordability, safety and availability. Here, we systematically discussed the efficacy and mode of action of multiple bioactive, synthetic compounds and their potential derivatives which are used to treat/prevent malaria and cancer. We have also discussed the detailed molecular pathway involved in anti-cancer potentiality of an anti-malarial drug and vice versa. Although the causative agents, pathophysiology and manifestation of both the diseases are different but special emphasis has been given on similar pathways governing disease manifestation and the drugs which act through deregulating those pathways. Finally, a future direction has been speculated to combat these two diseases by a single agent developed using nanotechnology. Extended combination and new formulation of existing drugs for one disease may lead to the discovery of drug for other diseases like an arrow for two sparrows.

Activity of several kinds of drugs against Neospora caninum

Neosporosis caused by Neospora caninum is a serious disease in cattle and dogs worldwide. It is the major cause of abortion and neonatal mortality in cattle. In this study, we evaluated the anti-N. caninum activity of Chinese medicine extracts (curcumin, artemether), herbicides (atrazine, glyphosate), anticoccidiosis drugs (toltrazuril and ponazuril), cyclophosphamide, diminazene aceturate and praziquantel in vitro using parasite growth, replication and host cell invasion assays in human foreskin fibroblast cultures. Curcumin, artemether, atrazine, toltrazuril and ponazuril exhibited inhibitory activity with 50% growth inhibitory concentration (IC50) of 1.1±0.4, 1.0±0.05, 11.2±2.7, 30.3±2.0 and 33.3±4.1μg/ml, respectively, in the growth inhibition assay. They were also active against protozoa replication, but only curcumin was effective against host cell invasion. Glyphosate, cyclophosphamide, diminazene aceturate and praziquantel were ineffective. In an in vivo infection model, curcumin showed no activity against N. caninum infection. We showed that curcumin, artemether, atrazine, toltrazuril, and ponazuril exhibited anti-N. caninum activity in vitro, providing important information for further studies on anti-N. caninum drugs.

Simultaneously targeting inflammatory response and parasite sequestration in brain to treat Experimental Cerebral Malaria

Malaria afflicts around 200 million people annually, with a mortality number close to 600,000. The mortality rate in Human Cerebral Malaria (HCM) is unacceptably high (15–20%), despite the availability of artemisinin-based therapy. An effective adjunct therapy is urgently needed. Experimental Cerebral Malaria (ECM) in mice manifests many of the neurological features of HCM. Migration of T cells and parasite-infected RBCs (pRBCs) into the brain are both necessary to precipitate the disease. We have been able to simultaneously target both these parameters of ECM. Curcumin alone was able to reverse all the parameters investigated in this study that govern inflammatory responses, CD8⁺ T cell and pRBC sequestration into the brain and blood brain barrier (BBB) breakdown. But the animals eventually died of anemia due to parasite build-up in blood. However, arteether-curcumin (AC) combination therapy even after the onset of symptoms provided complete cure. AC treatment is a promising therapeutic option for HCM.

Nanocarriers for the delivery of active ingredients and fractions extracted from natural products used in traditional Chinese medicine (TCM)

Traditional Chinese medicine (TCM) has been practiced for thousands of years with a recent increase in popularity. Despite promising biological activities of active ingredients and fractions from TCM, their poor solubility, poor stability, short biological half-life, ease of metabolism and rapid elimination hinder their clinical application. Therefore, overcoming these problems to improve the therapeutic efficacy of TCM preparations is a major focus of pharmaceutical sciences. Recently, nanocarriers have drawn increasing attention for their excellent and efficient delivery of active TCM ingredients or fractions. This review discusses problems in the delivery of active TCM ingredients or fractions; focuses on recent advances in nanocarriers that represent potential solutions to these problems, including lipid-based nanoparticles and polymeric, inorganic, and hybrid nanocarriers; and discusses unanswered questions in the field and criteria for the development of better nanocarriers for the delivery of active TCM ingredients or fractions to be focused on in future studies.

Formation of curcumin nanoparticles via solution-enhanced dispersion by supercritical CO2

In order to enhance the bioavailability of poorly water-soluble curcumin, solution-enhanced dispersion by supercritical carbon dioxide (CO2) (SEDS) was employed to prepare curcumin nanoparticles for the first time. A 2(4) full factorial experiment was designed to determine optimal processing parameters and their influence on the size of the curcumin nanoparticles. Particle size was demonstrated to increase with increased temperature or flow rate of the solution, or with decreased precipitation pressure, under processing conditions with different parameters considered. The single effect of the concentration of the solution on particle size was not significant. Curcumin nanoparticles with a spherical shape and the smallest mean particle size of 325 nm were obtained when the following optimal processing conditions were adopted: P = 20 MPa, T = 35°C, flow rate of solution = 0.5 mL·min(-1), concentration of solution = 0.5%. Fourier transform infrared (FTIR) spectroscopy measurement revealed that the chemical composition of curcumin basically remained unchanged. Nevertheless, X-ray powder diffraction (XRPD) and thermal analysis indicated that the crystalline state of the original curcumin decreased after the SEDS process. The solubility and dissolution rate of the curcumin nanoparticles were found to be higher than that of the original curcumin powder (approximately 1.4 μg/mL vs 0.2 μg/mL in 180 minutes). This study revealed that supercritical CO2 technologies had a great potential in fabricating nanoparticles and improving the bioavailability of poorly water-soluble drugs.

Nanocurcumin protects cardiomyoblasts H9c2 from hypoxia-induced hypertrophy and apoptosis by improving oxidative balance

Hypoxia-induced cardiomyocyte hypertrophy is evident; however, the distinct molecular mechanism underlying the oxidative stress-mediated damages to cardiomyocytes remains unknown. Curcumin (diferuloylmethane) is known for anti-hypertrophic effects, but low bioavailability makes it unsuitable to exploit its pharmacological properties. We assessed the efficacy of nanotized curcumin, i.e. nanocurcumin, in ameliorating hypoxia-induced hypertrophy and apoptosis in H9c2 cardiomyoblasts and compared it to curcumin. H9c2 cardiomyoblasts were challenged with 0.5 % oxygen, for 24 h to assess hypoxia-induced oxidative damage, hypertrophy and consequent apoptosis. The molecular mechanism underlying the protective efficacy of nanocurcumin was evaluated in regulating Raf-1/Erk-1/2 apoptosis by caspase-3/-7 pathway and oxidative stress. Nanocurcumin ameliorated hypoxia-induced hypertrophy and apoptosis in H9c2 cells significantly (p ≤ 0.01), by downregulating atrial natriuretic factor expression, caspase-3/-7 activation, oxidative stress and stabilizing hypoxia-inducible factor-1α (HIF-1α) better than curcumin. Nanocurcumin provides insight into its use as a potential candidate in curing hypoxia-induced cardiac pathologies by restoring oxidative balance.

Oral lipid-based nanoformulation of tafenoquine enhanced bioavailability and blood stage antimalarial efficacy and led to a reduction in human red blood cell loss in mice

Tafenoquine (TQ), a new synthetic analog of primaquine, has relatively poor bioavailability and associated toxicity in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals. A microemulsion formulation of TQ (MTQ) with sizes <20 nm improved the solubility of TQ and enhanced the oral bioavailability from 55% to 99% in healthy mice (area under the curve 0 to infinity: 11,368±1,232 and 23,842±872 min·μmol/L) for reference TQ and MTQ, respectively. Average parasitemia in Plasmodium berghei-infected mice was four- to tenfold lower in the MTQ-treated group. In vitro antiplasmodial activities against chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum indicated no change in half maximal inhibitory concentration, suggesting that the microemulsion did not affect the inherent activity of TQ. In a humanized mouse model of G6PD deficiency, we observed reduction in toxicity of TQ as delivered by MTQ at low but efficacious concentrations of TQ. We hereby report an enhancement in the solubility, bioavailibility, and efficacy of TQ against blood stages of Plasmodium parasites without a corresponding increase in toxicity.

Dried-leaf Artemisia annua: A practical malaria therapeutic for developing countries?

Artemisinin from the plant Artemisia annua (A. annua) L., and used as artemisinin combination therapy (ACT), is the current best therapeutic for treating malaria, a disease that hits children and adults especially in developing countries. Traditionally, A. annua was used by the Chinese as a tea to treat “fever”. More recently, investigators have shown that tea infusions and oral consumption of the dried leaves of the plant have prophylactic and therapeutic efficacy. The presence of a complex matrix of chemicals within the leaves seems to enhance both the bioavailability and efficacy of artemisinin. Although about 1000-fold less potent than artemisinin in their antiplasmodial activity, these plant chemicals are mainly small molecules that include other artemisinic compounds, terpenes (mainly mono and sesqui), flavonoids, and polyphenolic acids. In addition, polysaccharide constituents of A. annua may enhance bioavailability of artemisinin. Rodent pharmacokinetics showed longer T_½ and T_max and greater C_max and AUC in Plasmodium chabaudi-infected mice treated with A. annua dried leaves than in healthy mice. Pharmacokinetics of deoxyartemisinin, a liver metabolite of artemisinin, was more inhibited in infected than in healthy mice. In healthy mice, artemisinin serum levels were > 40-fold greater in dried leaf fed mice than those fed with pure artemisinin. Human trial data showed that when delivered as dried leaves, 40-fold less artemisinin was required to obtain a therapeutic response compared to pure artemisinin. ACTs are still unaffordable for many malaria patients, and cost estimates for A. annua dried leaf tablet production are orders of magnitude less than for ACT, despite improvements in the production capacity. Considering that for > 2000 years this plant was used in traditional Chinese medicine for treatment of fever with no apparent appearance of artemisinin drug resistance, the evidence argues for inclusion of affordable A. annua dried leaf tablets into the arsenal of drugs to combat malaria and other artemisinin-susceptible diseases.

Encapsulation of metalloporphyrins improves their capacity to block the viability of the human malaria parasite Plasmodium falciparum

Several synthetic metallated protoporphyrins (M-PPIX) were tested for their ability to block the cell cycle of the lethal human malaria parasite Plasmodium falciparum. After encapsulating the porphyrin derivatives in micro- and nanocapsules of marine atelocollagen, their effects on cultures of red blood cells infected (RBC) with P. falciparum were verified. RBCs infected with synchronized P. falciparum incubated for 48 h showed a toxic effect over a micromolar range. Strikingly, the IC50 of encapsulated metalloporphyrins reached nanomolar concentrations, where Zn-PPIX showed the best antimalarial effect, with an IC50=330 nM. This value is an 80-fold increase in the antimalarial activity compared to the antimalarial effect of non-encapsulated Zn-PPIX. These findings reveal that the incubation of P. falciparum infected-RBCs with 20 μM Zn-PPIX reduced the size of hemozoin crystal by 34%, whereas a 28% reduction was noticed with chloroquine, confirming the importance of heme detoxification pathway in drug therapy.

FROM THE CLINICAL EDITOR

In this study, synthetic metalloporphyrins were tested as therapeutics that target Plasmodium falciparum. The IC50 of encapsulated metalloporphyrins was found to be in the nanomolar concentration range, with encapsulated Zn-PPIX showing an 80-fold increase in its antimalarial activity compared to the non-encapsulated form.

Recombinant IκBα-loaded curcumin nanoparticles for improved cancer therapeutics

The field of recombinant protein therapeutics has been evolving rapidly, making significant impact on clinical applications for several diseases, including cancer. However, the functional aspects of proteins rely exclusively on their structural integrity, in which nanoparticle mediated delivery offers unique advantages over free proteins. In the present work, a novel strategy has been developed where the nanoparticles (NPs) used for the delivery of the recombinant protein could contribute to enhancing the therapeutic efficacy of the recombinant protein. The transcription factor, NFκB, involved in cell growth and its inhibitor, IκBα, regulates its proliferation. Another similar naturally available molecule, which inhibits the function of NFκB, is curcumin. Hence, we have developed a 'green synthesis' method for preparing water-soluble curcumin nanoparticles to stabilize recombinant IκBα protein. The NPs were characterized by UV-vis and fluorescence spectroscopy, transmission electron microscopy (TEM) and dynamic light scattering before administration into human cervical carcinoma (HeLa) and glioblastoma (U87MG) cells. Experimental results demonstrated that this combined module had enhanced therapeutic efficacy, causing apoptotic cell death, which was confirmed by cytotoxicity assay and flowcytometry analyses. The expression of apoptotic genes studied by semi-quantitative reverse transcription PCR delineated the molecular pathways involved in cell death. Thus, our study revealed that the functional delivery of recombinant IκBα-loaded curcumin NPs has promise as a natural-product-based protein therapeutics against cancer cells.

Transferrin-targeted polymeric micelles co-loaded with curcumin and paclitaxel: efficient killing of paclitaxel-resistant cancer cells

PURPOSE

The ability to successfully treat advanced forms of cancer remains a challenge due to chemotherapy resistance. Numerous studies indicate that NF-κB, a protein complex that controls the expression of numerous genes, as being a key factor in producing chemo-resistant tumors. In this study, the therapeutic potential of transferrin (TF)-targeted mixed micelles, made of PEG-PE and vitamin E co-loaded with curcumin (CUR), a potent NF-κB inhibitor, and paclitaxel (PCL), was examined.

METHODS

The cytotoxicity of non-targeted and TF-targeted CUR and PCL micelles as a single agent or in combination was investigated against SK-OV-3 human ovarian adenocarcinoma along with its multi-drug resistant (MDR) version SK-OV-3-PCL-resistant (SK-OV-3TR) cells in vitro.

RESULTS

Our results indicated that the TF-targeted combination micelles were able to improve the net cytotoxic effect of CUR and PCL to clear synergistic one against the SK-OV-3 cells. In addition, even though the non-targeted combination treatment demonstrated a synergistic effect against the SK-OV-3TR cells, the addition of the TF-targeting moiety significantly increased this cytotoxic effect. While keeping CUR constant at 5 and 10 μM and varying the PCL concentration, the PCL IC50 decreased from ~1.78 to 0.68 μM for the non-targeted formulations to ~0.74 and 0.1 μM for the TF-targeted ones, respectively.

CONCLUSION

Our results indicate that such co-loaded targeted mixed micelles could have significant clinical advantages for the treatment of resistant ovarian cancer and provide a clear rational for further in vivo investigation.

Nanotechnology-applied curcumin for different diseases therapy

Curcumin is a lipophilic molecule with an active ingredient in the herbal remedy and dietary spice turmeric. It is used by different folks for treatment of many diseases. Recent studies have discussed poor bioavailability of curcumin because of poor absorption, rapid metabolism, and rapid systemic elimination. Nanotechnology is an emerging field that is potentially changing the way we can treat diseases through drug delivery with curcumin. The recent investigations established several approaches to improve the bioavailability, to increase the plasma concentration, and to enhance the cellular permeability processes of curcumin. Several types of nanoparticles have been found to be suitable for the encapsulation or loading of curcumin to improve its therapeutic effects in different diseases. Nanoparticles such as liposomes, polymeric nanoparticles, micelles, nanogels, niosomes, cyclodextrins, dendrimers, silvers, and solid lipids are emerging as one of the useful alternatives that have been shown to deliver therapeutic concentrations of curcumin. This review shows that curcumin's therapeutic effects may increase to some extent in the presence of nanotechnology. The presented board of evidence focuses on the valuable special effects of curcumin on different diseases and candidates it for future clinical studies in the realm of these diseases.

Potential role of naturally derived polyphenols and their nanotechnology delivery in cancer

Polyphenols are natural compounds found in plants, fruits, chocolate, and beverages such as tea and wine. To date, the majority of polyphenol research shows them to have anticancer activity in cell lines and animal models. Some human clinical trials also indicate possible anticancer benefits are associated with polyphenols. A problem with polyphenols is their short half-life and low bioavailability; thus the use of nanoparticles to enhance their delivery is a new research field. A Pubmed search was conducted to find in vitro, in vivo, and human clinical trials done within the past 10 years involving the use of polyphenols against different cancer types, and for studies done within the past 5 years on the use of nanoparticles to enhance polyphenol delivery. Based on the studies found, it is observed that polyphenols may be a potential alternative or additive therapy against cancer, and the use of nanoparticles to enhance their delivery to tumors is a promising approach. However, further human clinical trials are necessary to better understand the use of polyphenols as well as their nanoparticle-mediated delivery.

Liposome encapsulation of curcumin: physico-chemical characterizations and effects on MCF7 cancer cell proliferation

The role of curcumin (diferuloylmethane), for cancer treatment has been an area of growing interest. However, due to its low absorption, the poor bioavailability of curcumin limits its clinical use. In this study, we reported an approach of encapsulation a curcumin by nanoliposome to achieve an improved bioavailability of a poorly absorbed hydrophobic compound. We demonstrated that liposomal preparations to deliver curcumin increase its bioavailability. Liposomes composed of salmon's lecithin also improved curcumin bioavailability compared to those constituted of rapeseed and soya lecithins. A real-time label-free cell analysis system based on real-time cell impedance monitoring was used to investigate the in vitro cytotoxicity of liposomal preparations.

Curcumin nanoformulations: a review of pharmaceutical properties and preclinical studies and clinical data related to cancer treatment

Curcumin, a natural yellow phenolic compound, is present in many kinds of herbs, particularly in Curcuma longa Linn. (turmeric). It is a natural antioxidant and has shown many pharmacological activities such as anti-inflammatory, anti-microbial, anti-cancer, and anti-Alzheimer in both preclinical and clinical studies. Moreover, curcumin has hepatoprotective, nephroprotective, cardioprotective, neuroprotective, hypoglycemic, antirheumatic, and antidiabetic activities and it also suppresses thrombosis and protects against myocardial infarction. Particularly, curcumin has demonstrated efficacy as an anticancer agent, but a limiting factor is its extremely low aqueous solubility which hampers its use as therapeutic agent. Therefore, many technologies have been developed and applied to overcome this limitation. In this review, we summarize the recent works on the design and development of nano-sized delivery systems for curcumin, including liposomes, polymeric nanoparticles and micelles, conjugates, peptide carriers, cyclodextrins, solid dispersions, lipid nanoparticles and emulsions. Efficacy studies of curcumin nanoformulations using cancer cell lines and in vivo models as well as up-to-date human clinical trials are also discussed.

Advances in nanomedicines for malaria treatment

Malaria is an infectious disease that mainly affects children and pregnant women from tropical countries. The mortality rate of people infected with malaria per year is enormous and became a public health concern. The main factor that has contributed to the success of malaria proliferation is the increased number of drug resistant parasites. To counteract this trend, research has been done in nanotechnology and nanomedicine, for the development of new biocompatible systems capable of incorporating drugs, lowering the resistance progress, contributing for diagnosis, control and treatment of malaria by target delivery. In this review, we discussed the main problems associated with the spread of malaria and the most recent developments in nanomedicine for anti-malarial drug delivery.

Anti-cancer activity of anti-GLUT1 antibody-targeted polymeric micelles co-loaded with curcumin and doxorubicin

BACKGROUND

Treatment of late stage cancers has proven to be a very difficult task. Targeted therapy and combinatory drug administration may be the solution.

PURPOSE

The study was performed to evaluate the therapeutic efficacy of PEG-PE micelles, co-loaded with curcumin (CUR) and doxorubicin (DOX), and targeted with anti-GLUT1 antibody (GLUT1) against HCT-116 human colorectal adenocarcinoma cells both in vitro and in vivo.

METHODS

HCT-116 cells were treated with non-targeted and GLUT1-targeted CUR and DOX micelles as a single agent or in combination. Cells were inoculated in female nude mice. Established tumors were treated with the micellar formulations at a dose of 4 mg/kg CUR and 0.4 mg/kg DOX every 2 d for a total of 7 injections.

RESULTS

CUR + DOX-loaded micelles decorated with GLUT1 had a robust killing effect even at low doses of DOX in vitro. At the doses chosen, non-targeted CUR and CUR + DOX micelles did not exhibit any significant tumor inhibition versus control. However, GLUT1-CUR and GLUT1-CUR + DOX micelles showed a significant tumor inhibition effect with an improvement in survival.

CONCLUSION

We showed a dramatic improvement in efficacy between the non-targeted and GLUT1-targeted formulations both in vitro and in vivo. Hence, we confirmed that GLUT1-CUR + DOX micelles are effective and deserve further investigation.

Modulation of cerebral malaria by curcumin as an adjunctive therapy

Cerebral malaria is the most severe and rapidly fatal neurological complication of Plasmodium falciparum infection and responsible for more than two million deaths annually. The current therapy is inadequate in terms of reducing mortality or post-treatment symptoms such as neurological and cognitive deficits. The pathophysiology of cerebral malaria is quite complex and offers a variety of targets which remain to be exploited for better therapeutic outcome. The present review discusses on the pathophysiology of cerebral malaria with particular emphasis on scope and promises of curcumin as an adjunctive therapy to improve survival and overcome neurological deficits.

Treatment of Plasmodium chabaudi Parasites with Curcumin in Combination with Antimalarial Drugs: Drug Interactions and Implications on the Ubiquitin/Proteasome System

Antimalarial drug resistance remains a major obstacle in malaria control. Evidence from Southeast Asia shows that resistance to artemisinin combination therapy (ACT) is inevitable. Ethnopharmacological studies have confirmed the efficacy of curcumin against Plasmodium spp. Drug interaction assays between curcumin/piperine/chloroquine and curcumin/piperine/artemisinin combinations and the potential of drug treatment to interfere with the ubiquitin proteasome system (UPS) were analyzed. In vivo efficacy of curcumin was studied in BALB/c mice infected with Plasmodium chabaudi clones resistant to chloroquine and artemisinin, and drug interactions were analyzed by isobolograms. Subtherapeutic doses of curcumin, chloroquine, and artemisinin were administered to mice, and mRNA was collected following treatment for RT-PCR analysis of genes encoding deubiquitylating enzymes (DUBs). Curcumin was found be nontoxic in BALB/c mice. The combination of curcumin/chloroquine/piperine reduced parasitemia to 37% seven days after treatment versus the control group's 65%, and an additive interaction was revealed. Curcumin/piperine/artemisinin combination did not show a favorable drug interaction in this murine model of malaria. Treatment of mice with subtherapeutic doses of the drugs resulted in a transient increase in genes encoding DUBs indicating UPS interference. If curcumin is to join the arsenal of available antimalarial drugs, future studies exploring suitable drug partners would be of interest.

Promising interaction between nanoencapsulated lutein with low molecular weight chitosan: characterization and bioavailability of lutein in vitro and in vivo

This study aims to develop water-soluble low molecular weight chitosan (LMWC) nanoencapsules with lutein to improve its bioavailability. Lutein-LMWC nanoencapsules were prepared, characterized and bioavailability was studied in vitro and in vivo with lutein in mixed micelles (control). The particle size ranged between 80-600 nm, which was confirmed by Atomic Force Microscope. The interaction between LMWC and lutein in nanocencapsules by (1)H and (13)C NMR showed the essentiality of water molecules to hold the lutein between LMWC chains of nanoparticle with a reversible weak bond. Bioavailability of lutein (200 μM) in vitro showed that lutein-LMWC nanoencapsules was significantly higher (27.7%) than control. Postprandial lutein level in the plasma (54.5%), liver (53.9%) and eyes (62.8%) of mice fed on nanoencapsulated lutein were higher than the control. LMWC may serve as novel carrier for enhancing the lutein bioavailability and can be suggested as the better dietary compound in food and pharmaceutical applications.

Challenges of Curcumin Bioavailability: Novel Aerosol Remedies

Nanoparticles are promising aids for drug delivery for previously challenging diseases, and many incurable ones. Curcumin (diferuloylmethane) is a pleiotropic molecule having various target molecules in the body. Despite its effects, curcumin-based drugs are not readily available in the market because of their low bioavailability. Although dietary intake and knowledge about the potential of curcumin are high in countries like India, studies indicate that the bioavailability problem still persists. However, administration of curcumin through inhalation has received little consideration. In this review we discuss the potential of curcumin, approaches made to overcome the bioavailability challenges, and novel approaches that could be applied in order to deliver curcumin in a pressurized metered dose inhaler (pMDI).

Curcumin encapsulation in submicrometer spray-dried chitosan/Tween 20 particles

Optimal curcumin delivery for medicinal applications requires a drug delivery system that both solubilizes curcumin and prevents degradation. To achieve this, curcumin has been encapsulated in submicrometer chitosan/Tween 20 particles via a benchtop spray-drying process. Spray-drying parameters have been optimized using a Taguchi statistical approach to minimize particle size and to favor spheroid particles with smooth surfaces, as evaluated with scanning electron microscopy (SEM) imaging. Nearly spherical particles with 285 ± 30 nm diameter and 1.21 axial ratio were achieved. Inclusion of curcumin in the spray-drying solution results in complete encapsulation of curcumin within the chitosan/Tween 20 particles. Release studies confirm that curcumin can be released completely from the particles over a 2 h period.

Advances in nanotechnology-based delivery systems for curcumin

Curcumin (CUR), a bioactive component of turmeric, which is a commonly used spice and nutritional supplement, is isolated from the rhizomes of Curcuma longa Linn. (Zingiberaceae). In recent years, the potential pharmacological actions of CUR in inflammatory disorders, cardiovascular disease, cancer, Alzheimer’s disease and neurological disorders have been shown. However, the clinical application of CUR is severely limited by its main drawbacks such as instability, low solubility, poor bioavailability and rapid metabolism. Multifarious nanotechnology-based delivery approaches have been used to enhance the oral bioavailability, biological activity or tissue-targeting ability of CUR. This article reviews potential novel drug delivery systems for CUR including liposomes, polymeric nanoparticles, solid lipid nanoparticles, micelles, nanogels, nanosuspensions, nanoemulsions, complexes and dendrimer/dimer, which provide promising results for CUR to improve its biological activities.

Validity of silver, chitosan, and curcumin nanoparticles as anti-Giardia agents

This study was carried out to evaluate the anti parasitic potential of silver, chitosan, and curcumin nanoparticles as anti-Giardia agents. Non-treated infected control rats were inoculated with Giardia lamblia cysts in a dose of 2 × 10(5) cysts/rat. Experimental group was infected then treated with curcumin, curcumin nanoparticles, chitosan, chitosan nanoparticles, and silver nanoparticles as single or combined therapy. The number of Giardia cysts in stools and trophozoites in intestinal sections were detected. Toxicity of nanoparticles was evaluated by comparing hematological and histopathological parameters of the normal control group and treated non-infected control group. The amount of silver was also measured in the liver, kidney, small intestine, lung, and brain of rats treated with silver nanoparticles. The number of the parasites in stool and small intestinal sections decreased in treated infected rats compared with infected non-treated ones. The effect in the single therapy was better with nanoparticles, and the best effect was detected in nano-silver. The combined therapy gave better results than single. Combination between nanoparticles was better than the combination of nano-forms and native chitosan and curcumin. The best effect was detected in combinations of nano-silver and nano-chitosan but with no full eradication. In conclusion, the highest effect and complete cure was gained by combining the three nano-forms. The parasite was successfully eradicated from stool and intestine. None of the treatments exhibited any toxicity. Accumulated silver in different organs was within the safe limits.

Curcumin-arteether combination therapy of Plasmodium berghei-infected mice prevents recrudescence through immunomodulation

Earlier studies in this laboratory have shown the potential of artemisinin-curcumin combination therapy in experimental malaria. In a parasite recrudescence model in mice infected with Plasmodium berghei (ANKA), a single dose of alpha,beta-arteether (ART) with three oral doses of curcumin prevented recrudescence, providing almost 95% protection. The parasites were completely cleared in blood with ART-alone (AE) or ART+curcumin (AC) treatments in the short-term, although the clearance was faster in the latter case involving increased ROS generation. But, parasites in liver and spleen were not cleared in AE or AC treatments, perhaps, serving as a reservoir for recrudescence. Parasitemia in blood reached up to 60% in AE-treated mice during the recrudescence phase, leading to death of animals. A transient increase of up to 2-3% parasitemia was observed in AC-treatment, leading to protection and reversal of splenomegaly. A striking increase in spleen mRNA levels for TLR2, IL-10 and IgG-subclass antibodies but a decrease in those for INFγ and IL-12 was observed in AC-treatment. There was a striking increase in IL-10 and IgG subclass antibody levels but a decrease in INFγ levels in sera leading to protection against recrudescence. AC-treatment failed to protect against recrudescence in TLR2(-/-) and IL-10(-/-) animals. IL-10 injection to AE-treated wild type mice and AC-treated TLR2(-/-) mice was able to prolong survival. Blood from the recrudescence phase in AE-treatment, but not from AC-treatment, was able to reinfect and kill naïve animals. Sera from the recrudescence phase of AC-treated animals reacted with several parasite proteins compared to that from AE-treated animals. It is proposed that activation of TLR2-mediated innate immune response leading to enhanced IL-10 production and generation of anti-parasite antibodies contribute to protective immunity in AC-treated mice. These results indicate a potential for curcumin-based combination therapy to be tested for prevention of recrudescence in falciparum and relapse in vivax malaria.