An overview of the efficacy of inhaled curcumin: a new mode of administration for an old molecule

INTRODUCTION

Curcumin is a polyphenol with a variety of pharmacological actions. Despite its therapeutic effects and well-known safety profile, the utility of curcumin has been limited due to its deprived physical, chemical, and pharmacokinetic profile resulting from limited solubility, durability, prompt deterioration and pitiable systemic availability. Employment of an amalgamated framework integrating the potential advantages of a nanoscaffold alongside the beneficial traits of inhalational drug delivery system beautifully bringing down the restricting attributes of intended curative interventions and further assures its clinical success.

AREAS COVERED

Current review discussed different application of inhalable nanocurcumin in different medical conditions. Lung diseases have been the prime field in which inhalable nanocurcumin had resulted in significant beneficial effects. Apart from this several lung protective potentials of the inhaled nanocurcumin have been discussed against severe pulmonary disorders such as pulmonary fibrosis, radiation pneumonitis and IUGR induced bronchopulmonary dysplasia. Also, application of the disclosed intervention in the clinical management of COVID-19 and Alzheimer's Disease has been discussed.

EXPERT OPINION

In this portion, the potential of inhalable nanocurcumin in addressing various medical conditions along with ongoing advancements in nanoencapsulation techniques and the existing challenges in transitioning from pre-clinical models to clinical practice has been summarized.

Anti-Inflammatory and Analgesic Effects of Curcumin Nanoparticles Associated with Diclofenac Sodium in Experimental Acute Inflammation

The present study evaluated the anti-inflammatory and analgesic effects of conventional curcumin (cC) and curcumin nanoparticles (nC) associated with diclofenac sodium (D) in experimental acute inflammation (AI) induced by carrageenan administration. Seven groups of eight randomly selected Wistar-Bratislava white rats were evaluated. One group was the control (C), and AI was induced in the other six groups. The AI group was treated with saline solution, the AID group was treated with D, the AIcC200 and AInC200 groups were treated with cC and nC, respectively, while AIcC200D and AInC200D were treated with cC and nC, respectively, both associated with D. Conventional curcumin, nC, and D were administered in a single dose of 200 mg/kg b.w. for cC and nC and 5 mg/kg b.w. for D. Association of cC or nC to D resulted in significant antinociceptive activity, and improved mechanical pressure stimulation and heat thresholds at 3, 5, 7 and 24 h (p < 0.03). The association of cC and nC with D (AIcC200D and AInC200D groups) showed significantly lower plasma and tissue levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) up to 2.5 times, with the best results in the group who received nC. Moreover, AInC200D presented the least severe histopathological changes with a reduced level of inflammation in the dermis and hypodermis. The combination of nC to D showed efficiency in reducing pain, inflammatory cytokines, and histological changes in acute inflammation.

Drug Delivery Strategies for Curcumin and Other Natural Nrf2 Modulators of Oxidative Stress-Related Diseases

Oxidative stress is associated with a wide range of diseases characterised by oxidant-mediated disturbances of various signalling pathways and cellular damage. The only effective strategy for the prevention of cellular damage is to limit the production of oxidants and support their efficient removal. The implication of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in the cellular redox status has spurred new interest in the use of its natural modulators (e.g., curcumin, resveratrol). Unfortunately, most natural Nrf2 modulators are poorly soluble and show extensive pre-systemic metabolism, low oral bioavailability, and rapid elimination, which necessitates formulation strategies to circumvent these limitations. This paper provides a brief introduction on the cellular and molecular mechanisms involved in Nrf2 modulation and an overview of commonly studied formulations for the improvement of oral bioavailability and in vivo pharmacokinetics of Nrf2 modulators. Some formulations that have also been studied in vivo are discussed, including solid dispersions, self-microemulsifying drug delivery systems, and nanotechnology approaches, such as polymeric and solid lipid nanoparticles, nanocrystals, and micelles. Lastly, brief considerations of nano drug delivery systems for the delivery of Nrf2 modulators to the brain, are provided. The literature reviewed shows that the formulations discussed can provide various improvements to the bioavailability and pharmacokinetics of natural Nrf2 modulators. This has been demonstrated in animal models and clinical studies, thereby increasing the potential for the translation of natural Nrf2 modulators into clinical practice.

Optical spectroscopy study of the interaction between curcumin and acrylic polymers

This paper presents the results of a study conducted on the interaction between curcumin, a compound with several biomedical applications in traditional and modern medicine, and the acrylic polymers poly(methyl methacrylate), poly(ethyl methacrylate), and poly(n-butyl methacrylate), through photophysical experiments in curcumin/acrylic polymers casting films. Optical absorption intensity at ~340 nm increases relatively to its maximum at ~417 nm when the amount of curcumin in the polymeric film decreases, due to a significant change in the concentration of the isomers cis- or trans-form of curcumin, regardless of the acrylic polymer. Fluorescence (FL) spectra of the films depend on the curcumin concentration in the matrix with well-resolved line shape. They show two distinct bands, one at ~525 nm, for higher curcumin concentration (5.00 mmol.L^-1), related to the aggregated curcumin species, and another at ~465 nm, for lower concentration of curcumin (0.10 mmol.L^-1), related to the effects of the solvent on the conformational structure of the curcumin molecule and the presence of the trans-form of curcumin. The parameter K_agg, related to the contribution of the aggregated curcumin, shows the influence of the polymeric lateral chain length of the matrix in the de-aggregation of the curcumin. The Huang-Rhys factor indicates that curcumin aggregated species are conformationally more stable, and that the isolate species depends on the chemical environment and the matrix/curcumin interaction, decreasing its conformational degrees of freedom. Arrhenius plots, obtained via FL experiment in function of the sample temperature, show that, for higher curcumin concentration, the value for the relaxation energy process is not well defined, due the decrease in the interaction between the matrix and the curcumin molecules. With these results, it is possible to infer that the interaction matrix/curcumin must occur via lateral chemical alkyl groups.

Development and Evaluation of Tannic Acid-Coated Nanosuspension for Enhancing Oral Bioavailability of Curcumin

Curcumin (CUR) has been used in the treatment of various diseases such as cough, fever, skin disease, and infection because of various biological benefits such as anti-inflammatory, antiviral, antibacterial, and antitumor activity. However, CUR is a BCS class 4 group and has a limitation of low bioavailability due to low solubility and permeability. Therefore, the purpose of this study is to prepare a nanosuspension (NSP) loaded with CUR (CUR-NSP) using a statistical design approach to improve the oral bioavailability of CUR, and then to develop CUR-NSP coated with tannic acid to increase the mucoadhesion in the GI tract. Firstly, the optimized CUR-NSP, composed of sodium dodecyl sulfate (SDS) and polyvinylpyrrolidone/vinyl acetate (PVP/VA), was modified with tannic acid (TA). The particle size and polydispersity index of the formulation measured by laser scattering analyzer were 127.7 ± 1.3 nm and 0.227 ± 0.010, respectively. In addition, the precipitation in distilled water (DW) was 1.52 ± 0.58%. Using a differential scanning calorimeter and X-ray diffraction analysis, the stable amorphous form of CUR was confirmed in the formulation, and it was confirmed that CUR-NSP formulation was coated with TA through a Fourier transform-infrared spectroscopy. In the mucoadhesion assay using the turbidity, it was confirmed that TA-CUR-NSP had higher affinity for mucus than CUR-NSP under all pH conditions. This means that the absorption of CUR can be improved by increasing the retention time in the GI tract of the formulation. In addition, the drug release profile showed more than 80% release, and in the cellular uptake study, the absorption of the formulation (TA-CUR-NSP) containing TA acting as an inhibitor of P-gp was increased by 1.6-fold. In the evaluation of antioxidant activity, the SOD activity of TA-CUR-NSP was remarkably high due to TA, which improves cellular uptake and has antioxidant activity. In the pharmacokinetic evaluation, the maximum drug plasma concentration of the TA-coated NSP formulation was 7.2-fold higher than that of the pure drug. In all experiments, it was confirmed that the TA-CUR-NSP is a promising approach to overcome the low oral bioavailability of CUR.

The Effect of Curcumin Nanoparticles on Cisplatin-Induced Cardiotoxicity in Male Wistar Albino Rats

The cardiotoxicity of chemotherapeutic drugs as cisplatin has become a major issue in recent years. The present study investigates the efficacy of curcumin nanoparticles against the cardiotoxic effects of cisplatin by assessment of oxidative stress parameters, Na+,K+-ATPase, acetylcholinesterase (AchE) and tumor necrosis factor-alpha (TNF-α) in cardiac tissue in addition to serum lactate dehydrogenase (LDH). Rats were divided into three groups: control rats that received saline for 14 days; cisplatin-treated rats that received a single intraperitoneal (i.p.) injection of cisplatin (12 mg/kg) followed by a daily oral administration of saline (0.9%) for 14 days and rats treated with a single i.p. injection of cisplatin (12 mg/kg) followed by a daily oral administration of curcumin nanoparticles (50 mg/kg) for 14 days. Cisplatin resulted in a significant increase in lipid peroxidation, nitric oxide (NO), and TNF-α and a significant decrease in reduced glutathione (GSH) levels and Na+, K+- ATPase activity. Moreover, significant increases in cardiac AchE and serum lactate dehydrogenase activities were recorded. Treatment of cisplatin-injected animals with curcumin nanoparticles ameliorated all the alterations induced by cisplatin in the heart of rats. This suggests that curcumin nanoparticles can be used as an important therapeutic adjuvant in chemotherapeutic and other toxicities mediated by oxidative stress and inflammation.

Curcumin nanoformulations for antimicrobial and wound healing purposes

The development and spread of resistance to antimicrobial drugs is hampering the management of microbial infectious and wound healing processes. Curcumin is the most active and effective constituent of Curcuma longa L., also known as turmeric, and has a very long and strong history of medicinal value for human health and skincare. Curcumin has been proposed as strong antimicrobial potentialities and many attempts have been made to determine its ability to conjointly control bacterial growth and promote wound healing. However, low aqueous solubility, poor tissue absorption and short plasma half-life due its rapid metabolism needs to be solved for made curcumin formulations as suitable treatment for wound healing. New curcumin nanoformulations have been designed to solve the low bioavailability problem of curcumin. Thus, in the present review, the therapeutic applications of curcumin nanoformulations for antimicrobial and wound healing purposes is described.

Protective Effects of Liposomal Curcumin on Oxidative Stress/Antioxidant Imbalance, Metalloproteinases 2 and -9, Histological Changes and Renal Function in Experimental Nephrotoxicity Induced by Gentamicin

BACKGROUND

Our study aimed to assess the efficiency of Curcumin nanoformulation (LCC) on experimental nephrotoxicity induced by Gentamicin in rats.

METHODS

Six groups of seven rats were used: C-(control group) received saline solution i.p. (i.p. = intraperitoneal), G-gentamicin (G, 80 mg/kg body weight (b.w.)), GCC1 and GCC2-with G and CC solution (single dose of 10 mg/kg b.w.-CC1, or 20 mg/kg b.w.-CC2), GLCC1 (10 mg/kg b.w.) and GLCC2 (20 mg/kg b.w.) with G and LCC administration. Oxidative stress parameters (NOx = nitric oxide, MDA = malondialdehyde, TOS = total oxidative stress), antioxidant parameters (CAT = catalase, TAC = total antioxidant capacity), matrix metalloproteinases (MMP-2 and MMP-9), and renal function parameters (creatinine, blood urea nitrogen, and urea) were measured. Kidneys histopathologic examination was made for each group.

RESULTS

Pretreatment with CC and LCC in both doses had significantly alleviating effects on assessed parameters (NOx, MDA, TOS, CAT, TAC, MMP-2, and -9) as compared with the untreated group (p < 0.006). Histopathological aspect and renal function were significantly improved in CC and LCC groups. Liposomal formulation (LCC) showed higher efficiency on all examined parameters compared to CC (p < 0.006).

CONCLUSIONS

Our results demonstrated improving renal function and kidney cytoarchitecture, oxidative stress/antioxidant/balance, and MMPs plasma concentrations with better dose-related efficacity of LCC than CC.

Enhancing Bioavailability and Stability of Curcumin Using Solid Lipid Nanoparticles (CLEN): A Covenant for Its Effectiveness

Curcumin, very rightly referred to as "a wonder drug" is proven to be efficacious in a variety of inflammatory disorders including cancers. Antiaging, anti-inflammatory, antioxidant, antitumor, chemosensitizing, P-gp efflux inhibiting, and antiproliferative activity are some of the striking features of curcumin, highlighting its importance in chemotherapy. Curcumin inhibits Bcl-2, Bcl-XL, VEGF, c-Myc, ICAM-1, EGFR, STAT3 phosphorylation, and cyclin D1 genes involved in the various stages of breast, prostate, and gastric cancer proliferation, angiogenesis, invasion, and metastasis. The full therapeutic potential of curcumin however remains under explored mainly due to poor absorption, rapid metabolism and systemic elimination culminating in its poor bioavailability. Furthermore, curcumin is insoluble, unstable at various pH and is also prone to undergo photodegradation. Nanotechnology can help improve the therapeutic potential of drug molecules with compromised biopharmaceutical profiles. Solid lipid nanoparticles (SLNs) are the latest offshoot of nanomedicine with proven advantages of high drug payload, longer shelf life, biocompatibility and biodegradability, and industrial amenability of the production process. We successfully developed CLEN (Curcumin encapsulated lipidic nanoconstructs) containing 15 mg curcumin per ml of the SLN dispersion with highest (till date, to our knowledge) increase in solubility of curcumin in an aqueous system by 1.4 × 106 times as compared to its intrinsic solubility of 11 ng/ml and high drug loading (15% w/v with respect to lipid matrix). Zero-order release kinetics observed for CLEN versus first order release for free curcumin establish controlled release nature of the developed CLEN. It showed 69.78 times higher oral bioavailability with respect to free curcumin; 9.00 times higher than a bioavailable marketed formulation (CurcuWIN®). The formulation showed 104, 13.3, and 10-times enhanced stability at pH 6.8, 1.2, and 7.4, respectively. All these factors ensure the efficacy of CLEN in treating cancer and other inflammatory diseases.

Comparative Effect of Curcumin and Nanocurcumin on Nephroprotection at Cisplatin-induced Rats

Background:

Cisplatin is a first-line chemotherapeutic agent for various solid tumors including ovarian and breast cancer. Thereby, it has been proven effective as an antineoplastic agent, but its clinically use is limited because of its nephrotoxicity side effect.

Aims and Objectives:

This study aimed to investigate curcumin as a renoprotector agent against cisplatin nephrotoxicity.

Materials and Methods:

The samples used were curcumin and its nanoparticles formulated using ionic gelation method. The nephrotoxicity was investigated through several parameters such as serum creatinine, blood urea nitrogen, serum albumin, kidney weight ratio, and histopathology. These parameters were tested on rats and divided into the following four groups: normal group, negative control group that administered cisplatin with doses amount of 7 mg/kg body weight (BW) intraperitoneally, nanocurcumin group (cisplatin + nanocurcumin) and curcumin group (cisplatin + curcumin). The agents were administered at a dose of 100 mg/kg BW every day in 9 days before cisplatin administration. The sample of blood serum and kidneys organ were taken 48h after cisplatin administration.

Results:

The negative control group showed a significant increase in serum creatinine, blood urea nitrogen, and kidney weight ratio, whereas it showed a significant decrease in serum albumin. The administration of sample agents showed a significant decrease in serum creatinine, blood urea nitrogen, and kidney weight ratio and an increase in the albumin level as compared to negative control group.

Conclusion:

Nanocurcumin showed significant improvement in kidneys more than curcumin. In contrast, histopathological examination verified the necrosis in negative control group, suggesting the renoprotection effect of nanocurcumin against nephrotoxicity on cisplatin-induced rats.

Curcumin Nanoparticles Protect against Isoproterenol Induced Myocardial Infarction by Alleviating Myocardial Tissue Oxidative Stress, Electrocardiogram, and Biological Changes

Curcumin from Curcuma longa is a nutraceutical compound reported to possess strong antioxidant activity that makes it a candidate for use in counteracting oxidative stress-induced damage. The effect of pre-treatment with curcumin nanoparticles (nC) compared to conventional curcumin (Cs) on blood pressure, electrocardiogram, and biological changes on isoproterenol (ISO)-induced myocardial infarction (MI) in rats had been investigated. The Cs doses of 150 and 200 mg/kg bw and all nC doses (100, 150 and 200 mg/kg bw) significantly reduced heart rate before ISO administration and prevented QRS complex enlargement after MI induction (p < 0.026). All doses of Cs and nC prevented prolongation of the QT and QT corrected (QTc) intervals, with better results for higher doses (p < 0.048). The nC solution had more significant results than Cs in all metabolic parameters assessed (lactate dehydrogenase, glycaemia, aspartate transaminase, and alanine transaminase, p < 0.009). nC was more efficient than Cs in limiting myocardial oxidative stress and enhancing antioxidative capacity (p < 0.004). Compared to Cs, nC better prevented myocardial damage extension, reduced interstitial oedema, and inflammation. Curcumin nanoparticles as compared to conventional curcumin exert better antioxidative effects. Moreover, nC better prevent cardiomyocytes damage, and electrocardiogram alterations, in the case of ISO-induced MI in rats.

Effects of Curcumin Nanoparticles in Isoproterenol-Induced Myocardial Infarction

Curcumin has anti-inflammatory, antioxidative, anticarcinogenic, and cardiovascular protective effects. Our study is aimed at evaluating the effects of pretreatment with curcumin nanoparticles (CCNP) compared to conventional curcumin (CC) on isoproterenol (ISO) induced myocardial infarction (MI) in rats. Fifty-six Wistar-Bratislava white rats were randomly divided into eight groups of seven rats each. Curcumin and curcumin nanoparticles were given by gavage in three different doses (100 mg/kg body weight (bw), 150 mg/kg bw, and 200 mg/kg bw) for 15 days. The MI was induced on day 13 using 100 mg/kg bw ISO administered twice, with the second dose 24 h after the initial dose. The blood samples were taken 24 h after the last dose of ISO. The antioxidant, anti-inflammatory, and cardioprotective effects were evaluated in all groups. All doses of CC and CCNP offered a cardioprotective effect by preventing creatine kinase-MB leakage from cardiomyocytes, with the best result for CCNP. All the oxidative stress parameters were significantly improved after CCNP compared to CC pretreatment. CCNP was more efficient than CC in limiting the increase in inflammatory cytokine levels (such as TNF-α, IL-6, IL-1α, IL-1β, MCP-1, and RANTES) after MI. MMP-2 and MMP-9 levels decreased more after pretreatment with CCNP than with CC. CCNP better prevented myocardial necrosis and reduced interstitial edema and neutrophil infiltration than CC, on histopathological examination. Therefore, improving the bioactivity of curcumin by nanotechnology may help limit cardiac injury after myocardial infarction.

Effects of polymer-coated boron nitrides with increased hemorheological compatibility on human erythrocytes and blood coagulation

BACKGROUND

Boron nitride (BN) nanomaterials are promising in biomedical research owing to their large surface area, graphene-like structure, and chemical and thermal properties. However, the toxicological effects of BN on erythrocytes and blood coagulation remain uninvestigated.

OBJECTIVE

The aims of our study were to synthesize glycol chitosan (GC)- and hyaluronic acid (HA)-coated BNs, and to investigate the effects of these BNs on human cancer cells, erythrocytes, and whole blood.

METHODS

We prepared hemocompatible forms of BN coated with GC and HA, and evaluated them using cell uptake/viability tests, hemolysis analysis and FE-SEM, as well as through hemorheological evaluation methods such as RBC deformability and aggregation, and blood coagulation.

RESULTS

GC/BN and HA/BN were both ∼200 nm, were successfully taken into cells, and emitted blue fluorescence. Both BNs were less toxic than bare BN, even at higher concentrations. The aggregation index of human red blood cells (RBCs) after 2 h incubation with BN, GC/BN, and HA/BN was greatly influenced, whereas RBC deformability did not dramatically change.

CONCLUSIONS

We found that GC/BN affected the intrinsic coagulation pathway, whereas both GC/BN and HA/BN affected the extrinsic pathway. Therefore, HA/BN is less detrimental to RBCs and blood coagulation dynamics than bare BN and GC/BN.

Injectable Nanocurcumin-Formulated Chitosan-g-Pluronic Hydrogel Exhibiting a Great Potential for Burn Treatment

Burn wound healing is a complex multifactorial process that relies on coordinated signaling molecules to succeed. Curcumin is believed to be a potent antioxidant and anti-inflammatory agent; therefore, it can prevent the prolonged presence of oxygen free radicals which is a significant factor causing inhabitation of optimum healing process. This study describes an extension of study about the biofunctional nanocomposite hydrogel platform that was prepared by using curcumin and an amphiphilic chitosan-g-pluronic copolymer specialized in burn wound healing application. This formular (nCur-CP, nanocomposite hydrogel) was a free-flowing sol at ambient temperature and instantly converted into a nonflowing gel at body temperature. In addition, the storage study determined the great stability level of nCur-CP in long time using UV-Vis and DLS. Morphology and distribution of nCur in its nanocomposite hydrogels were observed by SEM and TEM, respectively. In vitro studies suggested that nCur-CP exhibited well fibroblast proliferation and ability in antimicrobacteria. Furthermore, second- and third-degree burn wound models were employed to evaluate the in vivo wound healing activity of the nCur-CP. In the second-degree wound model, the nanocomposite hydrogel group showed a higher regenerated collagen density and thicker epidermis layer formation. In third degree, the nCur-CP group also exhibited enhancement of wound closure. Besides, in both models, the nanocomposite material-treated groups showed higher collagen content, better granulation, and higher wound maturity. Histopathologic examination also implied that the nanocomposite hydrogel based on nanocurcumin and chitosan could enhance burn wound repair. In conclusion, the biocompatible and injectable nanocomposite scaffold might have great potential to apply for wound healing.

The potential effect of garlic extract and curcumin nanoparticles against complication accompanied with experimentally induced diabetes in rats

BACKGROUND

Modified herbal medicines implicate the combination of several therapeutic practices of native systems of medicine that may extend many earlier generations, which frequently afford valuable therapeutic benefits.

PURPOSE

In this study, the role of nano-curcumin and aged garlic extract (AGE) as two modified phytomedicines on alleviating both of advanced glycation end products (AGEPs) and oxidative stress (OS) in streptozotocin (STZ) induced diabetic rats were investigated during this study.

METHOD

Nano-curcumin and AGE suspension were orally administrated at a dose of 300, 500 mg/kg body weight respectively. Serum glucose, insulin, total cholesterol, triglycerides and myocardial enzyme activities including creatine kinase-isoenzyme (CK-MB), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) were determined biochemically, while quantitative real-time polymerase chain reaction (qRT-PCR)-test had been used to determine relative of manganese-superoxide dismutase (Mn-SOD) and receptor for advanced glycation end products (RAGE) gene expressions in the heart tissue of rats. Structure of rat's heart tissue was examined by histopathological analysis (H&E).

RESULTS

AGE increased the body weight and insulin concentration, while, it decreased serum glucose concentration, CK-MB, and LDH enzyme activities in comparing with the diabetic group. In addition, total cholesterol, triglycerides, and AST didn't show any significant changes in serum values of AGE compared to diabetic rats. Nano-curcumin suspension decreased the serum levels of triglycerides, CK- MB, LDH, and AST. While, there were non-significant changes in the body weight, glucose, insulin, and total cholesterol level of the same group compared with the STZ- untreated induced diabetic rats. The transcript quantity of manganese-superoxide dismutase gene (Mn-SOD) was highly accumulated (3.25 and 3.87-fold) in the heart tissue sample of the induced diabetic rats in response to both nano-Curcumin and AGE suspension respectively. While AGE was the most potent treatment where it caused down regulation of the receptor for advanced glycation end products gene (RAGE) expression (1.79-fold). Results of histopathological analyses under the light microscope showed restoring the structural integrity of the myocytes towards normalization in diabetic hearts treated with each of nano-curcumin and AGE suspension compared with the untreated diabetic heart samples.

CONCLUSION

Nano-curcumin and AGE suspension have a great therapeutic potential in the treatment of DCM, Diabetic cardiomyopathy, by attenuating cardiac inflammation, myocardial fibrosis, and programmed myocardial cell deaths through inhibiting OS and AGEPs accumulation in diabetic heart tissue. Furthermore, the hypoglycemic antioxidant properties of AGE resulted in more potent therapeutic effect than nano-curcumin in the treatment of diabetic hearts.

Comparative Oral Absorption of Curcumin in a Natural Turmeric Matrix with Two Other Curcumin Formulations: An Open-label Parallel-arm Study

Curcuminoids are the major bioactive molecules in turmeric, and poor bioavailability deters them from being the major components of many health and wellness applications. This study was conducted to assess the bioavailability of a completely natural turmeric matrix formulation (CNTMF) and compare its bioavailability with two other commercially available formulations, namely, curcumin with volatile oil (volatile oil formulation) and curcumin with phospholipids and cellulose (phospholipid formulation) in healthy human adult male subjects (15 each group) under fasting conditions. Each formulation was administrated orally as a single 500-mg dose in capsule form, and blood samples were analyzed by liquid chromatography mass spectrometry at various time intervals up to 24 h. The ingestion of the CNTMF was very well absorbed and resulted in a mean curcuminoids plasma C_max of 170.14 ng/mL (T_max  = 4 h) compared with 47.54 ng/mL and 69.63 ng/mL for the volatile oil (T_max  = 3 h) and phospholipid (T_max  = 2.25 h) formulations, respectively. The extent of absorption of total curcuminoids in the blood for the CNTMF was 6× greater than volatile oil formulation and 5× greater than phospholipids formulation. The results of this study indicate that curcumin in a natural turmeric matrix exhibited greater bioavailability than the two comparator products. Copyright © 2017 John Wiley & Sons, Ltd.

Selection and optimization of nano-formulation of P-glycoprotein inhibitor for reversal of doxorubicin resistance in COLO205 cells

OBJECTIVE

The prime objective of current work was to develop a strategy for preparation of combinational nano-formulation for reversal of drug resistance.

METHODS

As a model system, doxorubicin (DOX)-resistant COLO205 cells were developed and validated. From co-treatment studies with DOX, curcumin was selected as it reversed DOX-resistance at lowest concentration. In an attempt to increase its solubility, curcumin was encapsulated into hydroxypropyl-β-cyclodextrin (HP-β-CD). Here, we propose that presence of stabilizer overcomes its low encapsulation efficiency. Thus, we evaluated curcumin encapsulation in HP-β-CD in presence of different stabilizers and organic solvents. Finally, the effect of nanocurcumin with liposomal DOX was studied for reversal of resistance in COLO205 cells.

KEY FINDINGS

In the process encapsulation, selective optimization of organic solvent by freeze-drying was found to be appropriate among other methods. From optimization studies with different organic solvent (acetone and dichloromethane) and stabilizer [polyvinyl alcohol (PVA) and Pluronics], HP-β-CD-encapsulated curcumin prepared using acetone in PVA-stabilized dispersion increased encapsulation (60%) with size of ~40 nm. Prepared nano-curcumin reversed the DOX resistance effectively in combination with liposomal DOX.

CONCLUSIONS

Curcumin reversed DOX resistance in COLO205 cells at low concentration and enhanced curcumin encapsulation in HP-β-CD was noted in presence of PVA. Further, it was observed that prepared HP-β-CD-encapsulated curcumin is equi-efficacious to nano-dispersed curcumin.

Pluronic stabilized Fe3O4 magnetic nanoparticles for intracellular delivery of curcumin

Water-dispersible Pluronic stabilized Fe₃O₄ magnetic nanoparticles were developed for intracellular delivery of hydrophobic anticancer drug.

Passively Targeted Curcumin-Loaded PEGylated PLGA Nanocapsules for Colon Cancer Therapy In Vivo

Clinical applications of curcumin for the treatment of cancer and other chronic diseases have been mainly hindered by its short biological half-life and poor water solubility. Nanotechnology-based drug delivery systems have the potential to enhance the efficacy of poorly soluble drugs for systemic delivery. This study proposes the use of poly(lactic-co-glycolic acid) (PLGA)-based polymeric oil-cored nanocapsules (NCs) for curcumin loading and delivery to colon cancer in mice after systemic injection. Formulations of different oil compositions are prepared and characterized for their curcumin loading, physico-chemical properties, and shelf-life stability. The results indicate that castor oil-cored PLGA-based NC achieves high drug loading efficiency (≈18% w(drug)/w(polymer)%) compared to previously reported NCs. Curcumin-loaded NCs internalize more efficiently in CT26 cells than the free drug, and exert therapeutic activity in vitro, leading to apoptosis and blocking the cell cycle. In addition, the formulated NC exhibits an extended blood circulation profile compared to the non-PEGylated NC, and accumulates in the subcutaneous CT26-tumors in mice, after systemic administration. The results are confirmed by optical and single photon emission computed tomography/computed tomography (SPECT/CT) imaging. In vivo growth delay studies are performed, and significantly smaller tumor volumes are achieved compared to empty NC injected animals. This study shows the great potential of the formulated NC for treating colon cancer.

Curcumin Pharmacokinetic and Pharmacodynamic Evidences in Streptozotocin-Diabetic Rats Support the Antidiabetic Activity to Be via Metabolite(s)

This study measures the curcumin concentration in rat plasma by liquid chromatography and investigates the changes in the glucose tolerance and insulin sensitivity of streptozotocin-diabetic rats treated with curcumin-enriched yoghurt. The analytical method for curcumin detection was linear from 10 to 500 ng/mL. The C_max⁡ and the time to reach C_max⁡ (t_max⁡) of curcumin in plasma were 3.14 ± 0.9 μg/mL and 5 minutes (10 mg/kg, i.v.) and 0.06 ± 0.01 μg/mL and 14 minutes (500 mg/kg, p.o.). The elimination half-time was 8.64 ± 2.31 (i.v.) and 32.70 ± 12.92 (p.o.) minutes. The oral bioavailability was about 0.47%. Changes in the glucose tolerance and insulin sensitivity were investigated in four groups: normal and diabetic rats treated with yoghurt (NYOG and DYOG, resp.) and treated with 90 mg/kg/day curcumin incorporated in yoghurt (NC90 and DC90, resp.). After 15 days of treatment, the glucose tolerance and the insulin sensitivity were significantly improved in DC90 rats in comparison with DYOG, which can be associated with an increase in the AKT phosphorylation levels and GLUT4 translocation in skeletal muscles. These findings can explain, at least in part, the benefits of curcumin-enriched yoghurt to diabetes and substantiate evidences for the curcumin metabolite(s) as being responsible for the antidiabetic activity.