TPGS-Stabilized Curcumin Nanoparticles Exhibit Superior Effect on Carrageenan-Induced Inflammation in Wistar Rat

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.

Anti-inflammatory and antioxidant effects of nanoformulations composed of metal-organic frameworks delivering rutin and/or piperine natural agents

Plant-derived natural medicines have been extensively studied for anti-inflammatory or antioxidant properties, but challenges to their clinical use include low bioavailability, poor solubility in water, and difficult-to-control release kinetics. Nanomedicine may offer innovative solutions that can enhance the therapeutic activity and control release kinetics of these agents, opening the way to translating them into the clinic. Two agents of particular interest are rutin (Ru), a flavonoid, and piperine (Pip), an alkaloid, which exhibit a range of pharmacological activities that include antioxidant and anti-inflammatory effects. In this work, nanoformulations were developed consisting of two metal–organic frameworks (MOFs) with surface modifications, Ti-MOF and Zr-MOF, each of them loaded with Ru and/or Pip. Both MOFs and nanoformulations were characterized and evaluated in vivo for anti-inflammatory and antioxidant effects. Loadings of ∼17 wt.% for a single pro-drug and ∼27 wt.% for dual loading were achieved. The release patterns for Ru and or Pip followed two stages: a zero-order for the first 12-hour stage, and a second stage of stable sustained release. At pH 7.4, the release patterns best fit to zero-order and Korsmeyer–Peppas kinetic models. The nanoformulations had enhanced anti-inflammatory and antioxidant effects than any of their elements singly, and those with Ru or Pip alone showed stronger effects than those with both agents. Results of assays using a paw edema model, leukocyte migration, and plasma antioxidant capacity were in agreement. Our preliminary findings indicate that nanoformulations with these agents exert better anti-inflammatory and antioxidant effects than the agents in their free form.

Fabrication and characterization of sunflower protein isolate nanoparticles, and their potential for encapsulation and sustainable release of curcumin

In this research, first, the effects of two desolvating agents (ethanol and methanol) at three temperature values (4, 25, and 50 °C) on the fabrication of sunflower protein isolate (SnPI) nanoparticles were studied using a desolvation method. Second, the ability of the nanoparticles to encapsulate curcumin was investigated. Results showed that ethanol led to smaller nanoparticles compared to methanol as the desolvating agent at 4 and 50 °C. However, at 25 °C, ethanol formed the most uniform nanoparticles with the lowest polydispersity index (0.188 ± 0.091) and particle size of 174.64 ± 30.61 nm. The encapsulation efficiency was in the range of 39.1 to 95.4% according to the fabrication condition and curcumin-to-protein mass ratio. A biphasic trend of curcumin release from nanoparticles was observed; in which, over 50% of curcumin was released from the curcumin-loaded nanoparticles in the first 2 h, which is attributed to the burst effect of the protein matrix.

Virucidal Action Against Avian Influenza H5N1 Virus and Immunomodulatory Effects of Nanoformulations Consisting of Mesoporous Silica Nanoparticles Loaded with Natural Prodrugs

Background

Combating infectious diseases caused by influenza virus is a major challenge due to its resistance to available drugs and vaccines, side effects, and cost of treatment. Nanomedicines are being developed to allow targeted delivery of drugs to attack specific cells or viruses.

Materials and Methods

In this study, mesoporous silica nanoparticles (MSNs) functionalized with amino groups and loaded with natural prodrugs of shikimic acid (SH), quercetin (QR) or both were explored as a novel antiviral nanoformulations targeting the highly pathogenic avian influenza H5N1 virus. Also, the immunomodulatory effects were investigated in vitro tests and anti-inflammatory activity was determined in vivo using the acute carrageenan-induced paw edema rat model.

Results

Prodrugs alone or the MSNs displayed weaker antiviral effects as evidenced by virus titers and plaque formation compared to nanoformulations. The MSNs-NH₂-SH and MSNs-NH₂-SH-QR2 nanoformulations displayed a strong virucidal by inactivating the H5N1 virus. They induced also strong immunomodulatory effects: they inhibited cytokines (TNF-α, IL-1β) and nitric oxide production by approximately 50% for MSNs-NH₂-SH-QR2 (containing both SH and QR). Remarkable anti-inflammatory effects were observed during in vivo tests in an acute carrageenan-induced rat model.

Conclusion

Our preliminary findings show the potential of nanotechnology for the application of natural prodrug substances to produce a novel safe, effective, and affordable antiviral drug.

Animal Models of Inflammation for Screening of Anti-inflammatory Drugs: Implications for the Discovery and Development of Phytopharmaceuticals

Inflammation is one of the common events in the majority of acute as well as chronic debilitating diseases and represent a chief cause of morbidity in today's era of modern lifestyle. If unchecked, inflammation leads to development of rheumatoid arthritis, diabetes, cancer, Alzheimer's disease, and atherosclerosis along with pulmonary, autoimmune and cardiovascular diseases. Inflammation involves a complex network of many mediators, a variety of cells, and execution of multiple pathways. Current therapy for inflammatory diseases is limited to the steroidal and non-steroidal anti-inflammatory agents. The chronic use of these drugs is reported to cause severe adverse effects like gastrointestinal, cardiovascular, and renal abnormalities. There is a massive need to explore new anti-inflammatory agents with selective action and lesser toxicity. Plants and isolated phytoconstituents are promising and interesting sources of new anti-inflammatories. However, drug development from natural sources has been linked with hurdles like the complex nature of extracts, difficulties in isolation of pure phytoconstituents, and the yield of isolated compounds in minute quantities that is insufficient for subsequent lead development. Although various in-vivo and in-vitro models for anti-inflammatory drug development are available, judicious selection of appropriate animal models is a vital step in the early phase of drug development. Systematic evaluation of phytoconstituents can facilitate the identification and development of potential anti-inflammatory leads from natural sources. The present review describes various techniques of anti-inflammatory drug screening with its advantages and limitations, elaboration on biological targets of phytoconstituents in inflammation and biomarkers for the prediction of adverse effects of anti-inflammatory drugs. The systematic approach proposed through present article for anti-inflammatory drug screening can rationalize the identification of novel phytoconstituents at the initial stage of drug screening programs.

The effect of surface treatment on the brain delivery of curcumin nanosuspension: in vitro and in vivo studies

Background: Curcumin, a bioactive component with multiple characteristics, has been shown to have many therapeutic effects. However, there are several limitations regarding the use of curcumin such as instability, low solubility, poor bioavailability, and rapid elimination. Different approaches have been used to solve these problems.

Materials and methods: In this study, surface-modified nanosuspension (NS) is investigated as a novel brain delivery system. Two different methods were used for the preparation of nanosuspensions with two different stabilizers. The surface of the nanosuspensions was coated with D-α-tocopheryl polyethylene glycol 1,000 succinate (TPGS) and Tween 80 using physical adsorption. Curcumin NSs were prepared using two different top-down techniques by high-pressure homogenizer and probe sonicator. A validated sensitive and selective high-performance liquid chromatography method using fluorescence detection was used for the determination and quantification of curcumin. Pharmacokinetics and biodistribution of curcumin NSs and solutions after intravenous administration in rats were studied.

Results: Higher levels of curcumin in the brain were detected when Tween 80-coated NS was used compared with the curcumin solution and TPGS coated NS (TPGS-NS) (P-value<0.05). Absorption of ApoE and/or B by Tween 80-coated nanoparticles (NPs) from the blood were caused transferring of these NPs into the brain using receptor-mediated endocytosis. Distribution of TPGS-NS in the brain compared with the curcumin solution was higher (P-value<0.05). Higher levels of curcumin concentration in the liver, spleen, and lung were also observed with TPGS-NS.

Conclusion: The results of this study indicate that the surface-coating of NSs by Tween 80 may be used to improve the biodistribution of curcumin in the brain.

Curcumin Combination Chemotherapy: The Implication and Efficacy in Cancer

Many chemotherapeutic drugs have been used for the treatment of cancer, for instance, doxorubicin, irinotecan, 5-fluorouracil, cisplatin, and paclitaxel. However, the effectiveness of chemotherapy is limited in cancer therapy due to drug resistance, therapeutic selectivity, and undesirable side effects. The combination of therapies with natural compounds is likely to increase the effectiveness of drug treatment as well as reduce the adverse outcomes. Curcumin, a polyphenolic isolated from Curcuma longa, belongs to the rhizome of Zingiberaceae plants. Studies from in vitro and in vivo revealed that curcumin exerts many pharmacological activities with less toxic effects. The biological mechanisms underlying the anticancer activity of co-treatment curcumin and chemotherapy are complex and worth to discuss further. Therefore, this review aimed to address the molecular mechanisms of combined curcumin and chemotherapy in the treatment of cancer. The anticancer activity of combined nanoformulation of curcumin and chemotherapy was also discussed in this study. Taken together, a better understanding of the implication and underlying mechanisms of action of combined curcumin and chemotherapy may provide a useful approach to combat cancer diseases.

Curcumin formulated in solid lipid nanoparticles has enhanced efficacy in Hodgkin's lymphoma in mice

Curcumin reduces Hodgkin's lymphoma (HL) cell growth in vitro, but its unfavorable pharmacokinetics highlight the need for novel in vivo delivery systems. Thus, we explored whether formulation of curcumin in solid lipid nanoparticles (SLN-curc) or d-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS) nanoparticles (TPGS-curc) could enhance its efficacy in mice. Curcumin formulated in SLN and in TPGS resulted in higher curcumin plasma levels in mice. Compared to vehicle-treated controls, SLN-curc and TPGS-curc reduced HL xenograft growth by 50.5% (p < 0.02) and 43.0% (p < 0.04), respectively, while curcumin reduced it by 35.8% (p < 0.05). In addition, SLN-curc reduced the expression of proteins involved in cell proliferation and apoptosis (XIAP and Mcl-1) in HL tumor extracts. In HL cells in culture, curcumin decreased the expression of relevant anti-inflammatory cytokines (IL-6 and TNF-α) in a concentration-dependent manner. Moreover, when given in combination with bleomycin, doxorubicin and vinblastine, curcumin showed an additive growth inhibitory effect. In conclusion, SLNs appear as an appropriate and effective drug delivery system for curcumin. Given the efficacy of SLN-curc and the enhanced growth inhibitory effect when combined with chemotherapeutic drugs, we speculate that curcumin, when appropriately formulated, is a promising adjuvant agent for the treatment of HL and merits further evaluation.

Multiple Functions of D-α-Tocopherol Polyethylene Glycol 1000 Succinate (TPGS) as Curcumin Nanoparticle Stabilizer: In Vivo Kinetic Profile and Anti-Ulcerative Colitis Analysis in Animal Model

This study was conducted to evaluate the potential benefit of particle reduction down to nanoscale on curcumin, a unique natural active compound facing therapeutic problems due to low solubility and permeability. In addition, the presence of TPGS as a surfactant for multiple functions on curcumin nanoparticle was addressed. Observation was focused on bioavailability enhancement after oral administration and local anti-inflammatory improvement after rectal dosing. Nanonization of curcumin was performed using an up-scalable top down method. Specific animal models were used to study the in vivo kinetic profile and the biological activity of curcumin nanoparticle, compared with curcumin powder. d-α-tocopherol polyethylene glycol 1000 succinate (TPGS)-stabilized curcumin nanoparticle was prepared through homogenization with high pressure of the 1500 bar. An in vivo study was performed after oral administration of the preparations to male healthy Wistar rats, to monitor the plasma kinetic profile of curcumin. The biological activity study was conducted after rectal administration of the preparations in Wistar rats induced by 2,4,6-trinitrobenzene sulfonic acid to develop ulcerative colitis. The curcumin nanoparticle with a size of approximately 200 nm was successfully produced and revealed a better in vivo kinetic profile over the larger size of curcumin mixed with TPGS, with bioavailability (AUC0-∞) that was accounted for seven-fold. In addition, the TPGS-stabilized curcumin nanoparticle demonstrated a superior local anti-inflammatory effect in ulcerative colitis, indicated by the shifting of observed parameters close to the healthy status. The tremendously improved anti-inflammatory effect of the TPGS-stabilized curcumin nanoparticle was found with a very low dose. Reducing the particle size of curcumin down to ~200 nm with the presence of TPGS seems to be a promising approach to improving the therapeutic value of curcumin.