Properties, Extraction Methods, and Delivery Systems for Curcumin as a Natural Source of Beneficial Health Effects

Neuroprotective Effects of Curcumin in Neurodegenerative Diseases

Curcumin, a hydrophobic polyphenol extracted from the rhizome of Curcuma longa, is now considered a candidate drug for the treatment of neurological diseases, including Parkinson's Disease (PD), Alzheimer's Disease (AD), Huntington's Disease (HD), Multiple Sclerosis (MS), Amyotrophic Lateral Sclerosis (ALS), and prion disease, due to its potent anti-inflammatory, antioxidant potential, anticancerous, immunomodulatory, neuroprotective, antiproliferative, and antibacterial activities. Traditionally, curcumin has been used for medicinal and dietary purposes in Asia, India, and China. However, low water solubility, poor stability in the blood, high rate of metabolism, limited bioavailability, and little capability to cross the blood-brain barrier (BBB) have limited the clinical application of curcumin, despite the important pharmacological activities of this drug. A variety of nanocarriers, including liposomes, micelles, dendrimers, cubosome nanoparticles, polymer nanoparticles, and solid lipid nanoparticles have been developed with great success to effectively deliver the active drug to brain cells. Functionalization on the surface of nanoparticles with brain-specific ligands makes them target-specific, which should significantly improve bioavailability and reduce harmful effects. The aim of this review is to summarize the studies on curcumin and/or nanoparticles containing curcumin in the most common neurodegenerative diseases, highlighting the high neuroprotective potential of this nutraceutical.

The Nanotech Potential of Curcumin in Pharmaceuticals: An Overview

It is safe to use Curcumin as a cosmetic and therapeutic ingredient in pharmaceutical products. For the uses mentioned above and for fundamental research, it is essential to obtain pure Curcumin from plant sources. There is a requirement for effective extraction and purification techniques that adhere to green chemistry standards for efficiency improvement, process safety, and environmental friendliness. Several outstanding studies have looked into the extraction and purification of Curcumin. This review thoroughly covers the currently available curcumin extraction, synthesis, and transformation techniques. Additionally, Curcumin's poor solubility and low absorption in the human body have limited its potential for pharmaceutical use. However, recent developments in novel curcumin formulations utilizing nanotechnology delivery methods have provided new approaches to transport and maximize the human body's curcumin absorption efficiency. In this review, we explore the various curcumin nanoformulations and the potential medicinal uses of nano curcumin. Additionally, we review the necessary future research directions to recommend Curcumin as an excellent therapeutic candidate.

The effect of environmental stressors on the anticancer potential of Amaranthus hypochondriacus aqueous extracts and fractions

Some Amaranthus species have been shown to have pharmacological properties such as activity against cancer, and it is also used as a traditional herbal medicine in many rural parts of the world. The (3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide assay was used as a screening tool to determine the approximate cell viability inhibitory concentrations of methanol and aqueous crude extracts of Amaranthus spp. The extracts were screened using small-cell lung cancer (H69V), hepatocellular carcinoma (HepG2/C3A) and non-cancerous kidney cells (Vero) cell lines. Viability was assessed following exposure to a series of concentrations of each extract and A. hypochondriacus showed cytotoxicity of 70.55 µg/mL against H69V with a Si index of 1.8. The fractionated aqueous extract of 40 °C-treated A. hypochondriacus under well-watered conditions had a higher viability inhibition on H69V and Vero cell lines compared to the A. caudatus, A. cruentus and A. spinosus crude extracts. In conclusion, A. hypochondriacus could serve as a potential source of anticancer phytoconstituents for drug development.

Curcumin Electrochemistry-Antioxidant Activity Assessment, Voltammetric Behavior and Quantitative Determination, Applications as Electrode Modifier

Curcumin (CU) is a polyphenolic compound extracted from turmeric, a well-known dietary spice. Since it has been shown that CU exerts beneficial effects on human health, interest has increased in its use but also in its analysis in different matrices. CU has an antioxidant character and is electroactive due to the presence of phenolic groups in its molecule. This paper reviews the data reported in the literature regarding the use of electrochemical techniques for the assessment of CU antioxidant activity and the investigation of the voltammetric behavior at different electrodes of free or loaded CU on various carriers. The performance characteristics and the analytical applications of the electrochemical methods developed for CU analysis are compared and critically discussed. Examples of voltammetric investigations of CU interaction with different metallic ions or of CU or CU complexes with DNA as well as the CU applications as electrode modifiers for the enhanced detection of various chemical species are also shown.

Curcumin, inflammation, and neurological disorders: How are they linked?

Background

Despite the extensive research in recent years, the current treatment modalities for neurological disorders are suboptimal. Curcumin, a polyphenol found in Curcuma genus, has been shown to mitigate the pathophysiology and clinical sequalae involved in neuroinflammation and neurodegenerative diseases.

Methods

We searched PubMed database for relevant publications on curcumin and its uses in treating neurological diseases. We also reviewed relevant clinical trials which appeared on searching PubMed database using 'Curcumin and clinical trials'.

Results

This review details the pleiotropic immunomodulatory functions and neuroprotective properties of curcumin, its derivatives and formulations in various preclinical and clinical investigations. The effects of curcumin on neurodegenerative diseases such as Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), brain tumors, epilepsy, Huntington's disorder (HD), ischemia, Parkinson's disease (PD), multiple sclerosis (MS), and traumatic brain injury (TBI) with a major focus on associated signalling pathways have been thoroughly discussed.

Conclusion

This review demonstrates curcumin can suppress spinal neuroinflammation by modulating diverse astroglia mediated cascades, ensuring the treatment of neurological disorders.

Phosphatidylcholine (PCL) fortified nano-phytopharmaceuticals for improvement of therapeutic efficacy

Phytopharmaceuticals, derived from plants, are increasingly recognized for their potential therapeutic benefits. However, their effectiveness is often hindered by challenges such as poor bioavailability, stability, and targeted delivery. In this study, we aimed to address these limitations by developing PCL (phosphatidylcholine) fortified nano-phytopharmaceuticals to enhance therapeutic efficacy. PCL, a biocompatible and biodegradable polymer, was employed to encapsulate the phytopharmaceuticals, thereby improving their stability and bioavailability. The encapsulation process utilized nanoprecipitation, resulting in the formation of nanoparticles with controlled size and morphology. Various analytical techniques were employed to characterize the physicochemical properties of PCL fortified nano-phytopharmaceuticals, including dynamic light scattering, scanning electron microscopy, and Fourier-transform infrared spectroscopy. Furthermore, the release kinetics of encapsulated phytopharmaceuticals from PCL nanoparticles were evaluated, demonstrating sustained and controlled release profiles, essential for prolonged therapeutic effects. Cytotoxicity studies conducted on in vitro cell culture models confirmed the biocompatibility and non-toxic nature of the developed nano-phytopharmaceuticals. Additionally, in vivo studies were conducted to assess the therapeutic efficacy of PCL fortified nano-phytopharmaceuticals in animal models. The results showIased improved bioavailability, targeted tissue distribution, and enhanced therapeutic effects compared to free phytopharmaceuticals. Moreover, the developed nano-phytopharmaceuticals exhibited prolonged circulation time in the bloodstream, enabling improved drug delivery and reduced dosing frequency. This review highlights the promising potential of PCL fortified nano-phytopharmaceuticals as an effective approach for enhancing the therapeutic efficacy of phytopharmaceuticals. The improved stability, bioavailability, sustained release, and targeted delivery achieved through this formulation strategy offer promising opportunities for advancing plant-based therapies. See also the Graphical abstract(Fig. 1).

Pharmacokinetics of Curcumin Delivered by Nanoparticles and the Relationship with Antitumor Efficacy: A Systematic Review

Curcumin is a polyphenolic compound, derived from Curcuma longa, and it has several pharmacological effects such as antioxidant, anti-inflammatory, and antitumor. Although it is a pleiotropic molecule, curcumin's free form, which is lipophilic, has low bioavailability and is rapidly metabolized, limiting its clinical use. With the advances in techniques for loading curcumin into nanostructures, it is possible to improve its bioavailability and extend its applications. In this review, we gather evidence about the comparison of the pharmacokinetics (biodistribution and bioavailability) between free curcumin (Cur) and nanostructured curcumin (Cur-NPs) and their respective relationships with antitumor efficacy. The search was performed in the following databases: Cochrane, LILACS, Embase, MEDLINE/Pubmed, Clinical Trials, BSV regional portal, ScienceDirect, Scopus, and Web of Science. The selected studies were based on studies that used High-Performance Liquid Chromatography (HPLC) as the pharmacokinetics evaluation method. Of the 345 studies initially pooled, 11 met the inclusion criteria and all included studies classified as high quality. In this search, a variety of nanoparticles used to deliver curcumin (polymeric, copolymeric, nanocrystals, nanovesicles, and nanosuspension) were found. Most Cur-NPs presented negative Zeta potential ranging from -25 mV to 12.7 mV, polydispersion index (PDI) ranging from 0.06 to 0.283, and hydrodynamic diameter ranging from 30.47 to 550.1 nm. Selected studies adopted mainly oral and intravenous administrations. In the pharmacokinetics analysis, samples of plasma, liver, tumor, lung, brain, kidney, and spleen were evaluated. The administration of curcumin, in nanoparticle systems, resulted in a higher level of curcumin in tumors compared to free curcumin, leading to an improved antitumor effect. Thus, the use of nanoparticles can be a promising alternative for curcumin delivery since this improves its bioavailability.

Curcuma Longa Induces the Transcription Factor FOXP3 to Downregulate Human Chemokine CCR5 Expression and Inhibit HIV-1 Infection

HIV mutations occur frequently despite the substantial success of combination antiretroviral therapy, which significantly impairs HIV progression. Failure to develop specific vaccines, the occurrence of drug-resistant strains, and the high incidence of adverse effects due to combination antiviral therapy regimens call for novel and safer antivirals. Natural products are an important source of new anti-infective agents. For instance, curcumin inhibits HIV and inflammation in cell culture assays. Curcumin, the principal constituent of the dried rhizomes of Curcuma longa L. (turmeric), is known as a strong anti-oxidant and anti-inflammatory agent with different pharmacological effects. This work aims to assess curcumin's inhibitory effects on HIV in vitro and to explore the underpinning mechanism, focusing on CCR5 and the transcription factor forkhead box protein P3 (FOXP3). First, curcumin and the RT inhibitor zidovudine (AZT) were evaluated for their inhibitory properties. HIV-1 pseudovirus infectivity was determined by green fluorescence and luciferase activity measurements in HEK293T cells. AZT was used as a positive control that inhibited HIV-1 pseudoviruses dose-dependently, with IC50 values in the nanomolar range. Then, a molecular docking analysis was carried out to assess the binding affinities of curcumin for CCR5 and HIV-1 RNase H/RT. The anti-HIV activity assay showed that curcumin inhibited HIV-1 infection, and the molecular docking analysis revealed equilibrium dissociation constants of [Formula: see text]9.8[Formula: see text]kcal/mol and [Formula: see text]9.3[Formula: see text]kcal/mol between curcumin and CCR5 and HIV-1 RNase H/RT, respectively. To examine curcumin's anti-HIV effect and its mechanism in vitro, cell cytotoxicity, transcriptome sequencing, and CCR5 and FOXP3 amounts were assessed at different concentrations of curcumin. In addition, human CCR5 promoter deletion constructs and the FOXP3 expression plasmid pRP-FOXP3 (with an EGFP tag) were generated. Whether FOXP3 DNA binding to the CCR5 promoter was blunted by curcumin was examined using transfection assays employing truncated CCR5 gene promoter constructs, a luciferase reporter assay, and a chromatin immunoprecipitation (ChIP) assay. Furthermore, micromolar concentrations of curcumin inactivated the nuclear transcription factor FOXP3, which resulted in decreased expression of CCR5 in Jurkat cells. Moreover, curcumin inhibited PI3K-AKT activation and its downstream target FOXP3. These findings provide mechanistic evidence encouraging further assessment of curcumin as a dietary agent used to reduce the virulence of CCR5-tropic HIV-1. Curcumin-mediated FOXP3 degradation was also reflected in its functions, namely, CCR5 promoter transactivation and HIV-1 virion production. Furthermore, curcumin inhibition of CCR5 and HIV-1 might constitute a potential therapeutic strategy for reducing HIV progression.

Optimization of ethanol-modified subcritical water extraction of curcuminoids from turmeric (Curcuma longa L.) rhizomes: Comparison with conventional techniques

Subcritical solvent extraction (SSE) as ethanol-modified subcritical water extraction (SWE) was applied to extract curcuminoids from turmeric (Curcuma longa L.) rhizomes. RSM-CCD was employed to evaluate the influential factors including temperature (90-150 °C), flow rate (1-4 mL/min), and ethanol concentration (25-75 wt%) on the extraction yield. The optimum condition was 90 °C, 4 mL/min, and 25 wt% with the extraction yield of 4.12 wt% (db). Applying ethanol as a polarity-tuning parameter enabled operations at lower temperatures, which prevented thermal degradation. The SSE optimum experiment was compared with Soxhlet, ultrasound-assisted extraction (UAE) and conventional solvent extraction (CSE), both with the ethanol-water mixture (25 wt%). Their yields were 2.71, 0.85, and 0.84 wt% (db), respectively. The higher yield of SSE was related to the higher solubility of curcuminoids due to the more appropriate adjustment of solvent polarity by a decrease in the dielectric constant with a rise in the operating temperature.

Pharmacophore-Based Virtual Screening and In-Silico Explorations of Biomolecules (Curcumin Derivatives) of Curcuma longa as Potential Lead Inhibitors of ERBB and VEGFR-2 for the Treatment of Colorectal Cancer

The newly FDA-approved drug, Axitinib, is an effective therapy against RTKs, but it possesses severe adverse effects like hypertension, stomatitis, and dose-dependent toxicity. In order to ameliorate Axitinib's downsides, the current study is expedited to search for energetically stable and optimized pharmacophore features of 14 curcumin (1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,6-diene-3,5-dione) derivatives. The rationale behind the selection of curcumin derivatives is their reported anti-angiogenic and anti-cancer properties. Furthermore, they possessed a low molecular weight and a low toxicity profile. In the current investigation, the pharmacophore model-based drug design, facilitates the filtering of curcumin derivatives as VEGFR2 interfacial inhibitors. Initially, the Axitinib scaffold was used to build a pharmacophore query model against which curcumin derivatives were screened. Then, top hits from pharmacophore virtual screening were subjected to in-depth computational studies such as molecular docking, density functional theory (DFT) studies, molecular dynamics (MD) simulations, and ADMET property prediction. The findings of the current investigation revealed the substantial chemical reactivity of the compounds. Specifically, compounds S8, S11, and S14 produced potential molecular interactions against all four selected protein kinases. Docking scores of -41.48 and -29.88 kJ/mol for compounds S8 against VEGFR1 and VEGFR3, respectively, were excellent. Whereas compounds S11 and S14 demonstrated the highest inhibitory potential against ERBB and VEGFR2, with docking scores of -37.92 and -38.5 kJ/mol against ERBB and -41.2 and -46.5 kJ/mol against VEGFR-2, respectively. The results of the molecular docking studies were further correlated with the molecular dynamics simulation studies. Moreover, HYDE energy was calculated through SeeSAR analysis, and the safety profile of the compounds was predicted through ADME studies.

Curcumin and Its Derivatives as Potential Antimalarial and Anti-Inflammatory Agents: A Review on Structure-Activity Relationship and Mechanism of Action

Curcumin, one of the major ingredients of turmeric (Curcuma longa), has been widely reported for its diverse bioactivities, including against malaria and inflammatory-related diseases. However, curcumin's low bioavailability limits its potential as an antimalarial and anti-inflammatory agent. Therefore, research on the design and synthesis of novel curcumin derivatives is being actively pursued to improve the pharmacokinetic profile and efficacy of curcumin. This review discusses the antimalarial and anti-inflammatory activities and the structure-activity relationship (SAR), as well as the mechanisms of action of curcumin and its derivatives in malarial treatment. This review provides information on the identification of the methoxy phenyl group responsible for the antimalarial activity and the potential sites and functional groups of curcumin for structural modification to improve its antimalarial and anti-inflammatory actions, as well as potential molecular targets of curcumin derivatives in the context of malaria and inflammation.

Curcumin Formulations for Better Bioavailability: What We Learned from Clinical Trials Thus Far?

Curcumin has been credited with a wide spectrum of pharmacological properties for the prevention and treatment of several chronic diseases such as arthritis, autoimmune diseases, cancer, cardiovascular diseases, diabetes, hemoglobinopathies, hypertension, infectious diseases, inflammation, metabolic syndrome, neurological diseases, obesity, and skin diseases. However, due to its weak solubility and bioavailability, it has limited potential as an oral medication. Numerous factors including low water solubility, poor intestinal permeability, instability at alkaline pH, and fast metabolism contribute to curcumin's limited oral bioavailability. In order to improve its oral bioavailability, different formulation techniques such as coadministration with piperine, incorporation into micelles, micro/nanoemulsions, nanoparticles, liposomes, solid dispersions, spray drying, and noncovalent complex formation with galactomannosides have been investigated with in vitro cell culture models, in vivo animal models, and humans. In the current study, we extensively reviewed clinical trials on various generations of curcumin formulations and their safety and efficacy in the treatment of many diseases. We also summarized the dose, duration, and mechanism of action of these formulations. We have also critically reviewed the advantages and limitations of each of these formulations compared to various placebo and/or available standard care therapies for these ailments. The highlighted integrative concept embodied in the development of next-generation formulations helps to minimize bioavailability and safety issues with least or no adverse side effects and the provisional new dimensions presented in this direction may add value in the prevention and cure of complex chronic diseases.

Efficacy of 1-Year Cavacurmin® Therapy in Reducing Prostate Growth in Men Suffering from Lower Urinary Tract Symptoms

We aim to assess the effect of Cavacurmin^® on prostate volume (PV), lower urinary tract symptoms (LUTS) and micturition parameters in men after 1 year of therapy. From September 2020 to October 2021, data from 20 men with LUTS/benign prostatic hyperplasia and PV ≥40 mL who were on therapy with α1-adrenoceptor antagonists plus Cavacurmin^® were retrospectively compared with 20 men on only α1-adrenoceptor antagonists. Patients were evaluated at baseline and after 1 year using the International Prostate Symptom Score (IPSS), prostate-specific antigen (PSA), maximum urinary flow (Qmax) and PV. A Mann-Whitney U-test and Chi-square were used to assess the difference between the two groups. A comparison of paired data was performed with the Wilcoxon signed-rank test. Statistical significance was set at p-value < 0.05. There was no statistically significant difference in baseline characteristics between the two groups. At the 1-year follow-up, PV [55.0 (15.0) vs. 62.5 (18.0) mL, p = 0.04)], PSA [2.5 (1.5) ng/mL vs. 3.05 (2.7) vs. p = 0.009] and IPSS [13.5 (3.75) vs. 18 (9.25) p = 0.009] were significantly lower in the Cavacurmin^® group. Qmax was significantly higher in the Cavacurmin^® group [15.85 (2.9) vs. 14.5 (4.2), p = 0.022]. PV was reduced to 2 (5.75) mL in the Cavacurmin^® group from baseline, while it increased to 12 (6.75) mL in the α1-adrenoceptor antagonists group (p < 0.001). PSA decreased in the Cavacurmin^® group [-0.45 (0.55) ng/mL], whereas it increased in the α1-adrenoceptor antagonists group [0.5 (0.30) ng/mL, p < 0.001]. In conclusion, one-year Cavacurmin^® therapy was able to block prostate growth with a concomitant decrease in PSA value from baseline. The association of Cavacurmin^® with α1-adrenoceptor antagonists had a more beneficial effect compared to patients on α1-adrenoceptor antagonists alone but this needs further larger studies to be confirmed, particularly in the long-term.

AL-Johani N, Alarifi S, Afzal M. Cytotoxicity Mechanisms of Blue-Light-Activated Curcumin in T98G Cell Line: Inducing Apoptosis through ROS-Dependent Downregulation of MMP Pathways

We examined the photodynamic activation of Curcumin under blue light in glioblastoma T98G cells. The therapeutic effect of Curcumin, in both the absence and presence of blue light, was measured by the MTT assay and apoptosis progression using flow cytometry. Fluorescence imaging was carried out to evaluate Curcumin uptake. Photodynamic activation of Curcumin (10 µM), in the presence of blue light, enhanced its cytotoxic effect, resulting in the activation of ROS-dependent apoptotic pathways in T98G cells. The gene expression studies showed the expression of matrixes metalloproteinase 2 (MMP2) and 9 (MMP9) decrease with Curcumin (10 µM) under blue light exposure, indicating possible proteolytic mechanisms. Moreover, the cytometric appearance displayed that the expressions of NF-κB and Nrf2 were found to be increased upon exposure to blue light, which revealed a significant induction of expression of nuclear factor as a result of blue-light-induced oxidative stress and cell death. These data further demonstrate that Curcumin exhibited a photodynamic effect via induction of ROS-mediated apoptosis in the presence of blue light. Our results suggest that the application of blue light enhances the therapeutic efficacy of Curcumin in glioblastoma because of the phototherapeutic effect.

Curcumin-Loaded Platelet Membrane Bioinspired Chitosan-Modified Liposome for Effective Cancer Therapy

Cancer is a serious threat to human health, and chemotherapy for cancer is limited by severe side effects. Curcumin (CUR) is a commonly used natural product for antitumor treatment without safety concerns. However, low bioavailability and poor tumor accumulation are great obstacles for its clinical application. Our previous research has demonstrated that platelet membrane-camouflaged nanoparticles can efficiently ameliorate the in vivo kinetic characteristics and enhance the tumor affinity of payloads. Nevertheless, the antitumor efficiency of this formulation still needs to be thoroughly investigated, and its drug release behavior is limited. Herein, CUR-loaded platelet membrane bioinspired chitosan-modified liposome (PCLP-CUR) was constructed to improve CUR release. PCLP-CUR was shown to have long retention time, improved bioavailability, strong tumor targeting capacity and effective cellular uptake. The incorporation of chitosan enabled PCLP-CUR to release cargoes quickly under mild acidic tumor conditions, leading to more complete drug release and favoring subsequent treatment. Both in vitro and in vivo investigations showed that PCLP-CUR could significantly enhance the anticancer efficacy of CUR with minimal side effects through biomimetic membrane and chitosan modification. In summary, this developed delivery system can provide a promising strategy for tumor-targeting therapy and phytochemical delivery.

Possible Mechanisms of Oxidative Stress-Induced Skin Cellular Senescence, Inflammation, and Cancer and the Therapeutic Potential of Plant Polyphenols

As the greatest defense organ of the body, the skin is exposed to endogenous and external stressors that produce reactive oxygen species (ROS). When the antioxidant system of the body fails to eliminate ROS, oxidative stress is initiated, which results in skin cellular senescence, inflammation, and cancer. Two main possible mechanisms underlie oxidative stress-induced skin cellular senescence, inflammation, and cancer. One mechanism is that ROS directly degrade biological macromolecules, including proteins, DNA, and lipids, that are essential for cell metabolism, survival, and genetics. Another one is that ROS mediate signaling pathways, such as MAPK, JAK/STAT, PI3K/AKT/mTOR, NF-κB, Nrf2, and SIRT1/FOXO, affecting cytokine release and enzyme expression. As natural antioxidants, plant polyphenols are safe and exhibit a therapeutic potential. We here discuss in detail the therapeutic potential of selected polyphenolic compounds and outline relevant molecular targets. Polyphenols selected here for study according to their structural classification include curcumin, catechins, resveratrol, quercetin, ellagic acid, and procyanidins. Finally, the latest delivery of plant polyphenols to the skin (taking curcumin as an example) and the current status of clinical research are summarized, providing a theoretical foundation for future clinical research and the generation of new pharmaceuticals and cosmetics.

Therapeutic Effect of Curcumin on Metabolic Diseases: Evidence from Clinical Studies

Metabolic diseases have become a serious threat to human health worldwide. It is crucial to look for effective drugs from natural products to treat metabolic diseases. Curcumin, a natural polyphenolic compound, is mainly obtained from the rhizomes of the genus Curcuma. In recent years, clinical trials using curcumin for the treatment of metabolic diseases have been increasing. In this review, we provide a timely and comprehensive summary of the clinical progress of curcumin in the treatment of three metabolic diseases, namely type 2 diabetes mellitus (T2DM), obesity and non-alcoholic fatty liver disease (NAFLD). The therapeutic effects and underlying mechanisms of curcumin on these three diseases are presented categorically. Accumulating clinical evidence demonstrates that curcumin has good therapeutic potential and a low number of side effects for the three metabolic diseases. It can lower blood glucose and lipid levels, improve insulin resistance and reduce inflammation and oxidative stress. Overall, curcumin may be an effective drug for the treatment of T2DM, obesity and NAFLD. However, more high-quality clinical trials are still required in the future to verify its efficacy and determine its molecular mechanisms and targets.

The Formulation of Curcumin: 2-Hydroxypropyl-β-cyclodextrin Complex with Smart Hydrogel for Prolonged Release of Curcumin

Curcumin comes from the plant species Curcuma longa and shows numerous pharmacological activities. There are numerous curcumin formulations with gels or cyclodextrins in order to increase its solubility and bioavailability. This paper presents the formulation of complex of curcumin with 2-hydroxypropyl-β-cyclodextrin in a thermosensitive hydrogel, based on N-isopropylmethacrylamide and N-isopropylacrylamide with ethylene glycol dimethacrylate as a crosslinker. The product was characterized by chemical methods and also by FTIR, HPLC, DSC, SEM, XRD. The results show that synthesis was successfully done. With an increase in the quantity of crosslinker in the hydrogels, the starting release and the release rate of curcumin from the formulation of the complex with hydrogels decreases. The release rate of curcumin from the gel complex formulation is constant over time. It is possible to design a formulation that will release curcumin for more than 60 days. In order to determine the mechanism and kinetics of curcumin release, various mathematical models were applied by using the DDSolver package for Microsoft Excel application. The Korsmeyer-Peppas model best describes the release of curcumin from the gel formulation of the complex, while the values for the diffusion exponent (0.063-0.074) shows that mechanism of the release rate is based on diffusion.

Fabrication of Sustained Release Curcumin-Loaded Solid Lipid Nanoparticles (Cur-SLNs) as a Potential Drug Delivery System for the Treatment of Lung Cancer: Optimization of Formulation and In Vitro Biological Evaluation

The goal of current research was to develop a new form of effective drug, curcumin-loaded solid lipid nanoparticles (Cur-SLNs) and test its efficacy in the treatment of lung cancer. Different batches of SLNs were prepared by the emulsification-ultrasonication method. For the optimization of formulation, each batch was evaluated for particle size, polydispersity index (PI), zeta potential (ZP), entrapment efficiency (EE) and drug loading (DL). The formulation components and process parameters largely affected the quality of SLNs. The SLNs obtained with particle size, 114.9 ± 1.36 nm; PI, 0.112 ± 0.005; ZP, -32.3 ± 0.30 mV; EE, 69.74 ± 2.03%, and DL, 0.81 ± 0.04% was designated as an optimized formulation. The formulation was freeze-dried to remove excess water to improve the physical stability. Freeze-dried Cur-SLNs showed 99.32% of drug release and demonstrated a burst effect trailed by sustained release up to 120 h periods. The erythrocyte toxicity study of Cur-SLNs and its components demonstrated moderate hemolytic potential towards red blood cells (RBCs). The cytotoxic potential of the formulation and plain curcumin was estimated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against A549 cell line. After 48 h of incubation, Cur-SLNs demonstrated more cytotoxicity (IC₅₀ = 26.12 ± 1.24 µM) than plain curcumin (IC₅₀ = 35.12 ± 2.33 µM). Moreover, the cellular uptake of curcumin was found to be significantly higher from Cur-SLNs (682.08 ± 6.33 ng/µg) compared to plain curcumin (162.4 ± 4.2 ng/µg). Additionally, the optimized formulation was found to be stable over the period of 90 days of storage. Hence, curcumin-loaded SLNs can be prepared using the proposed cost effective method, and can be utilized as an effective drug delivery system for the treatment of lung cancer, provided in vivo studies warrant a similar outcome.

Equine Muscle Derived Mesenchymal Stem Cells Loaded with Water-Soluble Curcumin: Modulation of Neutrophil Activation and Enhanced Protection against Intracellular Oxidative Attack

We investigated the antioxidant potential of equine mesenchymal stem cells derived from muscle microbiopsies (mdMSCs), loaded by a water-soluble curcumin lysinate incorporated into hydroxypropyl-β-cyclodextrin (NDS27). The cell loading was rapid and dependent on NDS27 dosage (14, 7, 3.5 and 1 µM). The immunomodulatory capacity of loaded mdMSCs was evaluated by ROS production, on active and total myeloperoxidase (MPO) degranulation and neutrophil extracellular trap (NET) formation after neutrophil stimulation. The intracellular protection of loaded cells was tested by an oxidative stress induced by cumene hydroperoxide. Results showed that 10 min of mdMSC loading with NDS27 did not affect their viability while reducing their metabolism. NDS27 loaded cells in presence of 14, 7 µM NDS27 inhibited more intensively the ROS production, the activity of the MPO released and bound to the NET after neutrophil stimulation. Furthermore, loaded cells powerfully inhibited intracellular ROS production induced by cumene as compared to control cells or cyclodextrin-loaded cells. Our results showed that the loading of mdMSCs with NDS27 significantly improved their antioxidant potential against the oxidative burst of neutrophil and protected them against intracellular ROS production. The improved antioxidant protective capacity of loaded mdMSCs could be applied to target inflammatory foci involving neutrophils.

Functional bioactive compounds in ginger, turmeric, and garlic

Nutrition plays a very important role in the health promotion of individuals and brought about a global paradigm shift from pharmaceuticals to nutraceuticals. This is due to the high cost, non-availability, and side effects associated with the unregulated consumption of pharmaceuticals. Over the ages, nutraceuticals from food products were reported to contain bioactive compounds with great health and physiological benefits. This report reviews bioactive compounds in selected foods namely ginger (Zingiber officinale), turmeric (Curcuma longa), and garlic (Allium sativum) as potential natural therapeutics for ailments of cancer and heart-related diseases. Analytical profiles, functional activities, and characterization of these compounds were discussed with possible recommendations for the prospective treatment of diseases using these nutraceuticals.

Effects of Curcumin and Lactoferrin to Inhibit the Growth and Migration of Prostatic Cancer Cells

Prostate cancer remains one of the main causes of death for men worldwide. Despite recent advances in cancer treatment, patients develop resistance after an initial period of optimal efficacy. Nowadays, it is accepted that natural compounds can result in health benefits with a preventive or adjuvant effect. The purpose of this study was to evaluate the effects of curcumin (CU), a bioactive compound in the spice turmeric, and lactoferrin (LF), a natural glycoprotein with immunomodulatory properties, on DU145 and PC3. Prostate cancer cells were cultured with and without LF (175 μM) and CU (2.5 μg/mL and 5 μg/mL), alone and in combination. Cell viability, migration ability, death receptors (DRs), and integrins (α3, β1) gene expression were evaluated, as well as human annexin V quantification and Akt phosphorylation. Differences among cells group, defined according to the treatment used, were assessed with ANOVA. The results showed that the effects of CU and LF are different between the two prostatic cell lines analyzed. In DU145, a reduction in cell proliferation and migration is reported both in the presence of single and combined treatments. In PC3 cells, there is a significant reduction in proliferation in the presence of CU alone, while the inhibition of migration is mainly related to the LF treatment and its combination with CU, compared to untreated cells. Moreover, the reduction in gene expression of integrins and Akt pathway activation were observed mostly in the presence of the CU and LF combination, including the upregulation of DR and annexin V levels, with greater significance for the DU145 cells. In conclusion, our results suggest that CU and LF may have a potentially beneficial effect, mainly when administered in combination, leading to a reduction in cancer cells' aggressiveness.

Effects of water-soluble curcuminoid-rich extract in a solid dispersion form (CRE-SD) on the sperm characteristics, longevity and casein kinase II catalytic subunit alpha protein stability in chilled goat semen

The present study evaluated the effects of water-soluble curcuminoid-rich extract in a solid dispersion form (CRE-SD) on goat sperm qualities and sperm protein CSNK2A2 expression during liquid storage. Semen was collected from five fertile goats, using an artificial vagina. Ejaculates with a motility above 70% were cooled to 4 °C using TRIS-citric acid-fructose diluent with 10% egg yolk containing various concentrations of CRE-SD (0, 0.1, 1, 10 and 100 μg/mL). Chilled sperm were evaluated for sperm characteristics, casein kinase II catalytic subunit alpha (CSNK2A2) protein level and oxidative status up to 15 days. After 12 days of preservation, sperm motility, viability, acrosomal integrity and mitochondrial activity were significantly higher in the group preserved with 10 μg/mL CRE-SD as compared with the control group. Supplementation of CRE-SD at this concentration was also able to conserve the CSNK2A2 a significantly higher than that in control group until 9 days of cold storage, possibly by reducing oxidative stress. The molecular mass of the sperm CSNK2A2 protein detected in this study was 37 kDa; it was mostly located in the post-acrosomal region, midpiece and flagellum. These results demonstrate the possibility to use the CRE-SD as a natural antioxidant during liquid semen storage in goats.

Supercritical Fluid Extraction with CO2 of Curcuma longa L. in Comparison to Conventional Solvent Extraction

Curcuma longa L. is a traditional medicinal and spice plant containing a variety of lipophilic active substances with promising therapeutic properties. In this work, the solvent properties of supercritical carbon dioxide in a pressure and temperature range of 75–425 bar and 35–75 °C were investigated when Curcuma longa rhizomes were extracted. The three main curcuminoids, namely curcumin, demethoxycurcumin, and bisdemethoxycurcumin, together with the three main constituents of the essential oil, i.e., ar-turmerone, α-turmerone, and β-turmerone, were analyzed in the resulting extracts. For statistical evaluation, experiments were performed employing a full factorial design, in which flow rate, extraction time, and drug load were kept constant. Within the given conditions, the experimental design revealed an optimum yield of all aforementioned substances, when supercritical carbon dioxide extraction was performed at 425 bar and 75 °C. For comparison, solvent extracts using methanol and n-hexane were prepared and their main components were characterized using LC-MS. The stability of the extracts was monitored upon storage for 6 months at 22 and 40 °C under protection from light. The decomposition of individual compounds was mainly observed in the presence of residual water in the extracts.

Effectiveness of Curcumin in Reducing Self-Rated Pain-Levels in the Orofacial Region: A Systematic Review of Randomized-Controlled Trials

The aim was to systematically review randomized controlled trials (RCTs) that assessed the effectiveness of curcumin in reducing self-rated pain levels in the orofacial region (OFR). The addressed focused question was “Is curcumin effective in reducing self-rated pain levels in the OFR?”. Indexed databases (PubMed (National Library of Medicine), Scopus, EMBASE, MEDLINE (OVID), and Web of Science) were searched up to and including February 2022 using different keywords. The inclusion criteria were (a) original studies (RCTs) in indexed databases; and (b) studies assessing the role of curcumin in the management of pain in the OFR. The risk of bias was assessed using the Cochrane risk of bias tool. The pattern of the present systematic review was customized to primarily summarize the pertinent information. Nineteen RCTs were included. Results from 79% of the studies reported that curcumin exhibits analgesic properties and is effective in reducing self-rated pain associated with the OFR. Three studies had a low risk of bias, while nine and seven studies had a moderate and high risk of bias, respectively. Curcumin can be used as an alternative to conventional therapies in alleviating pain in the OFR. However, due to the limitations and risk of bias in the aforementioned studies, more high-quality RCTs are needed.

Curcumin and Intestinal Oxidative Stress of Pigs With Intrauterine Growth Retardation: A Review

Intrauterine growth restriction (IUGR) refers to the slow growth and development of a mammalian embryo/fetus or fetal organs during pregnancy, which is popular in swine production and causes considerable economic losses. Nutritional strategies have been reported to improve the health status and growth performance of IUGR piglets, among which dietary curcumin supplementation is an efficient alternative. Curcumin is a natural lipophilic polyphenol derived from the rhizome of Curcuma longa with many biological activities. It has been demonstrated that curcumin promotes intestinal development and alleviates intestinal oxidative damage. However, due to its low bioavailability caused by poor solubility, chemical instability, and rapid degradation, the application of curcumin in animal production is rare. In this manuscript, the structural-activity relationship to enhance the bioavailability, and the nutritional effects of curcumin on intestinal health from the aspect of protecting piglets from IUGR associated intestinal oxidative damage were summarized to provide new insight into the application of curcumin in animal production.

Relationship between Immune Cells, Depression, Stress, and Psoriasis: Could the Use of Natural Products Be Helpful?

Psoriasis is one of the most widespread chronic inflammatory skin diseases, affecting about 2%-3% of the worldwide adult population. The pathogenesis of this disease is quite complex, but an interaction between genetic and environmental factors has been recognized with an essential modulation of inflammatory and immune responses in affected patients. Psoriatic plaques generally represent the clinical psoriatic feature resulting from an abnormal proliferation and differentiation of keratinocytes, which cause dermal hyperplasia, skin infiltration of immune cells, and increased capillarity. Some scientific pieces of evidence have reported that psychological stress may play a key role in psoriasis, and the disease itself may cause stress conditions in patients, thus reproducing a vicious cycle. The present review aims at examining immune cell involvement in psoriasis and the relationship of depression and stress in its pathogenesis and development. In addition, this review contains a focus on the possible use of natural products, thus pointing out their mechanism of action in order to counteract clinical and psychological symptoms.

Curcumin: Biological Activities and Modern Pharmaceutical Forms

Curcumin (1,7-bis-(4-hydroxy-3-methoxyphenyl)-hepta-1,6-diene-3,5-dione) is a natural lipophilic polyphenol that exhibits significant pharmacological effects in vitro and in vivo through various mechanisms of action. Numerous studies have identified and characterised the pharmacokinetic, pharmacodynamic, and clinical properties of curcumin. Curcumin has an anti-inflammatory, antioxidative, antinociceptive, antiparasitic, antimalarial effect, and it is used as a wound-healing agent. However, poor curcumin absorption in the small intestine, fast metabolism, and fast systemic elimination cause poor bioavailability of curcumin in human beings. In order to overcome these problems, a number of curcumin formulations have been developed. The aim of this paper is to provide an overview of recent research in biological and pharmaceutical aspects of curcumin, methods of sample preparation for its isolation (Soxhlet extraction, ultrasound extraction, pressurised fluid extraction, microwave extraction, enzyme-assisted aided extraction), analytical methods (FTIR, NIR, FT-Raman, UV-VIS, NMR, XRD, DSC, TLC, HPLC, HPTLC, LC-MS, UPLC/Q-TOF-MS) for identification and quantification of curcumin in different matrices, and different techniques for developing formulations. The optimal sample preparation and use of an appropriate analytical method will significantly improve the evaluation of formulations and the biological activity of curcumin.

Hydrogels for modified-release drug delivery systems

Hydrogels for the modified-release drug delivery systems is a continuously growing area of interest for the pharmaceutical industry. According to the global market, the use of polymers in this area is projected to reach $31.4 million by 2027. This review discusses the recent advances and perspectives of hydrogel in drug delivery systems for oral, parenteral, nasal, topical, and ophthalmic. The search strategy did in January 2021, and it conducted an extensive database to identify studies published from January 2010 to December 2020.We described the main characteristic of the polymers to obtain an ideal hydrogel for a specific route of administration and the formulations that was a highlight in the literature. It concluded that the hydrogels are a set useful to decrease the number of doses, side effects, promote adhesion of patient and enhances the bioavailability of the drugs improving the safety and efficacy of the treatment.

Molecular Targets of Natural Compounds with Anti-Cancer Properties

Cancer is the second leading cause of death in humans. Despite rapid developments in diagnostic methods and therapies, metastasis and resistance to administrated drugs are the main obstacles to successful treatment. Therefore, the main challenge should be the diagnosis and design of optimal therapeutic strategies for patients to increase their chances of responding positively to treatment and increase their life expectancy. In many types of cancer, a deregulation of multiple pathways has been found. This includes disturbances in cellular metabolism, cell cycle, apoptosis, angiogenesis, or epigenetic modifications. Additionally, signals received from the microenvironment may significantly contribute to cancer development. Chemical agents obtained from natural sources seem to be very attractive alternatives to synthetic compounds. They can exhibit similar anti-cancer potential, usually with reduced side effects. It was reported that natural compounds obtained from fruits and vegetables, e.g., polyphenols, flavonoids, stilbenes, carotenoids and acetogenins, might be effective against cancer cells in vitro and in vivo. Several published results indicate the activity of natural compounds on protein expression by its influence on transcription factors. They could also be involved in alterations in cellular response, cell signaling and epigenetic modifications. Such natural components could be used in our diet for anti-cancer protection. In this review, the activities of natural compounds, including anti-cancer properties, are described. The influence of natural agents on cancer cell metabolism, proliferation, signal transduction and epigenetic modifications is highlighted.

Curcumin activation of nuclear factor E2-related factor 2 gene (Nrf2): Prophylactic and therapeutic effect in nonalcoholic steatohepatitis (NASH)

BACKGROUNDS

Modern dietary habits have been associated with Nonalcoholic Steatohepatitis (NASH). Curcumin is a natural herbal found to suppress cellular oxidative states and could be beneficial in NASH. This study investigates the effect of curcumin in an animal model of NASH.

MATERIALS AND METHODS

Fifty rats were allocated into five groups. Control, High Fat Diet (HFD), curcumin prophylactic (CP) and therapeutic (CT) groups. HFD regimen was given for 16 weeks. Curcumin was given along with HFD (prophylactic) or after establishment of the model for two weeks (therapeutic). Livers and blood samples were harvested for histological, biochemical, and molecular studies.

KEY FINDINGS

Livers from HFD groups showed vascular, inflammatory, cellular degenerative and fibrotic changes. The hepatic damage was reflected by the increased serum liver enzymes. HFD groups showed excessive fibrotic change. Interestingly, curcumin administration as prophylactic or therapeutic significantly preserved and/or restored liver structure. This was evidenced by the normalization of the liver enzymes, preservation and/or reversibility of cellular changes and the decrease of the stage of fibrosis. Nuclear factor E2-related factor 2 gene (Nrf2) expression showed no changes in the HFD groups, however it showed upregulation in curcumin treated groups. Thus, the protective and therapeutic effect of curcumin could be induced through upregulation of the Nrf2 gene. Curcumin has a beneficial prophylactic and therapeutic effect that could hinder the development and/or treat NASH in susceptible livers.

SIGNIFICANCE

Curcumin has a beneficial prophylactic and therapeutic effect that could hinder the development and/or treat NASH in susceptible livers.

Lipid Nanocarriers for Hyperproliferative Skin Diseases

Simple Summary

Different drugs, including antiproliferative and corticosteroids in general, are recommended for the treatment of hyperproliferative skin diseases (HSD). The effectiveness of many of these drugs is limited due to their low solubility in water and low penetration in the skin. The loading of these drugs in lipid nanocarriers, such as lipid nanoparticles and liposomes, has been considered as a successful solution to improve the drug bioavailability through the skin, to control their release kinetics and thus reduce the risk of potential side effects. In this work, we discuss the use of lipid nanocarriers loading drugs against HSD.

Abstract

Hyperproliferative skin diseases (HSD) are a group of diseases that include cancers, pre-cancerous lesions and diseases of unknown etiology that present different skin manifestations in terms of the degree and distribution of the injuries. Anti-proliferative agents used to treat these diseases are so diverse, including 5-aminolevulinic acid, 5-fluorouracil, imiquimod, methotrexate, paclitaxel, podophyllotoxin, realgar, and corticosteroids in general. These drugs usually have low aqueous solubility, which consequently decreases skin permeation. Thus, their incorporation in lipid nanocarriers has been proposed with the main objective to increase the effectiveness of topical treatment and reduce side effects. This manuscript aims to describe the advantages of using lipid nanoparticles and liposomes that can be used to load diversity of chemically different drugs for the treatment of HSD.

Aging and its treatment with vitamin C: a comprehensive mechanistic review

Aging and age-related disorders have become one of the prominent issue of world. Oxidative stress due to overproduction of reactive oxygen species is the most significant cause of aging. The aim of literature compilation was to elucidate the therapeutic effect of vitamin C against oxidative stress. Various mediators with anti-inflammatory and anti-oxidant properties might be probable competitors of vitamin C for the improvement of innovative anti-aging treatments. More attention has been paid to vitamin C due to its anti-oxidant property and potentially beneficial biological activities for inhibiting aging.Vitamin C acts as an antioxidant agent and free radical scavenger that can protect the cell from oxidative stress, disorganization of chromatin, telomere attrition, and prolong the lifetime. This review emphasizes mechanism of aging and various biomarkers that are directly related to aging and also focuses on the therapeutic aspect of vitamin C against oxidative stress and age-related disorders.

Nanotherapeutics and nanotheragnostics for cancers: properties, pharmacokinetics, biopharmaceutics, and biosafety

With the worldwide increasing rate of chronic diseases, such as cancer, the development of novel techniques to improve the efficacy of therapeutic agents is highly demanded. Nanoparticles are especially well suited to encapsulate drugs and other therapeutic agents, bringing additional advantages, such as less frequent dosage requirements, reduced side effects due to specific targeting, and therefore increased patient compliance. However, with the increasing use of nanoparticles and their recent launch on the pharmaceutical market it is important to achieve high quality control of these advanced systems. In this review, we discuss the properties of different nanoparticles, the pharmacokinetics, the biosafety issues of concern, and conclude with novel nanotherapeutics and nanotheragnostics for cancer drug delivery.

Pharmacological properties and underlying mechanisms of curcumin and prospects in medicinal potential

Curcumin, isolated from Curcuma longa L., is a fat-soluble natural compound that can be obtained from ginger plant tuber roots, which accumulative evidences have demonstrated that it can resist viral and microbial infection and has anti-tumor, reduction of blood lipid and blood glucose, antioxidant and removal of free radicals, and is active against numerous disorders various chronic diseases including cardiovascular, pulmonary, neurological and autoimmune diseases. In this article is highlighted the recent evidence of curcuminoids applied in sevral aspects of medical problem particular in COVID-19 pandemics. We have searched several literature databases including MEDLINE (PubMed), EMBASE, the Web of Science, Cochrane Library, Google Scholar, and the ClinicalTrials.gov website via using curcumin and medicinal properties as a keyword. All studies published from the time when the database was established to May 2021 was retrieved. This review article summarizes the growing confirmation for the mechanisms related to curcumin's physiological and pharmacological effects with related target proteins interaction via molecular docking. The purpose is to provide deeper insight and understandings of curcumin's medicinal value in the discovery and development of new drugs. Curcumin could be used in the prevention or therapy of cardiovascular disease, respiratory diseases, cancer, neurodegeneration, infection, and inflammation based on cellular biochemical, physiological regulation, infection suppression and immunomodulation.

Quality by Design Methodology Applied to Process Optimization and Scale up of Curcumin Nanoemulsions Produced by Catastrophic Phase Inversion

In the presented study, we report development of a stable, scalable, and high-quality curcumin-loaded oil/water (o/w) nanoemulsion manufactured by concentration-mediated catastrophic phase inversion as a low energy nanoemulsification strategy. A design of experiments (DoE) was constructed to determine the effects of process parameters on the mechanical input required to facilitate the transition from the gel phase to the final o/w nanoemulsion and the long-term effects of the process parameters on product quality. A multiple linear regression (MLR) model was constructed to predict nanoemulsion diameter as a function of nanoemulsion processing parameters. The DoE and subsequent MLR model results showed that the manufacturing process with the lowest temperature (25 °C), highest titration rate (9 g/minute), and lowest stir rate (100 rpm) produced the highest quality nanoemulsion. Both scales of CUR-loaded nanoemulsions (100 g and 500 g) were comparable to the drug-free optimal formulation with 148.7 nm and 155.1 nm diameter, 0.22 and 0.25 PDI, and 96.29 ± 0.76% and 95.60 ± 0.88% drug loading for the 100 g and 500 g scales, respectively. Photostability assessments indicated modest loss of drug (<10%) upon UV exposure of 24 h, which is appropriate for intended transdermal applications, with expected reapplication of every 6-8 h.

Curcumin: Modern Applications for a Versatile Additive

The recent development of several methods for extracting curcumin from the root of the plant Curcuma longa has led to intensified research on the properties of curcumin and its fields of application. Following the studies and the accreditation of curcumin as a natural compound with antifungal, antiviral, and antibacterial properties, new fields of application have been developed in two main directions—food and medical, respectively. This review paper aims to synthesize the fields of application of curcumin as an additive for the prevention of spoilage, safety, and quality of food. Simultaneously, it aims to present curcumin as an additive in products for the prevention of bacterial infections and health care. In both cases, the types of curcumin formulations in the form of (nano)emulsions, (nano)particles, or (nano)composites are presented, depending on the field and conditions of exploitation or their properties to be used. The diversity of composite materials that can be designed, depending on the purpose of use, leaves open the field of research on the conditioning of curcumin. Various biomaterials active from the antibacterial and antibiofilm point of view can be intuited in which curcumin acts as an additive that potentiates the activities of other compounds or has a synergistic activity with them.

Curcumin encapsulation in nanostructures for cancer therapy: A 10-year overview

Curcumin (CUR) is a phenolic compound present in some herbs, including Curcuma longa Linn. (turmeric rhizome), with a high bioactive capacity and characteristic yellow color. It is mainly used as a spice, although it has been found that CUR has interesting pharmaceutical properties, acting as a natural antioxidant, anti-inflammatory, antimicrobial, and antitumoral agent. Nonetheless, CUR is a hydrophobic compound with low water solubility, poor chemical stability, and fast metabolism, limiting its use as a pharmacological compound. Smart drug delivery systems (DDS) have been used to overcome its low bioavailability and improve its stability. The current work overviews the literature from the past 10 years on the encapsulation of CUR in nanostructured systems, such as micelles, liposomes, niosomes, nanoemulsions, hydrogels, and nanocomplexes, emphasizing its use and ability in cancer therapy. The studies highlighted in this review have shown that these nanoformulations achieved higher solubility, improved tumor cytotoxicity, prolonged CUR release, and reduced side effects, among other interesting advantages.

Polychemotherapy with Curcumin and Doxorubicin via Biological Nanoplatforms: Enhancing Antitumor Activity

Doxorubicin (DOX) is a well-known chemotherapeutic agent extensively applied in the field of cancer therapy. However, similar to other chemotherapeutic agents such as cisplatin, paclitaxel, docetaxel, etoposide and oxaliplatin, cancer cells are able to obtain chemoresistance that limits DOX efficacy. In respect to dose-dependent side effect of DOX, enhancing its dosage is not recommended for effective cancer chemotherapy. Therefore, different strategies have been considered for reversing DOX resistance and diminishing its side effects. Phytochemical are potential candidates in this case due to their great pharmacological activities. Curcumin is a potential antitumor phytochemical isolated from Curcuma longa with capacity of suppressing cancer metastasis and proliferation and affecting molecular pathways. Experiments have demonstrated the potential of curcumin for inhibiting chemoresistance by downregulating oncogene pathways such as MMP-2, TGF-β, EMT, PI3K/Akt, NF-κB and AP-1. Furthermore, coadministration of curcumin and DOX potentiates apoptosis induction in cancer cells. In light of this, nanoplatforms have been employed for codelivery of curcumin and DOX. This results in promoting the bioavailability and internalization of the aforementioned active compounds in cancer cells and, consequently, enhancing their antitumor activity. Noteworthy, curcumin has been applied for reducing adverse effects of DOX on normal cells and tissues via reducing inflammation, oxidative stress and apoptosis. The current review highlights the anticancer mechanism, side effects and codelivery of curcumin and DOX via nanovehicles.

Reductive metabolites of curcumin and their therapeutic effects

Curcumin, a secondary metabolite from the turmeric plant is one of the most promising natural products, which has been studied extensively for decades. It has demonstrated several pharmacological activities in vitro and in vivo. Various studies have indicated that the pharmacological activity of curcumin is contributed by its metabolites. The aim of this review is to present an overview of metabolic products of curcumin produced upon its reduction like di, tetra, hexa and octa-hydrocurcumin. In addition, this paper has systematically analyzed the current information regarding medicinal use of reduced metabolites of curcumin and identified the limitations which have hindered its widespread usage in the medical world. Several diverse therapeutic effects have shown to be exhibited by reduced metabolites of curcumin such as antioxidant, anti-cancerous, anti-inflammatory and immunoregulatory activities. The potential underlying molecular mechanisms of the biological activities of reduced metabolites of curcumin have also been highlighted, which may provide insight into the principle of effectiveness of curcumin.