Improving Curcumin Bioavailability: Current Strategies and Future Perspectives

Preparation and characterization of zein-caseinate-pectin complex nanoparticles for encapsulation of curcumin: pectin extracted by high-speed shearing from passion fruit (Passiflora edulis f. flavicarpa) peel

BACKGROUND

Pectin extracted by high-speed shearing from passion fruit peel (HSSP) is a potentially excellent wall material for encapsulating curcumin, which has multiple advantages over pectin prepared by heated water extraction. HSSP was used to fabricate complex nanoparticles of zein-sodium caseinate-pectin for encapsulation of curcumin in this study. The influence of heating on the physicochemical properties of the composite nanoparticles was also investigated, as well as the effect of composite nanoparticles on the encapsulation efficiency, antioxidant activity and release characteristics of curcumin.

RESULTS

The nanoparticles were formed through electrostatic interactions, hydrogen bonds and hydrophobic interactions between the proteins and HSSP. A temperature of 50 °C was more favorable for generating compact and small-sized nanoparticles, which could effectively improve the encapsulation efficiency and functional properties. Moreover, compared to other pectin used in the study, the nanoparticles prepared with HSSP showed the best functionality with a particle size of 234.28 ± 0.85 nm, encapsulation rate of 90.22 ± 0.54%, free radical scavenging rate of 78.97% and strongest protective capacity in simulated gastric fluid and intestinal release effect.

CONCLUSION

Zein-sodium caseinate-HSSP is effective for encapsulating and delivering hydrophobic bioactive substances such as curcumin, which has potential applications in the functional food and pharmaceutical industries. © 2024 Society of Chemical Industry.

Curcumin-loaded polymeric nanomaterials as a novel therapeutic strategy for Alzheimer's disease: A comprehensive review

Alzheimer's disease (AD) stands as a formidable challenge in modern medicine, characterized by progressive neurodegeneration, cognitive decline, and memory impairment. Despite extensive research, effective therapeutic strategies remain elusive. The antioxidant, anti-inflammatory, and neuroprotective properties of curcumin, found in turmeric, have demonstrated promise. The poor bioavailability and rapid systemic clearance of this drug limit its clinical application. This comprehensive review explores the potential of curcumin-loaded polymeric nanomaterials as an innovative therapeutic avenue for AD. It delves into the preparation and characteristics of diverse polymeric nanomaterial platforms, including liposomes, micelles, dendrimers, and polymeric nanoparticles. Emphasis is placed on how these platforms enhance curcumin's bioavailability and enable targeted delivery to the brain, addressing critical challenges in AD treatment. Mechanistic insights reveal how these nanomaterials modulate key AD pathological processes, including amyloid-beta aggregation, tau phosphorylation, oxidative stress, and neuroinflammation. The review also highlighted the preclinical studies demonstrate reduced amyloid-beta plaques and neuroinflammation, alongside improved cognitive function, while clinical trials show promise in enhancing curcumin's bioavailability and efficacy in AD. Additionally, it addresses the challenges of clinical translation, such as regulatory issues, large-scale production, and long-term stability. By synthesizing recent advancements, this review underscores the potential of curcumin-loaded polymeric nanomaterials to offer a novel and effective therapeutic approach for AD, aiming to guide future research and development in this field.

Gelatin-nanocellulose stabilized emulsion-filled hydrogel beads loaded with curcumin: Preparation, encapsulation and release behavior

In this study, the curcumin was firstly encapsulated in gelatin (GLT) and/or cellulose nanocrystals (CNC) stabilized emulsions, then further mixed with sodium alginate (SA) to form emulsion-filled hydrogel beads loaded with curcumin (Cur). The Cur-loaded emulsions showed a droplet size of 20.3-24.4 μm with a uniform distribution. Introducing CNC and/or SA increased the viscosity of emulsions accompanied by viscoelastic transition, while the modulus was reduced due to destruction of GLT gel. Cur was doubly immobilized in the hydrogel beads with >90 % of encapsulation efficiency. The results of simulated gastrointestinal tract experiments revealed that the beads possessed a good pH sensitivity and controlled release behavior to prolong the retention of Cur in the gastrointestinal tract. After 6 h of UV irradiation, the Cur-loaded emulsion-filled hydrogel beads showed a higher antioxidant activity than that of pure Cur, effectively delaying the photodegradation of Cur. In addition, the beads had better stability in aqueous and acidic environments, which was favorable for prolonging the release of Cur. These results suggest that the emulsion-filled hydrogel beads have great potential for the delivery of lipophilic bioactive molecules.

The effects of curcumin supplementation on biomarkers of inflammation, oxidative stress, and endothelial function: A meta-analysis of meta-analyses

Numerous interventional studies have revealed the beneficial impact of curcumin supplementation on inflammation, oxidative stress, and endothelial function biomarkers, but the findings are still inconsistent. Thus, this study was conducted to investigate the effects of curcumin supplementation on inflammation, oxidative stress, and endothelial function biomarkers. A meta-analyses of randomized clinical trials was performed by searching PubMed, Embase, Scopus, and Web of Science up to March 31, 2024. Pooled estimates of 21 meta-analyses revealed that curcumin significantly reduced CRP (weighted mean difference (WMD) = -0.87; 95 % CI: - 1.14, - 0.59, P< 0.001), tumor-necrosis factor-alpha (TNF-α) (WMD = -2.72; 95 % CI: -4.05, -1.38; P< 0.001), interleukin-6 (IL-6) (WMD = -0.97, 95 % CI: -1.40, -0.54; P< 0.001), malondialdehyde (MDA) (Effect size (ES) = -0.81; 95 % CI: -1.39, -0.23, P = 0.006) and pulse wave velocity (PWV) (WMD = -45.60; 95 % CI: -88.16, -3.04, P = 0.036), and increased flow-mediated dilation (FMD) (WMD = 1.64, 95 % CI: 1.06, 2.22, P < 0.001), catalase (CAT) (WMD = 10.26; 95 % CI: 0.92, 19.61, P= 0.03), glutathione peroxidase (GPx) (WMD = 8.90; 95 % CI: 6.62, 11.19, P <0.001), and superoxide dismutase (SOD) levels (WMD = 20.51; 95 % CI: 7.35, 33.67, P= 0.002 and SMD = 0.82; 95 % CI: 0.27, 1.38, P= 0.004). However, curcumin did not significantly change total antioxidant capacity (TAC) (ES = 0.29; 95 % CI: -0.09, 0.66, P= 0.059). These results suggest that curcumin has a beneficial effect on CRP, IL-6, TNF-α, SOD, GPx, CAT, MDA, PWV, and FMD levels and may be an effective adjunctive therapy for improving inflammation, oxidative stress, and endothelial function. Registration number: PROSPERO, CRD42024539018.

Anti-gouty arthritis and anti-inflammatory effects of curcumin nanoparticles in monosodium urate crystals induced Balb/C mice

Gout is a metabolic condition characterized by the accumulation of urate crystals in the synovial joints. These crystal depositions result in joint swelling and increased concentration of serum uric acid in blood. The commercially available drugs lower serum uric acid levels and reduce inflammation, but these standard therapies have many side effects. This study aimed to investigate anti-gout and anti-inflammatory properties of curcumin nanoparticles (CNPs). For this purpose, CNPs were prepared by dissolving curcumin into dichloromethane. Then, gout was induced by injecting monosodium urate crystals (MSU) in the ankle joint and in the intra-peritoneal cavity which caused ankle swelling and increased blood uric acid levels. CNPs in different concentrations (5, 10, and 20 ppm) and allopurinol were orally administered. The MSU crystals increased the xanthine oxidase levels both in serum and the liver. Moreover, MSU crystals increased the serum levels of interleukin 1β, interleukin-6, tumor necrosis factor-alpha, liver function tests markers, renal function tests markers, and lipid profiles. However, the administration of CNPs decreased the levels of all these variables. CNPs increased the serum high-density lipoprotein and interleukin-10 levels. Moreover, CNPs also reduced ankle swelling significantly. Hence, the levels of xanthine oxidase, uric acid and ankle swelling were reduced significantly by oral administration of CNPs. Our findings indicate that CNPs through their anti-inflammatory properties significantly alleviate gouty arthritis. Thus, the study concluded that CNPs can be developed as an efficient anti-gout agent with minimal side effects.

Turmeric: from spice to cure. A review of the anti-cancer, radioprotective and anti-inflammatory effects of turmeric sourced compounds

Turmeric (Curcuma longa) has been extensively studied for its diverse pharmacological properties, including its potential role as an anticancer agent, antioxidant, and radioprotector. This review provides an overview of the chemical composition of turmeric, focusing on its main bioactive compounds, such as curcuminoids and volatile oils. Curcumin, the most abundant curcuminoid in turmeric, has been widely investigated for its various biological activities, including anti-inflammatory, antioxidant, and anticancer effects. Numerous in vitro and in vivo studies have demonstrated the ability of curcumin to modulate multiple signaling pathways involved in carcinogenesis, leading to inhibition of cancer cell proliferation, induction of apoptosis, and suppression of metastasis. Furthermore, curcumin has shown promising potential as a radioprotective agent by mitigating radiation-induced oxidative stress and DNA damage. Additionally, turmeric extracts containing curcuminoids have been reported to exhibit potent antioxidant activity, scavenging free radicals and protecting cells from oxidative damage. The multifaceted pharmacological properties of turmeric make it a promising candidate for the development of novel therapeutic strategies for cancer prevention and treatment, as well as for the management of oxidative stress-related disorders. However, further research is warranted to elucidate the underlying mechanisms of action and to evaluate the clinical efficacy and safety of turmeric and its bioactive constituents in cancer therapy and radioprotection. This review consolidates the most recent relevant data on turmeric's chemical composition and its therapeutic applications, providing a comprehensive overview of its potential in cancer prevention and treatment, as well as in radioprotection.

Analgesic Potential Comparison Between Piperine-Combined Curcumin Patch and Non-Piperine Curcumin Patch: A Pragmatic Trial on Post-Cleft Lip/Palate Surgery Pediatric Patients

Purpose

Despite its well-acknowledged analgesic potential, curcumin's low bioavailability has been recognized. Piperine, a substance naturally contained in pepper, has been known for its effect on increasing curcumin bioavailability. To investigate the analgesic potential of curcumin and piperine addition to curcumin patch used as adjuvant therapy in the management of acute postoperative orofacial pain.

Patients and Methods

This pragmatic trial recruited 75 patients that underwent oromaxillofacial surgery at Unpad Dental Hospital, Bandung, Indonesia. Research participants were randomly assigned to three different groups: the first group that did not receive any intervention other than the post-operative standard treatment (POST), the second group that received POST and non-piperine curcumin patch, and the third group that received POST and piperine-combined curcumin patch. Participants' pain intensity was evaluated by using the face, leg, activity, cry, and consolability (FLACC) pain scale and salivary prostaglandin-E2 (PGE2) level for two-time points, which were eight hours apart. All data were gathered and analyzed to compare the within and between-group differences.

Results

Within groups comparison of the FLACC scores for two evaluation points showed significant differences for all groups (p < 0.01). For salivary PGE2 analysis, a comparison of the non-piperine group to the piperine group also showed significant results. Yet, when all three groups were compared, regardless of the differences, the results were not statistically significant.

Conclusion

Despite of the proven efficacy of curcumin patch, the addition of piperine to the curcumin patch in the current study did not provide any significant effects. Further investigation is of importance.

Unraveling the protective effects of curcumin against drugs of abuse

Curcumin, a natural compound derived from the turmeric plant (Curcuma longa), has garnered significant attention for its diverse neuroprotective properties. Curcumin has been widely recognized for its remarkable anti-inflammatory, antioxidant, and anti-apoptotic effects, which have shown great potential in the treatment of various disorders, encompassing psychiatric and neurodegenerative diseases. In this review, we delve into the protective effects of curcumin against drugs of abuse, including morphine, methamphetamine, cocaine, nicotine, and alcohol, with a particular focus on the underlying mechanisms from a neuroscience perspective. Overall, curcumin demonstrates promising effects against the neurotoxicity induced by abused drugs through a wide range of mechanisms. These include the modulation of inflammatory cytokines, maintenance of ion homeostasis, epigenetic regulation, enhancement of antioxidant capacity, as well as the activation of the cAMP response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) signaling pathways. These findings suggest that curcumin emerges as a promising therapeutic agent in combatting the detrimental effects induced by drugs of abuse, and further research is warranted to fully comprehend the molecular pathways and optimize its utilization for the prevention and treatment of substance abuse-related neurotoxicity.

Stability and gastrointestinal behavior of curcumin-loaded emulsion stabilized by multi-conformation soy proteins: Influence of oil volume fraction

The aim of this work was to assess the potential of nanoemulsions stabilized by mixed soy protein with multi-conformation as curcumin carrier, and the influence of oil volume fraction on stability and gastrointestinal behavior of curcumin-loaded emulsion was investigated. Loading efficiency showed a slight increase with higher oil content, though the difference was not statistically significant. With the increase of oil, the viscosity (Pa‧s), thixotropy (area of hysteresis loop) and particle size of the emulsion increased, which facilitated the physical and chemical stability of curcumin-loaded emulsion. However, the free fatty acid release rate and bioaccessibility of curcumin was negatively correlated with the oil volume fraction and the particle size of emulsion after gastric digestion. Notably, the digestion in stomach did not affect the structure of interfacial protein, demonstrating that protein-based nanoemulsions exhibited resistance to gastric digestion. This study provides theoretical guidance for the application of protein-based emulsion in curcumin delivery.

Enhancing Curcumin's therapeutic potential in cancer treatment through ultrasound mediated liposomal delivery

Improving the efficacy of chemotherapy remains a key challenge in cancer treatment, considering the low bioavailability, high cytotoxicity, and undesirable side effects of some clinical drugs. Targeted delivery and sustained release of therapeutic drugs to cancer cells can reduce the whole-body cytotoxicity of the agent and deliver a safe localized treatment to the patient. There is growing interest in herbal drugs, such as curcumin, which is highly noted as a promising anti-tumor drug, considering its wide range of bioactivities and therapeutic properties against various tumors. Conversely, the clinical efficacy of curcumin is limited because of poor oral bioavailability, low water solubility, instability in gastrointestinal fluids, and unsuitable pH stability. Drug-delivery colloid vehicles like liposomes and nanoparticles combined with microbubbles and ultrasound-mediated sustained release are currently being explored as effective delivery modes in such cases. This study aimed to synthesize and study the properties of curcumin liposomes (CLs) and optimize the high-frequency ultrasound release and uptake by a human breast cancer cell line (HCC 1954) through in vitro studies of culture viability and cytotoxicity. CLs were effectively prepared with particles sized at 81 ± 2 nm, demonstrating stability and controlled release of curcumin under ultrasound exposure. In vitro studies using HCC1954 cells, the combination of CLs, ultrasound, and Definity microbubbles significantly improved curcumin's anti-tumor effects, particularly under specific conditions: 15 s of continuous ultrasound at 0.12 W/cm2 power density with 0.6 × 107 microbubbles/mL. Furthermore, the study delved into curcumin liposomes' cytotoxic effects using an Annexin V/PI-based apoptosis assay. The treatment with CLs, particularly in conjunction with ultrasound and microbubbles, amplified cell apoptosis, mainly in the late apoptosis stage, which was attributed to heightened cellular uptake within cancer cells.

Oil-Based Curcuminoid Phospholipid Formulation Mimicking Natural Digestion Enhances Oral Bioavailability of Curcuminoids in Healthy Subjects

Curcumin, the fat-soluble active ingredient and major compound of curcuminoids contained in the curcuma root, is known for its physiological low absorption and bioavailability. Various formulations and galenic technologies are currently available on the market. In this study, the product tested was provided as a soft gelatin capsule containing curcuminoids in an oily matrix mixed with phospholipids (oil/phospholipids [PL]-based, no new technologies applied or artificial excipients added). This was intended to improve bioavailability of curcuminoids as well as to mimic the natural digestion process of fat-soluble substances. In particular, the oral bioavailability of curcuminoids in the oil/PL-based formulation was compared with the pure curcuminoids extract alone (reference product), in a randomized, cross-over, single oral dose study design. Twelve healthy subjects were administered 200 mg curcuminoids under fasting conditions. Pharmacokinetic parameters were analyzed from individual concentration-time curves of total curcuminoids, as well as the curcumin metabolite tetrahydrocurcumin (THC). Results showed significantly higher AUC0-8h levels after the intake of the oil/PL-based formulation for total curcuminoids (205.60 vs. 112.50 ng/mL*h, P = .0001) as well as for THC (347.30 vs. 118.90 ng/mL*h, P < .0001) in comparison to the pure curcuminoids extract. Cmax was also significantly higher for both parameters analyzed (total curcuminoids: 47.54 vs. 21.16 ng/mL, P = .0001; THC: 96.69 vs. 29.83 ng/mL, P < .0001). In addition, the uptake kinetic of total curcuminoids was significantly fastened with the oil/PL-based curcuminoids formulation compared with the pure curcuminoids extract (P = .0446). These data suggest an improved impact on curcuminoids uptake of the oil/PL-based formulation and confirms its good tolerability.

Curcumin as a Multifunctional Spice Ingredient against Mental Disorders in Humans: Current Clinical Studies and Bioavailability Concerns

BACKGROUND

Mental disorders in terms of depression, anxiety, and stress are one of the major causes of burden globally. Over the last two decades, the use of plant-based substances in the treatment of mental disorders in combination or not with medication has increasingly attracted the interest of the scientific research community. However, even if there is a plethora of naturally occurring bioactive compounds, most of them have low bioavailability, rendering them unable to insert into the bloodstream to exert their biological activities.

METHODS

This is a comprehensive narrative review that critically summarizes and scrutinizes the new approaches to the treatment of mental disorders using curcumin, also highlighting its bioavailability properties. The most accurate were searched using effective and relevant keywords.

RESULTS

This narrative review reveals substantial evidence that curcumin can exert significant effects on several mental disorders. However, despite the low cost, the extensive and confirmed potency of curcumin and its involvement in signaling pathways and the scientifically confirmed data regarding its molecular mechanisms of action against mental disorders, this naturally occurring compound presents low oral bioavailability. Pharmaceutical technology has provided solutions to increase the bioavailability of curcumin. Combination with piperine, galactomannosides, liposomal formulation or nanoformulation overcomes the bioavailability and solubility disadvantages.

CONCLUSIONS

Although curcumin demonstrates anti-anxiety, anti-depressive and anti-stress properties, studies on humans are limited and heterogeneous. Further research is highly recommended to determine the most functional formula, dose, duration, and possible side effects of curcumin on mental disorders in humans. Based on the current knowledge, the curcumin nanoformulation and Theracurmin, a form of colloidal submicroscopic particles, seem to be the most effective bioavailable formulations, which may be examined in future clinical human studies.

pH-responsive niosome-based nanocarriers of antineoplastic agents

Differences in pH between the tumour interstitium and healthy tissues can be used to induce conformational changes in the nanocarrier structure, thereby triggering drug release at the desired site. In the present study, novel pH-responsive nanocarriers were developed by modifying conventional niosomes with hexadecyl-poly(acrylic acid)n copolymers (HD-PAAn). Niosomal vesicles were prepared by the thin film hydration method using Span 60, Span 60/Tween 60 and cholesterol as main constituents, and HD-PAA modifiers of different concentrations (0.5, 1, 2.5, 5 mol%). Next, two model substances, a water-soluble fluorescent dye (calcein) and a hydrophobic agent with pronounced antineoplastic activity (curcumin), were loaded in the aqueous core and hydrophobic membrane of the elaborated niosomes, respectively. Physicochemical properties of blank and loaded nanocarriers such as hydrodynamic diameter (Dh), size distribution, zeta potential, morphology and pH-responsiveness were investigated in detail. The cytotoxicity of niosomal curcumin was evaluated against human malignant cell lines of different origins (MJ, T-24, HUT-78), and the mechanistic aspects of proapoptotic effects were elucidated. The formulation composed of Span 60/Tween 60/cholesterol/2.5% HD-PAA17 exhibited optimal physicochemical characteristics (Dh 302 nm; ζ potential -22.1 mV; high curcumin entrapment 83%), pH-dependent drug release and improved cytotoxic and apoptogenic activity compared to free curcumin.

Collision of herbal medicine and nanotechnology: a bibliometric analysis of herbal nanoparticles from 2004 to 2023

BACKGROUND

Herbal nanoparticles are made from natural herbs/medicinal plants, their extracts, or a combination with other nanoparticle carriers. Compared to traditional herbs, herbal nanoparticles lead to improved bioavailability, enhanced stability, and reduced toxicity. Previous research indicates that herbal medicine nanomaterials are rapidly advancing and making significant progress; however, bibliometric analysis and knowledge mapping for herbal nanoparticles are currently lacking. We performed a bibliometric analysis by retrieving publications related to herbal nanoparticles from the Web of Science Core Collection (WoSCC) database spanning from 2004 to 2023. Data processing was performed using the R package Bibliometrix, VOSviewers, and CiteSpace.

RESULTS

In total, 1876 articles related to herbal nanoparticles were identified, originating from various countries, with China being the primary contributing country. The number of publications in this field increases annually. Beijing University of Chinese Medicine, Shanghai University of Traditional Chinese Medicine, and Saveetha University in India are prominent research institutions in this domain. The Journal "International Journal of Nanomedicine" has the highest number of publications. The number of authors of these publications reached 8234, with Yan Zhao, Yue Zhang, and Huihua Qu being the most prolific authors and Yan Zhao being the most frequently cited author. "Traditional Chinese medicine," "drug delivery," and "green synthesis" are the main research focal points. Themes such as "green synthesis," "curcumin," "wound healing," "drug delivery," and "carbon dots" may represent emerging research areas.

CONCLUSIONS

Our study findings assist in identifying the latest research frontiers and hot topics, providing valuable references for scholars investigating the role of nanotechnology in herbal medicine.

The effect of curcumin supplementation on circulating adiponectin and leptin concentration in adults: a GRADE-assessed systematic review and meta-analysis of randomised controlled trials

Curcumin is a phytocompound found in the root of turmeric, a common herbal ingredient in many Asian cuisines. The compound contains anti-inflammatory activity, which is mediated through an upregulation of adiponectin and reduction of leptin. Results of randomised controlled trials (RCT) have shown that the effects of curcumin on adipokines are conflicting. Therefore, the current systematic review and meta-analysis of RCT were conducted with the aim of elucidating the role of curcumin supplementation on serum adiponectin and leptin. The search included PubMed, Embase, Cochrane Library, Scopus, Web of Science and Google Scholar from inception to August 2023. For net changes in adipokines, standardised mean differences (SMD) were calculated using random effects models. Thirteen RCT with fourteen treatment arms were eligible for inclusion in this meta-analysis. Curcumin supplementation was effective in increasing serum adiponectin (SMD = 0·86, 95 % CI (0·33, 1·39), P < 0·001; I2 = 93·1 %, P < 0·001) and reducing serum leptin (SMD = -1·42, 95 % CI (-2·29, -0·54), P < 0·001; I2 = 94·7 %, P < 0·001). In conclusion, curcumin supplementation significantly increased circulating adiponectin and decreased leptin levels in adults.

Cyclocurcumin as Promising Bioactive Natural Compound: An Overview

Although identical in molecular formula and weight, curcumin and cyclocurcumin show remarkable differences in their reactivity. Both are natural compounds isolated from the rhizome of turmeric, the former is involved in the diketo/keto-enol tautomerism through the bis-α,β-unsaturated diketone unit according to the polarity of the solvent, while the latter could react by trans-cis isomerization due to the presence of the α,β-unsaturated dihydropyranone moiety. Even if curcumin is generally considered responsible of the therapeutical properties of Curcuma longa L. due to its high content, cyclocurcumin has attracted great interest over the last several decades for its individual behavior and specific features as a bioactive compound. Cyclocurcumin has a hydrophobic nature characterized by fluorescence emission, solvatochromism, and the tendency to form spherical fluorescent aggregates in aqueous solution. Molecular docking analysis reveals the potentiality of cyclocurcumin as antioxidant, enzyme inhibitor, and antiviral agent. Promising biological activities are observed especially in the treatment of degenerative and cardiovascular diseases. Despite the versatility emerging from the data reported herein, the use of cyclocurcumin seems to remain limited in clinical applications mainly because of its low solubility and bioavailability.

Preparation and characterization of fine and stable short amylose nanocarriers for curcumin using a highly efficient and convenient method

To prepare fine and stable nanocarriers for curcumin using a highly efficient and convenient method, nanoprecipitation combined with ultrasonication and a high-speed dispersion (US+HSS) method were used to prepare short amylose nanoparticles with pre-formed helical structures. Their morphology, structural characteristics, and embedding effects for curcumin were investigated. The results showed that the optimal ratio of ethanol to short amylose solution and ultrasonic time was 4:1 and 4 min, respectively. The nanoparticles showed a small size (82.43 nm), relatively high loading capacity (11.57 %), and a peak gelatinization temperature of 97.74 °C. Compared to the nanoprecipitation method, the short amylose nanoparticles prepared using the US+HSS method possessed a higher V-type crystalline structure ratio. In addition, the US+HSS method was easier to use to prepare nanoparticles with high stability against NaCl, and the stable nanoparticles showed the best in vitro sustained release effect for curcumin. The Peppas-Sahlin model was the optimal model that matched curcumin release from nanoparticles during digestion.

Cytotoxicity Enhancement in Osteosarcoma with Multifunctional I-131 Radiotherapeutic Nanoparticles: In Vitro Three-Dimensional Spheroid Model and Release Kinetics Modeling

This novel radiolabeled chitosan nanoparticle, facilitated with curcumin, increased doxorubicin cytotoxicity and radiosensitivity to MG-63 osteosarcoma cells in a three-dimensional model. Delivery of the anti-epidermal growth factor receptor (EGFR) targeted carboxymethyl chitosan nanoparticles, directly labeled with Na131I (ICED-N), achieved deep tumor penetration in a three-dimensional model. Of three kinetic models, the Higuchi model more closely matched the experimental curve and release profiles. The anti-EGFR targeting resulted in a 513-fold greater targeting efficacy to MG-63 (EGFR+) cells than the control fibroblast (EGFR-) cells. The curcumin-enhanced ICED-N (4 × 0.925 MBq) fractionated-dose regime achieved an 18.3-fold increase in cell cytotoxicity compared to the single-dose (1 × 3.70 MBq) doxorubicin-loaded nanoparticle, and a 13.6-fold increase in cell cytotoxicity compared to the single-dose Na131I nanoparticle. Moreover, the ICED-N fractionated dose increased cells in the G2/M phase 8.78-fold, indicating the cell cycle arrest in the G2/M phase is associated with DNA fragmentation, and the intracellular damage is unable to be repaired. Overall, the results indicate that the fractionated dose was more efficacious than a single dose, and curcumin substantially increased doxorubicin cytotoxicity and amplified osteosarcoma cell radiosensitivity to Na131I.

Bioavailability of Oral Curcumin in Systematic Reviews: A Methodological Study

Curcumin is a natural compound found in turmeric that exhibits diverse biological activities. However, its poor bioavailability limits its therapeutic application, which has led to the development of various bioavailability-improved formulations. In this methodological study, we analyzed whether systematic reviews on curcumin considered the bioavailability of systemic oral curcumin formulations when synthesizing evidence from human clinical trials. A total of 171 systematic reviews published between 2003 and 2022 were included in the study. From the included studies, we extracted data on study characteristics; type of curcumin; methods; and reporting regarding bioavailability, funding, and conflict of interest. Our results show that systematic reviews rarely consider the variable bioavailability of tested curcumin formulations. Relevant statistical subgroup and/or sensitivity analyses were reported in the methods and results of only 3.5% and 6.4% of reviews, respectively. However, more reviews mentioned bioavailability in their discussion (57%) or conclusion (13%). The detailed analysis of the included systematic reviews suggests that there is broad recognition of product bioavailability as a crucial factor affecting the health effects of curcumin, which is not accompanied by adequate evidence synthesis. Therefore, the results of most systematic reviews on orally administered curcumin should be taken with caution.

Biopolymeric nanofibrous scaffolds of poly(3-hydroxybuthyrate)/chitosan loaded with biogenic silver nanoparticle synthesized using curcumin and their antibacterial activities

The increasing prevalence of multi-drug resistant bacteria poses a significant threat to public health, especially in wound infections. Developing new bactericidal agents and treatment strategies is crucial to address this issue. In this study, biopolymeric nanofibrous scaffolds containing green-synthesized silver nanoparticles (AgNPs) with curcumin (CUR) were evaluated as antimicrobial materials for wound healing therapy. Firstly, CUR was utilized to synthesize AgNPs, which were then analyzed using various analytical methods. The microstructural analysis revealed that the biogenic AgNPs, which had a spherical shape and an average size of 19.83 nm, were uniformly anchored on PHB/CTS nanofibers. Then, the AgNPs with various content (0.25-1%wt) were incorporated into PHB/CTS matrix to enhance its wettability, thermal and bactericidal behaviors. The nanofibrous scaffolds were characterized by FT-IR, FE-SEM, TGA analysis and water contact angle measurement. Overall, the addition of CUR-AgNPs to the PHB/CTS matrix led to a reduction in fiber diameter, enhanced hydrophilicity and improved thermal properties. Additionally, antibacterial activity against Staphylococcus aureus and Escherichia coli was performed on samples of AgNPS and PHB/CTS/CUR-Ag. The synthesized AgNPs showed antibacterial activity against both microorganisms, especially against S. aureus. Higher concentrations of AgNPs in nanofibers led to a significant reduction in bacterial colony formation. The results displayed that PHB/CTS/CUR-AgNPs nanofibrous scaffolds could be a promising material for the biomedical applications such as wound healing.

Molecular Mechanisms of Curcumin in the Pathogenesis of Metabolic Dysfunction Associated Steatotic Liver Disease

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a multifactorial condition characterized by insulin resistance, oxidative stress, chronic low-grade inflammation, and sometimes fibrosis. To date, no effective pharmacological therapy has been approved for the treatment of metabolic-associated steatohepatitis (MASH), the progressive form of MASLD. Recently, numerous in vitro and in vivo studies have described the efficacy of nutraceutical compounds in the diet has been tested. Among them, curcumin is the most widely used polyphenol in the diet showing potent anti-inflammatory and antifibrotic activities. This review aims to summarize the most important basic studies (in vitro and animal models studies), describing the molecular mechanisms by which curcumin acts in the context of MASLD, providing the rationale for its effective translational use in humans.

Advanced application of nanotechnology in active constituents of Traditional Chinese Medicines

Traditional Chinese Medicines (TCMs) have been used for centuries for the treatment and management of various diseases. However, their effective delivery to targeted sites may be a major challenge due to their poor water solubility, low bioavailability, and potential toxicity. Nanocarriers, such as liposomes, polymeric nanoparticles, inorganic nanoparticles and organic/inorganic nanohybrids based on active constituents from TCMs have been extensively studied as a promising strategy to improve the delivery of active constituents from TCMs to achieve a higher therapeutic effect with fewer side effects compared to conventional formulations. This review summarizes the recent advances in nanocarrier-based delivery systems for various types of active constituents of TCMs, including terpenoids, polyphenols, alkaloids, flavonoids, and quinones, from different natural sources. This review covers the design and preparation of nanocarriers, their characterization, and in vitro/vivo evaluations. Additionally, this review highlights the challenges and opportunities in the field and suggests future directions for research. Nanocarrier-based delivery systems have shown great potential in improving the therapeutic efficacy of TCMs, and this review may serve as a comprehensive resource to researchers in this field.

ERK/NF-kB/COX-2 Signaling Pathway Plays a Key Role in Curcumin Protection against Acetaminophen-Induced Liver Injury

Recent experimental studies have highlighted the beneficial effects of curcumin on liver injury induced by acetaminophen (APAP). However, the specific molecular mechanisms underlying curcumin's hepatoprotective effects against APAP-induced liver injury remain to be fully elucidated. This study aimed to investigate the therapeutic effect of curcumin on APAP-induced liver injury using a mouse model. In the experiment, mice were subjected to an intraperitoneal hepatotoxic dose of APAP (300 mg/kg) to induce hepatotoxicity. After 30 min of APAP administration, the mice were treated with different concentrations of curcumin (0, 10, 25, or 50 mg/kg). After 16 h, mice with hepatotoxicity showed elevated levels of serum alanine transaminase (ALT), aspartate transaminase (AST), hepatic myeloperoxidase (MPO), TNF-α, and IL-6, and decreased levels of glutathione (GSH). Moreover, there was an increased infiltration of neutrophils and macrophages following intraperitoneal injection of APAP. However, curcumin-treated mice displayed a pronounced reduction in serum ALT, AST, hepatic MPO, TNF-α, and IL-6 levels, coupled with a notable elevation in GSH levels compared to the APAP-treated hepatotoxic mice. Moreover, curcumin treatment led to reduced infiltration of neutrophils and macrophages. Additionally, curcumin inhibited the phosphorylation of ERK and NF-kB proteins while reducing the expression of cyclooxygenase-2 (COX-2). These findings highlight the hepatoprotective potential of curcumin against APAP-induced liver injury through the suppression of the ERK, NF-kB, and COX-2 signaling pathways.

Novel Biphasic In Vitro Dissolution Method Correctly Predicts the Oral Bioavailability of Curcumin in Humans

In vitro dissolution methods correctly predicting in vivo bioavailability of compounds from complex mixtures are lacking. We therefore used data on the in vivo performance of bioavailability-improved curcumin formulations to implement an in vivo predictive dissolution method (BiPHa+). BiPHa+ was applied for the characterization of eight curcumin formulations previously studied in a strictly controlled pharmacokinetic human trial. During dissolution, the dissolved proportion of curcumin in the aqueous medium underwent a formulation-dependent reduction, whereas the proportion remained stable in the organic layer. Compared with conventional dissolution systems, BiPHa+ was superior in terms of in vivo-relevant formulation characterization. All formulations could be precisely categorized according to their bioavailability in humans. In vitro-in vivo relationships for each dissolution method were established, with BiPHa+ providing the highest degree of linearity (r2 = 0.9975). The BiPHa+ assay correctly predicted the bioavailability of curcuminoids from complex mixtures and provided mechanistic information about formulation-dependent release characteristics.

Preparation of Self-Assembled, Curcumin-Loaded Nano-Micelles Using Quarternized Chitosan-Vanillin Imine (QCS-Vani Imine) Conjugate and Evaluation of Synergistic Anticancer Effect with Cisplatin

Nano-micelles are self-assembling colloidal dispersions applied to enhance the anticancer efficacy of chemotherapeutic agents. In this study, the conjugate of quarternized chitosan and vanillin imine (QCS-Vani imine) was synthesized using the reaction of a Schiff base characterized by proton-NMR (1HNMR), UV-Vis spectroscopy, and FT-IR. The critical micelle concentration (CMC), particle size, and zeta potential of the resulting product were determined. The QCS-Vani imine conjugate was used as a carrier for the development of curcumin-loaded nano-micelles, and their entrapment efficiency (%EE), drug-loading capacity (%LC) and in vitro release were investigated using HPLC analysis. Moreover, the nano-micelles containing curcumin were combined with various concentrations of cisplatin and evaluated for a possible anticancer synergistic effect. The anticancer activity was evaluated against lung cancer A549 and mouse fibroblast L929 cell lines. The percent yield (%) of the QCS-Vani imine conjugate was 93.18%. The curcumin-loaded QCS-Vani imine nano-micelles were characterized and found to have a spherical shape (by TEM) with size < 200 nm (by DLS) with high %EE up to 67.61% and %LC up to 6.15 ± 0.41%. The loaded lyophilized powder of the nano-micelles was more stable at 4 °C than at room temperature during 120 days of storage. pH-sensitive release properties were observed to have a higher curcumin release at pH 5.5 (cancer environment) than at pH 7.4 (systemic environment). Curcumin-loaded QCS-Vani imine nano-micelles showed higher cytotoxicity and selectivity toward lung cancer A549 cell lines and exhibited lower toxicity toward the normal cell (H9C2) than pure curcumin. Moreover, the curcumin-loaded QCS-Vani imine nano-micelles exhibited an enhanced property of inducing cell cycle arrest during the S-phase against A549 cells and showed prominently induced apoptosis in lung cancer cells compared to that with curcumin. The co-treatment of cisplatin with curcumin-loaded QCS-Vani imine nano-micelles presented an enhanced anticancer effect, showing 8.66 ± 0.88 μM as the IC50 value, in comparison to the treatment with cisplatin alone (14.22 ± 1.01 μM). These findings suggest that the developed QCS-Vani imine nano-micelle is a potential drug delivery system and could be a promising approach for treating lung cancer in combination with cisplatin.

The Anti-Oxidant Curcumin Solubilized as Oil-in-Water Nanoemulsions or Chitosan Nanocapsules Effectively Reduces Helicobacter pylori Growth, Bacterial Biofilm Formation, Gastric Cell Adhesion and Internalization

The bacterium Helicobacter pylori (H. pylori) represents a major risk factor associated with the development of gastric cancer. The anti-oxidant curcumin has been ascribed many benefits to human health, including bactericidal effects. However, these effects are poorly reproducible because the molecule is extremely unstable and water insoluble. Here we solubilized curcumin as either nanoemulsions or chitosan nanocapsules and tested the effects on H. pylori. The nanoemulsions were on average 200 nm in diameter with a PdI ≤ 0.16 and a negative zeta potential (-54 mV), while the nanocapsules were 305 nm in diameter with a PdI ≤ 0.29 and a positive zeta potential (+68 mV). Nanocapsules were safer than nanoemulsions when testing effects on the viability of GES-1 gastric cells. Also, nanocapsules were more efficient than nanoemulsions at inhibiting H. pylori growth (minimal inhibitory concentration: 50 and 75 μM, respectively), whereby chitosan contributed to this activity. Importantly, both formulations effectively diminished H. pylori's adherence to and internalization by GES-1 cells, as well as biofilm formation. In summary, the demonstrated activity of the curcumin nanoformulations described here against H. pylori posit them as having great potential to treat or complement other therapies currently in use against H. pylori infection.

Curcumin Nanoemulsion: Unveiling Cardioprotective Effects via ACE Inhibition and Antioxidant Properties in Hypertensive Rats

Background and Objectives: Curcumin, derived from Curcuma longa, is a well-known traditional medicinal compound recognized for its therapeutic attributes. Nevertheless, its efficacy is hampered by limited bioavailability, prompting researchers to explore the application of nanoemulsion as a potential alternative. Materials and Methods: This study delves into the antihypertensive effects of curcumin nanoemulsion (SNEC) by targeting the renin-angiotensin-aldosterone system (RAAS) and oxidative stress in deoxycorticosterone acetate (DOCA) salt-induced hypertensive rats. To gauge the cardio-protective impact of SNEC in DOCA salt-induced hypertension, molecular docking was undertaken, uncovering curcumin's high affinity and adept binding capabilities to the active site of angiotensin-converting enzyme (ACE). Additionally, the investigation employed uninephrectomized rats to assess hemodynamic parameters via an AD instrument. Serum ACE, angiotensin II, blood urea nitrogen (BUN), and creatinine levels were quantified using ELISA kits, while antioxidant parameters were evaluated through chemical assays. Result: The outcomes of the molecular docking analysis revealed robust binding of curcumin to the ACE active site. Furthermore, oral administration of SNEC significantly mitigated systolic, diastolic, and mean arterial blood pressure in contrast to the DOCA-induced hypertensive group. SNEC administration also led to a reduction in left ventricular end-diastolic pressure (LVEDP) and an elevation in the maximum rate of left ventricular pressure rise (LV (dP/dt) max). Moreover, SNEC administration distinctly lowered serum levels of ACE and angiotensin II compared to the hypertensive DOCA group. Renal markers, including serum creatinine and BUN, displayed a shift toward normalized levels with SNEC treatment. Additionally, SNEC showcased potent antioxidant characteristics by elevating reduced glutathione, catalase, and superoxide dismutase levels, while decreasing the concentration of thiobarbituric acid reactive substances. Conclusions: Collectively, these findings underscore that curcumin nanoemulsion exerts noteworthy cardio-protective effects through ACE activity inhibition and remarkable antioxidant properties.

γ-Cyclodextrin Metal-Organic Frameworks: Do Solvents Make a Difference?

Conventionally, methanol is the solvent of choice in the synthesis of gamma-cyclodextrin metal-organic frameworks (γ-CD-MOFs), but using ethanol as a replacement could allow for a more food-grade synthesis condition. Therefore, the aim of the study was to compare the γ-CD-MOFs synthesised with both methanol and ethanol. The γ-CD-MOFs were characterised by scanning electron microscopy (SEM), surface area and pore measurement, Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction (PXRD). The encapsulation efficiency (EE) and loading capacity (LC) of the γ-CD-MOFs were also determined for curcumin, using methanol, ethanol and a mixture of the two as encapsulation solvent. It was found that γ-CD-MOFs synthesised by methanol and ethanol do not differ greatly, the most significant difference being the larger crystal size of γ-CD-MOFs crystallised from ethanol. However, the change in solvent significantly influenced the EE and LC of the crystals. The higher solubility of curcumin in ethanol reduced interactions with the γ-CD-MOFs and resulted in lowered EE and LC. This suggests that different solvents should be used to deliberately manipulate the EE and LC of target compounds for better use of γ-CD-MOFs as their encapsulating and delivery agents.

Curcumin-Loaded Bamboo Shoot Cellulose Nanofibers: Characterization and In Vitro Studies

Given its high biological and pharmacological activities, curcumin (CUR) offers promising applications in functional foods. However, its low stability and bioavailability have greatly hindered its application in the food industry. The present study prepared cellulose nanofiber (CNF) from bamboo shoot processing byproducts and investigated its potential as a low-cost carrier. Our results showed that CUR was immobilized on CNF surfaces mainly through hydrogen bonding and eventually encapsulated in CNF matrices, forming a CNF-CUR complex with an encapsulation efficiency of 88.34% and a loading capacity of 67.95%. The CUR encapsulated in the complex showed improved stability after thermal and UV light treatments. Moreover, a slow and extended release pattern of CUR in a simulated gastrointestinal tract was observed, which could be appropriately described using the Korsmeyer-Peppas model. These results revealed that CNF is a promising protective carrier for the slow release of CUR, making it a better candidate for functional foods.

Protective effects of curcumin against osteoporosis and its molecular mechanisms: a recent review in preclinical trials

Osteoporosis (OP) is one of the most common metabolic skeletal disorders and is commonly seen in the elderly population and postmenopausal women. It is mainly associated with progressive loss of bone mineral density, persistent deterioration of bone microarchitecture, and increased fracture risk. To date, drug therapy is the primary method used to prevent and treat osteoporosis. However, long-term drug therapy inevitably leads to drug resistance and specific side effects. Therefore, researchers are constantly searching for new monomer compounds from natural plants. As a candidate for the treatment of osteoporosis, curcumin (CUR) is a natural phenolic compound with various pharmacological and biological activities, including antioxidant, anti-apoptotic, and anti-inflammatory. This compound has gained research attention for maintaining bone health in various osteoporosis models. We reviewed preclinical and clinical studies of curcumin in preventing and alleviating osteoporosis. These results suggest that if subjected to rigorous pharmacological and clinical trials, naturally-derived curcumin could be used as a complementary and alternative medicine for the treatment of osteoporosis by targeting osteoporosis-related mechanistic pathways. This review summarizes the mechanisms of action and potential therapeutic applications of curcumin in the prevention and mitigation of osteoporosis and provides reference for further research and development of curcumin.

The bioavailability, metabolism and microbial modulation of curcumin-loaded nanodelivery systems

Curcumin (Cur), the major bioactive component of turmeric (Curcuma longa) possesses many health benefits. However, low solubility, stability and bioavailability restricts its applications in food. Recently, nanocarriers such as complex coacervates, nanocapsules, liposomes, nanoparticles, nanomicelles, have been used as novel strategies to solve these problems. In this review, we have focused on the delivery systems responsive to the environmental stimuli such as pH-responsive, enzyme-responsive, targeted-to-specific cells or tissues, mucus-penetrating and mucoadhesive carriers. Besides, the metabolites and their biodistribution of Cur and Cur delivery systems are discussed. Most importantly, the interaction between Cur and their carriers with gut microbiota and their effects of modulating the gut health synergistically were discussed comprehensively. In the end, the biocompatibility of Cur delivery systems and the feasibility of their application in food industry is discussed. This review provided a comprehensive review of Cur nanodelivery systems, the health impacts of Cur nanocarriers and an insight into the application of Cur nanocarriers in food industry.

On the photobehaviour of curcumin in biocompatible hosts: The role of H-abstraction in the photodegradation and photosensitization

Curcumin (CUR) is a naturally occurring pigment extensively studied due to its therapeutic activity and delivered by suitable nanocarriers to overcome poor solubility in aqueous media. The significant absorption of CUR in the visible blue region has prompted its use as a potential phototherapeutic agent in treating infectious and cancer diseases, although the mechanism underlying the phototoxic effects is still not fully understood. This contribution investigates the photobehaviour of CUR within polymeric micelles, microemulsions, and zein nanoparticles, chosen as biocompatible nanocarriers, and human serum albumin as a representative biomolecule. Spectroscopic studies indicate that in all host systems, the enolic tautomeric form of CUR is converted in a significant amount of the diketo form because of the perturbation of the intramolecular hydrogen bond. This leads to intermolecular H-abstraction from the host components by the lowest excited triplet state of CUR with the formation of the corresponding ketyl radical, detected by nanosecond laser flash photolysis. This radical is oxidized by molecular oxygen, likely generating peroxyl and hydroperoxyl radical species, unless in Zein, reasonably due to the poor availability of oxygen in the closely packed structure of this nanocarrier. In contrast, no detectable formation of singlet oxygen was revealed in all the systems. Overall these results highlight the key role of the H-abstraction process over singlet oxygen sensitization as a primary photochemical pathway strictly dictated by the specific features of the microenvironment, providing new insights into the photoreactivity of CUR in biocompatible hosts that can also be useful for a better understanding of its phototoxicity mechanism.

Co-Encapsulation of Curcumin and α-Tocopherol in Bicosome Systems: Physicochemical Properties and Biological Activity

A novel co-encapsulation system called bicosomes (bicelles within liposomes) has been developed to overcome the limitations associated with the topical application of curcumin (cur) and α-tocopherol (α-toc). The physicochemical properties and biological activity in vitro of bicosome systems were evaluated. Bicelles were prepared with DPPC, DHPC, cur, and α-toc (cur/α-toc-bicelles). Liposomal vesicles loading cur/α-toc-bicelles were prepared with Lipoid P-100 and cholesterol-forming cur/α-toc-bicosomes. Three cur/α-toc-bicosomes were evaluated using different total lipid percentages (12, 16, and 20% w/v). The results indicated that formulations manage to solubilize cur and α-toc in homogeneous bicelles < 20 nm, while the bicosomes reaches 303-420 nm depending on the total lipid percentage in the systems. Bicosomes demonstrated high-encapsulation efficiency (EE) for cur (56-77%) and α-toc (51-65%). The loading capacity (LC) for both antioxidant compounds was 52-67%. In addition, cur/α-toc-bicosomes decreased the lipid oxidation by 52% and increased the antioxidant activity by 60% compared to unloaded bicosomes. The cell viability of these cur/α-toc-bicosomes was >85% in fibroblasts (3T3L1/CL-173™) and ≥65% in keratinocytes (Ha-CaT) and proved to be hematologically compatible. The cur/α-toc-bicelles and cur/α-toc-bicosomes inhibited the growth of C. albicans in a range between 33 and 76%. Our results propose bicosome systems as a novel carrier able to co-encapsulate, solubilize, protect, and improve the delivery performance of antioxidant molecules. The relevance of these findings is based on the synergistic antioxidant effect of its components, its biocompatibility, and its efficacy for dermal tissue treatment damaged by oxidative stress or by the presence of C. albicans. However, further studies are needed to assess the efficacy and safety of cur/α-toc bicosomes in vitro and in vivo.

Characterization, stability and antioxidant activity of curcumin nanocomplexes with soy protein isolate and pectin

Curcumin (Cur) has antioxidant, anti-inflammatory and other biological activities, but its poor stability, low water solubility and other defects limit the application. Herein, Cur was nanocomposited with soy isolate protein (SPI) and pectin (PE) for the first time and its characterization, bioavailability and antioxidant activity were discussed. The optimal encapsulation process of SPI-Cur-PE was as follow: the addition amount of PE was 4 mg, Cur was 0.6 mg and at pH of 7. It was observed by SEM that SPI-Cur-PE were partially aggregated. The average particle size of SPI-Cur-PE was 210.1 nm and the zeta potential was -31.99 mV. Through XRD, FT-IR and DSC analysis, the SPI-Cur-PE was formed through hydrophobic interaction and electrostatic interaction. The SPI-Cur-PE released more slowly in simulated gastrointestinal treatment and displayed higher photostability and thermal stability. SPI-Cur-PE, SPI-Cur and free Cur had scavenging activities for 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radicals.

Curcumin Enhances the Anticancer Effects of Binimetinib on Melanoma Cells by Inducing Mitochondrial Dysfunction and Cell Apoptosis with Necroptosis

BACKGROUND

Recent studies suggest that MEK1/2 inhibitors, including binimetinib, significantly improve malignant melanoma (MM) patient survival. Growing evidence suggests that phytochemicals, especially curcumin, can overcome drug resistance in cancer cells through a variety of mechanisms.

OBJECTIVE

This study aims to examine curcumin's efficacy in vitro combined with binimetinib in human MM cells.

METHODS

We used 2D monolayer and 3D spheroid human epidermal melanocyte culture models, HEMn-MP (human epidermal melanocytes, neonatal, moderately pigmented), and two human MM cell lines, G361 and SK-MEL-2, to evaluate cell viability, proliferation, migration, death, and reactive oxygen species (ROS) production following single therapy treatment, with either curcumin or binimetinib, or a combination of both.

RESULTS

Compared to MM cells treated with single therapy, those with combination therapy showed significantly decreased cell viability and increased ROS production. We observed apoptosis following both single and combination therapies. However only those who had had combination therapy had necroptosis.

CONCLUSION

Collectively, our data demonstrates that curcumin exerts significant synergistic anticancer effects on MM cells by inducing ROS and necroptosis when combined with binimetinib. Therefore, a strategy of adding curcumin to conventional anticancer agents holds promise for treating MM.

Redox-Responsive Lipidic Prodrug Nano-Delivery System Improves Antitumor Effect of Curcumin Derivative C210

The poor bioavailability of curcumin and its derivatives limits their antitumor efficacy and clinical translation. Although curcumin derivative C210 has more potent antitumor activity than curcumin, it has a similar deficiency to curcumin. In order to improve its bioavailability and accordingly enhance its antitumor activity in vivo, we developed a redox-responsive lipidic prodrug nano-delivery system of C210. Briefly, we synthesized three conjugates of C210 and oleyl alcohol (OA) via different linkages containing single sulfur/disulfide/carbon bonds and prepared their nanoparticles using a nanoprecipitation method. The prodrugs required only a very small amount of DSPE-PEG2000 as a stabilizer to self-assemble in aqueous solution to form nanoparticles (NPs) with a high drug loading capacity (~50%). Among them, the prodrug (single sulfur bond) nanoparticles (C210-S-OA NPs) were the most sensitive to the intracellular redox level of cancer cells; therefore, they could rapidly release C210 in cancer cells and thus had the strongest cytotoxicity to cancer cells. Furthermore, C210-S-OA NPs exerted a dramatic improvement in its pharmacokinetic behavior; that is, the area under the curve (AUC), mean retention time and accumulation in tumor tissue were 10, 7 and 3 folds that of free C210, respectively. Thus, C210-S-OA NPs exhibited the strongest antitumor activity in vivo than C210 or other prodrug NPs in mouse models of breast cancer and liver cancer. The results demonstrated that the novel prodrug self-assembled redox-responsive nano-delivery platform was able to improve the bioavailability and antitumor activity of curcumin derivative C210, which provides a basis for further clinical applications of curcumin and its derivatives.

Curcumin as a therapeutic agent in cancer therapy: Focusing on its modulatory effects on circular RNAs

Curcumin, a natural polyphenol compound, has been identified as an effective therapeutic agent against cancer that exerts its anti-tumor activities by up/downregulating signaling mediators and modulating various cellular processes, including angiogenesis, autophagy, apoptosis, metastasis, and epithelial-mesenchymal transition (EMT). Since almost 98% of genomic transcriptional production is noncoding RNAs in humans, there is evidence that curcumin exerts therapeutic effects through the alterations of noncoding RNAs in various types of cancers. Circular RNAs (circRNAs) are formed by the back-splicing of immature mRNAs and have several functions, including functioning as miRNA sponges. It has been shown that curcumin modulated various circRNAs, including circ-HN1, circ-PRKCA, circPLEKHM3, circZNF83, circFNDC3B, circ_KIAA1199, circRUNX1, circ_0078710, and circ_0056618. The modulation of these circRNAs targeted the expression of mRNAs and modified various signaling pathways and hallmarks of cancer. In this article, we reviewed the pharmacokinetics of curcumin, its anti-cancer activities, as well as the biology and structure of circRNAs. Our main focus was on how curcumin exerts anti-cancer functions by modulating circRNAs and their target mRNAs and pathways.

Curcumin: Overview of Extraction Methods, Health Benefits, and Encapsulation and Delivery Using Microemulsions and Nanoemulsions

Curcumin is the principal curcuminoid found in the rhizomes of turmeric. Due to its therapeutic action against cancer, depression, diabetes, some bacteria, and oxidative stress, it has been used widely in medicine since ancient times. Due to its low solubility, the human organism cannot completely absorb it. Advanced extraction technologies, followed by encapsulation in microemulsion and nanoemulsion systems, are currently being used to improve bioavailability. This review discusses the different methods available for curcumin extraction from plant material, methods for the identification of curcumin in the resulting extracts, its beneficial effects on human health, and the encapsulation techniques into small colloidal systems that have been used over the past decade to deliver this compound.

The protective role of curcumin nanoparticles on the submandibular salivary gland toxicity induced by methotrexate in male rats

OBJECTIVE

To evaluate the protective role of nanocurcumin on the toxicity induced by methotrexate in the submandibular glands of rats.

DESIGN

Twenty- four healthy male Wistar albino rats were randomly distributed into 3 groups, 8 rats each. Group I-control: rats received a single intraperitoneal injection of saline; Group II-methotrexate (MTX): rats received methotrexate 20 mg/ kg day 1 of the experiment; Group III-methotrexate and nanocurcumin (MTX+NCU): rats received methotrexate 20 mg/ kg on day 1 of the experimental period in addition to nanocurcumin 100 mg/kg/day for 7 days. After euthanasia, the submandibular salivary glands of all rats were collected and prepared for histological, histomorphometric, and immunohistochemical examination (Caspase 3, Bcl2), in addition to transmission electron microscopy.

RESULTS

Histological and ultrastructural assessment revealed less salivary gland damage in the nanocurcumin group in comparison to the methotrexate group, and the percentage of acinar vacuolization showed significantly lower values in the nanocurcumin group. Group III (MTX+NCU) showed lower immunoexpression of caspase 3 than group II (MTX), while Bcl2 immunoreactivity was higher in the MTX group than in the MTX+NCU group.

CONCLUSIONS

Our results suggest that simultaneous administration of nanocurcumin reduces apoptosis in salivary glands subjected to methotrexate.

The Role of Thrombomodulin in Estrogen-Receptor-Positive Breast Cancer Progression, Metastasis, and Curcumin Sensitivity

Estrogen and estrogen receptors (ER) play a key role in breast cancer progression, which can be treated with endocrine therapy. Nevertheless, resistance to endocrine therapies is developed over time. The tumor expression of thrombomodulin (TM) is correlated with favorable prognosis in several types of cancer. However, this correlation has not yet been confirmed in ER-positive (ER⁺) breast cancer. This study aims to evaluate the role of TM in ER⁺ breast cancer. Firstly, we found that lower TM expression correlates to poor overall survival (OS) and relapse-free survival (RFS) rates in ER⁺ breast cancer patients through Kaplan-Meier survival analysis (p < 0.05). Silencing TM in MCF7 cells (TM-KD) increased cell proliferation, migration, and invasion ability. Additionally, TM-KD MCF7 cells showed higher sensitivity (IC₅₀ 15 μM) to the anti-cancer agent curcumin than the scrambled control cells. Conversely, overexpression of TM (TM-over) in T47D cells leads to decreased cell proliferation, migration, and invasion ability. Furthermore, TM-over T47D cells showed more resistance (IC₅₀ > 40 μM) to the curcumin treatment. The PI staining, DAPI, and tunnel assay also confirmed that the curcumin-induced apoptosis in TM-KD MCF7 cells was higher (90.34%) than in the scrambled control cells (48.54%). Finally, the expressions of drug-resistant genes (ABCC1, LRP1, MRP5, and MDR1) were determined by qPCR. We found that the relative mRNA expression levels of ABCC1, LRP1, and MDR1 genes after curcumin treatment were higher in scrambled control cells than in TM-KD cells. In conclusion, our results demonstrated that TM plays a suppressive role in the progression and metastasis of ER⁺ breast cancer, and it regulates curcumin sensitivity by interfering with ABCC1, LRP1, and MDR1 gene expression.

The Role of STATs in Ovarian Cancer: Exploring Their Potential for Therapy

Ovarian cancer (OvCa) is a deadly gynecologic malignancy that presents many clinical challenges due to late-stage diagnoses and the development of acquired resistance to standard-of-care treatment protocols. There is an increasing body of evidence suggesting that STATs may play a critical role in OvCa progression, resistance, and disease recurrence, and thus we sought to compile a comprehensive review to summarize the current state of knowledge on the topic. We have examined peer reviewed literature to delineate the role of STATs in both cancer cells and cells within the tumor microenvironment. In addition to summarizing the current knowledge of STAT biology in OvCa, we have also examined the capacity of small molecule inhibitor development to target specific STATs and progress toward clinical applications. From our research, the best studied and targeted factors are STAT3 and STAT5, which has resulted in the development of several inhibitors that are under current evaluation in clinical trials. There remain gaps in understanding the role of STAT1, STAT2, STAT4, and STAT6, due to limited reports in the current literature; as such, further studies to establish their implications in OvCa are necessitated. Moreover, due to the deficiency in our understanding of these STATs, selective inhibitors also remain elusive, and therefore present opportunities for discovery.

Effects of Highly Bioavailable Curcumin Supplementation on Common Cold Symptoms and Immune and Inflammatory Functions in Healthy Japanese Subjects: A Randomized Controlled Study

This study aimed to investigate the effects of 12-week consumption of highly bioavailable curcumin (150 mg/day of Theracurmin Super [TS-P1] or Theracurmin [CR-033P]) on common cold symptoms, immune function, and inflammatory markers. A randomized, double-blind, placebo-controlled study was conducted from November 2021 to May 2022 on 99 healthy Japanese adults. Using a computerized random number generator, each subject was randomly assigned to one of the following three groups: TS-P1, CR-033P, or placebo (n = 33 per group). For 12 weeks, each group consumed the four capsules that were given to them daily. The cumulative number of days for which common cold symptoms persisted was set as the primary outcome. Immunity parameters, inflammatory parameters, liver function parameters, and physical examination results were additional outcomes. A safety assessment was also performed. Ninety-four subjects completed the study, and the per protocol set included 30 subjects in the placebo group, 32 subjects in the TS-P1 group, and 33 subjects in the CR-033P group. The cumulative number of days for which common cold symptoms persisted was significantly lower in the TS-P1 and CR-033P groups than that in the placebo group. No adverse effects were observed. Consumption of highly bioavailable curcumin, TS-P1 or CR-033P (150 mg/day), for 12 weeks reduced the number of days for which common cold symptoms persisted in healthy Japanese adults.

The effect of curcumin supplementation on weight loss and anthropometric indices: an umbrella review and updated meta-analyses of randomized controlled trials

BACKGROUND

Curcumin supplementation may promote weight loss and ameliorate obesity-related complications through its antioxidative and anti-inflammatory properties.

OBJECTIVE

An umbrella review and updated meta-analysis of randomized controlled trials (RCTs) was conducted to evaluate the effect of curcumin supplementation on anthropometric indices.

METHODS

Systematic reviews and meta-analyses (SRMAs) of RCTs were identified from electronic databases (Medline, Scopus, Cochrane, and Google Scholar) up to 31 March, 2022, without language restriction. SRMAs were included if they assessed curcumin supplementation on any of the following: BMI, body weight (BW), or waist circumference (WC). Subgroup analyses were performed, stratifying by patient types, severity of obesity, and curcumin formula. The study protocol was a priori registered.

RESULTS

From an umbrella review, 14 SRMAs with 39 individual RCTs were included with a high degree of overlap. In addition, searching was updated from the last search of included SRMAs in April 2021 up to 31 March, 2022, and we found 11 additional RCTs, bringing the total up to 50 RCTs included in the updated meta-analyses. Of these, 21 RCTs were deemed of high risk of bias. Curcumin supplementation significantly reduced BMI, BW, and WC with mean differences (MDs) of -0.24 kg/m² (95% CI: -0.32, -0.16 kg/m²), -0.59 kg (95% CI: -0.81, -0.36 kg), and -1.32 cm (95% CI: -1.95, -0.69 cm), respectively. The bioavailability-enhanced form reduced BMI, BWs, and WC more, with MDs of -0.26 kg/m² (95% CI: -0.38, -0.13 kg/m²), -0.80 kg (95% CI: -1.38, -0.23 kg) and -1.41 cm (95% CI: -2.24, -0.58 cm), respectively. Significant effects were also seen in subgroups of patients, especially in adults with obesity and diabetes.

CONCLUSIONS

Curcumin supplementation significantly reduces anthropometric indices, and bioavailability-enhanced formulas are preferred. Augmenting curcumin supplement with lifestyle modification should be an option for weight reduction. This trial was registered at PROSPERO as CRD42022321112 (https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022321112).

Nanoparticles Based on Chondroitin Sulfate from Tuna Heads and Chitooligosaccharides for Enhanced Water Solubility and Sustained Release of Curcumin

This study aimed to separate chondroitin sulfate (CS) from the heads of skipjack tuna (Katsuwonus pelamis) and yellowfin tuna (Thunnus albacares), by-products derived from canned tuna processing, via a biological process. The use of 1% w/w papain and an incubation time of 48 h resulted in a degree of hydrolysis of 93.75 ± 2.94% and a CS content of 59.53 ± 1.77 mg/100 g. The FTIR spectra of extracted CS products exhibited identical functional groups found in commercially available CS. The molecular weights of CS extracted from skipjack and yellowfin tuna heads were 11.0 kDa and 7.7 kDa, respectively. Subsequently, a CH:CS ratio of 3:2 for CS and chitooligosaccharides (CH) was chosen as the optimal ratio for the preparation of spherical nanoparticles, with %EE, mean particle size, PDI, and zeta potential values of 50.89 ± 0.66%, 128.90 ± 3.29 nm, 0.27 ± 0.04, and -12.47 ± 2.06, respectively. The CU content was enhanced to 127.21 ± 1.66 μg/mL. The release of CU from this particular nanosystem involved mainly a drug diffusion mechanism, with a burst release in the first 3 h followed by a sustained release of CU over 24 h. The DPPH and ABTS scavenging activity results confirmed the efficient encapsulation of CU into CHCS nanoparticles. This study will provide a theoretical basis for CS derived from tuna head cartilages to be used as a functional component with specific functional properties in food and biomedical applications.

Investigation of antioxidant, anti-ulcer, and analgesic potential of a metal-curcumin complex

The goal of the current study was to investigate the antioxidant, anti-ulcer, and analgesic properties of a metal-curcumin complex (MCC) utilizing different mouse and rat models. The antioxidant component of the analysis was completed in vitro, whereas the other activities were completed in vivo. The 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical cation scavenging test, the ferric-reducing antioxidant power (FRAP) assay, and the 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) free radical scavenging assay were used to measure the antioxidant activity. MCC demonstrated potent radical scavenging abilities. In all three experiments, Trolox served as the reference substance. When curcumin's radical scavenging abilities were compared, it became clear that MCC was a superior radical scavenger. Using the ethanol-induced technique on Sprague-Dawley rats, the anti-ulcerogenic effect was assessed. It shows that at an oral dosage of 100 mg/kg body weight, MCC might provide gastroprotection (b.w.). Additionally, we have examined MCC's potential as an analgesic. Swiss albino mice were used to measure the analgesic activity of MCC using the hot plate technique. At an oral dosage of 50 mg/kg b.w., MCC displayed analgesic efficacy. As a result, MCC could be useful in the management of inflammatory diseases.

Curcumin Has Beneficial Effects on Lysosomal Alpha-Galactosidase: Potential Implications for the Cure of Fabry Disease

Fabry disease is a lysosomal storage disease caused by mutations in the GLA gene that encodes alpha-galactosidase (AGAL). The disease causes abnormal globotriaosylceramide (Gb3) storage in the lysosomes. Variants responsible for the genotypic spectrum of Fabry disease include mutations that abolish enzymatic activity and those that cause protein instability. The latter can be successfully treated with small molecules that either bind and stabilize AGAL or indirectly improve its cellular activity. This paper describes the first attempt to reposition curcumin, a nutraceutical, to treat Fabry disease. We tested the efficacy of curcumin in a cell model and found an improvement in AGAL activity for 80% of the tested mutant genotypes (four out of five tested). The fold-increase was dependent on the mutant and ranged from 1.4 to 2.2. We produced evidence that supports a co-chaperone role for curcumin when administered with AGAL pharmacological chaperones (1-deoxygalactonojirimycin and galactose). The combined treatment with curcumin and either pharmacological chaperone was beneficial for four out of five tested mutants and showed fold-increases ranging from 1.1 to 2.3 for DGJ and from 1.1 to 2.8 for galactose. Finally, we tested a long-term treatment on one mutant (L300F) and detected an improvement in Gb3 clearance and lysosomal markers (LAMP-1 and GAA). Altogether, our findings confirmed the necessity of personalized therapies for Fabry patients and paved the way to further studies and trials of treatments for Fabry disease.

A novel solvent-free co-grinding preparation improves curcumin bioavailability in healthy volunteers: A single-center crossover study

Curcumin, from the rhizome of turmeric (Curcuma longa L.), has a wide variety of biological activities. Unfortunately, its poor water-solubility greatly limits its bioavailability. The purpose of this study was to evaluate CUMINUP60®, a novel preparation utilizing a solvent-free, co-grinding method designed to improve curcumin's bioavailability. We performed a single-center crossover experiment to compare the new product with standard 95% curcumin in the blood plasma of twelve healthy adults (10 males, 2 females). Total bioavailability of curcumin and its sulfate and glucuronide conjugates from the test product, measured by their areas under the curve over 12 h (AUC_0-T), showed a combined increase of 178-fold over standard curcumin and its conjugates from the reference product. The new product represents a significant improvement for providing greater bioavailability of curcumin, as compared with several other branded preparations. It therefore has broad applications for preparing curcumin as a more effective health ingredient in functional foods, beverages, and nutraceuticals.