Improved blood–brain-barrier permeability and tissue distribution following the oral administration of a food-grade formulation of curcumin with fenugreek fibre

Neuroprotective and anti-inflammatory effects of curcumin in Alzheimer's disease: Targeting neuroinflammation strategies

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by the accumulation of amyloid-beta plaques and neurofibrillary tangles, leading to neuronal loss. Curcumin, a polyphenolic compound derived from Curcuma longa, has shown potential neuroprotective effects due to its anti-inflammatory and antioxidant properties. This review aims to synthesize current preclinical data on the anti-neuroinflammatory mechanisms of curcumin in the context of AD, addressing its pharmacokinetics, bioavailability, and potential as a therapeutic adjunct. An exhaustive literature search was conducted, focusing on recent studies within the last 10 years related to curcumin's impact on neuroinflammation and its neuroprotective role in AD. The review methodology included sourcing articles from specialized databases using specific medical subject headings terms to ensure precision and relevance. Curcumin demonstrates significant neuroprotective properties by modulating neuroinflammatory pathways, scavenging reactive oxygen species, and inhibiting the production of pro-inflammatory cytokines. Despite its potential, challenges remain regarding its limited bioavailability and the scarcity of comprehensive human clinical trials. Curcumin emerges as a promising therapeutic adjunct in AD due to its multimodal neuroprotective benefits. However, further research is required to overcome challenges related to bioavailability and to establish effective dosing regimens in human subjects. Developing novel delivery systems and formulations may enhance curcumin's therapeutic potential in AD treatment.

Review: bioavailability and efficacy of 'free' curcuminoids from curcumagalactomannoside (CGM) curcumin formulation

The golden spice turmeric with its main bioactive component curcumin is one of the most popular and extensively studied nutraceuticals. Despite numerous pre-clinical studies reporting positive pharmacodynamics of turmeric extracts and curcumin, the main issues in translating the pharmacological effects to clinical efficacy have been to overcome its poor pharmacokinetics and to deliver significant amounts of the biologically relevant forms of the actives to various tissues. This review is aimed at providing a first critical evaluation of the current published literature with the novel curcumagalactomannoside (CGM) formulation of curcumin using fenugreek galactomannan dietary fibre, specifically designed to address curcumin poor pharmacokinetics. We describe CGM and its technology as a food-grade formulation to deliver 'free' unconjugated curcuminoids with enhanced bioavailability and improved pharmacokinetic properties. The therapeutic relevance of improving bioavailability of 'free' curcuminoids and some of the technical challenges in the measurement of the 'free' form of curcuminoids in plasma and tissues are also discussed. A total of twenty-six manuscripts are reviewed here, including fourteen pre-clinical and twelve clinical studies that have investigated CGM pharmacokinetics, safety and efficacy in various animal models and human conditions. Overall current scientific evidence suggests CGM formulation has improved bioavailability and tissue distribution of the biologically relevant unconjugated forms of turmeric actives called 'free' curcuminoids that may be responsible for the superior clinical outcomes reported with CGM treatments in comparison with unformulated standard curcumin across multiple studies.

Influence of CurQfen®-curcumin on cognitive impairment: a randomized, double-blinded, placebo-controlled, 3-arm, 3-sequence comparative study

Background

Although curcumin is a blood-brain-barrier permeable molecule with the ability to bind and segregate β-amyloid plaques and neurofibrillary tangles of hyperphosphorylated tau proteins, its poor oral bioavailability, rapid biotransformation to inactive metabolites, fast elimination from the systemic circulation, and hence the poor neuronal uptake has been limiting its clinical efficacy under neurodegenerative conditions.

Objective

We hypothesized that the highly bioavailable CurQfen-curcumin (CGM), which has been shown to possess significant blood-brain-barrier permeability and brain bioavailability, would ameliorate dementia in neurodegenerative conditions.

Methods

In the present double-blinded placebo-controlled 3-arm 3-sequence comparative study, 48 subjects characterized with moderate dementia due to the onset of Alzheimer's disease were randomized into three groups (N = 16/group) and supplemented with 400 mg × 2/day of either placebo (MCC), unformulated standard curcumin complex with 95% purity (USC), or CGM as a sachet for six months. The relative changes in cognitive and locomotor functions and biochemical markers were compared.

Results

Supplementation with CGM produced significant (P < 0.05) improvement in the Mini-Mental State Examination (MMSE) and the Geriatric Locomotive Function Scale (GLFS) scores in both intra- and inter-group comparison by 2 × 2 repeated measures (RM) ANOVA. Further, analysis of the serum levels of specific biomarkers (BDNF, Aβ42, tau protein, IL-6, and TNF-α) also revealed a significant (P < 0.05) improvement among CGM subjects as compared to placebo and the USC groups.

Conclusion

Supplementation with CGM as sachet was found to offer significant delay in the progress of Alzheimer's disease, as evident from the improvements in locomotive and cognitive functions related to dementia.

Clinical trial registration

http://ctri.nic.in, identifier: CTRI/2018/03/012410.

Two-Stage Supramolecular Self-Assembly-Directed Collagen-Peptide-Decorated Liposomal Complexes of Curcumin Microspheres with Enhanced Solubility and Bioavailability

Green formulations of phytonutrients with enhanced solubility and bioavailability are of great significance in nutrition therapy. In the present contribution, we hypothesized that the collagen peptides could be a safe, natural, food-grade, and cost-effective functional agent for the surface decoration and stabilization of liposomes in powder form and hence a "green" solution for the oral delivery of phytonutrients. The present study reports a two-stage supramolecular self-assembly-directed process for the preparation of collagen peptide-decorated liposomal complexes of curcumin (CCL) [10% (w/w)] as microspheres (125 ± 25 μm) with improved solubility (1.46 × 10⁵-fold) and sustained-release properties under gastrointestinal pH conditions. The molecular self-assembly of collagen peptides around the lipid bilayers and the various noncovalent interactions and conformational changes leading to the supramolecular assembly to act as a matrix for the encapsulation of lipid vesicles of curcumin were clear from the spectroscopic studies (UV-vis, fluorescence, FTIR, and circular dichroism). Further investigation of pharmacokinetics following a randomized double-blinded controlled trial on healthy volunteers (n = 15) demonstrated that the oral administration of 2.5 g of CCL sachet (250 mg of curcumin) enhanced the plasma concentration (C_max: 118 vs. 4.3 ng/mL), the elimination half-life (4.2 vs. 0.7 h), and bioavailability as per the area under the curve over 12 h [AUC_0-12h (CCL) = 506·8 vs. AUC_0-12h (C95) = 9.47 (53-fold)], when the plasma concentration of curcumin was estimated with triple quadruple tandem mass spectrometry (UPLC-ESI-MS/MS).

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.

A Sensitive Spectrofluorimetric Method for Curcumin Analysis

Curcumin (CUR), a natural polyphenolic compound extracted from the rhizomes of Curcuma longa, is used as a pharmaceutical agent, spice in food, and as a dye. Currently, CUR is being investigated for cancer treatment in Phase-II clinical trials. CUR also possesses excellent activities like anti-inflammatory, anti-microbial, and anti-oxidant, therefore quality control is crucial. The present research work was to develop a new, simple, validated and time-saving rapid 96-well plate spectrofluorimetric method for the determination of CUR. The developed method was compared with routinely used high performance liquid chromatography (HPLC) technique. The developed method were found to be linear in the concentration range of 15 to 3900 ng/mL with R2 ≥ 0.9983 for spectrofluorimetric and 50-7500 ng/mL with R2 ≥ 0.9999 for HPLC method. Accuracy, intraday and interday precision was adequate, with RSD lower than the suggested limits. The limits for the detection and the quantification of CUR were 7 and 15 ng/mL for spectrofluorimetric, and 25 and 50 ng/mL for HPLC respectively. The Bland-Altman analysis demonstrated the similarities between the two methods. The 96-well plate method was successfully applied to determine CUR in solid lipid nanoparticles (SLNs) and chitosan nanoparticles (Chi-NPs). The developed spectrofluorimetric method can hence serve as a possible replacement for the HPLC method for the quantification of CUR in healthcare and food products.

Micelle/Hydrogel Composite as a "Natural Self-Emulsifying Reversible Hybrid Hydrogel (N'SERH)" Enhances the Oral Bioavailability of Free (Unconjugated) Resveratrol

The poor oral bioavailability, rapid biotransformation to less active metabolites, and fast elimination from systemic circulation have been identified as the major limitations responsible for the clinical insignificance of many drug candidates and phytonutrients. Despite the technological advancements in the nanoformulations of synthetic drugs, there exist many challenges for nutritional therapy, due to the regulatory issues, use of high levels of synthetic emulsifiers and polymers, low stability, low loading levels, mainly liquid state, etc. Herein, we report the characterization and human pharmacokinetics of a natural self-emulsifying hybrid-hydrogel formulation of trans-resveratrol prepared by uniformly impregnating resveratrol micelles into the fenugreek galactomannan hydrogel scaffold to form a water-soluble micelle/hydrogel composite in powder form (RF-20). Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), particle size analysis by dynamic light scattering (DLS), and transmission electron microscopy (TEM) demonstrated the uniform impregnation of resveratrol micelles within the galactomannan hydrogel matrix to form a soluble (average particle size of 172.0 ± 10.4 nm and -21.0 ± 2.5 mV zeta potential) and amorphous powder form with smooth and translucent surface morphology for RF-20, with no chemical alterations. Upon pharmacokinetic studies on healthy human subjects (n = 16) following a randomized, double-blinded, placebo-controlled, 2-arm, 4-sequence crossover design and tandem mass spectrometry (UPLC-ESI-MS/MS), 80 mg of trans-resveratrol from RF-20 provided enhanced free resveratrol bioavailability and pharmacokinetic properties compared to the unformulated resveratrol with 98% purity. The enhancement in bioavailability was more when supplemented in sachet (12.98-fold) form than the capsule (10.48-fold) with improved absorption (C _max = 50.97 ± 15.82 ng/mL), circulation half-life (t _1/2 = 7.01 ± 1.44 h), and sustained delivery (T _max = 4.71 ± 0.73 h), as compared to the unformulated form (C _max = 15.07 ± 5.10 ng/mL; t _1/2 = 1.58 ± 0.65 h; T _max = 1.21 ± 0.42 h).

A novel bioavailable curcumin-galactomannan complex modulates the genes responsible for the development of chronic diseases in mice: A RNA sequence analysis

BACKGROUND

Chronic diseases or non-communicable diseases are a major burden worldwide due to the lack of highly efficacious treatment modalities and the serious side effects associated with the available therapies.

PURPOSE/STUDY DESIGN

A novel self-emulsifying formulation of curcumin with fenugreek galactomannan hydrogel scaffold as a water-dispersible non-covalent curcumin-galactomannan molecular complex (curcumagalactomannosides, CGM) has shown better bioavailability than curcumin and can be used for the prevention and treatment of chronic diseases. However, the exact potential of this formulation has not been studied, which would pave the way for its use for the prevention and treatment of multiple chronic diseases.

METHODS

The whole transcriptome analysis (RNAseq) was used to identify differentially expressed genes (DEGs) in the liver tissues of mice treated with LPS to investigate the potential of CGM on the prevention and treatment of chronic diseases. Expression analysis using DESeq2 package, GO, and pathway analysis of the differentially expressed transcripts was performed using UniProtKB and KEGG-KAAS server.

RESULTS

The results showed that 559 genes differentially expressed between the liver tissue of control mice and CGM treated mice (100 mg/kg b.wt. for 14 days), with adjusted p-value below 0.05, of which 318 genes were significantly upregulated and 241 were downregulated. Further analysis showed that 33 genes which were upregulated (log2FC > 8) in the disease conditions were significantly downregulated, and 32 genes which were downregulated (log2FC < -8) in the disease conditions were significantly upregulated after the treatment with CGM.

CONCLUSION

Overall, our study showed CGM has high potential in the prevention and treatment of multiple chronic diseases.

Mechanistic Insight into the Effects of Curcumin on Neuroinflammation-Driven Chronic Pain

Chronic pain is a persistent and unremitting condition that has immense effects on patients' quality of life. Studies have shown that neuroinflammation is associated with the induction and progression of chronic pain. The activation of microglia and astrocytes is the major hallmark of spinal neuroinflammation leading to neuronal excitability in the projection neurons. Excessive activation of microglia and astrocytes is one of the major contributing factors to the exacerbation of pain. However, the current chronic pain treatments, mainly by targeting the neuronal cells, remain ineffective and unable to meet the patients' needs. Curcumin, a natural plant product found in the Curcuma genus, improves chronic pain by diminishing the release of inflammatory mediators from the spinal glia. This review details the role of curcumin in microglia and astrocytes both in vitro and in vivo and how it improves pain. We also describe the mechanism of curcumin by highlighting the major glia-mediated cascades in pain. Moreover, the role of curcumin on inflammasome and epigenetic regulation is discussed. Furthermore, we discuss the strategies used to improve the efficacy of curcumin. This review illustrates that curcumin modulating microglia and astrocytes could assure the treatment of chronic pain by suppressing spinal neuroinflammation.

Action Mechanisms of Curcumin in Alzheimer's Disease and Its Brain Targeted Delivery

AD is a chronic neurodegenerative disease. Many different signaling pathways, such as Wnt/β-catenin, Notch, ROS/JNK, and PI3K/Akt/mTOR are involved in Alzheimer’s disease and crosstalk between themselves. A promising treatment involves the uses of flavonoids, and one of the most promising is curcumin; however, because it has difficulty permeating the blood–brain barrier (BBB), it must be encapsulated by a drug carrier. Some of the most frequently studied are lipid nanocarriers, liposomes, micelles and PLGA. These carriers are further conjugated with brain-targeting agents such as lactoferrin and transferrin. In this review paper, curcumin and its therapeutic effects, which have been examined in vivo, are analyzed and then the delivery systems to the brain are addressed. Overall, the analysis of the literature revealed great potential for curcumin in treating AD and indicated the challenges that require further research.

Safety assessment of a highly bioavailable curcumin-galactomannoside complex (CurQfen) in healthy volunteers, with a special reference to the recent hepatotoxic reports of curcumin supplements: A 90-days prospective study

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CGM did not cause adverse effects or significant variations in clinical parameters.

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Liver and renal function markers were in normal range after CGM supplementation.

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CGM was proved to be devoid of adjuvants, synthetic curcumin and contaminants.

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CGM has 100 % natural clean label status comprising vegan, allergen-free ingredients.

Recently, there is a growing concern about the use of curcumin supplements owing to a few reported hepatotoxicity related adverse events among some of the long-term consumers. Even though no clear evidence was elucidated for the suspected toxicity, the addition of adjuvants that inhibits body’s essential detoxification pathways, adulteration with synthetic curcumin, and presence of contaminants including heavy metals, chromate, illegal dyes, non-steroidal anti-inflammatory agents, and pyrrole alkaloids were suggested as plausible reasons. Considering these incidences and speculations, there is a need to critically evaluate the safety of curcumin supplements for prolonged intake. The present study is an evaluation of the safety of curcumin-galactomannoside complex (CGM), a highly bioavailable curcumin formulation with demonstrated high free curcuminoids delivery. Twenty healthy human volunteers were evaluated for toxic manifestations of CGM when supplemented with 1000 mg per day (∼380 mg curcuminoids) for 90-days. CGM supplementation did not cause any adverse effects or clinically significant variations in the vital signs, hematological parameters, lipid profile and renal function markers of the volunteers, indicating its safety. Liver function enzymes aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT) and bilirubin were in the normal range after 90-day supplementation of CGM. In summary, no adverse effects were observed under the conditions of the study. CGM can be considered as a safe curcumin supplement for regular consumption and is devoid of any adulterants or contaminants.

Brain regional pharmacokinetics following the oral administration of curcumagalactomannosides and its relation to cognitive function

OBJECTIVE

Though a number of bioavailable formulations of curcuminoids have been reported and available commercially as nutraceuticals for brain health, systematic informations on their blood-brain-barrier permeability and brain tissue distribution have not been reported. The present study was aimed to investigate the brain regional pharmacokinetics of curcuminoids following both single dose and repeated dose oral administration of a self-emulsifying food-grade formulation of curcuminoids using fenugreek galactomannan hydrogel scaffold as 'curcumagalactomannosides' (CGM), and its influence on cognitive functions in comparison with unformulated natural curcuminoids (NC) in Wistar rats.

METHODS

CGM was given to animals in single dose (100 mg curcuminoids/kg b. wt.) and repeated dose (100 mg curcuminoids/kg b. wt. for 28 days) and the concentration of total curcuminoids at various parts of brain was evaluated at different time points using Ultra-performance liquid chromatography/electrospray ionization triple quadruple tandem mass spectroscopy (UPLC-ESI-MS/MS) system. Another set of animals were also fed with CGM at single dose (100 mg curcuminoids/kg b. wt.) and repeated dose (100 mg curcuminoids/kg b. wt. for 28 days) and the behavioural studies were conducted using open field test and radial arm maze.

RESULTS

UPLC-ESI-MS/MS analyses of plasma revealed significant absorption of unconjugated (free) curcuminoids upon both single and repeated dose administration of CGM with maximum concentrations of 173.34 ± 27.12 ng/mL and 223.22 ± 32.73 ng/mL, respectively. Further analysis of brain tissues demonstrated significant blood-brain-barrier permeability. Brain regional pharmacokinetics (AUC, C_max and t_1/2) indicated a relative distribution order of hippocampus > striatum > cerebellum > cerebral cortex > brain stem. Supplementation of CGM for 28 days also offered significant (p  <  0.05) improvement in locomotor activity and reduction in spatial memory errors as compared to NC. The NC treatment also improved the behaviour better than the vehicle-treated group.

CONCLUSION

CGM could distribute significant amount of free curcuminoids, in brain especially in the hippocampus at both single and repeated dose administration with an elimination half-life of 2.6 h. CGM also showed a positive impact in behaviour of animals in comparison with normal unformulated curcuminoids.

The effects of oral administration of curcumin-galactomannan complex on brain waves are consistent with brain penetration: a randomized, double-blinded, placebo-controlled pilot study

OVERVIEW

A novel highly bioavailable curcumin-galactomannan (CGM) formulation was shown to have improved blood-brain-barrier (BBB) permeability of free curcuminoids in animal models; however, this has not been established in humans. The present study was conducted to determine the functional effects of CGM on brain waves in healthy individuals, owing to its BBB permeability.

METHODS

A total of 18 healthy volunteers aged 35-65 were randomly assigned to consume 500 mg CGM, Unformulated curcumin (UC) or Placebo capsules twice daily for 30 days. Electroencephalogram (EEG) measurements, audio-visual reaction time tests and a working memory test were conducted at baseline and after 30 days.

RESULTS

Supplementation of CGM resulted in a significant increase in α- and β-waves (p < 0.05) as well as a significant reduction in α/β ratio in comparison with unformulated curcumin and placebo groups. Furthermore, the CGM showed significant reduction in the audio-reaction time (29.8 %; p < 0.05) in comparison with placebo and 24.6% (p < 0.05) with unformulated curcumin. The choice-based visual-reaction time was also significantly decreased (36%) in CGM as compared to unformulated curcumin and placebo which produced 15.36% and 5.2% respectively.

CONCLUSION

The observed increase in α and β waves and reduction in α/β ratio in the CGM group suggest that CGM can influence the brain waves in healthy subjects in a manner consistent with penetration of the blood-brain-barrier. The EEG results correlated with improved audio-visual and working memory tests which further support the role of CGM on memory improvements and fatigue reduction.

Influence of a low-dose supplementation of curcumagalactomannoside complex (CurQfen) in knee osteoarthritis: A randomized, open-labeled, active-controlled clinical trial

A 6-week, randomized, open-label, active-controlled clinical trial was conducted to evaluate the influence of a low-dose curcumagalactomannosides (CGM) (400 mg once daily) in OA subjects. The treatment was compared with a standard combination of 500 mg glucosamine hydrochloride (GLN) and 415 mg chondroitin sulphate (CHN), supplied as a single oral dose twice a day. Out of 84 subjects randomized, 72 subjects who have completed the study were evaluated for the safety and efficacy of the treatments at baseline and subsequent visits (day 28 and 42), by measuring walking performance, VAS, KPS, and WOMAC scores. CGM exhibited 47.02, 21.43, and 206% improvement in VAS, KPS, and walking performance, respectively, compared to the baseline. Similarly, there was 31.17, 32.93, 36.44, and 35% improvement in the pain, stiffness, physical function, and total WOMAC scores. CGM also caused a substantial reduction in the serum inflammatory marker levels. The results indicate that a short-term supplementation of a low dosage CGM exerted superior beneficial effects than a high-dosage CHN-GLN combination in alleviating the pain and symptoms of OA subjects. Further clinical trials of extended duration in a larger population is required to substantiate the efficacy of CGM in the long-term management of OA.

Curcumagalactomannoside/Glucosamine Combination Improved Joint Health Among Osteoarthritic Subjects as Compared to Chondroitin Sulfate/Glucosamine: Double-Blinded, Randomized Controlled Study

Objective: A combination of curcumagalactomannosides (CGM) (400 mg) with glucosamine hydrochloride (GLN) (500 mg) was evaluated against a standard dietary supplement combination chondroitin sulfate (CHN) (415 mg)/GLN (500 mg) for their effectiveness in alleviating the pain and symptoms among osteoarthritic subjects. Design: Randomized, double-blinded and active-controlled study. Settings/Location: The study was conducted in a hospital-based research center in Vadodara, Gujarat, India. Subjects: Eighty subjects (38 males and 42 females), with confirmed osteoarthritis (OA) (Class I-III), were randomized into two parallel groups designated as Group I (CGM-GLN) and Group II (CHN-GLN). Interventions: All the study subjects were supplemented with their corresponding intervention capsules (ether CGM along with GLN or CHN along with GLN), as a single oral dose twice a day, once in the morning 10-15 min before breakfast and again in the evening before dinner, for 84 days. Outcome measures: A validated treadmill uphill walking protocol was used for the study, and the efficiency of supplementation was evaluated using visual analogue scale (VAS) score, Karnofsky Performance Scale (KPS) score, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire at the baseline, 28th, and 84th day following the treatment. Mechanism of action of CGM-GLN combination was analyzed by measuring the levels of serum inflammatory markers interleukin 1 beta (IL-1β), interleukin 6 (IL-6), and soluble vascular cell adhesion molecule-1 (sVCAM) at the baseline and 84th day. Results: CGM-GLN was found to offer significant beneficial effects to pain, stiffness, and physical function of OA subjects compared with CHN-GLN, which was evident from the improvement in walking performance, VAS score, KPS score, and WOMAC score. The efficiency of CGM-GLN was almost double compared with the CHN-GLN by the end of the study (84th day). A significant reduction of inflammatory serum marker levels was observed among CGM-GLN subjects compared with CHN-GLN subjects. Compared with the baseline, CGM-GLN produced 54.52%, 59.08%, and 22.03% reduction in IL-1β, IL-6, and sVCAM levels, respectively. Whereas CHN-GLN group of subjects expressed only 23.17%, 21.38%, and 6.82% reduction in IL-1β, IL-6, and sVCAM levels, respectively. Conclusions: In conclusion, the present study demonstrated the potential benefits of CGM-GLN supplements in alleviating the symptoms and function of OA subjects compared with the standard CHN-GLN treatment. The augmented efficacy of CGM-GLN combination could be attributed to the enhanced anti-inflammatory effect of CGM.

Influence of a Novel Food-Grade Formulation of Red Chili Extract (Capsicum annum) on Overweight Subjects: Randomized, Double-Blinded, Placebo-Controlled Study

Capsaicinoids from pungent red chilies (Capsicum annum and Capsicum frutescens) have received significant attention as a natural supplement for the management of obesity. However, the consumption of chili extract at physiologically relevant dosage of capsaicinoids is a challenge owing to its pungency and gastrointestinal discomforts. The present study reports the systemic absorption, safety and influence of a novel, food-grade, and sustained-release formulation of capsaicinoids-rich red chili extract using fenugreek dietary fiber (Capsifen^®). Twenty-four healthy overweight subjects were randomized into placebo (n = 12) and Capsifen (n = 12) groups and supplemented with 200 mg × 1/day of Capsifen (4 mg capsaicinoids/day) for 28 days. Influence of Capsifen on eating behavior and appetite was followed by Three-Factor Eating Questionnaire (TFEQ) and Council of Nutrition Appetite Questionnaire (CNAQ), respectively. Consumption of Capsifen did not reveal any adverse events or deviations in hematology and biochemical parameters related to safety. However, a significant decrease in body weight (2.1%), w/h ratio (4%) and body mass index (BMI) (2.2%) were observed among Capsifen group when compared to placebo. The TFEQ and appetite analysis revealed a significant improvement in uncontrolled eating and reduction in appetite among Capsifen subjects. The UPLC-ESI-MS/MS analysis confirmed the absorption of capsaicinoids from CAP supplementation. The study further demonstrated the safety and tolerability of Capsifen at the investigational dosage. Thus, the significant reduction in anthropometric parameters such as body weight, w/h ratio, and BMI along with the improvement in eating behaviour as well as appetite, indicated the potential body weight management effect of Capsifen.

Amelioration of Radiation-Induced Damages in Mice by Curcuminoids: The Role of Bioavailability

PURPOSE

The present study investigated the role of free curcuminoids bioavailability on the relative radioprotective efficacy of natural unformulated curcuminoids.

MATERIALS AND METHODS

A food-grade bioavailable formulation of curcuminoids as curcumagalactomannosides (CGM) and unformulated curcuminoids (UC) were employed for the study. Swiss albino mice were randomized into Normal control, Radiation control, Radiation + UC, and Radiation + CGM groups and irradiated with γ-radiation of 6, 8, 10 and 12 Gy. Survival rate, hematological and biochemical parameters, bone marrow cellularity, chromosomal aberrations and histopathology of intestine were followed as a measure of the relative efficacy.Results and Discussion: Oral administration with both UC and CGM at 100 mg/kg. b.wt. produced significant radioprotective effect over the untreated control group of animals. However, CGM treatment was found to provide better clastogenic and genotoxic potential as compared to UC. Further, the histopathology analysis of intestine confirmed the better protective effect of CGM over UC-treated animals.

CONCLUSION

The present study demonstrated the positive role of the bioavailability of curcuminoids in the amelioration of radiation-induced damages in mice since CGM treatment exerted better survival rate and radioprotective effect as compared with UC, despite the relatively low concentrations of curcuminoids in CGM (39% w/w).

Mechanism of the efflux transport of demethoxycurcumin-O-glucuronides in HeLa cells stably transfected with UDP-glucuronosyltransferase 1A1

Demethoxycurcumin (DMC) is a safe and natural food-coloring additive, as well as an agent with several therapeutic properties. However, extensive glucuronidation in vivo has resulted in its poor bioavailability. In this study, we aimed to investigate the formation of DMC-O-glucuronides by uridine 5'-diphospho-glucuronosyltransferase 1A1 (UGT1A1) and its transport by breast cancer resistance protein (BCRP) and multidrug resistance-associated proteins (MRPs) in HeLa cells stably transfected with UGT1A1 (named HeLa1A1 cells). The chemical inhibitors Ko143 (a selective BCRP inhibitor) and MK571 (a pan-MRP inhibitor) both induced an obvious decrease in the excretion rate of DMC-O-glucuronides and a significant increase in intracellular DMC-O-glucuronide concentrations. Furthermore, BCRP knock-down resulted in a marked reduction in the level of excreted DMC-O-glucuronides (maximal 55.6%), whereas MRP1 and MRP4 silencing significantly decreased the levels of excreted DMC-O-glucuronides (a maximum of 42.9% for MRP1 and a maximum of 29.9% for MRP3), respectively. In contrast, neither the levels of excreted DMC-O-glucuronides nor the accumulation of DMC-O-glucuronides were significantly altered in the MRP4 knock-down HeLa cells. The BCRP, MRP1 and MRP3 transporters were identified as the most important contributors to the excretion of DMC-O-glucuronides. These results may significantly contribute to improving our understanding of mechanisms underlying the cellular disposition of DMC via UGT-mediated metabolism.

Immunomodulators Inspired by Nature: A Review on Curcumin and Echinacea

The immune system is an efficient integrated network of cellular elements and chemicals developed to preserve the integrity of the organism against external insults and its correct functioning and balance are essential to avoid the occurrence of a great variety of disorders. To date, evidence from literature highlights an increase in immunological diseases and a great attention has been focused on the development of molecules able to modulate the immune response. There is an enormous global demand for new effective therapies and researchers are investigating new fields. One promising strategy is the use of herbal medicines as integrative, complementary and preventive therapy. The active components in medical plants have always been an important source of clinical therapeutics and the study of their molecular pharmacology is an enormous challenge since they offer a great chemical diversity with often multi-pharmacological activity. In this review, we mainly analysed the immunomodulatory/antinflammatory activity of Echinacea spp. and Curcuma longa, focusing on some issues of the phytochemical research and on new possible strategies to obtain novel agents to supplement the present therapies.

Mulakal J, Maliakel BP, Krishnakumar IM. A Novel Curcumin-Galactomannoside Complex Delivery System Improves Hepatic Function Markers in Chronic Alcoholics: A Double-Blinded, randomized, Placebo-Controlled Study

Considering the recent interest in free (unconjugated) curcuminoids delivery, the present study investigated the efficacy of a novel food-grade free-curcuminoids delivery system (curcumin-galactomannoside complex; CGM) in improving the hepatic function markers (inflammation and oxidative stress) in chronic alcoholics. The double-blinded, placebo-controlled study randomized 48 subjects with elevated serum transaminases and gamma-glutamyl transferase (GGT) levels, who were allocated to two groups (n=24) and to receive either placebo or CGM at (250 mg × 2)/day for 8 weeks. While liver function markers (transaminases and GGT) in the placebo group showed an increase (~ 9.5%), CGM group indicated a significant decrease in transaminases (31%) and GGT (29%) from the baseline levels. The beneficial effect of CGM was also clear from the significant increase (p <0.001) in endogenous antioxidants (GSH, SOD, and GPx) and decrease in inflammatory markers (IL-6 and CRP) levels (p <0.001) as compared to both the baseline and placebo group. To summarize, the nutritional intervention of CGM-curcumin was found to offer a significant hepatoprotective effect to attenuate the alcohol induced alterations to hepatic function markers. The Indian Medical Council and Drug Controller General of India approved Clinical Trial Registry No. CTRI/2018/03/012385.

Simultaneous quantification of free curcuminoids and their metabolites in equine plasma by LC-ESI-MS/MS

The human health benefits attributed to turmeric/curcumin spice has resulted in its wide utilization as a dietary supplement for companion pets and other animals including horses. While the quantification of free curcuminoids (curcumin, demethoxycurcumin, bisdemethoxycurcumin) and their phase-2 metabolites (curcumin-O-sulfate, curcumin-O-glucuronide) have been extensively investigated in human and rodent biological samples (primarily plasma and serum), there is lack of similar data for horses. Herein, we report a validated LC-ESI-MS/MS method for the simultaneous quantification of the aforementioned free curcuminoids and their metabolites in equine plasma. The linearity of the aforementioned curcuminoids and curcumin-O-sulfate was in the range of 0.5-1000 ng/mL and 1-1000 ng/mL for curcumin-O-glucuronide with 85-115% accuracy and <15% precision in equine plasma. The method was validated based on US FDA criteria and applied to characterize the pharmacokinetics of curcumin-O-sulfate in equine plasma.

Safety, Tolerance, and Enhanced Efficacy of a Bioavailable Formulation of Curcumin With Fenugreek Dietary Fiber on Occupational Stress: A Randomized, Double-Blind, Placebo-Controlled Pilot Study

Drug delivery systems capable of delivering free (unconjugated) curcuminoids is of great therapeutic significance, since the absorption of bioactive and permeable form plays a key factor in mediating the efficacy of a substance which undergoes rapid biotransformation. Considering the recent understanding on the relatively high bioactivities and blood-brain-barrier permeability of free curcuminoids over their conjugated metabolites, the present human study investigated the safety, antioxidant efficacy, and bioavailability of CurQfen (curcumagalactomannoside [CGM]), a food-grade formulation of natural curcumin with fenugreek dietary fiber that has shown to possess improved blood-brain-barrier permeability and tissue distribution in rats. In this randomized double-blinded and placebo-controlled trial, 60 subjects experiencing occupational stress-related anxiety and fatigue were randomized to receive CGM, standard curcumin, and placebo for 30 days (500 mg twice daily). The study demonstrated the safety, tolerance, and enhanced efficacy of CGM in comparison with unformulated standard curcumin. A significant improvement in the quality of life (P < 0.05) with considerable reduction in stress (P < 0.001), anxiety (P < 0.001), and fatigue (P < 0.001) was observed among CGM-treated subjects as compared with the standard curcumin group, when monitored by SF-36, Perceived Stress Scale with 14 items, and Beck Anxiety Inventory scores. Improvement in the quality of life was further correlated with the significant enhancement in endogenous antioxidant markers (P < 0.01) and reduction in lipid peroxidation (P < 0.001). Further comparison of the free curcuminoids bioavailability after a single-dose (500 mg once per day) and repeated-dose (500 mg twice daily for 30 days) oral administration revealed enhanced absorption and improved pharmacokinetics of CGM upon both single- (30.7-fold) and repeated-dose (39.1-fold) administrations.