Beyond Yellow Curry: Assessing Commercial Curcumin Absorption Technologies

Investigating the impact of nanoemulsion of curcumin-loaded olive oil on growth performance, feed utilization, immunological responses, and redox status of Litopenaeus vannamei shrimp with emphasis on economic efficiency of supplementation

The trail aimed to explore the effect of dietary supplementation of curcumin loaded olive oil nanoemulsion (CUR-OLNE) on growth performance, feed utilization, blood biochemical, redox status, and immune response of Litopenaeus vannamei shrimp, considering the economic efficiency of supplementation. A total of 280 healthy shrimps (3.42 ± 0.02 g) were randomly distributed into five equal groups and were fed diets containing 0 (CUR-OLNE0), 5(CUR-OLNE5), 10(CUR-OLNE10), 15(CUR-OLNE15) and 20 (CUR-OLNE20) mg CUR-OLNE/kg diet, respectively for 16 weeks. Among CUR-OLNE treated groups, CUR-OLNE20 showed the highest growth performance and feed utilization traits, including final body weight, specific growth rate, feed conversion ratio, and protein efficiency ratio. Notably, the photomicrographs provided further compelling evidence regarding the potential effect of CUR-OLNE supplementation on muscle structure and integrity. Compared to the control, the levels of blood protein significantly induced in CUR-OLNE15 and CUR-OLNE20 treated groups (p < 0.05). All CUR-OLNE -supplemented groups possessed lower activities of liver enzymes as well as the levels of urea and creatinine compared to the control (p < 0.05). The addition of 20 mg CUR-OLNE/kg diet decreased the concentrations of cortisol, glucose and triglycerides. The dietary treatment significantly improved the secretion of digestive enzymes, including amylase, lipase, and protease. The lowest levels of Malondialdehyde and the highest levels of total antioxidant capacity, super oxide dismutase, catalase, lysozyme and immunoglobulin M were detected in both of CUR-OLNE15, and CUR-OLNE20 treated groups compared to the control (p < 0.05). There were considerable significant effects of dietary supplementation of CUR-OLNE on economic efficiency. In conclusion, the application of nanocarriers for the delivery of dietary immune stimulants such as CUR-OLNE to Litopenaeus vannamei shrimp is a promising strategy for improving shrimp nutrition. The addition of 20 mg CUR-OLNE/kg to the diets of can be recommended as an affective intervention to improve growth performance, feed utilization, and health status of shrimp. Implementing this intervention can maximize the economic efficiency of shrimp farming while promoting sustainable practices in the industry.

Characterization and Therapeutic Potential of Curcumin-Loaded Cerium Oxide Nanoparticles for Interstitial Cystitis Management

Oxidative stress resulting from reactive oxygen species (ROS) is often considered to be the leading cause of interstitial cystitis (IC), which is a chronic inflammatory disease. Antioxidants have been proven to have promising therapeutic effects on IC. In this study, we present an antioxidant intervention for IC by introducing curcumin-loaded cerium oxide nanoparticles (Cur-CONPs). Recognizing oxidative stress as the primary contributor to IC, our research builds on previous work utilizing cerium oxide nanoparticles (CONPs) for their outstanding antioxidant and anti-inflammatory properties. However, given the need to effectively relieve acute inflammation, we engineered Cur-CONPs to harness the short-term radical-scavenging antioxidant prowess of curcumin. Through in vitro studies, we demonstrate that the Cur-CONPs exhibit not only robust antioxidant capabilities but also superior anti-inflammatory properties over CONPs alone. Furthermore, in vivo studies validate the therapeutic effects of Cur-CONPs on IC. Mice with IC subjected to the Cur-CONP treatment exhibited improved micturition behaviors, relief from pelvic pain sensitivity, and reduced expression of inflammatory proteins (IL-6, IL-1β, TNF-α, Cox2). These findings suggest that the synergistic antioxidant properties of the Cur-CONPs that combine the sustained antioxidant properties of CONPs and acute anti-inflammatory capabilities of curcumin hold promise as a novel treatment strategy for IC.

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.

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.

Efficacy and safety of curcuminoids alone in alleviating pain and dysfunction for knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Curcuminoids (CURs) are the principal ingredients of Curcuma longa L. [Zingiberaceae] (CL)-an herbal plant used in east Asia to alleviate pain and inflammation. Thus far, the therapeutic effects of CURs for knee osteoarthritis (OA) uncovered by multiple reviews remained uncertain due to broadly involving trials with different agents-combined or CURs-free interventions. Therefore, we formed stringent selection criteria and assessment methods to summarize current evidence on the efficacy and safety of CURs alone in the treatment of knee OA.

METHODS

A series of databases were searched for randomized controlled trials (RCTs) evaluating the efficacy and safety of CURs for knee OA. Clinical outcomes were evaluated using meta-analysis and the minimum clinically important difference (MCID) for both statistical and clinical significance.

RESULTS

Fifteen studies with 1670 patients were included. CURs were significantly more effective than placebo in the improvements of VAS for pain ( WMD: - 1.77, 95% CI: - 2.44 to - 1.09), WOMAC total score ( WMD: - 7.06, 95% CI: - 12.27 to - 1.84), WOMAC pain score ( WMD: - 1.42, 95% CI: - 2.41 to - 0.43), WOMAC function score ( WMD: - 5.04, 95% CI: - 7.65 to - 2.43), and WOMAC stiffness score ( WMD: - 0.54, 95% CI: - 1.03 to - 0.05). Meanwhile, CURs were not inferior to NSAIDs in the improvements of pain- and function-related outcomes. Additionally, CURs did not significantly increase the incidence of adverse events (AEs) compared with placebo ( RR: 1.03, 95% CI: 0.69 to 1.53, P = 0.899, I2 = 23.7%) and NSAIDs (RR: 0.71 0.65, 95% CI: 0.57 0.41 to 0.90 1.03).

CONCLUSIONS

CURs alone can be expected to achieve considerable analgesic and functional promotion effects for patients with symptomatic knee OA in short term, without inducing an increase of adverse events. However, considering the low quality and substantial heterogeneity of present studies, a cautious and conservative recommendation for broader clinical use of CURs should still be made. Further high-quality studies are necessary to investigate the impact of different dosages, optimization techniques and administration approaches on long-term safety and efficacy of CURs, so as to strengthen clinical decision making for patients with symptomatic knee OA.

Neuroprotective potential of curcuminoids in modulating Alzheimer's Disease via multiple signaling pathways

Alzheimer's disease (AD) is a progressive and frequent neurodegenerative disease of elderly people. In the 21st century, owing to the increasing prevalence of AD, there is a crucial need for finding better and effective pharmacotherapeutic approaches. This review article demonstrated the various sources and possible metabolic pathways of curcuminoids obtained from Curcuma longa herb, to prevent and treat AD but the information related to the metabolic fate of curcuminoids is deficient. Different in vitro and in vivo research studies demonstrating the mechanisms by which curcuminoids attenuated AD have been summarized. Administration of curcuminoids has been indicated to inhibit hyperphosphorylation of tau protein, deposition, and oligomerization of amyloid beta plaques in several AD models. Curcuminoids also chelate metals and form complexes, have antioxidant properties, mediates neuroinflammatory signaling pathways by modifying microglial cells activity, inhibit acetylcholinesterase activities and also modulates other associated signaling pathways including insulin signaling pathways and heme-oxygenase pathway. Briefly curcuminoids exhibit the capability to be more productive and efficacious compared to many recent treatments due to their antioxidant, delayed neuron degeneration and anti-inflammatory potential. Although their effectiveness as a curative agent is considered to be reduced due to their low bioavailability, If the issue of curcuminoids' low bioavailability is resolved then curcuminoid-based medications are hopefully on the horizon against AD.

A rare association between factor H deficiency and lupus: Case report and experimental treatment with curcumin

Factor H (FH) is one of the most important regulatory proteins of the alternative pathway of the complement system. FH deficiency is a rare condition that causes unregulated C3 consumption, leading to an increased susceptibility to infections and glomerulopathies. Our previous studies have demonstrated a FH deficient patient carrying a c.452G > A, p.R127H FH mutation which leads to a misfolded protein and its retention in the endoplasmic reticulum. In his cultured fibroblasts, FH-delayed secretion was partially rescued when treated with curcumin, and once secreted, exhibited normal regulatory function. Here, we report a childhood-onset systemic lupus erythematosus (cSLE) in this FH deficient patient and the results of experimental treatment with curcumin aiming to rescue FH secretion and regulatory activity.

Steatosis induced by nonylphenol in HepG2 cells and the intervention effect of curcumin

Non-alcoholic fatty liver disease (NAFLD) has increasingly become a serious public health problem. There is growing evidence that nonylphenol (NP) exposure may cause steatosis, but the underlying mechanism is not fully understood. Curcumin (CUR) improves NAFLD-related lipid metabolism disorders and oxidative stress, but its preventive and therapeutic effects on NP-induced steatosis have not been reported. The objective of this investigation was to determine the capability and potential mechanism of NP to induce steatosis in vitro and the intervention of curcumin. HepG2 cells were treated with 0 μM, 20 μM, 30 μM, 40 μM NP for 24 h. Lipid droplets accumulated significantly in HepG2 cells after NP treatment, and the concentration of triglyceride (TG) and total cholesterol (T-CHO) increased significantly. Simultaneously, lipogenesis gene expression was up-regulated significantly, fatty acid oxidation (FAO) gene expression was significantly down-regulated, and reactive oxygen species (ROS) were overproduced. Meanwhile, the expression of p-AMPK/AMPK in the AMPK/mTOR signaling pathway was significantly down-regulated and the expression of p-mTOR/mTOR was markedly up-regulated. However, blocking ROS production with N-acetyl-L-cysteine (NAC) can reverse these phenomena. In addition, our study found that curcumin effectively ameliorated the effects of NP-induced steatosis. Our study indicates that NP can induce steatosis in HepG2 cells, and may be implicated in inhibiting the ROS-dependent AMPK/mTOR pathway, and that curcumin ameliorates the NAFLD-like changes induced by NP in HepG2 cells.

Improving Curcumin Bioavailability: Current Strategies and Future Perspectives

Curcumin possesses a plethora of interesting pharmacological effects. Unfortunately, it is also characterized by problematic drug delivery and scarce bioavailability, representing the main problem related to the use of this compound. Poor absorption, fast metabolism, and rapid systemic clearance are the most important factors contributing to low curcumin levels in plasma and tissues. Accordingly, to overcome these issues, numerous strategies have been proposed and are investigated in this article. Due to advances in the drug delivery field, we describe here the most promising strategies for increasing curcumin bioavailability, including the use of adjuvant, complexed/encapsulated curcumin, specific curcumin formulations, and curcumin nanoparticles. We analyze current strategies, already available in the market, and the most advanced technologies that can offer a future perspective for effective curcumin formulations. We focus the attention on the effectiveness of curcumin-based formulations in clinical trials, providing a comprehensive summary. Clinical trial results, employing various delivery methods for curcumin, showed that improved bioavailability corresponds to increased therapeutic efficacy. Furthermore, advances in the field of nanoparticles hold great promise for developing curcumin-based complexes as effective therapeutic agents. Summarizing, suitable delivery methods for this polyphenol will ensure the possibility of using curcumin-derived formulations in clinical practice as preventive and disease-modifying therapeutics.

The enhanced bioavailability of free curcumin and bioactive-metabolite tetrahydrocurcumin from a dispersible, oleoresin-based turmeric formulation

BACKGROUND

Curcuminoids have been widely studied for human health and disease applications, yet bioavailability remains a hurdle to actualizing all the benefits ascribed to them. The lack of standardization in analysis method, confusion about what constitutes an ideal analyte, and conflicting thoughts around dosing strategies have made it difficult to draw parity between bioavailability and bioactivity and establish a baseline for formulation comparisons.

METHODS

This randomized double-blinded, 2-way cross over, single oral dose, comparative bioavailability study differentially evaluates curcumin at the time of its absorption and along various biotransformation pathways, to include free curcumin, the readily usable form of curcumin; individual and composite totals of curcumin and its analogues as exogenously cleaved conjugates, for example, total curcumin, total demethoxycurcumin (DMC), total bisdemethoxycurcumin (BDMC), and total curcuminoids respectively; and the bioactive metabolite of curcumin, total tetrahydrocurcumin (THC). As a primary study objective, the relative bioavailability of CURCUGEN, a novel dispersible, 50% curcuminoids-concentrated turmeric extract was compared to the standard curcumin reference product, curcuminoids 95% standardized extract (C-95), using the maximum concentration (Cmax), and area under the curve (AUC0-t) of free curcumin, total curcumin, total DMC, total BDMC and the curcumin active metabolite, as total THC.

RESULTS

The evaluation of free curcumin demonstrated that the Cmax and AUC0-t of the CURCUGEN was 16.1 times and 39 times higher than the Cmax and AUC0-t of C-95. Furthermore, total curcumin, total DMC, total BDMC, and total curcuminoids resulted in AUC0-t of the CURCUGEN at 49.5-, 43.5-, 46.8-, and 52.5-fold higher than C-95, respectively. The relative bioavailability of CURCUGEN for total THC was found to be 31 times higher when compared to C-95.

CONCLUSION

As the first human pharmacokinetics study to apply best-practice recommendations and pharmaceutically-aligned guidance in the comprehensive evaluation of a novel curcuminoids formulation, we have established the novelty of said formulation while better standardizing for the common variances and discrepancies between curcuminoids and their derivatives in the literature and commercial marketing, alike.

Effects of Curcumin and Its Different Formulations in Preclinical and Clinical Studies of Peripheral Neuropathic and Postoperative Pain: A Comprehensive Review

Lesion or disease of the somatosensory system leads to the development of neuropathic pain. Peripheral neuropathic pain encompasses damage or injury of the peripheral nervous system. On the other hand, 10–15% of individuals suffer from acute postoperative pain followed by persistent pain after undergoing surgeries. Antidepressants, anticonvulsants, baclofen, and clonidine are used to treat peripheral neuropathy, whereas opioids are used to treat postoperative pain. The negative effects associated with these drugs emphasize the search for alternative therapeutics with better efficacy and fewer side effects. Curcumin, a polyphenol isolated from the roots of Curcuma longa, possesses antibacterial, antioxidant, and anti-inflammatory properties. Furthermore, the low bioavailability and fast metabolism of curcumin have led to the advent of various curcumin formulations. The present review provides a comprehensive analysis on the effects of curcumin and its formulations in preclinical and clinical studies of neuropathic and postoperative pain. Based on the positive outcomes from both preclinical and clinical studies, curcumin holds the promise of mitigating or preventing neuropathic and postoperative pain conditions. However, more clinical studies with improved curcumin formulations are required to involve its use as adjuvant to neuropathic and postoperative drugs.

Comparative bioavailability of curcuminoids from a water-dispersible high curcuminoid turmeric extract against a generic turmeric extract: a randomized, cross-over, comparative, pharmacokinetic study

OBJECTIVES

The therapeutic utility of turmeric (Curcuma longa L., Zingiberaceae) is limited due to low bioavailability of its active principal curcuminoids. This study evaluates the pharmacokinetic characteristics of a natural, water-dispersible turmeric extract containing 60% curcuminoids (TurmXtra 60N), referred to as WDTE60N, compared to standard turmeric extract 95% (STE95).

METHODS

This open-label, two-way crossover, single oral dose, comparative pharmacokinetic study, randomized 14 subjects to receive one capsule of WDTE60N (150 mg curcuminoids) or three capsules of STE95 (500 mg curcuminoids each). The resulting dose ratio of actives for WDTE60N:STE95 was 1:10.

KEY FINDINGS

Peak plasma levels of free curcumin, total curcuminoids, tetrahydrocurcumin and demethoxycurcumin were similar (P > 0.05). Cmax of total curcumin was higher (P = 0.0253) for WDTE60N at a 10-fold lower dose compared to STE95 (43.5 ± 28.5 vs. 21.3 ± 10.7 ng/ml). Mean AUC0-t was higher (P < 0.001) for free curcumin and comparable for total curcumin and total curcuminoids with WDTE60N than with STE95. Five adverse events were reported in three subjects (mild in severity) and were unrelated to study products.

CONCLUSION

WDTE60N showed higher absorption and comparable exposure for free curcumin, total curcumin and total curcuminoids at a 10-fold lower dose than STE95.

Curcumin and its analog alleviate diabetes-induced damages by regulating inflammation and oxidative stress in brain of diabetic rats

BACKGROUND

Diabetic encephalopathy is a severe diabetes complication with cognitive dysfunction and neuropsychiatric disability. The mechanisms underlying diabetic encephalopathy is believed to be relevant with oxidative stress, vascular amylin deposition, immune receptors, inflammation, etc. This study wanted to evaluate the ability of curcumin and its analog A13 to alleviate oxidative stress and inflammation in diabetes-induced damages in brain.

METHODS

Sixty adult male Sprague-Dawley rats were divided into 5 groups: normal control (NC) group, diabetes mellitus (DM) group, curcumin-treated diabetes mellitus (CUR) group, high dose of A13-treated diabetes mellitus (HA) group, low dose of A13-treated diabetes mellitus (LA) group. Activation of the nuclear factor kappa-B (NF-κB p65) pathway was detected by RT-qPCR, immunohistochemical (IHC) staining and Western blot; oxidative stress was detected by biochemical detection kit; brain tissue sections were stained with hematoxylin-eosin (HE) staining and Myelin staining.

RESULTS

RT-qPCR, IHC staining and Western blot showed that curcumin and A13 treatment could inhibit the NF-κB p65 pathway. Curcumin and A13 increased the activity of superoxide dismutase and decreased the malondialdehyde level in the brain of diabetic rats. Furthermore, HE staining and Myelin staining demonstrated that the histological lesions of the brain in diabetic rats could be significantly ameliorated by curcumin and A13.

CONCLUSION

Curcumin analog A13 could alleviate the damages in the brain of diabetes rats by regulating the pathways of inflammation and oxidative stress. A13 may be a new potential therapeutic agent for diabetic encephalopathy.

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.

An Update on the Pharmacological Usage of Curcumin: Has it Failed in the Drug Discovery Pipeline?

The pharmacological propensities of curcumin have been reported in a plethora of pre-clinical and clinical studies. However, innate attributes account for extremely low oral bioavailability which impedes its development as a therapeutic agent. Regardless, these drawbacks have not deterred researchers from optimizing its potentials. This review discussed the pharmacokinetic properties of curcumin relative to its outlook as a lead compound in drug discovery. Also, we highlighted therapeutic strategies that have expedited improvements in curcumin oral bioavailability and delivery to target sites over the years. Recent implementations of these strategies were also covered. More research efforts should be directed towards investigating the pharmacokinetic impacts of these novel curcumin formulations in human clinical studies since inter-species disparities could limit the accuracies of animal studies. We envisaged that integrative-clinical research would help determine 'actual' improvements in curcumin pharmacokinetics coupled with suitable administrative routes, optimal dosing, and drug-enzyme or drug-drug interactions. In addition, this could help determine formulations for achieving higher systemic exposure of parent curcumin thereby providing a strong impetus towards the development of curcumin as a drug candidate in disease treatment.

Modulating disease-relevant tau oligomeric strains by small molecules

The pathological aggregation of tau plays an important role in Alzheimer's disease and many other related neurodegenerative diseases, collectively referred to as tauopathies. Recent evidence has demonstrated that tau oligomers, small and soluble prefibrillar aggregates, are highly toxic due to their strong ability to seed tau misfolding and propagate the pathology seen across different neurodegenerative diseases. We previously showed that novel curcumin derivatives affect preformed tau oligomer aggregation pathways by promoting the formation of more aggregated and nontoxic tau aggregates. To further investigate their therapeutic potential, we have extended our studies o disease-relevant brain-derived tau oligomers (BDTOs). Herein, using well-characterized BDTOs, isolated from brain tissues of different tauopathies, including Alzheimer's disease, progressive supranuclear palsy, and dementia with Lewy bodies, we found that curcumin derivatives modulate the aggregation state of BDTOs by reshaping them and rescue neurons from BDTO-associated toxicity. Interestingly, compound CL3 showed an effect on the aggregation pattern of BDTOs from different tauopathies, resulting in the formation of less neurotoxic larger tau aggregates with decreased hydrophobicity and seeding propensity. Our results lay the groundwork for potential investigations of the efficacy and beneficial effects of CL3 and other promising compounds for the treatment of tauopathies. Furthermore, CL3 may aid in the development of tau imaging agent for the detection of tau oligomeric strains and differential diagnosis of the tauopathies, thus enabling earlier interventions.

Highly Bioavailable Forms of Curcumin and Promising Avenues for Curcumin-Based Research and Application: A Review

Curcumin exerts a wide range of beneficial physiological and pharmacological activities, including antioxidant, anti-amyloid, anti-inflammatory, anti-microbial, anti-neoplastic, immune-modulating, metabolism regulating, anti-depressant, neuroprotective and tissue protective effects. However, its poor solubility and poor absorption in the free form in the gastrointestinal tract and its rapid biotransformation to inactive metabolites greatly limit its utility as a health-promoting agent and dietary supplement. Recent advances in micro- and nano-formulations of curcumin with greatly enhanced absorption resulting in desirable blood levels of the active forms of curcumin now make it possible to address a wide range of potential applications, including pain management, and as tissue protective. Using these forms of highly bioavailable curcumin now enable a broad spectrum of appropriate studies to be conducted. This review discusses the formulations designed to enhance bioavailability, metabolism of curcumin, relationships between solubility and particle size relative to bioavailability, human pharmacokinetic studies involving formulated curcumin products, the widely used but inappropriate practice of hydrolyzing plasma samples for quantification of blood curcumin, current applications of curcumin and its metabolites and promising directions for health maintenance and applications.

Toxic Tau Oligomers Modulated by Novel Curcumin Derivatives

The pathological aggregation and accumulation of tau, a microtubule-associated protein, is a common feature amongst more than 18 different neurodegenerative diseases that are collectively known as tauopathies. Recently, it has been demonstrated that the soluble and hydrophobic tau oligomers are highly toxic in vitro due to their capacity towards seeding tau misfolding, thereby propagating the tau pathology seen across different neurodegenerative diseases. Modulating the aggregation state of tau oligomers through the use of small molecules could be a useful therapeutic strategy to target their toxicity, regardless of other factors involved in their formation. In this study, we screened and tested a small library of newly synthesized curcumin derivatives against preformed recombinant tau oligomers. Our results show that the curcumin derivatives affect and modulate the tau oligomer aggregation pathways, converting to a more aggregated non-toxic state as assessed in the human neuroblastoma SH-SY5Y cell line and primary cortical neuron cultures. These results provide insight into tau aggregation and may become a basis for the discovery of new therapeutic agents, as well as advance the diagnostic field for the detection of toxic tau oligomers.

Encapsulated Curcumin Enhances Intestinal Absorption and Improves Hepatic Damage in Alcoholic Liver Disease-Induced Rats

Encapsulated curcumin (ENCC) was prepared from a commercial curcuminoids complex and was evaluated for its intestinal permeability and hepatoprotective effects. Intestinal permeability was evaluated using a Caco-2 intestinal cell monolayer system and the non-everted gut sac method. The hepatoprotective effect was evaluated in experimental rats administered alcohol for 4 weeks. The intestinal permeability results suggested that encapsulation is a useful method for enhancing adsorption of curcumin via the intestinal epithelium. ENCC administration resulted in the significant reduction of various serum indicators. Notably, most of the indicators elevated by ethanol decreased below normal levels when rats were administered a high dose of ENCC. Oral administration of ENCC also augmented the activity of glutathione peroxidase in the liver, and both normal curcumin and ENCC significantly alleviated high levels of malondialdehyde. Our results demonstrate a significant hepatoprotective effect of ENCC in vivo owing to its ability to improve bioavailability of curcumin.

The fallacy of enzymatic hydrolysis for the determination of bioactive curcumin in plasma samples as an indication of bioavailability: a comparative study

BACKGROUND

Numerous health benefits have been demonstrated for curcumin which is extracted from turmeric (Curcuma longa L). However, due to its poor absorption in the free form in the gastrointestinal tract and rapid biotransformation, various formulations have been developed to enhance its bioavailability. Previous studies indicate that the free form of curcumin is more bioactive than its conjugated counterparts in target tissues. Most curcumin pharmacokinetics studies in humans designed to assess its absorption and bioavailability have measured and reported total (free plus conjugated) curcumin, but not free, bioactive curcumin in the plasma because enzymatic hydrolysis was employed prior to its extraction and analysis. Therefore, the bioavailability of free curcumin cannot be determined.

METHODS

Eight human subjects (4 male, 4 female) consumed a single dose of 400 mg curcumin in an enhanced absorption formulation, and blood samples were collected over 6 h. Plasma was treated either with or without glucuronidase/sulfatase prior to extraction. Curcumin and its major metabolites were analyzed using HPLC-tandem mass spectrometry. In addition, the literature was searched for pharmacokinetic studies involving curcumin using PubMed and Google Scholar, and the reported bioavailability data were compared based on whether hydrolysis of plasma samples was used prior to sample analysis.

RESULTS

Hydrolysis of blood plasma samples prior to extraction and reporting the results as "curcumin" obscures the amount of free, bioactive curcumin and total curcuminoids as compared to non-hydrolyzed samples. As a consequence, the data and biological effects reported by most pharmacokinetic studies are not a clear indication of enhanced plasma levels of free bioactive curcumin due to product formulations, leading to a misrepresentation of the results of the studies and the products when enzymatic hydrolysis is employed.

CONCLUSIONS

When enzymatic hydrolysis is employed as is the case with most studies involving curcumin products, the amount of free bioactive curcumin is unknown and cannot be determined. Therefore, extreme caution is warranted in interpreting published analytical results from biological samples involving ingestion of curcumin-containing products.

TRIAL REGISTRATION

ClinicalTrails.gov, trial identifying number NCT04103788 , September 24, 2019. Retrospectively registered.

Curcumin Alleviates β Amyloid-Induced Neurotoxicity in HT22 Cells via Upregulating SOD2

Curcumin protects neuronal cells exposed to β amyloid (Aβ); the mechanism, however, is still obscure. The aim of this study is to determine whether the type 2 superoxide dismutase (SOD2) mediates curcumin-induced protective effects in Aβ-treated neuronal cells. In this study, the HT22 neuronal cells were exposed to Aβ to imitate neuronal injury in Alzheimer's disease (AD). After 24-h treatment, 10 μM Aβ decreased cell viability and mitochondrial functions, including mitochondrial complex activities and mitochondrial membrane potential (MMP), and also downregulated anti-oxidants SOD2, glutathione (GSH), and catalase (CAT) levels (P < 0.05), meanwhile, increased lactic dehydrogenase (LDH) release, apoptosis level, intracellular reactive oxygen species (ROS) and mitochondrial superoxide accumulation (P < 0.05). And, co-administration of 1 μM curcumin significantly reduced the Aβ-induced cell injury and oxidative damage above (P < 0.05). Downregulating SOD2 by using small interfering RNA (siRNA), however, significantly abolished the curcumin-induced protective and anti-oxidative effects in HT22 cells (P < 0.05); the scramble (SC)-siRNA did not cause marked effects on the curcumin-induced protective effects (P > 0.05). These findings showed that curcumin can alleviate Aβ-induced injury in neuronal cells, and SOD2 protein may mediate the neuroprotective effects.

Synergistic inhibitory effects of cetuximab and curcumin on human cisplatin-resistant oral cancer CAR cells through intrinsic apoptotic process

Cetuximab, an epidermal growth factor receptor (EGFR)-targeting monoclonal antibody (mAb), is a novel targeted therapy for the treatment of patients with oral cancer. Cetuximab can be used in combination with chemotherapeutic agents to prolong the overall survival rates of patients with oral cancer. Curcumin is a traditional Chinese medicine, and it has been demonstrated to have growth-inhibiting effects on oral cancer cells. However, information regarding the combination of cetuximab and curcumin in drug-resistant oral cancer cells is lacking, and its underlying mechanism remains unclear. The purpose of the present study was to explore the oral anticancer effects of cetuximab combined with curcumin on cisplatin-resistant oral cancer CAR cell apoptosis in vitro. The results demonstrated that combination treatment synergistically potentiated the effect of cetuximab and curcumin on the suppression of cell viability and induction of apoptosis in CAR cells. Cetuximab and curcumin combination induced apoptosis and dramatically increased caspase-3 and caspase-9 activities compared with singular treatment. Combination treatment also markedly suppressed the protein expression levels of EGFR and mitogen-activated protein kinases (MAPKs) signaling (phosphorylation of ERK, JNK and p38). The results demonstrated that co-treatment with cetuximab and curcumin exerts synergistic oral anticancer effects on CAR cells through the suppression of the EGFR signaling by regulation of the MAPK pathway.

Curcuminoid Content and Safety-Related Markers of Quality of Turmeric Dietary Supplements Sold in an Urban Retail Marketplace in the United States

SCOPE

Turmeric is a top selling dietary supplement (DS) in the United States with rapidly expanding usage. Therefore, turmeric DS formulations available for sale in an urban US retail marketplace are analyzed, and point of sale information is related to measures of quality relevant to safety.

METHODS AND RESULTS

Eighty-seven unique turmeric DS are identified; a majority (94%) contained turmeric-derived curcuminoid extracts (TD-CE), which are combined with other bioactives in 47% of products, including piperine (24%), an additive that could alter the metabolism of concurrent medications. While curcuminoid content is within 80% of anticipated for a majority of products analyzed (n = 35), curcuminoid composition (% curcumin) did not meet US Pharmacopeia (USP) criteria for TD-CE in 59% and is suggestive of possible unlabeled use of synthetic curcumin in some. Lead content is associated with the inclusion of turmeric root and exceeded USP limits in one product. Residues of toxic class 1 or 2 solvents, which are not needed for TD-CE isolation, are present in 71% of products, although quantified levels were within USP-specified limits.

CONCLUSION

Assessment of turmeric DS quality at point of sale is difficult for consumers and may best be managed in partnership with knowledgeable healthcare professionals.

Micellar solubilisation enhances the antiinflammatory activities of curcumin and boswellic acids in rats with adjuvant-induced arthritis

OBJECTIVE

Native extracts of curcumin and boswellia are known to exert antiinflammatory properties but have poor bioavailability when given orally. Using advanced micellation technology, it has been possible to produce stable solubilisates of these extracts with markedly enhanced bioavailability. In the present study, we compared the chronic antiinflammatory activities of native and micellar curcumin in the rat adjuvant arthritis model, using diclofenac as a reference drug.

METHODS AND PROCEDURES

Adjuvant arthritis was induced by injecting Freund's complete adjuvant (FCA) into the right hind paw of rats and monitoring paw volume over 3 wk. The drugs were given daily for 3 wk, starting from the day of adjuvant inoculation. The serum was collected at end of the experiment for the assay of inflammatory and oxidative stress parameters. Statistical comparisons between different groups were carried out by one-way analysis of variance followed by Tukey-Kramer multiple comparison test.

RESULTS

Solubilized curcumin showed better antiinflammatory activity than its native form. The reduction in paw volume was reflected in corresponding changes in relevant mediators of inflammation like tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), myeloperoxidase (MPO), and lipid peroxidation markers. The combination of curcumin and boswellia solubilisates synergistically produced an even more potent therapeutic effect.

CONCLUSION

The findings confirm that micellar solubilisation of curcumin and boswellia not only increases their bioavailability, but also enhances their biological activity. Micellar curcumin, in particular in combination with micellar boswellia, may thus represent a promising concomitant tool for antiinflammatory treatment and a potential antiinflammatory alternative to synthetic drugs.

Effects of curcumin consumption on human chronic diseases: A narrative review of the most recent clinical data

Numerous clinical trials have investigated the potential beneficial effects of curcumin supplementation against several human chronic diseases. Up to now, it has been claimed that curcumin consumption may exert beneficial effects against several chronic diseases by promoting human health and preventing diseases. In this aspect, the present review aims to critically collect and in-depth summarize the most recent, well-designed clinical studies evaluating the potential beneficial effects of curcumin consumption on human health promotion and disease prevention. According to recent and well-designed clinical studies, curcumin consumption may benefit against obesity, metabolic syndrome, and diabetes. Moreover, curcumin consumption seems to exert a positive effect on people suffering from various types of cancer, fatty liver disease, depression, arthritis, skin diseases, gut inflammation, and symptoms of premenstrual syndrome. Due to the strong heterogeneity among the clinical studies concerning the exact effective curcumin dose and formulation, as well as the recommended treatment duration for each chronic disease, no precise and definitive conclusions could be drawn. Further large-scale prospective studies are strongly recommended, being well-designed as far as follow-up times, dosage, formulation, and duration of curcumin supplementation are concerned. Moreover, potential confounders in each specific chronic disease should carefully be taken into account in future studies.

Cellular effects of a turmeric root and rosemary leaf extract on canine neoplastic cell lines

BACKGROUND

The use of nutraceuticals is gaining in popularity in human and canine oncology with a relatively limited understanding of the effects in the vastly different tumor types seen in canine oncology. We have previously shown that turmeric root (TE) and rosemary leaf (RE) extracts can work synergistically to reduce neoplastic cell growth, but the mechanisms are poorly understood and require further elucidation.

RESULTS

Three different canine cell lines (C2 mastocytoma, and CMT-12 mammary carcinoma, D17 osteosarcoma) were treated with 6.3 μg mL^-1 extract individually, or 3.1 μg mL^-1 of each extract in combination based on studies showing synergy of these two extracts. Apoptosis, antioxidant effects, cellular accumulation of curcumin, and perturbation of signaling pathways were assessed. The TE + RE combination treatment resulted in Caspase 3/7 activation and apoptosis in all cell lines, beyond the effects of TE alone with the CMT-12 cell line being most susceptible. Both extracts had antioxidant effects with RE reducing reactive oxygen species (ROS) by 40-50% and TE reducing ROS by 80-90%. In addition RE treatment enhanced the c-jun N-terminal kinase (JNK) activity in the C2 cell line and TE + RE exposure increased activated JNK by 4-5 times in the CMT-12 cell line. Upon further examination, it was found that RE treatment caused a significant increase in the cellular accumulation of curcumin by approximately 30% in the C2 and D17 cell lines, and by 4.8-fold in the CMT-12 cell line. This increase in intracellular curcumin levels may play a role in the synergy exhibited when using TE and RE in combination.

CONCLUSIONS

The use of RE in combination with TE induces a synergistic response to induce apoptosis which is better than either extract alone. This appears to be related to a variable increased TE uptake in cells and activation of pathways involved in the apoptotic response.

The Holy Grail of Curcumin and its Efficacy in Various Diseases: Is Bioavailability Truly a Big Concern?

The powdered rhizome of turmeric has been extensively used in India and other South Asian cuisines, and is an integral part of Ayurvedic medicine for a broad range of conditions. In particular, curcumin, a major active component of turmeric, is one of the most studied botanicals for its anti-inflammatory, anti-oxidant and anti-cancer properties. Despite its well-documented therapeutic efficacy, for years the limited systemic bioavailability of curcumin has hindered its development as a potential therapeutic agent. However, recent introduction of unique extraction processes and various delivery methods has resulted in the development of new curcumin formulations and significantly improved its bioavailability. While these new formulations will no doubt expand curcumin's therapeutic potential, there are notable inconsistencies surrounding curcumin's bioavailability and corresponding bioactivity, raising some important questions. This article dissects various contributing factors of curcumin bioavailability to identify possible causes for the discrepancies associated with its bioactivity and discuss how these new curcumin formulations could further improve its clinical usefulness.

Effect of bis(hydroxymethyl) alkanoate curcuminoid derivative MTH-3 on cell cycle arrest, apoptotic and autophagic pathway in triple-negative breast adenocarcinoma MDA-MB-231 cells: An in vitro study

Curcumin has been shown to exert potential antitumor activity in vitro and in vivo involved in multiple signaling pathways. However, the application of curcumin is still limited because of its poor hydrophilicity and low bio-availability. In the present study, we investigated the therapeutic effects of a novel and water soluble bis(hydroxymethyl) alkanoate curcuminoid derivative, MTH-3, on human breast adenocarcinoma MDA-MB-231 cells. This study investigated the effect of MTH-3 on cell viability, cell cycle and induction of autophagy and apoptosis in MDA-MB-231 cells. After 24-h treatment with MTH-3, a concentration-dependent decrease in MDA-MB-231 cell viability was observed, and the IC₅₀ value was 5.37±1.22 μM. MTH-3 significantly triggered G₂/M phase arrest and apoptosis in MDA-MB-231 cells. Within a 24-h treatment, MTH-3 decreased the CDK1 activity by decreasing CDK1 and cyclin B1 protein levels. MTH-3-induced apoptosis was further confirmed by morphological assessment and Annexin V/PI staining assay. Induction of apoptosis caused by MTH-3 was accompanied by an apparent increase of DR3, DR5 and FADD and, as well as a marked decrease of Bcl-2 and Bcl-xL protein expression. MTH-3 also decreased the protein levels of Ero1, PDI, PERK and calnexin, as well as increased the expression of IRE1α, CHOP and Bip that consequently led to ER stress and MDA-MB-231 cell apoptosis. In addition, MTH-3-treated cells were involved in the autophagic process and cleavage of LC3B was observed. MTH-3 enhanced the protein levels of LC3B, Atg5, Atg7, Atg12, p62 and Beclin-1 in MDA-MB-231 cells. Finally, DNA microarray was carried out to investigate the level changes of gene expression modulated by MTH-3 in MDA-MB-231 cells. Taken together, our results suggest that MTH-3 might be a novel therapeutic agent for the treatment of triple-negative breast cancer in the near future.

A Comparative Pharmacokinetic Assessment of a Novel Highly Bioavailable Curcumin Formulation with 95% Curcumin: A Randomized, Double-Blind, Crossover Study

OBJECTIVE

Curcumin exhibits many beneficial health-promoting characteristics. However, its poor oral absorption precludes its general use. This study assessed the bioavailability of a novel curcumin formulation compared to 95% curcumin and published results for various other curcumin formulations.

METHODS

A randomized, crossover, double-blind, comparator-controlled pharmacokinetic study was performed in 12 healthy adult subjects to determine the appearance of free curcumin and its metabolites curcumin sulfate and curcumin glucuronide in plasma after a single dose of a novel proprietary curcumin liquid droplet micromicellar formulation (CLDM) and unformulated 95% curcumin powder in capsule form. An equivalent 400-mg dose of each product was administered. The 95% curcumin contained 323 mg curcumin, and the CLDM contained 64.6 mg curcumin. Blood samples were drawn and plasma was analyzed for curcumin and its 2 conjugates without enzymatic hydrolysis by liquid chromatography-tandem mass spectroscopy.

RESULTS

Plasma levels of curcumin sulfate and curcumin glucuronide after 1.5 hours from CLDM were approximately 20 and 300 ng/mL, respectively, whereas the levels for 95% curcumin were near baseline. Free curcumin reached a maximum level of 2 ng/mL for CLDM and 0.3 ng/mL for 95% curcumin at 1.5 hours. For the CLDM, a small secondary free curcumin peak occurred at 12 hours and a tertiary 1.5-ng/mL peak occurred at 24 hours. The total curcumin absorbed as represented by the area under the curve (AUC)/mg administered curcumin for CLDM was 522 times greater than for the 95% curcumin.

CONCLUSIONS

The novel CLDM formulation facilitates absorption and produces exceedingly high plasma levels of both conjugated and total curcumin compared to 95% curcumin. A comparison of the C_max/mg curcumin and AUC/mg of administered curcumin for CLDM with data from pharmacokinetic studies of various enhanced absorption formulations indicate that the greatest absorption and bioavailability are produced with the novel CLDM formulation.

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

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

Multifunctional Nanotube-Mucoadhesive Poly(methyl vinyl ether-co-maleic acid)@Hydroxypropyl Methylcellulose Acetate Succinate Composite for Site-Specific Oral Drug Delivery

An advanced oral drug delivery system that can effectively deliver drugs with poor oral bioavailability is strongly desirable. Herein, a multifunctional nano-in-micro structured composite is developed by encapsulation of the mucoadhesive poly(methyl vinyl ether-co-maleic acid) modified halloysite nanotubes (HNTs) with the pH-responsive hydroxypropyl methylcellulose acetate succinate by the microfluidics to control the drug release, increase cell-particle interaction, and improve drug absorption. The microparticles show spherical shape, homogeneous particle size distribution (58 ± 1 µm), and pH-responsive dissolution behavior at pH > 6, and they prevent the premature release of curcumin in simulated pH conditions of the stomach and immediately release the curcumin in simulated pH conditions of the small intestine. The surface modification of HNT with mucoadhesive poly(methyl vinyl ether-co-maleic acid) significantly enhances its interactions with the intestinal Caco-2/HT29-MTX cells and the mouse small intestines, and increases the permeability of curcumin across the co-cultured Caco-2/HT29-MTX cell monolayers by about 13 times compared to the free curcumin. Therefore, the developed multifunctional nanotube-mucoadhesive poly(methyl vinyl ether-co-maleic acid)@hydroxypropyl methylcellulose acetate succinate composite is a promising oral drug delivery system for drugs with poor oral bioavailability.

Comparison of remicade to curcumin for the treatment of Crohn's disease: A systematic review

OBJECTIVE

The aim of this study was to review the literature to assess if there is evidence to support the use of Curcumin as a safe complementary therapy in treating Crohn's Disease (CD) in conjunction with Remicade.

DESIGN

Systematic searches were performed by three researchers using electronic databases (ProQuest Medical Library, CINAHL Complete, and PUBMED) to locate and identify articles to meet a predetermined set of inclusion criteria. Specifically full text, peer-reviewed articles published after 2007 were included if they studied human participants 18 years or older.

RESULTS

Tumor necrosis factor-alpha (TNF-a) and Interleukin-1 (IL-1) levels increase in CD patients. Remicade reduces TNF-a in adults with CD. The issues are eventual loss of response (LOR) once IL-1 increases, and severe risks such as malignancy. CD patients using Curcumin saw a 55 point mean reduction in the Crohn's Disease Activity Index, reducing IL-1 and Crp. Plus it reduced TNF-a and PPMTase which improved colorectal cancer outcomes.

CONCLUSIONS

LOR of Remicade occurs when IL-1 increases, and it can cause malignancy. Research shows Curcumin reduces IL-1 and improves cancer outcomes. Future research, using both Remicade and Curcumin, would have to be done, but preliminary data would suggest using both would reduce LOR. Curcumin, even by itself, was found to be a cheap and safe way to reduce CD symptoms and inflammatory markers.

New bis(hydroxymethyl) alkanoate curcuminoid derivatives exhibit activity against triple-negative breast cancer in vitro and in vivo

Novel bis(hydroxymethyl) alkanoate curcuminoid derivatives were designed, synthesized and screened for in vitro antiproliferative and in vivo antitumor activity. Selected new compound 9a and curcumin were further evaluated for inhibitory activity against ER⁺/PR⁺ breast cancer (MCF-7, T47D), HER 2⁺ breast cancer (SKBR3, BT474, and MDA-MB-457) and triple negative breast cancer (TNBC) (HS-578T, MDA-MB-157, and MDA-MB-468) cell lines. In addition, compound 9a was evaluated in the MDA-MB-231 xenograft nude mice model. Compound 9a exhibited greater inhibitory activity than curcumin against TNBC cells and also demonstrated significant inhibitory activity against doxorubicin-resistant MDA-MB-231 cells, with ten-fold higher potency than curcumin. Furthermore, when evaluated against the MDA-MB-231 xenograft nude mice model, compound 9a alone was ten-fold more potent than curcumin. Moreover, synergistic activity was observed when 9a was used in combination with doxorubicin against MDA-MB-231 breast cancer cells.

Curcumin improves intestinal barrier function: modulation of intracellular signaling, and organization of tight junctions

Association between circulating lipopolysaccharide (LPS) and metabolic diseases (such as type 2 diabetes and atherosclerosis) has shifted the focus from high-fat high-cholesterol containing Western-type diet (WD)-induced changes in gut microbiota per se to release of gut bacteria-derived products (e.g., LPS) into circulation due to intestinal barrier dysfunction as the possible mechanism for the chronic inflammatory state underlying the development of these diseases. We demonstrated earlier that oral supplementation with curcumin attenuates WD-induced development of type 2 diabetes and atherosclerosis. Poor bioavailability of curcumin has precluded the establishment of a causal relationship between oral supplementation and it is in vivo effects. We hypothesized that curcumin attenuates WD-induced chronic inflammation and associated metabolic diseases by modulating the function of intestinal epithelial cells (IECs) and the intestinal barrier function. The objective of the present study was to delineate the underlying mechanisms. The human IEC lines Caco-2 and HT-29 were used for these studies and modulation of direct as well as indirect effects of LPS on intracellular signaling as well as tight junctions were examined. Pretreatment with curcumin significantly attenuated LPS-induced secretion of master cytokine IL-1β from IECs and macrophages. Furthermore, curcumin also reduced IL-1β-induced activation of p38 MAPK in IECs and subsequent increase in expression of myosin light chain kinase involved in the phosphorylation of tight junction proteins and ensuing disruption of their normal arrangement. The major site of action of curcumin is, therefore, likely the IECs and the intestinal barrier, and by reducing intestinal barrier dysfunction, curcumin modulates chronic inflammatory diseases despite poor bioavailability.

TBI-induced nociceptive sensitization is regulated by histone acetylation

Chronic pain after traumatic brain injury (TBI) is very common, but the mechanisms linking TBI to pain and the pain-related interactions of TBI with peripheral injuries are poorly understood. In these studies we pursued the hypothesis that TBI pain sensitization is associated with histone acetylation in the rat lateral fluid percussion model. Some animals received hindpaw incisions in addition to TBI to mimic polytrauma. Neuropathological analysis of brain tissue from sham and TBI animals revealed evidence of bleeding, breakdown of the blood brain barrier, in the cortex, hippocampus, thalamus and other structures related to pain signal processing. Mechanical allodynia was measured in these animals for up to eight weeks post-injury. Inhibitors of histone acetyltransferase (HAT) and histone deacetylase (HDAC) were used to probe the role of histone acetylation in such pain processing. We followed serum markers including glial fibrillary acidic protein (GFAP), neuron-specific enolase 2 (NSE) myelin basic protein (MBP) and S100β to gauge TBI injury severity. Our results showed that TBI caused mechanical allodynia in the hindpaws of the rats lasting several weeks. Hindpaws contralateral to TBI showed more rapid and profound sensitization than ipsilateral hindpaws. The inhibition of HAT using curcumin 50 mg/kg s.c reduced mechanical sensitization while the HDAC inhibitor suberoylanilide hydroxamic acid 50 mg/kg i.p. prolonged sensitization in the TBI rats. Immunohistochemical analyses of spinal cord tissue localized changes in the level of acetylation of the H3K9 histone mark to dorsal horn neurons. Taken together, these findings demonstrate that TBI induces sustained nociceptive sensitization, and changes in spinal neuronal histone proteins may play an important role.

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Pain after traumatic brain injury (TBI) is common and often persistent.

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Using the rat lateral fluid percussion model, it was observed that hindpaw allodynia is present for three weeks after TBI.

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Damage to pain processing areas of the brain can be demonstrated after TBI.

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Agents regulating the epigenetic acetylation of histone proteins modified the time course of TBI-induced allodynia.

Curcumin and Resveratrol as Promising Natural Remedies with Nanomedicine Approach for the Effective Treatment of Triple Negative Breast Cancer

Researchers have made considerable progress in last few decades in understanding mechanisms underlying pathogenesis of breast cancer, its phenotypes, its molecular and genetic changes, its physiology, and its prognosis. This has allowed us to identify specific targets and design appropriate chemical entities for effective treatment of most breast cancer phenotypes, resulting in increased patient survivability. Unfortunately, these strategies have been largely ineffective in the treatment of triple negative breast cancer (TNBC). Hormonal receptors lacking render the conventional breast cancer drugs redundant, forcing scientists to identify novel targets for treatment of TNBC. Two natural compounds, curcumin and resveratrol, have been widely reported to have anticancer properties. In vitro and in vivo studies show promising results, though their effectiveness in clinical settings has been less than satisfactory, owing to their feeble pharmacokinetics. Here we discuss these naturally occurring compounds, their mechanism as anticancer agents, their shortcomings in translational research, and possible methodology to improve their pharmacokinetics/pharmacodynamics with advanced drug delivery systems.