Showing papers on "Curcumin published in 2008"
TL;DR: Curcumin, a spice once relegated to the kitchen shelf, has moved into the clinic and may prove to be "Curecumin", a therapeutic agent in wound healing, diabetes, Alzheimer disease, Parkinson disease, cardiovascular disease, pulmonary disease, and arthritis.
1,897 citations
TL;DR: Curcumin exhibits great promise as a therapeutic agent, and is currently in human clinical trials for a variety of conditions, including multiple myeloma, pancreatic cancer, myelodysplastic syndromes, colon cancer, psoriasis and Alzheimer’s disease.
Abstract: Curcumin is the active ingredient in the traditional herbal remedy and dietary spice turmeric (Curcuma longa). Curcumin has a surprisingly wide range of beneficial properties, including anti-inflammatory, antioxidant, chemopreventive and chemotherapeutic activity. The pleiotropic activities of curcumin derive from its complex chemistry as well as its ability to influence multiple signaling pathways, including survival pathways such as those regulated by NF-κB, Akt, and growth factors; cytoprotective pathways dependent on Nrf2; and metastatic and angiogenic pathways. Curcumin is a free radical scavenger and hydrogen donor, and exhibits both pro- and antioxidant activity. It also binds metals, particularly iron and copper, and can function as an iron chelator. Curcumin is remarkably non-toxic and exhibits limited bioavailability. Curcumin exhibits great promise as a therapeutic agent, and is currently in human clinical trials for a variety of conditions, including multiple myeloma, pancreatic cancer, myelodysplastic syndromes, colon cancer, psoriasis and Alzheimer’s disease.
1,599 citations
TL;DR: Oral curcumin is well tolerated and, despite its limited absorption, has biological activity in some patients with pancreatic cancer.
Abstract: Purpose: Pancreatic cancer is almost always lethal, and the only U.S. Food and Drug Administration–approved therapies for it, gemcitabine and erlotinib, produce objective responses in Experimental Design: Patients received 8 g curcumin by mouth daily until disease progression, with restaging every 2 months. Serum cytokine levels for interleukin (IL)-6, IL-8, IL-10, and IL-1 receptor antagonists and peripheral blood mononuclear cell expression of NF-κB and cyclooxygenase-2 were monitored. Results: Twenty-five patients were enrolled, with 21 evaluable for response. Circulating curcumin was detectable as drug in glucuronide and sulfate conjugate forms, albeit at low steady-state levels, suggesting poor oral bioavailability. Two patients showed clinical biological activity. One had ongoing stable disease for >18 months; interestingly, one additional patient had a brief, but marked, tumor regression (73%) accompanied by significant increases (4- to 35-fold) in serum cytokine levels (IL-6, IL-8, IL-10, and IL-1 receptor antagonists). No toxicities were observed. Curcumin down-regulated expression of NF-κB, cyclooxygenase-2, and phosphorylated signal transducer and activator of transcription 3 in peripheral blood mononuclear cells from patients (most of whom had baseline levels considerably higher than those found in healthy volunteers). Whereas there was considerable interpatient variation in plasma curcumin levels, drug levels peaked at 22 to 41 ng/mL and remained relatively constant over the first 4 weeks. Conclusions: Oral curcumin is well tolerated and, despite its limited absorption, has biological activity in some patients with pancreatic cancer.
1,173 citations
TL;DR: This review focuses on the status of all these approaches in generating a "super curcumin," a homodimer of feruloylmethane containing a methoxy group and a hydroxyl group, a heptadiene with two Michael acceptors, and an alpha,beta-diketone.
1,095 citations
TL;DR: The activity of curcumin reported against leukemia and lymphoma, gastrointestinal cancers, genitourinary cancers, breast cancer, ovarian cancer, head and neck squamous cell carcinoma, lung cancer, melanoma, neurological cancers, and sarcoma reflects its ability to affect multiple targets.
1,014 citations
TL;DR: Curcumin has been found to inhibit the proliferation of various tumor cells in culture, prevents carcinogen-induced cancers in rodents, and inhibits the growth of human tumors in xenotransplant or orthOTransplant animal models either alone or in combination with chemotherapeutic agents or radiation.
1,006 citations
TL;DR: An overview of the extensive published literature on the use of curcumin as a therapy for malignant and inflammatory diseases and its potential use in the treatment of degenerative neurologic diseases, cystic fibrosis, and cardiovascular diseases is provided.
Abstract: Curcumin is a natural polyphenol used in ancient Asian medicine. Since the first article referring to the use of curcumin to treat human disease was published in The Lancet in 1937, >2,600 research studies using curcumin or turmeric have been published in English language journals. The mechanisms implicated in the inhibition of tumorigenesis by curcumin are diverse and appear to involve a combination of antiinflammatory, antioxidant, immunomodulatory, proapoptotic, and antiangiogenic properties via pleiotropic effects on genes and cell-signaling pathways at multiple levels. The potentially adverse sequelae of curcumin's effects on proapoptotic genes, particularly p53, represent a cause for current debate. When curcumin is combined with some cytotoxic drugs or certain other diet-derived polyphenols, synergistic effects have been demonstrated. Although curcumin's low systemic bioavailability after oral dosing may limit access of sufficient concentrations for pharmacologic effects in tissues outside the gastrointestinal tract, chemical analogues and novel delivery methods are in preclinical development to overcome this barrier. This article provides an overview of the extensive published literature on the use of curcumin as a therapy for malignant and inflammatory diseases and its potential use in the treatment of degenerative neurologic diseases, cystic fibrosis, and cardiovascular diseases. Despite the breadth of the coverage, particular emphasis is placed on the prevention and treatment of human cancers.
592 citations
TL;DR: Data indicate that the dienone bridge present in curcumin, but not in TC, is necessary to reduce plaque deposition and protein oxidation in an Alzheimer's model, and should help translation efforts from multiple successful preclinical models.
Abstract: Curcumin can reduce inflammation and neurodegeneration, but its chemical instability and metabolism raise concerns, including whether the more stable metabolite tetrahydrocurcumin (TC) may mediate efficacy. We examined the antioxidant, anti-inflammatory, or anti-amyloidogenic effects of dietary curcumin and TC, either administered chronically to aged Tg2576 APPsw mice or acutely to lipopolysaccharide (LPS)-injected wild-type mice. Despite dramatically higher drug plasma levels after TC compared with curcumin gavage, resulting brain levels of parent compounds were similar, correlating with reduction in LPS-stimulated inducible nitric-oxide synthase, nitrotyrosine, F2 isoprostanes, and carbonyls. In both the acute (LPS) and chronic inflammation (Tg2576), TC and curcumin similarly reduced interleukin-1beta. Despite these similarities, only curcumin was effective in reducing amyloid plaque burden, insoluble beta-amyloid peptide (Abeta), and carbonyls. TC had no impact on plaques or insoluble Abeta, but both reduced Tris-buffered saline-soluble Abeta and phospho-c-Jun NH(2)-terminal kinase (JNK). Curcumin but not TC prevented Abeta aggregation. The TC metabolite was detected in brain and plasma from mice chronically fed the parent compound. These data indicate that the dienone bridge present in curcumin, but not in TC, is necessary to reduce plaque deposition and protein oxidation in an Alzheimer's model. Nevertheless, TC did reduce neuroinflammation and soluble Abeta, effects that may be attributable to limiting JNK-mediated transcription. Because of its favorable safety profile and the involvement of misfolded proteins, oxidative damage, and inflammation in multiple chronic degenerative diseases, these data relating curcumin dosing to the blood and tissue levels required for efficacy should help translation efforts from multiple successful preclinical models.
559 citations
TL;DR: Fluorescence quenching showed that curcumin molecules quench the intrinsic fluorescence of caseins upon binding, and the utility of CMs as carriers ofCurcumin was evaluated by using in vitro cultured HeLa cells.
491 citations
TL;DR: Curcumin is a polyphenolic molecule that comprises approximately 5% of turmeric, giving the spice its color but not flavor, and is used in processed foods as a yellow coloring.
Abstract: To the Editors:Curcumin is a polyphenolic molecule that comprises approximately 5% of turmeric, giving the spice its color but not flavor. It is used in processed foods as a yellow coloring. 1 Because of its anti-inflammatory and antioxidant properties, curcumin has been tested in animal models of A
491 citations
TL;DR: Due to various effects of curcumin, such as decreased Beta-amyloid plaques, delayed degradation of neurons, metal-chelation, anti-inflammatory, antioxidant and decreased microglia formation, the overall memory in patients with AD has improved.
Abstract: This paper discusses the effects of curcumin on patients with Alzheimer's disease (AD). Curcumin (Turmeric), an ancient Indian herb used in curry powder, has been extensively studied in modern medicine and Indian systems of medicine for the treatment of various medical conditions, including cystic fibrosis, haemorrhoids, gastric ulcer, colon cancer, breast cancer, atherosclerosis, liver diseases and arthritis. It has been used in various types of treatments for dementia and traumatic brain injury. Curcumin also has a potential role in the prevention and treatment of AD. Curcumin as an antioxidant, anti-inflammatory and lipophilic action improves the cognitive functions in patients with AD. A growing body of evidence indicates that oxidative stress, free radicals, beta amyloid, cerebral deregulation caused by bio-metal toxicity and abnormal inflammatory reactions contribute to the key event in Alzheimer's disease pathology. Due to various effects of curcumin, such as decreased Beta-amyloid plaques, delayed degradation of neurons, metal-chelation, anti-inflammatory, antioxidant and decreased microglia formation, the overall memory in patients with AD has improved. This paper reviews the various mechanisms of actions of curcumin in AD and pathology.
TL;DR: Curcumin is absorbed after oral dosing in humans and can be detected as glucuronide and sulfate conjugates in plasma.
Abstract: Background: Curcumin is a polyphenol, found in the spice turmeric, that has promising anticancer properties, but previous studies suggest that absorption of curcumin may be limited.
Methods: This study examined the pharmacokinetics of a curcumin preparation in healthy human volunteers 0.25 to 72 h after a single oral dose. Curcumin was administered at doses of 10 g ( n = 6) and 12 g ( n = 6). Subjects were randomly allocated to dose level for a total of six subjects at each dose level. Serum samples were assayed for free curcumin, for its glucuronide, and for its sulfate conjugate. The data were fit to a one-compartment absorption and elimination model.
Results: Using a high-performance liquid chromatography assay with a limit of detection of 50 ng/mL, only one subject had detectable free curcumin at any of the 14 time points assayed, but curcumin glucuronides and sulfates were detected in all subjects. Based on the pharmacokinetic model, the area under the curve for the 10 and 12 g doses was estimated (mean ± SE) to be 35.33 ± 3.78 and 26.57 ± 2.97 μg/mL × h, respectively, whereas C max was 2.30 ± 0.26 and 1.73 ± 0.19 μg/mL. The T max and t 1/2 were estimated to be 3.29 ± 0.43 and 6.77 ± 0.83 h. The ratio of glucuronide to sulfate was 1.92:1. The curcumin conjugates were present as either glucuronide or sulfate, not mixed conjugates.
Conclusion: Curcumin is absorbed after oral dosing in humans and can be detected as glucuronide and sulfate conjugates in plasma. (Cancer Epidemiol Biomarkers Prev 2008;17(6):1411–7)
TL;DR: There is a 43% or 85% inhibition effect of 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced edema of mouse ear for 618.6nm and 79.5nm 1% curcumin O/W emulsions, respectively, but a negligible effect is found for 1%Curcumin in 10% Tween 20 water solution.
TL;DR: It is concluded that orally ingested curcumin reverses many of the inflammatory and metabolic derangements associated with obesity and improves glycemic control in mouse models of type 2 diabetes.
Abstract: Obesity is a major risk factor for the development of type 2 diabetes, and both conditions are now recognized to possess significant inflammatory components underlying their pathophysiologies. We tested the hypothesis that the plant polyphenolic compound curcumin, which is known to exert potent antiinflammatory and antioxidant effects, would ameliorate diabetes and inflammation in murine models of insulin-resistant obesity. We found that dietary curcumin admixture ameliorated diabetes in high-fat diet-induced obese and leptin-deficient ob/ob male C57BL/6J mice as determined by glucose and insulin tolerance testing and hemoglobin A1c percentages. Curcumin treatment also significantly reduced macrophage infiltration of white adipose tissue, increased adipose tissue adiponectin production, and decreased hepatic nuclear factor-kappaB activity, hepatomegaly, and markers of hepatic inflammation. We therefore conclude that orally ingested curcumin reverses many of the inflammatory and metabolic derangements associated with obesity and improves glycemic control in mouse models of type 2 diabetes. This or related compounds warrant further investigation as novel adjunctive therapies for type 2 diabetes in man.
TL;DR: Curcumin protects the rat liver from CCl4-caused injury and fibrogenesis by suppressing hepatic inflammation, attenuating hepatic oxidative stress and inhibiting HSC activation, and suggesting that curcumin might be a therapeutic antifibrotic agent for the treatment of hepatic fibrosis.
Abstract: We previously demonstrated that curcumin, a polyphenolic antioxidant purified from turmeric, up-regulated peroxisome proliferator-activated receptor (PPAR)-gamma gene expression and stimulated its signaling, leading to the inhibition of activation of hepatic stellate cells (HSC) in vitro. The current study evaluates the in vivo role of curcumin in protecting the liver against injury and fibrogenesis caused by carbon tetrachloride (CCl(4)) in rats and further explores the underlying mechanisms. We hypothesize that curcumin might protect the liver from CCl(4)-caused injury and fibrogenesis by attenuating oxidative stress, suppressing inflammation, and inhibiting activation of HSC. This report demonstrates that curcumin significantly protects the liver from injury by reducing the activities of serum aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase, and by improving the histological architecture of the liver. In addition, curcumin attenuates oxidative stress by increasing the content of hepatic glutathione, leading to the reduction in the level of lipid hydroperoxide. Curcumin dramatically suppresses inflammation by reducing levels of inflammatory cytokines, including interferon-gamma, tumor necrosis factor-alpha, and interleukin-6. Furthermore, curcumin inhibits HSC activation by elevating the level of PPARgamma and reducing the abundance of platelet-derived growth factor, transforming growth factor-beta, their receptors, and type I collagen. This study demonstrates that curcumin protects the rat liver from CCl(4)-caused injury and fibrogenesis by suppressing hepatic inflammation, attenuating hepatic oxidative stress and inhibiting HSC activation. These results confirm and extend our prior in vitro observations and provide novel insights into the mechanisms of curcumin in the protection of the liver. Our results suggest that curcumin might be a therapeutic antifibrotic agent for the treatment of hepatic fibrosis.
TL;DR: It is concluded that inhibition of p300 HAT activity by the nontoxic dietary compound curcumin may provide a novel therapeutic strategy for heart failure in humans.
Abstract: Hemodynamic overload in the heart can trigger maladaptive hypertrophy of cardiomyocytes. A key signaling event in this process is nuclear acetylation by histone deacetylases and p300, an intrinsic histone acetyltransferase (HAT). It has been previously shown that curcumin, a polyphenol responsible for the yellow color of the spice turmeric, possesses HAT inhibitory activity with specificity for the p300/CREB-binding protein. We found that curcumin inhibited the hypertrophy-induced acetylation and DNA-binding abilities of GATA4, a hypertrophy-responsive transcription factor, in rat cardiomyocytes. Curcumin also disrupted the p300/GATA4 complex and repressed agonist- and p300-induced hypertrophic responses in these cells. Both the acetylated form of GATA4 and the relative levels of the p300/GATA4 complex markedly increased in rat hypertensive hearts in vivo. The effects of curcumin were examined in vivo in 2 different heart failure models: hypertensive heart disease in salt-sensitive Dahl rats and surgically induced myocardial infarction in rats. In both models, curcumin prevented deterioration of systolic function and heart failure-induced increases in both myocardial wall thickness and diameter. From these results, we conclude that inhibition of p300 HAT activity by the nontoxic dietary compound curcumin may provide a novel therapeutic strategy for heart failure in humans.
TL;DR: Observations suggest that modulation of miRNA expression may be an important mechanism underlying the biological effects of curcumin.
Abstract: Background: A major challenge in cancer chemotherapy has been developing safe and clinically efficacious chemotherapeutic agents. With its low toxicity profile, curcumin (diferuloylmethane), a naturally occurring flavinoid derived from the rhizome of Curcuma longa , has great promise. In vitro and in vivo preclinical studies have shown its inhibitory anticancer, antioxidant, anti-inflammatory, antiproliferative, and proapoptotic activities. The multiple mechanisms of the antitumor effect of curcumin putatively include down-regulating the expression of gene products such as nuclear factor-κB, growth suppression, inducing apoptosis, and modulating various signal transduction pathways and the expression of many oncogenes. The mechanisms underlying the antitumor activity of curcumin have not, however, been completely delineated. Methods: An oligonucleotide microarray chip was developed and used to profile microRNA (miRNA) expressions in pancreatic cells treated with curcumin. Transcripts with regulated expression patterns on the arrays were validated by real-time PCRs. Additionally, potential mRNA targets were analyzed bioinformatically and confirmed with flow cytometry experiments. Results: Curcumin alters miRNA expression in human pancreatic cells, up-regulating miRNA-22 and down-regulating miRNA-199a*, as confirmed by TaqMan real-time PCR. Upregulation of miRNA-22 expression by curcumin or by transfection with miRNA-22 mimetics in the PxBC-3 pancreatic cancer cell line suppressed expression of its target genes SP1 transcription factor (SP1) and estrogen receptor 1 (ESR1) , while inhibiting miRNA-22 with antisense enhanced SP1 and ESR1 expression. Conclusions: These observations suggest that modulation of miRNA expression may be an important mechanism underlying the biological effects of curcumin. [Mol Cancer Ther 2008;7(3):464–73]
TL;DR: In vitro and in vivo cancer-related activities of curcumin are analyzed and it is discussed that they are linked to its known antioxidant and pro-oxidant properties and several considerations that may help developCurcumin as an anticancer agent are discussed.
Abstract: A growing body of research suggests that curcumin, the major active constituent of the dietary spice turmeric, has potential for the prevention and therapy of cancer. Preclinical data have shown that curcumin can both inhibit the formation of tumors in animal models of carcinogenesis and act on a variety of molecular targets involved in cancer development. In vitro studies have demonstrated that curcumin is an efficient inducer of apoptosis and some degree of selectivity for cancer cells has been observed. Clinical trials have revealed that curcumin is well tolerated and may produce antitumor effects in people with precancerous lesions or who are at a high risk for developing cancer. This seems to indicate that curcumin is a pharmacologically safe agent that may be used in cancer chemoprevention and therapy. Both in vitro and in vivo studies have shown, however, that curcumin may produce toxic and carcinogenic effects under specific conditions. Curcumin may also alter the effectiveness of radiotherapy and chemotherapy. This review article analyzes the in vitro and in vivo cancer-related activities of curcumin and discusses that they are linked to its known antioxidant and pro-oxidant properties. Several considerations that may help develop curcumin as an anticancer agent are also discussed.
TL;DR: It is suggested that curcumin can stimulate developmental and adult hippocampal neurogenesis, and a biological activity that may enhance neural plasticity and repair is suggested.
TL;DR: The main effects ofCurcumin on the different apoptotic signaling pathways involved in curcumin-induced apoptosis of cancer cells, including the intrinsic and extrinsic apoptosis pathways, the NF-kappaB-mediated pathway as well as the PI3K/Akt signaling pathway are reviewed.
TL;DR: Cytotoxicity studies in different cell lines indicated that the toxicity of curcumin increased with increasing uptake, and sub-cellular fractionation of curCumin-loaded MCF7 cells supported the differential distribution ofCurcumin in membrane, cytoplasm and nuclear compartments of cell with maximum localization in the membrane.
TL;DR: Curcumin attenuates PAO1 virulence by down-regulation of virulence factors, QS, and biofilm initiation genes, which makes curcumin a potential supplemental molecule for the treatment of P. aeruginosa infections.
Abstract: The effect of curcumin on the virulence of Pseudomonas aeruginosa (PAO1) using whole plant and animal pathogenicity models was investigated. The effect of curcumin on PAO1 virulence was studied by employing in vitro assays for virulence factor production, Arabidopsis thaliana/Caenorhabditis elegans pathogenicity models, and whole genome microarray analysis. It is shown that the curcumin inhibits PAO1 virulence factors such as biofilm formation, pyocyanin biosynthesis, elastase/protease activity, and acyl homoserine lactone (HSL) production. As a consequence of this, curcumin treatment resulted in the reduced pathogenicity of P. aeruginosa-C. elegans and P. aeruginosa-A. thaliana infection models. In addition, transcriptome analysis of curcumin-treated PAO1 revealed down-regulation of 31 quorum sensing (QS) genes, of which many have already been reported for virulence. The supplementation of HSLs along with the curcumin treatment resulted in increased pathogencity and recovery of higher bacterial titers in a plant pathogenecity model. These data reveal the involvement of curcumin in QS interruption to reduce pathogenicity. Curcumin attenuates PAO1 virulence by down-regulation of virulence factors, QS, and biofilm initiation genes. The effect of curcumin on multiple targets such as virulence, QS, and biofilm initiation makes curcumin a potential supplemental molecule for the treatment of P. aeruginosa infections.
TL;DR: The coadministration of curcumin along with piperine may prove to be a useful and potent natural antidepressant approach in the management of depression.
Abstract: Rationale
Curcumin is a major active principle of Curcuma longa, one of the widely used preparations in the Indian system of medicine. It is known for its diverse biological actions.
TL;DR: Oral administration of curcumin at 200mg/kg dose for four consecutive days not only protected against dimethylnitrosamine (DMN)-induced hepatic injury, but also resulted in more than three-fold induction of HO-1 protein expression as well as activity in rat liver.
TL;DR: Reconstituting curcumin with the non-curcuminoid components of turmeric has been found to increase the bioavailability substantially and BCM-95®CG, a patented formulation, has potential for widespread application for various chronic diseases.
Abstract: Curcumin, the bioactive component of turmeric, Curcuma longa has an exceptionally wide spectrum of activities including antioxidant, anti-inflammatory and anti-cancer properties, and is currently under different phases of clinical trials for various types of soft tissue cancers. However, although in vitro and animal studies have shown anticancer activities of curcumin for virtually all types of human cancers, its poor bioavailability in the human body has severely limited its application to these diseases. Methods to increase its oral bioavailability are a subject of intense current research. Reconstituting curcumin with the non-curcuminoid components of turmeric has been found to increase the bioavailability substantially. In the present clinical study to determine the bioavailability of curcuminoids, a patented formulation, BCM-95((R))CG was tested on human volunteer group. Normal curcumin was used in the control group. Curcumin content in blood was estimated at periodical intervals. After a washout period of two weeks the control group and drug group were crossed over BCM-95((R))CG and curcumin, respectively. It was also compared with a combination of curcumin-lecithin-piperine which was earlier shown to provide enhanced bioavailability. The results of the study indicate that the relative bioavailability of BCM-95((R))CG (Biocurcumax) was about 6.93-fold compared to normal curcumin and about 6.3-fold compared to curcumin-lecithin-piperine formula. BCM-95((R))CG thus, has potential for widespread application for various chronic diseases.
TL;DR: Based on its ability to inhibit the proteasome and induce apoptosis in both HCT-116 and metastatic SW480 colon cancer cell lines, this study suggests that curcumin could potentially be used for treatment of both early-stage and late-stage/refractory colon cancer.
Abstract: Curcumin (diferuloylmethane) is the major active ingredient of turmeric (Curcuma longa) used in South Asian cuisine for centuries. Curcumin has been shown to inhibit the growth of transformed cells and to have a number of potential molecular targets. However, the essential molecular targets of curcumin under physiologic conditions have not been completely defined. Herein, we report that the tumor cellular proteasome is most likely an important target of curcumin. Nucleophilic susceptibility and in silico docking studies show that both carbonyl carbons of the curcumin molecule are highly susceptible to a nucleophilic attack by the hydroxyl group of the NH(2)-terminal threonine of the proteasomal chymotrypsin-like (CT-like) subunit. Consistently, curcumin potently inhibits the CT-like activity of a purified rabbit 20S proteasome (IC(50) = 1.85 micromol/L) and cellular 26S proteasome. Furthermore, inhibition of proteasome activity by curcumin in human colon cancer HCT-116 and SW480 cell lines leads to accumulation of ubiquitinated proteins and several proteasome target proteins, and subsequent induction of apoptosis. Furthermore, treatment of HCT-116 colon tumor-bearing ICR SCID mice with curcumin resulted in decreased tumor growth, associated with proteasome inhibition, proliferation suppression, and apoptosis induction in tumor tissues. Our study shows that proteasome inhibition could be one of the mechanisms for the chemopreventive and/or therapeutic roles of curcumin in human colon cancer. Based on its ability to inhibit the proteasome and induce apoptosis in both HCT-116 and metastatic SW480 colon cancer cell lines, our study suggests that curcumin could potentially be used for treatment of both early-stage and late-stage/refractory colon cancer.
TL;DR: Curcumin regulates multiple targets (multitargeted therapy), which is needed for treatment of most diseases, and it is inexpensive and has been found to be safe in human clinical trials.
Abstract: Although traditional medicines have been used for thousands of years, for most such medicines neither the active component nor their molecular targets have been very well identified. Curcumin, a yellow component of turmeric or curry powder, however, is an exception. Although inhibitors of cyclooxygenase-2, HER2, tumor necrosis factor, EGFR, Bcr-abl, proteosome, and vascular endothelial cell growth factor have been approved for human use by the United States Food and Drug Administration (FDA), curcumin as a single agent can down-regulate all these targets. Curcumin can also activate apoptosis, down-regulate cell survival gene products, and up-regulate p53, p21, and p27. Although curcumin is poorly absorbed after ingestion, multiple studies have suggested that even low levels of physiologically achievable concentrations of curcumin may be sufficient for its chemopreventive and chemotherapeutic activity. Thus, curcumin regulates multiple targets (multitargeted therapy), which is needed for treatment of most diseases, and it is inexpensive and has been found to be safe in human clinical trials. The present article reviews the key molecular mechanisms of curcumin action and compares this to some of the single-targeted therapies currently available for human cancer.
TL;DR: The data suggest that curcumin inhibits AS oligomerization into higher molecular weight aggregates and therefore should be further explored as a potential therapeutic compound for PD and related disorders.
Abstract: Aggregation of amyloid-beta protein (Abeta) is a key pathogenic event in Alzheimer's disease (AD). Curcumin, a constituent of the Indian spice Turmeric is structurally similar to Congo Red and has been demonstrated to bind Abeta amyloid and prevent further oligomerization of Abeta monomers onto growing amyloid beta-sheets. Reasoning that oligomerization kinetics and mechanism of amyloid formation are similar in Parkinson's disease (PD) and AD, we investigated the effect of curcumin on alpha-synuclein (AS) protein aggregation. In vitro model of AS aggregation was developed by treatment of purified AS protein (wild-type) with 1 mM Fe3+ (Fenton reaction). It was observed that the addition of curcumin inhibited aggregation in a dose-dependent manner and increased AS solubility. The aggregation-inhibiting effect of curcumin was next investigated in cell culture utilizing catecholaminergic SH-SY5Y cell line. A model system was developed in which the red fluorescent protein (DsRed2) was fused with A53T mutant of AS and its aggregation examined under different concentrations of curcumin. To estimate aggregation in an unbiased manner, a protocol was developed in which the images were captured automatically through a high-throughput cell-based screening microscope. The obtained images were processed automatically for aggregates within a defined dimension of 1-6 microm. Greater than 32% decrease in mutant alpha-synuclein aggregation was observed within 48 h subsequent to curcumin addition. Our data suggest that curcumin inhibits AS oligomerization into higher molecular weight aggregates and therefore should be further explored as a potential therapeutic compound for PD and related disorders.
TL;DR: Curcumin and resveratrol are able to inhibit TNFα-activated NF-κB signaling in adipocytes and as a result significantly reduce cytokine expression, suggesting that curcumin may provide a novel and safe approach to reduce or inhibit the chronic inflammatory properties of adipose tissue.
Abstract: Adipocytes express inflammatory mediators that contribute to the low-level, chronic inflammation found in obese subjects and have been linked to the onset of cardiovascular disorders and insulin resistance associated with type 2 diabetes mellitus. A reduction in inflammatory gene expression in adipocytes would be expected to reverse this low-level, inflammatory state and improve cardiovascular function and insulin sensitivity. The natural products, curcumin and resveratrol, are established anti-inflammatory compounds that mediate their effects by inhibiting activation of NF-κB signaling. In the present study, we examined if these natural products can inhibit NF-κB activation in adipocytes and in doing so reduce cytokine expression. Cytokine (TNF-α, IL-1β, IL-6) and COX-2 gene expression in 3T3-L1-derived adipocytes was measured by quantitative real-time PCR (qRT-PCR) with or without TNFα-stimulation. Cytokine protein and prostaglandin E2 (PGE2) expression were measured by ELISA. Effects of curcumin and resveratrol were evaluated by treating TNFα-stimulated adipocytes with each compound and 1) assessing the activation state of the NF-κB signaling pathway and 2) measuring inflammatory gene expression by qRT-PCR and ELISA. Both preadipocytes and differentiated adipocytes express the genes for TNF-α, IL-6, and COX-2, key mediators of the inflammatory response. Preadipocytes were also found to express IL-1β; however, IL-1β expression was absent in differentiated adipocytes. TNF-α treatment activated NF-κB signaling in differentiated adipocytes by inducing IκB degradation and NF-κB translocation to the nucleus, and as a result increased IL-6 (6-fold) and COX-2 (2.5-fold) mRNA levels. TNF-α also activated IL-1β gene expression in differentiated adipocytes, but had no effect on endogenous TNF-α mRNA levels. No detectable TNFα or IL-1β was secreted by adipocytes. Curcumin and resveratrol treatment inhibited NF-κB activation and resulted in a reduction of TNF-α, IL-1β, IL-6, and COX-2 gene expression (IC50 = 2 μM) and a reduction of secreted IL-6 and PGE2 (IC50 ~ 20 μM). Curcumin and resveratrol are able to inhibit TNFα-activated NF-κB signaling in adipocytes and as a result significantly reduce cytokine expression. These data suggest that curcumin and resveratrol may provide a novel and safe approach to reduce or inhibit the chronic inflammatory properties of adipose tissue.
TL;DR: It is suggested that curcumin potentiates the antitumor effects of radiation therapy in colorectal cancer by suppressing NF-κB and NF-σκB–regulated gene products, leading to inhibition of proliferation and angiogenesis.
Abstract: Purpose: How colorectal cancer develops resistance to γ-radiation is not fully understood, but the transcription factor nuclear factor-κB (NF-κB) and NF-κB–regulated gene products have been proposed as mediators. Because curcumin, a component of turmeric ( Curcuma longa ), has been shown to suppress NF-κB activation, whether it can sensitize the colorectal cancer to γ-radiation was investigated in colorectal cancer xenografts in nude mice. Experimental Design: We established HCT 116 xenograft in nude mice, randomized into four groups, and treated with vehicle (corn oil), curcumin, γ-radiation, and curcumin in combination with γ-radiation. NF-κB modulation was ascertained using electrophoretic mobility shift assay and immunohistochemistry. Markers of proliferation, angiogenesis, and invasion were monitored by immunohistochemistry and Western blot analysis. Results: Curcumin significantly enhanced the efficacy of fractionated radiation therapy by prolonging the time to tumor regrowth ( P = 0.02) and by reducing the Ki-67 proliferation index ( P P = 0.002 versus radiation alone). Conclusion: Collectively, our results suggest that curcumin potentiates the antitumor effects of radiation therapy in colorectal cancer by suppressing NF-κB and NF-κB–regulated gene products, leading to inhibition of proliferation and angiogenesis.