Curcumin may impair iron status when fed to mice for six months

Mefloquine-curcumin combinations improve host mitochondrial respiration and decrease mitotoxic effects of mefloquine in Plasmodium berghei-infected mice

Plasmodium infection is a health challenge. Although, antiplasmodial drugs kill the parasites, information on the effects of infection and drugs on the expression of some genes is limited. Malaria was induced in two different studies using NK65 (chloroquine-susceptible, study 1), and ANKA (chloroquine-resistant, study 2) strains of Plasmodium berghei in 30 male Swiss mice (n = 5) in each study. Mice orally received 10 mL/kg distilled water, (infected control), Mefloquine (MF) (10 mg/kg), MF and Curcumin (CM) (25 mg/kg), MF and CM (50 mg/kg), CM (25 mg/kg) and CM (50 mg/kg). Five mice (un-infected) were used as the control. After treatment, total Ribonucleic acid (RNA) was isolated from liver and erythrocytes while Deoxyribonucleic acid (DNA)-free RNA were converted to cDNA. Polymerase Chain Reaction (PCR) amplification was performed and relative expressions of FIKK12, AQP3, P38 MAPK, NADH oxidoreductase, and cytochrome oxidase expressions were determined. Markers of glycolysis, toxicity and antioxidants were determined using ELISA assays. While the expression of FIKK12 was blunted by MF in the susceptible study, co-treatment with curcumin (25 mg/kg) yielded the same results in the chloroquine-resistant study. Similar results were obtained on AQP3 in both studies. Curcumin decreased P38 MAPK in both studies. Plasmodium infection decreased NADH oxidoreductase and cytochrome oxidase but mefloquine-curcumin restored the expression of these genes. While glycolysis and toxicity were inhibited, antioxidant systems improved in the treated groups. Curcumin is needed for effective therapeutic efficacy and prevention of toxicity. Plasmodium infection and treatment modulate the expressions of some genes in the host. Curcumin combination with mefloquine modulates the expression of some genes in the host.

The effect of curcumin supplementation on functional strength outcomes and markers of exercise-induced muscle damage: A systematic review and meta-analysis

Background: Curcumin is a polyphenol derived from the Curcuma longa L (turmeric) plant and has gained attention through its perceived anti-inflammatory characteristics. The potential interaction with exercise-induced muscle damage (EIMD) and delayed onset muscle soreness (DOMS) has led to investigation of curcumin as a post-exercise strategy that may have the potential to lessen acute reductions in functional strength (FS) following physical activity. Aim: The purpose of this review is to assess the evidence examining curcumin in relation to four outcome measures: FS, EIMD, DOMS and inflammation. Methods: A Medline, SPORTDiscus and CINAHL database search was undertaken with no publication date limit. Sixteen papers met the inclusion criteria and were included in this review. Three meta-analyses were completed for EIMD, DOMS and inflammation, respectively, with FS being excluded due to limited research. Results: Effect sizes were as follows: EIMD (0.15, -0.12, -0.04, -0.2 and -0.61 corresponding to 0, 24, 48, 72 and 96 h post-exercise, respectively), DOMS (-0.64, -0.33, 0.06, -0.53 and -1.16 corresponding to 0, 24, 48, 72 and 96 h post-exercise, respectively) and inflammation (-0.10, 0.26, 0.15 and 0.26 corresponding to 0, 24, 48 and 72 h post-exercise, respectively). A 96 h post-exercise inflammation meta-analysis was not conducted due to limited data. Conclusion: No effect sizes were statistically significant for EIMD (p = 0.644, 0.739, 0.893, 0.601 and 0.134), DOMS (p = 0.054, 0.092, 0.908, 0.119 and 0.074) and inflammation (p = 0.729, 0.603, 0.611 and 0.396). Further research is needed to thoroughly examine whether an effect exists.

Reduced iron and cobalt levels in response to curcumin supplementation are not responsible for the prolonged larval development and do not affect the oxidative stress tolerance and polyamine status of D. melanogaster

Recent reports indicated that the phytochemical curcumin possesses iron-chelating activity. Here, by employing the fruit fly Drosophila melanogaster, we conducted feeding studies supplementing curcumin or, as a control, the iron chelator bathophenanthroline (BPA). First, the absorption and further metabolization of dietary curcuminoids were proved by metabolomics analyses. Next, we found that 0.2% dietary curcumin, similar to BPA, lowered the iron but also the cobalt content, and to a lesser extent affected the manganese and zinc status. Supplementation during larval stages was required and sufficient for both compounds to elicit these alterations in adult animals. However, curcumin-induced retarded larval development was not attributable to the changed trace metal status. In addition, a reduction in the iron content of up to 70% by curcumin or BPA supplementation did not reduce heme-dependent catalase activity and tolerance toward H2 O2 in D. melanogaster. Moreover, polyamines were not influenced by curcumin treatment and decreased iron levels. This was confirmed for selected organs from 0.2% curcumin-treated mice, except for the spleen. Here, elevated spermidine level and concomitant upregulation of genes involved in polyamine production were associated with a putatively anemia-derived increased spleen mass. Our data underline that the metal-chelating property of curcumin needs to be considered in feeding studies.

Effect of curcumin on inflammatory biomarkers and iron profile in patients with premenstrual syndrome and dysmenorrhea: A randomized controlled trial

Premenstrual syndrome (PMS) and primary dysmenorrhea are common gynecological problems and inflammation may have a role in their etiology. Curcumin is a polyphenolic natural product for which there is increasing evidence of anti-inflammatory and iron chelation effects. This study assessed the effects of curcumin on inflammatory biomarkers and iron profile in young women with PMS and dysmenorrhea. A sample of 76 patients was included in this triple-blind, placebo-controlled clinical trial. Participants were randomly allocated to curcumin (n = 38) and control groups (n = 38). Each participant received one capsule (500 mg of curcuminoid+ piperine, or placebo) daily, from 7 days before until 3 days after menstruation for three consecutive menstrual cycles. Serum iron, ferritin, total iron-binding capacity (TIBC) and high-sensitivity C-reactive protein (hsCRP), as well as white blood cell, lymphocyte, neutrophil, platelet counts, mean platelet volume (MPV) and red blood cell distribution width (RDW), were quantified. Neutrophil: lymphocyte ratio (NLR), platelet: lymphocyte ratio (PLR), and RDW: platelet ratio (RPR) were also calculated. Curcumin significantly decreased the median (interquartile range) serum levels of hsCRP [from 0.30 mg/L (0.0-1.10) to 0.20 mg/L (0.0-1.3); p = 0.041] compared with placebo, but did not show any difference for neutrophil, RDW, MPV, NLR, PLR and RPR values (p > 0.05). The treatment schedule was well-tolerated, and none of markers of iron metabolism statistically changed after the intervention in the curcumin group (p > 0.05). Curcumin supplementation may have positive effects on serum hsCRP, a marker of inflammation, with no any changes on iron homeostasis in healthy women with PMS and dysmenorrhea.

What can traditional Chinese medicine do for adult neurogenesis?

Adult neurogenesis plays a crucial role in cognitive function and mood regulation, while aberrant adult neurogenesis contributes to various neurological and psychiatric diseases. With a better understanding of the significance of adult neurogenesis, the demand for improving adult neurogenesis is increasing. More and more research has shown that traditional Chinese medicine (TCM), including TCM prescriptions (TCMPs), Chinese herbal medicine, and bioactive components, has unique advantages in treating neurological and psychiatric diseases by regulating adult neurogenesis at various stages, including proliferation, differentiation, and maturation. In this review, we summarize the progress of TCM in improving adult neurogenesis and the key possible mechanisms by which TCM may benefit it. Finally, we suggest the possible strategies of TCM to improve adult neurogenesis in the treatment of neuropsychiatric disorders.

A Comprehensive Review on the Benefits and Problems of Curcumin with Respect to Human Health

Curcumin is the most important active component in turmeric extracts. Curcumin, a natural monomer from plants has received a considerable attention as a dietary supplement, exhibiting evident activity in a wide range of human pathological conditions. In general, curcumin is beneficial to human health, demonstrating pharmacological activities of anti-inflammation and antioxidation, as well as antitumor and immune regulation activities. Curcumin also presents therapeutic potential in neurodegenerative, cardiovascular and cerebrovascular diseases. In this review article, we summarize the advancements made in recent years with respect to curcumin as a biologically active agent in malignant tumors, Alzheimer’s disease (AD), hematological diseases and viral infectious diseases. We also focus on problems associated with curcumin from basic research to clinical translation, such as its low solubility, leading to poor bioavailability, as well as the controversy surrounding the association between curcumin purity and effect. Through a review and summary of the clinical research on curcumin and case reports of adverse effects, we found that the clinical transformation of curcumin is not successful, and excessive intake of curcumin may have adverse effects on the kidneys, heart, liver, blood and immune system, which leads us to warn that curcumin has a long way to go from basic research to application transformation.

The efficacy of curcumin-piperine co-supplementation on clinical symptoms, duration, severity, and inflammatory factors in COVID-19 outpatients: a randomized double-blind, placebo-controlled trial

BACKGROUND

COVID-19 pandemic has made the disease a major global problem by creating a significant burden on health, economic, and social status. To date, there are no effective and approved medications for this disease. Curcumin as an anti-inflammatory agent can have a positive effect on the control of COVID-19 complications. This study aimed to assess the efficacy of curcumin-piperine supplementation on clinical symptoms, duration, severity, and inflammatory factors in patients with COVID-19.

METHODS

Forty-six outpatients with COVID-19 disease were randomly allocated to receive two capsules of curcumin-piperine; each capsule contained 500 mg curcumin plus 5 mg piperine or placebo for 14 days.

RESULTS

Mean changes in complete blood count, liver enzymes, blood glucose levels, lipid parameters, kidney function, and c-reactive protein (CRP) were not significantly different between the two groups. There was a significant improvement in health status, including dry cough, sputum cough, ague, sore throat, weakness, muscular pain, headache, and dyspnea at week 2 in both curcumin-piperine and placebo groups (P value < 0.05); however, the improvement in weakness was more in the curcumin-piperine group than with placebo group (P value 025).

CONCLUSION

The present study results showed that curcumin-piperine co-supplementation in outpatients with COVID-19 could significantly reduce weakness. However, in this study, curcumin-piperine co-supplementation could not significantly affect the other indices, including biochemical and clinical indices.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials IRCT20121216011763N46 . 2020-10-31.

Iron Metabolism in Aging and Age-Related Diseases

Iron is a trace metal element necessary to maintain life and is also involved in a variety of biological processes. Aging refers to the natural life process in which the physiological functions of the various systems, organs, and tissues decline, affected by genetic and environmental factors. Therefore, it is imperative to investigate the relationship between iron metabolism and aging-related diseases, including neurodegenerative diseases. During aging, the accumulation of nonheme iron destroys the stability of the intracellular environment. The destruction of iron homeostasis can induce cell damage by producing hydroxyl free radicals, leading to mitochondrial dysfunction, brain aging, and even organismal aging. In this review, we have briefly summarized the role of the metabolic process of iron in the body, then discussed recent developments of iron metabolism in aging and age-related neurodegenerative diseases, and finally, explored some iron chelators as treatment strategies for those disorders. Understanding the roles of iron metabolism in aging and neurodegenerative diseases will fill the knowledge gap in the field. This review could provide new insights into the research on iron metabolism and age-related neurodegenerative diseases.

Co-Administration of Iron and Bioavailable Curcumin Reduces Levels of Systemic Markers of Inflammation and Oxidative Stress in a Placebo-Controlled Randomised Study

Ferrous sulphate (FS) is widely used as an iron supplement to treat iron deficiency (ID), but is known to induce inflammation causing gastric side-effects resulting in poor adherence to supplement regimens. Curcumin, a potent antioxidant, has been reported to suppress inflammation via down regulation of NF-κB. The aim of the present double blind, placebo-controlled randomised trial was to assess whether co-administration of FS with a formulated, bioavailable form of curcumin (HydroCurc™) could reduce systemic inflammation and/or gastrointestinal side-effects. This study recruited 155 healthy participants (79 males; 26.42 years ± 0.55 and 76 females; 25.82 years ± 0.54), randomly allocated to one of five different treatment groups: iron and curcumin placebo (FS0_Plac), low dose (18 mg) iron and curcumin placebo (FS18_Plac), low dose iron and curcumin (FS18_Curc), high dose (65 mg) iron and curcumin placebo (FS65_Plac), and high dose iron and curcumin (FS65_Curc). Completed questionnaires and blood samples were collected from all participants at baseline (day 1), mid-point (day 21), and at end-point (day 42). Results showed a significant reduction in IL-6 in the FS65_Curc group (0.06 pg/mL ± 0.02, p = 0.0073) between the mid-point and end-point. There was also a significant reduction in mean plasma TNF levels in the FS65_Curc (0.65 pg/mL ± 0.17, p = 0.0018), FS65_Plac (0.39 pg/mL ± 0.15, p = 0.0363), and FS18_Curc (0.35 pg/mL ± 0.13, p = 0.0288) groups from mid-point to end-point. A significant increase was observed in mean plasma TBARS levels (0.10 µM ± 0.04, p = 0.0283) in the F18_Plac group from baseline to end-point. There was a significant association with darker stools between FS0_Plac vs. FS65_Plac (p = 0.002, Fisher's exact test) suggesting that high iron dose in the absence of curcumin leads to darker stools. A reduction in inflammation-related markers in response to co-administering supplemental iron alongside formulated curcumin suggests a reduction in systemic inflammation. This supplementation approach may therefore be a more cost effective and convenient alternative to current oral iron-related treatments, with further research to be conducted.

Triad role of hepcidin, ferroportin, and Nrf2 in cardiac iron metabolism: From health to disease

Iron is an essential trace element required for several vital physiological and developmental processes, including erythropoiesis, bone, and neuronal development. Iron metabolism and oxygen homeostasis are interlinked to perform a vital role in the functionality of the heart. The metabolic machinery of the heart utilizes almost 90 % of oxygen through the electron transport chain. To handle this tremendous level of oxygen, the iron metabolism in the heart is utmost crucial. Iron availability to the heart is therefore tightly regulated by (i) the hepcidin/ferroportin axis, which controls dietary iron absorption, storage, and recycling, and (ii) iron regulatory proteins 1 and 2 (IRP1/2) via hypoxia inducible factor 1 (HIF1) pathway. Despite iron being vital to the heart, recent investigations have demonstrated that iron imbalance is a common manifestation in conditions of heart failure (HF), since free iron readily transforms between Fe²⁺ and Fe³⁺via the Fenton reaction, leading to reactive oxygen species (ROS) production and oxidative damage. Therefore, to combat iron-mediated oxidative stress, targeting Nrf2/ARE antioxidant signaling is rational. The involvement of Nrf2 in regulating several genes engaged in heme synthesis, iron storage, and iron export is beginning to be uncovered. Consequently, it is possible that Nrf2/hepcidin/ferroportin might act as an epicenter connecting iron metabolism to redox alterations. However, the mechanism bridging the two remains obscure. In this review, we tried to summarize the contemporary insight of how cardiomyocytes regulate intracellular iron levels and discussed the mechanisms linking cardiac dysfunction with iron imbalance. Further, we emphasized the impact of Nrf2 on the interplay between systemic/cardiac iron control in the context of heart disease, particularly in myocardial ischemia and HF.

Curcumin, a potent therapeutic nutraceutical and its enhanced delivery and bioaccessibility by pickering emulsions

Curcumin is a biomolecule with functional moieties, which contribute to its anti-inflammatory, anticancer, and antioxidant properties. It has shown several therapeutic effects on treating inflammatory and neurodegenerative diseases and contributes to the reduction of oxidative stress and damage to body tissues. However, its low solubility and fast metabolism limit its absorption in the gastrointestinal (GI) tract and lead to its low bioavailability. Preparation of Pickering emulsions stabilized with mineral or biopolymer-based nanoparticles can be an effective strategy for enhancing the stability of curcumin against degradation, increasing its bioaccessibility in the GI tract, and achieving its controlled release at various locations based on changes in environmental conditions. Various nanoparticles prepared from minerals, proteins, and polysaccharides show potential for stabilizing the curcumin-loaded emulsions, and their wettability can be altered through complexation and formation of hybrid nanoparticles. Stabilization of Pickering emulsions with polysaccharide-based nanoparticles and their complexes can enhance the stability of the curcumin against degradation. Moreover, various protein-based nanoparticles and their conjugated forms with other proteins or polysaccharides can enable the preparation of high internal phase Pickering emulsions (HIPEs) with concomitant higher loading and bioaccessibility of the curcumin molecule. In light of the several therapeutic properties of curcumin, this review article aims to highlight recent studies and the strategies used for the preparation of curcumin Pickering emulsions stabilized by various nanoparticles for enhancing its bioaccessibility during metabolism. These may be useful in pharmaceutical and food industries for drug development and delivery and fortification of food products with this nutraceutical component.

Targeting long non coding RNA by natural products: Implications for cancer therapy

In spite of achieving substantial progress in its therapeutic strategies, cancer-associated prevalence and mortality are persistently rising globally. However, most malignant cancers either cannot be adequately diagnosed at the primary phase or resist against multiple treatments such as chemotherapy, surgery, radiotherapy as well as targeting therapy. In recent decades, overwhelming evidences have provided more convincing words on the undeniable roles of long non-coding RNAs (lncRNAs) in incidence and development of various cancer types. Recently, phytochemical and nutraceutical compounds have received a great deal of attention due to their inhibitory and stimulatory effects on oncogenic and tumor suppressor lncRNAs respectively that finally may lead to attenuate various processes of cancer cells such as growth, proliferation, metastasis and invasion. Therefore, application of phytochemicals with anticancer characteristics can be considered as an innovative approach for treating cancer and increasing the sensitivity of cancer cells to standard prevailing therapies. The purpose of this review was to investigate the effect of various phytochemicals on regulation of lncRNAs in different human cancer and evaluate their capabilities for cancer treatment and prevention.

Iron: an underrated factor in aging

Iron is an essential element for virtually all living organisms, but its reactivity also makes it potentially harmful. Iron accumulates with aging, and is associated with many age-related diseases; it also shortens the lifespans of several model organisms. Blocking iron absorption through drugs or natural products extends lifespan. Many life-extending interventions, such as rapamycin, calorie restriction, and old plasma dilution can be explained by the effects they have on iron absorption, excretion, and metabolism. Control of body iron stores so that they remain in a low normal range may be an important, lifespan- and healthspan-extending intervention.

Curcumin Reduces Adipose Tissue Inflammation and Alters Gut Microbiota in Diet-Induced Obese Male Mice

SCOPE

Obesity prevalence continues to increase and contribute to metabolic diseases, potentially by driving systemic inflammation. Curcumin is an anti-inflammatory spice with claimed health benefits. However, mechanisms by which curcumin may reduce obesity-associated inflammation are poorly understood; thus, it is hypothesized that benefits of curcumin consumption may occur through reduced white adipose tissue (WAT) inflammation and/or beneficial changes in gut bacteria.

METHODS AND RESULTS

Male B6 mice are fed high-fat diets (HFD, 45% kcal fat) or HFD supplemented with 0.4% (w/w) curcumin (HFC) for 14 weeks. Curcumin supplementation significantly reduces adiposity and total macrophage infiltration in WAT, compared to HFD group, consistent with reduced mRNA levels of M1 (Cd80, Cd38, Cd11c) and M2 (Arginase-1) macrophage markers. Moreover, curcumin supplementation reduces expression of other key pro-inflammatory genes, such as NF-κB p65 subunit (p65), Stat1, Tlr4, and Il6, in WAT (p < 0.05). Using microbial 16S RNA sequencing, it is demonstrated that the relative abundance of the Lactococcus, Parasutterella, and Turicibacter genera are increased in the HFC group versus HFD.

CONCLUSIONS

Curcumin exerts protective metabolic effects in dietary obesity, in part through downregulation of adipose tissue inflammation, which may be mediated by alterations in composition of gut microbiota, and metabolism of curcumin into curcumin-O-glucuronide.

Acute Administration of Bioavailable Curcumin Alongside Ferrous Sulphate Supplements Does Not Impair Iron Absorption in Healthy Adults in a Randomised Trial

Ferrous sulphate (FS) is a cost effective, readily available iron supplement for iron deficiency (ID). The pro-oxidant effect of oral ferrous iron is known to induce inflammation, causing gastric side-effects and resulting in poor compliance. Curcumin is a potent antioxidant and has also been shown to exhibit iron chelation in-vitro, although it is not established whether these effects are retained in-vivo. The aim of this study was therefore to assess the influence of a formulated bioavailable form of curcumin (HydroCurc^TM; 500 mg) on acute iron absorption and status in a double blind, placebo-controlled randomized trial recruiting 155 healthy participants (79 males; 26.42 years ± 0.55 and 76 females; 25.82 years ± 0.54). Participants were randomly allocated to five different treatment groups: iron and curcumin placebo (FS0_Plac), low dose (18 mg) iron and curcumin placebo (FS18_Plac), low dose iron and curcumin (FS18_Curc), high dose (65 mg) iron and curcumin placebo (FS65_Plac), and high dose iron and curcumin (FS65_Curc). Participants were provided with the supplements according to their relevant treatment groups at baseline (0 min), and blood collection was carried out at 0 min and at 180 min following supplementation. In the treatment groups, significant difference was observed in mean serum iron between baseline (0 min) and at end-point (180 min) (F (1, 144) = 331.9, p < 0.0001) with statistically significant intra-group increases after 180 min (p < 0.0001) in the FS18_Plac (8.79 µmol/L), FS18_Curc (11.41 µmol/L), FS65_Plac (19.09 µmol/L), and FS65_Curc (16.39 µmol/L) groups. A significant difference was also observed between the two time points in serum TIBC levels and in whole blood haemoglobin (HGB) in the treatment groups, with a significant increase (1.55%/2.04 g/L) in HGB levels from baseline to end-point observed in the FS65_Curc group (p < 0.05). All groups receiving iron demonstrated an increase in transferrin saturation (TS%) in a dose-related manner, demonstrating that increases in serum iron are translated into increases in physiological iron transportation. This study demonstrates, for the first time, that regardless of ferrous dose, formulated curcumin in the form of HydroCurc™ does not negatively influence acute iron absorption in healthy humans.

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

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

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

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

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

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

Iron biodistribution profile changes in the rat spleen after administration of high-fat diet or iron supplementation and the role of curcumin

Curcumin as active metal chelating and antioxidant agent has a potential role in metal reduction and free radicals' neutralization in tissues. Of note, long-term administration of high fat diet (HFD) is considered as a main factor of blood serum iron deficiency. This study aimed to investigate the biodistribution profiles of iron in the spleen after long-term administration of HFD along with iron supplementation. Furthermore, the ameliorative role of curcumin to reduce iron accumulation level and improve the histological abnormalities produced by iron in spleen will be evaluated in the rats. Treated albino rats of this experiment were divided into six groups. Group I was a control group where group II was treated with HFD. Group III and group IV were treated with combination of HFD and curcumin or HFD and iron supplement respectively. Additionally, group V and group VI were treated with combination of HFD, iron supplement and curcumin or curcumin only respectively. Mainly histological analysis was used to investigate iron biodistribution and induced abnormalities in spleen under light microscope. The histochemical specific staining of iron in the spleen showed different biodistribution profiles of iron in the spleen. Administration of the HFD or HFD and iron supplementation increased the iron accumulation in the spleen. Where, curcumin administration with HFD (Group III) or with HFD and iron supplementation (Group V) significantly reduced the iron levels in the spleen. The splenic tissue inflammation, cellular apoptosis and fibrosis produced by higher iron accumulation was ameliorated after administration of curcumin supplementation as shown in the animals treated with HFD/curcumin (Group III) or HFD/iron supplement/curcumin (Group V). This study recommended that, it is preferable to use iron supplementation along with curcumin supplement for less than 4 months to avoid additional iron accumulation in the healthy organs.

How curcumin affects hyperglycemia-induced optic nerve damage: A short review

Considered to be one of the most important non-contagious systemic diseases worldwide, diabetes mellitus is still a topical issue on the health agenda with the problems it causes. Exposure to long-term hyperglycemia causes diabetic complications (diabetic neuropathy, nephropathy and retinopathy). The optic nerve can suffer damage by both diabetic retinopathy and neuropathy during diabetes, both because it is formed by axons of retinal ganglion cells and these axons belong to the central nervous system. The issue of hyperglycemia on the optic nerve have been described as diabetic papillopathy, posterior ischemic optic neuropathy, nonarteritic anterior ischemic optic neuropathy and optic atrophy in clinical studies. Experimental studies indicated axon-myelin degeneration in addition to microvascular and ultrastructural changes caused by the hyperglycemia-induced optic nerve damage. Although there are several proposed biochemical mechanisms to cause these damages, oxidative stress emerges as an important factor among them. Oxidative stress leads to pathological state on the nerve cells by affecting the DNA, protein and lipids at different levels. These are causing deterioration on nerve conduction velocity, myelin sheath and nerve structure, neurotrophic support system, glial cells and nerve function. Curcumin, as an important antioxidant, can be an ideal prophylactic agent to eliminate damages on optic nerve. Curcumin helps to regulate the balance of antioxidant and reactive oxygen species by targeting various molecules (NF-κB, STAT3, MAPK, Mfn2, Nrf2, pro-inflammatory cytokines). In addition, it shows healing or preventive effects on myelin sheath damage via regulating ferritin protein in oligodendrocytes. It is also effective in preventing neurovascular damage.

Strain specific response of mice to IMQ-induced psoriasis

OBJECTIVES

Psoriasis is an autoimmune, inflammatory disease that needs a reliable animal model. Imiquimod (IMQ)-induced psoriasis is a widely used preclinical tool for psoriasis research. However, this model is sensitive to the genetic variation of mice. The present study explores mice's genetic background on disease stability and severity induced by IMQ.

METHODS

Three distinct strains of mice (Balb/c, C57BL/6, and Swiss albino) were divided into four groups (Vaseline, IMQ, IMQ+Clobetasol, and IMQ+Curcumin). Psoriasis area severity index (PASI) score, ear/back skin thickness, body weight alterations, and histopathological examination were employed to analyze disease severity. The spleen index studied the systemic effect. Strain effect on oxidative stress induced by IMQ was evaluated by estimating antioxidant factors, superoxide dismutase (SOD), catalase, and glutathione (GSH).

RESULTS

IMQ application resulted in increased PASI score, thickness, and alterations in body weight, confirming disease development in all the mice. However, the disease stability/severity between these strains was not identical. Although IMQ application caused splenomegaly, IMQ+curcumin treated C57BL/6 mice demonstrated a synergistic effect of IMQ and curcumin on the spleen resulting in increased splenomegaly. Decreased cellular enzyme activity in SOD, Catalase, and levels of GSH was observed in IMQ challenged mice, indicating the participation of the redox system in the genesis of the disease that was comparable among the strains.

CONCLUSIONS

These results indicate the existence of strain-dependent development of the disease. The Swiss model was found to be better in terms of disease severity and stability than other models. Further, a detailed mechanistic study might help to explain the pathological difference between these strains.

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.

The Action of JAK/STAT3 and BMP/HJV/SMAD Signaling Pathways on Hepcidin Suppression by Tucum-do-Cerrado in a Normal and Iron-Enriched Diets

The Brazilian savanna fruit, tucum-do-cerrado (Bactris setosa Mart.) reduces hepatic hepcidin levels. Therefore, we investigated the effect of tucum-do-cerrado on the TfR/HFE and/or BMP/HJV/SMAD and JAK/STAT pathways, in normal and excess iron conditions. Rats were treated with: control diet (CT); control diet +15% tucum-do-cerrado (Tuc); iron-enriched diet (+Fe); or iron-enriched diet +15% tucum-do-cerrado (Tuc+Fe). Tucum-do-cerrado (Tuc) decreased hepatic Hamp and Hjv mRNA levels but did not alter Bmp6, Smad7, Tfr1, and Hfe mRNA levels; pSMAD1/5/8 and pSTAT3 protein levels; labile iron pool (LIP); and inflammatory biomarkers, compared to the CT group. The iron-enriched diet increased Hamp mRNA levels, as well as pSMAD1/5/8 and pSTAT3 protein levels, while no difference was observed in Hjv, Bmp6, Smad7, Tfr1, and Hfe mRNA levels and LIP compared to the CT group. The association of tucum-do-cerrado with the iron-enriched diet (Tuc+Fe) decreased Hamp, Hjv, Bmp6, and Hfe mRNA levels and pSTAT3 protein content compared to the +Fe group, while increased Hamp and decreased Hfe mRNA levels compared to the Tuc group. Therefore, the inhibition of hepatic hepcidin by tucum-do-cerrado consumption may involve the downregulation of intestinal Dmt1 and hepatic Hjv expression and deacetylation mediated by SIRT1 by a mechanism that is independent of tissue iron content. However, in excess iron conditions, the modulation of hepatic hepcidin expression by tucum-do-cerrado seems to be partially mediated by the inflammatory signaling pathway, as well as involves the chelating activity of tucum-do-cerrado.

Combating iron overload: a case for deferoxamine-based nanochelators

While iron is a nutrient metal, iron overload can result in multiple organ failures. Iron chelators, such as deferoxamine, are commonly used to ameliorate iron overload conditions. However, their uses are limited due to poor pharmacokinetics and adverse effects. Many novel chelator formulations have been developed to overcome these drawbacks. In this review, we have discussed various nanochelators, including linear and branched polymers, dendrimers, polyrotaxane, micelles, nanogels, polymeric nanoparticles and liposomes. Although these research efforts have mainly been focused on nanochelators with longer half-lives, prolonged residence of polymers in the body could raise potential safety issues. We also discussed recent advances in nanochelation technologies, including mechanism-based, long-acting nanochelators.

Insights on the synthesis of asymmetric curcumin derivatives and their biological activities

Curcumin is a small organic molecule with pleiotropic biological activities. However, its multiple structural-pharmacokinetic challenges prevent its development into a clinical drug. Various structural modifications have been made to improve its drug profile. In this review, we focus on the methods adopted in the synthesis of asymmetric curcumin derivatives and their biological activities and forecast the future of this exciting class of compounds in the field of medicine.

Colonic Injuries Induced by Inhalational Exposure to Particulate-Matter Air Pollution

Particulate matter (PM) exposure has been associated with intestinal disorders. Therefore, there is an urgent need to understand the precise molecular mechanism involved and explore potential prevention strategies. In this study, inhaled PM is shown to activate inflammatory pathways in murine colon. In a panel study, it is found that ambient PM levels are significantly associated with elevated number of fecal white blood cells in healthy subjects. Acting as a promoter, PM exposure accelerates chemical carcinogenesis-induced colonic tumor formation in a murine model. Mechanistically, RNA-seq assays suggest activation of phosphoinositide 3-kinase (PI3K)/AKT cascades in chronically PM-exposed human colon mucosal epithelial cells. Ablation of up-stream driver fibroblast growth factor receptor 4 (FGFR4) effectively inhibits inflammation and neoplasia in PM-exposed murine colons. Notably, dietary curcumin supplement is shown to protect against PM-induced colonic injuries in mice. Collectively, these findings identify that PM exposure accelerates colonic tumorigenesis in a PI3K/AKT-dependent manner and suggests potential nutrient supplement for prevention.

The progresses in curcuminoids-based metal complexes: especially in cancer therapy

Curcuminoids (CURs), a series of derivatives in turmeric (Curcuma longa), are commonly discovered to control the deterioration of cancers. However, the physiochemical properties and the original side effects of many CURs complexes put barriers in their medical applications. To address them, the investigation of metal-based complexes with CURs is in progress. The complexes were summarized according to articles in recent years. The results showed that the complexes improved the physicochemical properties or therapeutic performances compared with pure CURs. Further, it is possible for the novel complexes to be applied in chemical detecting, paramagnetic-luminescent and bio-imaging fields. Therefore, the formation of the metal-based CURs complexes (MBCCs) is beneficial for the development of CURs especially in medical fields.

Curcumin induces mild anemia in a DSS-induced colitis mouse model maintained on an iron-sufficient diet

Anemia is frequently encountered in patients with inflammatory bowel disease (IBD), decreasing the quality of life and significantly worsening the prognosis of the disease. The pathogenesis of anemia in IBD is multifactorial and results mainly from intestinal blood loss in inflamed mucosa and impaired dietary iron absorption. Multiple studies have proposed the use of the polyphenolic compound curcumin to counteract IBD pathogenesis since it has significant preventive and therapeutic properties as an anti-inflammatory agent and very low toxicity, even at high dosages. However, curcumin has been shown to possess properties consistent with those of an iron-chelator, such as the ability to modulate proteins of iron metabolism and decrease spleen and liver iron content. Thus, this property may further contribute to the development and severity of anemia of inflammation and iron deficiency in IBD. Herein, we evaluate the effects of curcumin on systemic iron balance in the dextran sodium sulfate (DSS) model of colitis in C57Bl/6 and BALB/c mouse strains that were fed an iron-sufficient diet. In these conditions, curcumin supplementation caused mild anemia, lowered iron stores, worsened colitis and significantly decreased overall survival, independent of the mouse strain. These findings suggest that curcumin usage as an anti-inflammatory supplement should be accompanied by monitoring of erythroid parameters to avoid exacerbation of iron deficiency anemia in IBD.

NUPR1 acts as a pro-survival factor in human bone marrow-derived mesenchymal stem cells and is induced by the hypoxia mimetic reagent deferoxamine

Differences in the culturing conditions of mesenchymal stem cells used in regenerative medicine may affect their differentiation ability, genome instability, and therapeutic effects. In particular, bone marrow-derived mesenchymal stem cells cultured under hypoxia are known to proliferate while maintaining an undifferentiated state and the use of deferoxamine, a hypoxia mimetic reagent, has proven to be a suitable strategy to maintain the cells under hypoxic metabolic state. Here, the deferoxamine effects were investigated in mesenchymal stem cells to gain insights into the mechanisms regulating stem cell survival. A 12-h deferoxamine treatment reduced proliferation, oxygen consumption, mitochondrial activity, and ATP production. Microarray analysis revealed that deferoxamine enhanced the transcription of genes involved in glycolysis and the HIF1α pathway. Among the earliest changes, transcriptional variations were observed in HIF1α, NUPR1, and EGLN, in line with previous reports showing that short deferoxamine treatments induce substantial changes in mesenchymal stem cells glycolysis pathway. NUPR1, which is induced by stress and involved in autophagy-mediated survival, was upregulated by deferoxamine in a concentration-dependent manner. Consistently, NUPR1 knockdown was found to reduce cell proliferation and increase the proapoptotic effect of staurosporine, suggesting that deferoxamine-induced NUPR1 promotes mesenchymal stem cell survival and cytoprotective autophagy. Our findings may substantially contribute to improve the effectiveness of mesenchymal stem cell-based regenerative medicine.

Effects of Prolonged Dietary Curcumin Exposure on Skeletal Muscle Biochemical and Functional Responses of Aged Male Rats

Oxidative stress resulting from decreased antioxidant protection and increased reactive oxygen and nitrogen species (RONS) production may contribute to muscle mass loss and dysfunction during aging. Curcumin is a phenolic compound shown to upregulate antioxidant defenses and directly quench RONS in vivo. This study determined the impact of prolonged dietary curcumin exposure on muscle mass and function of aged rats. Thirty-two-month-old male F344xBN rats were provided a diet with or without 0.2% curcumin for 4 months. The groups included: ad libitum control (CON; n = 18); 0.2% curcumin (CUR; n = 18); and pair-fed (PAIR; n = 18) rats. CUR rats showed lower food intake compared to CON, making PAIR a suitable comparison group. CUR rats displayed larger plantaris mass and force production (vs. PAIR). Nuclear fraction levels of nuclear factor erythroid-2 related-factor-2 were greater, and oxidative macromolecule damage was lower in CUR (vs. PAIR). There were no significant differences in measures of antioxidant status between any of the groups. No difference in any measure was observed between CUR and CON rats. Thus, consumption of curcumin coupled with reduced food intake imparted beneficial effects on aged skeletal muscle. The benefit of curcumin on aging skeletal muscle should be explored further.

Iron Deficiency Anemia Due to High-dose Turmeric

Turmeric is increasingly studied as an anti-inflammatory and anti-neoplastic agent. It binds to ferric iron in the gut and causes iron deficiency in mice. We report here a possible case of iron deficiency anemia in a human taking turmeric.

A 66-year-old physician treated himself for an osteoarthritis flare after steroids with six turmeric extract capsules (538 mg) daily, to help with inflammation. During this time, his hemoglobin never rose above 12 and his iron and ferritin levels were consistent with iron deficiency. Upper and lower endoscopy and Hemoccult™ studies were negative. Two weeks after stopping the turmeric and continuing his usual iron supplement, his hemoglobin had returned to normal, with normalizing iron studies. Turmeric was associated with significant iron deficiency anemia, consistent with the binding of available iron in the gut and the prevention of absorption. This resolved after the turmeric was stopped, consistent with animal studies.

This may be the first case of documented iron deficiency anemia in people due to turmeric supplements. Given the widespread use of turmeric and curcumin supplements across many illnesses, further attention is warranted.

Iron Metabolism in Prostate Cancer; From Basic Science to New Therapeutic Strategies

An increasing amount of research has recently strengthened the case for the existence of iron dysmetabolism in prostate cancer. It is characterized with a wide array of differential expression of iron-related proteins compared to normal cells. These proteins control iron entry, cellular iron distribution but also iron exit from prostate cells. Iron dysmetabolism is not an exclusive feature of prostate cancer cells, but it is observed in other cells of the tumor microenvironment. Disrupting the machinery that secures iron for prostate cancer cells can retard tumor growth and its invasive potential. This review unveils the current understanding of the ways that prostate cancer cells secure iron in the tumor milieu and how can we exploit this knowledge for therapeutic purposes.

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.

An investigation of the effects of curcumin on iron overload, hepcidin level, and liver function in β-thalassemia major patients: A double-blind randomized controlled clinical trial

This study investigated the effects of curcumin, the active polyphenol in turmeric, on iron overload, hepcidin level, and liver function in β-thalassemia major patients. This double-blind randomized controlled clinical trial was conducted on 68 β-thalassemia major patients. The subjects were randomly divided into 2 groups to receive either 500 mg curcumin capsules (total: 1,000 mg) twice daily or placebo for 12 weeks. Dietary intakes and biochemical variables including hemoglobin, transferrin saturation, total iron binding capacity, nontransferrin bound iron (NTBI), ferritin, hepcidin, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were assessed at the beginning and end of the trial. Curcumin significantly reduced serum levels of NTBI (2.83 ± 1.08 compared with 2.22 ± 0.97 μmol/L, p = .001), ALT (42.86 ± 11.15 compared with 40.60 ± 9.89 U/L, p = .018), and AST (49.45 ± 12.39 compared with 46.30 ± 10.85 U/L, p = .002) at the end of the study. Based on analysis of covariance, a significant decrease was also observed in levels of NTBI (2.22 ± 0.97 vs. 2.55 ± 0.94 μmol/L, p = .026), ALT (40.60 ± 9.89 vs. 45.01 ± 10.42 U/L, p = .004), and AST (46.30 ± 10.85 vs. 50.99 ± 9.36 U/L, p = .009) in curcumin group in comparison with placebo group. There were no significant changes in hepcidin and other variables in any of the 2 groups. Curcumin administration alleviated iron burden and liver dysfunction by reducing NTBI, ALT, and AST levels in patients with β-thalassemia major.

Curcumin in turmeric: Basic and clinical evidence for a potential role in analgesia

WHAT IS KNOWN AND OBJECTIVE

Current analgesic pharmacotherapy-opioids, non-steroidal anti-inflammatory drugs (NSAIDs), acetaminophen (paracetamol) and related drugs-is effective for acute pain, but their use is limited by adverse effects on the renal, hepatic, cardiovascular or gastrointestinal systems, or they have potential for abuse. Therefore, alternative options are desired. Compounds used in traditional medicine might offer such alternatives, but the evidence must be based on pharmacologic properties and on clinical trial data. This review summarizes the evidence for one of these: the analgesic properties of turmeric and other curcumins.

METHODS

The PubMed database and other sources were searched using keywords related to turmeric, curcumin, antinociception and analgesia. Primary sources and reviews of preclinical and clinical studies were identified, assessed and summarized. Bibliographies within these sources provided additional information.

RESULTS

Turmeric has consistently been demonstrated to produce analgesic and anti-inflammatory effects in animal models and in clinical trials, and appears to have less serious adverse effects than many current analgesics.

WHAT IS NEW AND CONCLUSIONS

Turmeric (curcumin) appears to be a possible candidate for consideration for use as a stand-alone analgesic, or in analgesic combinations as part of opioid-, NSAID- or paracetamol (acetaminophen)-sparing strategies.

Supplementation with turmeric residue increased survival of the Chinese soft-shelled turtle (Pelodiscus sinensis) under high ambient temperatures

Turmeric residue (TR), containing residual levels of curcumin, is a solid by-product waste generated after the extraction and separation of curcumin from turmeric root. A feeding trial was conducted to evaluate the effects of TR on the survival of Chinese soft-shelled turtles (SSTs), Pelodiscus sinensis, under a high ambient temperature. A total of 320 female SSTs were assigned randomly to two diets: basal diet (the control group, n=160) and an interventional diet supplemented with 10% TR (the TR group, n=160). Our results demonstrated that supplementation of TR increased the SST survival rate by 135.5%, and superoxide dismutase (SOD) activity of SST liver by 112.8%, and decreased the malondialdehyde (MDA) content of SST liver by 36.4%, compared to the control group. The skin of the SST fed TR showed a golden color. High-performance liquid chromatography (HPLC) analysis indicated that the concentrations of curcumin in TR and the skin of the SST fed TR were (1.69±0.30) and (0.14±0.03) μg/g, respectively. Our observation suggests that supplementation of TR increased the survival rate of SST under high ambient temperatures. We speculated that the increased survival rate and tolerance at the high ambient temperature were associated with the anti-oxidation activity of curcumin from TR. Moreover, curcumin in TR could be deposited in SST skin, which made it more favored in the market of China. Our findings provide new knowledge and evidence to effectively reuse TR as a feed additive in animal and aquatic farming.

Plasma elemental responses to red meat ingestion in healthy young males and the effect of cooking method

PURPOSE

Elemental deficiencies are highly prevalent and have a significant impact on health. However, clinical monitoring of plasma elemental responses to foods remains largely unexplored. Data from in vitro studies show that red meat (beef) is a highly bioavailable source of several key elements, but cooking method may influence this bioavailability. We therefore studied the postprandial responses to beef steak, and the effects of two different cooking methods, in healthy young males.

METHODS

In a randomized cross-over controlled trial, healthy males (n = 12, 18-25 years) were fed a breakfast of beef steak (270 ± 20 g) in which the meat was either pan-fried (PF) or sous-vide (SV) cooked. Baseline and postprandial blood samples were collected and the plasma concentrations of 15 elements measured by inductively coupled plasma-mass spectrometry (ICP-MS).

RESULTS

Concentrations of Fe and Zn changed after meal ingestion, with plasma Fe increasing (p < 0.001) and plasma Zn decreasing (p < 0.05) in response to both cooking methods. The only potential treatment effect was seen for Zn, where the postprandial area under the curve was lower in response to the SV meal (2965 ± 357) compared to the PF meal (3190 ± 310; p < 0.05).

CONCLUSIONS

This multi-element approach demonstrated postprandial responsiveness to a steak meal, and an effect of the cooking method used. This suggests the method would provide insight in future elemental metabolic studies to evaluate responses to meat-based meals, including longer-term interventions in more specifically defined cohorts to clearly establish the role of red meat as an important source of elements.

Oral curcumin supplementation improves fine motor function in the middle-aged rhesus monkey

Aged individuals experience decreased fine motor function of the hand and digits, which could result, in part, from the chronic, systemic state of inflammation that occurs with aging. Recent research for treating age-related inflammation has focused on the effects of nutraceuticals that have anti-inflammatory properties. One particular dietary polyphenol, curcumin, the principal curcuminoid of the spice turmeric, has been shown to have significant anti-inflammatory effects and there is mounting evidence that curcumin may serve to reduce systemic inflammation. Therefore, it could be useful for alleviating age-related impairments in fine motor function. To test this hypothesis we assessed the efficacy of a dietary intervention with a commercially available optimized curcumin to ameliorate or delay the effects of aging on fine motor function of the hand of rhesus monkeys. We administered oral daily doses of curcumin or a control vehicle to 11 monkeys over a 14- to 18-month period in which they completed two rounds of fine motor function testing. The monkeys receiving curcumin were significantly faster at retrieving a food reward by round 2 of testing than monkeys receiving a control vehicle. Further, the monkeys receiving curcumin demonstrated a greater degree of improvement in performance on our fine motor task by round 2 of testing than monkeys receiving a control vehicle. These findings reveal that fine motor function of the hand and digits is improved in middle-aged monkeys receiving chronic daily administration of curcumin.

Benefits of Curcumin Supplementation on Antioxidant Status in β-Thalassemia Major Patients: A Double-Blind Randomized Controlled Clinical Trial

Background: β-Thalassemia major, the most common inherited anemia in the world, is associated with imbalance in the oxidant-antioxidant system. The objective of this study was to evaluate the efficacy of curcumin supplementation on markers of oxidative stress in patients with β-Thalassemia. Methods: This double-blind randomized controlled clinical trial was performed on 61 β-thalassemia major patients. Subjects in the curcumin group received two 500 mg curcumin capsules daily and patients in the placebo group took 2 placebo capsules daily for 12 weeks. Dietary intakes and biochemical parameters were assessed at the beginning and the end of intervention. Results: At the end of the study, serum malondialdehyde (MDA), total and direct bilirubin significantly decreased (p = 0.002, p < 0.001, and p < 0.001, respectively) and total antioxidant capacity significantly increased (p = 0.005) in the curcumin group. Based on the analysis of covariance, a significant reduction in MDA, total and direct bilirubin was also detected in the curcumin group when compared to the placebo group (p = 0.001, p = 0.039, and p = 0.013, respectively). Changes in hemoglobin, serum iron, ferritin, catalase, and vitamin E were not significant in any of the 2 groups. Conclusions: Curcumin supplementation in combination with deferoxamin improved the antioxidant status in β-thalassemia major patients. Curcumin may be useful for the relief of metabolic complications in these patients.

Isolation and characterization of iron chelators from turmeric (Curcuma longa): selective metal binding by curcuminoids

Iron overload disorders may be treated by chelation therapy. This study describes a novel method for isolating iron chelators from complex mixtures including plant extracts. We demonstrate the one-step isolation of curcuminoids from turmeric, the medicinal food spice derived from Curcuma longa. The method uses iron-nitrilotriacetic acid (NTA)-agarose, to which curcumin binds rapidly, specifically, and reversibly. Curcumin, demethoxycurcumin, and bisdemethoxycurcumin each bound iron-NTA-agarose with comparable affinities and a stoichiometry near 1. Analyses of binding efficiencies and purity demonstrated that curcuminoids comprise the primary iron binding compounds recovered from a crude turmeric extract. Competition of curcuminoid binding to the iron resin was used to characterize the metal binding site on curcumin and to detect iron binding by added chelators. Curcumin-Iron-NTA-agarose binding was inhibited by other metals with relative potency: (>90% inhibition) Cu²⁺ ~ Al³⁺ > Zn²⁺ ≥ Ca²⁺ ~ Mg²⁺ ~ Mn²⁺ (<20% inhibition). Binding was also inhibited by pharmaceutical iron chelators (desferoxamine or EDTA) or by higher concentrations of weak iron chelators (citrate or silibinin). Investigation of the physiological effects of iron binding by curcumin revealed that curcumin uptake by cultured cells was reduced >80% by addition of iron to the media; uptake was completely restored by desferoxamine. Ranking of metals by relative potencies for blocking curcumin uptake agreed with their relative potencies in blocking curcumin binding to iron-NTA-agarose. We conclude that curcumin can selectively bind toxic metals including iron in a physiological setting, and propose inhibition of curcumin binding to iron-NTA-agarose for iron chelator screening.

Silence of long noncoding RNA PANDAR switches low-dose curcumin-induced senescence to apoptosis in colorectal cancer cells

Long noncoding RNAs (lncRNAs) are emerging as having multiple roles in cancer progression. However, roles of lncRNAs in chemotherapy for colorectal cancer (CRC) remain unclear. This study investigated the biological functions of lncRNA PANDAR in CRC cells treated with curcumin chemotherapy. Herein, we identified that PANDAR expression was not notably differential in CRC tissues compared with the corresponding normal tissues. Consistently, in vitro experiments revealed that knockdown of PANDAR could not change the proliferation, apoptosis, or senescence of CRC cells. Further analyses showed that low-dose curcumin could induce senescence in CRC cells without affecting cell apoptosis. Moreover, expression of PANDAR was increased in curcumin-treated CRC cells. Furthermore, silencing PANDAR in curcumin-treated cells increased apoptosis and greatly attenuated senescence possibly by stimulating the expression of PUMA. Together, these findings indicate that knockdown of lncRNA PANDAR switches curcumin-induced senescence to apoptosis, which may be potentially valuable in CRC therapy.

The Essential Medicinal Chemistry of Curcumin

Curcumin is a constituent (up to ∼5%) of the traditional medicine known as turmeric. Interest in the therapeutic use of turmeric and the relative ease of isolation of curcuminoids has led to their extensive investigation. Curcumin has recently been classified as both a PAINS (pan-assay interference compounds) and an IMPS (invalid metabolic panaceas) candidate. The likely false activity of curcumin in vitro and in vivo has resulted in >120 clinical trials of curcuminoids against several diseases. No double-blinded, placebo controlled clinical trial of curcumin has been successful. This manuscript reviews the essential medicinal chemistry of curcumin and provides evidence that curcumin is an unstable, reactive, nonbioavailable compound and, therefore, a highly improbable lead. On the basis of this in-depth evaluation, potential new directions for research on curcuminoids are discussed.

Highly bioavailable micellar curcuminoids accumulate in blood, are safe and do not reduce blood lipids and inflammation markers in moderately hyperlipidemic individuals

SCOPE

Curcuminoids are poorly bioavailable, but potentially lipid- and inflammation-lowering phytochemicals. We hypothesized that curcuminoids, when administered as a micellar formulation with hundredfold enhanced bioavailability, decrease blood lipids and inflammation in subjects with moderately elevated cholesterol and C-reactive protein concentrations.

METHODS AND RESULTS

We carried out a randomized, double-blind, crossover study (4-wk washout phase) with 42 subjects consuming 294 mg curcuminoids per day (as micelles) or placebo for 6 wk. At the beginning, after 3 wk and at the end (6 wk) of each intervention, we collected fasting blood samples to determine curcuminoids, blood lipids, and markers of inflammation, glucose and iron homeostasis, and liver toxicity. Daily ingestion of 98 mg micellar curcuminoids with each principal meal for as little as 3 wk resulted in fasting curcuminoid plasma concentrations of 49 nmol/L. Neither blood lipids, nor markers of inflammation, glucose and iron homeostasis, or liver enzymes differed between curcuminoid and placebo interventions.

CONCLUSION

Consumption of 98 mg of highly bioavailable curcuminoids with each principal meal sufficed to achieve curcuminoid accumulation in the blood, was safe, and did not alter blood lipids, inflammation, glucose, or iron homeostasis in healthy subjects with slightly elevated blood cholesterol and C-reactive protein.

Tucum-Do-Cerrado (Bactris setosa Mart.) Consumption Modulates Iron Homeostasis and Prevents Iron-Induced Oxidative Stress in the Rat Liver

This study investigated the effect of tucum-do-cerrado consumption in the oxidative status of iron-supplemented rats. Four groups of rats were treated: Control (AIN-93G), Tuc (AIN-93G added of tucum-do-cerrado), Fe (AIN-93G iron-enriched), or TucFe (AIN-93G with tucum-do-cerrado and iron-enriched) diet, for 30 days. Iron-enriched diet increased serum, liver, spleen, and intestine iron levels; transferrin saturation; liver lipid oxidation; mRNA levels of hepatic Hamp and Bmp6, and Nrf2 in the intestine. Tucum-do-cerrado consumption reduced spleen lipid and protein oxidation; mRNA levels of hepatic Hamp and Ftl, and increased serum antioxidant capacity and hepatic mRNA levels of Bmp6, Hmox1, Nqo1, and Nrf2. TucFe diet consumption abrogated the liver Hamp iron-induced up-regulation, prevented intestinal iron accumulation; hepatic lipid peroxidation; splenic protein damage, and the increase of catalase, glutathione reductase, and glutathione peroxidase activity in some tissues. These results suggest that tucum-do-cerrado protects tissues against oxidative damage, by reducing iron availability in liver and consequently inhibiting liver Hamp expression.

Modulation of hepcidin to treat iron deregulation: potential clinical applications

The secreted peptide hormone hepcidin regulates systemic and local iron homeostasis through degradation of the iron exporter ferroportin. Dysregulation of hepcidin leads to altered iron homeostasis and development of pathological disorders including hemochromatosis, and iron loading and iron restrictive anemias. Therapeutic modulation of hepcidin is a promising method to ameliorate these conditions. Several approaches have been taken to enhance or reduce the effects of hepcidin in vitro and in vivo. Based on these approaches, hepcidin modulating drugs have been developed and are undergoing clinical evaluation. In this article we review the rationale for development of these drugs, the data concerning their safety and efficacy, their therapeutic uses, and potential future prospects.

Phytochelators Intended for Clinical Use in Iron Overload, Other Diseases of Iron Imbalance and Free Radical Pathology

Iron chelating drugs are primarily and widely used in the treatment of transfusional iron overload in thalassaemia and similar conditions. Recent in vivo and clinical studies have also shown that chelators, and in particular deferiprone, can be used effectively in many conditions involving free radical damage and pathology including neurodegenerative, renal, hepatic, cardiac conditions and cancer. Many classes of phytochelators (Greek: phyto (φυτό)—plant, chele (χηλή)—claw of the crab) with differing chelating properties, including plant polyphenols resembling chelating drugs, can be developed for clinical use. The phytochelators mimosine and tropolone have been identified to be orally active and effective in animal models for the treatment of iron overload and maltol for the treatment of iron deficiency anaemia. Many critical parameters are required for the development of phytochelators for clinical use including the characterization of the therapeutic targets, ADMET, identification of the therapeutic index and risk/benefit assessment by comparison to existing therapies. Phytochelators can be developed and used as main, alternative or adjuvant therapies including combination therapies with synthetic chelators for synergistic and or complimentary therapeutic effects. The development of phytochelators is a challenging area for the introduction of new pharmaceuticals which can be used in many diseases and also in ageing. The commercial and other considerations for such development have great advantages in comparison to synthetic drugs and could also benefit millions of patients in developing countries.

Adenosine triphosphate concentrations are higher in the brain of APOE3- compared to APOE4-targeted replacement mice and can be modulated by curcumin

Curcumin from Curcuma longa may exert putative neuroprotective properties in the brain. Impaired mitochondrial function is implicated in Alzheimer's disease and the presence of the apolipoprotein (APO) E4 genotype, which is a risk factor for late-onset Alzheimer's disease, may aggravate mitochondrial malfunction. Here, we report that in the brain of 16-month-old APOE4-targeted replacement mice, adenosine triphosphate (ATP) concentrations were significantly lower than in APOE3 mice. A 3-month dietary supplementation of 0.2 % curcumin numerically increased ATP concentrations in APOE3 and significantly in APOE4 mice compared to the respective controls. Curcumin significantly induced the transcription of peroxisome proliferator-activated receptor (PPAR) γ and mitochondrial transcription factor A (TFAM) in APOE3, but not in APOE4 mice. Moreover, PPARγ coactivator (PGC)-1α and guanine-adenine repeat binding protein α (GABPa) mRNA was only increased in APOE3 mice. Consistent with these observations, protein expression of mitochondrial respiratory complexes, especially of complex IV, also appeared to be increased in APOE3 mice. In conclusion, we provide evidence that curcumin affects mitochondrial function and gene and protein expression in the murine brain despite its low bioavailability and carriers of the Alzheimer's disease-risk genotype APOE4 may be less responsive to dietary curcumin than APOE3 carriers.