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Turmeric, a spice that has long been recognized for its medicinal properties, has received interest from both the medical/scientific world and from culinary enthusiasts, as it is the major source of the polyphenol curcumin. It aids in the management of oxidative and inflammatory conditions, metabolic syndrome, arthritis, anxiety, and hyperlipidemia. It may also help in the management of exercise-induced inflammation and muscle soreness, thus enhancing recovery and performance in active people. In addition, a relatively low dose of the complex can provide health benefits for people that do not have diagnosed health conditions. Most of these benefits can be attributed to its antioxidant and anti-inflammatory effects. Ingesting curcumin by itself does not lead to the associated health benefits due to its poor bioavailability, which appears to be primarily due to poor absorption, rapid metabolism, and rapid elimination. There are several components that can increase bioavailability. For example, piperine is the major active component of black pepper and, when combined in a complex with curcumin, has been shown to increase bioavailability by 2000%. Curcumin combined with enhancing agents provides multiple health benefits. The purpose of this review is to provide a brief overview of the plethora of research regarding the health benefits of curcumin.
Curcumin: A Review of Its’ Effects on Human Health
Susan J. Hewlings 1, *ID and Douglas S. Kalman 2
1Department of Nutrition, Central Michigan University Mount Pleasant, MI, USA and Substantiation
Sciences Weston, FL 33143, USA
2Health and Human Performance, Nova Southeastern University and Nutrition Research Division, QPS,
Miami, FL 33143, USA;
*Correspondence:; Tel.: +1-321-377-4522
Received: 2 September 2017; Accepted: 20 October 2017; Published: 22 October 2017
Turmeric, a spice that has long been recognized for its medicinal properties, has received
interest from both the medical/scientific world and from culinary enthusiasts, as it is the major
source of the polyphenol curcumin. It aids in the management of oxidative and inflammatory
conditions, metabolic syndrome, arthritis, anxiety, and hyperlipidemia. It may also help in the
management of exercise-induced inflammation and muscle soreness, thus enhancing recovery and
performance in active people. In addition, a relatively low dose of the complex can provide health
benefits for people that do not have diagnosed health conditions. Most of these benefits can be
attributed to its antioxidant and anti-inflammatory effects. Ingesting curcumin by itself does not lead
to the associated health benefits due to its poor bioavailability, which appears to be primarily due
to poor absorption, rapid metabolism, and rapid elimination. There are several components that
can increase bioavailability. For example, piperine is the major active component of black pepper
and, when combined in a complex with curcumin, has been shown to increase bioavailability by
2000%. Curcumin combined with enhancing agents provides multiple health benefits. The purpose
of this review is to provide a brief overview of the plethora of research regarding the health benefits
of curcumin.
Keywords: curcumin; turmeric; antioxidant; anti-inflammatory; polyphenol
1. Introduction
Turmeric is a spice that has received much interest from both the medical/scientific worlds as
well as from the culinary world. Turmeric is a rhizomatous herbaceous perennial plant (Curcuma longa)
of the ginger family [
]. The medicinal properties of turmeric, the source of curcumin, have been
known for thousands of years; however, the ability to determine the exact mechanism(s) of action
and to determine the bioactive components have only recently been investigated [
]. Curcumin
(1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione), also called diferuloylmethane, is
the main natural polyphenol found in the rhizome of Curcuma longa (turmeric) and in others
Curcuma spp. [
]. Curcuma longa has been traditionally used in Asian countries as a medical herb
due to its antioxidant, anti-inflammatory [
], antimutagenic, antimicrobial [
], and anticancer
properties [7,8].
Curcumin, a polyphenol, has been shown to target multiple signaling molecules while also
demonstrating activity at the cellular level, which has helped to support its multiple health benefits [
It has been shown to benefit inflammatory conditions [
], metabolic syndrome [
], pain [
], and to
help in the management of inflammatory and degenerative eye conditions [
]. In addition, it has
been shown to benefit the kidneys [
]. While there appear to be countless therapeutic benefits to
curcumin supplementation, most of these benefits are due to its antioxidant and anti-inflammatory
effects [
]. Despite its reported benefits via inflammatory and antioxidant mechanisms, one of the
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major problems with ingesting curcumin by itself is its poor bioavailability [
], which appears to
be primarily due to poor absorption, rapid metabolism, and rapid elimination. Several agents have
been tested to improve curcumin’s bioavailability by addressing these various mechanisms. Most
of them have been developed to block the metabolic pathway of curcumin in order to increase its
bioavailability. For example, piperine, a known bioavailability enhancer, is the major active component
of black pepper [
] and is associated with an increase of 2000% in the bioavailability of curcumin [
Therefore, the issue of poor bioavailability appears to be resolved by adding agents such as piperine
that enhance bioavailability, thus creating a curcumin complex.
Curcumin is being recognized and used worldwide in many different forms for multiple potential
health benefits. For example, in India, turmeric—containing curcumin—has been used in curries; in
Japan, it is served in tea; in Thailand, it is used in cosmetics; in China, it is used as a colorant; in Korea, it
is served in drinks; in Malaysia, it is used as an antiseptic; in Pakistan, it is used as an anti-inflammatory
agent; and in the United States, it is used in mustard sauce, cheese, butter, and chips, as a preservative
and a coloring agent, in addition to capsules and powder forms. Curcumin is available in several
forms including capsules, tablets, ointments, energy drinks, soaps, and cosmetics [
]. Curcuminoids
have been approved by the US Food and Drug Administration (FDA) as “Generally Recognized As
Safe” (GRAS) [
], and good tolerability and safety profiles have been shown by clinical trials, even at
doses between 4000 and 8000 mg/day [
] and of doses up to 12,000 mg/day of 95% concentration of
three curcuminoids: curcumin, bisdemethoxycurcumin, and demethoxycurcumin [19].
It is the purpose of this review to provide a brief overview of the plethora of research regarding
the potential health benefits of curcumin. Due to the extent of the literature, we have chosen to focus on
the benefits associated with some common health conditions and on benefits in healthy people rather
than to review the extensive literature related to cancer and other disease states. For a comprehensive
review of curcumin’s effects on cancer, please see the paper by Kunnumakkara et al. 2017 [20].
2. Mechanisms of Action
2.1. Antioxidant
Antioxidant and anti-inflammatory properties are the two primary mechanisms that explain
the majority of the effects of curcumin on the various conditions discussed in this review [
Curcumin has been shown to improve systemic markers of oxidative stress [
]. There is evidence
that it can increase serum activities of antioxidants such as superoxide dismutase (SOD) [
A recent systematic review and meta-analysis of randomized control data related to the efficacy of
supplementation with purified curcuminoids on oxidative stress parameters—indicated a significant
effect of curcuminoids supplementation on all investigated parameters of oxidative stress including
plasma activities of SOD and catalase, as well as serum concentrations of glutathione peroxidase
(GSH) and lipid peroxides [
]. It is noteworthy to point out that all of the studies included in the
meta-analysis utilized some sort of formulation to overcome bioavailability challenges, and four
out of the six used piperine. Curcumin’s effect on free radicals is carried out by several different
mechanisms. It can scavenge different forms of free radicals, such as reactive oxygen and nitrogen
species (ROS and RNS, respectively) [
]; it can modulate the activity of GSH, catalase, and SOD
enzymes active in the neutralization of free radicals [
]; also, it can inhibit ROS-generating enzymes
such as lipoxygenase/cyclooxygenase and xanthine hydrogenase/oxidase [
]. In addition, curcumin
is a lipophilic compound, which makes it an efficient scavenger of peroxyl radicals, therefore, like
vitamin E, curcumin is also considered as a chain-breaking antioxidant [27].
2.2. Anti-Inflammatory
Oxidative stress has been implicated in many chronic diseases, and its pathological processes are
closely related to those of inflammation, in that one can be easily induced by another. In fact, it is known
that inflammatory cells liberate a number of reactive species at the site of inflammation leading to
Foods 2017,6, 92 3 of 11
oxidative stress, which demonstrates the relationship between oxidative stress and inflammation [
In addition, a number of reactive oxygen/nitrogen species can initiate an intracellular signaling cascade
that enhances pro-inflammatory gene expression. Inflammation has been identified in the development
of many chronic diseases and conditions [
]. These diseases include Alzheimer ’s disease
(AD), Parkinson’s disease, multiple sclerosis, epilepsy, cerebral injury, cardiovascular disease, metabolic
syndrome, cancer, allergy, asthma, bronchitis, colitis, arthritis, renal ischemia, psoriasis, diabetes,
obesity, depression, fatigue, and acquired immune deficiency syndromeAIDS [
]. Tumor necrosis
) is a major mediator of inflammation in most diseases, and this effect is regulated by the
activation of a transcription factor, nuclear factor (NF)-
B. Whereas TNF-
is said to be the most potent
B activator, the expression of TNF-
is also regulated by NF-
B. In addition to TNF-
, NF-
is also activated by most inflammatory cytokines; gram-negative bacteria; various disease-causing
viruses; environmental pollutants; chemical, physical, mechanical, and psychological stress; high
glucose; fatty acids; ultraviolet radiation; cigarette smoke; and other disease-causing factors. Therefore,
agents that downregulate NF-
B and NF-
B–regulated gene products have potential efficacy against
several of these diseases. Curcumin has been shown to block NF-
B activation increased by several
different inflammatory stimuli [
]. Curcumin has also been shown to suppress inflammation through
many different mechanisms beyond the scope of this review, thereby supporting its mechanism of
action as a potential anti-inflammatory agent [10].
3. Arthritis
One such disease associated with inflammation, both chronic and acute, is osteoarthritis (OA), a
chronic joint condition. It affects over 250 million people worldwide, leading to increased healthcare
costs, impairment in activities of daily living (ADL), and ultimately decreased quality of life [
Although OA was once considered primarily a degenerative and non-inflammatory condition, it
is now recognized as having inflammatory aspects, including elevated cytokine levels, as well as
potentially being connected with systemic inflammation [
]. While there is no cure, there are
several pharmaceutical options for treatment; however, many are costly and have undesirable side
effects. Therefore, there is increased interest in alternative treatments including dietary supplements
and herbal remedies [
]. Several studies have shown the anti-arthritic effects of curcumin in humans
with OA and rheumatoid arthritis (RA) [
]. In a randomized double-blind placebo-controlled
trial, 40 subjects with mild-to-moderate degree knee OA were randomly assigned to receive either
curcuminoid (500 mg/day in three divided doses; n= 19) with 5 mg piperine added to each 500-mg
dose or a matched placebo (n= 21) for six weeks. There were significantly greater reductions in the
visual analog scale (VAS) (p< 0.001), Western Ontario and McMaster Universities Osteoarthritis Index
(WOMAC) scores (p= 0.001), and Lequesne’s pain functional index (LPFI) (p= 0.013) scores in the
treatment group compared with the placebo group. When comparing the WOMAC subscales, there
were significant improvements in the pain and physical function scores (p< 0.001), but not in the
stiffness score [
]. There was also a decrease in systemic oxidative stress, as measured via serum
activities of SOD and concentrations of reduced GSH and malonedialdehyde (MDA), in subjects
receiving the treatment as compared to the placebo [
]. These improvements were not associated with
changes in circulating cytokines. The authors suggest that the lack of changes in circulating cytokines,
despite improvements in pain, may be because in OA, inflammatory markers in the synovial fluid may
be more likely elevated than systemic markers, whereas in RA, systemic markers may be more likely to
be increased. Therefore, they suggest that is more plausible that the beneficial effects of curcuminoids
in OA are because of local anti-inflammatory effects rather than systemic effects. In addition, the time
period of supplementation may not have been long enough. In a longer (eight months) randomized
control trial, 50 subjects diagnosed with OA were assigned to receive either standard treatment
as prescribed by their physician or standard treatment plus two 500-mg tablets daily consisting of
a natural curcuminoid mixture (20%), containing phosphatidyl-choline (40%) and microcrystalline
cellulose (40%). WOMAC, physical function, and stiffness scores decreased significantly (p< 0.05) in the
Foods 2017,6, 92 4 of 11
treatment group compared to the control. In addition, the treatment group showed significant decreases
in all markers of inflammation (soluble CD40 ligand(sCD40L), interleukin 1 beta (IL-1
), interleukin 6
(IL-6), soluble vascular cell adhesion molecule 1 (sVCAM-1), and erythrocyte sedimentation rate (ESR)
comparing baseline to follow-up, while the control group did not [
]. This study had both groups
maintaining standard care, which does not address the question of whether or not supplementation
with curcumin can be used instead of standard management such as nonsteroidal anti-inflammatory
drugs (NSAIDS). To address this question, 367 primary knee osteoarthritis patients with a pain score of
5 or higher were randomized to receive ibuprofen 1200 mg/day or C. domestica extracts 1500 mg/day
for four weeks. The mean of all WOMAC scores at weeks 0, 2, and 4 showed significant improvement
when compared with the baseline in both groups. After using the noninferiority test, the mean
difference (95% confidence interval) of WOMAC total, WOMAC pain, and WOMAC function scores at
week 4 adjusted by values at week 0 of C. domestica extracts were non-inferior to those for the ibuprofen
group (p= 0.010, p= 0.018, and p= 0.010, respectively), indicating that those taking the curcumin and
those taking the ibuprofen experienced the same benefits. The group taking the NSAIDS did experience
more gastrointestinal issues. This suggests that curcumin may offer an alternative to NSAIDS for
patients with OA seeking treatment but experiencing negative side effects [
]. This was supported by
results from a pilot study showing that a dose of 2 g of curcumin had an analgesic effect in subjects with
acute pain but without a diagnosis of OA. At this dose, the activity was higher than that associated
with 500 mg of acetaminophen, while a lower dose (1.5 g, 300 mg of curcumin) gave only transient
and often inadequate relief of pain, indicative of suboptimal therapeutic plasma concentrations. The
analgesic effect of the dose achieved significance only 2 h after administration, similar to that observed
for acetaminophen. In contrast, the NSAID was more rapidly acting, with the strongest pain relief
being reported one hour after administration but with significant gastrointestinalsymptoms. This
supports the use of 2 g (higher than needed for inflammation) curcumin for relief of pain as a potential
alternative to NSAIDS [41].
Regardless of the mechanism by which curcumin elicits its effects, it does appear to be beneficial
to several aspects of OA, as suggested by a recent systematic review and meta-analysis that concluded:
“This systematic review and meta-analysis provided scientific evidence that 8–12 weeks of standardized
turmeric extracts (typically 1000 mg/day of curcumin) treatment can reduce arthritis symptoms (mainly
pain and inflammation-related symptoms) and result in similar improvements in the symptoms as
ibuprofen and diclofenac sodium. Therefore, turmeric extracts and curcumin can be recommended for
alleviating the symptoms of arthritis, especially osteoarthritis” [42].
4. Metabolic Syndrome
The idea that curcumin can attenuate systemic inflammation has implications beyond arthritis,
as systemic inflammation has been associated with many conditions affecting many systems. One
such condition is Metabolic syndrome (MetS), which includes insulin resistance, hyperglycemia,
hypertension, low high-density lipoprotein cholesterol (HDL-C), elevated low-density lipoprotein
cholesterol (LDL-C), elevated triglyceride levels, and obesity, especially visceral obesity. Curcumin has
been shown to attenuate several aspects of MetS by improving insulin sensitivity [
], suppressing
adipogenesis [
], and reducing elevated blood pressure [
], inflammation [
], and oxidative
stress [
]. In addition, there is evidence that curcuminoids modulate the expression of genes
and the activity of enzymes involved in lipoprotein metabolism that lead to a reduction in plasma
triglycerides and cholesterol [
] and elevate HDL-C concentrations [
]. Both overweight and
obesity are linked to chronic low-grade inflammation; although the exact mechanisms are not
clear, it is known that pro-inflammatory cytokines are released. These cytokines are thought to
be at the core of the complications associated with diabetes and cardiovascular disease. Therefore,
addressing inflammation is important. In a randomized double-blind placebo-controlled trial with
a parallel-group design, 117 subjects with MetS received either 1 g curcumin plus 10 mg piperine
to increase absorption or a placebo plus 10 mg piperine for eight weeks. Within-group analysis
Foods 2017,6, 92 5 of 11
revealed significant reductions in serum concentrations of TNF-
, IL-6, transforming growth factor
beta (TGF-b), and monocyte chemoattractant protein-1 ( MCP-1) following curcumin supplementation
(p< 0.001). In the placebo group, serum levels of TGF-b were decreased (p= 0.003) but those of
IL-6 (p= 0.735), TNF-
(p= 0.138), and MCP-1 (p= 0.832) were not. Between-group comparison
suggested significantly greater reductions in serum concentrations of TNF-
, IL-6, TGF-b, and MCP-1
in the curcumin versus the placebo group (p< 0.001). Apart from IL-6, changes in other parameters
remained statistically significant after adjustment for potential confounders, including changes in
serum lipids and glucose levels, as well as the baseline serum concentration of the cytokines. The results
of this study suggest that curcumin supplementation significantly decreases serum concentrations
of pro-inflammatory cytokines in subjects with MetS [
]. In addition, the study looked at the
cholesterol-lowering properties and found that curcuminoids were more effective than the placebo
in reducing serum LDL-C, non-HDL-C, total cholesterol, triglycerides, and lipoprotein a (Lp(a)), in
addition to elevating HDL-C concentrations. However, changes in serum LDL-C levels were found to
be comparable between the study groups. The effects of curcuminoids on triglycerides, non-HDL-C,
total cholesterol, and Lp(a) remained significant after adjustment for baseline values of lipids and body
mass index [
]. From the same study, the authors also reported markers of oxidative stress. There
was a significant improvement in serum SOD activities (p< 0.001) and reduced MDA (p< 0.001) and
C-reactive protein (CRP) (p< 0.001) concentrations in the group receiving the curcumin with piperine
compared to the placebo group. Their secondary purpose was to perform a meta-analysis of data from
all randomized controlled trials in order to estimate the effect size of curcuminoids on plasma CRP
concentrations. Quantitative data synthesis revealed a significant effect of curcuminoids vs. placebo
in reducing circulating CRP concentrations The authors concluded that short-term supplementation
with a curcuminoid-piperine combination significantly improves oxidative and inflammatory status
in patients with MetS. Curcuminoids could therefore be regarded as natural, safe, and effective
CRP-lowering agents [55].
Inflammatory cytokines were also measured in the above study. Mean serum IL-1
(p= 0.042),
IL-4 (p= 0.008), and vascular endothelial growth factor (VEGF) (p= 0.01) were found to be significantly
reduced by curcumin therapy. In contrast, no significant difference was observed in the concentrations
of IL-2, IL-6, IL-8, IL-10, interferon gamma(IFN
), epidermal growth factor (EGF), and MCP-1. The
authors suggest that the findings indicate that curcumin may exert immunomodulatory effects via
altering the circulating concentrations of IL-1β, IL-4, and VEGF [56].
In a randomized double-blind placebo-controlled crossover trial, 36 obese adults received either
1 g curcumin and 10 mg piperine or a placebo for 30 days followed by a two-week washout period, after
which they received the other treatment. A significant reduction in serum triglyceride concentrations
was observed, but the treatment did not have a significant influence on serum total cholesterol, LDL-C,
HDL-C, and high-sensitivity C-reactive protein (hs-CRP) concentrations, nor on body mass index
(BMI) and body fat. The authors suggest that the short supplemental period, lack of control of diet,
and the low supplemental dose may explain why these results conflict previous reports [50].
5. Healthy People
To date, the majority of curcumin studies in humans have been in populations with existing
health problems. Perhaps this is because studies on healthy people can be challenging in that benefits
may not be as immediate and measurable if biomarkers are normal at baseline. Therefore, following
subjects over time may provide the best insight into any potential health benefits in healthy people,
although such studies can be time-consuming and costly. Making cross-comparisons between the
few studies that have been done can be difficult because studies have used varying doses, often as
high as 1 g [
]. It should be noted that this would be considered a high dose only because it
is higher than what most people could obtain from consuming the spice itself [
]. One study on
healthy adults aged 40–60 years used an 80 mg/day dose of a lipidated form of curcumin. Subjects
were given either curcumin (N= 19) or a placebo (N= 19) for four weeks. The treatment was 400 mg
Foods 2017,6, 92 6 of 11
powder per day containing 80 mg curcumin. Blood and saliva were taken before and after the four
weeks. Curcumin significantly lowered triglyceride levels but not total cholesterol, LDL, or HDL levels.
There was a significant increase in nitrous oxide (NO) and in soluble intercellular adhesion molecule
1 (sICAM), a molecule linked to atherosclerosis. Inflammation-related neutrophil function increased,
as measured by myeloperoxidase concentration, but c-reactive protein and ceruloplasmin did not.
There was a decrease in salivary amylase activity, which can be a marker of stress, and an increase
in salivary radical scavenging capacities and plasma antioxidant enzyme catalase, but not in super
oxide dismutase or glutathione peroxidase. In addition, there was a decrease in beta amyloid plaque, a
marker of brain aging, and in plasma alanine amino transferase activities, a marker of liver injury. This
indicates that a relatively low dose of curcumin can provide health benefits for people that do not have
diagnosed health conditions [51].
In a randomized double-blind placebo-controlled trial, the acute (1 and 3 h after a single
dose), chronic (four weeks), and acute-on-chronic (1 and 3 h after single dose following chronic
treatment) effects of solid lipid curcumin formulation on cognitive function, mood, and blood
biomarkers in 60 healthy adults aged 60–85 years were examined. The curcumin formulation was
400 mg, approximately 80 mg curcumin in a solid lipid formulation with the remaining weight
comprised of commonly used pharmaceutical excipients and small amounts of other curcuminoids
present in turmeric extract. One hour after administration, curcumin significantly improved
performance on sustained attention and working memory tasks, compared with the placebo. Working
memory and mood (general fatigue and change in state calmness, contentedness, and fatigue
induced by psychological stress) were significantly better following chronic treatment. A significant
acute-on-chronic treatment effect on alertness and contentedness was also observed. Curcumin was
associated with significantly reduced total and LDL cholesterol [59].
Another study examined whether supplementation with curcumin and Boswellia serrata (BSE)
gum resin for three months could affect plasma levels of markers of oxidative stress, inflammation, and
glycation in 47 male healthy master cyclists. All subjects were instructed to follow a Mediterranean
diet with 22 subjects receiving a placebo and 25 receiving 50 mg of turmeric, corresponding to 10 mg
of curcumin, as well as 140 mg of Boswellia extract, corresponding to 105 mg of Boswellia acid for
12 weeks. There was a positive effect observed on glycoxidation and lipid peroxidation in healthy
male master athletes [
]. This study indicates the potential for combining curcumin with other agents
to achieve health benefits.
Perhaps another challenge to interpreting studies on healthy people is determining the definition
of healthy, especially when considering that people who do not have an official diagnosis may still
participate in activities or experience situations whereby they challenge their daily physiological
homeostasis. For example, an exercise routine that one is not used to can cause inflammation, oxidative
challenges, and resulting soreness. In a recent study, 28 healthy subjects that did not participate
in resistance training were randomly assigned to receive either curcumin (400 mg/day) for two
days before and four days after participating in an eccentric exercise designed to induce muscle
soreness. Curcumin supplementation resulted in significantly smaller increases in creatine kinase (CK)
48%), TNF-
25%), and IL-8 (
21%) following exercise compared to the placebo. No significant
differences in IL-6, IL-10, or quadriceps muscle soreness between conditions were observed. The
findings demonstrated that the consumption of curcumin reduced biological inflammation, but not
subjective quadriceps muscle soreness during recovery from exercise. This may help to decrease
recovery time, thus improving performance during subsequent exercise sessions [61].
In a similar randomized placebo-controlled single-blind pilot trial, 20 male healthy, moderately
active volunteers were randomized to receive either 1 g curcumin twice daily (200 mg curcumin twice
a day ) or a placebo 48 h prior to and 24 h after a downhill running test. Subjects in the curcumin
group reported significantly less pain in the right and left anterior thigh. Significantly fewer subjects
in the curcumin group had MRI evidence of muscle injury in the posterior or medial compartment
of both thighs. Increases in markers of muscle damage and inflammation tended to be lower in the
Foods 2017,6, 92 7 of 11
curcumin group, but significant differences were only observed for interleukin-8 at 2 h after exercise.
No differences in markers of oxidative stress and muscle histology were observed. These results further
support that curcumin may be beneficial to attenuate exercise-induced muscle soreness (DOMS) [62].
A study by Delecroix et al. offers further support. They reported that 2 g of curcumin and 20 g of
piperine supplementation can help offset some of the physiological markers of muscle soreness after
an intense workout in elite rugby players [63].
In addition to acute physical stresses, humans may also suffer from periods of anxiety or
depression which are sub clinical, but may still benefit from treatments that can decrease the symptoms.
In a randomized double blind cross-over trial, 30 obese adults received curcuminoids (1 g/day) or
a placebo for 30 days, and then after a two-week washout period, crossed over to the alternate
regimen. The curcumin was a 500-mg C3 Complex
(standardized powder extract obtained from
Alleppey finger turmeric containing a minimum 95% concentration of three curcuminoids: curcumin,
bisdemethoxycurcumin, and demethoxycurcumin) plus 5 mg bioperine
per serving to enhance
absorption. Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI) scales were filled out
for each participant at baseline and after four, six, and 10 weeks of supplementation. Mean BAI score
was found to be significantly reduced following curcumin therapy (p= 0.03). However, curcumin
supplementation did not exert any significant impact on BDI scores. This study suggests that curcumin
has a potential anti-anxiety effect in otherwise healthy obese people [64].
6. Side Effects
Curcumin has a long established safety record. For example, according to JECFA (The Joint
United Nations and World Health Organization Expert Committee on Food Additives) and EFSA
(European Food Safety Authority) reports, the Allowable Daily Intake (ADI) value of curcumin is
0–3 mg/kg body weight [
]. Several trials on healthy subjects have supported the safety and efficacy
of curcumin. Despite this well-established safety, some negative side effects have been reported. Seven
subjects receiving 500–12,000 mg in a dose response study and followed for 72 h experienced diarrhea,
headache, rash, and yellow stool [
]. In another study, some subjects receiving 0.45 to 3.6 g/day
curcumin for one to four months reported nausea and diarrhea and an increase in serum alkaline
phosphatase and lactate dehydrogenase contents [66].
7. Conclusions
Curcumin has received worldwide attention for its multiple health benefits, which appear to act
primarily through its anti-oxidant and anti-inflammatory mechanisms. These benefits are best achieved
when curcumin is combined with agents such as piperine, which increase its bioavailability significantly.
Research suggests that curcumin can help in the management of oxidative and inflammatory conditions,
metabolic syndrome, arthritis, anxiety, and hyperlipidemia. It may also help in the management
of exercise-induced inflammation and muscle soreness, thus enhancing recovery and subsequent
performance in active people. In addition, a relatively low dose can provide health benefits for people
that do not have diagnosed health conditions.
Author Contributions:
Susan J. Hewlings and Douglas S. Kalman equally contributed to the background research,
writing, and reviewing of this manuscript.
Conflicts of Interest: The authors declare no conflict of interest.
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... Similarly, the combination of nanocurcumin and CoQ10 synergistically reduced the frequency, severity, and duration of migraine attacks (Parohan et al., 2019). ICAM-1 is a proinflammatory factor that can lead to the release of inflammatory mediators and TNF-α is a major mediator of inflammation in most diseases/conditions (Hewlings & Kalman, 2017). The ability of nanocurcumin in combination with other therapeutics to impact these factors suggests that they might play a vital role in the alleviation of various diseases or conditions, such as migraine that progress via inflammatory processes. ...
... Nanocurcumin also reduced pain scores, stiffness, and physical activity subscales of patients with knee osteoarthritis compared to the control group that received placebo capsules (Hashemzadeh, Davoudian, Jaafari, & Mirfeizi, 2020). Nonsteroidal anti-inflammatory drugs (NSAIDs), such as diclofenac, are standard pain treatments but can result in a range of side effects (Hewlings & Kalman, 2017). The use of natural products can, therefore, be deemed preferential especially given their superior effects when nano-sized. ...
... The use of natural products can, therefore, be deemed preferential especially given their superior effects when nano-sized. This, therefore, means that both ginger extract and curcumin may offer an alternative to NSAIDS for patients with knee osteoarthritis who are experiencing negative side effects from standard treatments (Hewlings & Kalman, 2017). The use of nanocurcumin by patients with rheumatoid arthritis was, however, not as promising as no significant differences were observed between the nanocurcumin and control groups (Javadi, Haghighian, Goodarzy, Abbasi, & Nassiri-Asl, 2019). ...
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A significant percentage of the population has been turning to herbal remedies either as a sole treatment option or in combination with other drugs. Efforts to increase the production of therapeutic remedies from these scaffolds have therefore amplified. A fundamental aim when developing new drugs is to develop drugs that have virtually no or less adverse effects than those currently available while being efficacious. Several approaches have been undertaken to use nanotechnology to develop nanoencapsulated polyphenols for use in therapeutics in an attempt to improve their physicochemical properties, bioavailability, and efficacy. This review covers the types of nanopolyphenols that have been evaluated in clinical trials against various medical conditions and their outcomes. Medical conditions covered include cardiometabolic diseases, inflammatory diseases, and cancer and in almost all instances the nanoencapsulated polyphenol produced a positive outcome. Similar outcomes were also reported for pharmacokinetic analyses. The review protocol was registered in the PROSPERO International Prospective Register of Systematic Reviews as CRD42020172642.
... A major barrier to curcumin's therapeutic efficacy is its low bioavailability and stability owing to its poor absorption, rapid metabolism, and excretion [5,38]. To overcome these limitations, several approaches have been proposed, which include using different doses and forms of curcumin [5,[39][40][41]. Therefore, studies were categorized according to the amount and type of curcumin used: 1000 milligrams (mg) or less of curcumin per day, 1500 mg of curcumin per day, phytosomal form of curcumin, and other forms of curcumin. ...
... Despite its health benefits, curcumin's low bioavailability and stability, due to its poor absorption, rapid metabolism, and elimination, affect its therapeutic efficacy [5,38]. To optimize the health benefits, it is suggested to use a bioavailability enhancer such as piperine [39], phytosomal [40], nano [5], and amorphous curcumin [21,54]. ...
... In addition to the health benefits, curcumin has been also approved as "Generally Recognized as Safe" (GRAS) by the US Food and Drug Administration (FDA) [39,56]. According to the WHO research committee and the European Food Safety Authority (EFSA), as much as 3 mg curcumin per kg body weight can be taken daily [39,57]. ...
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Over the past decades, the worldwide prevalence of obesity has dramatically increased, thus posing a serious public health threat. Obesity is associated with the development of comorbid conditions and psychological disorders. Several lifestyle interventions have been proposed to tackle obesity; however, long-term maintenance of these interventions often proves challenging. In addition, among the different types of diets there is still a debate about the optimal macronutrient composition that will achieve the best results in weight loss. Recently, several commonly used spices such as pepper, ginger, and curcumin have been shown to play a beneficial role in obesity management. Therefore, exploring the effects of certain herbs or dietary spices on obesity may be promising. Among these spices, curcumin, which is the primary component of the spice turmeric, has gained great interest for its multiple health benefits. Several randomized controlled trials have investigated the potential favorable effects of curcumin supplementation on anthropometric measures. The aim of this review is to evaluate the effect of curcumin supplementation on the anthropometric indices among overweight or obese adults.
... It has a time-tested reputation in alleviating symptoms in several neurological disorders. Studies have demonstrated its action on delaying neuropathic pain and specifically benefiting patients with post-chemotherapeutic neuropathies [34,35]. 5. Fish oil, rich in omega-3 fatty acids, is effective in alleviating symptoms of diabetic peripheral neuropathy. ...
... Logically, in a condition such as peripheral neuropathy with multiple components, different nutraceutical agents have various and distinct roles regarding the underlying pathology. Foods rich in antioxidants and vitamins will promote the repair of damaged nerves and help maintain general nerve health [16][17][18]22,23,32,[34][35][36][37]. ...
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According to the International Association of the Study of Pain (IASP), neuropathic pain is caused by a primary lesion or dysfunction of the nervous system. The lesion may be peripheral, spinal, or supra-spinal and is differentiated from other types of pain due to sensory symptoms caused by a compromised peripheral or central nervous system. Neuropathic pain is further delineated as "evoked pain" or "rest pain", the latter typically observed in spinal cord injury patients. Neuropathies can be cranial, autonomic, or focal. The major types and categories of neuropathies include chronic degenerative neuropathy, post-traumatic neuropathy, diabetic neuropathy, stroke-related neuropathy, and peripheral neuropathy. Common comorbidities include Alzheimer's disease and Par-kinson's disease. Neuropathic conditions are diagnosed by a patient's medical history, examination, and when indicated, electromyography (EMG) and the nerve conduction velocity (NCV) test. This research explores non-pharmacologic care and management of specific neuropathies, particularly nutrition, and nutritional supplementation, and photobiomodulation therapy (PBMT), also known as low-level laser therapy (LLLT). Comparisons are given regarding these modalities and conventional treatments. Although research into the efficacious applications of nutrition, nutritional supplements, and photobiomodulation therapy is in its relative infancy, these modalities seem promising when used alone or, in combination and or as conjunctive therapies with conventional treatments.
... Curcumin, also known as turmeric, is a polyphenol derived from curcumin longa, and is traditionally used in various Asian cuisine [20]. Recently, curcumin has been studied to adjunctly treat broad spectrum of disease from type 2 diabetes mellitus to telogen effluvium [21]. ...
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The therapeutic effects of curcumin for polycystic ovary syndrome (PCOS) remain inconclusive. The present study aims to evaluate the effects of curcumin on glycemic control and lipid profile in patients with PCOS. PubMed, Embase, Scopus, Web of Science, and Cochrane Library were searched from the inception through 28 November 2020. Randomized control trials (RCTs), which enrolled adult patients with PCOS, compared curcumin with placebo regarding the glycemic control and lipid profile, and reported sufficient information for performing meta-analysis, were included. Three RCTs were included. Curcumin significantly improves fasting glucose (mean difference (MD): −2.77, 95% confidence interval (CI): −4.16 to −1.38), fasting insulin (MD: −1.33, 95% CI: −2.18 to −0.49), Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) (MD: −0.32, 95% CI: −0.52 to −0.12), and quantitative insulin sensitivity check index (QUICKI) (MD: 0.010, 95% CI: 0.003–0.018). It also significantly improves high-density lipoprotein (MD: 1.92, 95% CI: 0.33–3.51) and total cholesterol (MD: −12.45, 95% CI: −22.05 to −2.85). In contrast, there is no statistically significant difference in the improvement in low-density lipoprotein (MD: −6.02, 95% CI: −26.66 to 14.62) and triglyceride (MD: 8.22, 95% CI: −26.10 to 42.53) between curcumin and placebo. The results of the fasting glucose, fasting insulin, HOMA-IR, QUICKI, and total cholesterol are conclusive as indicated by the trial sequential analysis. Curcumin may improve glycemic control and lipid metabolism in patients with PCOS and metabolic abnormality without significant adverse effects. Further studies are advocated to investigate the potential effects of curcumin on hyperandrogenism.
... Stilbenes, such as resveratrol and pterostilbene, are found in grapes, cranberries and red fruits [96]. In terms of curcuminoids, curcumin stands out originating from rhizome of turmeric [97]. ...
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The relationship between gut microbiota and neurodegenerative diseases is becoming clearer. Among said diseases amyotrophic lateral sclerosis (ALS) stands out due to its severity and, as with other chronic pathologies that cause neurodegeneration, gut microbiota could play a fundamental role in its pathogenesis. Therefore, polyphenols could be a therapeutic alternative due to their anti-inflammatory action and probiotic effect. Thus, the objective of our narrative review was to identify those bacteria that could have connection with the mentioned disease (ALS) and to analyze the benefits produced by administering polyphenols. Therefore, an extensive search was carried out selecting the most relevant articles published between 2005 and 2020 on the PubMed and EBSCO database on research carried out on cell, animal and human models of the disease. Thereby, after selecting, analyzing and debating the main articles on this topic, the bacteria related to the pathogenesis of ALS have been identified, among which we can positively highlight the presence mainly of Akkermansia muciniphila, but also Lactobacillus spp., Bifidobacterium spp. or Butyrivibrio fibrisolvens. Nevertheless, the presence of Escherichia coli or Ruminococcus torques stand out negatively for the disease. In addition, most of these bacteria are associated with molecular changes also linked to the pathogenesis of ALS. However, once the main polyphenols related to improvements in any of these three ALS models were assessed, many of them show positive results that could improve the prognosis of the disease. Nonetheless, epigallocatechin gallate (EGCG), curcumin and resveratrol are the polyphenols considered to show the most promising results as a therapeutic alternative for ALS through changes in microbiota.
... Turmeric is a spice with a wide spectrum of medical and scientific effects. This spice is the powder of the rhizomes perennial plant, Curcuma longa, a plant distributed in South Asia such as China, Japan, South Korea, and is extensively cultivated in India [6,9]. Turmeric has been extensively used as an herbal medicine to treat various health problems such as biliary disorders, liver diseases, anorexia, common cold, diabetic wounds and rheumatism [10]. ...
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Renal ischemia/reperfusion (I/R) injury is considered as a main problem in clinical practice. Curcuminoids, the active constituents of turmeric, seem to have potential renoprotective effects. However, the poor bioavailability of curcuminoids restricts their therapeutic effects. In the present study, the effect of nanomicellar curcuminoids (NC) treatment on renal function, histology, total antioxidant capacity (TAC), total oxidative stress (TOS), caspase-3 level as well as mitogen activated protein kinases (MAPKs: JNK, p38 and ERK) phosphorylation were evaluated following renal I/R. Adult male Sprague–Dawley rats were administered NC at the dose of 25 mg/kg 1 h before renal ischemia induction. The animals were subjected to bilateral renal ischemia for 60 min and reperfusion for 24 h. Subsequently, blood urea nitrogen (BUN), creatinine (Cr), renal histopathology, TAC, TOS, and oxidative stress index, cleaved caspase-3 level, Bax and MAPKs signaling were evaluated. The results indicated that NC pretreatment at the dose of 25 mg/kg significantly improved renal function as well as histolopatholgical damages. Moreover, NC reduced the level of renal oxidative stress, cleaved caspase-3 and Bax (as the proapoptotic proteins) and suppressed the activated Jun N-terminal Kinase (JNK), p38 and extracellular receptor kinase (ERK) signaling induced by renal I/R. The findings of the current study indicate that NC might prevent the injury induced by renal I/R through suppression of oxidative stress, apoptosis and MAPKs pathways.
... Curcumin, the traditional medicine in China and India, is a natural phytochemical ingredient from the root of curcuma [16]. Several lines of evidences indicated that curcumin could treat a wide variety of diseases including diabetes complications, chronic inflammation, hyperlipoidemia, neurodegenerative diseases, amenorrhea, etc. [17]. Meanwhile, curcumin even had low or no toxic side effects [18]. ...
Full-text available
Background Diabetic encephalopathy is a severe diabetes complication with cognitive dysfunction and neuropsychiatric disability. The mechanisms underlying diabetic encephalopathy is believed to be relevant with oxidative stress, vascular amylin deposition, immune receptors, inflammation, etc. This study wanted to evaluate the ability of curcumin and its analog A13 to alleviate oxidative stress and inflammation in diabetes-induced damages in brain. Methods Sixty adult male Sprague–Dawley rats were divided into 5 groups: normal control (NC) group, diabetes mellitus (DM) group, curcumin-treated diabetes mellitus (CUR) group, high dose of A13-treated diabetes mellitus (HA) group, low dose of A13-treated diabetes mellitus (LA) group. Activation of the nuclear factor kappa-B (NF-κB p65) pathway was detected by RT-qPCR, immunohistochemical (IHC) staining and Western blot; oxidative stress was detected by biochemical detection kit; brain tissue sections were stained with hematoxylin–eosin (HE) staining and Myelin staining. Results RT-qPCR, IHC staining and Western blot showed that curcumin and A13 treatment could inhibit the NF-κB p65 pathway. Curcumin and A13 increased the activity of superoxide dismutase and decreased the malondialdehyde level in the brain of diabetic rats. Furthermore, HE staining and Myelin staining demonstrated that the histological lesions of the brain in diabetic rats could be significantly ameliorated by curcumin and A13. Conclusion Curcumin analog A13 could alleviate the damages in the brain of diabetes rats by regulating the pathways of inflammation and oxidative stress. A13 may be a new potential therapeutic agent for diabetic encephalopathy.
... In view of NIH fostering research in alternative medicine, 20 it is worth mentioning two studies of aptamerguided delivery of curcumin (CUR), a natural product derived from the spice turmeric, the health effects of which have been reviewed elsewhere. 21 In the first study, Ma et al. 22 prepared conventional nanoliposomes (NLPs) that were then conjugated to an RNA aptamer, A15, known to bind to CD133, which marks normal prostate epithelial stem cells and rare malignant tumor stem/initiating cells. The NLPs were loaded with CUR to provide A15-CUR-NLPs for which drug burst-release was observed within 2 h, followed by continuous release over 48 h. ...
Full-text available
Aptamers, which are short strands of synthetic DNA or RNA selected for binding to target ligands, have proven useful for cell-specific delivery, detection, or both. This mini-review presents selected examples of these applications for cancer published during 2019 – September 2020.
... Curcumin (CM) (1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6heptadiene-3,5dione) is a polyphenolic compound derived from turmeric, the rhizome of the Curcuma longa plant. 1 This compound has anti-inammatory, anticoagulant, 2 antitumor 3,4 and anti HIV 5 properties. ...
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Curcumin is a polyphenolic compound with anti-oxidative and anti-cancer properties that is obtained from turmeric plants. Several studies have demonstrated that cancer cells are not killed unless they are exposed to 5-50 mM of curcumin. Consequently, it is vital to control the concentration of curcumin in cancer therapy. In this study, a sensitive electrochemical sensor was fabricated based on a beta-cyclodextrin-reduced graphene oxide (b-CD-rGO) nanocomposite for measuring curcumin concentration. The effects of experimental factors were investigated and the optimum parametric conditions were determined using the Taguchi optimization method. The b-CD-rGO modified electrode exhibited good electrochemical properties for curcumin detection. The results of differential pulse voltammetry experiments unveiled that the sensor shows a linear response to curcumin concentration over the range of 0.05-10 mM with a detection limit of 33 nM and sensitivity of 4.813 mA mM À1. The fabricated sensor exhibited selectivity in the presence of other electroactive species, e.g., propranolol, clomipramine and clonazepam.
The development and spread of resistance to antimicrobial drugs is hampering the management of microbial infectious and wound healing processes. Curcumin is the most active and effective constituent of Curcuma longa L., also known as turmeric, and has a very long and strong history of medicinal value for human health and skincare. Curcumin has been proposed as strong antimicrobial potentialities and many attempts have been made to determine its ability to conjointly control bacterial growth and promote wound healing. However, low aqueous solubility, poor tissue absorption and short plasma half-life due its rapid metabolism needs to be solved for made curcumin formulations as suitable treatment for wound healing. New curcumin nanoformulations have been designed to solve the low bioavailability problem of curcumin. Thus, in the present review, the therapeutic applications of curcumin nanoformulations for antimicrobial and wound healing purposes is described.
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Background: Chronic intensive exercise is associated with a greater induction of oxidative stress and with an excess of endogenous advanced glycation end-products (AGEs). Curcumin can reduce the accumulation of AGEs in vitro and in animal models. We examined whether supplementation with curcumin and Boswellia serrata (BSE) gum resin for 3 months could affect plasma levels of markers of oxidative stress, inflammation, and glycation in healthy master cyclists. Methods: Forty-seven healthy male athletes were randomly assigned to Group 1, consisting of 22 subjects given a Mediterranean diet (MD) alone (MD group), and Group 2 consisted of 25 subjects given a MD plus curcumin and BSE (curcumin/BSE group). Interleukin-6 (IL-6), tumor necrosis factor-α (TNFα), high-sensitivity c-reactive protein (hs-CRP), total AGE, soluble receptor for AGE (sRAGE), malondialdehyde (MDA), plasma phospholipid fatty acid (PPFA) composition, and non-esterified fatty acids (NEFA) were tested at baseline and after 12 weeks. Results: sRAGE, NEFA, and MDA decreased significantly in both groups, while only the curcumin/BSE group showed a significant decline in total AGE. Only the changes in total AGE and MDA differed significantly between the curcumin/BSE and MD groups. Conclusions: Our data suggest a positive effect of supplementation with curcumin and BSE on glycoxidation and lipid peroxidation in chronically exercising master athletes.
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Although turmeric and its curcumin-enriched extracts have been used for treating arthritis, no systematic review and meta-analysis of randomized clinical trials (RCTs) have been conducted to evaluate the strength of the research. We systemically evaluated all RCTs of turmeric extracts and curcumin for treating arthritis symptoms to elucidate the efficacy of curcuma for alleviating the symptoms of arthritis. Literature searches were conducted using 12 electronic databases, including PubMed, Embase, Cochrane Library, Korean databases, Chinese medical databases, and Indian scientific database. Search terms used were "turmeric," "curcuma," "curcumin," "arthritis," and "osteoarthritis." A pain visual analogue score (PVAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were used for the major outcomes of arthritis. Initial searches yielded 29 articles, of which 8 met specific selection criteria. Three among the included RCTs reported reduction of PVAS (mean difference: -2.04 [-2.85, -1.24]) with turmeric/curcumin in comparison with placebo (P < .00001), whereas meta-analysis of four studies showed a decrease of WOMAC with turmeric/curcumin treatment (mean difference: -15.36 [-26.9, -3.77]; P = .009). Furthermore, there was no significant mean difference in PVAS between turmeric/curcumin and pain medicine in meta-analysis of five studies. Eight RCTs included in the review exhibited low to moderate risk of bias. There was no publication bias in the meta-analysis. In conclusion, these RCTs provide scientific evidence that supports the efficacy of turmeric extract (about 1000 mg/day of curcumin) in the treatment of arthritis. However, the total number of RCTs included in the analysis, the total sample size, and the methodological quality of the primary studies were not sufficient to draw definitive conclusions. Thus, more rigorous and larger studies are needed to confirm the therapeutic efficacy of turmeric for arthritis.
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Background: Exercise-Induced Muscle Damage (EIMD) and delayed onset muscle soreness (DOMS) impact subsequent training sessions and activities of daily living (ADL) even in active individuals. In sedentary or diseased individuals, EIMD and DOMS may be even more pronounced and present even in the absence of structured exercise. Methods: The purpose of this study was to determine the effects of oral curcumin supplementation (Longvida® 400 mg/days) on muscle & ADL soreness, creatine kinase (CK), and inflammatory cytokines (TNF-α, IL-6, IL-8, IL-10) following EMID (eccentric-only dual-leg press exercise). Subjects (N = 28) were randomly assigned to either curcumin (400 mg/day) or placebo (rice flour) and supplemented 2 days before to 4 days after EMID. Blood samples were collected prior to (PRE), and 1, 2, 3, and 4 days after EIMD to measure CK and inflammatory cytokines. Data were analyzed by ANOVA with P < 0.05. Results: Curcumin supplementation resulted in significantly smaller increases in CK (- 48%), TNF-α (- 25%), and IL-8 (- 21%) following EIMD compared to placebo. We observed no significant differences in IL-6, IL-10, or quadriceps muscle soreness between conditions for this sample size. Conclusions: Collectively, the findings demonstrated that consumption of curcumin reduced biological inflammation, but not quadriceps muscle soreness, during recovery after EIMD. The observed improvements in biological inflammation may translate to faster recovery and improved functional capacity during subsequent exercise sessions. General significance: These findings support the use of oral curcumin supplementation to reduce the symptoms of EIMD. The next logical step is to evaluate further the efficacy of an inflammatory clinical disease model.
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Oxidative stress has been implicated in many chronic diseases. However, antioxidant trials are so far largely unsuccessful as a preventive or curative measure. Chronic low-grade inflammatory process, on the other hand, plays a central role in the pathogenesis of a number of chronic diseases. Oxidative stress and inflammation are closely related pathophysiological processes, one of which can be easily induced by another.Thus, both processes are simultaneously found in many pathological conditions.Therefore, the failure of antioxidant trials might result from failure to select appropriate agents that specifically target both inflammation and oxidative stress or failure to use both antioxidants and anti-inflammatory agents simultaneously or use of nonselective agents that block some of the oxidative and/or inflammatory pathways but exaggerate the others. To examine whether the interdependence between oxidative stress and inflammation can explain the antioxidant paradox we discussed in the present review the basic aspects of oxidative stress and inflammation and their relationship and dependence.
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Turmeric (Curcuma Longa) is a type of herb belonging to ginger family, which is widely grown in southern and south western tropical Asia region. Turmeric, which has an importance place in the cuisines of Iran, Malesia, India, China, Polynesia and Thailand, is often used as spice and has an effect on the nature, color and taste of foods. Turmeric is also known to have been used for centuries in India and China for the medical treatments of such illnesses as dermatologic diseases, infection, stress and depression. Turmeric's effects on health generally are centered upon an orange-yellow colored, lipophilic polyphenol substance called 'curcumin', which is acquired from the rhizomes of the herb. Curcumin is known recently to have antioxidant, anti-inflammatory, anti-cancer effects and, thanks to these effects, to have an important role in prevention and treatment of various illnesses ranging notably from cancer to autoimmune, neurological, cardiovascular diseases and diabetic. Furthermore, it is aimed to increase the biological activity and physiological effects of the curcumin on the body by synthesizing curcumin analogues. This paper reviews the history, chemical and physical features, analogues, metabolites, mechanisms of its physiological activities and effects on health of curcumin.
Curcumin, a component of a spice native to India, was first isolated in 1815 by Vogel and Pelletier from the rhizomes of Curcuma longa (turmeric) and, subsequently, the chemical structure of curcumin as diferuloylmethane was reported by Milobedzka et al. [(1910) 43., 2163-2170].Since then, this polyphenol has been shown to exhibit antioxidant, anti-inflammatory, anticancer, antiviral, antibacterial, and antifungal activities. The current review primarily focuses on the anticancer potential of curcumin through the modulation of multiple cell signaling pathways. Curcumin modulates diverse transcription factors, inflammatory cytokines, enzymes, kinases, growth factors, receptors, and various other proteins with an affinity ranging from the pM to the mM range. Furthermore, curcumin effectively regulates tumor cell growth via modulation of numerous cell signaling pathways and potentiates the effect of chemotherapeutic agents and radiation against cancer. Curcumin can interact with most of the targets that are modulated by FDA-approved drugs for cancer therapy. The focus of this review is to discuss the molecular basis for the anticancer activities of curcumin based on preclinical and clinical findings.
The aim of this study was to analyze the effects of oral consumption of curcumin and piperine in combination on the recovery kinetics after exercise-induced muscle damage. Fortyeight hours before and following exercise-induced muscle damage, ten elite rugby players consumed curcumin and piperine (experimental condition) or placebo. A randomized cross-over design was performed. Concentric and isometric peak torque for the knee extensors, one leg 6 seconds sprint performance on a non-motorized treadmill, counter movement jump performance, blood creatine kinase concentration and muscle soreness were assessed immediately after exercise, then at 24h, 48h and 72h post-exercise. There were moderate to large effects of the exercise on the concentric peak torque for the knee extensors (Effect size (ES) = -1.12; Confidence interval at 90% (CI90%): -2.17 to -0.06), the one leg 6 seconds sprint performance (ES=-1.65; CI90% = -2.51to -0.80) and the counter movement jump performance (ES = -0.56; CI90% = -0.81 to -0.32) in the 48h following the exercise. There was also a large effect of the exercise on the creatine kinase level 72h after the exercise in the control group (ES = 3.61; CI90%: 0.24 to 6.98). This decrease in muscle function and this elevation in creatine kinase indicate that the exercise implemented was efficient to induce muscle damage. Twenty four hours post-exercise, the reduction (from baseline) in sprint mean power output was moderately lower in the experimental condition (-1.77 ± 7.25%; 1277 ± 153W) in comparison with the placebo condition (-13.6 ± 13.0%; 1130 ± 241W) (Effect Size = -1.12; Confidence Interval 90%=-1.86 to -0.86). However, no other effect was found between the two conditions. Curcumin and piperine supplementation before and after exercise can attenuate some, but not all, aspects of muscle damage.
Background: Cytokines are involved in the development of metabolic abnormalities that may result in metabolic syndrome (MetS). Since curcumin has shown anti-inflammatory properties, the aim of this study was to evaluate the effect of curcumin supplementation on serum cytokines concentrations in subjects with MetS. Methods: This study was a post-hoc analysis of a randomized controlled trial in which males and females with diagnosis of MetS, according to the criteria defined by the National Cholesterol Education Program Adult Treatment Panel III guidelines, were studied. Subjects who met the inclusion criteria were randomly assigned to either curcumin (daily dose of 1g/day) or a matched placebo for a period of 8 weeks. Results: One hundred and seventeen subjects were assigned to either curcumin (n=59) or placebo (n=58) groups. Within-group analysis revealed significant reductions in serum concentrations of TNF-α, IL-6, TGF-β and MCP-1 following curcumin supplementation (p<0.001). In the placebo group, serum levels of TGF-β were decreased (p=0.003) but those of IL-6 (p=0.735), TNF-α (p=0.138) and MCP-1 (p=0.832) remained unaltered by the end of study. Between-group comparison suggested significantly greater reductions in serum concentrations of TNF-α, IL-6, TGF-β and MCP-1 in the curcumin versus placebo group (p<0.001). Apart from IL-6, changes in other parameters remained statistically significant after adjustment for potential confounders including changes in serum lipids and glucose levels, and baseline serum concentration of the cytokines. Conclusion: Results of the present study suggest that curcumin supplementation significantly decreases serum concentrations of pro-inflammatory cytokines in subjects with MetS.