An hydroalcoholic extract of curcuma longa lowers the apo B/apo A ratio. Implications for atherogenesis prevention

Recent updates on clinical developments of curcumin and its derivatives

Curcumin, a natural polyphenol, derived from Curcuma longa L. is extensively studied by various researchers across the globe and has established its immense potential in the management of several disorders at clinical level. The underlying mechanism of curcumin involves regulation of various molecular targets, namely, inflammatory cytokines, transcription factor, apoptotic genes, growth factors, oxidative stress biomarkers, and protein kinases. In clinical trials, curcumin as an adjuvant has significantly boost-up the efficacy of many proven drugs in the management of arthritis, neurodegenerative disorder, oral infection, and gastrointestinal disorders. Moreover, clinical studies have suggested curcumin as an appropriate candidate for the prevention and/or management of various cancers via regulation of signaling molecules including NF-kB, cytokines, C-reactive protein, prostaglandin E2, Nrf2, HO-1, ALT, AST, kinases, and blood profiles. This article highlights plethora of clinical trials that have been conducted on curcumin and its derivatives in the management of several ailments. Besides, it provides recent updates to the investigators for conducting future research to fulfill the current gaps to expedite the curcumin utility in clinical subjects bearing different pathological states.

A Review of the Anti-Obesity Effects of Wild Edible Plants in the Mediterranean Diet and Their Active Compounds: From Traditional Uses to Action Mechanisms and Therapeutic Targets

Obesity is a long-term condition resulting from a continuous imbalance between the amount of energy consumed and expended. It is associated with premature mortality and contributes to a large portion of the global chronic disease burden, including diabesity, cardiovascular disease, hypertension, and some cancers. While lifestyle changes and dietary adjustments are the primary ways to manage obesity, they may not always be sufficient for long-term weight loss. In these cases, medication may be necessary. However, the options for drugs are limited due to their potential side effects. As a result, there is a need to identify safe and effective alternative treatments. Recently, dietary compounds, plants, and bioactive phytochemicals have been considered as promising sources for discovering new pharmacological agents to treat obesity and its related complications. These natural products can function independently or synergistically with other plants to augment their effects at various levels of the body. They can modulate appetite, lipase activity, thermogenesis and fat synthesis and degradation, satiation, adipogenesis, and adipocyte apoptosis. Additionally, targeting adipocyte growth and differentiation with diverse medicinal plants/diet is a significant strategy for devising new anti-obesity drugs that can intervene in preadipocytes, maturing preadipocytes, and mature adipocytes. Clinical trials have shown that the wild edible plants in the Mediterranean diet can reduce the risk of obesity and its related diseases. This review examines the effectiveness of the common components of the Mediterranean diet in managing obesity and its associated health issues. We conducted a comprehensive literature review using PubMed, Science Direct, Google Scholar, and Medline Plus to gather data on the therapeutic effects of the Mediterranean diet and phytochemicals in treating obesity and its associated diseases.

The Regulatory Effect of Phytochemicals on Chronic Diseases by Targeting Nrf2-ARE Signaling Pathway

Redox balance is essential to maintain the body's normal metabolism. Once disrupted, it may lead to various chronic diseases, such as diabetes, neurodegenerative diseases, cardiovascular diseases, inflammatory diseases, cancer, aging, etc. Oxidative stress can cause or aggravate a series of pathological processes. Inhibition of oxidative stress and related pathological processes can help to ameliorate these chronic diseases, which have been found to be associated with Nrf2 activation. Nrf2 activation can not only regulate the expression of a series of antioxidant genes that reduce oxidative stress and its damage, but also directly regulate genes related to the above-mentioned pathological processes to counter the corresponding changes. Therefore, targeting Nrf2 has great potential for the prevention or treatment of chronic diseases, and many natural phytochemicals have been reported as Nrf2 activators although the defined mechanisms remain to be elucidated. This review article focuses on the possible mechanism of Nrf2 activation by natural phytochemicals in the prevention or treatment of chronic diseases and the regulation of oxidative stress. Moreover, the current clinical trials of phytochemical-originated drug discovery by targeting the Nrf2-ARE pathway were also summarized; the outcomes or the relationship between phytochemicals and chronic diseases prevention are finally analyzed to propose the future research strategies and prospective.

Alterations of HDL's to piHDL's Proteome in Patients with Chronic Inflammatory Diseases, and HDL-Targeted Therapies

Chronic inflammatory diseases, such as rheumatoid arthritis, steatohepatitis, periodontitis, chronic kidney disease, and others are associated with an increased risk of atherosclerotic cardiovascular disease, which persists even after accounting for traditional cardiac risk factors. The common factor linking these diseases to accelerated atherosclerosis is chronic systemic low-grade inflammation triggering changes in lipoprotein structure and metabolism. HDL, an independent marker of cardiovascular risk, is a lipoprotein particle with numerous important anti-atherogenic properties. Besides the essential role in reverse cholesterol transport, HDL possesses antioxidative, anti-inflammatory, antiapoptotic, and antithrombotic properties. Inflammation and inflammation-associated pathologies can cause modifications in HDL's proteome and lipidome, transforming HDL from atheroprotective into a pro-atherosclerotic lipoprotein. Therefore, a simple increase in HDL concentration in patients with inflammatory diseases has not led to the desired anti-atherogenic outcome. In this review, the functions of individual protein components of HDL, rendering them either anti-inflammatory or pro-inflammatory are described in detail. Alterations of HDL proteome (such as replacing atheroprotective proteins by pro-inflammatory proteins, or posttranslational modifications) in patients with chronic inflammatory diseases and their impact on cardiovascular health are discussed. Finally, molecular, and clinical aspects of HDL-targeted therapies, including those used in therapeutical practice, drugs in clinical trials, and experimental drugs are comprehensively summarised.

Comparative Analysis of Volatile Constituents in Root Tuber and Rhizome of Curcuma longa L. Using Fingerprints and Chemometrics Approaches on Gas Chromatography-Mass Spectrometry

The root tuber and rhizome of Curcuma longa L., abbreviated, respectively, as RCL and RHCL, are used as different medicines in China. In this work, volatile oils were extracted from RCL and RHCL. Then, gas chromatography-mass spectrometry (GC-MS) was used for RCL and RHCL volatile oils analysis, and 45 compounds were identified. The dominant constituents both in volatile oils of RCL and RHCL were turmerone, (-)-zingiberene, and β-turmerone, which covered more than 60% of the total area. The chromatographic fingerprint similarities between RCL and RHCL were not less than 0.943, indicating that their main chemical compositions were similar. However, there were also some compounds that were varied in RCL and RHCL. Based on the peak area ratio of 45 compounds, the RCL and RHCL samples were separated into principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). Then, 20 compounds with a variable importance for the projection (VIP) value of more than 1 were the high potential contributors for RCL and RHCL differences. Furthermore, ferric ion-reducing antioxidant power (FRAP) assay results demonstrated that the volatile oils of RCL and RHCL had antioxidant activities. This study provided the material basis for the research of volatile components in RCL and RHCL and contributed to their further pharmacological research and quality control.

Curcumin and Weight Loss: Does It Work?

Obesity is a global health problem needing urgent research. Synthetic anti-obesity drugs show side effects and variable effectiveness. Thus, there is a tendency to use natural compounds for the management of obesity. There is a considerable body of knowledge, supported by rigorous experimental data, that natural polyphenols, including curcumin, can be an effective and safer alternative for managing obesity. Curcumin is a is an important compound present in Curcuma longa L. rhizome. It is a lipophilic molecule that rapidly permeates cell membrane. Curcumin has been used as a pharmacological traditional medicinal agent in Ayurvedic medicine for ∼6000 years. This plant metabolite doubtless effectiveness has been reported through increasingly detailed in vitro, in vivo and clinical trials. Regarding its biological effects, multiple health-promoting, disease-preventing and even treatment attributes have been remarkably highlighted. This review documents the status of research on anti-obesity mechanisms and evaluates the effectiveness of curcumin for management of obesity. It summarizes different mechanisms of anti-obesity action, associated with the enzymes, energy expenditure, adipocyte differentiation, lipid metabolism, gut microbiota and anti-inflammatory potential of curcumin. However, there is still a need for systematic and targeted clinical studies before curcumin can be used as the mainstream therapy for managing obesity.

Curcuma longa enhances IFN-γ secretion by natural killer cells through cytokines secreted from macrophages

Interferon-γ (IFN-γ) regulates the human immune system. To study the interaction between macrophages and natural killer (NK) cells, we established a THP-1 macrophage-conditioned media. Among the 58 natural plant extracts tested, Curcuma longa exerted the strongest IFN-γ-enhancing effect in NK-92 cells through THP-1 macrophages. C. longa extract (CLE) enhanced IFN-γ secretion 2.3- and 4.2-fold at 50 and 100 µg/ml, respectively. Therefore, we evaluated its IFN-γ-enhancing effect in vitro. Although NK-92 cells did not produce IFN-γ following treatment with C. longa, enhanced IFN-γ secretion was observed after treatment with THP-1 macrophage-conditioned media. We hypothesized that the cytokines secreted by the CLE-treated THP-1 macrophages are responsible for stimulating NK-92 cells. Cytokine array results show upregulation of cytokines, including MIP-1α, CXCL-1, IL-1β, PAI-1, and TNF-α, in CLE-treated THP-1 macrophages. To determine the cytokines responsible for augmenting IFN-γ secretion, NK-92 cells were stimulated with MIP-1α, CXCL-1, IL-1β, or PAI-1. Enzyme-linked immunosorbent assay results show that all cytokines induced IFN-γ production, although the dose response was somewhat varied. High-performance liquid chromatography analysis of CLE revealed the concentrations of three active curcuminoids, curcumin, demethoxycurcumin, and bisdemethoxycurcumin, as 6.70%, 1.00%, and 0.95%, respectively. Their mixture (with concentrations comparable to their occurrence in CLE) exerted an effect similar to that of the whole CLE. Our findings reveal that CLE indirectly stimulated NK-92 cells to secrete IFN-γ, which is mediated by cytokines produced from THP-1 macrophages. Further, we identified three curcuminoids partly responsible for this IFN-γ-enhancing effect. Therefore, C. longa can be used as a functional food ingredient owing to its immune-boosting ability. PRACTICAL APPLICATION: This study demonstrates that CLE stimulates THP-1 macrophages to secrete cytokines, which can in turn stimulate IFN-γ production by NK-92 cells. A mixture of three curcuminoids present in the extract exerted effects similar to whole CLE, demonstrating that the curcuminoids are partly responsible for the IFN-γ-enhancing effect of C. longa. Since IFN-γ is a key regulator of human immune system, these results suggest the potential use of C. longa as an immune-boosting functional food ingredient.

Curcumin as a Natural Remedy for Atherosclerosis: A Pharmacological Review

Curcumin, a natural polyphenolic compound present in Curcuma longa L. rhizomes, shows potent antioxidant, anti-inflammatory, anti-cancer, and anti-atherosclerotic properties. Atherosclerosis is a comprehensive term for a series of degenerative and hyperplasic lesions such as thickening or sclerosis in large- and medium-sized arteries, causing decreased vascular-wall elasticity and lumen diameter. Atherosclerotic cerebro-cardiovascular disease has become a major concern for human health in recent years due to its clinical sequalae of strokes and heart attacks. Curcumin concoction treatment modulates several important signaling pathways related to cellular migration, proliferation, cholesterol homeostasis, inflammation, and gene transcription, among other relevant actions. Here, we provide an overview of curcumin in atherosclerosis prevention and disclose the underlying mechanisms of action of its anti-atherosclerotic effects.

The Effects of Nano-Curcumin Supplementation on Risk Factors for Cardiovascular Disease: A GRADE-Assessed Systematic Review and Meta-Analysis of Clinical Trials

BACKGROUND

Previous studies have indicated that curcumin supplementation may be beneficial for cardiometabolic health; however, current evidence regarding the effects of its nanorange formulations, popularly known as "nano-curcumin", remains unclear. This systematic review and meta-analysis aimed to determine the impact of nano-curcumin supplementation on risk factors for cardiovascular disease.

METHODS

PubMed, Scopus, Embase, and ISI web of science were systematically searched up to May 2021 using relevant keywords. All randomized controlled trials (RCTs) investigating the effects of nano-curcumin supplementation on cardiovascular disease risk factors were included. Meta-analysis was performed using random-effects models, and subgroup analysis was performed to explore variations by dose and baseline risk profiles.

RESULTS

According to the results of this study, nano-curcumin supplementation was associated with improvements in the glycemic profile by decreasing fasting blood glucose (FBG) (WMD: -18.14 mg/dL; 95% CI: -29.31 to -6.97; p = 0.001), insulin (WMD: -1.21 mg/dL; 95% CI: -1.43 to -1.00; p < 0.001), and HOMA-IR (WMD: -0.28 mg/dL; 95% CI: -0.33 to -0.23; p < 0.001). Interestingly, nano-curcumin supplementation resulted in increases in high-density lipoprotein (HDL) (WMD: 5.77 mg/dL; 95% CI: 2.90 to 8.64; p < 0.001). In terms of other lipid profile markers (triglyceride (TG), total cholesterol (TC), and low-density lipoprotein (LDL)), subgroup analyses showed that nano-curcumin supplementation had more favorable effects on lipid profiles in individuals with dyslipidemia at baseline. Nano-curcumin supplementation also showed favorable anti-inflammatory effects by decreasing C-reactive protein (CRP) (WMD: -1.29 mg/L; 95% CI: -2.15 to -0.44; p = 0.003) and interleukin-6 (IL-6) (WMD: -2.78 mg/dL; 95% CI: -3.76 to -1.79; p< 0.001). Moreover, our results showed the hypotensive effect of nano-curcumin, evidenced by a decrease in systolic blood pressure (SBP).

CONCLUSIONS

In conclusion, our meta-analysis suggests that nano-curcumin supplementation may decline cardiovascular disease risk by improving glycemic and lipid profiles, inflammation, and SBP. Future large-scale investigations with longer durations are needed to expand on our findings.

The Anti-Obesity Effect of Traditional Chinese Medicine on Lipid Metabolism

With the improvement of living conditions and the popularity of unhealthy eating and living habits, obesity is becoming a global epidemic. Obesity is now recognized as a disease that not only increases the risk of metabolic diseases such as type 2 diabetes (T2D), non-alcoholic fatty liver disease (NAFLD), cardiovascular disease (CVD), and cancer but also negatively affects longevity and the quality of life. The traditional Chinese medicines (TCMs) are highly enriched in bioactive compounds and have been used for the treatment of obesity and obesity-related metabolic diseases over a long period of time. In this review, we selected the most commonly used anti-obesity or anti-hyperlipidemia TCMs and, where known, their major bioactive compounds. We then summarized their multi-target molecular mechanisms, specifically focusing on lipid metabolism, including the modulation of lipid absorption, reduction of lipid synthesis, and increase of lipid decomposition and lipid transportation, as well as the regulation of appetite. This review produces a current and comprehensive understanding of integrative and systematic mechanisms for the use of TCMs for anti-obesity. We also advocate taking advantage of TCMs as another therapy for interventions on obesity-related diseases, as well as stressing the fact that more is needed to be done, scientifically, to determine the active compounds and modes of action of the TCMs.

Potential Therapeutic Effects of Curcumin on Glycemic and Lipid Profile in Uncomplicated Type 2 Diabetes-A Meta-Analysis of Randomized Controlled Trial

Diabetes mellitus is an important issue for public health, and it is growing in the world. In recent years, there has been a growing research interest on efficacy evidence of the curcumin use in the regulation of glycemia and lipidaemia. The molecular structure of curcumins allows to intercept reactive oxygen species (ROI) that are particularly harmful in chronic inflammation and tumorigenesis models. The aim of our study performed a systematic review and meta-analysis to evaluate the effect of curcumin on glycemic and lipid profile in subjects with uncomplicated type 2 diabetes. The papers included in the meta-analysis were sought in the MEDLINE, EMBASE, Scopus, Clinicaltrials.gov, Web of Science, and Cochrane Library databases as of October 2020. The sizes were pooled across studies in order to obtain an overall effect size. A random effects model was used to account for different sources of variation among studies. Cohen’s d, with 95% confidence interval (CI) was used as a measure of the effect size. Heterogeneity was assessed while using Q statistics. The ANOVA-Q test was used to value the differences among groups. Publication bias was analyzed and represented by a funnel plot. Curcumin treatment does not show a statistically significant reduction between treated and untreated patients. On the other hand, glycosylated hemoglobin, homeostasis model assessment (HOMA), and low-density lipoprotein (LDL) showed a statistically significant reduction in subjects that were treated with curcumin, respectively (p = 0.008, p < 0.001, p = 0.021). When considering HBA1c, the meta-regressions only showed statistical significance for gender (p = 0.034). Our meta-analysis seems to confirm the benefits on glucose metabolism, with results that appear to be more solid than those of lipid metabolism. However, further studies are needed in order to test the efficacy and safety of curcumin in uncomplicated type 2 diabetes.

Intravenous Curcumin Mitigates Atherosclerosis Progression in Cholesterol-Fed Rabbits

Orally administered curcumin has been found to have a moderate therapeutic effect on dyslipidemia and atherosclerosis. The present study was conducted to determine lipid-modulating and antiatherosclerosis effects of injectable curcumin in the rabbit model of atherosclerosis induced by a high cholesterol diet (HCD). New Zealand white male rabbits were fed on a normal chow enriched with 0.5% (w/w) cholesterol for 8 weeks. Atherosclerotic rabbits were randomly divided into three groups, including a control group receiving intravenous (IV) injection of the saline buffer, two treatment groups receiving IV administration of the injectable curcumin at low (1 mg/kg/week) and high (10 mg/kg/week) over 4 weeks. Plasma lipid parameters, including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), and total cholesterol (TC) were measured. Aortic arch atherosclerotic lesions were assessed using hematoxylin and eosin (H&E) staining. The low dose of curcumin significantly reduced plasma levels of TC, LDL-C, and TG by -14.19 ± 5.19%, -6.22 ± 1.77%, and - 29.84 ± 10.14%, respectively, and increased HDL-C by 14.05 ± 6.39% (p < 0.05). High dose of curcumin exerted greater lipid-modifying effects, in which plasma levels of TC, LDL-C, and TG were significantly (p < 0.05) decreased by -56.59 ± 10.22%, -44.36 ± 3.24%, and - 25.92 ± 5.57%, respectively, and HDL-C was significantly increased by 36.24 ± 12.5%. H&E staining showed that the lesion severity was lowered significantly in the high dose (p = 0.03) but not significantly (p > 0.05) in the low-dose curcumin groups, compared to control rabbits. The median (interquartile range) of plaque grades in the high dose and low dose, and control groups was found to be 2 [2-3], 3 [2-3], and 4 [3-4], respectively. The injectable curcumin could significantly improve dyslipidemia and alleviate atherosclerotic lesion in HCD-induced atherosclerotic rabbits.

Obstacles against the Marketing of Curcumin as a Drug

Among the extensive public and scientific interest in the use of phytochemicals to prevent or treat human diseases in recent years, natural compounds have been highly investigated to elucidate their therapeutic effect on chronic human diseases including cancer, cardiovascular disease, and neurodegenerative disease. Curcumin, an active principle of the perennial herb Curcuma longa, has attracted an increasing research interest over the last half-century due to its diversity of molecular targets, including transcription factors, enzymes, protein kinases, growth factors, inflammatory cytokines, receptors, and it's interesting pharmacological activities. Despite that, the clinical effectiveness of the native curcumin is weak, owing to its low bioavailability and rapid metabolism. Preclinical data obtained from animal models and phase I clinical studies done in human volunteers confirmed a small amount of intestinal absorption, hepatic first pass effect, and some degree of intestinal metabolism, might explain its poor systemic availability when it is given via the oral route. During the last decade, researchers have attempted with new pharmaceutical methods such as nanoparticles, liposomes, micelles, solid dispersions, emulsions, and microspheres to improve the bioavailability of curcumin. As a result, a significant number of bioavailable curcumin-based formulations were introduced with a varying range of enhanced bioavailability. This manuscript critically reviews the available scientific evidence on the basic and clinical effects and molecular targets of curcumin. We also discuss its pharmacokinetic and problems for marketing curcumin as a drug.

Anti-Obesity Effects of Polyphenol Intake: Current Status and Future Possibilities

The prevalence of obesity has steadily increased worldwide over the past three decades. The conventional approaches to prevent or treat this syndrome and its associated complications include a balanced diet, an increase energy expenditure, and lifestyle modification. Multiple pharmacological and non-pharmacological interventions have been developed with the aim of improving obesity complications. Recently, the use of functional foods and their bioactive components is considered a new approach in the prevention and management of this disease. Due to their biological properties, polyphenols may be considered as nutraceuticals and food supplement recommended for different syndromes. Polyphenols are a class of naturally-occurring phytochemicals, some of which have been shown to modulate physiological and molecular pathways involved in energy metabolism. Polyphenols could act in the stimulation of β-oxidation, adipocyte differentiation inhibition, counteract oxidative stress, etc. In this narrative review, we considered the association between polyphenols (resveratrol, quercetin, curcumin, and some polyphenolic extracts) and obesity, focusing on human trials. The health effects of polyphenols depend on the amount consumed and their bioavailability. Some results are contrasting, probably due to the various study designs and lengths, variation among subjects (age, gender, ethnicity), and chemical forms of the dietary polyphenols used. But, in conclusion, the data so far obtained encourage the setting of new trials, necessary to validate benefic role of polyphenols in obese individuals.

The Role of Histone Acetylation and the Microbiome in Phytochemical Efficacy for Cardiovascular Diseases

Cardiovascular diseases (CVD) are the main cause of death worldwide and create a substantial financial burden. Emerging studies have begun to focus on epigenetic targets and re-establishing healthy gut microbes as therapeutic options for the treatment and prevention of CVD. Phytochemicals, commonly found in fruits and vegetables, have been shown to exert a protective effect against CVD, though their mechanisms of action remain incompletely understood. Of interest, phytochemicals such as curcumin, resveratrol and epigallocatechin gallate (EGCG) have been shown to regulate both histone acetylation and microbiome re-composition. The purpose of this review is to highlight the microbiome-epigenome axis as a therapeutic target for food bioactives in the prevention and/or treatment of CVD. Specifically, we will discuss studies that highlight how the three phytochemicals above alter histone acetylation leading to global changes in gene expression and CVD protection. Then, we will expand upon these phytochemicals to discuss the impact of phytochemical-microbiome-histone acetylation interaction in CVD.

Therapeutic Applications of Curcumin Nanomedicine Formulations in Cardiovascular Diseases

Cardiovascular diseases (CVD) compromises a group of heart and blood vessels disorders with high impact on human health and wellbeing. Curcumin (CUR) have demonstrated beneficial effects on these group of diseases that represent a global burden with a prevalence that continues increasing progressively. Pre- and clinical studies have demonstrated the CUR effects in CVD through its anti-hypercholesterolemic and anti-atherosclerotic effects and its protective properties against cardiac ischemia and reperfusion. However, the CUR therapeutic limitation is its bioavailability. New CUR nanomedicine formulations are developed to solve this problem. The present article aims to discuss different studies and approaches looking into the promising role of nanotechnology-based drug delivery systems to deliver CUR and its derivatives in CVD treatment, with an emphasis on their formulation properties, experimental evidence, bioactivity, as well as challenges and opportunities in developing these systems.

Are anti-inflammatory agents and nutraceuticals - novel inhibitors of PCSK9?

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a protease which increases the lysosomal degradation of low density lipoprotein receptor (LDLR) resulting in elevated serum LDL-cholesterol levels. Elevated LDL-cholesterol is the main risk factor for cardiovascular disease (CVD). Antibodies to PCSK9 decrease LDL-cholesterol. Recent studies have suggested a direct relationship between PCSK9 and inflammation and the potential inhibitory effects of anti-inflammatory agents against this enzyme. Nutraceuticals are natural compounds, which have numerous anti-inflammatory and lipid-lowering effects. In this review we focus on anti-inflammatory substances and nutraceuticals, which are beneficial in treatment of dyslipidemia. We also reviewed the recent findings concerning the role of PCSK9 as the main target for molecular mechanisms of these substances.

Mechanics insights of curcumin in myocardial ischemia: Where are we standing?

Cardiovascular disorders are known as one of the main health problems which are associated with mortality worldwide. Myocardial ischemia (MI) is improper blood supply to myocardium which leads from serious complications to life-threatening problems like AMI, atherosclerosis, hypertension, cardiac-hypertrophy as well as diabetic associated complications as diabetic atherosclerosis/cardiomyopathy/hypertension. Despite several efforts, the current therapeutic platforms are not related with significant results. Hence, it seems, developing novel therapies are required. In this regard, increasing evidences indicated, curcumin (CRC) acts as cardioprotective agent. Given that CRC and its analogs exert their cardioprotective effects via affecting on a variety of cardiovascular diseases-related mechanisms (i.e., Inflammation, and oxidative stress). Herein, for first time, we have highlighted the protective impacts of CRC against MI. This review might be a steppingstone for further investigation into the clinical implications of the CRC against MI. Furthermore, it pulls in light of a legitimate concern for scientific community, seeking novel techniques and characteristic dynamic biopharmaceuticals for use against myocardial ischemia.

The therapeutic potential of curcumin: A review of clinical trials

Curcuma longa L., its derived extracts and even its major compound curcumin has a long history of use and doubtless effectiveness, reported through increasingly detailed in vitro, ex vivo, in vivo and even clinical trials. Regarding its biological effects, multiple health-promoting, disease-preventing and even treatment attributes has been remarkably highlighted. Clinical trials, although have increased in a progressive manner, significant disproportionalities have been stated in terms of biological effects assessment. In this sense, the present report aims to provide an extensive overview to curcumin therapeutic effects in human subjects. For that, clinical trials assessing the curcumin effect on inflammation, skin, eye, central nervous system, respiratory, cardiovascular, gastrointestinal, urogenital and metabolic disorders are here presented and discussed. A special emphasis was also given to curcumin activity on intoxications and multiple malignant diseases.

Relationship between Mediterranean Dietary Polyphenol Intake and Obesity

Obesity is a multifactorial and complex disease defined by excess of adipose mass and constitutes a serious health problem. Adipose tissue acts as an endocrine organ secreting a wide range of inflammatory adipocytokines, which leads to systemic inflammation, insulin resistance, and metabolic disorders. The traditional Mediterranean diet is characterized by a high phenolic-rich foods intake, including extra-virgin olive oil, nuts, red wine, vegetables, fruits, legumes, and whole-grain cereals. Evidence for polyphenols’ effect on obesity and weight control in humans is inconsistent and the health effects of polyphenols depend on the amount consumed and their bioavailability. The mechanisms involved in weight loss in which polyphenols may have a role are: activating β-oxidation; a prebiotic effect for gut microbiota; inducing satiety; stimulating energy expenditure by inducing thermogenesis in brown adipose tissue; modulating adipose tissue inhibiting adipocyte differentiation; promoting adipocyte apoptosis and increasing lipolysis. Even though the intake of some specific polyphenols has been associated with body weight changes, there is still no evidence for the effects of total polyphenols or some polyphenol subclasses in humans on adiposity.

Supplementation with curcumin inhibits intestinal cholesterol absorption and prevents atherosclerosis in high-fat diet-fed apolipoprotein E knockout mice

Atherosclerosis is a major cause of cardiovascular disease caused by high cholesterol. Reduced intestinal cholesterol absorption has been shown to exert strong cholesterol-lowering and antiatherogenic effects. Previously, we reported that curcumin reduced cholesterol absorption in high-fat diet-fed hamster by downregulating the intestinal expression of Niemann-Pick C1-like 1. Here, we tested the hypothesis that supplementation with curcumin can also reduce intestinal cholesterol absorption in high-fat diet-fed apolipoprotein E knockout (ApoE^-/-) mice and prevent atherosclerosis development. ApoE^-/- mice were fed a high-fat diet supplemented with or without curcumin (0.1% w/w) for 16 weeks. Aortic sinus sections revealed that curcumin supplementation reduced the extent of atherosclerotic lesions by 45%. Curcumin treatment also reduced cholesterol accumulation in the aortas by 56% and lowered plasma total cholesterol and low-density lipoprotein cholesterol levels. Moreover, the antiatherogenic and cholesterol-lowering effects of curcumin coincided with a significant decrease in intestinal cholesterol absorption. It was reduced by nearly 51%, and the decreased cholesterol absorption was modulated by inhibiting the intestinal expression of Niemann-Pick C1-like 1, predominantly in the duodenal and jejunal segments of the small intestine. These findings support the hypothesis that curcumin supplementation reduces intestinal cholesterol absorption and prevents atherosclerosis in high-fat diet-fed ApoE^-/- mice. Curcumin affords a potent antiatherogenic action by inhibiting intestinal cholesterol absorption in the mouse.

Efficacy and safety of turmeric and curcumin in lowering blood lipid levels in patients with cardiovascular risk factors: a meta-analysis of randomized controlled trials

Background

Dyslipidemia is an important and common cardiovascular risk factor in the general population. The lipid-lowering effects of turmeric and curcumin are unconfirmed. We performed a meta-analysis to assess the efficacy and safety of turmeric and curcumin in lowering blood lipids in patients at risk of cardiovascular disease (CVD).

Methods

A comprehensive literature search was conducted on PubMed, Embase, Ovid, Medline and Cochrane Library databases to identify randomized controlled trials (published as of November 2016) that assessed the effect of turmeric and curcumin on blood lipid levels including total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG). Pooled standardized mean difference (SMD) with 95% confidence interval (CI) was used to assess the effect.

Results

The analysis included 7 eligible studies (649 patients). Turmeric and curcumin significantly reduced serum LDL-C (SMD = −0.340, 95% confidence interval [CI]: −0.530 to −0.150, P < 0.0001) and TG (SMD = −0.214, 95% CI: −0.369 to −0.059, P = 0.007) levels as compared to those in the control group. These may be effective in lowering serum TC levels in patients with metabolic syndrome (MetS, SMD = −0.934, 95% CI: −1.289 to −0.579, P < 0.0001), and turmeric extract could possibly have a greater effect on reducing serum TC levels (SMD = −0.584, 95% CI: −0.980 to −0.188, P = 0.004); however, the efficacy is yet to be confirmed. Serum HDL-C levels were not obviously improved. Turmeric and curcumin appeared safe, and no serious adverse events were reported in any of the included studies.

Conclusions

Turmeric and curcumin may protect patients at risk of CVD through improving serum lipid levels. Curcumin may be used as a well-tolerated dietary adjunct to conventional drugs. Further research is required to resolve uncertainties related to dosage form, dose and medication frequency of curcumin.

Electronic supplementary material

The online version of this article (10.1186/s12937-017-0293-y) contains supplementary material, which is available to authorized users.

Regulation of PCSK9 by nutraceuticals

PCSK9 (proprotein convertase subtilisin kexin type 9) is a liver secretory enzyme that regulates plasma low-density lipoprotein (LDL) cholesterol (LDL-C) levels through modulation of LDL receptor (LDLR) density on the surface of hepatocytes. Inhibition of PCSK9 using monoclonal antibodies can efficiently lower plasma LDL-C, non-high-density lipoprotein cholesterol and lipoprotein (a). PCSK9 inhibition is also an effective adjunct to statin therapy; however, the cost-effectiveness of currently available PCSK9 inhibitors is under question. Nutraceuticals offer a safe and cost-effective option for PCSK9 inhibition. Several nutraceuticals have been reported to modulate PCSK9 levels and exert LDL-lowering activity. Mechanistically, those nutraceuticals that inhibit PCSK9 through a SREBP (sterol-responsive element binding protein)-independent pathway can be more effective in lowering plasma LDL-C levels compared with those inhibiting PCSK9 through the SREBP pathway. The present review aims to collect available data on the nutraceuticals with PCSK9-inhibitory effect and the underlying mechanisms.

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.

A Systematic Review of the Efficacy of Bioactive Compounds in Cardiovascular Disease: Phenolic Compounds

The prevalence of cardiovascular diseases (CVD) is rising and is the prime cause of death in all developed countries. Bioactive compounds (BAC) can have a role in CVD prevention and treatment. The aim of this work was to examine the scientific evidence supporting phenolic BAC efficacy in CVD prevention and treatment by a systematic review. Databases utilized were Medline, LILACS and EMBASE, and all randomized controlled trials (RCTs) with prospective, parallel or crossover designs in humans in which the effects of BAC were compared with that of placebo/control were included. Vascular homeostasis, blood pressure, endothelial function, oxidative stress and inflammatory biomarkers were considered as primary outcomes. Cohort, ecological or case-control studies were not included. We selected 72 articles and verified their quality based on the Scottish Intercollegiate Guidelines Network, establishing diverse quality levels of scientific evidence according to two features: the design and bias risk of a study. Moreover, a grade of recommendation was included, depending on evidence strength of antecedents. Evidence shows that certain polyphenols, such as flavonols can be helpful in decreasing CVD risk factors. However, further rigorous evidence is necessary to support the BAC effect on CVD prevention and treatment.

Effects of curcumin on the gene expression profile of L-02 cells

Curcumin has been utilized in the treatment and prevention of disease, including cancer and cardiovascular disease, but the molecular mechanism behind such numerous effects remains unclear. To explore the molecular mechanism and action sites of curcumin at the cellular level, human hepatic L-02 cells were used to assess these effects. Microarray technology was employed to detect the gene expression of L-02 cells treated with curcumin. According to the microarray results and the data from the National Center for Biotechnology Information, the present study classified and concluded that these curcumin-sensitive genes were associated with diseases and their signaling pathway. The study supports the evidence for treating cancer and cardiovascular disease, and found certain potential marker genes for conducting systematic research into the effects of curcumin. A total of 80 genes were identified as significantly differentially expressed between samples treated with and without curcumin. Curcumin is capable of developing physiological reactions and functions by regulating the gene expression and affecting its signal transduction pathway. Tumor protein p63, MYC-associated factor X and certain other genes associated with tumors act on a potential therapeutic target, while apolipoprotein B receptor and oxysterol-binding protein-like 7, and their signaling pathways may be involved in the cardioprotective effects of curcumin.

Novel insights of dietary polyphenols and obesity

The prevalence of obesity has steadily increased over the past three decades both in the United States and worldwide. Recent studies have shown the role of dietary polyphenols in the prevention of obesity and obesity-related chronic diseases. Here, we evaluated the impact of commonly consumed polyphenols, including green tea catechins, especially epigallocatechin gallates, resveratrol and curcumin, on obesity and obesity-related inflammation. Cellular studies demonstrated that these dietary polyphenols reduce viability of adipocytes and proliferation of preadipocytes, suppress adipocyte differentiation and triglyceride accumulation, stimulate lipolysis and fatty acid β-oxidation, and reduce inflammation. Concomitantly, the polyphenols modulate signaling pathways including the adenosine-monophosphate-activated protein kinase, peroxisome proliferator activated receptor γ, CCAAT/enhancer binding protein α, peroxisome proliferator activator receptor gamma activator 1-alpha, sirtuin 1, sterol regulatory element binding protein-1c, uncoupling proteins 1 and 2, and nuclear factor-κB that regulate adipogenesis, antioxidant and anti-inflammatory responses. Animal studies strongly suggest that commonly consumed polyphenols described in this review have a pronounced effect on obesity as shown by lower body weight, fat mass and triglycerides through enhancing energy expenditure and fat utilization, and modulating glucose hemostasis. Limited human studies have been conducted in this area and are inconsistent about the antiobesity impact of dietary polyphenols probably due to the various study designs and lengths, variation among subjects (age, gender, ethnicity), chemical forms of the dietary polyphenols used and confounding factors such as other weight-reducing agents. Future randomized controlled trials are warranted to reconcile the discrepancies between preclinical efficacies and inconclusive clinic outcomes of these polyphenols.

Reduction of atherogenic risk in patients with type 2 diabetes by curcuminoid extract: a randomized controlled trial

Curcumin is a phytocompound found in the root of turmeric, a common herbal ingredient in many Asian cuisines. The compound contains anti-inflammatory activity, which is mediated through an up-regulation of adiponectin and reduction of leptin. Consumption of curcumin was shown to prevent some deteriorative conditions caused by inflammation, such as ulcerative colitis, rheumatoid arthritis and esophagitis, and so on. Inflammation-associated cardiovascular conditions such as atherosclerosis are common in diabetes patients. The anti-inflammation effect of curcumin might be beneficial to prevent such condition in these patients. We aim to evaluate an antiatherosclerosis effect of curcumin in diabetes patients. Effects of curcumin on risk factors for atherosclerosis were investigated in a 6-month randomized, double-blinded and placebo-controlled clinical trial that included subjects diagnosed with type 2 diabetes. An atherosclerosis parameter, the pulse wave velocity, and other metabolic parameters in patients treated with placebo and curcumin were compared. Our results showed that curcumin intervention significantly reduced pulse wave velocity, increased level of serum adiponectin and decreased level of leptin. These results are associated with reduced levels of homeostasis model assessment-insulin resistance, triglyceride, uric acid, visceral fat and total body fat. In summary, a 6-month curcumin intervention in type 2 diabetic population lowered the atherogenic risks. In addition, the extract helped to improve relevant metabolic profiles in this high-risk population.

Targeted delivery of curcumin for treating type 2 diabetes

Type 2 diabetes is a chronic condition in which cells have reduced insulin signalling, leading to hyperglycemia and long-term complications, including heart, kidney and liver disease. Macrophages activated by dying or stressed cells, induce the transcription factor nuclear factor kappa-B leading to the production of pro-inflammatory cytokines including TNF and IL-6. These inflammatory macrophages in liver and adipose tissue promote insulin resistance, and medications which reduce inflammation and enhance insulin signalling improve glucose control. Curcumin is an anti-oxidant and nuclear factor kappa-B inhibitor derived from turmeric. A number of studies have shown that dietary curcumin reduces inflammation and delays or prevents obesity-induced insulin resistance and associated complications, including atherosclerosis and immune mediate liver disease. Unfortunately dietary curcumin is poorly absorbed by the digestive system and undergoes glucuronidation and excretion rather than being released into the serum and systemically distributed. This confounds understanding of how dietary curcumin exerts its beneficial effects in type 2 diabetes and associated diseases. New improved methods of delivering curcumin are being developed including nanoparticles and lipid/liposome formulations that increase absorption and bioavailability of curcumin. Development and refinement of these technologies will enable cell-directed targeting of curcumin and improved therapeutic outcome.

Insulin-like growth-factor-1-induced PKB signaling and Egr-1 expression is inhibited by curcumin in A-10 vascular smooth muscle cells

Insulin-like growth factor 1 (IGF-1) is a mitogenic factor that stimulates the signaling pathways responsible for inducing hypertrophic and proliferative responses in vascular smooth muscle cells (VSMC). We have previously demonstrated that IGF-1 receptor (IGF-1R) plays a key role in transducing the hypertrophic and proliferative responses of angiotensin II (Ang-II) and endothelin-1 (ET-1). Curcumin, a polyphenolic compound derived from the spice turmeric is known to possess antiproliferative properties and exerts vasculoprotective effects. However, the ability of curcumin to modulate IGF-1-induced signaling responses in VSMC remains to be investigated. In this study, we determined the effect of curcumin on IGF-1-induced phosphorylation of protein kinase B (PKB), glycogen synthase kinase-3β (GSK-3β), and IGF-1R in VSMC. Curcumin inhibited IGF-1-induced phosphorylation of PKB and GSK-3β as well as the IGF-1R β subunit in a dose-dependent fashion. In addition, IGF-1-induced expression of early growth response protein 1 (Egr-1) which plays a pathogenic role in vascular dysfunctions, was also attenuated by curcumin. In conclusion, these results indicate that curcumin is a potent inhibitor of key components of the IGF-1-induced mitogenic and proliferative signaling system in VSMC, and suggest that curcumin-induced attenuation of these signaling components may constitute a potential mechanism for its vasculoprotective effects.

Targeting inflammation-induced obesity and metabolic diseases by curcumin and other nutraceuticals

Extensive research within the past two decades has revealed that obesity, a major risk factor for type 2 diabetes, atherosclerosis, cancer, and other chronic diseases, is a proinflammatory disease. Several spices have been shown to exhibit activity against obesity through antioxidant and anti-inflammatory mechanisms. Among them, curcumin, a yellow pigment derived from the spice turmeric (an essential component of curry powder), has been investigated most extensively as a treatment for obesity and obesity-related metabolic diseases. Curcumin directly interacts with adipocytes, pancreatic cells, hepatic stellate cells, macrophages, and muscle cells. There, it suppresses the proinflammatory transcription factors nuclear factor-kappa B, signal transducer and activators of transcription-3, and Wnt/beta-catenin, and it activates peroxisome proliferator-activated receptor-gamma and Nrf2 cell-signaling pathways, thus leading to the downregulation of adipokines, including tumor necrosis factor, interleukin-6, resistin, leptin, and monocyte chemotactic protein-1, and the upregulation of adiponectin and other gene products. These curcumin-induced alterations reverse insulin resistance, hyperglycemia, hyperlipidemia, and other symptoms linked to obesity. Other structurally homologous nutraceuticals, derived from red chili, cinnamon, cloves, black pepper, and ginger, also exhibit effects against obesity and insulin resistance.

Application of Scion image software to the simultaneous determination of curcuminoids in turmeric (Curcuma longa)

INTRODUCTION

Curcumin, desmethoxycurcumin and bisdesmethoxycurcumin are bioactive constituents of turmeric (Curcuma longa). Owing to their different potency, quality control of turmeric based on the content of each curcuminoid is more reliable than that based on total curcuminoids. However, to perform such an assay, high-cost instrument is needed.

OBJECTIVE

To develop a simple and low-cost method for the simultaneous quantification of three curcuminoids in turmeric using TLC and the public-domain software Scion Image.

METHODOLOGY

The image of a TLC chromatogram of turmeric extract was recorded using a digital scanner. The density of the TLC spot of each curcuminoid was analysed by the Scion Image software. The density value was transformed to concentration by comparison with the calibration curve of standard curcuminoids developed on the same TLC plate.

RESULTS

The polynomial regression data for all curcuminoids showed good linear relationship with R(2) > 0.99 in the concentration range of 0.375-6 microg/spot. The limits of detection and quantitation were 43-73 and 143-242 ng/spot, respectively. The method gave adequate precision, accuracy and recovery. The contents of each curcuminoid determined using this method were not significantly different from those determined using the TLC densitometric method.

CONCLUSION

TLC image analysis using Scion Image is shown to be a reliable method for the simultaneous analysis of the content of each curcuminoid in turmeric.