Curcumin and obesity: evidence and mechanisms

Impact of exercise intervention with or without curcumin supplementation on body fat composition, glucose, and lipid metabolism in obese adults: A meta-analysis

This study was carried out to systematically review and evaluate the influence of exercise with and without curcumin on body fat composition, glucose, and lipid metabolism in obese adults. Search for eligible studies through four databases, and then proceed with screening. The inclusion criteria are as follows: (1) obese adults; (2) randomized controlled trial (RCT); (3) classified the exercise intervention with curcumin supplementation as the exercise with curcumin (CU) group and without curcumin supplementation as the exercise without curcumin (EX) group; (4) Conducted pre- and post-training assessments, which include body fat composition, glucose and lipid metabolism parameters. Use the Cochrane bias risk assessment tool to evaluate the quality of the selected study. Select standardized mean difference (SMD) as the appropriate effect scale index, and use Revman 5.4 software to analyze the mean difference of the selected article data with a 95% confidence interval (CI). A total of seven studies fulfilled the inclusion criteria and were selected for the meta-analysis. The included studies involved 72 males and 111 females, where 94 belonged to the EX group and 89 from the CU group. The CU group benefited more from the reduced Fat% (SMD, 2.18 [0.12, 4.24], p < 0.05, I2 = 0%, p for heterogeneity = 0.98) than the EX group. The study demonstrated that the combined exercise intervention with curcumin supplementation significantly reduced Fat% in obese adults compared with exercise without supplementing curcumin.

Does curcumin supplementation affect inflammation, blood count and serum brain-derived neurotropic factor concentration in amateur long-distance runners?

Curcumin is known for its potential health benefits; however, the evidence remains inconclusive regarding its necessity as a supplement for athletes during the preparatory phase of training. This study aimed to assess the effect of 6-week curcumin supplementation at a dose of 2g/day on selected inflammatory markers, blood count, and brain-derived neurotropic factor (BDNF) levels in middle-aged amateur long-distance runners during the preparatory period of a macrocycle. Thirty runners were randomly assigned to either a curcumin-supplemented group (CUR, n = 15) or a placebo group (PLA, n = 15). Venous blood samples were collected at rest, immediately post-exercise, and 1h post-exercise. The participants underwent a graded exercise stress test, with an increasing inclination angle after reaching a speed of 14 km/h, both before and after the 6-week supplementation period. Blood samples were collected at rest, 3 minutes post-stress test, and after 1 hour of recovery. The results showed no significant changes in C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor α (TNF-α), interleukin-1 β (IL-1β), or blood morphology due to curcumin supplementation. However, BDNF levels increased by 21% in the CUR group post-supplementation, while a 5% decrease was observed in the PLA group. These findings do not support a significant effect of curcumin supplementation on inflammatory markers, blood count, or BDNF concentration. Further research is warranted to determine the potential benefits of curcumin supplementation for endurance athletes during the preparatory period for a training cycle.

Assessing Therapeutic Value and Side Effects of Key Botanical Compounds for Optimized Medical Treatments

Due to the significance of variable chemical groups across a wide spectrum of modern medicine, it is imperative to determine what is the most widely used group in medical applications with the fewest side effects. Ten compounds from ten chemical groups that are most commonly known for their medical uses were compared in terms of their therapeutic potential and side effects. The comparison among the selected compounds indicated the superiority of the flavonoids over other groups in the multitude of their utilizations and the lower side effects. Kaempferol and quercetin showed higher medical utilization with lower side effects. Whereas alkaloid compounds showed the lowest levels of medical use and the highest levels of side effects. Based on the comparison conducted, it is concluded to give priority to flavonoid compounds being used in medical applications because they exhibit the highest medical uses with the lowest side effects. Within flavonoids, kaempferol and quercetin are the two compounds that are highly recommended to be used in the widest range of medical applications. Serious caution should be considered before applying alkaloids to any medical service. Understanding the characteristics of these compounds can aid in developing safer and more effective treatments for medicinal plants.

Curcumin Mitigates Muscle Atrophy Potentially by Attenuating Calcium Signaling and Inflammation in a Spinal Nerve Ligation Model

Denervation-induced calcium/calmodulin-dependent protein kinase II (CaMKII) activation and inflammation can result in muscle atrophy. Curcumin and bisdemethoxycurcumin are well known to exhibit an anti-inflammatory effect. In addition, curcumin has been shown to attenuate CaMKII activation in neuronal cells. This study aimed to examine the effect of curcumin or bisdemethoxycurcumin on CaMKII activation, inflammation, and muscle cross-sectional area (CSA) in spinal nerve ligated rats. Sixteen female rats were assigned to sham (CON), spinal nerve ligation (SNL), SNL+ curcumin 100 mg/kg BW (100CUR), and SNL+ bisdemethoxycurcumin 50 mg/kg BW (50CMO) for 4 weeks. Ipsilateral (surgical) soleus and tibialis anterior (TA) muscles was stained for dystrophin to measure CSA. Ipsilateral and contralateral (non-surgical) plantaris muscles were analyzed for protein content for acetylcholine receptor (AChR), CaMKII, CaMKIIThr286, nuclear factor-κB (NF-κB), NF-κBSer536, and interleukin-1β (IL-1β) and normalized to α-tubulin and then CON. A significant (p < 0.050) group effect was observed for TA CSA where CON (11,082.25 ± 1617.68 μm2; p < 0.001) and 100CUR (9931.04 ± 2060.87 μm2; p = 0.018) were larger than SNL (4062.25 ± 151.86 μm2). In the ipsilateral plantaris, the SNL (4.49 ± 0.69) group had greater CaMKII activation compared to CON (1.00 ± 0.25; p = 0.010), 100CUR (1.12 ± 0.45; p = 0.017), and 50CMO (0.78 ± 0.19; p = 0.009). The ipsilateral plantaris (2.11 ± 0.66) had greater IL-1β protein content than the contralateral leg (0.65 ± 0.14; p = 0.041) in the SNL group. In plantaris, the SNL (1.65 ± 0.51) group had greater NF-κB activation compared to CON (1.00 ± 0.29; p = 0.021), 100CUR (0.61 ± 0.10; p = 0.003), 50CMO (0.77 ± 0.25; p = 0.009) groups. The observed reduction in Ca2+ signaling and inflammation in type II plantaris muscle fibers might reflect the changes within the type II TA muscle fibers which may contribute to the mitigation of TA mass loss with curcumin supplementation.

The beneficial impact of curcumin on cardiac lipotoxicity

Lipotoxicity is defined as a prolonged metabolic imbalance of lipids that results in ectopic fat distribution in peripheral organs such as the liver, heart, and kidney. The harmful consequences of excessive lipid accumulation in cardiomyocytes cause cardiac lipotoxicity, which alters the structure and function of the heart. Obesity and diabetes are linked to lipotoxic cardiomyopathy. These anomalies might be caused by a harmful metabolic shift that accumulates toxic lipids and shifts glucose oxidation to less fatty acid oxidation. Research has linked fatty acids, fatty acyl coenzyme A, diacylglycerol, and ceramide to lipotoxic stress in cells. This stress can be brought on by apoptosis, impaired insulin signaling, endoplasmic reticulum stress, protein kinase C activation, p38 Ras-mitogen-activated protein kinase (MAPK) activation, or modification of peroxisome proliferator-activated receptors (PPARs) family members. Curcuma longa is used to extract curcumin, a hydrophobic polyphenol derivative with a variety of pharmacological characteristics. Throughout the years, curcumin has been utilized as an anti-inflammatory, antioxidant, anticancer, hepatoprotective, cardioprotective, anti-diabetic, and anti-obesity drug. Curcumin reduces cardiac lipotoxicity by inhibiting apoptosis and decreasing the expression of apoptosis-related proteins, reducing the expression of inflammatory cytokines, activating the autophagy signaling pathway, and inhibiting the expression of endoplasmic reticulum stress marker proteins.

Herbal Products as Complementary or Alternative Medicine for the Management of Hyperglycemia and Dyslipidemia in Patients with Type 2 Diabetes: Current Evidence Based on Findings of Interventional Studies

Type 2 diabetes (T2D) is known as a major public health problem with a noticeable adverse impact on quality of life and health expenditures worldwide. Despite using routine multiple pharmacological and nonpharmacological interventions, including diet therapy and increasing physical activity, controlling this chronic disease remains a challenging issue, and therapeutic goals are often not achieved. Therefore, recently, other therapeutic procedures, such as using herbal products and functional foods as complementary or alternative medicine (CAM), have received great attention as a new approach to managing T2D complications, according to the literature. We reviewed the existing evidence that supports using various fundamental medicinal herbs, including cinnamon, saffron, ginger, jujube, turmeric, and barberry, as CAM adjunctive therapeutic strategies for T2D patients. The current review addressed different aspects of the potential impact of the abovementioned herbal products in improving glycemic indices and lipid profiles, including the effect size reported in the studies, their effective dose, possible side effects, herbs-drug interactions, and their potential action mechanisms.

Two Prenylated Chalcones, 4-Hydroxyderricin, and Xanthoangelol Prevent Postprandial Hyperglycemia by Promoting GLUT4 Translocation via the LKB1/AMPK Signaling Pathway in Skeletal Muscle Cells

SCOPE

Stimulation of glucose uptake in the skeletal muscle is crucial for the prevention of postprandial hyperglycemia. Insulin and certain polyphenols enhance glucose uptake through the translocation of glucose transporter 4 (GLUT4) in the skeletal muscle. The previous study reports that prenylated chalcones, 4-hydroxyderricin (4-HD), and xanthoangelol (XAG) promote glucose uptake and GLUT4 translocation in L6 myotubes, but their underlying molecular mechanism remains unclear. This study investigates the mechanism in L6 myotubes and confirms antihyperglycemia by 4-HD and XAG.

METHODS AND RESULTS

In L6 myotubes, 4-HD and XAG promote glucose uptake and GLUT4 translocation through the activation of adenosine monophosphate-activated protein kinase (AMPK) and liver kinase B1 (LKB1) signaling pathway without activating phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) and Janus kinases (JAKs)/signal transducers and activators of transcriptions (STATs) pathways. Moreover, Compound C, an AMPK-specific inhibitor, as well as siRNA targeting AMPK and LKB1 completely canceled 4-HD and XAG-increased glucose uptake. Consistently, oral administration of 4-HD and XAG to male ICR mice suppresses acute hyperglycemia in an oral glucose tolerance test.

CONCLUSION

In conclusion, LKB1/AMPK pathway and subsequent GLUT4 translocation in skeletal muscle cells are involved in Ashitaba chalcone-suppressed acute hyperglycemia.

Evaluating the Therapeutic Potential of Curcumin and Synthetic Derivatives: A Computational Approach to Anti-Obesity Treatments

Natural compounds such as curcumin, a polyphenolic compound derived from the rhizome of turmeric, have gathered remarkable scientific interest due to their diverse metabolic benefits including anti-obesity potential. However, curcumin faces challenges stemming from its unfavorable pharmacokinetic profile. To address this issue, synthetic curcumin derivatives aimed at enhancing the biological efficacy of curcumin have previously been developed. In silico modelling techniques have gained significant recognition in screening synthetic compounds as drug candidates. Therefore, the primary objective of this study was to assess the pharmacokinetic and pharmacodynamic characteristics of three synthetic derivatives of curcumin. This evaluation was conducted in comparison to curcumin, with a specific emphasis on examining their impact on adipogenesis, inflammation, and lipid metabolism as potential therapeutic targets of obesity mechanisms. In this study, predictive toxicity screening confirmed the safety of curcumin, with the curcumin derivatives demonstrating a safe profile based on their LD50 values. The synthetic curcumin derivative 1A8 exhibited inactivity across all selected toxicity endpoints. Furthermore, these compounds were deemed viable candidate drugs as they adhered to Lipinski's rules and exhibited favorable metabolic profiles. Molecular docking studies revealed that both curcumin and its synthetic derivatives exhibited favorable binding scores, whilst molecular dynamic simulations showed stable binding with peroxisome proliferator-activated receptor gamma (PPARγ), csyclooxygenase-2 (COX2), and fatty acid synthase (FAS) proteins. The binding free energy calculations indicated that curcumin displayed potential as a strong regulator of PPARγ (-60.2 ± 0.4 kcal/mol) and FAS (-37.9 ± 0.3 kcal/mol), whereas 1A8 demonstrated robust binding affinity with COX2 (-64.9 ± 0.2 kcal/mol). In conclusion, the results from this study suggest that the three synthetic curcumin derivatives have similar molecular interactions to curcumin with selected biological targets. However, in vitro and in vivo experimental studies are recommended to validate these findings.

Natural compounds as obesity pharmacotherapies

Obesity has become a serious global public health problem, affecting over 988 million people worldwide. Nevertheless, current pharmacotherapies have proven inadequate. Natural compounds have garnered significant attention due to their potential antiobesity effects. Over the past three decades, ca. 50 natural compounds have been evaluated for the preventive and/or therapeutic effects on obesity in animals and humans. However, variations in the antiobesity efficacies among these natural compounds have been substantial, owing to differences in experimental designs, including variations in animal models, dosages, treatment durations, and administration methods. The feasibility of employing these natural compounds as pharmacotherapies for obesity remained uncertain. In this review, we systematically summarized the antiobesity efficacy and mechanisms of action of each natural compound in animal models. This comprehensive review furnishes valuable insights for the development of antiobesity medications based on natural compounds.

Overview of Natural Supplements for the Management of Diabetes and Obesity

Bioactive compounds found in various natural sources, such as fruits, vegetables, and herbs, have been studied for their potential benefits in managing obesity and diabetes. These compounds include polyphenols, flavonoids, other antioxidants, fiber, and certain fatty acids. Studies have found that these compounds may improve insulin sensitivity, regulate blood sugar levels, and promote weight loss. However, the effects of these compounds can vary depending on the type and amount consumed, as well as individual factors, such as genetics and lifestyle. Nutraceutical substances have multifaceted therapeutic advantages, and they have been reported to have disease-prevention and health-promoting properties. Several clinically used nutraceuticals have been shown to target the pathogenesis of diabetes mellitus, obesity, and metabolic syndrome and their complications and modulate various clinical outcomes favorably. This review aims to highlight and comment on some of the most prominent natural components used as antidiabetics and in managing obesity.

Diet of Broilers with Essential Oil from Citrus sinensis and Xylopia aromatica Fruits

This study aimed to evaluate the effects of essential oils from the fruits of Citrus sinensis and Xylopia aromatica, included in broiler feed, on blood parameters, the biometrics of digestive organs, bone analyses, and the biochemical profiles of the viscera, as well as the histomorphometry of the small intestine. In this study, 180 one-day-old male chicks of the Cobb 500 strain were fed a corn and soybean meal over three treatments and six replications, and the experimental design was completely randomized. The data were subjected to an analysis of variance and a Tukey test at a 5% significance level. The effect of the experimental diets on performance, blood parameters, biometrics of the digestive organs, bone analysis, and biochemical profiles of the viscera, as well as the histomorphometry of the small intestine, were evaluated. The compounds identified in the essential oil of X. aromatica were sylvestrene, α-pinene, and β-pinene, while in C. sinensis they were limonene and myrcene. The essential oils of C. sinensis and X. aromatica had no significant effect on performance at 14 days. The effects of the presence of the essential oils of C. sinensis and X. aromatica on the response were beneficial: there were reductions in liver lipids, cholesterol, and triglycerides, and in the depths of the crypts in the jejunum of chickens. So, the essential oils from the fruits of C. sinensis and X. aromatica can be used in broiler chickens to improve the lipid profiles of birds without affecting their performance.

The effect of curcumin on anthropometric indices, blood pressure, lipid profiles, fasting blood glucose, liver enzymes, fibrosis, and steatosis in non-alcoholic fatty livers

Background

Non-alcoholic fatty liver disease (NAFLD) is the most common form of liver disease. Curcumin is a natural polyphenol that may be effective against liver steatosis and steatohepatitis. The present study aimed to evaluate the effects of phytosomal curcumin on lipid profile, fasting blood sugar, anthropometric indices, liver enzymes, fibrosis, and steatosis in non-alcoholic fatty liver patients.

Methods

The participants were randomized to the curcumin-phosphatidylserine phytosomal receiving group and the placebo receiving group and were followed up for 12 weeks. Data on anthropometric indices, lipid profile, blood glucose, blood pressure, liver enzymes, hepatic steatosis, and fibrosis were collected at the beginning and the end of the clinical trial.

Results

Supplementation for 12 weeks with phytosomal curcumin significantly reduced fibrosis and steatosis in the phytosomal curcumin receiving group compared with the placebo group (p < 0.05). Phytosomal curcumin also significantly reduced waist circumference and blood pressure compared with the placebo group (p < 0.05). There was no significant difference between the phytosomal curcumin and the placebo groups regarding changes in weight, body mass index, fasting blood glucose, liver enzymes, and lipid profile.

Conclusion

Curcumin, at a dose of 250 mg per day, might be effective in treating patients with NAFLD. Further studies are necessary to confirm these findings and to discover the underlying mechanisms.

Clinical trial registration

https://www.irct.ir/trial/43730, identifier: IRCT20121216011763N39.

An Integrated Approach to Skeletal Muscle Health in Aging

A decline in muscle mass and function represents one of the most problematic changes associated with aging, and has dramatic effects on autonomy and quality of life. Several factors contribute to the inexorable process of sarcopenia, such as mitochondrial and autophagy dysfunction, and the lack of regeneration capacity of satellite cells. The physiologic decline in muscle mass and in motoneuron functionality associated with aging is exacerbated by the sedentary lifestyle that accompanies elderly people. Regular physical activity is beneficial to most people, but the elderly need well-designed and carefully administered training programs that improve muscle mass and, consequently, both functional ability and quality of life. Aging also causes alteration in the gut microbiota composition associated with sarcopenia, and some advances in research have elucidated that interventions via the gut microbiota-muscle axis have the potential to ameliorate the sarcopenic phenotype. Several mechanisms are involved in vitamin D muscle atrophy protection, as demonstrated by the decreased muscular function related to vitamin D deficiency. Malnutrition, chronic inflammation, vitamin deficiencies, and an imbalance in the muscle-gut axis are just a few of the factors that can lead to sarcopenia. Supplementing the diet with antioxidants, polyunsaturated fatty acids, vitamins, probiotics, prebiotics, proteins, kefir, and short-chain fatty acids could be potential nutritional therapies against sarcopenia. Finally, a personalized integrated strategy to counteract sarcopenia and maintain the health of skeletal muscles is suggested in this review.

Regulation of adipogenesis by exosomal milk miRNA

Milk is a rich source of miRNA packaged in exosomes. Evidence for the systemic uptake and tissue distribution of milk exosomes was reported in newborn and adult humans and animals. Breastfeeding in infants was associated with a reduced risk of obesity. Numerous adipogenesis-related miRNAs have been detected in human milk exosomes. It has been demonstrated that ingested exosomal milk miRNAs may alter gene expression in offspring to regulate their metabolism and growth. In humans, consumption of other species' milk, such as cows and goats, is continued through adulthood. Since miRNAs are conserved, the concern of cross-species transfer of adipogenic miRNA has been raised in recent years, and the increase in obesity worldwide was attributed partially to dairy milk consumption by humans. However, evidence is still weak. Research emphasizes the need for an adequate number of exosomal milk's miRNAs to reach the target cell for biological action to be achieved. It was reported that obese women's milk had less miRNA-148a and miRNA-30b, which may affect the fat acquisition of their babies. Some exosomal milk miRNAs, such as miRNA-29, miRNA-148, miRNA-30b and miRNA-125b, may have epigenetic effects on milk recipients. Moreover, the ability of milk exosomes to cross the gastrointestinal barrier makes them a promising oral drug delivery tool. Yet, exosomes may also be tagged with specific ligands which target certain tissues. Thus, milk exosomes can be engineered and loaded with certain miRNAs responsible for adipocyte differentiation, conversion, or browning. Modifications in the miRNA cargo of exosomes can benefit human health and be an alternative to traditional drugs.

Targeting Nanotechnology and Nutraceuticals in Obesity: An Updated Approach

HYPOTHESIS

This review article represents a brief layout of the risk factors and pathophysiology responsible for obesity, customary treatment strategies, and nanotechnology-based nutraceutical for the therapeutics of obesity.

EXPERIMENTS

An exhaustive search of the literature was done for this purpose, using Google Scholar, PubMed, and ScienceDirect databases. A literature study was conducted using publications published in peer-reviewed journals between 2000 and 2022.

FINDINGS

This was revealed that risk factors responsible for obesity were genetic abnormalities and environmental and socio-economic factors. Several research articles published between 2000 and 2022 were based on phytoconstituents-based nanoformulation for obesity therapeutics and, therefore, have been systematically compiled in this review. Various nutraceuticals like Garcinia cambogia, quercetin, resveratrol, capsaicin, Capsicum, Curcuma longa, Camella Sinensis, Zingiber officinalis, Citrus aurantium, Aegle marmelos, Coffea canephora, Asparagus officinalis, Gardenia jasminoides, Catha edulis, Clusia nemroisa, Rosmarinus officinalis, Cirsium setidens, Betula platyphylla, Tripterygium wilfordi possessing anti-obesity actions are discussed in this review along with their patents, clinical trials as well as their nanoformulation available.

CONCLUSION

This review illustrates that nanotechnology has a great propensity to impart a promising role in delivering phytochemicals and nutraceuticals in managing obesity conditions and other related disorders.

Epigallocatechin gallate (EGCG) attenuates severe acute respiratory coronavirus disease 2 (SARS-CoV-2) infection by blocking the interaction of SARS-CoV-2 spike protein receptor-binding domain to human angiotensin-converting enzyme 2

The outbreak of the coronavirus disease 2019 caused by the severe acute respiratory syndrome coronavirus 2 triggered a global pandemic where control is needed through therapeutic and preventive interventions. This study aims to identify natural compounds that could affect the fusion between the viral membrane (receptor-binding domain of the severe acute respiratory syndrome coronavirus 2 spike protein) and the human cell receptor angiotensin-converting enzyme 2. Accordingly, we performed the enzyme-linked immunosorbent assay-based screening of 10 phytochemicals that already showed numerous positive effects on human health in several epidemiological studies and clinical trials. Among these phytochemicals, epigallocatechin gallate, a polyphenol and a major component of green tea, could effectively inhibit the interaction between the receptor-binding domain of the severe acute respiratory syndrome coronavirus 2 spike protein and the human cell receptor angiotensin-converting enzyme 2. Alternately, in silico molecular docking studies of epigallocatechin gallate and angiotensin-converting enzyme 2 indicated a binding score of −7.8 kcal/mol and identified a hydrogen bond between R393 and angiotensin-converting enzyme 2, which is considered as a key interacting residue involved in binding with the severe acute respiratory syndrome coronavirus 2 spike protein receptor-binding domain, suggesting the possible blocking of interaction between receptor-binding domain and angiotensin-converting enzyme 2. Furthermore, epigallocatechin gallate could attenuate severe acute respiratory syndrome coronavirus 2 infection and replication in Caco-2 cells. These results shed insight into identification and validation of severe acute respiratory syndrome coronavirus 2 entry inhibitors.

Bioactive compounds for neuropathic pain: An update on preclinical studies and future perspectives

Among different types of chronic pain, neuropathic pain (NP), arising from damage to the nervous system, including peripheral fibers and central neurons, is notoriously difficult to treat and affects 7-10% of the general population. Currently available treatment options for NP are limited and opioid analgesics have severe side effects and can result in opioid use disorder. Recent studies have exhibited the role of dietary bioactive compounds in the mitigation of NP. Here, we assessed the effects of commonly consumed bioactive compounds (ginger, curcumin, omega-3 polyunsaturated fatty acids, epigallocatechin gallate, resveratrol, soy isoflavones, lycopene, and naringin) on NP and NP-related neuroinflammation. Cellular studies demonstrated that these bioactive compounds reduce inflammation via suppression of NF-κB and MAPK signaling pathways that regulate apoptosis/cell survival, antioxidant, and anti-inflammatory responses. Animal studies strongly suggest that these regularly consumed bioactive compounds have a pronounced anti-NP effect as shown by decreased mechanical allodynia, mechanical hyperalgesia, thermal hyperalgesia, and cold hyperalgesia. The proposed molecular mechanisms include (1) the enhancement of neuron survival, (2) the reduction of neuronal hyperexcitability by activation of antinociceptive cannabinoid 1 receptors and opioid receptors, (3) the suppression of sodium channel current, and (4) enhancing a potassium outward current in NP-affected animals, triggering a cascade of chemical changes within, and between neurons for pain relief. Human studies administered in this area have been limited. Future randomized controlled trials are warranted to confirm the findings of preclinical efficacies using bioactive compounds in patients with NP.

Benefits of Curcumin in the Vasculature: A Therapeutic Candidate for Vascular Remodeling in Arterial Hypertension and Pulmonary Arterial Hypertension?

Growing evidence suggests that hypertension is one of the leading causes of cardiovascular morbidity and mortality since uncontrolled high blood pressure increases the risk of myocardial infarction, aortic dissection, hemorrhagic stroke, and chronic kidney disease. Impaired vascular homeostasis plays a critical role in the development of hypertension-induced vascular remodeling. Abnormal behaviors of vascular cells are not only a pathological hallmark of hypertensive vascular remodeling, but also an important pathological basis for maintaining reduced vascular compliance in hypertension. Targeting vascular remodeling represents a novel therapeutic approach in hypertension and its cardiovascular complications. Phytochemicals are emerging as candidates with therapeutic effects on numerous pathologies, including hypertension. An increasing number of studies have found that curcumin, a polyphenolic compound derived from dietary spice turmeric, holds a broad spectrum of pharmacological actions, such as antiplatelet, anticancer, anti-inflammatory, antioxidant, and antiangiogenic effects. Curcumin has been shown to prevent or treat vascular remodeling in hypertensive rodents by modulating various signaling pathways. In the present review, we attempt to focus on the current findings and molecular mechanisms of curcumin in the treatment of hypertensive vascular remodeling. In particular, adverse and inconsistent effects of curcumin, as well as some favorable pharmacokinetics or pharmacodynamics profiles in arterial hypertension will be discussed. Moreover, the recent progress in the preparation of nano-curcumins and their therapeutic potential in hypertension will be briefly recapped. The future research directions and challenges of curcumin in hypertension-related vascular remodeling are also proposed. It is foreseeable that curcumin is likely to be a therapeutic agent for hypertension and vascular remodeling going forwards.

Effects of turmeric (Curcuma longa) and its constituent (curcumin) on the metabolic syndrome: An updated review

Metabolic syndrome (MS) involves people with the following risk factors: obesity, hypertension, high glucose level and hyperlipidemia. It can increase the risk of heart disease, stroke and type 2 diabetes mellitus. The prevalence of MS in the world's adult population is about 20%-25%. Today, there is much care to use medicinal plants. Turmeric (Curcuma longa) as well as curcumin which is derived from the rhizome of the plant, has been shown beneficial effects on different components of MS. Thus, the purpose of this manuscript was to introduce different in vitro, in vivo and human studies regarding the effect of turmeric and its constituent on MS. Moreover, different mechanisms of action by which this plant overcomes MS have been introduced. Based on studies, turmeric and its bioactive component, curcumin, due to their anti-inflammatory and antioxidant properties, have antidiabetic effects through increasing insulin release, antihyperlipidemic effects by increasing fatty acid uptake, anti-obesity effects by decreasing lipogenesis, and antihypertensive effects by increasing nitric oxide. According to several in vivo, in vitro and human studies, it can be concluded that turmeric or curcumin has important values as a complementary therapy in MS. However, more clinical trials should be done to confirm these effects.

Beneficial Effects of Bovine Milk Exosomes in Metabolic Interorgan Cross-Talk

Extracellular vesicles are membrane-enclosed secreted vesicles involved in cell-to-cell communication processes, identified in virtually all body fluids. Among extracellular vesicles, exosomes have gained increasing attention in recent years as they have unique biological origins and deliver different cargos, such as nucleic acids, proteins, and lipids, which might mediate various health processes. In particular, milk-derived exosomes are proposed as bioactive compounds of breast milk, which have been reported to resist gastric digestion and reach systemic circulation, thus being bioavailable after oral intake. In the present manuscript, we critically discuss the available evidence on the health benefits attributed to milk exosomes, and we provide an outlook for the potential future uses of these compounds. The use of milk exosomes as bioactive ingredients represents a novel avenue to explore in the context of human nutrition, and they might exert important beneficial effects at multiple levels, including but not limited to intestinal health, bone and muscle metabolism, immunity, modulation of the microbiota, growth, and development.

Effects of medical plants from Zingiberaceae family on cardiovascular risk factors of type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials

We performed a meta-analysis on randomized controlled trials (RCTs) to evaluate the efficacy of Zingiberaceae on cardiovascular risk factors in type 2 diabetes mellitus (T2DM). PubMed, Web of Science, Embase, The Cochrane Library, and Scopus were searched systematically until October 18, 2021. Thirty-four RCTs with 2154 patients met our inclusion. Pooled analysis indicated that Zingiberaceae can significantly improve body weight (BW) (WMD = -1.012, 95% CI: -1.673, -0.351, p = .003), fasting blood glucose (FBG) (WMD = -14.292, 95% CI: -18.588, -9.995, p < .001), glycosylated hemoglobin 1c (HbA1c) (WMD = -0.432, 95% CI: -0.607, -0.257, p < .001), serum insulin (WMD = -2.036, 95% CI: -2.857, -1.216, p < .001), homeostasis model assessment insulin resistance (HOMA-IR) (WMD = -0.886, 95% CI: -1.375, -0.398, p < .001), high density lipoprotein-cholesterol (HDL-C) (WMD = 0.850, 95% CI: 0.018, 1.682, p = .045), triglyceride (TG) (WMD = -17.636, 95% CI: -27.121, -8.151, p < .001), diastolic blood pressure (DBP) (WMD = -0.642, 95% CI: -1.148, -0.137, p = .013), C-reactive protein (CRP) (WMD = -0.623, 95% CI: -1.061, -0.186, p = .005), tumor necrosis factor-α (TNF-α) (WMD = -3.020, 95% CI: -4.327, -1.712, p < .001), and interleukin 6 (IL-6) (WMD = -1.147, 95% CI: -1.887, -0.406, p = .002). The supplementation of Zingiberaceae may be an effective adjunctive therapy in management of T2DM and prevention cardiovascular complications by decreasing BW, improving blood glucose control, insulin resistance, lipid profiles (HDL-C and TG), blood pressure (DBP), and reducing inflammation (CRP, TNF-α, and IL-6). PRACTICAL APPLICATIONS: Approximately half of the deaths of individuals with diabetes mellitus (DM) are attributable to cardiovascular disease (CVD), and individuals with T2DM have a two-fold increased risk of cardiovascular mortality than healthy individuals. Currently, T2DM is mainly treated with hypoglycemic medication such as sulfonylureas, thiazolidinediones, meglitinides, and biguanides. Nevertheless, most of them with long-term usage could cause side effects, including hypoglycemia and gastrointestinal troubles. Several species of the Zingiberaceae family are used in traditional herbal medicines, which have been widely used in traditional and complementary medicine. Proving the potential benefits of Zingiberaceae on T2DM and its cardiovascular complications has positive clinical implications for the use of this practical herb.

The Multifaceted Actions of Curcumin in Obesity

Obesity remains a pervasive health concern worldwide with concomitant comorbidities such as cardiovascular diseases, diabetes, inflammation, and other metabolic disorders. A wealth of data validates dietary and lifestyle modifications such as restricting caloric intake and increasing physical activity to slow the obesity development. Recently, the advent of phytochemicals such as curcumin, the active ingredient in turmeric, has attracted considerable research interest in tracking down their possible effects in protection against obesity and obesity-related comorbidities. According to the existing literature, curcumin may regulate lipid metabolism and suppress chronic inflammation interacting with white adipose tissue, which plays a central role in the complications associated with obesity. Curcumin also inhibits the differentiation of adipocyte and improves antioxidant properties. In the present review, we sought to deliberate the possible effects of curcumin in downregulating obesity and curtailing the adverse health effects of obesity.

Dietary curcumin supplementation promotes browning and energy expenditure in postnatal overfed rats

Background

Early postnatal overfeeding could result in metabolic imprinting that decreases energy expenditure following white adipose tissue (WAT) gain throughout life. This research investigated whether curcumin (CUR) supplementation could promote WAT browning and activate thermogenesis in postnatal overfed rats.

Methods and results

This study adjusted the size of litters to three (small litters, SL) or ten (normal litters, NL) to mimic early postnatal overfeeding or normal feeding from postnatal day 3. From postnatal week 3 (weaning period), SL rats were fed a standard diet (SL) or a diet supplemented with 1% (SL_{1% CUR}) or 2% (SL_{2% CUR}) CUR for ten weeks. At postnatal week 13, SL rats with 1% or 2% CUR supplementation had lower body weight and less WAT gain and had an increased lean mass ratio, and their glucose tolerance and blood lipid levels had recovered to normal when compared to SL rats that did not receive the supplement. Moreover, the increased heat generation were consistent with the expression levels of uncoupling protein 1 (UCP1) and other browning-related genes in the subcutaneous adipose tissue (SAT) of the SL_{2% CUR} rats but not in the SL_{1% CUR} rats. In addition, 2% CUR dietary supplementation enhanced the serum norepinephrine levels in SL rats, with upregulated mRNA levels of β3-adrenergic receptor (β3-AR) in SAT.

Conclusion

Dietary CUR supplementation attenuates body fat gain and metabolic disorders in SL, which might be induced by promoting browning of SAT and energy expenditure. Moreover, the benefits were more obvious in SL with 2% CUR supplementation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-021-00625-5.

Targeting Wnt signaling pathway by polyphenols: implication for aging and age-related diseases

Age is an important risk factor for different diseases. The same mechanisms that promote aging are involved in the development and progression of age-associated diseases. Polyphenols are organic compounds found in fruits and vegetables. Due to their beneficial properties (e.g. antioxidant and anti-inflammatory), polyphenols have been extensively used for treating chronic diseases. To exert their functions, polyphenols target various molecular mechanisms and signaling pathways, such as mTOR, NF-κB, and Wnt/β-catenin. Wnt signaling is a critical pathway for developmental processes. Besides, dysregulation of this signaling pathway has been observed in various diseases. Several investigations have been conducted on Wnt inhibitors at pre-clinical stages, showing promising results. Herein, we review the studies dealing with the role of polyphenols in targeting the Wnt signaling pathways in aging processes and age-associated diseases, including cancer, diabetes, Alzheimer's disease, osteoporosis, and Parkinson's disease.

Curcumin Suppresses the Lipid Accumulation and Oxidative Stress Induced by Benzo[a]pyrene Toxicity in HepG2 Cells

Benzo[a]pyrene (B[a]P) is a potentially hepatotoxic group-1 carcinogen taken up by the body through ingestion of daily foods. B[a]P is widely known to cause DNA and protein damages, which are closely related to cell transformation. Accordingly, studies on natural bioactive compounds that attenuate such chemical-induced toxicities have significant impacts on public health. This study aimed to uncover the mechanism of curcumin, the major curcuminoid in turmeric (Curcuma longa), in modulating the lipid accumulation and oxidative stress mediated by B[a]P cytotoxicity in HepG2 cells. Curcumin treatment reduced the B[a]P-induced lipid accumulation and reactive oxygen spicies (ROS) upregulation and recovered the cell viability. Cytochrome P450 family 1 subfamily A polypeptide 1 (CYP1A1) and Cytochrome P450 subfamily B polypeptide 1 (CYP1B1) downregulation resulting from decreased aryl hydrocarbon receptor (AhR) translocation into nuclei attenuated the effects of B[a]P-induced lipid accumulation and repressed cell viability, respectively. Moreover, the curcumin-induced reduction in ROS generation decreased the nuclear translocation of Nuclear factor erythroid-2-related factor 2 (Nrf2) and the expression of phase-II detoxifying enzymes. These results indicate that curcumin suppresses B[a]P-induced lipid accumulation and ROS generation which can potentially induce nonalcoholic fatty liver disease (NAFLD) and can shed a light on the detoxifying effect of curcumin.

The Effect of Curcumin Supplemsentation on Anthropometric Indices in Overweight and Obese Individuals: A Systematic Review of Randomized Controlled Trials

BACKGROUND

Curcumin is an active molecule present in turmeric and is the main therapeutic compound. There is growing evidence that curcumin could affect various anthropometric indices. We performed a systematic review to evaluate the efficacy of curcumin supplementation on anthropometric indices in obese and overweight individuals.

METHODS

A comprehensive search was conducted in PubMed, Scopus, Web of Science, and Google Scholar from inception up to February 2020 to identify randomized controlled trials investigating the effect of curcumin supplementation on anthropometric indices including body weight, body mass index (BMI), waist circumference (WC), hip circumference (HC), arm circumference (AC), waist-hip ratio (WHR), total body fat (TBF), and visceral fat (VF) in obese and overweight individuals. The Jadad scale was used to assess the quality of the included studies.

RESULT

Twenty-eight randomized controlled trials, comprising 2168 participants, were included in the systematic review. The results of 16 papers indicated that curcumin reduced at least one of the anthropometric indices among individuals with a BMI ≥ 25 kg/m². Nevertheless, 12 articles showed that curcumin supplementation was not effective in any of the measured anthropometric factors. The included trials exhibited substantial heterogeneity in terms of the treatment protocol, follow-up duration, curcumin dosage, and background diseases of the participants.

CONCLUSION

Clinical trials that have independently examined the effects of curcumin in obese or overweight individuals are limited. However, available studies indicate that curcumin has beneficial impacts on various anthropometric indices. Further trials with longer duration of interventions are needed to confirm these findings.

Prebiotic Effect of Berberine and Curcumin Is Associated with the Improvement of Obesity in Mice

Berberine and curcumin, used as food additives or food supplements, possess interesting anti-inflammatory and antioxidant properties. We tested the potential protective effect of both phytochemicals in genetically obese mice and we determined whether these effects can be related to the modulation of gut functions and microbiota. Ob/ob mice were fed a standard diet supplemented with or without 0.1% berberine and/or 0.3% curcumin for 4 weeks. By using targeted qPCR, we found that cecal content of Bifidobacterium spp. and Akkermansia spp. increased mainly upon berberine supplementation. Genes involved in innate immunity (Pla2g2a), mucus production (Muc2) and satietogenic peptide production (Gcg and Pyy) were upregulated in the colon of mice treated with both phytochemicals. Berberine supplementation alone reduced food intake, body weight gain, hypertriglyceridemia and hepatic inflammatory and oxidative stress markers, thus lessening hepatic injury. The increase in Bifidobacterium spp. and Akkermansia spp. was correlated with the improvement of gut barrier function and with the improvement of hepatic inflammatory and oxidative stresses in obese mice. These data support the fact that non-carbohydrate phytochemicals may modulate the gut microbiota in obesity and related gut and hepatic alterations.

Effect of curcuma on zinc, lipid profile and antioxidants levels in blood and tissue of streptozotocin-induced diabetic rats fed zinc deficiency diet

Due to the importance of zinc as an antioxidant and its crucial role in insulin synthesis, its deficiency may affect adversely diabetic state. So, this study aimed to modulate these effects using Curcuma longa as natural antioxidant. Rats were divided into four groups: two groups fed a zinc sufficient diet one non-diabetic and the other diabetic, while the others two groups diabetic rats fed a zinc-deficient diet, one non-treated group and the other treated with curcuma 1% diet. After four weeks of dietary manipulation, fasting animals were scarified. Zinc deficiency decreased body weight, insulin, zinc tissues, alkaline phosphatase, reduced glutathione, glutathione peroxidase, superoxide dismutase and catalase. Conversely glucose, lipids profile, transaminases and malondialdehyde were increased. However, the above-mentioned parameters were significantly improved following curcuma supplementation. So it seems that curcuma is a potent factor for reducing the oxidative severity of zinc deficiency in experimental diabetes through its antioxidants actions.

Natural Bioactive Compounds as Potential Browning Agents in White Adipose Tissue

The epidemic of overweight and obesity underlies many common metabolic diseases. Approaches aimed to reduce energy intake and/or stimulate energy expenditure represent potential strategies to control weight gain. Adipose tissue is a major energy balancing organ. It can be classified as white adipose tissue (WAT) and brown adipose tissue (BAT). While WAT stores excess metabolic energy, BAT dissipates it as heat via adaptive thermogenesis. WAT also participates in thermogenesis by providing thermogenic fuels and by directly generating heat after browning. Browned WAT resembles BAT morphologically and metabolically and is classified as beige fat. Like BAT, beige fat can produce heat. Human adults have BAT-like or beige fat. Recruitment and activation of this fat type have the potential to increase energy expenditure, thereby countering against obesity and its metabolic complications. Given this, agents capable of inducing WAT browning have recently attracted broad attention from biomedical, nutritional and pharmaceutical societies. In this review, we summarize natural bioactive compounds that have been shown to promote beige adipocyte recruitment and activation in animals and cultured cells. We also discuss potential molecular mechanisms for each compound to induce adipose browning and metabolic benefits.

The Effect of Curcumin Supplementation on Anthropometric Measures among Overweight or Obese Adults

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.

The Multi-Faceted Effect of Curcumin in Glioblastoma from Rescuing Cell Clearance to Autophagy-Independent Effects

The present review focuses on the multi-faceted effects of curcumin on the neurobiology glioblastoma multiforme (GBM), with a special emphasis on autophagy (ATG)-dependent molecular pathways activated by such a natural polyphenol. This is consistent with the effects of curcumin in a variety of experimental models of neurodegeneration, where the molecular events partially overlap with GBM. In fact, curcumin broadly affects various signaling pathways, which are similarly affected in cell degeneration and cell differentiation. The antitumoral effects of curcumin include growth inhibition, cell cycle arrest, anti-migration and anti-invasion, as well as chemo- and radio-sensitizing activity. Remarkably, most of these effects rely on mammalian target of rapamycin (mTOR)-dependent ATG induction. In addition, curcumin targets undifferentiated and highly tumorigenic GBM cancer stem cells (GSCs). When rescuing ATG with curcumin, the tumorigenic feature of GSCs is suppressed, thus counteracting GBM establishment and growth. It is noteworthy that targeting GSCs may also help overcome therapeutic resistance and reduce tumor relapse, which may lead to a significant improvement of GBM prognosis. The present review focuses on the multi-faceted effects of curcumin on GBM neurobiology, which represents an extension to its neuroprotective efficacy.

Effects of dietary curcumin on growth, antioxidant capacity, fatty acid composition and expression of lipid metabolism-related genes of large yellow croaker fed a high-fat diet

A 10-week feeding trial was conducted to investigate the effect of dietary curcumin (CC) on growth antioxidant responses, fatty acid composition, and expression of lipid metabolism-related genes of large yellow croaker fed a high-fat diet (HFD). Four diets (lipid level at 18 %) were formulated with different levels of curcumin (0, 0·02, 0·04 and 0·06 %). The best growth performance was found in the 0·04 % curcumin group, with the body and hepatic lipid levels lower than the control group (0 % CC). The content of TAG, total cholesterol and LDL-cholesterol was the least in the 0·06 % curcumin group. The lowest malondialdehyde and the highest superoxide dismutase, catalase and total antioxidant capacity were observed in the 0·04 % curcumin group. The 0·04 % curcumin group had higher expression of Δ6fad, elovl5 and elovl4 and showed higher hepatic n-6 and n-3 PUFA. Expression of ppara, cpt1, and aco was significantly increased, while expression of srebp1 and fas was dramatically decreased in curcumin groups compared with the control group. Overall, 0·04 % curcumin supplementation could mitigate the negative effects caused by HFD and promote growth via reducing hepatic lipid deposition, improving antioxidant activity and increasing PUFA of large yellow croaker. To conclude, abnormal hepatic lipid deposition was probably due to increased fatty acid oxidation and reduced de novo synthesis of fatty acids.

A Curcumin Analog Exhibits Multiple Biologic Effects on the Pathogenesis of Alzheimer's Disease and Improves Behavior, Inflammation, and β-Amyloid Accumulation in a Mouse Model

Drugs for the treatment of Alzheimer’s disease (AD) are in urgent demand due to the unmet need and the social burden associated with the disease. Curcumin has been historically considered as a beneficial product for anti-aging and AD. However, many efforts to develop curcumin for clinical use are hindered mainly due to its poor bioavailability. Recent development in drug delivery and structural design has resolved these issues. In this study, we identified a small molecule, TML-6, as a potential drug candidate for AD through screening a panel of curcumin derivatives using six biomarker platforms related to aging biology and AD pathogenesis. The structural modification of TML-6 is designed to improve the stability and metabolism of curcumin. Cell biological studies demonstrated that TML-6 could inhibit the synthesis of the β-amyloid precursor protein and β-amyloid (Aβ), upregulate Apo E, suppress NF-κB and mTOR, and increase the activity of the anti-oxidative Nrf2 gene. In the 3x-Tg AD animal model, TML-6 treatment resulted in significant improvement in learning, suppression of the microglial activation marker Iba-1, and reduction in Aβ in the brain. Although TML-6 exhibited a greater improvement in bioavailability as compared to curcumin, formulation optimization and toxicological studies are under development to assure its druggability. Taken together, TML-6 meets the current strategy to develop therapeutics for AD, targeting the combination of the Aβ cascade and aging-related biology processes.

The Effect of Curcumin on the Differentiation of Mesenchymal Stem Cells into Mesodermal Lineage

Curcumin has been placed at the forefront of the researcher's attention due to its pleiotropic pharmacological effects and health benefits. A considerable volume of articles has pointed out curcumin's effects on the fate of stem cell differentiation. In this review, a descriptive mechanism of how curcumin affects the outcome of the differentiation of mesenchymal stem cells (MSCs) into the mesodermal lineage-i.e., adipocyte, osteocyte, and chondrocyte differentiation-is compiled from the literature. The sections include the mechanism of inhibition or induction of MSCs differentiation to each lineage, their governing molecular mechanisms, and their signal transduction pathways. The effect of different curcumin doses and its structural modifications on the MSCs differentiation is also discussed.

Efficacy of phospholipidated curcumin in nonalcoholic fatty liver disease: a clinical study

Curcumin is a safe and dietary phytochemical that can improve different pathophysiologic features of non-alcoholic fatty liver disease (NAFLD). Here, we investigated the efficacy of phospholipidated curcumin supplementation in NAFLD patients. In this single-arm study, 36 patients were recruited. Each patient received three capsules a day (each containing 500 mg of phospholipidated curcumin [overall content of curcuminoids per capsule: 100 mg]) for a period of 8 weeks. The results indicated that phospholipidated curcumin supplementation reduced NAFLD severity and ameliorated ultrasonographic and biochemical measures (including liver transaminases and lipid profile) associated with disease progression.

Effect of Curcumin and α-Lipoic Acid in Attenuating Weight Gain and Adiposity

Objective: Obesity is growing at epidemic proportions worldwide. Natural compounds curcumin and α-lipoic acid have been shown to reduce body-weight gain in both preclinical and clinical studies. This study examined the effect of a combination of curcumin and α-lipoic acid on weight gain and adiposity in high-fat-diet (HFD)-fed mice. Methods: C57BL6 mice (7 weeks old) were randomly assigned to receive either HFD (60% fat) or a normal diet (ND, 10% fat) for a 12-week period, following which the mice receiving HFD were further assigned to supplemental curcumin (0.07%), α-lipoic acid (0.2%), or a combination of curcumin and α-lipoic acid formulated into the HFD for a further 12 weeks. Food intake and body mass were determined on a weekly basis. Body fat composition was determined by dual energy X-ray absorptiometry. Results: Treatment with both curcumin and α-lipoic acid significantly reduced body weight gain in HFD-treated mice, and the combination was more effective in attenuating body weight compared to the individual agents. Food intake and caloric intake were significantly lower in the mice that received α-lipoic acid. Percentage body fat and fat mass and lean body mass, which were increased following HFD feeding, were attenuated in the mice receiving curcumin and the combination. Lean mass was also elevated in the mice that were subjected to an HFD, which was unaltered by curcumin or the combination. Conclusions: Taken together, the combination of curcumin and α-lipoic acid exhibits an additive effect in reducing weight gain and adiposity in response to high-fat feeding.

Does Turmeric/curcumin Supplementation Change Anthropometric Indices in Patients with Non-alcoholic Fatty Liver Disease? A Systematic Review and Meta-analysis of Randomized Controlled Trials

Curcumin is the principal polylphenol of turmeric that has been used to treat various disorders. However, its anti-obesity effects in patients with non-alcoholic fatty liver disease (NAFLD) remain controversial. Therefore, we aimed to perform a meta-analysis on the effects of supplementation with turmeric/curcumin on body weight, body mass index (BMI) and waist circumference (WC) in these patients. PubMed, Scopus, Cochrane Library, and ISI Web of Science were searched until January 2019, without any restrictions. Clinical trials that reported body weight, BMI and WC in patients with NAFLD were included. Weighted mean differences (WMDs) were pooled using a random-effects model. Eight studies (449 participants) fulfilled the eligibility criteria of the present meta-analysis. Overall, meta-analysis could not show any beneficial effect of turmeric/curcumin supplementation on body weight (WMD, -0.54 kg; 95% confidence interval [CI], -2.40, 1.31; p = 0.56; I2 = 0.0%), BMI (WMD, -0.21 kg/m2; 95% CI, -0.71, 0.28; p = 0.39; I2 = 0.0%) and WC (WMD, -0.88 cm; 95% CI, -3.76, 2.00; p = 0.54; I2 = 0.0%). Subgroup analysis based on participants' baseline BMI, type of intervention, and study duration did not show any significant association in all subgroups. The results showed that turmeric/curcumin supplementation had no significant effect on body weight, BMI and WC in patients with NAFLD. Further studies with large-scale are needed to find out possible anti-obesity effects of turmeric/curcumin.

Nanoencapsulation of functional food ingredients

Many functional food ingredients are poorly soluble in water, susceptible to chemical degradation, and incompatible with surrounding food matrix. Other issues are related to limited oral bioavailability, unpleasant sensory properties, and poor release profiles. Nanoencapsulation of functional food ingredients can help increase their water solubility/dispersibility in foods and beverages, improve their bioavailability by exhibiting good dose-dependent functionalities, mask undesired flavors/tastes to reduce the adverse effect on mouth-feel, enhance shelf-life and compatibility during production, storage, transportation and utilization of food products, and control release rate or specific delivery environment for better performance on their functionalities. This chapter provides an overview of different delivery systems for different functional food ingredients, the types of materials suitable for wall materials or building blocks of nanocapsules, the fabrication methods to assemble different delivery systems and release these active ingredients under different physiological conditions.

Demethoxycurcumin: A naturally occurring curcumin analogue for treating non-cancerous diseases

Turmeric extracts contain three primary compounds, which are commonly referred to as curcuminoids. They are curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin. While curcumin has been the most extensively studied of the curcuminoids, it suffers from low overall oral bioavailability due to extremely low absorption as a result of low water solubility and instability at acidic pH, as well as rapid metabolism and clearance from the body. However, DMC, which lacks the methoxy group on the benzene ring of the parent structure, has much greater chemical stability at physiological pH and has been recently reported to exhibit antitumor properties. However, the treatment of noncancerous diseases with DMC has not been comprehensively reviewed. Therefore, here we evaluate published scientific literature on the therapeutic properties of DMC. The beneficial pharmacological actions of DMC include anti-inflammatory, neuroprotective, antihypertensive, antimalarial, antimicrobial, antifungal, and vasodilatory properties. In addition, DMC's ability to ameliorate the effects of free radicals and an environment characterized by oxidative stress caused by the accumulation of advanced glycation end-products associated with diabetic nephropathy, as well as DMC's capacity to inhibit the migration and proliferation of vascular smooth muscle cells following balloon angioplasty are also addressed. This review collates the available literature regarding the therapeutic possibilities of DMC in noncancerous conditions.

Effect of turmeric on glycemic status, lipid profile, hs-CRP, and total antioxidant capacity in hyperlipidemic type 2 diabetes mellitus patients

Diabetes mellitus is the most common metabolic disorder worldwide. This study examined the effect of turmeric supplementation on glycemic status, lipid profile, hs-CRP and total antioxidant capacity in hyperlipidemic type 2 diabetic patients. In this double-blind, randomized clinical trial, 80 hyperlipidemic type 2 diabetic patients were divided into turmeric (2,100 mg powdered rhizome of turmeric daily) and placebo groups for 8 weeks. Body weight, fasting plasma glucose, hemoglobin A1c (HbA1c), serum insulin, triglyceride (TG), total cholesterol, low density lypoprotein cholesterol (LDL-c), high density lypoprotein cholesterol, apolipoprotein A1, apolipoprotein B, high sensitivity C-reactive protein (hs-CRP), and total antioxidant capacity were measured before and after intervention. Statistical analysis was carried out using paired and independent t and chi-square tests. Seventy five patients completed the study. The turmeric group showed significant decreases in body weight, TG, and LDL-c compared with baseline (p value < 0.05). Body mass index, TG, and total cholesterol decreased significantly in the turmeric group compared with the placebo group (p value < 0.05). No significant changes were observed in other parameters between the two groups after intervention (p value < 0.05). Turmeric improved some fractions of lipid profile and decreased body weight in hyperlipidemic patients with type 2 diabetes. It had no significant effect on glycemic status, hs-CRP, and total antioxidant capacity in these patients.

Cellular and molecular mechanisms of curcumin in prevention and treatment of disease

Curcumin is a naturally occurring polyphenolic compound present in rhizome of Curcuma longa belonging to the family zingiberaceae. Growing experimental evidence revealed that curcumin exhibit multitarget biological implications signifying its crucial role in health and disease. The current review highlights the recent progress and mechanisms underlying the wide range of pharmacological effects of curcumin against numerous diseases like neuronal, cardiovascular, metabolic, kidney, endocrine, skin, respiratory, infectious, gastrointestinal diseases and cancer. The ability of curcumin to modulate the functions of multiple signal transductions are linked with attenuation of acute and chronic diseases. Numerous preclinical and clinical studies have revealed that curcumin modulates several molecules in cell signal transduction pathway including PI3K, Akt, mTOR, ERK5, AP-1, TGF-β, Wnt, β-catenin, Shh, PAK1, Rac1, STAT3, PPARγ, EBPα, NLRP3 inflammasome, p38MAPK, Nrf2, Notch-1, AMPK, TLR-4 and MyD-88. Curcumin has a potential to prevent and/or manage various diseases due to its anti-inflammatory, anti-oxidant and anti-apoptotic properties with an excellent safety profile. In contrast, the anti-cancer effects of curcumin are reflected due to induction of growth arrest and apoptosis in various premalignant and malignant cells. This review also carefully emphasized the pharmacokinetics of curcumin and its interaction with other drugs. Clinical studies have shown that curcumin is safe at the doses of 12 g/day but exhibits poor systemic bioavailability. The use of adjuvant like piperine, liposomal curcumin, curcumin nanoparticles and curcumin phospholipid complex has shown enhanced bioavailability and therapeutic potential. Further studies are warranted to prove the potential of curcumin against various ailments.

The effect of curcumin supplementation on anthropometric indices, insulin resistance and oxidative stress in patients with type 2 diabetes: a randomized, double-blind clinical trial

BACKGROUND

Diabetes mellitus is a common metabolic disorders in human and affect a lot of people around the world. Curcumin is a component of turmeric and in many studies therapeutic effects such as anti-hypertensive, anti-hyperlipidemia, anti-hyperglycemia for this substance are shown.

AIM

The aim of this study was to investigate the effect of curcumin supplementation on anthropometric indices glycemic control and oxidative stress in overweight patients with type 2 diabetes.

MATERIALS AND METHODS

In this randomized, double-blind, placebo-controlled trial, 53 participants with type 2 diabetes were divided randomly into the experimental and control groups to receive either 1500 mg curcumin or placebo capsule three times in a day for 10 weeks.

RESULT

Supplementation with curcumin in type 2 diabetes compare to placebo causes a significant changes in mean weight (- 0.64 ± 0.22 vs. 0.19 ± 0.37 p < 0.05), body mass index (BMI) (0.3 ± 0.03 vs. 0.1 ± 0 p < 0.05), waist circumference (WC) (- 1.2 ± 0.4 vs. - 0.43 ± 0.11 p < 0.05) and fasting blood sugar (FBS) (- 7 ± 2 vs. 3 ± 0.2 p < 0.05) but did not show any difference for hemoglobin A1c (HbA1c), insulin, malondialdehyde (MDA), total antioxidant capacity (TAC), Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) and pancreatic B cell function (HOMA-B) at end of study.

CONCLUSION

This study indicated that daily administration of 1500 mg curcumin has positive effects in reducing fasting blood glucose and weight in patients with type 2 diabetes.Trial registration NCT02529982. Registered 19 August 2015, http://www.clinicaltrial.gov.

Dietary polyphenols and their roles in fat browning

Discovery of the presence of brown adipose tissue (BAT) in newborn babies and adult humans, especially constitutively active brown fat or inducible beige fat, has led to the investigation of strategies employing BAT aimed at the development of novel therapeutic avenues for combating obesity and diabetes. Such antiobesity therapeutic tools include pharmaceutical and nutraceutical dietary polyphenols. Although there have been emerging notable advances in knowledge of and an increased amount of research related to brown and beige adipocyte developmental lineages and transcriptional regulators, current knowledge regarding whether and how food factors and environmental modifiers of BAT influence thermogenesis has not been extensively investigated. Therefore, in this review, we summarized recent updates on the exploration of dietary polyphenols while paying attention to the activation of BAT and thermogenesis. Specifically, we summarized findings pertaining to BAT metabolism, white adipose tissue (WAT) browning and thermogenic function of polyphenols (e.g., flavan-3-ols, green tea catechins, resveratrol, capsaicin/capsinoids, curcumin, thymol, chrysin, quercetin and berberine) that may foster a relatively safe and effective therapeutic option to improve metabolic health. We also deciphered the underlying proposed mechanisms through which these dietary polyphenols facilitate BAT activity and WAT browning. Characterization of thermogenic dietary factors may offer novel insight enabling revision of nutritional intervention strategies aimed at obesity and diabetes prevention and management. Moreover, identification of polyphenolic dietary factors among plant-derived natural compounds may provide information that facilitates nutritional intervention strategies against obesity, diabetes and metabolic syndrome.

Curcumin and dietary polyphenol research: beyond drug discovery

Numerous natural products available over the counter are commonly consumed by healthy, sub-healthy or ill people for the treatment and prevention of various chronic diseases. Among them, a few dietary polyphenols, including the curry compound curcumin, have been attracting the most attention from biomedical researchers and drug developers. Unlike many so-called "good drug candidates", curcumin and several other dietary polyphenols do not have a single known therapeutic target or defined receptor. In addition, the bioavailability of these polyphenols is usually very low due to their poor absorption in the gut. These recently debated features have created enormous difficulties for drug developers. In this review, I do not discuss how to develop curcumin, other dietary polyphenols or their derivatives into pharmaceutical agents. Instead, I comment on how curcumin and dietary polyphenol research has enriched our knowledge of insulin signaling, including the presentation of my perspectives on how these studies will add to our understanding of the famous hepatic insulin function paradox.

Efficacy of curcumin for age-associated cognitive decline: a narrative review of preclinical and clinical studies

Processes such as aberrant redox signaling and chronic low-grade systemic inflammation have been reported to modulate age-associated pathologies such as cognitive impairment. Curcumin, the primary therapeutic component of the Indian spice, Turmeric (Curcuma longa), has long been known for its strong anti-inflammatory and antioxidant activity attributable to its unique molecular structure. Recently, an interest in this polyphenol as a cognitive therapeutic for the elderly has emerged. The purpose of this paper is to critically review preclinical and clinical studies that have evaluated the efficacy of curcumin in ameliorating and preventing age-associated cognitive decline and address the translational progress of preclinical to clinical efficacy. PubMed, semantic scholar, and Google scholar searches were used for preclinical studies; and clinicaltrials.gov , the Australian and New Zealand clinical trials registry, and PubMed search were used to select relevant completed clinical studies. Results from preclinical studies consistently demonstrate curcumin and its analogues to be efficacious for various aspects of cognitive impairment and processes that contribute to age-associated cognitive impairment. Results of published clinical studies, while mixed, continue to show promise for curcumin's use as a therapeutic for cognitive decline but overall remain inconclusive at this time. Both in vitro and in vivo studies have found that curcumin can significantly decrease oxidative stress, systemic inflammation, and obstruct pathways that activate transcription factors that augment these processes. Future clinical studies would benefit from including evaluation of peripheral and cerebrospinal fluid biomarkers of dementia and behavioral markers of cognitive decline, as well as targeting the appropriate population.