Evaluation of the effect of curcumin capsules on glyburide therapy in patients with type-2 diabetes mellitus

Design and evaluation of curcumin-derived aldopentose compounds: Unlocking their antidiabetic potential through integrative in vitro, in vivo, and in silico studies on carbohydrate-degrading enzymes

Natural polyphenol compounds such as curcumin can inhibit carbohydrate-hydrolyzing enzymes, which may offer an alternative to expensive and potentially side-effect-inducing α-glucosidase inhibitors like acarbose. Hence, this study carried out the synthesis of curcumin aldopentose derivatives, examining their capacity to inhibit the α-glucosidase and α-amylase enzymes with the aim to alleviate hyperglycemia. Initially, the aldopentose derivatives from curcumin were synthesized and confirmed by spectroscopic methods such as MS, 13CNMR, 1HNMR, and FTIR. Afterward, we investigated the inhibitory effects of all derivatives on the α-amylase and α-glucosidase enzymes spectroscopically and determined their inhibition mechanism. We assessed the antioxidant activity and the stability of the synthetic derivatives in the simulated intestinal environment. Finally, we measured the postprandial blood glucose level after administering saturated starch in vivo. The modified compounds showed improved inhibitory effects compared to curcumin alone, with compound C3 demonstrating particularly strong enzyme inhibition. However, when compared with acarbose, a known commercial antidiabetic drug, the synthetic compounds showed lower inhibitory activity against both enzymes, resulting in fewer side effects related to undigested polysaccharides in the gut. Molecular docking studies show introducing a pentose moiety to the curcumin backbone enhanced docking affinities toward both enzymes and subsequently altered the associated IC50 and Ki values. Overall, compound C3 has the potential to be an inhibitor of carbohydrate-degrading enzymes and can effectively reduce glucose absorption in vivo. Given its antioxidant capabilities and reasonable stability, the compound in question shows promises as a potent derivative for the development of new anti-hyperglycemic drugs in future research endeavours.

Enhancing growth, antioxidant capacity, and immune response in tilapia (Oreochromis niloticus) through curcumin supplementation across varied stocking density paradigms

The present study evaluated the effects of curcumin on growth, immune and antioxidant response in tilapia (Oreochromis niloticus). An optimum dose of curcumin was investigated by feeding four different levels of this compound in combination with three different regimes of stocking density (12 treatments). Fish were reared at three densities; low density (LD = 1.50 kg/m3), medium density (MD = 3.00 kg/m3), and high density (HD = 4.50 kg/m3). Each treatment was fed with four different levels of dietary supplementation of curcumin (C0 = 0 mg/kg, C1 = 50 mg/kg, C2 = 100 mg/kg, and C3 = 150 mg/kg) for 60 days. Each treatment has three replicates (n = 50/replicate in LD, 100/replicate in MD, 150/ replicate in HD). Although better growth was observed in MD, however treatments at all densities fed with C1 diet showed improved growth as compared to other diets. Chemical composition of fish and activity of amylase, lipase and protease in all treatments were noted to be similar. Levels of antioxidant enzymes (catalase, superoxide dismutase and glutathione peroxidase) and cortisol in MD and HD treatments were similar to those in LD treatment. However, fish fed with C1 diet in each density treatment showed the lowest values of antioxidant enzymes. Similarly, the levels of malondialdehyde were noted to be similar in MD and HD treatments as compared to that in LD. Its levels were lower in fish fed with C1 and C3 diets in all density treatments. Expression of pro-opiomelanocortin-α (POMC-α), Somatostatins-1 (SST-1) and Interleukin 1-β (IL-1β) did not increase in MD and HD treatments in response to high stocking density when compared with LD treatment. The lowest levels of these genes were noted in fish fed with C2 and C3 diets in all treatments. In conclusion, supplementation of curcumin in diet of tilapia improved growth and antioxidant response in tilapia. optimum dose of curcumin for tilapia culture is 50 mg/kg at the density of 3.00 kg/m3which might be further investigated for intensive culture.

Natural Product Use Among Veterans with Chronic Pain: A Qualitative Study of Attitudes and Communication with Healthcare Providers

BACKGROUND

Despite mixed evidence regarding the safety and efficacy of natural products, many are marketed for pain and related symptoms. Use of these products is prevalent among veterans, who have disproportionately high rates of chronic pain. To date, however, there is limited research on veterans' beliefs and attitudes about natural products and their communication with healthcare providers about their natural product use.

OBJECTIVE

To explore how veterans experiencing chronic pain make decisions about natural product use, to investigate veterans' beliefs about the safety and efficacy of these products, and to examine veterans' experiences discussing natural products with their providers.

DESIGN

Qualitative sub-study conducted as a supplement to a pragmatic randomized controlled trial for chronic pain management.

PARTICIPANTS

Twenty veterans experiencing chronic pain who reported using natural products for pain management or related health concerns.

APPROACH

Qualitative interviews with veterans were conducted over the phone and audio-recorded. Interviews were guided by an original semi-structured interview guide and qualitative data were analyzed using a template-based rapid analysis technique.

KEY RESULTS

Veterans with chronic pain may perceive natural products as safer than pharmaceutical products and may prefer to use natural products. Talking with providers about natural products is important to veterans, who would like information regarding the safety and potential for interaction of natural products with pharmaceutical products. However, veterans were frequently disappointed with these conversations. Veterans felt their providers demonstrated biases against natural products, which negatively impacted patient-provider relationships.

CONCLUSIONS

Veterans wish to have more productive conversations with providers about natural products. They value providers' open-mindedness towards natural products and transparency about limitations in their knowledge. Suggestions for how providers and healthcare systems might better support veterans interested in natural products are discussed.

NF-κB pathway as a molecular target for curcumin in diabetes mellitus treatment: Focusing on oxidative stress and inflammation

Diabetes mellitus (DM) is a collection of metabolic disorder that is characterized by chronic hyperglycemia. Recent studies have demonstrated the crucial involvement of oxidative stress (OS) and inflammatory reactions in the development of DM. Curcumin (CUR), a natural compound derived from turmeric, exerts beneficial effects on diabetes mellitus through its interaction with the nuclear factor kappa B (NF-κB) pathway. Research indicates that CUR targets inflammatory mediators in diabetes, including tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6), by modulating the NF-κB signaling pathway. By reducing the expression of these inflammatory factors, CUR demonstrates protective effects in DM by improving pancreatic β-cells function, normalizing inflammatory cytokines, reducing OS and enhancing insulin sensitivity. The findings reveal that CUR administration effectively lowered blood glucose elevation, reinstated diminished serum insulin levels, and enhanced body weight in Streptozotocin -induced diabetic rats. CUR exerts its beneficial effects in management of diabetic complications through regulation of signaling pathways, such as calcium-calmodulin (CaM)-dependent protein kinase II (CaMKII), peroxisome proliferator-activated receptor gamma (PPAR-γ), NF-κB, and transforming growth factor β1 (TGFB1). Moreover, CUR reversed the heightened expression of inflammatory cytokines (TNF-α, Interleukin-1 beta (IL-1β), IL-6) and chemokines like MCP-1 in diabetic specimens, vindicating its anti-inflammatory potency in counteracting hyperglycemia-induced alterations. CUR diminishes OS, avert structural kidney damage linked to diabetic nephropathy, and suppress NF-κB activity. Furthermore, CUR exhibited a protective effect against diabetic cardiomyopathy, lung injury, and diabetic gastroparesis. Conclusively, the study posits that CUR could potentially offer therapeutic benefits in relieving diabetic complications through its influence on the NF-κB pathway.

Combined supplementation with hesperidin, phytosterols and curcumin decreases adiposity and improves metabolic health in ovariectomized rats

In recent years many women have looked for alternative therapies to address menopause. Hesperidin, phytosterols and curcumin are bioactive compounds that can ameliorate some cardiovascular risk factors associated with menopause, although there are no data concerning the effects of their combined supplementation. We used ovariectomized (OVX) rats, a postmenopausal model with oestrogen deficiency, to evaluate whether supplementation with a multi-ingredient (MI) including hesperidin, phytosterols and curcumin for 57 days would display beneficial effects against fat mass accretion and metabolic disturbances associated with menopause. Twenty OVX rats were orally supplemented with either MI (OVX-MI) or vehicle (OVX). Furthermore, 10 OVX rats orally received the vehicle along with subcutaneous injections of 17β-oestradiol biweekly (OVX-E2), whereas 10 rats were sham operated and received oral and injected vehicles (control group; SH). MI supplementation partly counteracted the fat mass accretion observed in OVX animals, which was evidenced by decreased total fat mass, adiposity index, the weight of retroperitoneal, inguinal and mesenteric white adipose tissue (MWAT) depots and MWAT adipocyte hypertrophy. These effects were accompanied by a significant decrease in the circulating levels of leptin and the mRNA levels of the fatty acid uptake-related genes Lpl and Cd36 in MWAT. These results were very similar to those observed in OVX-E2 animals. OVX-MI rats also displayed a higher lean body mass, lean/fat mass ratio, adiponectin-to-leptin ratio and insulin sensitivity than their OVX counterparts. Our findings can pave the way for using this MI formulation as an alternative therapy to manage obesity and to improve the cardiometabolic health of menopausal women.

The effect of curcumin and high-content eicosapentaenoic acid supplementations in type 2 diabetes mellitus patients: a double-blinded randomized clinical trial

BACKGROUND/OBJECTIVES

The present study investigated the effect of curcumin and eicosapentaenoic acid, as one the main components of omega-3 polyunsaturated fatty acids, on anthropometric, glucose homeostasis, and gene expression markers of cardio-metabolic risk in patients with type 2 diabetes mellitus.

SUBJECTS/METHODS

This clinical trial was conducted at the Endocrinology Clinic of Imam Reza Hospital in Tabriz. It aimed to determine the impact of Eicosapentaenoic Acid (EPA), Docosahexaenoic Acid (DHA), and curcumin supplements on various health indicators in patients with Type 2 Diabetes Mellitus (DM2) from 2021.02.01 to 2022.02.01. The study was a randomized double-blinded clinical trial and conducted over 12 weeks with 100 participants randomly divided into four groups. Stratified randomization was used to assign participants to two months of supplementation based on sex and Body Mass Index (BMI). The study comprised four groups: Group 1 received 2 capsules of 500 mg EPA and 200 mg DHA, along with 1 nano-curcumin placebo; Group 2 received 1 capsule of 80 mg nano-curcumin and 2 omega 3 Fatty Acids placebos; Group 3 received 2 capsules of 500 mg EPA and 200 mg DHA, and 1 capsule of 80 mg nano-curcumin; Group 4, the control, received 2 omega 3 Fatty Acids placebos and 1 nano-curcumin placebo.

RESULTS

After twelve weeks of taking EPA + Nano-curcumin supplements, the patients experienced a statistically significant reduction in insulin levels in their blood [MD: -1.44 (-2.70, -0.17)]. This decrease was significantly greater than the changes observed in the placebo group [MD: -0.63 (-1.97, 0.69)]. The EPA + Nano-curcumin group also showed a significant decrease in High-Sensitivity C-Reactive Protein (hs-CRP) levels compared to the placebo group (p < 0.05). Additionally, the EPA + Nano-curcumin group had a significant increase in Total Antioxidant Capacity (TAC) levels compared to the placebo group (p < 0.01). However, there were no significant differences in Fasting Blood Sugar (FBS), Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) index, Quantitative Insulin Sensitivity Check Index (QUICKI), or Hemoglobin A1c (HbA1C) levels between the four groups (all p > 0.05). There were significant differences between the Nano-curcumin and EPA groups [MD: -17.02 (-32.99, -1.05)], and between the Nano-curcumin and control groups [MD: -20.76 (-36.73, -4.79)] in terms of lowering the serum cholesterol level. The difference in Triglycerides (TG) serum levels between the EPA + Nano-curcumin and placebo groups were not statistically significant (p = 0.093). The Nano-curcumin group showed significant decreases in Low-Density Lipoprotein (LDL) levels compared to the EPA group [MD: -20.12 (-36.90, -3.34)] and the control group [MD: -20.79 (-37.57, -4.01)]. There was a near-to-significant difference in High-Density Lipoprotein (HDL) serum levels between the EPA + Nano-curcumin and EPA groups (p = 0.056). Finally, there were significant differences in the decrease of serum Vascular Endothelial Growth Factor (VEGF) levels between the EPA and Nano-curcumin groups [MD: -127.50 (-247.91, -7.09)], the EPA and placebo groups [MD: 126.25 (5.83, 246.66)], the EPA + Nano-curcumin and Nano-curcumin groups [MD: -122.76 (-243.17, -2.35)], and the EPA + Nano- curcumin and placebo groups [MD: 121.50 (1.09, 241.92)].

CONCLUSIONS

The findings of the present study suggest that 12-week supplementation with EPA and Nano-curcumin may positively impact inflammation, oxidative stress, and metabolic parameters in patients with diabetes. The supplementation of EPA and Nano-curcumin may be a potential intervention to manage diabetes and reduce the risk of complications associated with diabetes. However, further research is needed to validate the study's findings and establish the long-term effects of EPA and Nano-curcumin supplementation in patients with diabetes.

Effect of curcumin on painful symptoms of endometriosis: A triple-blind randomized controlled trial

Endometriosis is one of the most common gynecological disorders. This study aimed to determine the effect of curcumin on painful symptoms of endometriosis and the quality of life in affected women. This randomized controlled trial was conducted on 68 women with endometriosis referred to Shahid Beheshti Infertility Center in Isfahan, Iran, 2022. The participants were allocated to intervention (n = 34) and control (n = 34) groups by the blocked randomization method. Curcumin capsules with a dose of 500 mg were given to the intervention group twice a day for 8 weeks, and the placebo with the same dose was given to the control group. The questionnaires of Endometriosis Health Profile, painful symptoms of endometriosis, and visual analogue scale were used to collect data. Independent t, ANCOVA, and Mann-Whitney U-tests were used to compare the outcomes between the study groups. After the intervention, based on the ANCOVA with the adjusting of the baseline values and Mann-Whitney U-test, there was no statistically significant difference in the amounts of usual pain (p = 0.496) and pain at its worst (p = 0.320), quality of life (p = 0.556), and visual pain (p = 0.845). The results showed that using curcumin does not affect the painful symptoms and quality of life of women with endometriosis. Future clinical trials are needed to investigate and highlight the role of curcumin in endometriosis.

Nrf2 modulates the benefits of evening exercise in type 2 diabetes

Exercise has well-characterized therapeutic benefits in the management of type 2 diabetes mellitus (T2DM). Most of the beneficial effects of exercise arise from the impact of nuclear factor erythroid 2 related factor-2 (Nrf2) activation of glucose metabolism. Nrf2 is an essential controller of cellular anti-oxidative capacity and circadian rhythms. The circadian rhythm of Nrf2 is influenced by circadian genes on its expression, where the timing of exercise effects the activation of Nrf2 and the rhythmicity of Nrf2 and signaling, such that the timing of exercise has differential physiological effects. Exercise in the evening has beneficial effects on diabetes management, such as lowering of blood glucose and weight. The mechanisms responsible for these effects have not yet been associated with the influence of exercise on the circadian rhythm of Nrf2 activity. A better understanding of exercise-induced Nrf2 activation on Nrf2 rhythm and signaling can improve our appreciation of the distinct effects of morning and evening exercise. This review hypothesizes that activation of Nrf2 by exercise in the morning, when Nrf2 level is already at high levels, leads to hyperactivation and decrease in Nrf2 signaling, while activation of Nrf2 in the evening, when Nrf2 levels are at nadir levels, improves Nrf2 signaling and lowers blood glucose levels and increases fatty acid oxidation. Exploring the effects of Nrf2 activators on rhythmic signaling could also provide valuable insights into the optimal timing of their application, while also holding promise for timed treatment of type 2 diabetes.

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.

The Efficacy of Nigella sativa L. and Curcumin Nanomicelle Alone or Together on Lipid Profile, Glycemic Control Indices, and Serum 17-Β Estradiol in Postmenopausal Women

Introduction

Menopause is a condition for metabolic disorders. This study aimed to evaluate the effect of Nigella sativa (NS), curcumin nanomicelle (CN), lipid profile, glycemic status and 17-β estradiol (ES) levels in postmenopausal women.

Methods

Triple-blind randomized clinical trial was conducted on 120 postmenopausal women. Participants were randomly assigned to four groups: 1) NS capsule 1000 mg and CN placebo, 2) 80 mg CN capsule and NS placebo, 3) both NS and CN capsules and 4) NS and CN placebo. Participants received a single dose daily for 6 months. The serum lipid profile, glycemic control biomarkers, and ES were measured pre-and post-intervention using biochemical methods.

Results

Total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, fasting blood sugar (FBS), fasting insulin (FI), insulin resistance (IR), and ES showed significant improvement in NS group. CN significantly reduced TC, FI, and IR, and significantly increased ES. The combination of NS-CN significantly decreased TC, LDL, FI, and IR, and increased HDL and ES. The comparison of the studied with the placebo groups showed that these changes were significant in glycemic indices and NS significantly increased estrogen.

Conclusion

NS, CN and NS-CN improved lipid profiles, blood sugar, and hormone levels. However, this improvement was significant in glycemic indices and estrogen levels compared to the placebo group. No superiority of combined NS-CN over NS or CN was found in this trial.

Phytochemicals for the treatment of metabolic diseases: Evidence from clinical studies

With the continuous improvement of people's living standard, the incidence of metabolic diseases is gradually increasing in recent years. There is growing interest in finding drugs to treat metabolic diseases from natural compounds due to their good efficacy and limited side effects. Over the past few decades, many phytochemicals derived from natural plants, such as berberine, curcumin, quercetin, resveratrol, rutin, and hesperidin, have been shown to have good pharmacological activity against metabolic diseases in preclinical studies. More importantly, clinical trials using these phytochemicals to treat metabolic diseases have been increasing. This review comprehensively summarizes the clinical progress of phytochemicals derived from natural plants in the treatment of several metabolic diseases, including type 2 diabetes mellitus (T2DM), obesity and non-alcoholic fatty liver disease (NAFLD). Accumulating clinical evidence shows that a total of 18 phytochemicals have good therapeutic effects on the three metabolic diseases by lowering blood glucose and lipid levels, reducing insulin resistance, enhancing insulin sensitivity, increasing energy expenditure, improving liver function, and relieving inflammation and oxidative stress. The information will help us better understand the medicinal value of these phytochemicals and promote their clinical application in the treatment of metabolic diseases.

The impact of curcumin on migraine: A comprehensive review

Migraine, a neurovascular condition, is a chronic and lifelong disease that affects about 15% of the population worldwide. Although the exact pathophysiology and etiology of migraine are still unclear, oxidative stress, inflammation, and neuroendocrine imbalances are identified as the critical risk factors for migraine attacks. Curcumin is an active component and a polyphenolic diketone compound extracted from turmeric. Curcumin is a promising candidate for preventing and controlling migraine due to its anti‑inflammatory, antioxidative, anti-protein aggregate, and analgesic effects. In the present review, we have evaluated experimental and clinical studies investigating the impact of liposomal curcumin and nano-curcumin on the frequency and severity of migraine attacks in patients. Although the results are promising, more studies should be conducted in this area to show the exact efficacies of curcumin on clinical symptoms of migraine and investigate its potential mechanisms.

Food Polyphenols and Type II Diabetes Mellitus: Pharmacology and Mechanisms

Type II diabetes mellitus and its related complications are growing public health problems. Many natural products present in our diet, including polyphenols, can be used in treating and managing type II diabetes mellitus and different diseases, owing to their numerous biological properties. Anthocyanins, flavonols, stilbenes, curcuminoids, hesperidin, hesperetin, naringenin, and phenolic acids are common polyphenols found in blueberries, chokeberries, sea-buckthorn, mulberries, turmeric, citrus fruits, and cereals. These compounds exhibit antidiabetic effects through different pathways. Accordingly, this review presents an overview of the most recent developments in using food polyphenols for managing and treating type II diabetes mellitus, along with various mechanisms. In addition, the present work summarizes the literature about the anti-diabetic effect of food polyphenols and evaluates their potential as complementary or alternative medicines to treat type II diabetes mellitus. Results obtained from this survey show that anthocyanins, flavonols, stilbenes, curcuminoids, and phenolic acids can manage diabetes mellitus by protecting pancreatic β-cells against glucose toxicity, promoting β-cell proliferation, reducing β-cell apoptosis, and inhibiting α-glucosidases or α-amylase. In addition, these phenolic compounds exhibit antioxidant anti-inflammatory activities, modulate carbohydrate and lipid metabolism, optimize oxidative stress, reduce insulin resistance, and stimulate the pancreas to secrete insulin. They also activate insulin signaling and inhibit digestive enzymes, regulate intestinal microbiota, improve adipose tissue metabolism, inhibit glucose absorption, and inhibit the formation of advanced glycation end products. However, insufficient data are available on the effective mechanisms necessary to manage diabetes.

Comparative effects of curcumin versus nano-curcumin on histological, immunohistochemical expression, histomorphometric, and biochemical changes to pancreatic beta cells and lipid profile of streptozocin induced diabetes in male Sprague-Dawley rats

Diabetes mellitus is a worldwide problem characterized by hyperglycemia as well as the damage of the microscopic structure of the beta cells of Langerhans pancreatic islets. In the present study, the histological, immunohistochemical, morphometric, and biochemical alterations to pancreatic beta cells in streptozocin (STZ)-induced diabetes were assessed in rats treated with curcumin (CU) (100 mg/kg/day) or nano-curcumin (nCU) (100 mg/kg/day) for 1 month. Twenty-four adult male Wistar albino rats were distributed into four groups: the nondiabetic control group, the diabetic untreated group, and two diabetic groups treated with CU or nCUR, respectively. Blood glucose, serum insulin levels, and lipid profile were measured. The pancreatic tissues were collected and processed into paraffin sections for histological and immunohistochemical examination, oxidative stress markers, and real-time PCR expression for pancreatic and duodenal homeobox 1 (PDX1). The insulin expression in beta cells was assessed using immunohistochemistry. Morphometrically, the percentage area of anti-insulin antibody reaction and the percentage area of islet cells were determined. STZ-induced deteriorating alteration in beta cells led to declines in the number of functioning beta cells and insulin immunoreactivity. In STZ-treated rats, CU and nCUR significantly reduced blood glucose concentration while increasing blood insulin level. It also caused a significant increase in the number of immunoreactive beta cells to the insulin expression and significant reduction of the immunoreactive beta cells to the caspase-3 expression. In conclusion, CU and nCUR could have a therapeutic role in the biochemical and microscopic changes in pancreatic beta cells in diabetes-induced rats through STZ administration with more bio-efficacy of nCUR.

Treatment on Nature's lap: Use of herbal products in the management of hyperglycemia

Diabetes mellitus (DM) is characterized by persistently elevated blood glucose concentration that lead to multisystem complications. There are about 400 medicinal plants cited to have a beneficial effect on DM. We must choose products wisely based on data derived from scientific studies. However, a major obstacle in the amalgamation of herbal medicine in modern medical practices is the lack of clinical data on its safety, efficacy and drug interaction. Trials of these herbal products often underreport the side effects and other crucial intervention steps deviating from the standards set by Consolidated Standards of Reporting Trials. Due to a lack of knowledge of the active compounds present in most herbal medicines, product standardization is difficult. Cost-effectiveness is another issue that needs to be kept in mind. In this mini-review, we focus on the anti-hyperglycemic effect of herbal products that are commonly used, along with the concerns stated above.

Role of Turmeric and Curcumin in Prevention and Treatment of Chronic Diseases: Lessons Learned from Clinical Trials

Turmeric (Curcuma longa) has been used for thousands of years for the prevention and treatment of various chronic diseases. Curcumin is just one of >200 ingredients in turmeric. Almost 7000 scientific papers on turmeric and almost 20,000 on curcumin have been published in PubMed. Scientific reports based on cell culture or animal studies are often not reproducible in humans. Therefore, human clinical trials are the best indicators for the prevention and treatment of a disease using a given agent/drug. Herein, we conducted an extensive literature survey on PubMed and Scopus following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The keywords "turmeric and clinical trials" and "curcumin and clinical trials" were considered for data mining. A total of 148 references were found to be relevant for the key term "turmeric and clinical trials", of which 70 were common in both PubMed and Scopus, 44 were unique to PubMed, and 34 were unique to Scopus. Similarly, for the search term "curcumin and clinical trials", 440 references were found to be relevant, of which 70 were unique to PubMed, 110 were unique to Scopus, and 260 were common to both databases. These studies show that the golden spice has enormous health and medicinal benefits for humans. This Review will extract and summarize the lessons learned about turmeric and curcumin in the prevention and treatment of chronic diseases based on clinical trials.

Curcumin Supplementation and Human Disease: A Scoping Review of Clinical Trials

Medicinal properties of turmeric (Curcuma longa L.), a plant used for centuries as an anti-inflammatory, are attributed to its polyphenolic curcuminoids, where curcumin predominates. Although "curcumin" supplements are a top-selling botanical with promising pre-clinical effects, questions remain regarding biological activity in humans. To address this, a scoping review was conducted to assess human clinical trials reporting oral curcumin effects on disease outcomes. Eight databases were searched using established guidelines, yielding 389 citations (from 9528 initial) that met inclusion criteria. Half focused on obesity-associated metabolic disorders (29%) or musculoskeletal disorders (17%), where inflammation is a key driver, and beneficial effects on clinical outcomes and/or biomarkers were reported for most citations (75%) in studies that were primarily double-blind, randomized, and placebo-controlled trials (77%, D-RCT). Citations for the next most studied disease categories (neurocognitive [11%] or gastrointestinal disorders [10%], or cancer [9%]), were far fewer in number and yielded mixed results depending on study quality and condition studied. Although additional research is needed, including systematic evaluation of diverse curcumin formulations and doses in larger D-RCT studies, the preponderance of current evidence for several highly studied diseases (e.g., metabolic syndrome, osteoarthritis), which are also clinically common, are suggestive of clinical benefits.

Therapeutic Effect of Curcumin on Metabolic Diseases: Evidence from Clinical Studies

Metabolic diseases have become a serious threat to human health worldwide. It is crucial to look for effective drugs from natural products to treat metabolic diseases. Curcumin, a natural polyphenolic compound, is mainly obtained from the rhizomes of the genus Curcuma. In recent years, clinical trials using curcumin for the treatment of metabolic diseases have been increasing. In this review, we provide a timely and comprehensive summary of the clinical progress of curcumin in the treatment of three metabolic diseases, namely type 2 diabetes mellitus (T2DM), obesity and non-alcoholic fatty liver disease (NAFLD). The therapeutic effects and underlying mechanisms of curcumin on these three diseases are presented categorically. Accumulating clinical evidence demonstrates that curcumin has good therapeutic potential and a low number of side effects for the three metabolic diseases. It can lower blood glucose and lipid levels, improve insulin resistance and reduce inflammation and oxidative stress. Overall, curcumin may be an effective drug for the treatment of T2DM, obesity and NAFLD. However, more high-quality clinical trials are still required in the future to verify its efficacy and determine its molecular mechanisms and targets.

Effect of natural polyphenols in Chinese herbal medicine on obesity and diabetes: Interactions among gut microbiota, metabolism, and immunity

With global prevalence, metabolic diseases, represented by obesity and type 2 diabetes mellitus (T2DM), have a huge burden on human health and medical expenses. It is estimated that obese population has doubled in recent 40 years, and population with diabetes will increase 1.5 times in next 25 years, which has inspired the pursuit of economical and effective prevention and treatment methods. Natural polyphenols are emerging as a class of natural bioactive compounds with potential beneficial effects on the alleviation of obesity and T2DM. In this review, we investigated the network interaction mechanism of "gut microbial disturbance, metabolic disorder, and immune imbalance" in both obesity and T2DM and systemically summarized their multiple targets in the treatment of obesity and T2DM, including enrichment of the beneficial gut microbiota (genera Bifidobacterium, Akkermansia, and Lactobacillus) and upregulation of the levels of gut microbiota-derived metabolites [short-chain fatty acids (SCFAs)] and bile acids (BAs). Moreover, we explored their effect on host glucolipid metabolism, the AMPK pathway, and immune modulation via the inhibition of pro-inflammatory immune cells (M1-like Mϕs, Th1, and Th17 cells); proliferation, recruitment, differentiation, and function; and related cytokines (TNF-α, IL-1β, IL-6, IL-17, and MCP-1). We hope to provide evidence to promote the clinical application of natural polyphenols in the management of obesity and T2DM.

The role of selected nutraceuticals in management of prediabetes and diabetes: An updated review of the literature

Dysglycemia is a disease state preceding the onset of diabetes and includes impaired fasting glycemia and impaired glucose tolerance. This review aimed to collect and analyze the literature reporting the results of clinical trials evaluating the effects of selected nutraceuticals on glycemia in humans. The results of the analyzed trials, generally, showed the positive effects of the nutraceuticals studied alone or in association with other supplements on fasting plasma glucose and post-prandial plasma glucose as primary outcomes, and their efficacy in improving insulin resistance as a secondary outcome. Some evidences, obtained from clinical trials, suggest a role for some nutraceuticals, and in particular Berberis, Banaba, Curcumin, and Guar gum, in the management of prediabetes and diabetes. However, contradictory results were found on the hypoglycemic effects of Morus, Ilex paraguariensis, Omega-3, Allium cepa, and Trigonella faenum graecum, whereby rigorous long-term clinical trials are needed to confirm these data. More studies are also needed for Eugenia jambolana, as well as for Ascophyllum nodosum and Fucus vesiculosus which glucose-lowering effects were observed when administered in combination, but not alone. Further trials are also needed for quercetin.

Curcumin and Capsaicin-Loaded Ag-Modified Mesoporous Silica Carriers: A New Alternative in Skin Treatment

Biologically active substances of natural origin offer a promising alternative in skin disease treatment in comparison to synthetic medications. The limiting factors for the efficient application of natural compounds, such as low water solubility and low bioavailability, can be easily overcome by the development of suitable delivery systems. In this study, the exchange with the template procedure was used for the preparation ofa spherical silver-modified mesoporous silica nanocarrier. The initial and drug-loaded formulations are fully characterized by different physico-chemical methods. The incipient wetness impregnation method used to load health-promoting agents, curcumin, and capsaicin in Ag-modified carriers separately or in combinationresulted in high loading efficiency (up to 33 wt.%). The interaction between drugs and carriers was studied by ATR-FTIR spectroscopy. The release experiments of both active substances from the developed formulations were studied in buffers with pH 5.5, and showed improved solubility. Radical scavenging activity and ferric-reducing antioxidant power assays were successfully used for the evaluation of the antiradical and antioxidant capacity of the curcumin or/and capsaicin loaded on mesoporous carriers. Formulations containing a mixture of curcumin and capsaicin were characterized bypotentiation of their antiproliferative effect against maligning cells, and it was confirmed that the system for simultaneous delivery of both drugs has lower IC50 values than the free substances.The antibacterial tests showed better activity of the obtained delivery systems in comparison with the pure curcumin and capsaicin. Considering the obtained results, it can be concluded that the obtained delivery systems are promising for potential dermal treatment.

An update on molecular mechanisms of curcumin effect on diabetes

Owing to its prevalent nature, diabetes mellitus has become one of the most serious endocrine illnesses affecting a patient's quality of life due to the manifestation of side effects such as cardiovascular diseases, retinopathy, neuropathy, and nephropathy. Curcumin ((1E, 6E) 21, 7-bis (4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione), a major compound of turmeric, has been used in conventional medicine because of its safe nature and cost-effectiveness to meliorate diabetes and its comorbidities. These effects have also been observed in rodent models of diabetes resulting in a reduction of glycemia and blood lipids. Both the preventive and therapeutic activities of this compound are due to its antioxidant and anti-inflammatory characteristics. Furthermore, preclinical outcomes and clinical investigation demonstrate that the use of curcumin neutralizes insulin resistance, obesity, and hyperglycemia. Despite the many benefits of curcumin, its two limiting factors, solubility and bioavailability, remain a challenge for researchers; therefore, several methods such as drug formulation, nano-drug delivery, and the use of curcumin analogs have been developed to deliver curcumin and increase its bioavailability. PRACTICAL APPLICATIONS: The rise of people with type 2 diabetes has become a major concern at the global healthcare level. The best diabetes treatments today are anti-diabetic drug administration, lifestyle-related interventions (such as healthy eating and daily physical activity), arterial pressure detection, and fat control. The polyphenol curcumin, found in turmeric, can promote health by acting on a variety of cellular signaling pathways. This review article discusses curcumin and its role in the treatment of diabetes.

Investigating Polyphenol Nanoformulations for Therapeutic Targets against Diabetes Mellitus

Diabetes mellitus (DM) is a fatal metabolic disorder, and its prevalence has escalated in recent decades to a greater extent. Since the incidence and severity of the disease are constantly increasing, plenty of therapeutic approaches are being considered as a promising solution. Many dietary polyphenols have been reported to be effective against diabetes along with its accompanying vascular consequences by targeting multiple therapeutic targets. Additionally, the biocompatibility of these polyphenols raises questions about their use as pharmacological mediators. Nevertheless, the pharmacokinetic and biopharmaceutical properties of these polyphenols limit their clinical benefit as therapeutics. Pharmaceutical industries have attempted to improve compliance and therapeutic effects. However, nanotechnological approaches to overcome the pharmacokinetic and biopharmaceutical barriers associated with polyphenols as antidiabetic medications have been shown to be effective to improve clinical compliance and efficacy. Therefore, this review highlighted a comprehensive and up-to-date assessment of polyphenol nanoformulations in the treatment of diabetes and vascular consequences.

Pharmacokinetics and Pharmacodynamics of Curcumin-Loaded Solid Lipid Nanoparticles in the Management of Streptozotocin-Induced Diabetes Mellitus: Application of Central Composite Design

Due to poor bioavailability and chemical instability, the effectiveness of curcumin is negligible in the treatment of numerous diseases. Solid lipid nanoparticles (SLNs) increase the bioavailability of lipophilic compounds and protect the drug from gastrointestinal degradation. The objective of our study is the utilization of SLNs to improve the pharmacokinetics and pharmacodynamics of curcumin in the management of diabetes mellitus. Central composite design was used to prepare curcumin-loaded SLNs (Cur-SLN). The analysis of independent variables like drug concentration, lipid concentration, and surfactant concentration was carried out using analysis of variance (ANOVA) to obtain the optimized batch (optimized Cur-SLN) having the desired values of dependent variables particle size and entrapment efficiency. In vitro release, differential scanning calorimeter (DSC), transmission electron microscopy (TEM), and Fourier Transform Infra-Red (FTIR) studies of optimized Cur-SLN were carried out and then its pharmacokinetic and pharmacodynamic studies were performed. The model was found to be significant for particle size and entrapment efficiency based on F-value and p-value. The optimized batch's predicted values were in close agreement with the actual values of particle size and entrapment efficiency. TEM results confirm mono-dispersion and spherical shape of particles in the formulation. The DSC results confirmed the changing of drug from crystalline to amorphous form. Burst release followed by the sustained release was obtained in the in vitro release studies. The pharmacokinetic study shows enhanced bioavailability of optimized Cur-SLN compared with a plain drug suspension. The optimized Cur-SLN achieved higher antidiabetic activity in streptozotocin-induced diabetes mellitus rats than the plain drug suspension. SLNs can be used as a promising technique for delivering curcumin in the management of diabetes mellitus.

Effectiveness of the piperine-supplemented Curcuma longa L. in metabolic control of patients with type 2 diabetes: a randomised double-blind placebo-controlled clinical trial

There is robust evidence of using Curcuma longa L. in reducing metabolic levels in people with diabetes. This study analysed the effectiveness of Curcuma longa L. in the metabolic control of patients with type 2 diabetes in Brazil. A randomised double-blind placebo-controlled clinical trial was conducted with 71 participants divided into a Curcuma longa L. group (500 mg/day with piperine 5 mg) and a placebo group, for 120 days. Anthropometric, clinical and biochemical variables were evaluated at baseline, 60 and 120 days after the beginning of the intervention. Paired and independent Student's t-test and chi-square test were used for statistical analysis. The curcuma group presented a significantly decreased glycaemia (p=.013), glycated haemoglobin (p=.015), HOMA index (p=.037) and triglycerides (TGs) (p=.002). The use of piperine-added Curcuma longa L. was effective in the glycaemic and TG control of patients with type 2 diabetes.

The Multifaced Actions of Curcumin in Pregnancy Outcome

Curcumin, also known as diferuloylmethane, is the main polyphenolic substance present in the rhizomes of Curcuma longa L. This plant showed many beneficial effects and has been used since ancient times for both food and pharmaceutical purposes. Due to its pleiotropic functions, curcumin consumption in the human diet has become very common thanks also to the fact that this natural compound is considered quite safe as it does not have serious side effects. Its functions as an anti-inflammatory, anti-oxidant, neuroprotective, immunomodulatory, anti-toxicant, anti-apoptotic, and anti-diabetic compound are already known and widely demonstrated. There are numerous studies concerning its effects on various human pathologies including cancer, diabetes and arthritis while the studies on curcumin during pregnancy have been performed only in animal models. Data concerning the role of curcumin as anti-inflammatory compound suggest a possible use of curcumin in managing pregnancy complications such as Preeclampsia (PE), Gestational Diabetes Mellitus (GDM), Fetal Growth Restriction (FGR), PreTerm Birth (PTB), and exposure to toxic agents and pathogens. The aim of this review is to present data to support the possible use of curcumin in clinical trials on human gestation complications.

Curcumin Inhibits Proliferation and Epithelial-Mesenchymal Transition in Lens Epithelial Cells through Multiple Pathways

Background

Posterior capsule opacification (PCO), a complication of extracapsular lens extraction surgery that causes visual impairment, is characterized by aberrant proliferation and epithelial-mesenchymal transition (EMT) of lens epithelial cells (LECs). Curcumin, exerting inhibitive effects on cell proliferation and EMT in cancer, serves as a possible antidote towards PCO.

Methods

Cellular proliferation of LECs after treatment of curcumin was measured with MTT assay and flow cytometry. The transcriptional and expressional levels of proteins related to proliferation and EMT of LECs were quantified by western blotting and real-time PCR.

Results

Curcumin was found to suppress the proliferation of LECs by inducing G₂/M arrest via possible inhibition of cell cycle-related proteins including CDK1, cyclin B1, and CDC25C. It had also inactivated proliferation pathways involving ERK1/2 and Akt pathways in LECs. On the other hand, curcumin downregulated the EMT of LECs through blocking the TGF-β/Smad pathway and interfering Notch pathway which play important roles in PCO.

Conclusions

This study shows that curcumin could suppress the proliferation and EMT in LECs, and it might be a potential therapeutic protection against visual loss induced by PCO.

Rapid measurements of curcumin from complex samples coupled with magnetic biocompatibility molecularly imprinted polymer using electrochemical detection

Curcumin widely exists in food, and rapid selective and accurate detection of curcumin have great significance in chemical industry. In this experiment, a new magnetic biocompatibility molecularly imprinted polymer was prepared with nontoxic and biocompatible Zein to adsorb curcumin selectively. The polymer has high biocompatibility, good adsorption capacity, and specific adsorption for curcumin. Combined with portable electrochemical workstations, the polymer can be used to detect curcumin rapidly and cost-effectively. Using curcumin as a template and Zein as the crosslinking agent, the polymers were synthesized on the surface of Fe₃ O₄ particles for solid phase extraction. The experimental results showed that the polymer reached large adsorption capacity (32.12 mg/g) with fast kinetics (20 min). The adsorption characteristic of the polymer followed the Langmuir isotherm and pseudo-second-order kinetic models. Hexacyanoferrate was used as electrochemical probe to generate signals, and the linear range was 5-200 µg/mL for measuring curcumin. The experimental analysis showed that the polymer was an ideal material for selective accumulation of curcumin from complex samples. This approach has been successfully applied to the determination of curcumin in food samples with electrochemical detection, indicating that this is a feasible and practical technique.

Comparative Effects of Curcumin versus Nano-Curcumin on Insulin Resistance, Serum Levels of Apelin and Lipid Profile in Type 2 Diabetic Rats

BACKGROUND AND PURPOSE

Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance and abnormalities in insulin production. Apelin is associated with insulin resistance. According to the anti-diabetic properties of curcumin, the purpose of this study was to compare the effects of curcumin and nano-curcumin intake on insulin resistance and serum levels of fasting blood sugar (FBS), Apelin, and lipid profile (cholesterol, triglyceride, LDL, HDL and VLDL) in T2DM rats.

MATERIALS AND METHODS

Forty-eight male Wistar rats were divided into six groups: Control, diabetic, diabetic treated with two doses of curcumin (100 and 200 mg/kg) and diabetic treated with two doses of nano-curcumin (100 and 200 mg/kg). Induction of T2DM was performed by intraperitoneal injection of Nicotinamide (110 mg/kg) and Streptozotocin (45 mg/kg) in the fasting state. Rats received different doses of nano-curcumin and curcumin by gavage (daily) for 28 days. At the end of the intervention period, insulin resistance and serum levels of FBS, apelin and lipid profiles were measured.

RESULTS

Insulin resistance and serum levels of FBS, Apelin, cholesterol, triglycerides, LDL, and VLDL were significantly decreased in diabetic rats treated with curcumin and nano-curcumin (p<0.05) so that nano-curcumin in reducing lipid profile is more effective than curcumin (P<0.05). Serum level of HDL in nano-curcumin groups was significantly higher than diabetic and curcumin groups (p<0.05). Also, with increasing insulin resistance, serum level of apelin increased (P<0.05).

CONCLUSION

The therapeutic effects of curcumin and nano-curcumin were effective in decreasing insulin resistance, serum levels of FBS, apelin and lipid profile. The dose of 100 mg/kg nano-curcumin was more effective in reducing lipid profile.

Antidiabetic Properties of Curcumin II: Evidence from In Vivo Studies

Type 2 diabetes mellitus (T2DM) is a growing metabolic disease characterized by insulin resistance and hyperglycemia. Current preventative and treatment approaches to insulin resistance and T2DM lack in efficacy, resulting in the need for new approaches to prevent and treat the disease. In recent years, epidemiological studies have suggested that diets rich in fruits and vegetables have beneficial health effects, including protection against insulin resistance and T2DM. Curcumin, a polyphenol found in turmeric, and curcuminoids have been reported to have antioxidant, anti-inflammatory, hepatoprotective, nephroprotective, neuroprotective, immunomodulatory and antidiabetic properties. The current review (II of II) summarizes the existing in vivo studies examining the antidiabetic effects of curcumin.

Curcumin and Type 2 Diabetes Mellitus: Prevention and Treatment

Type 2 diabetes mellitus (T2DM) is an ensemble of metabolic diseases that has reached pandemic dimensions all over the world. The multifactorial nature of the pathology makes patient management, which includes lifelong drug therapy and lifestyle modification, extremely challenging. It is well known that T2DM is a preventable disease, therefore lowering the incidence of new T2DM cases could be a key strategy to reduce the global impact of diabetes. Currently, there is growing evidence on the efficacy of the use of medicinal plants supplements for T2DM prevention and management. Among these medicinal plants, curcumin is gaining a growing interest in the scientific community. Curcumin is a bioactive molecule present in the rhizome of the Curcuma longa plant, also known as turmeric. Curcumin has different pharmacological and biological effects that have been described by both in vitro and in vivo studies, and include antioxidant, cardio-protective, anti-inflammatory, anti-microbial, nephro-protective, anti-neoplastic, hepato-protective, immunomodulatory, hypoglycaemic and anti-rheumatic effects. In animal models, curcumin extract delays diabetes development, improves β-cell functions, prevents β-cell death, and decreases insulin resistance. The present review focuses on pre-clinical and clinical trials on curcumin supplementation in T2DM and discusses the peculiar mechanisms by which curcumin might ameliorate diabetes management.

In vitro and in silico protein corona formation evaluation of curcumin and capsaicin loaded-solid lipid nanoparticles

Nanotechnology has been an important tool for the production of nanoparticles with controlled release of drugs for therapeutic applications. Here, we produced solid lipid nanoparticles (SLN) loaded with curcumin and capsaicin (NCC) following the overarching goals of green chemistry. Currently, besides evaluating the composition, and size of these, it is necessary to understand the interactions between nanoparticles and the biomolecules present in the biological medium. For this, assays were conducted in order to evaluate the potential formation of the protein 'corona', and to better understand the results obtained in vitro, we also performed an interaction study, in silico, between the NCC components and the main serum protein, albumin. In the first hour of contact between the NCC and the culture medium showed fluctuation in the diameter of the NCC. However, after 24 and 48 h of the incubation period, all NCC concentrations showed an increase in size, which can be attributed to plasma protein adsorption. Since, hard corona takes a few seconds, while the soft corona can be formed in minutes up to a few hours. On the other hand, best docking binding-poses of interaction for the formed docking complexes evaluated suggest interactions following the docking affinity like free energy FEB (Tween 80-bovine serum albumin) ≈ FEB (Span 80-bovine serum albumin) showing a pharmacodynamic pattern based in non-covalent hydrophobic interactions with the bovine serum albumin binding-site. Our in silico results clarify and reinforce our in vitro findings of corona formation, which represents the real interaction with cell membranes in vivo.

Effects of curcumin on glycemic control and lipid profile in prediabetes and type 2 diabetes mellitus: A systematic review and meta-analysis

Scope

Studies have demonstrated inconsistent effects of curcumin on glycemic outcomes and lipid parameters in patients with prediabetes and type 2 diabetes mellitus (T2DM). This study aimed to assess the effect of curcumin on glycemic control and lipid profile in prediabetes and T2DM.

Methods and results

A systematic search of randomized controlled trials (RCTs) was conducted from inception to June 2018 in electronic sources including AMED, ANZCTR, BioMed Central, CENTRAL, CINAHL, ClinicalTrials.gov, Expanded Academic Index, Google Scholar, ISRCTN, LILACS, MEDLINE, NCCIH, Science Direct, Scopus, Web of Science, and WHO ICTRP. Hand search was also performed. Of the total 486 records, four trials (N = 508) and eight trials (N = 646) were eligible for the meta-analysis of individuals with prediabetes and T2DM, respectively. Curcumin significantly reduced glycosylated hemoglobin (HbA1c) in prediabetics (MD: -0.9%, 95% CI: -1.7 to -0.1%, p = 0.03). Furthermore, T2DM subjects gained favorable reduction in both HbA1c (MD: -0.5%, 95% CI: -1.0 to -0.0%, p = 0.04) and fasting plasma glucose (MD: -11.7 mg/dL, 95% CI: -22.1 to -1.3 mg/dL, p = 0.03). Tendency of lipid profile improvement was also observed.

Conclusion

Our findings may encourage curcumin supplementation based on its meaningful effect on glycemic control and positive trend on lipid outcomes in prediabetes and T2DM.

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.

Curcumin modulates the apolipoprotein B mRNA editing by coordinating the expression of cytidine deamination to uridine editosome components in primary mouse hepatocytes

Curcumin, an active ingredient of Curcuma longa L., can reduce the concentration of low-density lipoproteins in plasma, in different ways. We had first reported that curcumin exhibits hypocholesterolemic properties by improving the apolipoprotein B (apoB) mRNA editing in primary rat hepatocytes. However, the role of curcumin in the regulation of apoB mRNA editing is not clear. Thus, we investigated the effect of curcumin on the expression of multiple editing components of apoB mRNA cytidine deamination to uridine (C-to-U) editosome. Our results demonstrated that treatment with 50 µM curcumin markedly increased the amount of edited apoB mRNA in primary mouse hepatocytes from 5.13%–8.05% to 27.63%–35.61%, and significantly elevated the levels of the core components apoB editing catalytic polypeptide-1 (APOBEC-1), apobec-1 complementation factor (ACF), and RNA-binding-motif-protein-47 (RBM47), as well as suppressed the level of the inhibitory component glycine-arginine-tyrosine-rich RNA binding protein. Moreover, the increased apoB RNA editing by 50 µM curcumin was significantly reduced by siRNA-mediated APOBEC-1, ACF, and RBM47 knockdown. These findings suggest that curcumin modulates apoB mRNA editing by coordinating the multiple editing components of the editosome in primary hepatocytes. Our data provided evidence for curcumin to be used therapeutically to prevent atherosclerosis.

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.

Small molecules as inhibitors of PCSK9: Current status and future challenges

Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays an important role in regulating lipoprotein metabolism by binding to low-density lipoprotein receptors (LDLRs), leading to their degradation. LDL cholesterol (LDL-C) lowering drugs that operate through the inhibition of PCSK9 are being pursued for the management of hypercholesterolemia and reducing its associated atherosclerotic cardiovascular disease (CVD) risk. Two PCSK9-blocking monoclonal antibodies (mAbs), alirocumab and evolocumab, were approved in 2015. However, the high costs of PCSK9 antibody drugs impede their prior authorization practices and reduce their long-term adherence. Given the potential of small-molecule drugs, the development of small-molecule PCSK9 inhibitors has attracted considerable attention. This article provides an overview of the recent development of small-molecule PCSK9 inhibitors disclosed in the literature and patent applications, and different approaches that have been pursued to modulate the functional activity of PCSK9 using small molecules are described. Challenges and potential strategies in developing small-molecule PCSK9 inhibitors are also discussed.

Activation of Nrf2 signaling by natural products-can it alleviate diabetes?

Type 2 diabetes mellitus (DM) has reached pandemic proportions and effective prevention strategies are wanted. Its onset is accompanied by cellular distress, the nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor boosting cytoprotective responses, and many phytochemicals activate Nrf2 signaling. Thus, Nrf2 activation by natural products could presumably alleviate DM. We summarize function, regulation and exogenous activation of Nrf2, as well as diabetes-linked and Nrf2-susceptible forms of cellular stress. The reported amelioration of insulin resistance, β-cell dysfunction and diabetic complications by activated Nrf2 as well as the status quo of Nrf2 in precision medicine for DM are reviewed.

Bioactivity, Health Benefits, and Related Molecular Mechanisms of Curcumin: Current Progress, Challenges, and Perspectives

Curcumin is a principal curcuminoid of turmeric (Curcuma longa), which is commonly used as a spice in cooking and a yellow pigment in the food processing industry. Recent studies have demonstrated that curcumin has a variety of biological activities and pharmacological performances, providing protection and promotion of human health. In addition to presenting an overview of the gut metabolism of curcumin, this paper reviews the current research progress on its versatile bioactivity, such as antioxidant, anti-inflammatory, and immune-regulatory activities, and also intensively discusses its health benefits, including the protective or preventive effects on cancers and diabetes, as well as the liver, nervous system, and cardiovascular systems, highlighting the potential molecular mechanisms. Besides, the beneficial effects of curcumin on human are further stated based on clinical trials. Considering that there is still a debate on the beneficial effects of curcumin, we also discuss related challenges and prospects. Overall, curcumin is a promising ingredient of novel functional foods, with protective efficacy in preventing certain diseases. We hope this comprehensive and updated review will be helpful for promoting human-based studies to facilitate its use in human health and diseases in the future.

Spice-Derived Bioactive Ingredients: Potential Agents or Food Adjuvant in the Management of Diabetes Mellitus

Spices possess tremendous therapeutic potential including hypoglycemic action, attributed to their bioactive ingredients. However, there is no study that critically reviewed the hypoglycemic potency, safety and the bioavailability of the spice-derived bioactive ingredients (SDBI). Therefore, the aim of the study was to comprehensively review all published studies regarding the hypoglycemic action of SDBI with the purpose to assess whether the ingredients are potential hypoglycemic agents or adjuvant. Factors considered were concentration/dosages used, the extent of blood glucose reduction, the IC50 values, and the safety concern of the SDBI. From the results, cinnamaldehyde, curcumin, diosgenin, thymoquinone (TQ), and trigonelline were showed the most promising effects and hold future potential as hypoglycemic agents. Conclusively, future studies should focus on improving the tissue and cellular bioavailability of the promising SDBI to achieve greater potency. Additionally, clinical trials and toxicity studies are with these SDBI are warranted.