Cinnamon extract attenuates TNF-alpha-induced intestinal lipoprotein ApoB48 overproduction by regulating inflammatory, insulin, and lipoprotein pathways in enterocytes

Allyl isothiocyanate, a TRPA1 agonist, protects against olanzapine-induced hypothalamic and hepatic metabolic aberrations in female mice

Olanzapine, a widely prescribed atypical antipsychotic, poses a great risk to the patient's health by fabricating a plethora of severe metabolic and cardiovascular adverse effects eventually reducing life expectancy and patient compliance. Its heterogenous receptor binding profile has made it difficult to point out a specific cause or treatment for the related side effects. Growing body of evidence suggest that transient receptor potential (TRP) channel subfamily Ankyrin 1 (TRPA1) has pivotal role in pathogenesis of type 2 diabetes and obesity. With this background, we aimed to investigate the role of pharmacological manipulations of TRPA1 channels in antipsychotic (olanzapine)-induced metabolic alterations in female mice using allyl isothiocyanate (AITC) and HC-030031 (TRPA1 agonist and antagonist, respectively). It was found that after 6 weeks of treatment, AITC prevented olanzapine-induced alterations in body weight and adiposity; serum, and liver inflammatory markers; glucose and lipid metabolism; and hypothalamic appetite regulation, nutrient sensing, inflammatory and TRPA1 channel signaling regulating genes. Furthermore, several of these effects were absent in the presence of HC-030031 (TRPA1 antagonist) indicating protective role of TRPA1 agonism in attenuating olanzapine-induced metabolic alterations. Supplementary in-depth studies are required to study TRPA1 channel effect on other aspects of olanzapine-induced metabolic alterations.

Control of the microsporidian parasite Nosema ceranae in honey bees (Apis mellifera) using nutraceutical and immuno-stimulatory compounds

Nosema ceranae is a microsporidian parasite that causes nosemosis in the honey bee (Apis mellifera). As alternatives to the antibiotic fumagillin, ten nutraceuticals (oregano oil, thymol, carvacrol, trans-cinnmaldehyde, tetrahydrocurcumin, sulforaphane, naringenin, embelin, allyl sulfide, hydroxytyrosol) and two immuno-stimulatory compounds (chitosan, poly I:C) were examined for controlling N. ceranae infections. Caged bees were inoculated with N. ceranae spores, and treatments were administered in sugar syrup. Only two compounds did not significantly reduce N. ceranae spore counts compared to the infected positive control, but the most effective were sulforaphane from cruciferous vegetables, carvacrol from oregano oil, and naringenin from citrus fruit. When tested at several concentrations, the highest sulforaphane concentration reduced spore counts by 100%, but also caused 100% bee mortality. For carvacrol, the maximum reduction in spore counts was 57% with an intermediate concentration and the maximum bee mortality was 23% with the highest concentration. For naringenin, the maximum reduction in spore counts was 64% with the highest concentration, and the maximum bee mortality was only 15% with an intermediate concentration. In the longevity experiment, naringenin-fed bees lived as long as Nosema-free control bees, both of which lived significantly longer than infected positive control bees. While its antimicrobial properties may be promising, reducing sulforaphane toxicity to bees is necessary before it can be considered as a candidate for controlling N. ceranae. Although further work on formulation is needed with naringenin, its effect on extending longevity in infected bees may give it an additional value as a potential additive for bee feed in honey bee colonies.

Modulating and opposite actions of two aqueous extracts prepared from Cinnamomum cassia L. bark and Quercus ilex L. on the gastrointestinal tract in rats

Cinnamon bark and evergreen oak acorns, natural sources of functional ingredients, are effective for those suffering from diarrhea, constipation and irritable bowel syndrome. This study aimed to evaluate the dissimilar phytochemical composition and the opposite potential actions of Cinnamomum cassia bark (ACCE) and Quercus ilex aqueous extracts (GIAE) on gastrointestinal (GI)-physiological activities and disruptions. An HPLC-PDA/ESI-MS assay was used to identify the distinctive qualitative and quantitative profiles of phenolic compounds. The GI-physiological action of both extracts on gastric emptying (GE) and gastrointestinal transit time (GIT) were evaluated using the phenol-red colorimetric method and a test meal containing charcoal/gum arabic in water. Loperamide (LOP)-induced colonic constipation and delayed emptying of the stomach were used to explore the reverse effects of ACCE/GIAE on GI disorders. HPLC-PDA/ESI-MS showed that the main phenolic compounds detected in ACCE are trans-cinnamic acid, quinic acid, protocatechuic acid and rosmarinic acid, while gallic acid, quinic acid and protocatechuic acid are the major chemical constituents found in GIAE. GIAE at two doses (150 and 300 mg kg⁻¹) exerted a reduction of GE (66.40% and 60.87%, respectively) compared to a control group (70.25%). However, ACCE at the same concentrations induced contradictory actions on GE/GIT in comparison to GIAE and antagonistic synthetic pharmacological drugs in rats. The protective effect of CCAE against constipation induced by LOP in rats was accompanied by a strong antioxidant property related to moderation of intracellular-mediator disorders. An absence of toxic actions was revealed in the case of the hematological profile and biochemical parameters. Hence, in-depth investigations of these nutrients of both extracts may help future researchers to derive the underlying mechanisms and potential molecular targets for the development of physiologically functional foods and future therapies.

Cinnamon bark and evergreen oak acorns, natural sources of functional ingredients, are effective for those suffering from diarrhea, constipation and irritable bowel syndrome.

Cinnamon Polyphenol Extract and Insulin Regulate Diacylglycerol Acyltransferase Gene Expression in Mouse Adipocytes and Macrophages

Cinnamon polyphenol extract (CPE) improves people with insulin resistance. The objective was to investigate CPE and insulin on diacylglycerol acyltransferase (DGAT) gene expression important for lipid biosynthesis and compared it to anti-inflammatory tristetraprolin/zinc finger protein 36 (TTP/ZFP36) gene expression known to be regulated by both agents. Mouse 3T3-L1 adipocytes and RAW264.7 macrophages were treated with insulin and CPE followed by qPCR evaluation of DGAT and TTP mRNA levels. Insulin decreased DGAT1 and DGAT2 mRNA levels in adipocytes but had no effect on DGAT1 and increased DGAT2 mRNA levels 3-fold in macrophages. Insulin increased TTP mRNA levels 3-fold in adipocytes but had no effect in macrophages. CPE effect on DGAT1 gene expression was minimal but increased DGAT2 mRNA levels 2-4 fold in adipocytes and macrophages. CPE increased TTP mRNA levels 2-7 fold in adipocytes and macrophages. We conclude that CPE and insulin exhibited overlapping and independent effects on DGAT and TTP gene expression and suggest that CPE and insulin have profound effects on fat biosynthesis and inflammatory responses.

Reduced obesity, diabetes, and steatosis upon cinnamon and grape pomace are associated with changes in gut microbiota and markers of gut barrier

Increasing evidence suggests that polyphenols have a significant potential in the prevention and treatment of risk factors associated with metabolic syndrome. The objective of this study was to assess the metabolic outcomes of two polyphenol-containing extracts from cinnamon bark (CBE) and grape pomace (GPE) on C57BL/6J mice fed a high-fat diet (HFD) for 8 wk. Both CBE and GPE were able to decrease fat mass gain and adipose tissue inflammation in mice fed a HFD without reducing food intake. This was associated with reduced liver steatosis and lower plasma nonesterified fatty acid levels. We also observed a beneficial effect on glucose homeostasis, as evidenced by an improved glucose tolerance and a lower insulin resistance index. These ameliorations of the overall metabolic profile were associated with a significant impact on the microbial composition, which was more profound for the GPE than for the CBE. At the genus level, Peptococcus were decreased in the CBE group. In the GPE-treated group, several key genera that have been previously found to be linked with HFD, metabolic effects, and gut barrier integrity were affected: we observed a decrease of Desulfovibrio, Lactococcus, whereas Allobaculum and Roseburia were increased. In addition, the expression of several antimicrobial peptides and tight junction proteins was increased in response to both CBE and GPE supplementation, indicating an improvement of the gut barrier function. Collectively, these data suggest that CBE and GPE can ameliorate the overall metabolic profile of mice on a high-fat diet, partly by acting on the gut microbiota.

Cinnamon Polyphenol Extract Inhibits Hyperlipidemia and Inflammation by Modulation of Transcription Factors in High-Fat Diet-Fed Rats

We evaluated the effects of cinnamon polyphenol extract on hepatic transcription factors expressions including SREBP-1c and LXR-α in rats fed high fat diet (HFD). Twenty-eight Wistar rats were allocated into four groups: (i) normal control: animals fed with normal chow; (ii) cinnamon: animals supplemented with cinnamon polyphenol; (iii) HFD: animals fed a high-fat diet; and (iv) HFD + cinnamon: animals fed a high-fat diet and treated with cinnamon polyphenol. Obesity was linked to hyperglycemia, hyperlipidemia, and oxidative stress as imitated by elevated serum glucose, lipid profile, and serum and liver malondialdehyde (MDA) concentrations. Cinnamon polyphenol decreased body weight, visceral fat, liver weight and serum glucose and insulin concentrations, liver antioxidant enzymes, and lipid profile (P < 0.05) and reduced serum and liver MDA concentration compared to HFD rats (P < 0.05). Cinnamon polyphenol also suppressed the hepatic SREBP-1c, LXR-α, ACLY, FAS, and NF-κB p65 expressions and enhanced the PPAR-α, IRS-1, Nrf2, and HO-1 expressions in the HFD rat livers (P < 0.05). In conclusion, cinnamon polyphenol reduces the hyperlipidemia, inflammation, and oxidative stress through activating transcription factors and antioxidative defense signaling pathway in HFD rat liver.

Potential therapeutic value of TRPV1 and TRPA1 in diabetes mellitus and obesity

Diabetes mellitus and obesity, which is a major risk factor in the development of type 2 diabetes mellitus, have reached epidemic proportions worldwide including the USA. The current statistics and forecasts, both short- and long-term, are alarming and predict severe problems in the near future. Therefore, there is a race for developing new compounds, discovering new receptors, or finding alternative solutions to prevent and/or treat the symptoms and complications related to obesity and diabetes mellitus. It is well demonstrated that members of the transient receptor potential (TRP) superfamily play a crucial role in a variety of biological functions both in health and disease. In the recent years, transient receptor potential vanilloid type 1 (TRPV1) and transient receptor potential ankyrin 1 (TRPA1) were shown to have beneficial effects on whole body metabolism including glucose homeostasis. TRPV1 and TRPA1 have been associated with control of weight, pancreatic function, hormone secretion, thermogenesis, and neuronal function, which suggest a potential therapeutic value of these channels. This review summarizes recent findings regarding TRPV1 and TRPA1 in association with whole body metabolism with emphasis on obese and diabetic conditions.

A Dietary Supplement Containing Cinnamon, Chromium and Carnosine Decreases Fasting Plasma Glucose and Increases Lean Mass in Overweight or Obese Pre-Diabetic Subjects: A Randomized, Placebo-Controlled Trial

BACKGROUND

Preventing or slowing the progression of prediabetes to diabetes is a major therapeutic issue.

OBJECTIVES

Our aim was to evaluate the effects of 4-month treatment with a dietary supplement containing cinnamon, chromium and carnosine in moderately obese or overweight pre-diabetic subjects, the primary outcome being change in fasting plasma glucose (FPG) level. Other parameters of plasma glucose homeostasis, lipid profile, adiposity and inflammatory markers were also assessed.

METHODS

In a randomized, double-blind, placebo-controlled study, 62 subjects with a FPG level ranging from 5.55 to 7 mmol/L and a body mass index ≥ 25 kg/m(2), unwilling to change their dietary and physical activity habits, were allocated to receive a 4-month treatment with either 1.2 g/day of the dietary supplement or placebo. Patients were followed up until 6 months post-randomization.

RESULTS

Four-month treatment with the dietary supplement decreased FPG compared to placebo (-0.24 ± 0.50 vs +0.12 ± 0.59 mmol/L, respectively, p = 0.02), without detectable significant changes in HbA1c. Insulin sensitivity markers, plasma insulin, plasma lipids and inflammatory markers did not differ between the treatment groups. Although there were no significant differences in changes in body weight and energy or macronutrient intakes between the two groups, fat-free mass (%) increased with the dietary supplement compared to placebo (p = 0.02). Subjects with a higher FPG level and a milder inflammatory state at baseline benefited most from the dietary supplement.

CONCLUSIONS

Four-month treatment with a dietary supplement containing cinnamon, chromium and carnosine decreased FPG and increased fat-free mass in overweight or obese pre-diabetic subjects. These beneficial effects might open up new avenues in the prevention of diabetes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01530685.

Cinnamon extract lowers glucose, insulin and cholesterol in people with elevated serum glucose

Cinnamon (肉桂 ròu guì) has in vitro insulin potentiating activity, and proanthocyanidins from cinnamon prevent in vitro formation of advanced glycation end products. Some human studies were equivocal, but several have shown beneficial effects of cinnamon supplementation on circulating glucose, lipids, and/or insulin. This placebo-controlled double-blind trial tested the effects of a dried water extract of cinnamon (Cinnamomum cassia) on circulating glucose, lipids, insulin, and insulin resistance. Men and women from Beijing and Dalian, China, were invited to participate if they had fasting serum glucose >6.1 mmol/L or 2-h glucose >7.8 mmol/L. Participants, (173 were enrolled and 137 completed the study) were randomly assigned to receive either a spray-dried, water extract of cinnamon (CinSulin^®), 250 mg/capsule, or a placebo, twice a day for two months. Mean ± SEM age of participants was 61.3 ± 0.8 years, BMI was 25.3 ± 0.3 and M/F ratio was 65/72. After 2 mo, fasting glucose decreased (p < 0.001) in the cinnamon extract-supplemented group (8.85 ± 0.36 to 8.19 ± 0.29 mmol/L) compared with the placebo group (8.57 ± 0.32 to 8.44 ± 0.34 mmol/L, p = 0.45). Glucose 2 h after a 75 g carbohydrate load, fasting insulin, and HOMA-IR also decreased with cinnamon extract compared with placebo. Total and LDL-cholesterol decreased with cinnamon extract and HDL-cholesterol decreased in both the cinnamon-extract and placebo groups. In conclusion, supplementation with 500 mg of water-extract of cinnamon for two months reduced fasting insulin, glucose, total cholesterol, and LDL cholesterol and enhanced insulin sensitivity of subjects with elevated blood glucose.

Cinnamon polyphenols attenuate the hydrogen peroxide-induced down regulation of S100β secretion by regulating sirtuin 1 in C6 rat glioma cells

AIMS

It is well established that the brain is particularly susceptible to oxidative damage due to its high consumption of oxygen. The objective of this study was to investigate the protective effects of a water soluble polyphenol-rich extract of cinnamon and the possible mechanisms, under conditions of oxidative stress-induced by hydrogen peroxide, in rat C6 glioma cells.

MAIN METHODS

After 24h of H2O2 incubation, the secretion and intracellular expression of S100β were determined by immunoprecitation/immunoblotting and immunofluorescence imaging.

KEY FINDINGS

Cinnamon polyphenols (CP) counteracted the oxidative effects of H2O2 on S100β secretion and expression. CP also enhanced the impaired protein levels of sirtuins 1, 2, and 3, which are deacetylases important in cell survival. H2O2 also induced the overexpression of the proinflammatory factors, TNF-α, phospho-NF-κB p65, as well as of Bcl-xl, Bax and Caspase-3, which are all the members of the Bcl-2 family. CP not only suppressed the expression of these proteins but also attenuated the phosphorylation induced by H2O2. CP also upregulated the decreased Bcl-2 protein levels in H2O2 treated C6 cells. The effects of CP on H2O2-induced downregulation of S100β secretion were blocked by SIRT1 siRNA demonstrating that SIRT1 plays a regulatory role in CP-mediated prevention by H2O2.

SIGNIFICANCE

These data demonstrate that Cinnamon polyphenols may exert neuroprotective effects in glial cells by the regulation of Bcl-2 family members and enhancing SIRT1 expression during oxidative stress.

Effect of a high-fat--high-fructose diet, stress and cinnamon on central expression of genes related to immune system, hypothalamic-pituitary-adrenocortical axis function and cerebral plasticity in rats

The intake of a high-fat/high-fructose (HF/HFr) diet is described to be deleterious to cognitive performances, possibly via the induction of inflammatory factors. An excess of glucocorticoids is also known to exert negative effects on cerebral plasticity. In the present study, we assessed the effects of an unbalanced diet on circulating and central markers of inflammation and glucocorticoid activity, as well as their reversal by dietary cinnamon (CN) supplementation. A group of male Wistar rats were subjected to an immune challenge with acute lipopolysaccharide under a HF/HFr or a standard diet. Another group of Wistar rats were fed either a HF/HFr or a control diet for 12 weeks, with or without CN supplementation, and with or without restraint stress (Str) application before being killed. We evaluated the effects of such regimens on inflammation parameters in the periphery and brain and on the expression of actors of brain plasticity. To assess hypothalamic-pituitary-adrenocortical axis activity, we measured the plasma concentrations of corticosterone and the expression of central corticotrophin-releasing hormone, mineralocorticoid receptor, glucocorticoid receptor and 11β-hydroxysteroid dehydrogenase. We found that the HF/HFr diet induced the expression of cytokines in the brain, but only after an immune challenge. Furthermore, we observed the negative effects of Str on the plasma concentrations of corticosterone and neuroplasticity markers in rats fed the control diet but not in those fed the HF/HFr diet. Additionally, we found that CN supplementation exerted beneficial effects under the control diet, but that its effects were blunted or even reversed under the HF/HFr diet. CN supplementation could be beneficial under a standard diet. [corrected].

Cinnamon polyphenols regulate S100β, sirtuins, and neuroactive proteins in rat C6 glioma cells

OBJECTIVE

Increasing evidence suggests that cinnamon has many health benefits when used in herbal medicine and as a dietary ingredient. The aim of this study was to investigate the effects of an aqueous extract of cinnamon, high in type A polyphenols, on molecular targets in rat C6 glioma cells that underlie their protective effects.

METHODS

C6 rat glioma cells were seeded in 35-mm culture dishes or six-well plates, then were incubated with cinnamon polyphenols at doses of 10 and 20 μg/mL for 24 h. The targeting protein expression, secretion, and phosphorylation were evaluated by immunoprecitation/immunoblotting and immunofluorescence imaging.

RESULTS

Cinnamon polyphenols significantly enhanced secretion of S100β, a Ca(2+)-binding protein, and increased intracellular S100β expression after 24 h of incubation, in rat C6 glioma cells. Cinnamon polyphenols also enhanced protein levels of sirtuin 1, 2, and 3, deacetylases important in cell survival, and the tumor suppressor protein, p53, and inhibited the inflammatory factors, tumor necrosis factor alpha, and phospho-p65, a subunit of nuclear factor-κβ. Cinnamon polyphenols also up-regulated levels of phospho-p38, extracellular signal-regulated protein and mitogen-activated protein and kinase-activated protein kinases that may be important for prosurvival functions.

CONCLUSION

Our results indicate that the effects of cinnamon polyphenols on upregulating prosurvival proteins, activating mitogen-activated protein kinase pathways, and decreasing proinflammatory cytokines may contribute to their neuroprotective effects.

Nutritionally mediated oxidative stress and inflammation

There are many sources of nutritionally mediated oxidative stress that trigger inflammatory cascades along short and long time frames. These events are primarily mediated via NF κ B. On the short-term scale postprandial inflammation is characterized by an increase in circulating levels of IL-6 and TNF- α and is mirrored on the long-term by proinflammatory gene expression changes in the adipocytes and peripheral blood mononuclear cells (PBMCs) of obese individuals. Specifically the upregulation of CCL2/MCP-1, CCL3/MIP-1 α , CCL4/MIP-1 β , CXCL2/MIP-2 α , and CXCL3/MIP-2 β is noted because these changes have been observed in both adipocytes and PBMC of obese humans. In comparing numerous human intervention studies it is clear that pro-inflammatory and anti-inflammatory consumption choices mediate gene expression in humans adipocytes and peripheral blood mononuclear cells. Arachidonic acid and saturated fatty acids (SFAs) both demonstrate an ability to increase pro-inflammatory IL-8 along with numerous other inflammatory factors including IL-6, TNF α , IL-1 β , and CXCL1 for arachidonic acid and IGB2 and CTSS for SFA. Antioxidant rich foods including olive oil, fruits, and vegetables all demonstrate an ability to lower levels of IL-6 in PBMCs. Thus, dietary choices play a complex role in the mediation of unavoidable oxidative stress and can serve to exacerbate or dampen the level of inflammation.

Water extract of Cinnamomum cassia Blume inhibited human respiratory syncytial virus by preventing viral attachment, internalization, and syncytium formation

ETHNOPHARMACOLOGICAL RELEVANCE

Cinnamomum cassia Blume is a popular traditional Chinese herbal medicine that has been used to manage respiratory tract disease, including common cold and chronic bronchitis for thousand years. Human respiratory syncytial virus (HRSV) is one of the leading causes of severe lower respiratory tract illness worldwide. No effective therapeutic modality against HRSV infection has been proved. It is unknown whether Cinnamomum cassia is effective against HRSV.

AIM OF THE STUDY

This study tested the hypothesis that Cinnamomum cassia can effectively decrease HRSV-induced plaque formation and syncytium formation in respiratory mucosal cell lines.

MATERIALS AND METHODS

Antiviral activity of the hot water extract of Cinnamomum cassia against HRSV was tested by plaque reduction assay in both human upper (HEp-2) and low (A549) respiratory tract cell lines. Its ability to inhibit the synthesis of viral fusion (F) protein was examined by Western blot assay.

RESULTS

Cinnamomum cassia dose-dependently inhibited HRSV-induced plaque formation in both HEp-2 and A549 cell lines (p<0.0001). Cinnamomum cassia was more effective when given before viral infection (p<0.0001) mainly by inhibition of viral attachment (p<0.0001) and internalization (p<0.0001). Cinnamomum cassia could inhibit F protein production and syncytium formation to interfere with HRSV spreading.

CONCLUSIONS

Cinnamomum cassia prevented airway epithelia from HRSV infection through inhibiting viral attachment, internalization and syncytium formation. Cinnamomum cassia could be a candidate to develop therapeutic modalities to manage HRSV infection in the future.

Ameliorative Effects of a Polyphenolic Fraction of Cinnamomum zeylanicum L. Bark in Animal Models of Inflammation and Arthritis

Cinnamon bark (Cinnamomum zeylanicum Syn C. verum, family: Lauraceae) is one of the oldest traditional medicines for inflammatory- and pain-related disorders. The objective of the present study was to evaluate the efficacy of the polyphenol fraction from Cinnamomum zeylanicum bark (CPP) in animal models of inflammation and rheumatoid arthritis. Dose-response studies of CPP (50, 100, and 200 mg/kg) used in a separate set of in vivo experiments were conducted in acute (carrageenan-induced rat paw edema), subacute (cotton pellet-induced granuloma), and sub-chronic (AIA, adjuvant-induced established polyarthrtis) models of inflammation in rats and the acetic acid-induced writhing model of pain in mice. Effects of CPP on cytokine (IL-2, IL-4, and IFNγ) release from Concanavalin (ConA)-stimulated lymphocytes were also evaluated in vitro. CPP showed a strong and dose-dependent reduction in paw volume, weight loss reversal effects against carrageenan-induced paw edema, and cotton pellet-induced granuloma models in rats. CPP (200 mg/kg p.o. for 10 days) showed a significant reduction in elevated serum TNF-α concentration without causing gastric ulcerogenicity in the AIA model in rats. CPP also demonstrated mild analgesic effects during acute treatment as evidenced by the reduction in the writhing and paw withdrawal threshold of the inflamed rat paw during the acetic acid-induced writhing model and Randall-Selitto test. CPP was found to inhibit cytokine (IL-2, IL-4, and IFNγ) release from ConA-stimulated lymphocytes in vitro. In conclusion, CPP demonstrated prominent action in animal models of inflammation and arthritis and therefore can be considered as a potential anti-rheumatic agent with disease-modifying action.

Controversies surrounding the clinical potential of cinnamon for the management of diabetes

Obesity levels have increased significantly in the past five decades and are predicted to continue rising, resulting in important health implications. In particular, this has translated to an increase in the occurrence of type II diabetes mellitus (T2D). To alleviate associated problems, certain nutraceuticals have been considered as potential adjuncts or alternatives to conventional prescription drugs. Cinnamon, a commonly consumed spice originating from South East Asia, is currently being investigated as a potential preventative supplement and treatment for insulin resistance, metabolic syndrome and T2D. Extensive in vitro evidence has shown that cinnamon may improve insulin resistance by preventing and reversing impairments in insulin signalling in skeletal muscle. In adipose tissue, it has been shown that cinnamon increases the expression of peroxisome proliferator-activated receptors including, PPARγ. This is comparable to the action of commonly used thiazolinediones, which are PPAR agonists. Studies have also shown that cinnamon has potent anti-inflammatory properties. However, numerous human clinical trials with cinnamon have been conducted with varying findings. While some studies have showed no beneficial effect, others have indicated improvements in cholesterol levels, systolic blood pressure, insulin sensitivity and postprandial glucose levels with cinnamon. However, the only measurement consistently improved by cinnamon consumption is fasting glucose levels. While it is still premature to suggest the use of cinnamon supplementation based on the evidence, further investigation into mechanisms of action is warranted. Apart from further characterization of genetic and epigenetic changes in model systems, systematic large-scale clinical trials are required. In this study, we discuss the mechanisms of action of cinnamon in the context of T2D and we highlight some of the associated controversies.

Functional food and diabetes: a natural way in diabetes prevention?

Diabetes shows a wide range of variation in prevalence around the world and it is expected to affect 300 million by the year 2025. In a prevention framework where banning policies and educational strategies lead the interventions, functional foods (FFs) with their specific health effects could, in the future, indicate a new mode of thinking about the relationships between food and health in everyday life. Functional ingredients, such as stevioside, cinnamon, bitter melon, garlic and onion, ginseng, Gymnema sylvestre and fenugreek, have been addressed for their specific actions towards different reactions involved in diabetes development. New strategies involving the use of FF should be validated through large-scale population trials, considering validated surrogate end points to evaluate the effect of FF in prevention of chronic diseases such as type 2 diabetes mellitus.

Bioactivity of cinnamon with special emphasis on diabetes mellitus: a review

Cinnamon is the oldest spice and has been used by several cultural practices for centuries. In addition to its culinary uses, cinnamon possesses a rising popularity due to many stated health benefits. Out of the large number of cinnamon species available, Cinnamomum aromaticum (Cassia) and Cinnamomum zeylanicum have been subjected to extensive research. Available in vitro and in vivo evidence indicates that cinnamon may have multiple health benefits, mainly in relation to hypoglycaemic activity. Furthermore, the therapeutic potential of cinnamon is stated also to be brought about by its anti-microbial, anti-fungal, antiviral, antioxidant, anti-tumour, blood pressure-lowering, cholesterol and lipid-lowering and gastro-protective properties. This article provides a summary of the scientific literature available on both C. aromaticum and C. zeylanicum. All studies reported here have used cinnamon bark and its products. Although almost all the animal models have indicated a pronounced anti-diabetic activity of both cinnamon species, conflicting results were observed with regard to the few clinical trials available. Therefore, the necessity of evaluating the effects of cinnamon for its therapeutic potential through well-defined and adequately powered randomized controlled clinical trials is emphasized, before recommendations are made for the use of cinnamon as an effective treatment for humans.

Bamboo extract reduces interleukin 6 (IL-6) overproduction under lipotoxic conditions through inhibiting the activation of NF-κB and AP-1 pathways

Interleukin 6 (IL-6) is an inflammatory cytokine overexpressed in obese individuals that contributes to the development of diseases such as insulin resistance, type 2 diabetes, and cardiovascular disease. This study investigated the inhibitory effect of an extract from the bamboo Phyllostachys edulis (BEX) on lipotoxicity-induced over-production of IL-6 in metabolic cell lines. Palmitic acid (PA, 0.4mM) was used to induce lipotoxicity in murine C2C12, 3T3-L1, and Hepa6 cells. Both intra- and extra-cellular protein concentrations of IL-6 were measured in the three cell lines after PA treatment with or without the presence of BEX using cytometric bead assays. IL-6 mRNA levels were quantified using real-time PCR, and nuclear concentrations of c-fos, p50 and p65 proteins were measured using DNA-binding ELISA in 3T3-L1 cells. Lipotoxicity increased IL-6 protein concentration in both cytosol and media collected from myoblast and myotube C2C12, as well as preadipose and adipose 3T3-L1, and the presence of BEX (0.5%, v/v) effectively inhibited this overproduction. IL-6 protein expression in hepatic Hepa6 cells was less affected by lipotoxicity. BEX significantly ameliorated PA-induced upregulation of IL-6 mRNA, which correlated with a reduction in nuclear translocation of p50, p65, and c-fos proteins with the presence of BEX, indicating inhibition of NF-κB and AP-1 activation. In summary, BEX inhibits lipotoxicity-induced IL-6 overproduction in muscle and adipose cell lines through the NF-κB and AP-1 pathways, implicating a potential application of this natural product as a cost-effective anti-inflammation nutraceutical.

Cinnamon polyphenol extract regulates tristetraprolin and related gene expression in mouse adipocytes

Cinnamon (Cinnamomum verum) has been widely used in spices, flavoring agents, and preservatives. Cinnamon polyphenol extract (CPE) may be important in the alleviation of chronic diseases, but the molecular evidence is not substantial. Tristetraprolin (TTP) family proteins have anti-inflammatory effects through the destabilization of pro-inflammatory mRNAs. TTP expression is reduced in fats of obese people with metabolic syndrome and brains of suicide victims. This study used quantitative real-time PCR to explore the effects of CPE on the regulation of TTP, VEGF, and related gene expression in mouse 3T3-L1 adipocytes. CPE (100 μg/mL) increased TTP mRNA levels by up to 10-fold, and this stimulation was sustained over 16 h. The levels of VEGF mRNA, a putative target of TTP, were decreased 40-50% by CPE. It also affected the expression of other genes coding for ZFP36L1 and ZFP36L3 (TTP homologues), GM-CSF, COX2, IL6, APP, G-CSF, and PAI1. This study demonstrated that CPE rapidly induces TTP mRNA and reduces VEGF mRNA and affects the expression of a number of other genes in the cultured adipocytes.

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

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

Cinnamon: potential role in the prevention of insulin resistance, metabolic syndrome, and type 2 diabetes

Metabolic syndrome is associated with insulin resistance, elevated glucose and lipids, inflammation, decreased antioxidant activity, increased weight gain, and increased glycation of proteins. Cinnamon has been shown to improve all of these variables in in vitro, animal, and/or human studies. In addition, cinnamon has been shown to alleviate factors associated with Alzheimer's disease by blocking and reversing tau formation in vitro and in ischemic stroke by blocking cell swelling. In vitro studies also show that components of cinnamon control angiogenesis associated with the proliferation of cancer cells. Human studies involving control subjects and subjects with metabolic syndrome, type 2 diabetes mellitus, and polycystic ovary syndrome all show beneficial effects of whole cinnamon and/or aqueous extracts of cinnamon on glucose, insulin, insulin sensitivity, lipids, antioxidant status, blood pressure, lean body mass, and gastric emptying. However, not all studies have shown positive effects of cinnamon, and type and amount of cinnamon, as well as the type of subjects and drugs subjects are taking, are likely to affect the response to cinnamon. In summary, components of cinnamon may be important in the alleviation and prevention of the signs and symptoms of metabolic syndrome, type 2 diabetes, and cardiovascular and related diseases.

Cinnamomum cassia bark in two herbal formulas increases life span in Caenorhabditis elegans via insulin signaling and stress response pathways

Background

Proving the efficacy and corresponding mode of action of herbal supplements is a difficult challenge for evidence-based herbal therapy. A major hurdle is the complexity of herbal preparations, many of which combine multiple herbs, particularly when the combination is assumed to be vitally important to the effectiveness of the herbal therapy. This issue may be addressed through the use of contemporary methodology and validated animal models.

Methods and Principal Findings

In this study, two commonly used traditional herbal formulas, Shi Quan Da Bu Tang (SQDB) and Huo Luo Xiao Ling Dan (HLXL) were evaluated using a survival assay and oxidative stress biomarkers in a well-established C. elegans model of aging. HLXL is an eleven herb formula modified from a top-selling traditional herbal formula for the treatment of arthritic joint pain. SQDB consists of ten herbs often used for fatigue and energy, particularly in the aged. We demonstrate here that SQDB significantly extend life span in a C. elegans model of aging. Among all individual herbs tested, two herbs Cinnamomum cassia bark (Chinese pharmaceutical name: Cinnamomi Cortex, CIN) and Panax ginseng root (Chinese pharmaceutical name: Ginseng Radix, GS) significantly extended life span in C. elegans. CIN in both SQDB and HLXL formula extended life span via modulation of multiple longevity assurance genes, including genes involved in insulin signaling and stress response pathways. All the life-span-extending herbs (SQDB, CIN and GS) also attenuated levels of H₂O₂ and enhanced small heat shock protein expression. Furthermore, the life span-extending herbs significantly delayed human amyloid beta (Aβ)-induced toxicity in transgenic C. elegans expressing human Aβ.

Conclusion/Significance

These results validate an invertebrate model for rapid, systematic evaluation of commonly used Chinese herbal formulations and may provide insight for designing future evidence-based herbal therapy(s).