To what extent does cinnamon administration improve the glycemic and lipid profiles?

Intermittent fasting in the management of diabetes: a review of glycemic control and safety

Intermittent fasting (IF) regimens have emerged as a dietary tool to improve the glycemic profile, but a critical appraisal of clinical studies assessing the effects of IF regimens in patients with diabetes is needed. Thus, this review encompasses clinical studies examining the impact of different IF regimens on markers of glycemic control in patients with diabetes. Furthermore, clinical nuances relative to pharmacological treatment are also addressed, mainly insulin therapy, to discuss the risk of hypoglycemic events. Only a handful of clinical studies have investigated the effects of IF on patients with diabetes. Overall, IF regimens may elicit modest benefits on glycemic parameters in patients with diabetes, but their effects are not necessarily greater than those of control diets. Last, although IF regimens may be considered safe for patients receiving insulin therapy within interventional and observational research, markers of glycemic control must be constantly monitored in clinical practice to reduce the risk of hypoglycemia and its related complications.

Effects of cinnamon supplementation on metabolic biomarkers in individuals with type 2 diabetes: a systematic review and meta-analysis

CONTEXT

The global prevalence of type 2 diabetes mellitus (DM2) has been rising significantly over the years. Recent studies have shown beneficial effects of cinnamon on metabolic biomarkers.

OBJECTIVE

The objective of this review was to assess the effect of cinnamon supplementation on metabolic biomarkers in patients with DM2.

DATA SOURCES

The Pubmed/MEDLINE, Cochrane CENTRAL, and Embase databases were searched up to November 10, 2022.

DATA EXTRACTION

A systematic search was performed for randomized controlled trials (RCTs) evaluating the effect of cinnamon supplementation on metabolic biomarkers, in adults and the elderly with DM2, and comparing the data for a cinnamon intervention group with that for a placebo group or a control group. The main exclusion criteria were studies (1) with other types of diabetes (ie, gestational diabetes or type 1 diabetes), (2) without cinnamon consumption, (3) that did not evaluate metabolic biomarkers, or (4) in vitro and animal studies. Two researchers independently screened 924 records, evaluated full-text studies, extracted data, and appraised their quality. A third researcher was consulted to resolve any discrepancies. The data were pooled using random-effects models and expressed as the weighted mean difference (WMD) with 95% CI. Heterogeneity was assessed using Cochran's Q test and quantified using I2 statistics. Risk of bias was assessed using the Joanna Briggs Institute (JBI) instrument. Sensitivity analysis and the GRADE system were used to assess the robustness and certainty of the findings.

DATA ANALYSIS

In total, 28 RCTs with a duration ranging from 30 to 120 days and a total enrollment of 3054 patients with DM2 were included. Participants consuming cinnamon showed a significant reduction in fasting blood glucose (FBG) (WMD: -15.26 mg/dL; 95% CI: -22.23 to -8.30; I2 = 88%), postprandial glucose (WMD: -39.22 mg/dL; 95% CI: -63.90 to -14.55; I2 = 100%), HbA1c (WMD: -0.56 mg/dL; 95% CI: -0.99 to -0.13; I2 = 94%), and HOMA-IR (WMD = -0.76, 95% CI: -1.13 to -0.39; I2 = 22%) compared with the control group. An intervention of cinnamon in capsule form reduced FBG (WMD:-18.43 mg/dL, 95% CI: -26.32 to -10.53; I2 = 89%), postprandial glucose (WMD: -44.83 mg/dL, 95% CI: -70.67 to -18.99; I2 = 100%), HbA1c (WMD: -0.56 mg/dL, 95% CI: -1.02 to -0.09; I2 = 94%), total cholesterol (WMD: -13.39 mg/dL; 95% CI: -24.71 to -2.07; I2 = 96%), LDL-C (WMD: -6.49 mg/dL, 95% CI: -12.69 to -0.29; I2 = 92%), and triglycerides (WND: -19.75 mg/dL; 95% CI, -33.71 to -5.80; I2 = 88%). Both doses (≤2 g/day and >2 g/day) reduced FBG and postprandial glucose. Only cinnamon doses of ≤2 g/day reduced HbA1c (WMD: -0.68 mg/dL, 95% CI: -1.16 to -0.1; I2 = 92%), HOMA-IR (WMD: -0.94 mg/dL; 95% CI: -1.21 to -0.67; I2 = 0%), and BMI (WMD: -1.18 kg/m2; 95% CI: -1.97 to -0.39; I2 = 0%).

CONCLUSION

The data suggest that cinnamon improves the glycemic and lipid profile and reduces the BMI, particularly in DM2 patients who receive cinnamon supplementation in capsule form and at a dose of ≤2 g/day.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022370332.

Cinnamon: a nutraceutical supplement for the cardiovascular system

Common therapies for cardiovascular diseases (CVDs) are associated with wide side effects. Thus, herbal medicines have been regarded due to fewer side effects, availability, cultural beliefs, and being cheap. For thousand years, herbal medicine has been used for bacterial infections, colds, coughs, and CVDs. Cinnamon bark contains phenolic compounds such as cinnamaldehyde and cinnamic acid with protective properties which can reduce the risk of cardiovascular diseases, cardiac ischemia and hypertrophy, and myocardial infarction. Furthermore, cinnamon has antioxidant and anti-inflammatory properties and exhibits beneficial effects on the complications of diabetes, obesity, hypercholesterolemia, and hypertension which cause CVDs. Although the protective effects of cinnamon on the heart have been reported in many studies, it needs more clinical studies to prove the pharmaceutical and therapeutic efficacy of cinnamon on risk factors of CVDs.

Is breakfast consumption detrimental, unnecessary, or an opportunity for health promotion? A review of cardiometabolic outcomes and functional food choices

Breakfast consumption is generally considered a health-promoting habit for cardiometabolism, particularly with regard to chrononutrition. Glucose uptake is enhanced by proper insulin secretion triggered by the pancreatic clock, averting metabolic dysregulation related to insulin resistance. Breakfast skipping, in turn, is often considered a behaviour detrimental to health, in part due to putative inverse metabolic actions compared to breakfast consumption, such that breakfast skipping may promote circadian desynchrony. However, most ill health concerns about breakfast skipping are inferred from observational research, and recent well-controlled randomized clinical trials have shown benefits of breakfast skipping for cardiovascular risk factors. Accordingly, this review describes the effects of breakfast consumption versus breakfast skipping on cardiovascular risk factors (blood pressure and glycaemic and lipid indices). In addition, the view of breakfast consumption as an opportunity for functional food ingestion is considered to provide further insights into decision-making practice. Collectively, both breakfast consumption and breakfast skipping can be considered viable habits, but they depend on individual preferences, planning, and the specific foods being consumed or omitted. When consumed, breakfast should consist primarily of functional foods typical for this meal (e.g., eggs, dairy products, nuts, fruits, whole grains, coffee, tea, etc.). While breakfast consumption aligns with chrononutrition principles, breakfast skipping can contribute to a calorie deficit over time, which has the potential for widespread cardiometabolic benefits for patients with overweight/obesity. The concepts and practical considerations discussed in the present review may aid health care personnel in personalising breakfast consumption recommendations for diverse patient populations.

Association between dietary glycemic index and non-alcoholic fatty liver disease in patients with type 2 diabetes mellitus

Objective

Managing dietary glycemic index (GI) deserves further attention in the interplay between non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM). This study aimed to evaluate the relationship between dietary GI and the odds of NAFLD in patients with T2DM.

Methods

A cross-sectional study was carried out between April 2021 and February 2022, including 200 participants with T2DM aged 18-70 years, of which 133 had NAFLD and 67 were in the non-NAFLD group. Cardiometabolic parameters were analyzed using standard biochemical kits and dietary intake was assessed using a validated food frequency questionnaire. Binary logistic regression was applied to explore odds ratios (ORs) and 95% confidence intervals (CIs) for NAFLD according to tertiles of dietary GI.

Results

Highest vs. lowest tertile (< 57 vs. > 60.89) of energy-adjusted GI was not associated with the odds of having NAFLD (OR 1.25, 95% CI = 0.6-2.57; P-trend = 0.54) in the crude model. However, there was an OR of 3.24 (95% CI = 1.03-10.15) accompanied by a significant trend (P-trend = 0.04) after full control for potential confounders (age, gender, smoking status, duration of diabetes, physical activity, waist circumference, HbA1c, triglycerides, total cholesterol, dietary intake of total carbohydrates, simple carbohydrates, fat, and protein).

Conclusion

High dietary GI is associated with increased odds of NAFLD in subjects with T2DM. However, interventional and longitudinal cohort studies are required to confirm these findings.

The Effect of Cinnamon on Glycolipid Metabolism: A Dose-Response Meta-Analysis of Randomized Controlled Trials

(1) Background: The effect of cinnamon on the regulation of glycolipid levels in type 2 diabetic patients is still controversial, and there is a lack of research on the dose-response relationship between cinnamon and glycolipid indicators in type 2 diabetic patients. (2) Methods: This dose-response meta-analysis was performed to explore the effect of the cinnamon intervention on glycolipid metabolism. We conducted a comprehensive database search for literature published before November 2022. Nonlinear models were used for dose-response relationship analysis. (3) Results: We identified that a cinnamon intervention was effective in controlling triglyceride (TG) levels (mean difference = -7.31; 95%CI: -12.37, -2.25, p = 0.005) and low-density lipoprotein cholesterol (LDL-C) levels (mean difference = -6.78; 95%CI: -11.35, -2.22, p = 0.004) in type 2 diabetic patients; however, it also was able to increase high-density lipoprotein cholesterol (HDL-C) levels in patients with type 2 diabetes (mean difference = 1.53; 95%CI: 1.01, 2.05, p < 0.001). However, the cinnamon intervention had no significant effect on the level of fasting blood glucose, glycated hemoglobin (HbA1c), or total cholesterol (TC) levels. We found a significant effect of the cinnamon intervention dose on the TG level (p-nonlinearity = 0.016) and LDL-C (p-nonlinearity = 0.019) in the nonlinear dose-response analysis. In the subgroup analysis, we found a hypoglycemic effect with the cinnamon dose ≤1200 mg (mean difference = -11.1, 95%CI: -14.64, -7.58, p < 0.001). (4) Conclusion: Cinnamon intervention may be beneficial in lowering TG and LDL-C levels while enhancing HDL-C levels, and the dosage of the intervention was an important factor in influencing the TG and LDL-C levels.

The effect of cinnamon supplementation on glycemic control in patients with type 2 diabetes or with polycystic ovary syndrome: an umbrella meta-analysis on interventional meta-analyses

BACKGROUND

Several meta-analyses reported glycemic-lowering effects of cinnamon, while others reported conflicting findings. In the present study, we aimed to perform an umbrella meta-analysis of previous interventional meta-analyses on the effects of cinnamon on glycemic control in patients with type 2 diabetes (T2D) or with polycystic ovary syndrome (PCOS).

METHODS

Relevant studies were searched in PubMed, Scopus, EMBASE, Web of Science, and Google Scholar up to June 2022. Meta-analyses of randomized clinical trials (RCTs) investigating the effects of cinnamon on glycemic indices including fasting plasma glucose (FPG), homeostatic model assessment for insulin resistance (HOMA-IR), insulin, and hemoglobin A1C (HbA1c) were included. Random-effects models were used to perform the umbrella meta-analysis and pool the weighted mean difference (WMD) or standardized mean difference (SMD) and their 95% confidence intervals (CI).

RESULTS

Overall, 11 meta-analyses of RCTs were included. Cinnamon supplementation was effective in reducing serum FPG (WMD: -10.93 mg/dL; 95%CI: -16.22, -5.65; SMD: -0.86; 95%CI: -1.19, -0.52), insulin (WMD: -2.01 IU/mL; 95%CI: -3.96, -0.07; SMD: -0.61; 95%CI: -0.93, -0.30), HOMA-IR levels (WMD: -0.61; 95%CI: -0.91, -0.31; SMD: -0.78; 95%CI: -1.26, -0.30), and HbA1c (WMD: -0.10%; 95%CI: -0.17, -0.03).

CONCLUSION

Cinnamon can be used as an anti-diabetic agent and an add-on treatment to control glycemic indices among patients with T2D or PCOS.

Efficacy of cinnamon supplementation on glycolipid metabolism in T2DM diabetes: A meta-analysis and systematic review

Background: Cinnamon is a spice used in cooking and in large quantities as a medical complement with hypoglycemic and lipid-lowering properties. The potential pharmacological mechanisms underlying cinnamon's anti-diabetic properties and its active ingredients have not been adequately determined. The current meta-analysis aims to systematically review the potential pharmacological mechanisms underlying the hypoglycemic and hypolipidemic efficacy of cinnamon administration and summarize clinical recommendations of cinnamon and its active ingredients. Method: Relevant randomized clinical trials (RCTs) were identified through a literature search that spanned the years January 2005 to April 2022. Retrieve electronic databases including Web of Science, PubMed, Embase, Medline, and the Cochrane Library. To obtain standardized mean differences (SMDs), continuous outcomes were pooled and 95 percent confidence intervals (CIs) were provided. Categorical outcomes were aggregated to calculate relative risks (RRs) and were accompanied by 95% CIs. Heterogeneity was measured using the Cochrane Q-test and I² statistics, with a p < 0.05 considered as substantial heterogeneity. If I² was less than 50%, a fixed effect model was employed; otherwise, a random effect model was used. Subgroup analyses and sensitivity analyses were performed to identify the origins of heterogeneity. Publication bias was retrieved by means of a funnel-plot analysis and Egger's test. The data were analyzed using revman (V.5.3) and stata (V.15) software packages. Results: These 16 RCTs included a total of 1,020 patients who were followed for a duration ranging from 40 days to 4 months. According to the current meta-analysis results, glycolipid levels in diabetic individuals who received cinnamon were significantly improved as compared to those who got placebo (All p < 0.05). An adverse effect was only detected in one patient. Conclusion: These findings imply that cinnamon has a significant influence on lipid and glucose metabolism regulation. An even more pronounced effect was observed in patients with HbA1c of 8%. The results of this study suggested that cinnamon may be utilized as hypoglycemic and lipid-lowering supplement in clinical settings with a guaranteed safety profile.Systematic Review Registration: [PROSPERO], identifier [CRD42022322735].

Effects of the 5:2 intermittent fasting diet on non-alcoholic fatty liver disease: A randomized controlled trial

Background and aims

Dietary regimens are crucial in the management of non-alcoholic fatty liver disease (NAFLD). The effects of intermittent fasting (IF) have gained attention in this regard, but further research is warranted. Thus, we aimed to ascertain the overall effects of the 5:2 IF diet (5 days a week of normal food intake and 2 consecutive fasting days) in patients with NAFLD compared to a control group (usual diet).

Methods and results

A 12-week randomized controlled trial was performed to evaluate the effects of the 5:2 IF diet on anthropometric indices, body composition, liver indices, serum lipids, glucose metabolism, and inflammatory markers in patients with NAFLD. The IF group (n = 21) decreased body weight (86.65 ± 12.57–82.94 ± 11.60 kg), body mass index (30.42 ± 2.27–29.13 ± 1.95 kg/m²), waist circumference (103.52 ± 6.42–100.52 ± 5.64 cm), fat mass (26.64 ± 5.43–23.85 ± 5.85 kg), fibrosis (6.97 ± 1.94–5.58 ± 1.07 kPa), steatosis scores/CAP (313.09 ± 25.45–289.95 ± 22.36 dB/m), alanine aminotransferase (41.42 ± 20.98–28.38 ± 15.21 U/L), aspartate aminotransferase (34.19 ± 10.88–25.95 ± 7.26 U/L), triglycerides (171.23 ± 39.88–128.04 ± 34.88 mg/dl), high-sensitivity C-reactive protein (2.95 ± 0.62 −2.40 ± 0.64 mg/L), and cytokeratin-18 (1.32 ± 0.06–1.19 ± 0.05 ng/ml) values compared to the baseline and the end of the control group (n = 23)—p ≤ 0.05 were considered as significant. However, the intervention did not change the levels of high-density lipoprotein cholesterol, total cholesterol, low-density lipoprotein cholesterol, fasting blood sugar, insulin, HOMA-IR, and total antioxidant capacity.

Conclusion

Adhering to the 5:2 IF diet can reduce weight loss and related parameters (fat mass and anthropometric indicators of obesity), as well as hepatic steatosis, liver enzymes, triglycerides, and inflammatory biomarkers in patients with NAFLD.

Upregulation of GLUT4 and PI3K, and downregulation of GSK3 mediate the anti-hyperglycemic effects of proanthocyanidins

Diabetes mellitus is the most common chronic metabolic disorder worldwide. The present study was designed to investigate the potential role of cinnamon bark extract oligomeric proanthocyanidins (OPCs) in controlling streptozotocin (STZ)-induced hyperglycemia and to clarify the underlying molecular mechanisms underlying its effects. For this purpose, 60 male rats were equally divided into six groups as follows: The normal control group; OPC control group (non-diabetic rats treated with OPC at 300 mg/kg orally for 21 days); the untreated diabetic control group; the wortmannin control group [diabetic rats treated with wortmannin at 1 mg/kg, intraperitoneal (i.p.) on the final day of the experiment]; the OPC diabetic group (diabetic rats treated with OPC at 300 mg/kg orally for 21 days); and the OPC diabetic + wortmannin co-treated group (diabetic rats treated with OPC at 300 mg/kg/day for 21 consecutive days and then 24 h after the final OPC dose treated with a single wortmannin injection at 1 mg/kg, i.p.). The results indicated that OPC ameliorated the diabetic state, as evidenced by a significant decrease in serum glucose levels, and a significant increase in the levels of insulin, amylin, insulin receptor phosphorylation, glycogen and glucose transporter-4 translocation; it also improved the lipid profile in STZ-diabetic rats. On the whole, the findings of the present study provide biochemical evidence that OPC treatment is effective as an anti-diabetic and anti-hyperlipidemic agent by enhancing glucose uptake through the activation of insulin receptor kinase activity and the PI3K/Akt pathway.

Safety of Cinnamon: An Umbrella Review of Meta-Analyses and Systematic Reviews of Randomized Clinical Trials

Purpose: Many evidence-based studies have indicated that cinnamon has therapeutic effects. However, it may not be entirely safe and its adverse effects may be ignored. The present umbrella review was conducted to elucidate the safety of cinnamon.

Methods: Pertinent meta-analyses and systematic reviews of randomized controlled trials on cinnamon use in humans were identified by searching PubMed, EMBASE, and the Cochrane Library from their inception to September 15, 2021. All meta-analyses and systematic reviews on the safety or adverse effects of cinnamon were considered. PRISMA 2020 was used as the standard of reporting (PRISMA registration ID: 286746).

Results: We identified three meta-analyses and one systematic review that described the safety of cinnamon. The quality of the meta-analysis and systematic reviews was evaluated using “Assessing the Methodological Quality of Systematic Reviews.” Their quality was rated as low in two (50%) instances and moderate in two (50%). There were no significant toxic- or side effects between cinnamon group and placebo group regardless of dose and duration.

Conclusion: There is evidence to support that the use of cinnamon has no adverse reactions. It can improve the health status of patients as an adjuvant treatment. Future studies exploring better profile risks and protective factors for cinnamon use-related adverse effect are needed, in order that preventive approaches can be developed.

Some Common Medicinal Plants with Antidiabetic Activity, Known and Available in Europe (A Mini-Review)

Diabetes is a metabolic disease that affected 9.3% of adults worldwide in 2019. Its co-occurrence is suspected to increase mortality from COVID-19. The treatment of diabetes is mainly based on the long-term use of pharmacological agents, often expensive and causing unpleasant side effects. There is an alarming increase in the number of pharmaceuticals taken in Europe. The aim of this paper is to concisely collect information concerning the few antidiabetic or hypoglycaemic raw plant materials that are present in the consciousness of Europeans and relatively easily accessible to them on the market and sometimes even grown on European plantations. The following raw materials are discussed in this mini-review: Morus alba L., Cinnamomum zeylanicum J.Presl, Trigonella foenum-graecum L., Phaseolus vulgaris L., Zingiber officinale Rosc., and Panax ginseng C.A.Meyer in terms of scientifically tested antidiabetic activity and the presence of characteristic biologically active compounds and their specific properties, including antioxidant properties. The characteristics of these raw materials are based on in vitro as well as in vivo studies: on animals and in clinical studies. In addition, for each plant, the possibility to use certain morphological elements in the light of EFSA legislation is given.

Healthy Eating Index-2015 and Dietary Total Antioxidant Capacity as Predictors of Prediabetes: A Case-Control Study

BACKGROUND

The overall dietary quality, as well as the dietary total antioxidant capacity (DTAC), deserves central attention in the management of borderline high glucose levels since nonpharmacological strategies are imperative in this regard. Thus, we aimed to investigate the association between prediabetes with dietary quality and DTAC.

METHODS

A case-control study was conducted on 49 patients with prediabetes and 98 controls. Demographics, anthropometric measures, and fasting blood glucose levels of all participants were obtained. Participants completed a validated 80-item food frequency questionnaire (FFQ). DTAC scores were generated using FFQ data, and Healthy Eating Index-2015 (HEI-2015) was used as a diet quality index. The lowest tertile of HEI-2015 and DTAC was considered as the reference category, and logistic regression was used to estimate the relationship between prediabetes with HEI-215 and DTAC.

RESULTS

Mean age and body mass index of participants were 47.42 ± 15.98 years and 27.90 ± 4.96 kg/m2. Patients with prediabetes had lower DTAC scores when compared to controls (11.86 ± 5.77 and 17.81 ± 12.08, P = 0.01). There was a significant inverse association between the highest tertile of the DTAC score when compared with the lowest tertile in crude (OR = 0.11; 95% CI: 0.03-0.43), age-adjusted (OR = 0.13; 95% CI: 0.03-0.48), and fully adjusted (OR = 0.09; 95% CI: 0.02-0.53) models. In contrast, there was no difference between HEI-2015 in patients with prediabetes when compared to controls (74.41 ± 8.91 and 74.41 ± 9.35, respectively; P = 0.85). Correspondingly, no difference was observed between the highest tertile of the HEI-2015 score when compared with the lowest tertile in crude (OR = 1.23; 95% CI: 0.53-2.86), age-adjusted (OR = 1.17; 95% CI: 0.48-2.82), and fully adjusted (OR = 1.53; 95% CI: 0.56-4.16) models.

CONCLUSION

This study demonstrates a clear association between prediabetes with less DTAC, but not with HEI-2015.

trans-Cinnamaldehyde Prevents Oxidative Stress-Induced Apoptosis in V79-4 Chinese Hamster Lung Fibroblasts through the Nrf2-Mediated HO-1 Activation

Oxidative stress, which is characterized by overproduction of reactive oxygen species (ROS), is considered a major risk factor associated with fibroblast death in severe lung diseases such as idiopathic pulmonary fibrosis. trans-Cinnamaldehyde (tCA), the major phytochemical constituent in cinnamon, is known to possess strong anti-oxidant activity. However, whether tCA can defend lung fibroblasts against oxidative injury remains to be elucidated. Therefore, this study was conducted to investigate the protective effects of tCA on oxidative stress in V79-4 Chinese hamster lung fibroblasts. The current results showed that tCA inhibited hydrogen peroxide (H₂O₂)-induced cytotoxicity by blocking abnormal accumulation of ROS in V79-4 Chinese hamster lung fibroblasts. tCA attenuated apoptosis by suppressing of mitochondrial dysfunction and cytosolic release of cytochrome c, increasing the rate of Bcl-2/Bax expression and reducing the activity of caspase-9 and caspase-3 in H₂O₂-stimulated V79-4 cells, suggesting that tCA protected V79-4 cells from the induction of mitochondria-mediated apoptosis by H₂O₂. Additionally, the activation of nuclear factor-erythroid-2-related factor 2 (Nrf2) was markedly promoted by tCA in the presence of H₂O₂, which was associated with the enhanced expression of heme oxygenase-1 (HO-1). However, inhibiting the activity of HO-1 by zinc protoporphyrin IX, a potent inhibitor of HO-1, eliminated the ROS scavenging and protective effects of tCA, indicating that tCA was able to protect V79-4 lung fibroblasts from H₂O₂-induced oxidative stress by activating the Nrf2 signaling pathway. Therefore, it is suggested that tCA may be useful as a candidate for the treatment of oxidative stress-mediated lung injuries in the future.

Cinnamon as Dietary Supplement Caused Hyperlipidemia in Healthy Rats

Objective

Cinnamon is a cooking spice and a medicinal herb. It is increasingly used as a health supplement due to its perceived benefit to prevent and or manage type 2 diabetes and metabolic disorders. However, it is unclear if regular consumption of this medicinal plant will interfere with normal physiological functions. Therefore, this study investigated the impact of daily cinnamon supplements on glucose and lipid metabolic profiles in healthy rats.

Methods

Male rats (Sprague Dawley, 8 weeks) were supplied with cinnamon in their diet (equivalent to ∼1 g/day in humans) for two weeks. Blood glucose and lipid levels, as well as metabolic markers in both liver and abdominal white adipose tissue, were measured.

Results

Cinnamon significantly increased fat mass and blood cholesterol and low-density lipoprotein (LDL) levels, but reduced fasting blood glucose level by 12%. Liver functional enzymes were normal in rats consuming cinnamon. However, several lipid metabolic markers were impaired which may contribute to dyslipidemia, including two main switches for energy metabolism (sirtuin 1 and peroxisome proliferator-activated receptor-gamma coactivator-1α) and the LDL receptor. However, de novo lipid synthesis enzymes and inflammatory markers were also reduced in the liver by cinnamon treatment, which may potentially prevent the development of steatosis. Markers for lipid oxidation were downregulated in fat tissue in cinnamon-treated rats, contributing to increased fat accumulation.

Conclusion

Daily low-dose cinnamon supplementation seems to promote abdominal adipose tissue accumulation and disturb lipid homeostasis in healthy rats, raising the concerns regarding daily use in healthy people.

p53 Rather Than β-Catenin Mediated the Combined Hypoglycemic Effect of Cinnamomum cassia (L.) and Zingiber officinale Roscoe in the Streptozotocin-Induced Diabetic Model

Background: The antioxidant, hypoglycemic, and insulin-enhancing effects of ginger and cinnamon were previously confirmed in experimental and human studies, while the combined effect of ginger and cinnamon was not thoroughly investigated until now.

Objectives: This study was designed to assess the antidiabetic effect of combined administration of ginger (Zingiber officinale Roscoe) and cinnamon (Cinnamomum cassia L.) in streptozotocin (STZ)-induced diabetic rats compared to metformin and to explain the mechanism behind this effect.

Materials and methods: STZ was utilized to induce diabetes mellitus in male Sprague–Dawley rats. Assessments of fasting blood glucose level (BGL), the total antioxidant capacity (TAC), serum insulin, HOMA-IR, and HOMA–β cells were performed. Pancreatic gene expression of β-catenin and p53 was assessed using RT-PCR. Assessment of histopathological alterations of pancreatic islet cells was performed using routine and immunohistochemical techniques.

Results: BGL significantly decreased (p = 0.01), while serum insulin and TAC significantly increased (p < 0.001) in both metformin- and ginger plus cinnamon–treated groups compared to the untreated diabetic group. HOMA–β cell index significantly increased (p = 0.001) in ginger plus cinnamon, indicating their enhancing effect on insulin secretion in diabetic conditions. p53 gene expression was significantly upregulated (p < 0.001), while β-catenin was insignificantly downregulated (p = 0.32) in ginger plus cinnamon–treated groups. Insulin immunoexpression in β cells significantly increased (p = 0.001, p = 0.004) in metformin- and ginger plus cinnamon–treated groups, respectively.

Conclusions: The combined administration of ginger and cinnamon has a significant hypoglycemic and antioxidant effect in STZ-induced diabetes mostly through enhancing repair of islet cells mediated via upregulation of pancreatic p53 expression. Therefore, testing this effect in diabetic patients is recommended.

Efficacy of Cinnamon as an Adjuvant in Reducing the Glycemic Biomarkers of Type 2 Diabetes Mellitus: A Three-Month, Randomized, Triple-Blind, Placebo-Controlled Clinical Trial

The major aim of this randomized, placebo-controlled, triple-blind clinical trial was to evaluate the efficacy of cinnamon as an adjuvant treatment in reducing glycemic levels in people with type 2 diabetes, compared to a placebo. The study was conducted between August and December 2019, with 160 people with type 2 diabetes, in five Primary Health Units, in Parnaíba, Brazil. Inclusion criteria were: persons of both genders using oral antidiabetic agents, with glycated hemoglobin ≥ 6.0%, and between 18 and 80 years of age. The primary outcome was change in glycated hemoglobin levels after 90 days of intervention. Other biomarkers evaluated were fasting blood glucose, insulin level, and HOMA-IR index. Participants were divided equally into two groups of 80 individuals each, and were given 3 g capsules of either cinnamon or placebo to be taken in combination with their usual oral antidiabetic agents. After 90 days, participants in the cinnamon group had statistically significant reductions of 0.2% of glycated hemoglobin and 0.55 mmol/L of fasting venous glucose, when compared with the placebo group. Cinnamon reduced the glycemic measures of persons with type 2 diabetes, albeit with modest reductions. TRIAL: RBR-2KKB6D.

Acute Effects of Cinnamon Spice on Post-prandial Glucose and Insulin in Normal Weight and Overweight/Obese Subjects: A Pilot Study

Clinical studies and meta-analyses have supported the notion that consuming cinnamon spice long term can have beneficial effects in individuals with normal glucose homeostasis and varying degrees of glucose intolerance including type 2 diabetes. The objective of this study was to evaluate the acute effect of cinnamon on the post-prandial responses to a typical American breakfast in normal and overweight/obese participants (ClinicalTrials.gov registration No. NCT04686552). The consumption of a single dose of 6 g of cinnamon added to oatmeal prepared with milk resulted in a significant reduction of one of our primary outcomes post-prandial insulin response (niAUC_0−180min) in overweight/obese participants compared to control consuming breakfast without cinnamon. We also performed exploratory analysis of secondary outcomes. In normal weight participants, we observed a decrease of post-prandial glucagon response (niAUC_0−180min and glucagon levels at 60–120 min) and C-peptide response (30 min) comparing breakfast with to without cinnamon. Cinnamon consumption did not change post-prandial glycemic response in normal weight participants, but increased 60 min post-prandial glucose in overweight/obese participants compared to control. In summary, cinnamon consumption differentially affected post-prandial hormonal responses in normal and overweight/obese participants.

Medicinal plants and bioactive natural compounds as inhibitors of HMG-CoA reductase: A literature review

Cardiovascular diseases (CVDs) are one of the most important causes for mortality worldwide. Elevated levels of total cholesterol, and particularly LDL-cholesterol (LDL-C) are the main risk factor for acute myocardial infarction (AMI) and ischemic heart disease. The risk of CVDs could be reduced by decreasing the elevated cholesterol levels. β-hydroxy β-methylglutaryl-CoA reductase (HMGCoAR) is the primary and rate-limiting enzyme in the cholesterol biosynthesis pathway. Recently, the crucial role of nutraceuticals in maintaining normal physiological function was established. Nutraceuticals play an important role in preventing several non-communicable diseases such as obesity, CVDs, cancer, diabetes, and reducing hyperlipidemia. Although the effect of nutraceuticals and herbal medicine on CVDs and dyslipidemia was previously investigated thoroughly, the effect of these natural products on HMGCoAR as one of the important enzymes involved in CVDs etiopathogenesis has not yet been investigated. Therefore, the major aim of this paper was to review the effects of nutraceuticals and medicinal plants on HMGCoAR. Results indicate that different types of natural foods, isolated nutrients, herbal products, and dietary supplements as nutraceuticals decrease the expression and activity of HMGCoAR. This review shows that medicinal plants and nutraceuticals could be used to decrease HMGCoAR activity as accessible and convenient and economical natural compounds to prevent dyslipidemia and CVDs.

The effect of cinnamon supplementation on glycemic control in women with polycystic ovary syndrome: A systematic review and meta-analysis

Several clinical trials have identified glycemic-lowering effects of cinnamon, while other studies have reported conflicting findings. A comprehensive systematic search on Embase, PubMed, Scopus, Web of Science, and Cochrane Library was conducted using defined keywords in any language through June 2020. Studies that compared the effect of cinnamon with placebo on insulin resistance (IR) indices, as the primary outcome, in women with polycystic ovary syndrome (PCOS) were considered eligible. Standard Mean difference (SMD) (with 95% confidence intervals) for endpoints were calculated using the random-effects model. Finally, five RCTs which met the criteria were included in the meta-analysis. After pooling data, cinnamon supplementation significantly reduced homeostatic model assessment for insulin resistance (HOMA-IR) scores in women with PCOS (SMD: -0.84, 95% CI: -1.52, -0.16, p = .010). Cinnamon supplementation likely improves certain IR markers in patients with PCOS. PRACTICAL APPLICATIONS: There are controversies reports for cinnamon intake, which animal models have suggested that it decreases IR via promotion of insulin action, stimulating insulin signaling pathways, and enhancing insulin sensitivity. This study provides comprehensive information about the effect of cinnamon on insulin resistance (IR) indices in women with PCOS. In this regard, our results indicated that cinnamon supplementation significantly reduced homeostatic model assessment for insulin resistance (HOMA-IR) scores in women with PCOS. Therefore, consumption of cinnamon can be safe and this can be a useful recommendation for improving IR and promotion of healthy life which indeed are the potential or actual uses of this research.

Beyond Fish Oil Supplementation: The Effects of Alternative Plant Sources of Omega-3 Polyunsaturated Fatty Acids upon Lipid Indexes and Cardiometabolic Biomarkers-An Overview

Cardiovascular diseases remain a global challenge, and lipid-associated biomarkers can predict cardiovascular events. Extensive research on cardiovascular benefits of omega-3 polyunsaturated fatty acids (n3-PUFAs) is geared towards fish oil supplementation and fish-rich diets. Nevertheless, vegetarianism and veganism are becoming more popular across all segments of society, due to reasons as varied as personal, ethical and religious values, individual preferences and environment-related principles, amongst others. Due to the essentiality of PUFAs, plant sources of n3-PUFAs warrant further consideration. In this review, we have critically appraised the efficacy of plant-derived n3-PUFAs from foodstuffs and supplements upon lipid profile and selected cardiometabolic markers. Walnuts and flaxseed are the most common plant sources of n3-PUFAs, mainly alpha-linolenic acid (ALA), and feature the strongest scientific rationale for applicability into clinical practice. Furthermore, walnuts and flaxseed are sources of fibre, potassium, magnesium, and non-essential substances, including polyphenols and sterols, which in conjunction are known to ameliorate cardiovascular metabolism. ALA levels in rapeseed and soybean oils are only slight when compared to flaxseed oil. Spirulina and Chlorella, biomasses of cyanobacteria and green algae, are important sources of n3-PUFAs; however, their benefits upon cardiometabolic markers are plausibly driven by their antioxidant potential combined with their n3-PUFA content. In humans, ALA is not sufficiently bioconverted into eicosapentaenoic and docosahexaenoic acids. However, evidence suggests that plant sources of ALA are associated with favourable cardiometabolic status. ALA supplementation, or increased consumption of ALA-rich foodstuffs, combined with reduced omega-6 (n6) PUFAs intake, could improve the n3/n6 ratio and improve cardiometabolic and lipid profile.

Pharmaconutrition in the Clinical Management of COVID-19: A Lack of Evidence-Based Research But Clues to Personalized Prescription

A scientific interest has emerged to identify pharmaceutical and nutritional strategies in the clinical management of coronavirus disease 2019 (COVID-19). The purpose of this narrative review is to critically assess and discuss pharmaconutrition strategies that, secondary to accepted treatment methods, could be candidates in the current context of COVID-19. Oral medicinal doses of vitamin C (1-3 g/d) and zinc (80 mg/d elemental zinc) could be promising at the first signs and symptoms of COVID-19 as well as for general colds. In critical care situations requiring parenteral nutrition, vitamin C (3-10 g/d) and glutamine (0.3-0.5 g/kg/d) administration could be considered, whereas vitamin D3 administration (100,000 IU administered intramuscularly as a one-time dose) could possess benefits for patients with severe deficiency. Considering the presence of n-3 polyunsaturated fatty acids and arginine in immune-enhancing diets, their co-administration may also occur in clinical conditions where these formulations are recommended. However, despite the use of the aforementioned strategies in prior contexts, there is currently no evidence of the utility of any nutritional strategies in the management of SARS-CoV-2 infection and COVID-19. Nevertheless, ongoing and future clinical research is imperative to determine if any pharmaconutrition strategies can halt the progression of COVID-19.

Effects of green coffee bean extract on C-reactive protein levels: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND & OBJECTIVE

The effects of green coffee bean extract (GCBE) supplementation on inflammatory biomarkers have been widely spread. The purpose of this article was to assess the impact of GCBE supplementation on C-reactive protein (CRP) levels.

METHODS

The literature search was performed in four databases (Scopus, PubMed, the Cochrane Library, and Google Scholar) to identify studies that examined the influence of GCBE supplementation on CRP levels up to August 2019. Mean and standard deviation (SD) of the outcomes were used to estimate the weight mean difference (WMD) between intervention and control groups for the follow-up period.

RESULTS

Five (5) studies, with 6 arms, reported CRP as an outcome. Statistically, the use of GCBE supplements resulted in a significant change in CRP levels (WMD: -0.017 mg/dL, 95 % CI: -0.032, -0.003, p = 0.018), whose overall findings were obtained from random-effects model. In addition, a significantly greater reduction in CRP was noted for studies with doses of GCBE supplements ≥ 1000 mg/d (WMD: -0.015 mg/dL, 95 % CI: -0.020, -0.010, p < 0.000), length of intervention < 4 weeks (WMD: -0.015 mg/dL, 95 % CI: -0.020, -0.010, p < 0.001), and for non-healthy subjects (WMD: -0.019 mg/dL, 95 % CI: -0.027, -0.011, p < 0.001). Dyslipidemia, hypertension and non-alcoholic fatty liver disease were the ailments of the studies that encompassed non-healthy patients.

CONCLUSIONS

This meta-analysis shows that the use of GCBE supplements resulted in a statistical decrease in CRP levels, mainly for non-healthy subjects. However, due to the limited number of studies, further randomized clinical trials are crucial in this regard.

Trans-cinnamaldehyde protects C2C12 myoblasts from DNA damage, mitochondrial dysfunction and apoptosis caused by oxidative stress through inhibiting ROS production

BACKGROUND

Oxidative stress-induced myoblast damage is one of the major causes of skeletal muscle loss associated with inhibition of myogenic differentiation and muscle dysfunction. Trans-cinnamaldehyde (tCA), the most common essential oil constituent in cinnamon, is known to possess strong anti-oxidant activity. However, it has not been determined whether tCA can protect myoblasts from oxidative damage.

OBJECTIVES

The aim of this study was to investigate the protective effect of tCA against oxidative stress-induced damage in mouse myoblast C2C12 cells.

METHODS

To examine the efficacy of tCA to protect against oxidative damage, cell viability, morphological changes, DNA damage, mitochondrial membrane potential (MMP) analysis, reactive oxygen species (ROS) generation, and Western blotting were applied.

RESULTS

tCA suppressed hydrogen peroxide (H₂O₂)-induced growth inhibition and DNA damage by blocking abnormal ROS accumulation. In addition, tCA attenuated apoptosis by suppressing loss of MMP and cytosolic release of cytochrome c, increasing the rate of Bcl-2/Bax expression and reducing the activity of caspase-3 in H₂O₂-stimulated cells, suggesting that tCA protected C2C12 cells from mitochondria-mediated apoptosis caused by oxidative stress.

CONCLUSION

The results showed that tCA may be useful as a potential treatment for the prevention and treatment of various oxidative stress-related muscle disorders in the future.

Phytochemical and pharmacological review of Cinnamomum verum J. Presl-a versatile spice used in food and nutrition

Cinnamomum verum is the widely used spice for its medicinal and culinary uses since ages. It is native to Sri Lanka and southern India but also distributed in many Asian, Caribbean, Australian and African countries. It is widely used in food preparations and industrial products like candies, chewing gums, mouthwash and toothpaste. It is also used to treat asthma, bronchitis, diarrhea, headache, inflammation and cardiac disorders. Cinnamaldehyde, eugenol, caryophyllene, cinnamyl acetate and cinnamic acid are the major compounds found in its essential oil. These compounds exhibit a wide range of pharmacological activities including antioxidant, antimicrobial, anti-inflammatory, anticancer, antidiabetic, wound healing, anti-HIV, anti-anxiety and antidepressant, etc. This review highlights its comprehensive and up-to-date information on taxonomy, ethnomedicinal uses, phytochemical composition, pharmacological and toxicity activities. Structure-activity relationship, mechanism of action and some research gaps has also been provided. Owing to its immense medicinal importance, more well-designed in-vivo and clinical studies are required.

Cinnamon and its Metabolite Protect the Nigrostriatum in a Mouse Model of Parkinson's Disease Via Astrocytic GDNF

Glial cell line-derived neurotrophic factor (GDNF) has potent neurotrophic effects and is known to promote the dopaminergic (DA) neuronal survival in cellular and animal models of Parkinson's disease (PD). However, long-term ectopic GDNF delivery is associated with long lasting adverse side effects in PD patients. Therefore, finding safer and effective ways to elevate endogenous GDNF levels is an active area of research. This study underlines the importance of sodium benzoate (NaB), a metabolite of commonly-used spice cinnamon, a food-additive and an FDA-approved drug against hyperammonemia, in stimulating GDNF in primary mouse and human astrocytes. Presence of cAMP response element (CRE) in the Gdnf gene promoter, recruitment of CREB to the Gdnf promoter by NaB and abrogation of NaB-mediated GDNF expression by siRNA knockdown of CREB suggest that NaB induces the transcription of Gdnf via CREB. Finally, oral administration of NaB and cinnamon itself increased the level of GDNF in vivo in the substantia nigra pars compacta (SNpc) of normal as well as MPTP-intoxicated mice. Accordingly, cinnamon and NaB treatment protected tyrosine hydroxylase positive neurons in the SNpc and fibers in the striatum, normalized striatal neurotransmitters, and improved locomotor activities in MPTP-intoxicated Gfap^cre mice, but not Gdnf^Δastro mice lacking GDNF in astrocytes. These findings highlight the importance of astroglial GDNF in cinnamon- and NaB-mediated protection of the nigrostriatum in MPTP mouse model of PD and suggest possible therapeutic potential of cinnamon and NaB in PD patients. Graphical abstract Cinnamon metabolite sodium benzoate (NaB) activates cAMP-response element-binding (CREB) via protein kinase A (PKA) in astrocytes. Activated CREB then binds to cAMP-response element (CRE) present in GDNF gene promoter to stimulate the transcription of GDNF in astrocytes. This astrocytic GDNF leads to nigral trophism and protects dopaminergic neurons from MPTP insult.

Beyond tribulus (Tribulus terrestris L.): The effects of phytotherapics on testosterone, sperm and prostate parameters

ETHNO-PHARMACOLOGICAL RELEVANCE

Phytotherapeutic approaches have been widely proposed to improve male health. Despite the well-touted effects of tribulus (Tribulus terrestris L) on men's health, an optimal phytotherapy remains an elusive challenge.

AIM OF THE REVIEW

We sought to critically analyze the evidence in the phytotherapic literature beyond the effects of tribulus on testosterone (T) concentration and sperm analysis to also include indications for prostate health.

MATERIALS AND METHODS

A focused literature search was conducted to include studies published in Cochrane, Pubmed, and Web of Science databases between the years 2002 and 2018.

RESULTS

The use of tribulus and maca (Lepidium meyenii Walp, Brassicaceae) were not scientifically supported to improve serum T levels in men. Moderate evidence supports the use of long Jack (Eurycoma longifolia Jack, Simaroubaceae), mucuna (Mucuna pruriens (L.) DC., Fabaceae), ashwagandha (Withania somnifera (L.) Dunal, Solanaceae), fenugreek (Trigonella foenum-graceum L., Fabaceae), and black seeds (Nigella sativa L., Ranunculaceae) to increase total T and improve seminal parameters. Data suggests an increase in total T with the use of 5000 mg/d of powdered mucuna seed and ashwagandha root (151 and 143 ng/dL, respectively) over a 12-week period in patients with oligozoospermia. The use of mucuna was supported for patients with oligozoospermia to improve sperm parameters, with an increase of 83.3 million/mL observed after use of 5000 mg/d of powdered mucuna seed over a 12-week period. Evidence supporting the use of saw palmetto (Serenoa repens, (W.Bartram) Small, Arecaceae) to improve prostate health remains equivocal; whereas, evidence supporting the use of Pygeum africanum Hook.f., Rosaceae, Urtica dioica L., Urticaceae, beta-sitosterols, pollen extract, onion, garlic, and tomato, appears favorable and promising.

CONCLUSION

Scientific evidence supports the use of mucuna and ashwagandha as phytotherapics for improving serum T concentrations and semen parameters. Despite inconclusive evidence for use of tribulus as a T booster, it may provide advantageous effects on sperm parameters in men with idiopathic infertility. Nutraceutical strategies and some phytotherapics may also be effective to promote prostate health. Popular foodstuffs (onion, garlic, and tomato), nutraceutical agents (pollen extract and beta-sitosterols), and herbal medicines (Pygeum africanum and Urtica dioica) are rational approaches.