Impact of flaxseed intake upon metabolic syndrome indicators in female Wistar rats

The effects of phytochemicals and herbal bio-active compounds on tumour necrosis factor-α in overweight and obese individuals: a clinical review

Obesity is abnormal fat accumulation in the body which acts as a risk factor for various cardiometabolic states. Adipose tissue in excess can release inflammatory factors, including TNF-α and IL-6, and suppress adiponectin production. TNF-α increases the levels of IL-6 and acute phase reactants such as C-reactive protein. Inflammation has a crucial role in developing and progressing various cardiometabolic diseases and a wide range of obesity-related complications. It has been shown that TNF-α has a significant role in the development of insulin resistance. Recently, a growing body of evidence has focused on herbal medicine, phytochemicals and natural bioactive compounds as inexpensive, relatively easy accessible agents with low adverse effects to reduce inflammatory markers such as TNF-α and simultaneously decrease insulin resistance, glucose intolerance, and dyslipidemia in obesity. The main focus of the current review is to summarize the results of the studies, which assessed the effects of phytochemicals and herbal bio-active compounds on serum TNF-α in subjects with overweight or obesity. This review suggests that herbal medicine have favorable effects on the reduction of TNF-α concentration; however, the results were not uniform for different products. Among the reviewed plants, ginger, ginseng, resveratrol, and flaxseed had more promising effects.

Regulation of Apolipoprotein B by Natural Products and Nutraceuticals: A Comprehensive Review

Cardiovascular Disease (CVD) is the most important and the number one cause of mortality in both developing and industrialized nations. The co-morbidities associated with CVD are observed from infancy to old age. Apolipoprotein B100 (Apo B) is the primary apolipoprotein and structural protein of all major atherogenic particles derived from the liver including Very-Low- Density Lipoproteins (VLDL), Intermediate-density Lipoprotein (IDL), and Low-density Lipoprotein (LDL) particles. It has been suggested that measurement of the Apo B concentration is a superior and more reliable index for the prediction of CVD risk than is the measurement of LDL-C. Nutraceuticals and medicinal plants have attracted significant attention as it pertains to the treatment of non-communicable diseases, particularly CVD, diabetes mellitus, hypertension, and Nonalcoholic Fatty Liver Disease (NAFLD). The effect of nutraceuticals and herbal products on CVD, as well as some of its risk factors such as dyslipidemia, have been investigated previously. However, to the best of our knowledge, the effect of these natural products, including herbal supplements and functional foods (e.g. fruits and vegetables as either dry materials, or their extracts) on Apo B has not yet been investigated. Therefore, the primary objective of this paper was to review the effect of bioactive natural compounds on plasma Apo B concentrations. It is concluded that, in general, medicinal plants and nutraceuticals can be used as complementary medicine to reduce plasma Apo B levels in a safe, accessible, and inexpensive manner in an attempt to prevent and treat CVD.

The effects of flaxseed supplementation on metabolic syndrome parameters, insulin resistance and inflammation in ulcerative colitis patients: An open-labeled randomized controlled trial

The present study aimed to evaluate the efficacy of flaxseed supplementation in the management of metabolic syndrome (MetS)-related parameters among the patients with mild-to-moderate ulcerative colitis (UC). A randomized controlled clinical trial was conducted on 70 patients with UC. Participants were randomized in the intervention group, which received 30 g/day ground flaxseed powder or control group. Anthropometric and biochemical variables were assessed at the beginning and end of 12 weeks of intervention. Of the 70 patients enrolled in this study, 64 subjects were included in the final analysis. From baseline to 12 weeks' intervention, flaxseed supplementation resulted in a significant reduction in the serum concentration of insulin (p < .001), HOMA-IR (p < .001), triglyceride (p = .001), total cholesterol (p < .001), and significant increase in the serum levels of HDL (p = .008). Also, we found a significant improvement in the SCCAI score (p < .001), TNF-α (p = .03), and CRP (p < .001) following the flaxseed supplementation. However, we not observed any significant differences between two groups regarding the body weight, BMI, waist circumferences, systolic, and diastolic blood pressure (p > .05). Overall, 12 weeks of flaxseed supplementation resulted in greater improvement in the some MetS-related parameters.

Medicinal Plants and Phytochemicals Regulating Insulin Resistance and Glucose Homeostasis in Type 2 Diabetic Patients: A Clinical Review

Diabetes is a major health problem affecting more than four hundred million adults worldwide. The transition from normal glucose tolerance to type 2 diabetes (T2D) is preceded by increased Insulin resistance (IR), an independent predictor of the development of T2D in high risk (e.g. obese populations, pre-diabetes) individuals. Insulin deficiency resulting from increased IR results in progressive glucose homeostasis dysfunction. Data has shown that IR is affected by many different factors such as genetics, age, exercise, dietary nutrients, obesity, and body fat distribution. One of the most important factors is diet, which plays an essential role in addressing T2D and metabolic syndrome. Nutraceuticals and medicinal plants have been shown to have efficacy in preventing chronic diseases like cancer, non-alcoholic fatty liver disease (NAFLD), cardiovascular disease, diabetes mellitus and metabolic syndrome, likely through the anti-inflammatory properties found in nutraceuticals. However, the effect of these compounds, including traditional plant medicines, herbal formulations or their extracts on IR have not been systematically investigated. The objective of this review was to assess the reported effects of medicinal plants and bioactive natural compounds on IR. The findings confirm that most of the herbal bioactive compounds including resveratrol, garlic, curcumin, cinnamon, ginger, nuts, berberine, anthocyanin, soybean, flaxseed, vegetable oils, and soluble fibers have benefit in their efficacy for decreasing IR, fasting blood sugar (FBS), fasting insulin and HbA1c.

Can the indicators of chronic ethanol consumption be minimized by a continuous flaxseed intake?

The aim of this study was to evaluate the use of flaxseed in animals subjected to ethanol-induced hepatotoxicity. Twenty-four male rats were divided into four groups (n = 6): control group (CG) which received a control diet and water ad libitum; flaxseed group (FG) which received control diet with an addition of 25% flaxseed flour and water ad libitum; ethanol control group (ECG) which received control diet and a solution of 10% ethanol (v/v) as the only liquid source; and ethanol flaxseed group (EFG) which received control diet with an addition of 25% flaxseed flour and a solution of 10% ethanol (v/v) as the only liquid source. The animals were euthanized at 60 days, when blood was collected for biochemical analysis and liver was collected for histomorphometric analysis. Rats fed with diets containing flaxseed showed lower values of alkaline phosphatase (P = 0.020) and lower concentration of total bilirubin (P = 0.006), direct bilirubin (P = 0.013) and indirect bilirubin (P = 0.018) compared to ECG and EFG. The groups receiving flaxseed diets demonstrated higher expression of superoxide dismutase (SOD) enzyme (P < 0.001) than CG and ECG but did not affect thiobarbituric acid (TBARS) expression (P = 0.055). Regarding liver analysis, the ECG and EFG showed larger hepatocyte nuclei and paler cytoplasm than the groups who had not received ethanol, and less in fluid accumulation (oedema) in the cytoplasm than was seen in the FG and EFG livers. These latter two groups showed fewer fatty cells than was seen in the groups that had not been given flaxseed, so that the diagnosis of hepatic steatosis was not justified. In conclusion, therefore, this study showed that the indicators of ethanol chronic consumption can be reduced by the introduction of continuous flaxseed dietary intake.

Addition of pooled pumpkin seed to mixed meals reduced postprandial glycemia: a randomized placebo-controlled clinical trial

We investigated if pumpkin and flaxseeds could improve postprandial glycemic, food intake, and appetitive responses. Herein, we hypothesize based on the literature that pumpkin seed has potential to lower postprandial glycemic effects. Therefore, we conducted a randomized, single-blind, placebo-controlled, crossover design study involving normoglycemic adults (food intake: n = 25; glycemia: n = 15). Three high-carbohydrate mixed meals presenting no seed (control [C]) or 65 g of the tested seeds (pumpkin seed [P] or flaxseed [F]) were consumed in 3 nonconsecutive days. Test meals had similar nutritional composition. Blood glucose was measured by capillary finger blood at 0 (immediately before), 15, 30, 45, 60, 90, and 120 minutes after the ingestion of each meal, and the incremental area under glycemic response curves (iAUC) were calculated. Appetitive responses were assessed, and dietary records were used to evaluate food intake on testing days. Glucose iAUC was significantly lower in P compared with C (reduction of ~35%, P = .025). There was no significant differences in glucose iAUC between F and C (P = .257). Glycemic response at each time point did not differ between C, P, and F (P_{group × time} = .238). Fiber consumption was higher in F (P = .009) than in C, but there were no differences in appetitive responses, energy, or macronutrient consumptions between dietary interventions. Acute consumption of 65 g of pumpkin seed markedly reduced postprandial glycemia. Pumpkin seed has potential as a hypoglycemic food, which now deserves to be confirmed in long-term studies.

Medicinal plants and bioactive natural compounds in the treatment of non-alcoholic fatty liver disease: A clinical review

Non-alcoholic fatty liver disease (NAFLD) is a major cause of liver diseases, and is closely related to metabolic syndrome and its related conditions, diabetes mellitus and dyslipidemia. On the other hand, NAFLD as a multisystem disease increases the risk of several chronic diseases include type 2 diabetes mellitus, cardiovascular disease (CVD), and chronic kidney disease. The main objective was to review the efficacy of bioactive natural compounds assessed by clinical trials. Search literature using four databases (PubMed, EBSCO, Web of Science, and Ovid Medline) to review publications that focused on the impact of bioactive natural compounds in NAFLD treatment. Due to the lack of effective pharmacological treatments available for NAFLD, lifestyle modifications such as following a healthy diet, vigorous physical activity, and weight reduction remain the first line of treatment for NAFLD. However, due to the poor adherence to this type of treatment, especially for long-term weight loss diets some of which may have harmful effects on the liver, finding novel therapeutic agents for NAFLD treatment and/or preventing NAFLD progression has garnered significant interest. Although the therapeutic agents of NAFLD treatment have been reviewed previously, to date, no summary has been conducted of clinical trials examining the effects of herbal compounds on NAFLD-related biomarkers. This review highlights the beneficial role of herbal bioactives and medicinal plants in NAFLD treatment, particularly as complementary to a healthy lifestyle. All natural products described in this review seem to have some benefits to improve oxidative stress, cellular inflammation and insulin-resistance, which always remain as the "primum movens" of NAFLD pathogenesis.

The effect of flaxseed supplementation on body weight and body composition: a systematic review and meta-analysis of 45 randomized placebo-controlled trials

Flaxseed consumption may be inversely associated with obesity; however, findings of available randomized controlled trials (RCTs) are conflicting. The present study aimed to systematically review and analyse RCTs assessing the effects of flaxseed consumption on body weight and body composition. PubMed, Medline via Ovid, SCOPUS, EMBASE and ISI Web of Sciences databases were searched up to November 2016. Mean changes in body composition indices including body weight, body mass index (BMI) and waist circumference were extracted. Effect sizes were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI). Heterogeneity between studies was assessed with the I² test. Publication bias and subgroup analyses were also performed. The quality of articles was assessed via the Jadad scale. A total of 45 RCTs were included. Meta-analyses suggested a significant reduction in body weight (WMD: -0.99 kg, 95% CI: -1.67, -0.31, p = 0.004), BMI (WMD: -0.30 kg m^-2 , 95% CI: -0.53, -0.08, p = 0.008) and waist circumference (WMD: -0.80 cm, 95% CI: -1.40, -0.20, p = 0.008) following flaxseed supplementation. Subgroup analyses showed that using whole flaxseed in doses ≥30 g d^-1 , longer-term interventions (≥12 weeks) and studies including participants with higher BMI (≥ 27 kg m^-2 ) had positive effects on body composition. Whole flaxseed is a good choice for weight management particularly for weight reduction in overweight and obese participants.

Functional implications of maternal intake of flaxseed and its by-products during pregnancy and lactation on offspring

Purpose

The purpose of this review of the literature is to provide data about flaxseed intake during pregnancy and/or lactation and its effects in the offspring from birth to adulthood.

Design/methodology/approach

This review includes up-to-date information from evidence-based sources on flaxseed intake and its by-products, during pregnancy and lactation and its effects on male and female offspring, from post-weaning until adulthood. Topics included are effects on body mass; glycaemic metabolism; lipid profile; blood pressure and aortic structure; reproductive system and brain tissue.

Findings

The main effects of flaxseed or its by-products were observed in the cardiovascular system, where a lipid profile improvement and minor aortic remodelling were noticed, and in the cerebral development, where greater n-3 PUFA incorporation in the brain was detected.

Originality/value

The research done in this study, to understand the offspring response that were early exposed to the flaxseed components during pregnancy and lactation, may be the first step toward guiding future strategies for recommending the use of this seed during the offspring’s perinatal period.

Flaxseed supplementation in non-alcoholic fatty liver disease: a pilot randomized, open labeled, controlled study

A two-arm randomized open labeled controlled clinical trial was conducted on 50 patients with non-alcoholic fatty liver disease (NAFLD). Participants were assigned to take either a lifestyle modification (LM), or LM +30 g/day brown milled flaxseed for 12 weeks. At the end of the study, body weight, liver enzymes, insulin resistance and hepatic fibrosis and steatosis decreased significantly in both groups (p< 0.05); however, this reduction was significantly greater in those who took flaxseed supplementation (p < 0.05). The significant mean differences were reached in hepatic markers between flaxseed and control group, respectively: ALT [-11.12 compared with -3.7 U/L; P< 0.001], AST [-8.29 compared with -4 U/L; p < 0.001], GGT [-15.7 compared with -2.62 U/L; p < 0.001], fibrosis score [-1.26 compared with -0.77 kPa; p = 0.013] and steatosis score [-47 compared with -15.45 dB/m; p = 0.022]. In conclusion, flaxseed supplementation plus lifestyle modification is more effective than lifestyle modification alone for NAFLD management.

Maternal exposure to diets containing flaxseed flour or flaxseed oil during pregnancy and lactation protects the aortic remodeling in adult male offspring of diabetic rat dams

BACKGROUND

Diabetes during pregnancy is associated with cardiovascular complications in the fetus and extends into adulthood. Therapeutic applications of flaxseed have been studied in cardiovascular disorders, because its oilseed is the best plant source of omega-3 fatty acid, which is currently considered by researchers to be an essential protective against cardiovascular disease. The aim of this study was to evaluate the influence of flaxseed flour and oil on cardiovascular biochemical parameters and the histoarchitecture of the aorta in adult rats which were offspring of diabetic mothers.

RESULTS

At 100 days of age in offspring it was observed that maternal consumption of a high-fat diet containing flaxseed oil (FOG) and flaxseed flour (FFG) did not affect the serum concentration of monocyte chemoattractant protein-1, vascular endothelial growth factor, cholesterol, triglycerides, high-density-, low-density- or very-low-density-lipoprotein cholesterol. However, the thickness of the intima media layer of the aorta was significantly smaller in FOG and FFG groups; the lumen area was similar among the groups; and a higher percentage of elastic fiber was found in FOG and FFG groups.

CONCLUSION

These data suggest that the use of both flaxseed flour and its oil reduces the remodeling of the aorta; however; it has not been possible to modify the cardiovascular biochemical parameters.

The effects of a diet formulation with oats, soybeans, and flax on lipid profiles and uricemia in patients with AIDS and dyslipidemia

INTRODUCTION

Although the initiation of highly active antiretroviral therapy (HAART) is accompanied by an attenuation of viral load, metabolic disorders characterized by hyperglycemia, dyslipidemia, and lipodystrophy are often observed in patients under this treatment. Certain foods, such as oat bran, soy protein, and flaxseed, have been shown to improve a patient's lipid profile despite possible increases in uricemia. Thus, a bioactive compound was formulated using these foods to help patients with HIV/AIDS control metabolic disorders resulting from HAART.

METHODS

An uncontrolled before and after study was performed. The total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, and uric acid before and after 3 months of consuming the formulation were compared in patients. The compound was formulated such that 40g (the recommended daily intake) contained approximately 10g of flaxseed, 20g of oat bran, and 10g of textured soy protein.

RESULTS

The study population consisted of 139 patients, 31 of whom were included in the final analysis. There were no significant variations between the laboratory results obtained before and after consumption of the compound.

CONCLUSIONS

The regular consumption of the formulation together with individualized dietary guidance did not reduce lipid levels and did not contribute to an increase in uricemia in the study group. However, new studies with higher doses of the foods that compose the formulation should be encouraged to investigate whether these foods can positively influence the lipid profiles of these patients.

Ponderal behavior of rats fed an omegas 3, 6 and 9 enriched diet submitted to colon carcinogenesis induced by azoxymethane

PURPOSE

To assess weight changes in rats fed diets with different ratios of omegas 3, 6 and 9 submitted to colonic carcinogenesis induced by Azoxymethane (AOM).

METHODS

Sixty rats with three weeks of life were distributed into five groups of specific diets containing 12 animals each: GI- Standard diet without administration of AOM, GII- Standard diet with administration of AOM; GIII- Hyperlipidic diet with administration of AOM; GIV-Normolipidic diet with administration of AOM; GV- Hypolipidic diet with administration of AOM. The weight and food intake of each group were assessed four times in each week throughout the experiment until euthanasia at 36th week.

RESULTS

GI and GII had no significant difference in weight. GI showed a significant increase when compared to GIII, GIV and GV. GII also showed a significant increase when compared to GIII, GIV and GV. When comparing intake of GI as compared to GII no significant difference was found, however such groups had higher intake than groups III, IV and V. There were found no difference in weight when comparing among rats with and without cancer within each groups: GII, GIII, GIV and GV.

CONCLUSIONS

Diets rich in omega 3, 6 and 9 reduced food intake and weight. Rats with colorectal cancer had no decrease in weight as compared to those without this condition in the same group.