lignans and Dyslipidemias

Flaxseed (Linum usitatissimum) is an oil-based seed that contains high amounts of alpha-linolenic acid, linoleic acid, lignans, fiber and many other bioactive components which is suggested for a healthier life. Nowadays, flaxseed is known as a remarkable functional food with different health benefits for humans and protects against cardiovascular disease, diabetes, dyslipidemia, obesity and altogether metabolic syndrome.. To review the bioactive components of flaxseed and their potential health effects, PubMed and Scopus were searched from commencement to July 2019. Keywords including: "flaxseed", "Linum usitatissimum", "metabolic syndrome", "obesity", "inflammation", "insulin resistance", "diabetes", "hyperlipidemia" and "menopause" were searched in the databases with varying combinations.. Consumption of flaxseed in different forms has valuable effects and protects against cardiovascular disease, hypertension, diabetes, dyslipidemia, inflammation and some other complications. Flaxseed can serve as a promising candidate for the management of metabolic syndrome to control blood lipid levels, fasting blood sugar, insulin resistance, body weight, waist circumference, body mass and blood pressure.

Topics: alpha-Linolenic Acid; Blood Glucose; Body Weight; Cardiovascular Diseases; Diabetes Mellitus; Dietary Fiber; Drug Discovery; Dyslipidemias; Flax; Humans; Inflammation; Insulin Resistance; Lignans; Lipids; Metabolic Syndrome; Obesity; Plant Extracts; Seeds

The clinical impact of the fibrate and thiazolidinedione drugs on dyslipidemia and diabetes is driven mainly through activation of two transcription factors, peroxisome proliferator-activated receptors (PPAR)-α and PPAR-γ. However, substantial differences exist in the therapeutic and side-effect profiles of specific drugs. This has been attributed primarily to the complexity of drug-target complexes that involve many coregulatory proteins in the context of specific target gene promoters. Recent data have revealed that some PPAR ligands interact with other non-PPAR targets. Here we review concepts used to develop new agents that preferentially modulate transcriptional complex assembly, target more than one PPAR receptor simultaneously, or act as partial agonists. We highlight newly described on-target mechanisms of PPAR regulation including phosphorylation and nongenomic regulation. We briefly describe the recently discovered non-PPAR protein targets of thiazolidinediones, mitoNEET, and mTOT. Finally, we summarize the contributions of on- and off-target actions to select therapeutic and side effects of PPAR ligands including insulin sensitivity, cardiovascular actions, inflammation, and carcinogenicity.

Topics: Animals; Diabetes Mellitus, Type 2; Dyslipidemias; Humans; Hypoglycemic Agents; Lignans; Peroxisome Proliferator-Activated Receptors; Thiazolidinediones

Type 2 diabetes, a global health concern has been considered as major risk factor for cardiovascular diseases. Hinokinin, an emerging bioactive lignin, is reported to show wide range of pharmacological activities. However, the protective role and mechanisms of Hinokinin against type 2 diabetes-mediated cardiotoxicity are still remains unknown. An experimental type 2 diabetic mice model was created by treating animals with high fat diet for four weeks and intraperitoneal injection of streptozotocin (35 mg/kg body weight). Post-type 2 diabetic induction, animals orally treated with Hinokinin (20 or 40 mg/kg body weight) for six weeks. The type 2 diabetic mice exhibited a rise in blood glucose level as well as glycated hemoglobin (HbA1c %), decrease in weekly body weights, decrease in food intake, reduction in absolute heart weight, fall in serum insulin level with altered lipid profile and cardiac functional damage. Diabetic mice treated with Hinokinin attenuated hyperglycemia, dyslipidemia and cardiac dysfunction. In addition, Hinokinin ameliorated histological alterations, fibrosis and glycated proteins in HFD/STZ-induced mice. Type 2 diabetic condition in mice exacerbated oxidative stress, inflammatory status and apoptosis. Hinokinin treatment significantly assuaged oxidative stress, inflammation and apoptosis and elevated antioxidant defenses in diabetic heart. The underlying mechanisms for such mitigation involved the modulation of Nrf2/Keap1/ARE pathway, MAPKs (JNK, p38 and ERK 1/2) and TLR4/MyD88/NF-κB mediated inflammatory pathways and mitochondrial-dependent (intrinsic) apoptosis pathway. In conclusion, the results of this study provided clear evidence that Hinokinin protects against HFD/STZ (type 2 diabetes)-induced cardiac injury by alleviating oxidative stress, inflammation and apoptosis.

Topics: 4-Butyrolactone; Animals; Anti-Inflammatory Agents; Antioxidants; Apoptosis; Benzodioxoles; Blood Glucose; Cytokines; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Diabetic Cardiomyopathies; Diet, High-Fat; Dyslipidemias; Hyperglycemia; Lignans; Mice; Oxidative Stress; Signal Transduction; Streptozocin

Menopausal women are susceptible to have high risk of cardiovascular diseases, type II diabetes and osteoporosis due to the metabolic disorder caused by estrogen deficiency. Accumulating evidence supports that gut microbiota is a key regulator of metabolic diseases. Our previous metabolomics study interestingly demonstrated that the anti-osteoporotic effects of lignan-rich fraction (SWCA) from Sambucus wialliamsii Hance were related to the restoration of a series of lipid and glucose metabolites. This study aims to investigate how SWCA modulates lipid and glucose metabolism and the underlying mechanism. Our results show that oral administration of SWCA (140 mg/kg and 280 mg/kg) for 10 weeks alleviated dyslipidemia, improved liver functions, prevented glucose tolerance and insulin actions, attenuated system inflammation and improved intestinal barrier in OVX rats. It also induced a high abundance of Actinobacteria, and restored microbial composition. We are the first to report the protective effects of the lignan-rich fraction from S. williamsii on dyslipidemia and insulin resistance. Our findings provide strong evidence for the application of this lignan-rich fraction to treat menopausal lipid disorder and insulin resistance-related diseases.

Topics: Administration, Oral; Animals; Cytokines; Dyslipidemias; Female; Gastrointestinal Microbiome; Glucose; Glucose Tolerance Test; Hypolipidemic Agents; Insulin Resistance; Lignans; Liver; Ovariectomy; Plant Extracts; Plant Stems; Rats; Rats, Sprague-Dawley; Sambucus

The study explored the protective effect of sesamin against lipid-induced renal injury and hyperlipidemia in a rat model. An animal model of hyperlipidemia was established in Sprague-Dawley rats. Fifty-five adult Sprague-Dawley rats were divided into five groups. The control group was fed a standard diet, while the other four groups were fed a high-fat diet for 5 weeks to induce hyperlipidemia. Three groups received oral sesamin in doses of 40, 80, or 160 mg/(kg·day). Seven weeks later, the blood lipids, renal function, antioxidant enzyme activities, and hyperoxide levels in kidney tissues were measured. The renal pathological changes and expression levels of collagen type IV (Col-IV) and α-smooth muscle actin (α-SMA) were analyzed. The administration of sesamin improved the serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, apolipoprotein-B, oxidized-low-density lipoprotein, and serum creatinine levels in hyperlipidemic rats, while it increased the high-density lipoprotein cholesterol and apolipoprotein-A levels. Sesamin reduced the excretion of 24-h urinary protein and urinary albumin and downregulated α-SMA and Col-IV expression. Moreover, sesamin ameliorated the superoxide dismutase activity and reduced malondialdehyde levels in kidney tissue. Sesamin could mediate lipid metabolism and ameliorate renal injury caused by lipid metabolism disorders in a rat model of hyperlipidemia.

Topics: Actins; Animals; Collagen Type IV; Diet, High-Fat; Dietary Fats; Dioxoles; Dose-Response Relationship, Drug; Dyslipidemias; Gene Expression Regulation; Kidney Diseases; Lignans; Molecular Structure; Oxidative Stress; Rats; Rats, Sprague-Dawley

Nonalcoholic fatty liver disease (NAFLD) is defined by a nonalcohol relevant pathological accumulation of fat in the liver. Previous studies have shown that sesamin exerts antioxidant effects and improves lipid metabolism of the fatty liver. In this study, we hypothesized that sesamin improves lipid homeostasis of Sprague-Dawley rats fed a high-fat diet (HFD) by regulating the expression of genes related to de novo lipogenesis and β-oxidation. We induced NAFLD in rats with HFD and examined the effect of sesamin in vivo. The results showed that HFD rats accumulated total cholesterol and triacylglycerols in the liver and developed inflammation, as evidenced by the elevation of interleukin-6 and tumor necrosis factor-α in the liver and serum. Sesamin attenuated the disease progression by improving the blood lipid profile in a dose-dependent manner. Sesamin reduced the serum levels of total cholesterol, triacylglycerols, low-density lipoprotein cholesterol, and free fatty acid, whereas it increased the level of high-density lipoprotein cholesterol. Meanwhile, sesamin increased the activities of hepatic glutathione peroxidase and superoxide dismutase while reducing the level of malonaldehyde and cytochrome P450 2E1. Furthermore, higher doses of sesamin reduced the expression of liver X receptor α and its downstream target genes, whereas it upregulated the peroxisome proliferator-activated receptor α-mediated signaling. These findings suggest that sesamin attenuates diet-induced dyslipidemia and inflammation of NAFLD in rats via mechanisms regulated by liver X receptor α and peroxisome proliferator-activated receptor α.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Cytochrome P-450 CYP2E1; Diet, High-Fat; Dioxoles; Dyslipidemias; Hypolipidemic Agents; Inflammation; Interleukin-6; Lignans; Lipid Metabolism; Lipids; Lipogenesis; Liver; Liver X Receptors; Male; Non-alcoholic Fatty Liver Disease; Oxidative Stress; Phytotherapy; Plant Extracts; PPAR alpha; Rats, Sprague-Dawley; Sesamum; Tumor Necrosis Factor-alpha

Hepatic lipid accumulation is a major risk factor for dyslipidemia, nonalcoholic fatty liver disease, and insulin resistance. The present study was conducted to evaluate hypolipidemic effects of meso-dihydroguaiaretic acid (MDA), anti-oxidative and anti-inflammatory compound isolated from the Myristica fragrans HOUTT., by oil red O staining, reverse transcription-polymerase chain reaction (RT-PCR), and Western blot. MDA significantly inhibited insulin-induced hepatic lipid accumulation in a dose-dependent manner. The lipid-lowering effect of MDA was accompanied by increased expression of proteins involved in fatty acid oxidation and decreased expression of lipid synthetic proteins. In addition, MDA activated AMP-activated protein kinase (AMPK) as determined by phosphorylation of acetyl-CoA carboxylase (ACC), a downstream target of AMPK. The effects of MDA on lipogenic protein expression were suppressed by pretreatment with compound C, an AMPK inhibitor. Taken together, these findings show that MDA inhibits insulin-induced lipid accumulation in human HepG2 cells by suppressing expression of lipogenic proteins through AMPK signaling, suggesting a potent lipid-lowering agent.

Topics: Acetyl-CoA Carboxylase; AMP-Activated Protein Kinases; Cell Culture Techniques; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Dyslipidemias; Enzyme Activation; Enzyme Inhibitors; Fatty Liver; Guaiacol; Hep G2 Cells; Humans; Hypolipidemic Agents; Insulin Resistance; Lignans; Lipid Metabolism; Liver; Molecular Targeted Therapy; Myristica; Non-alcoholic Fatty Liver Disease; Phosphorylation; Phytotherapy; Plant Extracts; Pyrazoles; Pyrimidines