Synergistic effect of eicosapentaenoic acid-enriched phospholipids and sea cucumber saponin on orotic acid-induced non-alcoholic fatty liver disease in rats

Nigella sativa L. and its bioactive and nutraceutical components in the management of diabetic peripheral neuropathy

Diabetes-induced hyperglycemia leads to excessive production of oxygen free radicals, inflammatory cytokines, and oxidative stress, which initiates diabetic peripheral neuropathy (DPN). Currently, this condition affects 20% of adults with diabetes. Despite significant advances in the treatment of diabetes, the incidence of its complications, including DPN, is still high. Thus, there is a growing research interest in developing more effective and treatment approaches with less side effects for diabetes and its complications. Nigella sativa L. (NS) has received much research attention as an antioxidant, anti-yperglycemic factor, and anti-inflammatory agent. This natural compound demonstrates its antidiabetic neuropathy effect through various pathways, including the reduction of lipid peroxidation, the enhancement of catalase and superoxide dismutase enzyme activity, and the decrease in inflammatory cytokine levels. The present review focuses on the bioactive and nutraceutical components of black cumin (Nigella sativa L.) and their effects on DPN. In addition, we have also summarized the findings obtained from several experimental and clinical studies regarding the antidiabetic neuropathy effect of NS in animal models and human subjects.

Effect of dietary supplementation with sanguinarine on meat quality and lipid metabolism of broilers

Dietary Macleaya cordata extract (MCE) can improve the meat quality of poultry. However, the specific mechanism by which MCE regulates the meat quality has not been clarified yet. Sanguinarine (SAN) is one of the important natural active components in MCE. Our study aims to explore the regulatory mechanism of dietary SAN supplementation on meat quality through transcriptomic and gut microbiome analysis, thereby providing a basis for regularing meat quality with MCE. 240 1-day-old broilers were divided into 4 groups according to different doses of SAN (0, 0.225, 0.75, and 2.25 mg/kg). The results indicated that SAN significantly improve the physicochemical quality indicators of breast and thigh muscle in broilers, improved the serum biochemical indexes. Through transcriptome sequencing analysis of the liver and ileum tissues of broilers, we found that the differentially expressed genes induced by SAN were mainly enriched in lipid metabolism, which were related to the peroxisome proliferator-activated receptor (PPAR) pathway. It reconfirmed that SAN can regulate lipid metabolism in the body by promoting the expression of genes related to cholesterol metabolism, fatty acid transport and oxidation by RT-PCR, this ultimately affects the physicochemical quality of muscle. Additionally, through 16S rRNA sequencing analysis, we found that dietary addition of SAN increased the relative abundance of Bacteroides, Lactobacillus and unclassified_f_Lachnospiraceae, while decreased the relative abundance of Alistipes in ceca. To further investigate the impact of gut microbiota on lipid metabolism, we conducted a correlation analysis of PPAR pathway factor expression in cecum tissue and microflora structure. The results showed that Bacteroides exhibited a positive correlation with the expression of most genes in the PPAR signaling pathway. Unclassified_f__Lachnospiraceae is positively correlated with PPARγ, Cytochrome P450 family 7 subfamily A member 1 (CYP7A1) and Acyl-CoA synthetase long-chain family member 5 (ACSL5). In conclusion, dietary addition of SAN can promote the genes expression of the PPAR pathway, target the regulation of intestinal microflora structure and abundance and regulate lipid metabolism, thereby improving meat quality of broilers.

Natural products in atherosclerosis therapy by targeting PPARs: a review focusing on lipid metabolism and inflammation

Inflammation and dyslipidemia are critical inducing factors of atherosclerosis. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors and control the expression of multiple genes that are involved in lipid metabolism and inflammatory responses. However, synthesized PPAR agonists exhibit contrary therapeutic effects and various side effects in atherosclerosis therapy. Natural products are structural diversity and have a good safety. Recent studies find that natural herbs and compounds exhibit attractive therapeutic effects on atherosclerosis by alleviating hyperlipidemia and inflammation through modulation of PPARs. Importantly, the preparation of natural products generally causes significantly lower environmental pollution compared to that of synthesized chemical compounds. Therefore, it is interesting to discover novel PPAR modulator and develop alternative strategies for atherosclerosis therapy based on natural herbs and compounds. This article reviews recent findings, mainly from the year of 2020 to present, about the roles of natural herbs and compounds in regulation of PPARs and their therapeutic effects on atherosclerosis. This article provides alternative strategies and theoretical basis for atherosclerosis therapy using natural herbs and compounds by targeting PPARs, and offers valuable information for researchers that are interested in developing novel PPAR modulators.

Eicosapentaenoic acid-enriched phospholipids alleviate glucose and lipid metabolism in spontaneously hypertensive rats with CD36 mutation: a precise nutrition strategy

Previous studies have found that eicosapentaenoic acid-enriched phospholipids (EPA-PLs) alleviated glucose and lipid metabolism, which was accompanied by an increase of cluster of differentiation 36 (CD36). However, the effects of EPA-PLs on glucose and lipid metabolism in the case of CD36 mutation are unclear. Thus, spontaneously hypertensive rats/NCrl (SHR) were used as a CD36 mutation model to determine the effects of dietary 2% EPA-PLs for 4 weeks on glucose and lipid metabolism. The results showed that the intervention of EPA-PLs significantly alleviated the abnormal increase of serum free fatty acid levels and glycerol levels in SHRs. Moreover, the administration of EPA-PLs decreased the triglyceride levels and cholesterol levels by 31.1% and 37.9%, respectively, in the liver. Dietary EPA-PLs had no effect on epididymal fat weight, but EPA-PLs inhibited adipocyte hypertrophy in SHRs. Further mechanistic research found that EPA-PL pretreatment significantly reduced triacylglycerol catabolism and increased fatty acid β-oxidation. Additionally, the administration of EPA-PLs decreased the area under the curve of the intraperitoneal glucose tolerance test and fasting serum insulin levels by activating the IRS/PI3K/AKT signaling pathway. Furthermore, EPA-PL pretreatment significantly increased the CD36 gene expression in the liver tissues, adipose tissues and muscle tissues even in the case of CD36 mutation. These results indicated that EPA-PLs alleviate glucose and lipid metabolism in the case of CD36 mutation, which provides a precise nutrition strategy for people with CD36 mutation.

Combination of marine bioactive compounds and extracts for the prevention and treatment of chronic diseases

Background

In recent years, marine-based functional foods and combination therapy are receiving greater recognition for their roles in healthy lifestyle applications and are being investigated as viable and effective strategies for disease treatment or prevention.

Aim of the review

This review article presents and discusses the relevant scientific publications that have studied the synergistic and additive effects of natural marine bioactive compounds and extract combinations with anti-obesity, anti-inflammatory, antioxidant, and chemopreventive activities in the last two decades. The paper presents the mechanism of action and health benefits of developed combinations and discusses the limitation of the studies. Furthermore, it recommends alternatives and directions for future studies. Finally, it highlights the factors for developing novel combinations of marine bioactive compounds.

Key scientific concepts of review

Combination of marine bioactive compounds or extracts affords synergistic or additive effects by multiple means, such as multi-target effects, enhancing the bioavailability, boosting the bioactivity, and neutralizing adverse effects of compounds in the mixture. For the development of marine-based combinations, there are key points for consideration and issues to address: knowledge of the mechanism of action of individual compounds and their combinations, optimum ratio and dosing of compounds, and experimental models must all be taken into account. Strategies to increase the number and diversity of marine combinations, and further development of marine-based functional foods, are available. However, only a small number of natural marine bioactive combinations have been assessed, and most research has been focused on fish oil and carotenoid synergy. Therefore, more research and resources should be spent on developing novel marine bioactive combinations as functional foods and nutraceuticals.

Sea cucumber-derived compounds for treatment of dyslipidemia: A review

Dyslipidemias are disorders of plasma levels of lipids, such as elevated levels of total cholesterol and triglyceride, that are associated with various human diseases including cardiovascular disease (CVD) and non-alcoholic fatty liver disease (NAFLD). Statins are the first-line drugs for treatment of dyslipidemia. However, a substantial proportion of patients cannot reach the recommended LDL-c level even with the highest tolerated doses of statins, and there is no available drug specifically for NAFLD therapy. Sea cucumbers are one of the widely distributed invertebrates, and are an important resource of food and medicine. Sea cucumbers have many valuable nutrients including saponins, fatty acids, phospholipids, cerebrosides, sulfated polysaccharides, as well as proteins and peptides. In recent years, these natural products derived from sea cucumbers have attracted attentions for treatment of CVD and NAFLD because of their lipid-lowering effect and low toxicity. However, the hypolipidemic mechanisms of action and the structure-activity relationship of these bioactive components have not been well-documented in literature. This review article summarizes the signaling pathways and the potential structure-activity relationship of sea cucumber-derived bioactive compounds including saponins, lipids, carbohydrates as well as peptides and proteins. This article will provide information useful for the development of sea cucumber-derived lipid-lowering compounds as well as for investigation of hypolipidemic compounds that are derived from other natural resources.

Astragalus polysaccharide mitigates transport stress-induced hepatic metabolic stress via improving hepatic glucolipid metabolism in chicks

In the modern poultry industry, newly hatched chicks are unavoidably transported from the hatching to the rearing foster. Stress caused by multiple physical and psychological stressors during transportation is particularly harmful to the liver. Astragalus polysaccharide (APS) possesses multiple benefits against hepatic metabolic disorders. Given that transport stress could disturb hepatic glucolipid metabolism and the role of APS in metabolic regulation, we speculated that APS could antagonize transport stress-induced disorder of hepatic glucolipid metabolism. Firstly, newly hatched chicks were transported for 0, 2, 4, 8 h, respectively. Subsequently, to further investigated the effects of APS on transport stress-induced hepatic glucolipid metabolism disturbance, chicks were pretreated with water or APS and then subjected to transport treatment. Our study suggested that APS could relieve transport stress induced lipid deposition in liver. Meanwhile, transport stress also induced disturbances in glucose metabolism, reflected by augmented mRNA expression of key molecules in gluconeogenesis and glycogenolysis. Surprisingly, APS could simultaneously alleviate these alterations via PGC1α/SIRT1/AMPK pathway. Moreover, APS treatment regulated the level of PPARα and PPARγ, thereby alleviating transport stress-induced alterations of VLDL synthesis, cholesterol metabolism, lipid oxidation, synthesis and transport-related molecules. These findings indicated that APS could prevent the potential against transport stress-induced hepatic glucolipid metabolism disorders via PGC1α/ SIRT1/ AMPK/ PPARα/ PPARγ signaling system.

The Possible Role of Saponin in Type-II Diabetes- A Review

BACKGROUND

The possible role of secondary metabolites in the management of diabetes is a great concern and constant discussion. This characteristic seems relevant and should be the subject of thorough discussion with respect to saponin.

OBJECTIVE

The current data mainly focus on the impact of saponin in the treatment of type-II diabetes. The majority of studies emphasize on other secondary metabolites such as alkaloids and flavonoids, but very few papers are there representing the possible role of saponin as these papers express the narrow perspective of saponin phytoconstituents but lacking in providing the complete information on various saponin plants. The aim of the study was to summarize all available data concerning the saponin containing plant in the management of type-II diabetes.

METHODS

All relevant papers on saponin were selected. This review summarizes the saponin isolation method, mechanism of action, clinical significance, medicinal plants and phytoconstituents responsible for producing a therapeutic effect in the management of diabetes.

RESULTS

The saponin is of high potential with structural diversity and inhibits diabetic complications along with reducing the hyperglycemia through different mechanisms thereby providing scope for improving the existing therapy and developing the novel medicinal agents for curing diabetes.

CONCLUSION

Saponins having potential therapeutic benefits and are theorized as an alternative medication in decreasing serum blood glucose levels in the patient suffering from diabetes.

Knockdown of phosphatase and tensin homolog (PTEN) inhibits fatty acid oxidation and reduces very low density lipoprotein assembly and secretion in calf hepatocytes

Dairy cows with fatty liver exhibit hepatic lipid accumulation and disturbances in fatty acid oxidation and lipid transport. Phosphatase and tensin homolog (PTEN), a lipid phosphatase, regulates intrahepatic fatty acid oxidation and lipid transport in mice. Whether PTEN play a role in fatty acid oxidation and very low density lipoprotein (VLDL) assembly in calf hepatocytes are unknown. Hepatocytes isolated from 3 healthy female Holstein calves (1 d old, 30-40 kg) were infected with empty adenovirus with green fluorescent protein for 48 h (Ad-GFP group) or infected with PTEN knockdown adenovirus for 48 h (Ad-shPTEN group), or cultured in RPMI-1640 without Ad-shPTEN or Ad-GFP (control group). Compared with the Ad-GFP group, PTEN knockdown decreased mRNA and protein abundance and the activity of fatty acid oxidation-related molecules, including acyl-coA synthetase long-chain 1, carnitine palmitoyltransferase 1, carnitine palmitoyltransferase 2, and 3-hydroxy acyl-coA dehydrogenase. Furthermore, PTEN knockdown decreased mRNA and protein abundance of VLDL assembly-related molecules, including apolipoprotein B100, apolipoprotein E, microsomal triglyceride transfer protein, and low density lipoprotein receptor. Importantly, PTEN knockdown promoted triglyceride accumulation in hepatocytes and reduced the VLDL content in culture medium. A subsequent study was conducted on the following 4 groups: cells infected with Ad-GFP for 48 h and then treated with 2% BSA for another 24 h (Ad-GFP + BSA); cells infected with Ad-GFP for 48 h and then treated with 1.2 mM free fatty acids (FFA) and 2% BSA for another 24 h (Ad-GFP + 1.2 mM FFA); cells infected with Ad-shPTEN for 48 h and then treated with 2% BSA for another 24 h (Ad-shPTEN + BSA); cells infected with Ad-shPTEN for 48 h and then treated with 1.2 mM FFA and 2% BSA for another 24 h (Ad-shPTEN + 1.2 mM FFA). Compared with Ad-GFP + BSA, the abundances of PTEN and of fatty acid oxidation- and VLDL assembly-related proteins were lower in the Ad-GFP + 1.2 mM FFA group. Importantly, PTEN knockdown heightened the increase in triglyceride accumulation of hepatocytes and the decrease in VLDL content in culture medium induced by FFA. Overall, these in vitro data indicate that FFA inhibits PTEN expression, leading to triglyceride accumulation and the inhibition of VLDL assembly in calf hepatocytes. These findings suggest that PTEN may be a potential therapeutic target for FFA-induced hepatic steatosis in dairy cows.

Relationship between structure and efficacy of sea cucumber saponins echinoside A and its derivatives on hemolytic activity and prevention of nonalcoholic fatty liver disease

The hemolytic property discourages the development of sea cucumber saponins on alleviating lipids metabolism disturbance. The hemolytic activity of saponins has been reported to be highly correlative to their chemical structures. The aim of this study was to reduce the hemolytic activity of sea cucumber-derived saponins echinoside A (EA) and simultaneously remain its effect on alleviating non-alcoholic fatty liver disease (NAFLD) by structural modifications. Administration with EA and its derivatives for 8 weeks remarkably mitigated orotic acid-induced NAFLD via inhibiting the activities and mRNA expressions of enzymes involved in lipogenesis, enhancing the activities and expressions of enzymes related to hepatic lipolysis in a rat model. Importantly, aglycone exhibited a distinct advantage in stimulating hepatic lipolysis compared with EA and dsEA, meanwhile possessed lowest hemolytic activity. This study may provide the theoretical basis to strengthen the application of sea cucumber saponins as food supplements and/or functional ingredients.

Characterization and Absorption Kinetics of a Novel Multifunctional Nanoliposome Stabilized by Sea Cucumber Saponins Instead of Cholesterol

Cholesterol was usually used to stabilize liposome, although there have been controversies on the relationship between dietary cholesterol and health. The present study aimed to prepare a novel multifunctional nanoliposomes stabilized by sea cucumber-derived saponins using ultrasound-assisted film dispersion method. A novel uniform liposome with a mass ratio of egg yolk lecithin/sea cucumber saponins at 75:25 was successfully prepared to encapsulate saponin, and the particle size was 164.8 ± 1.70 nm with a PDI value of 0.214 ± 0.022 and zeta potential of -15.97 ± 1.23 mV. The digestion and absorption results in vivo showed that the dietary saponins in liposome form could delay the peak time of saponins and prolong their residence time in the serum. Moreover, saponins were more easily converted into their corresponding metabolites after administration with saponins in the liposome form. The novel liposome as an efficient carrier with multiple functions had great potential in the development of functional food and biomedical applications.

Synergistic effect of sea cucumber saponins and EPA-enriched phospholipids on insulin resistance in high-fat diet-induced obese mice

Sea cucumber saponins (SCS) exhibit a significant effect on ameliorating glucose and lipid disorders by inhibiting fatty acid biosynthesis; however, high cytotoxicity and hemolytic activity limit their application. Eicosapentaenoic acid-enriched phospholipids (EPA-PL) significantly ameliorate insulin resistance and elevate the level of hepatic lipolysis, which may have a synergistic effect with SCS in alleviating obesity-related insulin resistance via multiple mechanisms. In the present study, high-fat diet-induced male C57BL/6J mice with obesity-related insulin resistance were used to evaluate the synergistic effect of SCS and EPA-PL on alleviating the insulin resistance. Results show that the combination of SCS and EPA-PL at a half dose exhibited a significant improvement on glucose intolerance and systematic insulin sensitivity than SCS or EPA-PL alone. Moreover, the half dose-combination remarkably inhibited the macrophage infiltration (F4/80) to white adipose tissue (WAT) and significantly down-regulated the level of MCP1, TNF-α and IL-6 compared with SCS and EPA-PL alone. Consequently, the combined administration not only decreased hepatic gluconeogenesis and increased hepatic glycogen synthesis (P < 0.05), but also stimulated the glucose uptake in WAT and muscle (P < 0.05). Nevertheless, neither SCS or EPA-PL alone exhibited any effect on the glucose uptake. The combination of SCS and EPA-PL contributed to a synergistic effect on alleviating the obesity-related insulin resistance due to the amelioration of an inflammation-centric peripheral insulin response.

Marine omega-3 (n-3) phospholipids: A comprehensive review of their properties, sources, bioavailability, and relation to brain health

For several decades, there has been considerable interest in marine-derived long chain n-3 fatty acids (n-3 LCPUFAs) due to their outstanding health benefits. n-3 LCPUFAs can be found in nature either in triglycerides (TAGs) or in phospholipid (PL) form. From brain health point of view, PL n-3 is more bioavailable and potent compared to n-3 in TAG form, as only PL n-3 is able to cross the blood-brain barrier and can be involved in brain biochemical reactions. However, PL n-3 has been ignored in the fish oil industry and frequently removed as an impurity during degumming processes. As a result, PL products derived from marine sources are very limited compared to TAG products. Commercially, PLs are being used in pharmaceutical industries as drug carriers, in food manufacturing as emulsifiers and in cosmetic industries as skin care agents, but most of the PLs used in these applications are produced from vegetable sources that contain less (without EPA, DPA, and DHA) or sometimes no n-3 LCPUFAs. This review provides a comprehensive account of the properties, structures, and major sources of marine PLs, and provides focussed discussion of their relationship to brain health. Epidemiological, laboratory, and clinical studies on n-3 LCPUFAs enriched PLs using different model systems in relation to brain and mental health that have been published over the past few years are discussed in detail.

Cytotoxic Potential of the Coelomic Fluid Extracted from the Sea Cucumber Holothuria tubulosa against Triple-Negative MDA-MB231 Breast Cancer Cells

Growing evidence has demonstrated that the extracts of different holothurian species exert beneficial effects on human health. Triple negative breast cancers (TNBC) are highly malignant tumors that present a poor prognosis due to the lack of effective targeted therapies. In the attempt to identify novel compounds that might counteract TNBC cell growth, we studied the effect of the exposure of the TNBC cell line MDA-MB231 to total and filtered aqueous extracts of the coelomic fluid obtained from the sea cucumber Holoturia tubulosa, a widespread species in the Mediterranean Sea. In particular, we examined cell viability and proliferative behaviour, cell cycle distribution, apoptosis, autophagy, and mitochondrial metabolic/cell redox state. The results obtained indicate that both total and fractionated extracts are potent inhibitors of TNBC cell viability and growth, acting through both an impairment of cell cycle progression and mitochondrial transmembrane potential and a stimulation of cellular autophagy, as demonstrated by the increase of the acidic vesicular organelles and of the intracellular protein markers beclin-1, and total LC3 and LC3-II upon early exposure to the preparations. Identification of the water-soluble bioactive component(s) present in the extract merit further investigation aiming to develop novel prevention and/or treatment agents efficacious against highly metastatic breast carcinomas.