Evaluation of hypolipidemic effects of peanut skin-derived polyphenols in rats on Western-diet

Corrigendum to Peanut (Arachis hypogaea L.) seeds and by-products in metabolic syndrome and cardiovascular disorders: A systematic review of clinical studies Phytomedicine 123 (2024) 155170

BACKGROUND

Cardiovascular diseases (CVDs) are the leading causes of death worldwide. The main risk factors are hypertension, diabetes, obesity, and increased serum lipids. The peanut (Arachis hypogaea L.), also known as the groundnut, goober, pindar, or monkey nut, belongs to the Fabaceae family and is the fourth most cultivated oilseed in the world. The seeds and skin of peanuts possess a rich phytochemical profile composed of antioxidants, such as phenolic acids, stilbenes, flavonoids, and phytosterols. Peanut consumption can provide numerous health benefits, such as anti-obesity, antidiabetic, antihypertensive, and hypolipidemic effects. Accordingly, peanuts have the potential to treat CVD and counteract its risk factors.

PURPOSE

This study aims to critically evaluate the effects of peanuts on metabolic syndrome (MetS) and CVD risk factors based on clinical studies.

METHOD

This review includes studies indexed in MEDLINE-PubMed, COCHRANE, and EMBASE, and the Preferred Reporting Items for a Systematic Review and Meta-Analysis guidelines were adhered to.

RESULTS

Nineteen studies were included and indicated that the consumption of raw peanuts or differing forms of processed foods containing peanut products and phytochemicals could improve metabolic parameters, such as glycemia, insulinemia, glycated hemoglobin, lipids, body mass index, waist circumference, atherogenic indices, and endothelial function.

CONCLUSION

We propose that this legume and its products be used as a sustainable and low-cost alternative for the prevention and treatment of MetS and CVD. However, further research with larger sample sizes, longer intervention durations, and more diverse populations is needed to understand the full benefit of peanut consumption in MetS and CVD.

Bioactive compounds of peanut skin in prevention and adjunctive treatment of chronic non-communicable diseases

The global prevalence of cancer continues to increase, so does its mortality. Strategies that can prevent/treat this condition are therefore required, especially low-cost and low-toxicity strategies. Bioactive compounds of plant origin have been presented as a good alternative. In this scenario, due to its abundant polyphenolic content (around 60 to 120 times greater than that of the grain), peanut skin by-products stand out as a sustainable source of food bioactives beneficial to human health. Investigated studies highlighted the importance of peanut skin for human health, its phytochemical composition, bioactivity and the potential for prevention and/or adjuvant therapy in cancer, through the advanced search for articles in the Virtual Health Library (VHL), Science direct and the Mourisco platform of the FioCruz Institute, from 2012 to 2022. Using the keywords, "peanut skin" AND "cancer" AND NOT "allergy", the words "peanut testa" and "peanut peel" were included replacing "peanut skin". 18 articles were selected from Plataforma Mourisco, 26 from Science Direct and 26 from VHL. Of these, 7 articles evaluated aspects of cancer prevention and/or treatment. Promising benefits were found in the prevention/treatment of chronic non-communicable diseases in the use of peanut and peanut skin extracts, such as cholesterolemia and glucose control, attenuation of oxidative stress and suppressive action on the proliferation and metabolism of cancer cells.

Peanut (Arachis hypogaea L.) seeds and by-products in metabolic syndrome and cardiovascular disorders: A systematic review of clinical studies

BACKGROUND

Cardiovascular disease (CVDs) is the leading cause of death worldwide. The main risk factors are hypertension, diabetes, obesity, and increased serum lipids. The peanut (Arachis hypogaea L.), also known as the groundnut, goober, pindar, or monkey nut, belongs to the Fabaceae family and is the fourth most cultivated oilseed in the world. The seeds and skin of peanuts possess a rich phytochemical profile composed of antioxidants, such as phenolic acids, stilbenes, flavonoids, and phytosterols. Peanut consumption can provide numerous health benefits, such as anti-obesity, antidiabetic, antihypertensive, and hypolipidemic effects. Accordingly, peanuts have the potential to treat CVD and counteract its risk factors.

PURPOSE

This study aims to critically evaluate the effects of peanuts on metabolic syndrome (MetS) and CVD risk factors based on clinical studies.

METHOD

This review includes studies indexed in MEDLINE-PubMed, COCHRANE, and EMBASE, and the Preferred Reporting Items for a Systematic Review and Meta-Analysis guidelines were adhered to.

RESULTS

Nineteen studies were included and indicated that the consumption of raw peanuts or differing forms of processed foods containing peanut products and phytochemicals could improve metabolic parameters, such as glycemia, insulinemia, glycated hemoglobin, lipids, body mass index, waist circumference, atherogenic indices, and endothelial function.

CONCLUSION

We propose that this legume and its products be used as a sustainable and low-cost alternative for the prevention and treatment of MetS and CVD. However, further research with larger sample sizes, longer intervention durations, and more diverse populations is needed to understand the full benefit of peanut consumption in MetS and CVD.

Identification of peanut skin components for treating hepatocellular carcinoma via network pharmacology and in vitro experiments

Peanut skin (PS) contains various flavonoids and phenols that have antitumor and antioxidant effects. However, no research has been conducted on PS and hepatocellular carcinoma (HCC). Therefore, this study sought to explore the potential mechanism of PS in treating HCC. PS was searched for in the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform and SYMMAP databases. HCC targets were searched for in five major databases. Protein-protein interaction network, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes analyses were performed. Molecular docking and molecular dynamics simulation were used for verification. Furthermore, in vitro experiments were used to verify the regulation of PS on human HCC (HepG2) cells. Ten ingredients and 95 common targets were identified for PS and HCC, respectively. The key targets of ingredients mainly relate to pathways such as hepatitis B, lipid and atherosclerosis, advanced glycation end products (AGEs)-AGE receptors (RAGEs) signaling pathway in diabetic complications, interleukin-17 (IL-17) signaling pathway, mitogen activated kinase-like protein (MAPK) signaling pathway, the PI3K-Akt signaling pathway. In addition, the molecular docking and molecular dynamics simulation analysis indicated the ingredients had strong binding ability with the targets. Moreover, in vitro experiments confirmed that luteolin can promote the apoptosis of HepG2 cells by controlling the expression of phosphorylated protein-tyrosine kinase (p-AKT). This study provides preliminary evidence that PS produces a marked effect in regulating multiple signaling pathways in HCC through multiple ingredients acting on multiple core genes, including AKT serine/threonine kinase 1 (AKT1), MYC, caspase 3 (CASP3), estrogen receptor 1 (ESR1), epidermal growth factor receptor (EGFR), jun proto-oncogene(JUN), and provides the basis for follow-up research to verify the mechanism of action of PS in treating HCC.

Mechanisms of action of natural products on type 2 diabetes

Over the past several decades, type 2 diabetes mellitus (T2DM) has been considered a global public health concern. Currently, various therapeutic modalities are available for T2DM management, including dietary modifications, moderate exercise, and use of hypoglycemic agents and lipid-lowering medications. Although the curative effect of most drugs on T2DM is significant, they also exert some adverse side effects. Biologically active substances found in natural medicines are important for T2DM treatment. Several recent studies have reported that active ingredients derived from traditional medicines or foods exert a therapeutic effect on T2DM. This review compiled important articles regarding the therapeutic effects of natural products and their active ingredients on islet β cell function, adipose tissue inflammation, and insulin resistance. Additionally, this review provided an in-depth understanding of the multiple regulatory effects on different targets and signaling pathways of natural medicines in the treatment of T2DM as well as a theoretical basis for clinical effective application.

Dietary polyphenols maintain homeostasis via regulating bile acid metabolism: a review of possible mechanisms

The synthesis and metabolism of bile acids (BAs) have been implicated in various metabolic diseases, including obesity and diabetes. Dietary polyphenols, as natural antioxidants, play a vital role in synthesizing and metabolizing bile acids. This paper reviews the mechanism of dietary polyphenols involved in bile acid (BA) synthesis and metabolism. The impact of different gut microorganisms on BA profiles is discussed in detail. The regulation of BA metabolism by dietary polyphenols can be divided into two modes: (1) dietary polyphenols directly activate/inhibit farnesol X receptor (FXR) and Takeda G protein-coupled receptor (TGR5); (2) dietary polyphenols regulate BA synthesis and metabolism through changes in intestinal microorganisms. Research on direct activation/inhibition of FXR and TGR5 by polyphenols should be ramped up. In addition, the effect of dietary polyphenols on intestinal microorganisms has been paid more and more attention and has become a target that cannot be ignored.

Protective effects of peanut skin extract on high-fat and high-fructose diet-induced kidney injury in rats

Chronic kidney disease (CKD) is becoming a major public health problem worldwide. This study aimed to explore whether peanut skin extract (PSE) has protective effects against high-fat and high-fructose (HF) diet-induced kidney injury. Rats were fed HF diet in the whole experiment, while rats in PSE-treated groups were supplemented with PSE. Finally, PSE reduced kidney tissue weight, perinephric fat weight, and levels of serum ammonia, creatinine, and urea nitrogen, along with decreases of renal IL-1β and TNF-α level. Histological examination indicated that PSE alleviated renal tubular dilatation, and degeneration and partial exfoliation of renal tubular epithelial cells. In addition, PSE decreased serum and urinary uric acid level, together with reductions of XOD production and XOD activity both in serum and liver, and down-regulated expressions of renal NLRP3 and ERS proteins. Thus, PSE may be a potential functional food for protecting against renal injury in high energy intake.

In vitro antioxidant, anti-glycation, and bile acid-lowering capacity of peanut milk fermented with Lactiplantibacillus plantarum Kinko-SU4

Plant-based milk-like products from soybeans and other legumes and nuts have been explored worldwide, owing to their nutritional and functional characteristics. This study was conducted to develop new functional food materials from peanut (Arachis hypogaea) milk (PM) with desirable health functions to mitigate lifestyle and age-related diseases. The antioxidant, anti-glycation and bile acid-lowering properties of PM fermented with lactic acid bacteria Lactiplantibacillus plantarum Kinko-SU4 (FPM) were determined in vitro. L. plantarum Kinko-SU4 lowered the pH level from 6.4 to 4.3, 3.9, and 3.7 at 10, 24, and 48 h, respectively. The lactic acid concentration was 4.4 mg/mL after 48 h of incubation. The starter degraded the dissolved proteins in PM, including Ara h 1, one of the peanut allergens. Although the total phenolic content was 36% lower in FPM than in unfermented PM, O2 - radical-scavenging capacity was high in FPM. Anti-glycation in a bovine serum albumin-fructose model and the bile acid-lowering capacities of PM were distinctly increased following fermentation. The result of this study infers that PM fermented with L. plantarum Kinko-SU4 can be considered a desirable food material to prevent and ameliorate chronic lifestyle diseases, particularly in the elderly.

Effects of whole peanut within an energy-restricted diet on inflammatory and oxidative processes in obese women: a randomized controlled trial

BACKGROUND

Peanut consumption has little effect on body weight, despite its high energy density and is associated with reduced cardiovascular disease risk. Based on previous research, we hypothesized that the consumption of whole peanut would be associated with greater improvements in body composition, lipid profile, and biomarkers of inflammation and oxidative stress.

METHODOLOGY

Twenty-four women with obesity [body mass index (BMI) > 30 kg m^-2 ], 33.1 ± 8.7 years old, were assigned to three groups and consumed 56 g of whole peanut (WP), skinned peanut (SP), and no peanut (NP) and consumed energy-restricted diets (250 kcal d^-1 less than their customary diet) for 8 weeks.

RESULTS

WP group lost an average of 3.2 kg, while SP group lost 2.6 kg and the NP group 1.8 kg. However, only the groups that consumed peanuts showed a significant reduction in BMI. WP group presented lower body weight, BMI, waist circumference, total lean mass, and total body fat than the SP group in the eighth week. There was a significant reduction in total cholesterol and low-density lipoprotein (LDL) after 4 weeks of intervention, which was maintained in week-8 for the WP and SP groups. In addition, there was an improvement in platelets and plasma homocysteine with WP group.

CONCLUSION

Our results suggest that the regular intake of the whole peanut as part of an energy-restricted diet showed health benefits since it enhanced body weight loss, besides improving body composition and reducing cholesterol, platelets, and homocysteine concentrations. © 2021 Society of Chemical Industry.

The Potential of Dietary Bioactive Compounds against SARS-CoV-2 and COVID-19-Induced Endothelial Dysfunction

COVID-19 is an endothelial disease. All the major comorbidities that increase the risk for severe SARS-CoV-2 infection and severe COVID-19 including old age, obesity, diabetes, hypertension, respiratory disease, compromised immune system, coronary artery disease or heart failure are associated with dysfunctional endothelium. Genetics and environmental factors (epigenetics) are major risk factors for endothelial dysfunction. Individuals with metabolic syndrome are at increased risk for severe SARS-CoV-2 infection and poor COVID-19 outcomes and higher risk of mortality. Old age is a non-modifiable risk factor. All other risk factors are modifiable. This review also identifies dietary risk factors for endothelial dysfunction. Potential dietary preventions that address endothelial dysfunction and its sequelae may have an important role in preventing SARS-CoV-2 infection severity and are key factors for future research to address. This review presents some dietary bioactives with demonstrated efficacy against dysfunctional endothelial cells. This review also covers dietary bioactives with efficacy against SARS-CoV-2 infection. Dietary bioactive compounds that prevent endothelial dysfunction and its sequelae, especially in the gastrointestinal tract, will result in more effective prevention of SARS-CoV-2 variant infection severity and are key factors for future food research to address.

Dietary Intake of Hydrolyzable Tannins and Condensed Tannins to Regulate Lipid Metabolism

Lipid metabolism disorder is a multifactor issue, which contributes to several serious health consequences, such as obesity, hyperlipidemia, atherosclerosis diabetes, non-alcoholic fatty liver etc. Tannins, applied as natural derived plant, are commonly used in the study of lipid metabolism disease with excellent safety and effectiveness, while producing less toxic and side effects. Meanwhile, recognition of the significance of dietary tannins in lipid metabolism disease prevention has increased. As suggested by existing evidence, dietary tannins can reduce lipid accumulation, block adipocyte differentiation, enhance antioxidant capacity, increase the content of short-chain fatty acids, and lower blood lipid levels, thus alleviating lipid metabolism disorder. This study is purposed to sum up and analyze plenty of documents on tannins, so as to provide the information required to assess the lipid metabolism of tannins.

Morphological, biochemical and histological effects of aqueous extracts of peanut (Arachis hypogaea) on swiss mice in different diets

PURPOSE

To evaluate the morphological, biochemical, and histological effects of aqueous extracts of peanut (skinless and added to 1% skin) in Swiss mice submitted to a high-fat diet.

METHODS

Forty male Swiss mice were divided into four groups (n=10 per group): GI) normocaloric diet; GII) high-fat diet; GIII) high-fat diet + 0.5 mL of peanut extract; GIV) high-fat diet + 0.5 mL of peanut extract + 1% peanut skin. The animals were weighed weekly and euthanized after 12 weeks for histopathological and biochemical analyses. The study was approved by the Animal Use Ethics Committee.

RESULTS

The animals in the GIV group had higher body weight when compared to the other ones. Increase in total cholesterol in GIII, increase in blood glucose in groups GII, GIII and GIV, decrease in serum low-density lipoprotein (LDL) concentration in groups GI and GIV and increase in serum concentration of C-reactive protein in GII were seen. The presence of vacuolar fat deposits was found in animal livers from GII.

CONCLUSIONS

The extracts improved the plasma concentrations of animals that received a high-fat diet, including preventing morphological damage to liver tissue. These benefits were enhanced by the association of peanut shells with the extract.

Proanthocyanidins and Where to Find Them: A Meta-Analytic Approach to Investigate Their Chemistry, Biosynthesis, Distribution, and Effect on Human Health

Proanthocyanidins (PACs) are a class of polyphenolic compounds that are attracting considerable interest in the nutraceutical field due to their potential health benefits. However, knowledge about the chemistry, biosynthesis, and distribution of PACs is limited. This review summarizes the main chemical characteristics and biosynthetic pathways and the main analytical methods aimed at their identification and quantification in raw plant matrices. Furthermore, meta-analytic approaches were used to identify the main plant sources in which PACs were contained and to investigate their potential effect on human health. In particular, a cluster analysis identified PACs in 35 different plant families and 60 different plant parts normally consumed in the human diet. On the other hand, a literature search, coupled with forest plot analyses, highlighted how PACs can be actively involved in both local and systemic effects. Finally, the potential mechanisms of action through which PACs may impact human health were investigated, focusing on their systemic hypoglycemic and lipid-lowering effects and their local anti-inflammatory actions on the intestinal epithelium. Overall, this review may be considered a complete report in which chemical, biosynthetic, ecological, and pharmacological aspects of PACs are discussed.

Composição físico-química e compostos bioativos do extrato aquoso de amendoim sem pele e enriquecido com pele

Resumo Objetivou-se realizar a caracterização físico-química e dos compostos bioativos do extrato aquoso de amendoim sem pele e acrescido de 1% de pele. Os extratos aquosos de amendoim sem e com pele foram caracterizados quanto aos parâmetros: umidade, extrato seco total, cinzas, lipídios, proteínas, teor de sólidos solúveis, acidez titulável, pH, carboidrato e fibras totais, além de compostos fenólicos e flavonoides. Os percentuais de umidade encontrados foram elevados em todas as amostras, resultante de sua base de extrato aquoso produzido na proporção 1:8 (amendoim:água). Observou-se que os extratos aquosos de amendoim sem pele e acrescido de 1% de pele não apresentaram diferença significativa entre si para os parâmetros de pH, como também para sólidos solúveis totais, lipídios e carboidratos. No entanto, a acidez, proteínas, fibras e cinzas apresentaram diferença estatística. Na determinação de compostos fenólicos, notou-se que o extrato aquoso de amendoim com pele apresentou uma quantidade maior quando comparado ao sem pele. Quanto aos flavonoides, a maior quantidade também foi encontrada na amostra com pele, apresentando uma diferença média de 2,52 µg/100 g base úmida. Os extratos aquosos de amendoim com e sem pele mostraram ser uma valiosa alternativa para um melhor aproveitamento do amendoim, proporcionando à população um produto nutricional. A bebida acrescida de 1% de pele enriqueceu o produto quanto ao potencial antioxidante devido às suas maiores concentrações de compostos fenólicos totais e flavonoides.

Extracts of Peanut Skins as a Source of Bioactive Compounds: Methodology and Applications

Peanut skins are a waste product of the peanut processing industry with little commercial value. They are also significant sources of the polyphenolic compounds that are noted for their bioactivity. The extraction procedures for these compounds range from simple single solvent extracts to sophisticated separation schemes to isolate and identify the large range of compounds present. To take advantage of the bioactivities attributed to the polyphenols present, a range of products both edible and nonedible containing peanut skin extracts have been developed. This review presents the range of studies to date that are dedicated to extracting these compounds from peanut skins and their various applications.

Peanut skin extract ameliorates the symptoms of type 2 diabetes mellitus in mice by alleviating inflammation and maintaining gut microbiota homeostasis

In this study, mice with type 2 diabetes mellitus (T2DM) induced by high-fat diet were used to investigate the antidiabetic effect and mechanism of action of peanut skin extract (PSE). Results revealed that the fasting blood glucose, body weight, and food intake of mice with T2DM significantly decreased after they were given PSE. The effects of 80 mg/kg PSE were similar to those of 140 mg/kg metformin (MET). The glucose tolerance and insulin sensitivity of the mice also improved. The composition of intestinal microflora in the mice significantly changed after PSE administration. In particular, no Actinobacteria was detected in the PSE-treated group, and the ratio of Firmicutes to Bacteroidetes was remarkably reduced. PSE also increased the abundance of gut microbiota involved in fatty acid biosynthesis, lipid biosynthesis, and sucrose metabolism. The abundance of gut microbiota related to aminoacyl-tRNA biosynthesis also decreased. Lipopolysaccharide, interleukin (IL)-6, IL-1β and tumor necrosis factor-α in the blood, liver and adipose tissue were reduced by PSE. Similarly, the mRNA expression levels of IkappaB kinase and nuclear factor kappaB in the hypothalamus were reduced by PSE. These results suggested that PSE and MET elicited significant antidiabetic effects by maintaining gut microbiota and inhibiting inflammation.

Enhanced and sustainable pretreatment for bioconversion and extraction of resveratrol from peanut skin using ultrasound-assisted surfactant aqueous system with microbial consortia immobilized on cellulose

In this study, the ultrasound-assisted surfactant aqueous system coupled with microbial consortia immobilized by cellulose has been created as an enhanced and sustainable method for the bioconversion and extraction of resveratrol from peanut skin. Based on central composite design, and several single-factor experiments, we derived the optimal bioconversion and extraction system. Microbial consortia consist of Yeast CICC 1912, Aspergillus oryzae 3.951 and Aspergillus niger 3.3148 were chosen to be immobilized using cellulose. Other treatment conditions include concentration of surfactant as 3% (w/v), temperature as 30 °C, time as 36 h, ultrasonic power as 250 W and liquid to solid ratio as 25:1 mL/g. Under these conditions, we achieved a promising yield of resveratrol 96.58 μg/g, which is 4.02 folds compared to the untreated sample. This sustainable and green method not only enhanced the production of resveratrol but also improved the safety and reliability of the bioconversion and extraction process. Our novel method has shown great potential to realize large-scale bioconversion and extraction of bioactive compounds from plant waste.

Leptin and Adiponectin Signaling Pathways Are Involved in the Antiobesity Effects of Peanut Skin Extract

Excessive food intake and metabolic disorder promote obesity and diabetes. In China, peanut skin is used as a herbal medicine to treat hemophilia, thrombocytopenic purpura, and hepatic hemorrhage. In the present study, we demonstrated that peanut skin extract (PSE) safely reduced appetite, body weight, fat tissue, plasma TG and TC, and blood glucose level in mice with diet-induced obesity (DIO). Moreover, the leptin/leptin receptor/neuropeptide Y (NPY) and adiponectin signaling pathways involved in the antiobesity effects of PSE are confirmed through leptin and adiponectin overexpression and leptin receptor silencing in mice. PSE consisted of oligosaccharide and polyphenol in a mass ratio of 45 : 55, and both parts were important for the antiobesity function of PSE. Our results suggested that PSE can be developed as functional medical food to treat metabolic disorders and obesity.

Proanthocyanidins of Natural Origin: Molecular Mechanisms and Implications for Lipid Disorder and Aging-Associated Diseases

Proanthocyanidins are phytonutrients formed by oligomerization or polymerization of subunits catechin, epicatechin, and their gallic acid esters. Proanthocyanidins are a component of many plants and thus form an integral part of the human diet. Oligomeric proanthocyanidins are currently marketed as medicinal products that target vascular disorders and chronic pathological conditions, many of which are age-associated. Proanthocyanidins are also characterized by their effects on energy homeostasis. Not dissimilar to their chemically synthesized counterparts, naturally extracted proanthocyanidins act via inhibition of lipases, stimulation of energy expenditure, or suppression of appetite. Here we review the current knowledge-base and highlight challenges and future impacts regarding involvement of proanthocyanidins in global lipid metabolism, with a focus on the molecular mechanisms and pathological conditions that progress with aging.

Obesity and Cardiovascular Risk Improvement Using Cacao By-Products in a Diet-Induced Obesity Murine Model

In the production of chocolate, only cocoa seeds are used, generating by-products that are generally discarded, increasing the risk of environmental contamination. Given fiber, carbohydrates, proteins, and flavonoid content the use of cacao pod husks can generate nutraceutical products for human consumption. In contrast, obesity represents a major public health problem worldwide. Cacao derivatives are able to modulate overweight and lipid disorders. The objective of present work was to prepare and characterize products using cacao by-products and analyze their effects on altered cardiometabolic risk markers in an obesity model induced by high fat diet and fructose ingestion in rats. The effects of a pellet and extracts made with outer pod husk and kernel husk for 5 weeks were analyzed in an obesity rat model. The treatments significantly decreased body weight by 39%, systolic blood pressure by 27%, triglycerides by 55%, total cholesterol by 24%, low-density lipoprotein cholesterol by 37%, and the triglycerides/high-density lipoprotein ratio by 54%. Cacao by-products improved the metabolic function of obese animals, without causing secondary effects.

Oligomer Procyanidins from Lotus Seedpod Regulate Lipid Homeostasis Partially by Modifying Fat Emulsification and Digestion

Dietary polyphenols have shown hypolipidemic effects by reducing triglyceride absorption. The mechanisms may involve modifying fat emulsion during digestion in the gastrointestinal tract and suppressing lipase during hydrolysis in the small intestine. In an in vivo study, lotus seedpod oligomeric procyanidin (LSOPC) decreased total serum triglyceride and total cholesterol and elevated the high-density lipoprotein level in the hyperlipidemic rat model. In addition, LSOPC suppressed de novo lipogenesis-related gene expressions. In an in vitro study, the LSOPC-enriched emulsion decreased the mean droplet size from 0.36 to 0.33 μm and increased the viscosity of the emulsion. Moreover, the LSOPC-enriched emulsion improved the antioxidant properties. A digestion model was developed and showed that the particle size of the LSOPC-enriched emulsion increased in the oral cavity. However, an increase and then a significant drop of the particle size was measured in the stomach and small intestine. The free fatty acid release rate was decreased in the LSOPC-enriched emulsion partly ascribed to the inhibition of lipase by LSOPC.

Peanut skin phenolic extract attenuates hyperglycemic responses in vivo and in vitro

Diabetes affects at least 285 million people globally, and this number continues to increase. Clinical complications include impaired glucose metabolism, hyperglycemia, dyslipidemia, atherosclerosis and non-alcoholic fatty liver disease. Evidence has shown that natural phenolics play a protective effect on both the development and management of type 2 diabetes. This study evaluated effects of the extract from peanut skins containing polyphenols on induced- hyperglycemia using in vivo and in vitro methods. A human hepatocellular liver carcinoma cell line (HepG2) was used to investigate the effect of the peanut skin extract on cell viability after exposure to high glucose concentrations. In vivo, the effect of peanut skin extract on an oral glucose tolerance was investigated in human subjects. Fifteen participants aged 21–32 underwent an oral glucose tolerance test with five treatments: 1) 50-gram glucose solution (reference); 2). 50-gram glucose solution, followed by 12 mg of vegi-capsulated maltodextrin; 3) 50-gram glucose solution, followed by 120 mg of vegi-capsulated maltodextrin-encapsulated peanut skin extract; 4). 50-gram glucose solution, followed by 28 grams of unfortified coated peanuts; 5) 50-gram glucose solution, followed by 28 grams of chili lime coated peanuts fortified with encapsulated peanut skin extract. Glucose levels were measured using a continuous monitor. Peanut skin extract was found to attenuate the decrease in cell viability in high glucose treated HepG2 cells, showing a protective effect against hyperglycemia induced cell death. No difference in the glycemic response area under the curve between any treatments using the tolerance test, but the treatment of the peanut skin extract with the glucose reference resulted in a significantly lower peak blood glucose response at 45 minutes, indicating that it was effective at reducing the glycemic response. The present study shows that the phenolic extract of peanut skins has an antidiabetic effect, further confirming their value as a functional food ingredient.

Extraction Technology Can Impose Influences on Peanut Oil Functional Quality: A Study to Investigate the Lipid Metabolism by Sprague-Dawley Rat Model

In this study, peanut oil was prepared by cold pressing (temperature under 60 °C), hot pressing (temperature above 105 °C), and enzyme-assisted aqueous extraction technology. Influences of an extraction technology on the oil fatty acid composition and the content of minor bioactive compounds, including tocopherols, polyphenols, and squalene, were investigated in detail. High-fat-diet Sprague-Dawley (SD) rat model was then established to probe the impact of cold-pressed peanut oil (CPO), hot-pressed peanut oil (HPO), and enzyme-assisted aqueous-extracted peanut oil (EAO) on lipid metabolism outcomes, to explore influences of different extraction technologies on lipid functional quality. Results showed that oleic acid was the predominate fatty acid in the EAO (52.57 ± 0.11%), which was also significantly higher (P < 0.05) than CPO and HPO. The HPO showed higher total tocopherol and polyphenol contents (206.84 ± 6.93 mg/kg and 47.87 ± 6.50 mg GA/kg, respectively) than CPO and EAO (P < 0.05). However, the squalene content in CPO was 475.47 ± 12.75 mg/kg, which was the highest among the three oils (P < 0.05). The animal experiment results revealed that EAO could be more prone to induce lipid accumulation in the liver, which may likely to cause nonalcoholic fatty liver disease. However, the serum lipid profiles indicated that the CPO was more beneficial than the EAO and HPO in lowering the serum low-density lipoprotein cholesterol, alanine aminotransferase, and aspartate aminotransferase contents, and increasing the high-density lipoprotein cholesterol content. All of our efforts indicated that an extraction technology can affect the peanut oil lipid fatty acid composition, the bioactive compounds content, and, correspondingly, the lipid metabolism in SD rats.

Medicinal plants in treatment of hypertriglyceridemia: A review based on their mechanisms and effectiveness

BACKGROUND

Hypertriglyceridemia (HTg) defines as high amounts of triglyceride (TG) in the blood which can lead to serious complications over time. HTg is usually a part of metabolic disorders such as diabetes mellitus, metabolic syndrome, and dyslipidemia. Different medications have been used to treat HTg but experimentally, many herbs have been recommended for treating HTg as an adjuvant therapy. In most cases, the recommendations are based on animal studies and limited evidences exist about their mechanisms and clinical usefulness.

PURPOSE

This review focused on the herbs which have been shown TG lowering effect.

METHOD

The search was done in PubMed, Science Direct, Scopus, Web of Science and Google Scholar databases a 20-year period between 1997 to 2017 with keywords search of medicinal plant, plant extract, hypertriglyceridemia, dyslipidemia, hyperlipidemia, lipoprotein lipase and apolipoprotein.

RESULTS

According to the results, many plants showed positive effects but Allium sativum, Nigella sativa, Curcuma longa, Anethum graveolens and Commiphora mukul had the best TG lowering effect with exact mechanisms of action.

CONCLUSION

It seems that use of these plants as complementary therapeutics or extraction of their active ingredients along with currently available drugs will improve the management of HTg in patients.

A comprehensive review of the value-added uses of peanut (Arachis hypogaea) skins and by-products

Globally, peanut seeds are grown for oil production, peanut butter, confections, snacks and protein extenders, leaving the peanut by-products (skins, peanut hulls) as waste for disposal. Numerous studies have identified the value added attributes of peanut skins and/or peanut skin extracts as an antioxidant, functional food ingredient, animal production feed ingredient, and antimicrobial agent. This manuscript presents a comprehensive review of the food and non-food uses of peanut skins and/or extracts, and new uses of this significant agricultural waste product produced in the peanut industry. An improved comprehensive knowledge and better understanding of the value added uses of peanut skins enables us to better define future food and non-food uses of this agricultural by-product.

Anti-atherosclerosis of oligomeric proanthocyanidins from Rhodiola rosea on rat model via hypolipemic, antioxidant, anti-inflammatory activities together with regulation of endothelial function

BACKGROUND

Rhodiola rosea has been used as a traditional medicine for a long history. Previous studies on oligomeric proanthocyanidins from Rhodiola rosea (OPCRR) have showed that it exhibited significant free radical-scavenging activities, antioxidant activities in aging mice and lipid lowering effects.

HYPOTHESIS/PURPOSE

We hypothesized that OPCRR can improve the atherosclerosis pathological in rats. In the present study, we investigated the effects of OPCRR on the serum lipid profiles, oxidant stress status, inflammatory cytokines and atherosclerotic mediators, and endothelial dysfunction as well as changes in abdominal aorta of atherosclerosis rats.

METHODS

The major components of OPCRR were analyzed by using infrared spectrum and HPLC-ESI-MS. The atherosclerosis rat model was induced by high fat and vitamin D3 feeding for 9 weeks and two OPCRR doses (60 and 120 mg/kg b.w.) were orally administered daily for 9 weeks. The rats were then sacrificed and the blood was collected via abdominal aorta and serum was separated by centrifugated for biochemical analysis. Part of the aorta tissues were excised immediately for histopathological examination and western blotting.

RESULTS

Compared to model group, OPCRR treatments significantly decreased the serum lipid profiles including total cholesterol, total triglycerides, low-density lipoprotein cholesterol (LDL-C) and ox-LDL and increased the high-density lipoprotein cholesterol (HDL-C); significant increased serum antioxidant enzymes (SOD and GSH-Px) and decrease of MDA content as a product of lipid peroxidation; lowered serum levels of TNF-α, IL-1β, IL-6, ICAM-1 and VCAM-1 and enhanced IL-10 level; increased the serum release of nitric oxide and expression of iNOS in aortic, whereas decreased the expression of eNOS.

CONCLUSION

OPCRR can improve the progress of atherosclerosis by regulation of lipid metabolism, restoring of the antioxidant capacities, and attenuation of pro-inflammatory cytokines and chemcytokines release, and improving the endothelial dysfunction indicated by nitric oxide system.

Procyanidin from peanut skin induces antiproliferative effect in human prostate carcinoma cells DU145

In this study, the antiproliferative activity of peanut skin procyanidins (PSP) and six fractions (PSP-1∼6) isolated from PSP by several chromatographic steps on the human prostate cancer DU145 cells were evaluated. The results showed that PSP and PSP-1∼6 significantly inhibited the proliferation of DU145 cells. PSP-2 was the most effective fraction, which was identified as procyanidin B₃ mainly and procyanidin dimer [(E)C-luteolin or keampferol] secondarily. Moreover, the mechanism of antiproliferative activity of PSP-2 was investigated. It was observed that PSP-2 induced apoptotic cell death and cell cycle arrest at S phase in DU145 cells. PSP-2 caused the increase of intracellular ROS level and the decrease of Bcl-2/Bax ratio, and triggered the activation of p53 and caspases-3 in DU145 cells. Our findings demonstrated that procyanidins from peanut skin have the potential to be developed as an anti-prostate cancer agent.

Impact of grape pomace consumption on the blood lipid profile and liver genes associated with lipid metabolism of young rats

Herein, we investigated the effects of grape pomace (GP) in diet on body weight, blood lipid profile, and expression of liver genes associated with lipid metabolism using a young rat model. In this study, twenty female Sprague-Dawley rats at 7 weeks of age were randomly divided into 4 groups, which were fed modified AIN-93G diets containing 0% (control), 6.9%, 13.8%, and 20.7% of GP for 10 weeks. Feed consumption and body weight were weekly determined. Blood samples were obtained at the beginning and end of the feeding period for cholesterol, alanine aminotransferase (ALT), and glucose analysis. At the end of the feeding period, all rats were fasted overnight and euthanized. Heart, kidney, and liver samples were obtained and weighed. Liver tissues were used for gene expression analysis. GP-containing diet did not influence the body weight of the rats. As GP content increased, blood triglyceride and very low density lipoprotein (VLDL) decreased (P < 0.05), high density lipoprotein (HDL) slightly increased but was not statistically significant, total cholesterol (TC) and low density lipoprotein (LDL) significantly increased (P < 0.05), blood glucose decreased, and ALT level slightly increased. The expressions of liver genes associated with fatty acid synthesis and lipid hydrolysis/metabolism were moderately downregulated by the GP diet. The study suggests that regular consumption of a diet containing appropriate amount of GP may help in the reduction of body fat accumulation and prevention of obesity. This is the first study revealing the change in gene expression caused by long-term consumption of GP-containing diet.

Baccaurea angulata fruit juice ameliorates altered hematological and biochemical biomarkers in diet-induced hypercholesterolemic rabbits

Hypercholesterolemia is an important risk factor linked to the alteration of blood hematology and clinical chemistry associated with the development and progression of atherosclerosis. Previous studies have demonstrated the safety and potential health benefits of Baccaurea angulata (BA) fruit. We hypothesized that the oral administration of BA fruit juice could ameliorate the alteration in the hematological and biochemical biomarkers of diet-induced hypercholesterolemic rabbits. The aim of this study was to investigate the effects of different doses of BA juice on the hematological and biochemical biomarkers in normo- and hypercholesterolemic rabbits. Thirty-five healthy adult New Zealand White rabbits were assigned to seven different groups for 90days of diet intervention. Four atherogenic groups were fed a 1% cholesterol diet and 0, 0.5, 1.0, and 1.5mL of BA juice per kg of rabbit daily. The other three normal groups were fed a commercial rabbit pellet diet and 0, 0.5, and 1.0mL of BA juice per kg of rabbit daily. Baseline and final blood samples after 90days of repeated administration BA juice were analyzed for hematological parameters while serum, aortic and hepatic lysates were analyzed for lipid profiles and other biochemical biomarkers. The alteration of the hemopoietic system, physiological changes in serum and tissues lipid profiles and other biochemicals resulting from the consumption of a high-cholesterol diet were significantly (P<.05) ameliorated by the administration of BA juice. Improvements of the biomarkers in rabbits were dose-dependent, markedly enhanced at the highest dose of juice (1.5mL/kg/day). The results suggest potential health benefits of the antioxidant-rich BA fruit juice against hypercholesterolemia-associated hematological and biochemical alterations in the rabbit.

Effect of Dietary Purified Xanthohumol from Hop (Humulus lupulus L.) Pomace on Adipose Tissue Mass, Fasting Blood Glucose Level, and Lipid Metabolism in KK-Ay Mice

We previously showed that xanthohumol-rich hop extract (XRHE, ~18% xanthohumol) exerts anti-obesity effects in rats fed a high-fat diet through regulation of fatty acid metabolism. In this study, we examined the effects of dietary purified xanthohumol from XRHE (PX, ~91.9% xanthohumol) in KK-Ay mice in order to understand the anti-obesity effects of xanthohumol alone because XRHE contains 82% unknown compounds. Dietary consumption of PX significantly inhibited an increase in the visceral fat weight of mice compared to those fed control diet without PX. Plasma leptin level was significantly lower in the PX-fed group than in the control group. Dietary PX lowered hepatic fatty acid synthesis by down-regulation of SREBP1c mRNA expression in the liver. On the other hand, fatty acid β-oxidation in the liver was promoted by dietary PX through the up-regulation of PPARα mRNA expression. Moreover, the fecal levels of fatty acids and carbohydrates increased by dietary PX. PX inhibited lipase or α-amylase activity in vitro. Thus, we found that PX may exert anti-obesity effects through the regulation of lipid metabolism and inhibition of intestinal fat and carbohydrate absorption, and that xanthohumol alone may exert anti-obesity effects.

Análise do extrato aquoso de Arachis hipoagea L. no combate à dislipidemia e ao ganho ponderal de ratos Wistar submetidos à dieta hiperlipídica1

RESUMO: O objetivo desse estudo foi avaliar os efeitos do Extrato Aquoso de Amendoim (EAA) no peso, bioquímica sérica e na histologia hepática de ratos Wistar submetidos a dietas normo e hiperlipídicas. A pesquisa foi realizada utilizando 40 ratos Wistar machos, divididos em quatro grupos (n=10): GA (dieta hiperlipídica), GB (dieta hiperlipídica +EAA), GC (dieta normolipídica) e GD (dieta normolipídica +EAA). Após 8 semanas, os animais foram eutanasiados e foram coletadas amostras sanguíneas para a avaliação de dados bioquímicos (Colesterol total e suas frações, triglicerídeos, uréia, creatinina, AST, ALT e glicemia) e fragmentos do fígado para análise histológica. Os animais do grupo GB tiveram um ganho de peso inferior quando comparados ao GA (XGB= versus XGA= p<0,05), já os grupos GC e GD não obtiveram diferenças estatísticas. Os animais que receberam o EAA tiveram uma redução nos níveis de colesterol (XGB= versus XGA= p<0,05 e XGD= versus XGA= p<0,01), dos triglicerídeos (XGB= versus XGA e XGD= versus XGA= p<0,001) e mais discretamente dos níveis de ALT. A glicemia, uréia e creatina permaneceram dentro dos valores de referência. As amostras hepáticas analisadas, dos ratos dos diferentes grupos, não apresentaram alterações histopatológicas. Conclui-se que O EAA apresentou efeitos preventivos sobre o ganho ponderal e dislipidemia.

Mixture of Peanut Skin Extract and Fish Oil Improves Memory in Mice via Modulation of Anti-Oxidative Stress and Regulation of BDNF/ERK/CREB Signaling Pathways

Long-term use of fish oil (FO) is known to induce oxidative stress and increase the risk of Alzheimer’s disease in humans. In the present study, peanut skin extract (PSE), which has strong antioxidant capacity, was mixed with FO to reduce its side effects while maintaining its beneficial properties. Twelve-week Institute of Cancer Research (ICR) mice were used to conduct animal behavior tests in order to evaluate the memory-enhancing ability of the mixture of peanut skin extract and fish oil (MPF). MPF significantly increased alternations in the Y-maze and cognitive index in the novel object recognition test. MPF also improved performance in the water maze test. We further sought to understand the mechanisms underlying these effects. A significant decrease in superoxide dismutase (SOD) activity and an increase in malonyldialdehyde (MDA) in plasma were observed in the FO group. The MPF group showed reduced MDA level and increased SOD activity in the plasma, cortex and hippocampus. Furthermore, the gene expression levels of brain-derived neurotrophic factor (BDNF) and cAMP responsive element-binding protein (CREB) in the hippocampus were increased in the MPF group, while phosphorylation of protein kinase B (AKT), extracellular signal-regulated kinase (ERK) and CREB in the hippocampus were enhanced. MPF improves memory in mice via modulation of anti-oxidative stress and activation of BDNF/ERK/CREB signaling pathways.

Egg ovotransferrin-derived ACE inhibitory peptide IRW increases ACE2 but decreases proinflammatory genes expression in mesenteric artery of spontaneously hypertensive rats

Scope

Egg ovotransferrin‐derived angiotensin converting enzyme (ACE) inhibitory peptide IRW was previously shown to reduce blood pressure in spontaneously hypertensive rats through reduced vascular inflammation and increased nitric oxide‐mediated vasorelaxation. The main objective of the present study was to investigate the molecular mechanism of this peptide through transcriptome analysis by RNAseq technique.

Methods and results

Total RNA was extracted from kidney and mesenteric arteries; the RNAseq libraries (from untreated and IRW‐treated groups) were constructed and subjected to sequence using HiSeq 2000 system (Illumina) system. A total of 12 764 and 13 352 genes were detected in kidney and mesenteric arteries, respectively. The differentially expressed (DE) genes between untreated and IRW‐treated groups were identified and the functional analysis through ingenuity pathway analysis revealed a greater role of DE genes identified from mesenteric arteries than that of kidney in modulating various cardiovascular functions. Subsequent qPCR analysis further confirmed that IRW significantly increased the expression of ACE‐2, ABCB‐1, IRF‐8, and CDH‐1 while significantly decreased the expression ICAM‐1 and VCAM‐1 in mesenteric arteries.

Conclusion

Our research showed for the first time that ACE inhibitory peptide IRW could contribute to its antihypertensive activity through increased ACE2 and decreased proinflammatory genes expression.

Wheat aleurone fractions and plasma n-3 fatty acids in rats

The main aim of this study was to compare the effects of two wheat aleurone (WA) fractions on circulating n-3 fatty acids in rats. We demonstrated that only the fraction able to induce the highest urinary excretion of polyphenol metabolites (>1µmol) resulted in a significant increase in plasma level of Eicosapentanoic acid (+22%, p < 0.05). While other constituents of whole wheat can be involved in this response, our data suggest that cereals containing high levels of phenolic compounds can increase blood n-3 without affecting n-6 fatty acids. Further studies are required to confirm this hypothesis and explore the underlying biological mechanisms.

Effect of a high-fat meal containing conventional or high-oleic peanuts on post-prandial lipopolysaccharide concentrations in overweight/obese men

BACKGROUND

An increased plasma lipopolysaccharide (LPS) concentration may favour metabolic disorders such as insulin resistance. The meal composition influences plasma LPS concentrations. The present study aimed to investigate the effect of the acute consumption of a high-fat meal (49% of energy from fat) containing conventional or high-oleic peanuts on post-prandial LPS concentrations and its relationship with lipaemia and insulinaemia in overweight and obese men.

METHODS

The test meal consisted of a shake containing conventional peanuts (CVP; n = 21), high-oleic peanuts (HOP; n = 23) or a control biscuit (CT; n = 21). Blood samples were collected in the fasting state and 1, 2 and 3 h post-prandially. LPS, insulin, lipids and glucose concentrations were assessed.

RESULTS

LPS concentrations were lower in CVP [mean (SE) 0.7 (0.5) EU mL(-1) ] and HOP [1.0 (0.9) EU mL(-1) ] groups compared to CT [1.6 (1.2) EU mL(-1) ] at 3 h post-prandially. Triacylglycerol and insulin concentrations increased in all groups. Triacylglycerol started to increase only after 2 h in the CVP and HOP groups. LPS correlated positively with triacylglycerol. Insulin returned to basal concentrations at 3 h only in the CVP and HOP groups.

CONCLUSIONS

The acute consumption of peanuts delayed the increase in serum triacylglycerol and favoured the quicker return of insulin to basal concentrations, especially in the CVP group. Our results suggest that the consumption of conventional or high-oleic peanuts may help to reduce the risk of endotoxaemia and metabolic disorders.

Preparation and characterisation of peanut seed skin polyphenols

Using α-amylase inhibition as a separation guide, polyphenolic compounds from peanut seed skin were prepared. During preparation, specific α-amylase inhibitory activities were increased about 4-fold. High-resolution MALDI-TOF mass spectra showed that the structure of this sample was a series of polyflavan-3-ols, up to 15-mer, composed of catechin/epicatechin units together with several afzelechin/epiafzelechin units and gallocatechin/epigallocatechin units. The observed precious mass values suggest that the polymers consist of both interflavanoid C-C linkages (A-type) and interflavanoid ether linkages (B-type). Oral administration of the polyphenol fraction to rats fed corn starch significantly suppressed an increase in blood glucose levels in a dose dependent manner. Administration of the polyphenol fraction to rats fed maltose or sucrose delayed the increase in blood glucose levels. These results suggest peanut seed skin contains polyphenols with strong α-amylase inhibitory activity, which retard absorption of carbohydrates and mainly function through inhibition of α-amylase.