Sonchus oleraceus L.: ethnomedical, phytochemical and pharmacological aspects

Sonchus oleraceus L. (Asteraceae) is a cosmopolitan species native to Europe commonly known as lettuce, sowthistle, chicory, or fake dandelion, considered a weed. However, for many years in various cultures around the world, it has been used as food and medicinal plant. The aim of this integrative review is to document the ethnomedical, phytochemical, and pharmacological information of this species. Forty-one papers document the use of S. oleraceus to heal of a wide variety of diseases. However, gastrointestinal problems, diabetes, inflammation, infections, hepatitis, wounds, and to consume it as food are the most common uses. On the other hand, only 11 items highlight that the main groups of secondary metabolites in this species are flavonoids and terpene lactones. Finally, 45 items reveal that antioxidant, antimicrobial, antiproliferative and cytotoxic were the most studied pharmacological activities. In vitro and in vivo studies of extracts and components isolated from different parts of S. oleraceus have provided a concrete overview of the pharmacological properties of this species that supports its ethnomedical uses in cultures from different parts of the world. The reports of this species have focused solely on the study of the complete plant, leaves, and aerial parts, so it is necessary to study other parts of this species to search for bioactive compounds. No clinical studies were found, which creates an opportunity to expand scientific knowledge of this species.

Overview of Ethnobotanical-Pharmacological Studies Carried Out on Medicinal Plants from the Serra da Estrela Natural Park: Focus on Their Antidiabetic Potential

The Serra da Estrela Natural Park (NPSE) in Portugal stands out as a well-preserved region abundant in medicinal plants, particularly known for their pharmaceutical applications in diabetes prevention and treatment. This comprehensive review explores these plants' botanical diversity, traditional uses, pharmacological applications, and chemical composition. The NPSE boast a rich diversity with 138 medicinal plants across 55 families identified as traditionally and pharmacologically used against diabetes globally. Notably, the Asteraceae and Lamiaceae families are prevalent in antidiabetic applications. In vitro studies have revealed their significant inhibition of carbohydrate-metabolizing enzymes, and certain plant co-products regulate genes involved in carbohydrate metabolism and insulin secretion. In vivo trials have demonstrated antidiabetic effects, including glycaemia regulation, insulin secretion, antioxidant activity, and lipid profile modulation. Medicinal plants in NPSE exhibit various activities beyond antidiabetic, such as antioxidant, anti-inflammatory, antibacterial, anti-cancer, and more. Chemical analyses have identified over fifty compounds like phenolic acids, flavonoids, terpenoids, and polysaccharides responsible for their efficacy against diabetes. These findings underscore the potential of NPSE medicinal plants as antidiabetic candidates, urging further research to develop effective plant-based antidiabetic drugs, beverages, and supplements.

Exploration of natural flavones' bioactivity and bioavailability in chronic inflammation induced-type-2 diabetes mellitus

Diabetes, being the most widespread illness, poses a serious threat to global public health. It seems that inflammation plays a critical role in the pathophysiology of diabetes. This review aims to demonstrate a probable link between type 2 diabetes mellitus (T2DM) and chronic inflammation during its development. Additionally, the current review examined the bioactivity of natural flavones and the possible molecular mechanisms by which they influence diabetes and inflammation. While natural flavones possess remarkable anti-diabetic and anti-inflammatory bioactivities, their therapeutic use is limited by the low oral bioavailability. Several factors contribute to the low bioavailability, including poor water solubility, food interaction, and unsatisfied metabolic behaviors, while the diseases (diabetes, inflammation, etc.) causing even less bioavailability. Throughout the years, different strategies have been developed to boost flavones' bioavailability, including structural alteration, biological transformation, and innovative drug delivery system design. This review addresses current advancements in improving the bioavailability of flavonoids in general, and flavones in particular. Clinical trials were also analyzed to provide insight into the potential application of flavonoids in diabetes and inflammatory therapies.

Modulation of integrin receptor by polyphenols: Downstream Nrf2-Keap1/ARE and associated cross-talk mediators in cardiovascular diseases

As a group of heterodimeric and transmembrane glycoproteins, integrin receptors are widely expressed in various cell types overall the body. During cardiovascular dysfunction, integrin receptors apply inhibitory effects on the antioxidative pathways, including nuclear factor erythroid 2-related factor 2 (Nrf2)-Kelch like ECH Associated Protein 1 (Keap1)/antioxidant response element (ARE) and interconnected mediators. As such, dysregulation in integrin signaling pathways influences several aspects of cardiovascular diseases (CVDs) such as heart failure, arrhythmia, angina, hypertension, hyperlipidemia, platelet aggregation and coagulation. So, modulation of integrin pathway could trigger the downstream antioxidant pathways toward cardioprotection. Regarding the involvement of multiple aforementioned mediators in the pathogenesis of CVDs, as well as the side effects of conventional drugs, seeking for novel alternative drugs is of great importance. Accordingly, the plant kingdom could pave the road in the treatment of CVDs. Of natural entities, polyphenols are multi-target and accessible phytochemicals with promising potency and low levels of toxicity. The present study aims at providing the cardioprotective roles of integrin receptors and downstream antioxidant pathways in heart failure, arrhythmia, angina, hypertension, hyperlipidemia, platelet aggregation and coagulation. The potential role of polyphenols has been also revealed in targeting the aforementioned dysregulated signaling mediators in those CVDs.

Recent advances in biological properties of brown algae-derived compounds for nutraceutical applications

The increasing demand for nutraceuticals in the circular economy era has driven the research toward studying bioactive compounds from renewable underexploited resources. In this regard, the exploration of brown algae has shown significant growth and maintains a great promise for the future. One possible explanation could be that brown algae are rich sources of nutritional compounds (polyunsaturated fatty acids, fiber, proteins, minerals, and vitamins) and unique metabolic compounds (phlorotannins, fucoxanthin, fucoidan) with promising biological activities that make them good candidates for nutraceutical applications with increased value-added. In this review, a deep description of bioactive compounds from brown algae is presented. In addition, recent advances in biological activities ascribed to these compounds through in vitro and in vivo assays are pointed out. Delivery strategies to overcome some drawbacks related to the direct application of algae-derived compounds (low solubility, thermal instability, bioavailability, unpleasant organoleptic properties) are also reviewed. Finally, current commercial and legal statuses of ingredients from brown algae are presented, considering future therapeutical and market perspectives as nutraceuticals.

Hepatoprotective Mechanism of Ginsenoside Rg1 against Alcoholic Liver Damage Based on Gut Microbiota and Network Pharmacology

Alcoholic liver disease (ALD) is a major public health problem worldwide, which needs to be effective prevention. Ginsenoside Rg1 (GRg1), a bioactive ingredient extracted from ginseng, has benefit effects on health. In this study, 11 potential targets of GRg1 against ALD were firstly obtained by network pharmacology. KEGG pathway enrichment showed that GRg1-target-ALD was closely related to Toll-like receptor (TLR) and nuclear factor-kappa B (NF-κB) signaling pathways. In addition, GRg1 decreased antioxidant levels and increased oxidative levels in alcohol-treated mice, which alleviated oxidative stress-induced hepatic damage. GRg1 enhanced intestinal barrier function via upregulating the levels of tight junction protein and immunoglobulin A. GRg1 also reduced alcohol-induced inflammation by suppressing TLR4/NF-κB pathway, which was consistent with the prediction of network targets. Moreover, GRg1 altered GM population, and Verrucomicrobia, Bacteroidetes, Akkermansia, Bacteroides, Lachnospiraceae_NK4A136_group, and Alloprevotella played positive association with intestinal barrier indicators and negative correlation with hepatic inflammation biomarkers. The results suggest that GRg1 administration might be a promising strategy for protection of alcohol-induced liver damage.

Metabolomics and biochemical insights on the regulation of aging-related diabetes by a low-molecular-weight polysaccharide from green microalga Chlorella pyrenoidosa

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C. pyrenoidosa polysaccharide (CPP) have hypoglycemic activity and oxidation resistance.

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CPP prevents oxidative stress and stimulates insulin via affecting phenylpyruvic acid.

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CPP can regulate the GLP-1R/IL-6R and ZO-1/MMP-2 pathways.

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CPP activated BCL-6 to promote cell survival in brain.

Globally, aging and diabetes are considered prevalent threats to human health. Chlorella pyrenoidosa polysaccharide (CPP) is a natural active ingredient with multiple health benefits including antioxidant and hypolipidemic activities. In this study, the aging-related diabetic (AD) mice model was established to investigate the underlying hypoglycemic and antioxidant mechanisms of CPP. It improved superoxide dismutase, catalase (CAT), glutathione peroxidase (GSH-px), and malondialdehyde activities in liver and insulin secretion. CAT and GSH-px activity in the brain increased after CPP administration. In addition, through histopathological examinations, it was evident that injuries in the liver, brain, jejunum, and pancreas were restored by CPP. This restoration was likely mediated via the activation of glucagon-like peptide-1 receptor/FOXO-1 (forkhead box O1) pathway concurrent with the inhibition of interleukin-6 receptor/FOXO-1 pathway. Furthermore, metabolomics and correlation analysis revealed that CPP possibly relived AD through changes in insulin levels and declined oxidative stress as regulated by phenylpyruvic acid. These findings suggested that CPP exerted antioxidant and hypoglycemic roles in an AD mice model, thereby providing a sound scientific foundation for further development and utilization of CPP.

Computation Screening of Multi-Target Antidiabetic Properties of Phytochemicals in Common Edible Mediterranean Plants

Diabetes mellitus is a metabolic disease and one of the leading causes of deaths worldwide. Numerous studies support that the Mediterranean diet has preventive and treatment effects on diabetes. These effects have been attributed to the special bioactive composition of Mediterranean foods. The objective of this work was to decipher the antidiabetic activity of Mediterranean edible plant materials using the DIA-DB inverse virtual screening web server. A literature review on the antidiabetic potential of Mediterranean plants was performed and twenty plants were selected for further examination. Subsequently, the most abundant flavonoids, phenolic acids, and terpenes in plant materials were studied to predict their antidiabetic activity. Results showed that flavonoids are the most active phytochemicals as they modulate the function of 17 protein-targets and present high structural similarity with antidiabetic drugs. Their antidiabetic effects are linked with three mechanisms of action, namely (i) regulation of insulin secretion/sensitivity, (ii) regulation of glucose metabolism, and (iii) regulation of lipid metabolism. Overall, the findings can be utilized to understand the antidiabetic activity of edible Mediterranean plants pinpointing the most active phytoconstituents.

Utilization of Diaphragma juglandis extract as a natural antioxidant for improving the oxidative stability of soybean oil during deep frying

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Stabilization of oils during deep-frying by Diaphragma juglandis extract was studied.

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A total of 31 polyphenols were determined in Diaphragma juglandis extract.

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The extract is proven to inhibit the deterioration of triglycerides during frying.

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Extract-added frying oils exhibit a lesser increase in aldehydes and alcohols.

Lipid oxidation significantly shortens the life of frying oils, and this challenge can be addressed by using antioxidants. This work aimed to investigate the effect of Diaphragma juglandis extract (DJE) on the oxidative stability of soybean oil during deep frying. Tert-butylhydroquinone (TBHQ) and tea polyphenol (TP) were applied as positive controls. A total of 31 polyphenols were determined in DJE, and catechin, quercitrin, taxifolin, quercetin 3-β-d-glucoside, epicatechin, gallic acid, and 3,4-dihydroxybenzoic acid were the main components. The antioxidants effectively delayed the degradation of triglycerides and inhibited the increase in the contents of p-anisidine, oxidized triglyceride monomers, triglyceride dimers, and triglyceride oligomers, with DJE exhibiting better performance. Moreover, DJE showed better inhibitory effect on the formation of (E)-2-alkenals, (E,E)-2,4-alkadienals, 4-oxo-alkanals, primary alcohols, and secondary alcohols detected by ¹H nuclear magnetic resonance than TBHQ and TP. Therefore, DJE has great potential as an excellent antioxidant in large-scale industrial applications.

Solvents effect on phenolics, iridoids, antioxidant activity, antibacterial activity, and pancreatic lipase inhibition activity of noni (Morinda citrifolia L.) fruit extract

This study focused on the relationship between content levels of phytochemicals and the biological activities of noni (Morinda Citrifolia L.) fruit extracts (NFEs) prepared with traditional solvents and deep eutectic solvents (DESs). The results indicated the total phenolic content in Bet-Gly (Betaine: Glycerol) extracts (11.89 mg GAE/g DW) and total iridoid content in 70% ethanol extracts (26.38 mg CE/g DW) were the highest. A total of 17 compounds were identified and quantified in NFEs. Traditional solvent extracts, except ethyl acetate, exhibited higher antioxidant activities than DESs. Three DES extracts showed higher activities against pancreatic lipase than traditional solvent extracts. Multivariate analysis revealed that the type of extraction solvent exerts a significant influence on the phytochemical compositions and biological activities of NFEs. This study provided valuable information on the efficient extraction of phytochemicals from noni fruits and DESs are promising green solvent for the extraction of bioactive compounds from noni fruits.

Hypoglycaemic and anti-ageing activities of green alga Ulva lactuca polysaccharide via gut microbiota in ageing-associated diabetic mice

Ageing-related type 2 diabetes is a significant public health problem. Particularly, the number of cases and fatality rates of ageing-associated diabetes increase with population ageing. This study aimed to investigate the structural characterisation of Ulva lactuca polysaccharide (ULP) and the hypoglycaemic effect on ageing-associated diabetic mice using gut microbiota variation. Sugar residuals analysis showed that the purified ULP (ULP-1) comprised β-D-Xylp-(1→3)-β-D-Arap-(1→6)-β-D-Galp-(1→6)-β-D-Glcp linked to [→α-L-Rhap-(1→4)-β-D-GlcpA→]_n and α-D-Manp-(1→4)-α-L-Rhap(2SO₃^-)-(1→2)-α-L-Rhap(4SO₃^-)-(1→2)-α-L-Arap-(1→2)-α-L-Rhap-(1→ as its side chains at β-D-Glcp. Moreover, ULP modulated the expression levels of p16^Ink4a, MMP2, FoxO1, GLP-1/GLP-1R, STAT3, and GLUT4 to improve the status of ageing and diabetes, which was concurrent with the increased abundance of Dubosiella, Enterococcus, Romboutsia, Bifidobacterium, Kurthia, Clostridium_sensu_stricto_1, Corynebacterium, Faecalibaculum, Aerococcus and Vibrio. Notably, Dubosiella, Romboutsia, Bifidobacterium, Turicibacter and Clostridium_sensu_stricto_1 could serve as important intermediates for delaying ageing and diabetes. Additionally, the ULP-1 structure is strongly binding interaction with the target protein through hydrogen bonding and Van der Waals force, especially for GLP-1 (-10.34 kcal/mol), p16^Ink4a (-10.51 kcal/mol) and GLP-1R (-8.57 kcal/mol). Moreover, the average length of the hydrogen bond was observed to be 2.36 MPa, which is smaller than that of the traditional hydrogen bond. Therefore, ULP has the potential to function as a nutraceutical to delay or prevent the development of ageing-related type 2 diabetes.

Anti-fatigue and anti-oxidant effects of curcumin supplementation in exhaustive swimming mice via Nrf2/Keap1 signal pathway

Demands for dietary supplements with anti-fatigue effects are growing fast due to increasing societal demands. Moreover, in highly physically active individuals, there are also significant needs for supplements to improve exercise performance. The present study evaluated the potential anti-fatigue and anti-oxidant effects of curcumin in mice using exhaustive swimming test. Male C57BL/6J mice were randomized into six groups: blank control (Rest), swimming control (Con), Vitamin C (Vc), low-dose curcumin (C₅₀), middle-dose curcumin (C₁₀₀), and high-dose curcumin (C₂₀₀). After a 4-week intervention, the mice in all groups except the Rest group were subject to an exhaustive swimming test. Then, mice were sacrificed to examine serum biochemical markers and fatigue-related enzymes. Moreover, the gene and protein expressions of signal transduction factors involved in the Nrf2/Keap1 signaling pathway were measured. The results indicated that curcumin significantly enhanced the exercise tolerance of mice in the exhaustive swimming test. Particularly, the swimming time of mice in the C₁₀₀ group was increased by 273.5% when compared to that of mice in the Con group. The levels of blood urea nitrogen, blood ammonia, lactic acid, creatine kinase and lactate dehydrogenase in the C₁₀₀ group were decreased by 13.3%, 21.0%, 18.6%, 16.7% and 21.9%, respectively, when compared to those of mice in the Con group. Curcumin alleviated exercise-induced oxidative stress and significantly enhanced the activities of superoxide dismutase, catalase and glutathione peroxidase by activating the Nrf2 signaling. These findings indicated that curcumin supplementation exerted remarkable anti-oxidant and anti-fatigue effects in mice, providing additional evidence supporting the use of curcumin as functional food, especially by those engaged in sports-related activities.

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Curcumin exerted remarkable anti-oxidant and anti-fatigue effects in mice.

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Curcumin can activate anti-oxidant response via Nrf2/Keap1 signaling pathway.

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Curcumin greatly enhanced the exercise tolerance of mice in exhaustive swimming test.

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Curcumin alleviated exercise-induced oxidative stress by its anti-oxidant effects.

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Curcumin can be an anti-fatigue promising candidate improving exercise performance.

Anti-inflammatory activity of flavonols via inhibiting MAPK and NF-κB signaling pathways in RAW264.7 macrophages

Fisetin (Fis), quercetin (Que), and myricetin (Myr) are flavonols with similar structure but different number of hydroxyl groups. The present research focused on the anti-inflammatory effect of these three flavonols in lipopolysaccharide-stimulated RAW264.7 cells. The number and site of hydroxyl group in flavonols obviously affected their anti-inflammation activity. These flavonols suppressed the overproduction of nitric oxide. Fis showed the best activity with an inhibition rate of 52% at 20 μM. Moreover, the flavonols reduced the levels of ROS, TNF-α, and IL-6. The mechanistic study showed that they inhibited the activation of NF-κB and MAPK pathways by suppressing the phosphorylation of IκBα, p65, JNK, ERK, p38, MEK, and reducing the nuclear translocation of NF-κB p65. In addition, the metabolism of the flavonols was examined. The results indicated that Fis was both methylated and glucuronidated. Que and Myr were mainly transformed into methylated products. This study highlights the anti-inflammatory activity of flavonols, particularly Fis, which has the potential for the prevention or treatment of inflammation as an adjuvant medicine or food additive.

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Flavonols suppressed the production of NO and ROS.

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Flavonols partially blocked the activation of NF-κB and MAPK pathways.

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Fisetin is an excellent anti-inflammatory reagent.

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The number of hydroxyl group in flavonols obviously affects their anti-inflammation activity.

GR-mediated anti-inflammation of α-boswellic acid: Insights from in vitro and in silico studies

Although multiple bioactivities of α-boswellic acid have been reported, the molecular mechanism of its anti-inflammatory action is not yet clear. Hence, glucocorticoid receptor (GR)-mediated anti-inflammation of α-boswellic acid was investigated in this work. Fluorescence polarization assay suggested that α-boswellic acid bound to GR with IC₅₀ value of 658.00 ± 0.21 μM. Upon binding to α-boswellic acid, GR translocated from cytoplasm into nucleus of HeLa cells, facilitating sequential transcriptional regulation of GR-related genes. Luciferase reporter assay suggested that α-boswellic acid lacked GR transcriptional activity, indicating its potential as a dissociative GR ligand. Interestingly, α-boswellic acid selectively modulated the anti-inflammatory gene CBG (marker for GR transrepression), while leaving the "side-effect" gene TAT (marker for GR transactivation) unaffected in HepG2 cells. Furthermore, α-boswellic acid inhibited lipopolysaccharide-stimulated cytokines production in U937 macrophages, confirming its anti-inflammation property in vitro. Molecular docking showed that both hydrogen-bonding and hydrophobic interactions helped to stabilize α-boswellic acid-GR binding. Their binding stability was further confirmed in a 70-ns dynamics simulation. In summary, α-boswellic acid could bind to and translocate GR but did not induce glucocorticoid response element-mediated transcription. Since α-boswellic acid showed the dissociated characteristic that separated transrepression from transactivation, it might be a selective GR modulator against inflammatory disorders.