Toxicological assessment of the Achyrocline satureioides aqueous extract in the Caenorhabditis elegans alternative model

Achyrocline satureioides, popularly called "marcela" in Brazil, is used in traditional medicine in South America. A. satureioides, inflorescences are used for many conditions, including to minimize the Sars-Cov-2 symptoms. Therefore, the aim of this study was to determine the toxicity profile of A. satureioides aqueous extract (ASAE), using the Caenorhabditis elegans (C. elegans) alternative model. Survival, reproduction, development, and transgenerational assays were performed. The effects of ASAE were investigated under conditions of thermal stress and presence of oxidant hydrogen peroxide (H2O2). In addition, C. elegans strains containing high antioxidant enzyme levels and elevated lineages of daf-16, skn-1 and daf-2 regulatory pathways were examined. The ASAE LC50 value was found to be 77.3 ± 4 mg/ml. The concentration of ASAE 10 mg/ml (frequently used in humans) did not exhibit a significant reduction in worm survival at either the L1 or L4 stage, after 24 or 72 hr treatment. ASAE did not markedly alter the body area. In N2 strain, ASAE (10 or 25 mg/ml) reversed the damage initiated by H2O2. In addition, ASAE protected the damage produced by H2O2 in strains containing significant levels of sod-3, gst-4 and ctl - 1,2,3, suggesting modulation in these antioxidant systems by this plant extract. ASAE exposure activated daf-16 and skn-1 stress response transcriptional pathways independently of daf-2, even under extreme stress. Data suggest that ASAE, at the concentrations tested in C. elegans, exhibits a reliable toxicity profile, which may contribute to consideration for safe use in humans.

Network analysis and experimental verification of Salvia miltiorrhiza Bunge-Reynoutria japonica Houtt. drug pair in the treatment of non-alcoholic fatty liver disease

CONTEXT

There are currently no approved specific clinical drugs for non-alcoholic fatty liver disease (NAFLD). Salvia miltiorrhiza Bunge-Reynoutria japonica Houtt. drug pair (SRDP) has been widely used in the treatment of chronic liver diseases. However, the mechanism of SRDP treating NAFLD remains unclear.

OBJECTIVE

Based on network analysis and in vitro experimental verification, we investigated the effect of SRDP on lipid deposition and explored its possible mechanism for the treatment of NAFLD.

METHODS

The TCMSP platform was used to screen the active metabolites of SRDP and corresponding targets. The GeneCards and OMIM databases were used to screen the NAFLD targets. The drug-disease intersecting targets were extracted to obtain the potential targets. Then the protein-protein interaction (PPI) and drug-active metabolites-target-disease network map was constructed. The DAVID database was performed to GO and KEGG pathway enrichment analysis for the intersecting targets. The core active metabolite and signaling pathway were verified by in vitro experiments.

RESULTS

Network analysis predicted 59 active metabolites and 89 targets of SRDP for the treatment of NAFLD. 112 signaling pathways were enriched for KEGG pathways, including PI3K-AKT signaling pathway,etc. It was confirmed that luteolin, the core active metabolite of SRDP, effectively reduced fat accumulation and intracellular triglyceride content in HepG2 fatty liver cell model. Luteolin could inhibit mTOR pathway by inhibiting PI3K-AKT signaling pathway phosphorylation, thereby activating autophagy to alleviate NAFLD. DISCUSSION AND CONCLUSION: The results of this study validate and predict the possible role of various active metabolites of SRDP in the treatment of NAFLD through multiple targets and signaling pathways. The core active metabolite of SRDP, luteolin can alleviate NAFLD by acting on the PI3K-AKT-mTOR signaling pathway to induce autophagy.

Lipid-Lowering and Anti-Inflammatory Effects of Campomanesia adamantium Leaves in Adipocytes and Caenorhabditis elegans

Obesity is a pandemic disease characterized by lipid accumulation, increased proinflammatory cytokines, and reactive oxygen species. It is associated with the development of comorbidities that lead to death. Additionally, drug treatments developed to control obesity are insufficient and have a variety of adverse effects. Thus, the search for new anti-obesity therapies is necessary. Campomanesia adamantium is a species from the Brazilian Cerrado that has the potential to treat obesity, as described by the antihyperlipidemic activity of its roots. Therefore, this study aimed to investigate the activity of the aqueous extract of C. adamantium leaves (AECa) on the control of reactive species in vitro, on lipid accumulation in adipocytes and Caenorhabditis elegans, and on the production of proinflammatory cytokines in adipocytes. The antioxidant capacity of AECa was observed by its action in scavenging DPPH• free radical, iron-reducing power, and inhibition of β-carotene bleaching. AECa reduced lipid accumulation in preadipocytes and in C. elegans. Moreover, AECa reduced the production of the proinflammatory cytokines MCP-1, TNF-α, and IL-6 in adipocytes. In summary, the antioxidant activity and the ability of AECa to reduce the accumulation of lipids and proinflammatory cytokines indicate, for the first time, the anti-obesity potential of C. adamantium leaves.

Luteolin: A promising multifunctional natural flavonoid for human diseases

Natural products are closely associated with human health. Luteolin (LUT), a flavonoid polyphenolic compound, is widely found in fruits, vegetables, flowers, and herbs. It is noteworthy that LUT exhibits a variety of beneficial pharmacological properties and holds significant potential for clinical applications, particularly in antitumor, anti-convulsion, diabetes control, anti-inflammatory, neuroprotection, anti-oxidation, anti-cardiovascular, and other aspects. The potential mechanism of action has been partially elucidated, including the mediation of NF-κB, toll-like receptor, MAPK, Wnt/β-catenin, PI3K/Akt, AMPK/mTOR, and Nrf-2, among others. The review that aimed to comprehensively consolidate essential information on natural sources, pharmacological effects, therapeutic and preventive potential, as well as potential mechanisms of LUT. The objective is to establish a theoretical basis for the continued development and application of LUT.

Flavonoids intake and weight-adjusted waist index: insights from a cross-sectional study of NHANES

This study conducted data on 15,446 adults to explore the impact of flavonoids on weight-adjusted waist index (WWI). This was a nationwide cross-sectional study among US adults aged 20 years or older. Dietary intake of flavonoids was assessed through 24-h recall questionnaire. WWI was calculated by dividing waist circumference (WC) by the square root of weight. We utilized weighted generalized linear regression to evaluate the association between flavonoids intake and WWI, and restricted cubic splines (RCS) to explore potential non-linear relationships. Our findings indicated that individuals with lower WWI experienced a notable increase in their consumption of total flavonoids, flavanones, flavones, flavan-3-ols, and anthocyanidins intake (β (95% CI); -0.05(-0.09, -0.01); -0.07(-0.13, 0.00); -0.07(-0.11, -0.02); -0.06(-0.11, 0.00); -0.13(-0.18, -0.08), respectively), with the exception of flavonols and isoflavones. Additionally, consumption of total flavonoids, flavonols, flavanones, isoflavones, and flavan-3-ols had a non-linear relationship with WWI (all P for non-linearity < 0.05). Furthermore, the effect of total flavonoids on WWI varied in race (P for interaction = 0.011), gender (P for interaction = 0.038), and poverty status (P for interaction = 0.002). These findings suggested that increase the intake of flavonoids might prevent abdominal obesity, but further prospective studies are requested before dietary recommendation.

Purification of Phenolic Compounds from Camellia polyodonta Flower: Composition Analysis, Antioxidant Property, and Hypolipidemic Activity In Vitro and In Vivo

Camellia polyodonta flowers are rich sources of phenolics and less attention has been paid to their potential biological activity. This study aims to explore the crude extracts and resulting purified fractions (CPFP-I, II, III, and IV) through compositional analysis and antioxidant and hypolipidemic activities in vitro and in vivo. Among four fractions, CPFP-II contained the highest total phenolic content and flavonoid content, while CPFP-III exhibited the greatest total proanthocyanidin content. Among the 14 phenolic compounds, CPFP-II displayed the highest content of procyanidin B2, B4, and C1, whereas CPFP-III contained the highest amount of 1,2,3,6-tetragalloylglucose. The DPPH, ABTS, and FRAP assessments demonstrated a consistent trend: CPFP-II > CPFP-III > CPFP-I > CPFP-IV. In vivo experiments showed that that all four fractions significantly reduced lipid levels in hyperlipidemic C. elegans (p < 0.05), with CPFP-II exhibiting the most potent effect. Furthermore, CPFP-II effectively bound to bile acids and inhibited the enzymatic activity of pancreatic lipase in vitro. Consequently, CPFP-II should be prioritized as a promising fraction for further exploration and should provide substantial support for the feasibility of the C. polyodonta flower as a natural alternative.

Chronic neurotoxicity of Tetrabromobisphenol A: Induction of oxidative stress and damage to neurons in Caenorhabditis elegans

Tetrachlorobisphenol A (TCBPA) has been used as an alternative flame retardant in various fields. However, the long-term effects of TCBPA on the nervous system remain unclear. Thus, Caenorhabditis elegans (L4 larvae) were selected as a model animal to investigate the neurotoxic effects and underlying mechanisms after 10 d of TCBPA exposure. Exposure to TCBPA (0.01-100 μg/L) decreased locomotive behavior in a concentration-dependent manner. In addition, reactive oxygen species (ROS) formation and lipofuscin accumulation were significantly increased, and the expression of sod-3 was upregulated in the exposed nematodes, indicating that TCBPA exposure induced oxidative damage. Furthermore, 100 μg/L TCBPA exposure caused a reduction in dopamine and serotonin levels, and damage in dopaminergic and serotoninergic neurons, which was further confirmed by the downregulated expression of related genes (e.g., dop-1, dop-3, cat-1, and mod-1). Molecular docking analysis demonstrated the potential of TCBPA to bind to the neurotransmitter receptor proteins DOP-1, DOP-3, and MOD-1. These results indicate that chronic exposure to TCBPA induces neurotoxic effects on locomotive behavior, which is associated with oxidative stress and damage to dopaminergic and serotoninergic neurons.

Molecular characterization of Fusarium venenatum-based microbial protein in animal models of obesity using multi-omics analysis

Microbial protein, produced by fermentation of Fusarium venenatum is a promising candidate alternative protein source. Previous study has demonstrated its ability to improve hyperlipidemia in rats, yet the related mechanism remains unclear. In this study, we aimed to evaluate the potential of F. venenatum as an alternative protein source and its impact on lipid metabolism using multi-omics analysis. Initial experiments with Caenorhabditis elegans revealed that F. venenatum enhanced longevity, improved immune responses, and reduced lipid metabolism by downregulating fat synthesis-related genes. Subsequently, we conducted experiments with mice on a high-fat diet to confirm the anti-obesity effects of F. venenatum. The groups fed F. venenatum showed improved lipid profiles and reduced hepatic fat accumulation. Furthermore, fecal metabolomic analysis showed higher excretion of primary bile acid and cholesterol in the groups fed F. venenatum which might lead to a decrease in lipid digestion and hepatic fat accumulation. Collectively, this series of experiments revealed the potential of F. venenatum as a sustainable alternative protein and its application as an anti-obesity supplement.

Lipid lowering and anti-ageing effects of edible flowers of Viola x wittrockiana Gams in a Caenorhabditis elegans obese model

Life expectancy has increased considerably in the last decades, clearing the way for preventive medicine. The ingestion of healthy foods or ingredients to improve health is gaining attention and edible flowers entail a promising source of bioactive compounds. The aim of this work was to study the anti-ageing and anti-obesity properties of an extract obtained from an edible flower Viola x wittrockiana though in vitro and in vivo methodologies with Caenorhabditis elegans as a model. The capacity to inhibit the enzymes α-glucosidase and lipase as well as to prevent advance glycation end-product (AGE) formation was tested in vitro. Caenorhabditis elegans was used as an obesity in vivo model to assess the effects of the extract on fat accumulation, development, progeny and health span. Viola flowers showed lower IC50 values in the α-glucosidase assay than the reference drug acarbose and exerted a higher inhibition of AGE formation than the reference substance aminoguanidine; the extract also showed pancreatic lipase inhibiting properties. Moreover, the extract lowered fat storage of C. elegans in a dose-dependent manner, up to 90.37% at the highest tested dose, and improved health span biomarkers such as lipofuscin accumulation and progeny availability. Our results demonstrate, for the first time, the anti-obesogenic and anti-ageing activity of Viola x wittrockiana flowers and their potential use as functional foods and nutraceuticals.

Zein-based nanospheres and nanocapsules for the encapsulation and oral delivery of quercetin

In this study, the ability of zein nanospheres (NS) and zein nanocapsules containing wheat germ oil (NC) to enhance the bioavailability and efficacy of quercetin was evaluated. Both types of nanocarriers had similar physico-chemical properties, including size (between 230 and 250 nm), spherical shape, negative zeta potential, and surface hydrophobicity. However, NS displayed a higher ability than NC to interact with the intestinal epithelium, as evidenced by an oral biodistribution study in rats. Moreover, both types of nanocarriers offered similar loading efficiencies and release profiles in simulated fluids. In C. elegans, the encapsulation of quercetin in nanospheres (Q-NS) was found to be two twice more effective than the free form of quercetin in reducing lipid accumulation. For nanocapsules, the presence of wheat germ oil significantly increased the storage of lipids in C. elegans; although the incorporation of quercetin (Q-NC) significantly counteracted the presence of the oil. Finally, nanoparticles improved the oral absorption of quercetin in Wistar rats, offering a relative oral bioavailability of 26% and 57% for Q-NS and Q-NC, respectively, compared to a 5% for the control formulation. Overall, the study suggests that zein nanocarriers, particularly nanospheres, could be useful in improving the bioavailability and efficacy of quercetin.

Antidiabetic and anti-obesity properties of a polyphenol-rich flower extract from Tagetes erecta L. and its effects on Caenorhabditis elegans fat storages

Diabetes mellitus (DM) is a metabolic disease characterized by a high blood sugar level that can cause severe complications to the organism or even death when not treated. However, certain dietary habits and foods may have beneficial effects on this condition. A polyphenolic-rich extract (containing hyperoside, isoquercitrin, quercetin, ellagic acid, and vanillic acid) of Tageres erecta L. (T. erecta) was obtained from yellow and orange flowers using an ethanolic Soxhlet extraction. These extracts were screened for antidiabetic and anti-obesity properties using in vitro and in vivo procedures. The capacity to inhibit the enzymes lipase and α-glucosidase, as well as the inhibition of advance glycation end-products (AGEs) was tested in vitro. Caenorhabditis elegans (C. elegans) was used as an obesity in vivo model to assess extracts effects on fat accumulation using the wild-type strain N2 and a mutant with no N3 fatty acid desaturase activity BX24. Extracts from both cultivars (yellow and orange) T. erecta presented in vitro inhibitory activity against the enzymes lipase and α-glucosidase, showing lower IC₅₀ values than acarbose (control). They also showed important activity in preventing AGEs formation. The polyphenol-rich matrices reduced the fat content of obese worms in the wild-type strain (N2) down to levels of untreated C. elegans, with no significant differences found between negative control (100% reduction) and both tested samples (p < 0.05). Meanwhile, the fat reduction was considerably lower in the BX24 mutants (fat-1(wa-9)), suggesting that N3 fatty acid desaturase activity could be partially involved in the T. erecta flower effect. Our findings suggested that polyphenols from T. erecta can be considered candidate bioactive compounds in the prevention and improvement of metabolic chronic diseases such as obesity and diabetes.

The activity comparison of six dietary flavonoids identifies that luteolin inhibits 3T3-L1 adipocyte differentiation through reducing ROS generation

Mitochondrial reactive oxygen species (ROS)generation plays an essential role in the process of adipocyte differentiation and is involved in the development of obesity and associated metabolic diseases. Various dietary flavonoids possess the substantial anti-adipogenic activity. However, it is unclear whether these flavonoids inhibit adipocyte differentiation by reducing ROS generation. In this study, the effects of six common dietary flavonoids on adipocyte differentiation were assessed in 3T3-L1 cells. The flavonoids with the same backbone of 5,7-dihydroxylflavone, including flavones apigenin, chrysin, luteolin and flavonols kaempferol, myricetin, quercetin, dose-dependently inhibited 3T3-L1 adipocyte differentiation, suggesting an associated hierarchy of inhibitory capability: luteolin > quercetin > myricetin > apigenin/kaempferol > chrysin. Meanwhile, six flavonoids were found to inhibit adipogenic gene expression and the early stage of adipocyte differentiation. Among the tested flavonoids, luteolin significantly reduced both intracellular and mitochondrial ROS generation during adipocyte differentiation. Further, luteolin treatment depressed the elevation of H₂O₂ concentration in the early stage of 3T3-L1 differentiation and reversed the facilitated effects of exogenous H₂O₂ on 3T3-L1 adipocyte differentiation and ROS generation. Altogether, the activity comparison of six dietary flavonoids identifies that luteolin inhibits 3T3-L1 adipocyte differentiation through reducing ROS generation, elucidating a new mechanism underlying the anti-adipogenic actions of flavonoids.

Carbon price forecasting using multiscale nonlinear integration model coupled optimal feature reconstruction with biphasic deep learning

Precise carbon price forecasting matters a lot for both regulators and investors. The improvement of carbon price forecasting can not only provide investors with rational advice but also make for energy conservation and emission reduction. But traditional methods do not perform well in prediction because of the nonlinearity and non-stationarity of carbon price. In this study, an innovative multiscale nonlinear integration model is proposed to improve the accuracy of carbon price forecasting, which combines optimal feature reconstruction and biphasic deep learning. For one thing, the optimal feature reconstruction, including variational mode decomposition (VMD) and sample entropy (SE), is used to extract different features from the original carbon price effectively. For another thing, biphasic deep learning based on deep recurrent neural network (DRNN) and gate recurrent unit (GRU) is applied to predict carbon price. DRNN, a novel framework of deep learning, is applied to predict each component. Meanwhile, GRU is used for nonlinear integration, and the final prediction of carbon price can be acquired through this procedure. For illustration and comparison, this study takes carbon price from Beijing, Hubei, and Shanghai in China as sample data to examine the capability of the proposed model. The empirical result proves that the new hybrid model can improve the carbon price predictive accuracy in consideration of statistical measurement. Hence, the novel hybrid model can be considered as an efficient way of predicting carbon prices.

Luteolin loaded on zinc oxide nanoparticles ameliorates non-alcoholic fatty liver disease associated with insulin resistance in diabetic rats via regulation of PI3K/AKT/FoxO1 pathway

OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) is a worldwide health problem with high prevalence and morbidity associated with obesity, insulin resistance, type 2 diabetes mellitus (T2DM), and dyslipidemia. Nano-formulation of luteolin with Zn oxide in the form of Lut/ZnO NPs may improve the anti-diabetic property of each alone and ameliorate the insulin resistance thus management of NAFLD. This study aimed to measure the efficiency of Lut/ZnO NPs against insulin resistance coupled with NAFLD and T2DM.

METHODS

A diabetic rat model with NAFLD was induced by a high-fat diet and streptozotocin (30 mg/kg I.P). Serum diabetogenic markers levels, lipid profile, and activity of liver enzymes were measured beside liver oxidative stress markers. Moreover, the hepatic expressions of PI3K/AKT/FoxO1/SERBP1c as well as heme oxygenase-1 were measured beside the histopathological examination.

RESULTS

Lut/ZnO NPs treatment effectively reduced hyperglycemia, hyperinsulinemia, and ameliorated insulin resistance. Additionally, Lut/ZnO NPs improved the hepatic functions, the antioxidant system, and reduced the oxidative stress markers. Furthermore, the lipid load in the liver, as well as the circulating TG and TC, was minified via the suppression of lipogenesis and gluconeogenesis. Moreover, Lut/ZnO NPs activated the PI3K/AKT signaling pathway, hence inactivating FoxO1, therefore enhancing the hepatic cells' insulin sensitivity.

CONCLUSION

Lut/ZnO NPs have a hepatoprotective effect and may relieve the progression of NAFLD by alleviating insulin resistance, ameliorating the antioxidant status, and regulating the insulin signal pathway.

Eleutheroside E reduces intestinal fat accumulation in Caenorhabditis elegans through neuroendocrine signals

BACKGROUND

Acanthopanax senticosus, a small woody shrub of the family Araliaceae, can be used as a functional food with multiple biological activities. Eleutheroside E (EE), an important active component of A. senticosus, has significant effects on neurological diseases. However, whether EE can regulate lipid metabolism has not been reported. The brain can mediate communication between neurons and intestinal cells through long-distance neuroendocrine signals. We speculated that EE might regulate the intestinal lipid metabolism of Caenorhabditis elegans through neuroendocrine signals.

RESULTS

First, we found that EE reduced the intestinal fat content of C. elegans, without affecting development, reproduction, food intake or movement. In addition, EE significantly regulated genes and metabolites related to lipid metabolism. EE extensively affected fatty acid synthesis, β-oxidation and lipolysis processes, and regulated the content of various fatty acid and lipid metabolism intermediates. We finally proved that EE reduced intestinal fat storage through serotonin and neuropeptide flp-7-npr-22 pathways in the nervous system.

CONCLUSION

EE is expected to be a functional food that regulates lipid metabolism. © 2022 Society of Chemical Industry.

Noise Induced Depression-Like Behavior, Neuroinflammation and Synaptic Plasticity Impairments: The Protective Effects of Luteolin

Noise is a kind of sound that causes agitation and harms human health. Studies have shown that noise can lead to neuroinflammation, damage to synaptic plasticity and altered levels of neurotransmitters that may result in depression. The present study demonstrated that luteolin exerted antidepressant-like effects by improving neuroinflammation in a mouse model of noise-induced depression. Luteolin significantly alleviated noise-induced depression-like behavior. Notably, luteolin treatment not only remarkably ameliorated noise-induced inflammation in the hippocampus and prefrontal cortex, but also increased synapsin. Furthermore, luteolin treatment significantly increased the contents of serum 5-hydroxytryptamine and norepinephrine in noise-induced mice. In sum, luteolin exerts antidepressant effects indepression-like mice caused by noise, which can serve as a potential agent for the treatment of chronic noise-induced depression.

Neuroprotective Natural Products’ Regulatory Effects on Depression via Gut–Brain Axis Targeting Tryptophan

L-tryptophan (Trp) contributes to regulating bilateral communication of the gut–brain axis. It undergoes three major metabolic pathways, which lead to formation of kynurenine, serotonin (5-HT), and indole derivatives (under the control of the microbiota). Metabolites from the principal Trp pathway, kynurenic acid and quinolinic acid, exhibit neuroprotective activity, while picolinic acid exhibits antioxidant activity, and 5-HT modulates appetite, sleep cycle, and pain. Abnormality in Trp plays crucial roles in diseases, including depression, colitis, ulcer, and gut microbiota-related dysfunctions. To address these diseases, the use of natural products could be a favorable alternative because they are a rich source of compounds that can modulate the activity of Trp and combat various diseases through modulating different signaling pathways, including the gut microbiota, kynurenine pathway, and serotonin pathway. Alterations in the signaling cascade pathways via different phytochemicals may help us explore the deep relationships of the gut–brain axis to study neuroprotection. This review highlights the roles of natural products and their metabolites targeting Trp in different diseases. Additionally, the role of Trp metabolites in the regulation of neuroprotective and gastroprotective activities is discussed. This study compiles the literature on novel, potent neuroprotective agents and their action mechanisms in the gut–brain axis and proposes prospective future studies to identify more pharmaceuticals based on signaling pathways targeting Trp.

Comparative and Combined Effects of Epigallocatechin-3-gallate and Caffeine in Reducing Lipid Accumulation in Caenorhabditis elegans

Epigallocatechin-3-gallate (EGCG) and caffeine, two phytochemicals found in a wide range of natural dietary sources, have been reported to have protective effects against hyperlipidemia, a major risk factor for cardiovascular disease. However, their relative efficacy and synergy in lowering lipid level are unclear. This study intended to compare lipid-lowering activity of EGCG and caffeine and to elucidate their joint action using Caenorhabditis elegans (C. elegans) as a model organism. The worms were exposed to EGCG, caffeine or both agents, and lipid accumulation determined by levels of total lipids, triglycerides and cholesterol was monitored. A 3 × 3 factorial design combined with response surface methodology was used to characterize the nature of interactive effects. Total lipids, triglycerides and cholesterol in C. elegans were reduced by either EGCG or caffeine in a dose-dependent manner, with EGCG displaying a stronger lipid-lowering efficacy than caffeine. Overall, the EGCG/caffeine combination for lowering lipids was more effective than either substance alone. Factorial regression models revealed that the combination was antagonistic for total lipid reduction, perhaps due to a "ceiling" effect, and was synergistic for triglyceride-lowering and additive for cholesterol-lowering. Taken together, our work proposes the use of a combination of EGCG and caffeine as an alternative dietary intervention for the prevention of hyperlipidemia, and additionally highlights the suitability of C. elegans model for evaluating lipid-lowering capacity of natural products.

Vitexin and Isovitexin Act Through Inhibition of Insulin Receptor to Promote Longevity and Fitness in Caenorhabditis elegans

SCOPE

Vitexin and isovitexin are natural plant nutraceuticals for human health and longevity. This research investigated the underlying mechanism of vitexin and isovitexin on aging and health. The vital role of DAF-2/IGFR was illustrated in the insulin/insulin-like growth signaling pathway (IIS) modulated by vitexin and isovitexin.

METHODS AND RESULTS

In vitro, in vivo models and molecular docking methods were performed to explore the antiaging mechanism of vitexin and isovitexin. Vitexin and isovitexin (50 and 100 μM) extended the lifespan of C. elegans. The declines of pharyngeal pumping and body bending rates, and the increase of intestinal lipofuscin accumulation, three markers of aging, were postponed by vitexin and isovitexin. These compounds inhibited the IIS pathway in a daf-16-dependent manner, subsequently increasing the expression of DAF-16 downstream proteins and genes in nematodes. Molecular docking studies demonstrated that these compounds might inhibit insulin signal transduction by binding to the crucial amino acid residue ARG1003 in the pocket of the insulin-like growth factor-1 receptor (IGFR). Western blot indicated that IGFR, PI3K and AKT kinase expressions in senescent cells is decreased after vitexin and isovitexin treatment.

CONCLUSION

Vitexin and isovitexin might inhibit IIS pathway by occupying the ATP-binding site pocket of IGFR, subsequently decreasing IGFR expression, thereby promoting longevity and fitness. This article is protected by copyright. All rights reserved.

Pediococcus acidilactici CECT9879 (pA1c) Counteracts the Effect of a High-Glucose Exposure in C. elegans by Affecting the Insulin Signaling Pathway (IIS)

The increasing prevalence of metabolic syndrome-related diseases, including type-2 diabetes and obesity, makes it urgent to develop new alternative therapies, such as probiotics. In this study, we have used Caenorhabditis elegans under a high-glucose condition as a model to examine the potential probiotic activities of Pediococcusacidilactici CECT9879 (pA1c). The supplementation with pA1c reduced C. elegans fat accumulation in a nematode growth medium (NGM) and in a high-glucose (10 mM) NGM medium. Moreover, treatment with pA1c counteracted the effect of the high glucose by reducing reactive oxygen species by 20%, retarding the aging process and extending the nematode median survival (>2 days in comparison with untreated control worms). Gene expression analyses demonstrated that the probiotic metabolic syndrome-alleviating activities were mediated by modulation of the insulin/IGF-1 signaling pathway (IIS) through the reversion of the glucose-nuclear-localization of daf-16 and the overexpression of ins-6 and daf-16 mediators, increased expression of fatty acid (FA) peroxisomal β-oxidation genes, and downregulation of FA biosynthesis key genes. Taken together, our data suggest that pA1c could be considered a potential probiotic strain for the prevention of the metabolic syndrome-related disturbances and highlight the use of C. elegans as an appropriate in vivo model for the study of the mechanisms underlying these diseases.

Polysaccharides from mulberry (Morus alba L.) leaf prevents obesity by inhibiting pancreatic lipase in high-fat diet induced mice

Pancreatic lipase (PL) is a key enzyme related to the prevention and treatment of obesity. The aim of the study was to evaluate the inhibitory effects of mulberry leaf polysaccharides (MLP) on PL and possible interaction mechanism, inhibition on lipid accumulation in vitro and in vivo. The results revealed that MLP had obvious inhibitory effects on PL (P < 0.05). The interaction of MLP-PL complexes was in a spontaneous way driven by enthalpy, and hydrogen bonds were the main factors in the binding. MLP could significantly inhibit the development of lipid accumulation in HepG2 cells (P < 0.05). Furthermore, consumption of high-fat diet containing MLP showed protective effects on liver and adipose tissue damages in mice, and inhibited the lipid absorption in digestive tract. MLP also significantly reduced the increased expression level of pancreatic digestive enzymes (P < 0.05). The study indicated that the anti-obesity effect of MLP might be caused by inhibition of lipid absorption via reducing PL activity.

Adipose and non-adipose perspectives of plant derived natural compounds for mitigation of obesity

ETHNOPHARMACOLOGICAL RELEVANCE

Phyto-preparations and phyto-compounds, by their natural origin, easy availability, cost-effectiveness, and fruitful traditional uses based on accumulated experiences, have been extensively explored to mitigate the global burden of obesity.

AIM OF THIS REVIEW

The review aimed to analyse and critically summarize the prospect of future anti-obesity drug leads from the extant array of phytochemicals for mitigation of obesity, using adipose related targets (adipocyte formation, lipid metabolism, and thermogenesis) and non-adipose targets (hepatic lipid metabolism, appetite, satiety, and pancreatic lipase activity). Phytochemicals as inhibitors of adipocyte differentiation, modulators of lipid metabolism, and thermogenic activators of adipocytes are specifically discussed with their non-adipose anti-obesogenic targets.

MATERIALS AND METHODS

PubMed, Google Scholar, Scopus, and SciFinder were accessed to collect data on traditional medicinal plants, compounds derived from plants, their reported anti-obesity mechanisms, and therapeutic targets. The taxonomically accepted name of each plant in this review has been vetted from "The Plant List" (www.theplantlist.org) or MPNS (http://mpns.kew.org).

RESULTS

Available knowledge of a large number of phytochemicals, across a range of adipose and non-adipose targets, has been critically analysed and delineated by graphical and tabular depictions, towards mitigation of obesity. Neuro-endocrinal modulation in non-adipose targets brought into sharp dual focus, both non-adipose and adipose targets as the future of anti-obesity research. Numerous phytochemicals (Berberine, Xanthohumol, Ursolic acid, Guggulsterone, Tannic acid, etc.) have been found to be effectively reducing weight through lowered adipocyte formation, increased lipolysis, decreased lipogenesis, and enhanced thermogenesis. They have been affirmed as potential anti-obesity drugs of future because of their effectiveness yet having no threat to adipose or systemic insulin sensitivity.

CONCLUSION

Due to high molecular diversity and a greater ratio of benefit to risk, plant derived compounds hold high therapeutic potential to tackle obesity and associated risks. This review has been able to generate fresh perspectives on the anti-diabetic/anti-hyperglycemic/anti-obesity effect of phytochemicals. It has also brought into the focus that many phytochemicals demonstrating in vitro anti-obesogenic effects are yet to undergo in vivo investigation which could lead to potential phyto-molecules for dedicated anti-obesity action.

Dietary Luteolin: A Narrative Review Focusing on Its Pharmacokinetic Properties and Effects on Glycolipid Metabolism

Luteolin, a flavone subclass of flavonoids, is commonly found in food plants and has multiple biological activities. Recently, evidence is growing with regard to the potential of luteolin intake to beneficially affect glycolipid metabolism disorders (GLMDs), particularly insulin resistance, diabetes, and obesity. The aim of this contribution is to provide an overview of recent advances in identifying and understanding the pharmacokinetic properties (absorption, metabolism, and bioavailability) of luteolin, its regulatory effects on glycolipid metabolism, and the underlying mechanisms of action of luteolin in the brain, liver, adipose tissues, and other tissues/organs. Collectively, luteolin or its principal metabolites may contribute to counteracting GLMDs, especially for human obesity and diabetes.

Phenolic Compounds Reduce the Fat Content in Caenorhabditis elegans by Affecting Lipogenesis, Lipolysis, and Different Stress Responses

Supplementation with bioactive compounds capable of regulating energy homeostasis is a promising strategy to manage obesity. Here, we have screened the ability of different phenolic compounds (myricetin, kaempferol, naringin, hesperidin, apigenin, luteolin, resveratrol, curcumin, and epicatechin) and phenolic acids (p-coumaric, ellagic, ferulic, gallic, and vanillic acids) regulating C. elegans fat accumulation. Resveratrol exhibited the strongest lipid-reducing activity, which was accompanied by the improvement of lifespan, oxidative stress, and aging, without affecting worm development. Whole-genome expression microarrays demonstrated that resveratrol affected fat mobilization, fatty acid metabolism, and unfolded protein response of the endoplasmic reticulum (UPRER), mimicking the response to calorie restriction. Apigenin induced the oxidative stress response and lipid mobilization, while vanillic acid affected the unfolded-protein response in ER. In summary, our data demonstrates that phenolic compounds exert a lipid-reducing activity in C. elegans through different biological processes and signaling pathways, including those related with lipid mobilization and fatty acid metabolism, oxidative stress, aging, and UPR-ER response. These findings open the door to the possibility of combining them in order to achieve complementary activity against obesity-related disorders.

Insights into the potential benefits of black soybean (Glycine max L.) polyphenols in lifestyle diseases

Black soybean (Glycine max L.), a cultivar containing abundant polyphenols in its seed coat such as anthocyanins and flavan-3-ols, has been reported to possess various health benefits toward lifestyle diseases. In this review article, the safety evaluation of polyphenol-rich black soybean seed coat extract (BE) and absorption of BE polyphenols are summarized. Additionally, we describe the antioxidant activity of BE polyphenols and their ability to induce antioxidant enzymes. The health benefits of BE and its polyphenols, such as anti-obesity and anti-hyperglycemic activities through the activation of AMP-activated protein kinase and translocation of glucose transporter 4, respectively, are also discussed. Furthermore, we found that black soybean polyphenols were involved in the improvement of vascular function. These emerging data require further investigation in scientific studies and human trials to evaluate the prevention of lifestyle diseases using black soybean polyphenols.

Kahweol Reduces Food Intake of Caenorhabditis elegans

The coffee diterpene kahweol may contribute to the anti-obesity effects of coffee but its physiological effects have yet to be elucidated. Caenorhabditis elegans is used as an animal model in obesity research because its lipid metabolism is conserved in humans. The goal was to investigate kahweol's effects on lipid metabolism in C. elegans. Kahweol at 120 μM reduced fat accumulation by 17% compared to the control, which was associated with a reduced food intake. Kahweol did not reduce fat in eat-2 mutants, which have a disrupted pharynx contraction rate, suggesting that the fat-lowering effects of kahweol were dependent on food intake. Lipid metabolism-related gene homologues of tubby protein (tub-1), enoyl-CoA hydratase (ech-1.1), adipose triglyceride lipase (atgl-1), insulin/insulin-like growth receptor (daf-2), and forkhead box O transcription factor (daf-16) were also associated with changes in food intake by kahweol. Therefore, kahweol's fat-lowering effects are due to a reduction of food intake in C. elegans.

Anti-stress effects of polyphenols: animal models and human trials

Polyphenols, a category of plant compounds that contain multiple phenol structural units, are widely distributed throughout the plant kingdom and have multiple benefits for human health including anti-obesity, anti-hyperglycemic, and anti-hyperlipidemic effects. Additionally, polyphenols have recently gained attention for their anti-stress effects. In this review article, we summarize physiological responses against exposure to stressors and discuss biomarkers for exposure to stressors that are widely used in animal studies and human trials. We also review commonly used animal models for evaluating anti-stress effects. Finally, we discuss recent findings related to the anti-stress effects of polyphenols evaluated in animal models and human trials, and their putative mechanisms. These emerging data require further investigation in scientific studies and human trials to evaluate the anti-stress effects of polyphenols and their potential use for the prevention of stress-related health problems.