Eriocitrin ameliorates diet-induced hepatic steatosis with activation of mitochondrial biogenesis

Bifidobacterium bifidum 1007478 derived indole-3-lactic acid alleviates NASH via an aromatic hydrocarbon receptor-dependent pathway in zebrafish

AIMS

This study investigates the potential of Bifidobacterium bifidum 1007478 (BB478) and its metabolite indole-3-lactic acid (ILA) in alleviating non-alcoholic steatohepatitis (NASH) induced by a high-fat diet (HFD) and fructose exposure.

MATERIALS AND METHODS

A zebrafish model of NASH was established by exposure to HFD and fructose. BB478 was administered, and the effects on liver lipid accumulation, oxidative stress, and inflammation were assessed. ILA production by BB478 was confirmed, and its impact on hepatic lipogenesis and inflammatory pathways was evaluated. The involvement of the aromatic hydrocarbon receptor (AhR) was also examined using an AhR inhibitor.

KEY FINDINGS

BB478 supplementation inhibited lipid accumulation in the liver, reduced triglycerides (TG) and total cholesterol (TC), and mitigated oxidative stress, as evidenced by lower levels of reactive oxygen species (ROS) and malondialdehyde (MDA). ILA, produced by BB478, could alleviate the hepatic damage and fat deposition in liver. Mechanistically, it suppressed hepatic lipogenesis by downregulating lipogenesis-related genes, including sterol response element binding protein 1 (SREBP1) and fatty acid synthase (FASN). ILA also inhibited the expression of pro-inflammatory cytokines to suppress inflammation. The therapeutic effects of ILA were reversed by the AhR inhibitor, indicating that ILA's actions are AhR-dependent.

SIGNIFICANCE

These findings reveal the potential of ILA, produced by Bifidobacterium bifidum, as a therapeutic agent for NASH. The mechanistic insights into AhR-mediated effects provide a foundation for further exploration of ILA as a novel approach for managing liver diseases.

Antioxidant and In Vitro Hepatoprotective Activities of a Polyphenol-Rich Fraction from the Peel of Citrus lumia Risso (Rutaceae)

Citrus lumia Risso is an ancient, cultivated Mediterranean lime belonging to the Rutaceae family. It is a species extremely difficult to retrieve, but it is still found in some private gardens in certain regions of Southern Italy. Citrus fruits are a rich source of bioactive compounds, particularly polyphenols, which have been linked to a reduction in the risk of several metabolic diseases. Here, hesperidium peel extracts were obtained by maceration with ethanol:water mixtures in different proportions (50:50, 80:20, 0:100) and the resulting crude extracts were then passed through a glass column containing adsorbent resins to concentrate the polyphenolic compounds. After phytochemical characterization, the extracts were evaluated for antioxidant activity using electron paramagnetic resonance (EPR) spectroscopy. Finally, the water polyphenolic-rich extract (ClumWp), which was the extract with the highest flavonoid content (18.355 ± 1.607 mg/mL) and the strongest antioxidant activity against hydroxyl radical, was tested to evaluate its potential protective effects on lipid accumulation in both 2D hepatocyte cultures and 3D spheroids. Treatment with 25 and 50 μg/mL resulted in a reduction in intracellular lipid content in the HepG2 liver cell line, while treatment with 100 µg/mL ClumWp resulted in a reduction in the intracellular lipid content in HepG2 + LX2 spheroids. In addition, treatment with ClumWp significantly increased ATP levels in the spheroids compared to those untreated, suggesting its ability to restore and promote ATP production. Our results highlight that the study of neglected species, such as Citrus lumia Risso, remains a valuable opportunity to valorize Mediterranean biodiversity, especially in the context of its potential applications to improve human health. In particular, the polyphenolic fraction of Citrus lumia peel showed promising effects on lipid metabolism and cellular energy balance and may prove valuable in the treatment of metabolic disorders such as MASLD, where lipid accumulation disrupts normal cellular functions.

Eriocitrin ameliorates hepatic fibrosis and inflammation: The involvement of PPARα-mediated NLRP1/NLRC4 inflammasome signaling cascades

ETHNOPHARMACOLOGICAL RELEVANCE

Citri Reticulatae Pericarpium (Chenpi) is a traditional Chinese medicine and recorded to have hepatoprotective therapeutic and condition value. Eriocitrin (ER) a natural compound isolated from Citri Reticulatae Pericarpium may ameliorate hepatic inflammation in chronic liver diseases.

AIM OF THE STUDY

The current study investigates the hepatoprotective effect and potential mechanism of ER against hepatic fibrosis.

MATERIALS AND METHODS

The hepatic fibrosis mouse model was constructed by intraperitoneally injecting thioacetamide (TAA) for five weeks. Hepatic stellate cells (HSCs) were treated with transforming growth factor-β (TGF-β). Meanwhile, lipopolysaccharide/adenosine triphosphate (LPS/ATP) was given to excite the normal mouse bone marrow-derived macrophages (BMDMs), and thus the cells could acquire the conditioned medium. Moreover, LX-2 cells were administrated with PPARα knockdown vector (siRNA-PPARα).

RESULTS

RNA sequencing studies revealed that in mice induced by TAA, the PPARα/NOD-like receptor/neutrophil extracellular traps (NETs) significantly influence ER-based hepatic protection. In TAA-induced mice, ER could up-regulate PPARα and down-regulate NLRP1/NLRC4 and the development of NETs. Our findings indicated that ER significantly up-regulated PPARα, inhibited NLRP1/NLRC4 inflammasome in HSCs. Deficiency of PPARα in the activated LX-2 weakened the regulatory effect of ER on inhibiting the NLRP1/NLRC4 inflammasome. In addition, ER might hinder the activation of BMDMs and also obstruct IL-1β and IL-6 passage in the extracellular space.

CONCLUSIONS

The results indicated that ER decreased inflammation by controlling the PPARα-NLRP1/NLRC4 signaling pathway and inhibiting fibril formation. Collectively, our results underscore the therapeutic potential of ER in addressing hepatic fibrosis.

Bioprotective Role of Phytocompounds Against the Pathogenesis of Non-alcoholic Fatty Liver Disease to Non-alcoholic Steatohepatitis: Unravelling Underlying Molecular Mechanisms

Non-alcoholic fatty liver disease (NAFLD), with a global prevalence of 25%, continues to escalate, creating noteworthy concerns towards the global health burden. NAFLD causes triglycerides and free fatty acids to build up in the liver. The excessive fat build-up causes inflammation and damages the healthy hepatocytes, leading to non-alcoholic steatohepatitis (NASH). Dietary habits, obesity, insulin resistance, type 2 diabetes, and dyslipidemia influence NAFLD progression. The disease burden is complicated due to the paucity of therapeutic interventions. Obeticholic acid is the only approved therapeutic agent for NAFLD. With more scientific enterprise being directed towards the understanding of the underlying mechanisms of NAFLD, novel targets like lipid synthase, farnesoid X receptor signalling, peroxisome proliferator-activated receptors associated with inflammatory signalling, and hepatocellular injury have played a crucial role in the progression of NAFLD to NASH. Phytocompounds have shown promising results in modulating hepatic lipid metabolism and de novo lipogenesis, suggesting their possible role in managing NAFLD. This review discusses the ameliorative role of different classes of phytochemicals with molecular mechanisms in different cell lines and established animal models. These compounds may lead to the development of novel therapeutic strategies for NAFLD progression to NASH. This review also deliberates on phytomolecules undergoing clinical trials for effective management of NAFLD.

Eriocitrin prevents Sepsis-induced acute kidney injury through anti-inflammation and anti-oxidation via modulating Nrf2/DRP1/OPA1 signaling pathway

BACKGROUND

Severe inflammation and oxidative stress are characteristics of sepsis-associated kidney injury with high morbidity and mortality. Eriocitrin (ERI) has shown promise in suppressing sepsis-associated kidney injury and LPS-induced periodontal disease, however, its efficacy in alleviating SAKI remains unexplored. This study aimed to investigate the therapeutic potential of ERI on SAKI through in vivo and in vitro experiments, elucidating its underlying mechanism.

METHODS

The therapeutic effects of ERI against SAKI were evaluated by survival rate, changes of serum creatinine (Scr) and blood urea nitrogen (BUN) and statistic of renal histological score in a Cecal ligation and puncture (CLP)-induced septic mice. Impactions about anti-coagulation, anti-inflammation, anti-oxidative stress and improvement of mitochondrial damage and mitochondrial morphology were further assayed. In vitro, HUVECs upon stimulation of LPS with or without different dosage of ERI, followed by evaluating changes in inflammation, mitochondrial dynamic equilibrium and signaling pathways.

RESULTS

ERI demonstrated ameliorative effects on SAKI by attenuating inflammation, oxidative stress and coagulation evidenced by the improved survival rate, alleviated kidney histological injury, declined BUN and Scr in serum and diminished levels of inflammation cytokines, and coagulation factors. Mechanistically, ERI suppressed DRP1-regulated mitochondrial fission and promoted OPA1-modulated mitochondrial fusion by activating Nrf2 in septic mice and LPS-stimulated HUVECs, which maintained mitochondrial dynamic equilibrium, improved mitochondrial morphology, assured integrity of mitochondrial function, decreased oxidative stress, impeded overwhelming inflammation, and thus, played a pivotal role in ERI's protection against SAKI.

CONCLUSION

Our data confirmed the therapeutic potential of ERI in mitigating SAKI，suggesting its viability as a pharmacological agent in clinic settings.

Lemon Flavonoid Extract Eriomin Improves Pro/Antioxidant Status and Interferes with Cholesterol Metabolism without Affecting Serum Cholesterol Levels in Aged Rats

This study aimed to assess the antioxidant capacity of lemon flavonoid extract Eriomin® (LE) and its impact on cholesterol metabolism in the context of healthy aging. We orally treated 24-month-old male Wistar rats with an LE (40 mg/kg) suspended in 0.3 mL of sunflower oil. At the same time, control groups received an equal volume of sunflower oil (CON) or remained untreated (ICON) daily for 4 weeks. We examined LE's effects on superoxide dismutase and catalase- and glutathione-related enzyme activities, the concentration of lipid peroxides and protein carbonyls, total oxidant status (TOS) and antioxidant status (TAS), and oxidative stress index (OSI) in the liver, jejunum, and ileum. We also measured total cholesterol, its biosynthetic precursors (lanosterol, lathosterol, desmosterol), its degradation products (bile acid precursors) in the serum, liver, jejunum, and ileum, and serum phytosterols (intestinal absorption markers). LE reduced TOS, TAS, and OSI (p < 0.05) compared with control values, indicating its consistent antioxidant action in all examined organs. LE lowered hepatic desmosterol (p < 0.05) while also reducing 7α- and 24-hydroxycholesterol levels in the liver and ileum (p < 0.01). Serum cholesterol, hepatic gene expression, and the immunostaining intensity of CYP7A1 were unchanged. In conclusion, LE exerted non-enzymatic antioxidant effects and reduced cholesterol degradation, reducing its biosynthesis products, thereby maintaining serum cholesterol levels.

Transcription-related metabolic regulation in grafted lemon seedlings under magnesium deficiency stress

Magnesium is one of the essential nutrients for plant growth, and plays a pivotal role in plant development and metabolism. Soil magnesium deficiency is evident in citrus production, which ultimately leads to failure of normal plant growth and development, as well as decreased productivity. Citrus is mainly propagated by grafting, so it is necessary to fully understand the different regulatory mechanisms of rootstock and scion response to magnesium deficiency. Here, we characterized the differences in morphological alterations, physiological metabolism and differential gene expression between trifoliate orange rootstocks and lemon scions under normal and magnesium-deficient conditions, revealing the different responses of rootstocks and scions to magnesium deficiency. The transcriptomic data showed that differentially expressed genes were enriched in 14 and 4 metabolic pathways in leaves and roots, respectively, after magnesium deficiency treatment. And the magnesium transport-related genes MHX and MRS2 may respond to magnesium deficiency stress. In addition, magnesium deficiency may affect plant growth by affecting POD, SOD, and CAT enzyme activity, as well as altering the levels of hormones such as IAA, ABA, GA3, JA, and SA, and the expression of related responsive genes. In conclusion, our research suggests that the leaves of lemon grafted onto trifoliate orange were more significantly affected than the roots under magnesium-deficient conditions, further indicating that the metabolic imbalance of scion lemon leaves was more severe.

Scaffold Hopping and Screening for Potent Small Molecule Agonists for GRP94: Implications to Alleviate ER Stress-Associated Pathogenesis

Disparity in the activity of Endoplasmic reticulum (ER) leads to degenerative diseases, mainly associated with protein misfolding and aggregation leading to cellular dysfunction and damage, ultimately contributing to ER stress. ER stress activates the complex network of Unfolded Protein Response (UPR) signaling pathways mediated by transmembrane proteins IRE1, ATF6, and PERK. In addition to UPR, many ER chaperones have evolved to optimize the output of properly folded secretory and membrane proteins. Glucose-regulated protein 94 (GRP94), an ER chaperone of heat shock protein HSP90 family, directs protein folding through interaction with other components of the ER protein folding machinery and assists in ER-associated degradation (ERAD). Activation of GRP94 would increase the efficacy of protein folding machinery and regulate the UPR pathway toward homeostasis. The present study aims to screen for novel agonists for GRP94 based on Core hopping, pharmacophore hypothesis, 3D-QSAR, and virtual screening with small-molecule compound libraries in order to improve the efficiency of native protein folding by enhancing GRP94 chaperone activity, therefore to reduce protein misfolding and aggregation. In this study, we have employed the strategy of small molecule-dependent ER programming to enhance the chaperone activity of GRP94 through scaffold hopping-based screening approach to identify specific GRP94 agonists. New scaffolds generated by altering the cores of NECA, the known GRP94 agonist, were validated by employing pharmacophore hypothesis testing, 3D-QSAR modeling, and molecular dynamics simulations. This facilitated the identification of small molecules to improve the efficiency of native protein folding by enhancing GRP94 activity. High-throughput virtual screening of the selected pharmacophore hypothesis against Selleckchem and ZINC databases retrieved a total of 2,27,081 compounds. Further analysis on docking and ADMET properties revealed Epimedin A, Narcissoside, Eriocitrin 1,2,3,4,6-O-Pentagalloylglucose, Secoisolariciresinol diglucoside, ZINC92952357, ZINC67650204, and ZINC72457930 as potential lead molecules. The stability and interaction of these small molecules were far better than the known agonist, NECA indicating their efficacy in selectively alleviating ER stress-associated pathogenesis. These results substantiate the fact that small molecule-dependent ER reprogramming would activate the ER chaperones and therefore reduce the protein misfolding as well as aggregation associated with ER stress in order to restore cellular homeostasis.

Zebrafish facilitate non-alcoholic fatty liver disease research: Tools, models and applications

Non-alcoholic fatty liver disease (NAFLD) has become an increasingly epidemic metabolic disease worldwide. NAFLD can gradually deteriorate from simple liver steatosis, inflammation and fibrosis to liver cirrhosis and/or hepatocellular carcinoma. Zebrafish are vertebrate animal models that are genetically and metabolically conserved with mammals and have unique advantages such as high fecundity, rapid development ex utero and optical transparency. These features have rendered zebrafish an emerging model system for liver diseases and metabolic diseases favoured by many researchers in recent years. In the present review, we summarize a series of tools for zebrafish NAFLD research and the models established through different dietary feeding, hepatotoxic chemical treatments and genetic manipulations via transgenic or genome editing technologies. We also discuss how zebrafish models facilitate NAFLD studies by providing novel insights into NAFLD pathogenesis, toxicology research, and drug evaluation and discovery.

Eriocitrin attenuates sepsis-induced acute lung injury in mice by regulating MKP1/MAPK pathway mediated-glycolysis

Metabolic reprogramming has been shown to aggravate sepsis-induced acute lung injury. In particular, enhanced glycolysis is closely associated with inflammation and oxidative stress. Eriocitrin (ERI) is a natural flavonoid found in citrus fruit that exhibits various pharmacological activities, with antioxidant, anti-inflammatory, anti-diabetic, and anti-tumor properties. However, the role of ERI in lung injury is not well understood. We established a septic mouse model of acute lung injury (ALI) using lipopolysaccharide (LPS) for induction. Primary peritoneal macrophages were isolated to verify the relevant molecular mechanism. Tissues were assessed for lung pathology, pro-inflammatory cytokines, markers of oxidative stress, and protein and mRNA expression levels. In vivo experiments showed that ERI effectively alleviated LPS-induced pathological injury, suppress the inflammatory response (TNF-α, IL-1β, IL-6 levels) and decreased oxidative stress (MDA, ROS) in murine lung tissue. In vitro, ERI increased the resistance of LPS-treated cells to excessive inflammation and oxidative stress by inhibiting the enhancement of glycolysis (indicated by expression levels of HIF-1α, HK2, LDHA, PFKFB3, and PKM2). Specifically, the beneficial effects of ERI following LPS-induced lung injury occurred through promoting the expression of MKP1, which mediates the inactivation of the MAPK pathway to inhibit enhanced glycolysis. These results demonstrate that ERI has a protective effect on sepsis-induced ALI by regulating MKP1/MAPK pathway mediated-glycolysis. Hence, ERI is a promising candidate against ALI via inhibiting glycolysis.

In Vitro Antiglycation and Methylglyoxal Trapping Effect of Peppermint Leaf (Mentha × piperita L.) and Its Polyphenols

The most significant reactive α-dicarbonyl RCS involved in the pathomechanism of glycation and related diseases is methylglyoxal (MGO). Hyperglycemia promotes the generation of MGO and leads to the formation of advanced glycation end products (AGEs). Therefore, MGO trapping and glycation inhibition appear to be important therapeutic targets in prediabetes, diabetes, and in the early prevention of hyperglycemic complications. Peppermint leaf is commonly used as herbal tea, rich in polyphenols. Eriocitrin, its predominant component, in a double-blind, randomized controlled study reversed the prediabetic condition in patients. However, the antiglycation activity of this plant material and its polyphenols has not been characterized to date. Therefore, the aim of this study was to evaluate the ability of a peppermint leaf dry extract and its polyphenols to inhibit non-enzymatic protein glycation in a model with bovine serum albumin (BSA) and MGO as a glycation agent. Peppermint polyphenols were also evaluated for their potential to trap MGO in vitro, and the resulting adducts were analyzed by UHPLC-ESI-MS. To relate chemical composition to glycation inhibitory activity, the obtained peppermint extract was subjected to qualitative and quantitative analysis. The capability of peppermint leaf polyphenols to inhibit glycation (27.3-77.2%) and form adducts with MGO was confirmed. In the case of flavone aglycones, mono- and di-adducts with MGO were observed, while eriodictyol and eriocitrin effectively produced only mono-adducts. Rosmarinic acid and luteolin-7-O-glycosides did not reveal this action. IC₅₀ of the peppermint leaf dry extract was calculated at 2 mg/mL, equivalent to a concentration of 1.8 μM/mL of polyphenols, including ~1.4 μM/mL of flavonoids and ~0.4 μM/mL of phenolic acids. The contribution of the four major components to the anti-AGE activity of the extract was estimated at 86%, including eriocitrin 35.4%, rosmarinic acid 25.6%, luteolin-7-O-rutinoside 16.9%, luteolin-7-O-β-glucuronoside 8.1%, and others 14%. The effect of peppermint dry extract and polyphenols in inhibiting MGO-induced glycation in vitro was comparable to that of metformin used as a positive control.

Host-Guest Complexes HP-β-CD/Citrus Antioxidants: Exploratory Evaluations of Enhanced Properties in Biodegradable Film Packaging

The aim of this work was to exploit the antioxidant potential of molecules recovered during the pectin purification process of citrus lemon waste and to encapsulate them in stable pectin films, with a view to a green and circular economy process. Antioxidant molecules were recovered during the pectin purification process, further recovering matter from the waste. Seven molecules were identified and quantified, and the antioxidant power of the mixture and its stability over time was evaluated. To improve the stability of the bioactive fraction, this was complexed with 2-hydroxypropyl-β-cyclodextrin (HP-β-CD); indeed, this procedure increased their thermal stability from 120 °C up to 250 °C, as verified by thermogravimetry. Furthermore, the most promising complexes were studied under autoclave-like conditions (120 °C, 28 min) to simulate thermal sterilization. The antioxidants and HP-β-CD were combined in a pectin film, showing increased stability over time (up to three times) compared to uncomplexed antioxidants. This process represents a first step towards the development of applicable devices for the delivery of antioxidant molecules.

Subcritical water extraction of Gracilaria chorda abbreviates lipid accumulation and obesity-induced inflammation

Obesity-induced inflammation is crucial in the pathogenesis of insulin resistance and type 2 diabetes. In this study, we investigated the effects of the Gracilaria chorda (GC) on lipid accumulation and obesity-induced inflammatory changes or glucose homeostasis in cell models (3T3-L1 adipocytes and RAW 264.7 macrophages). Samples of GC were extracted using solvents (water, methanol, and ethanol) and subcritical water (SW) at different temperatures (90, 150, and 210°C). The total phenolic content of GCSW extract at 210°C (GCSW210) showed the highest content compared to others, and GCSW210 highly inhibited lipid accumulation and significantly reduced gene expressions of peroxisome proliferatoractivated receptor-γ, CCAAT/enhancer-binding protein-α, sterol regulatory element-binding protein-1c, and fatty acid synthase in 3T3-L1 adipocytes. In addition, GCSW210 effectively downregulated the pro-inflammatory cytokine regulator pathways in RAW 264.7 macrophages, including mitogen-activated protein kinase, signal transducers and activators of transcription and nuclear factor-κB. In co-culture of 3T3-L1 adipocytes and RAW 264.7 macrophages, GCSW210 significantly reduced nitric oxide production and interleukin-6 levels, and improved glucose uptake with dose-dependent manner. These findings suggest that GCSW210 improves glucose metabolism by attenuating obesity-induced inflammation in adipocytes, which may be used as a possible treatment option for managing obesity and associated metabolic disorders.

Inflammation and Obesity: The Pharmacological Role of Flavonoids in the Zebrafish Model

A Mediterranean-style diet is highly encouraged thanks to its healthy food pattern, which includes valuable nutraceuticals such as polyphenols. Among these, flavonoids are associated with relevant biological properties through which they prevent or fight the onset of several human pathologies. Globally, the enhanced incidence of overweight and obese people has caused a dramatic increase in comorbidities, raising the need to provide better therapies. Therefore, the development of sophisticated animal models of metabolic dysregulation has allowed for a deepening of knowledge on this subject. Recent advances in using zebrafish (Danio rerio) as model for metabolic disease have yielded fundamental insights into the potential anti-obesity effects of flavonoids. Chronic low-grade inflammation and immune system activation seem to characterize the pathogenesis of obesity; thus, their reduction might improve the lipid profile of obese patients or prevent the development of associated metabolic illnesses. In this review, we highlight the beneficial role of flavonoids on obesity and related diseases linked to their anti-inflammatory properties. In light of the summarized studies, we suggest that anti-inflammatory therapies could have a relevant place in the prevention and treatment of obesity and metabolic disorders.

Metabolism of eriocitrin in the gut and its regulation on gut microbiota in mice

Introduction

Eriocitrin, found in lemon fruit, has shown a wide range of biological properties. Herein, we investigated the intestinal metabolic profile of eriocitrin in colon, and the regulation of dietary intervention of eriocitrin on gut microbiota.

Methods

We performed ultra performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS), 16S rDNA gene sequencing and gas chromatography-mass (GC-MS) on colon contents from the eriocitrin group (n=6), and compared them with control participants (n=6).

Results

A total of 136 flavonoids were found in colon contents, including eriocitrin and its six metabolites (eriodictyol, homoeriodictyol, hesperetin, eriodictyol-3'-O-glucoside, hesperetin-7-O-glucoside and eriodictyol-7-O-(6″-O-galloyl) glucoside). Moreover, dietary intervention of eriocitrin significantly alters the beta diversity of the gut microbiota, the probiotics such as Lachnospiraceae_UCG_006 were significantly enriched, and the production of butyrate, valerate and hexanoate in the colon pool of short-chain fatty acids were significant increased. The spearman's association analysis performed some intestinal bacteria may be involved in the metabolism of eriocitrin.

Discussion

Collectively, our results preliminarily suggest the metabolism of eriocitrin in the gut, demonstrating alterations of eriocitrin in gut microbiota, which warrants further investigation to determine its potential use in food and biomedical applications.

The effects of an obesogenic diet on behavior and cognition in zebrafish (Danio rerio): Trait average, variability, repeatability, and behavioral syndromes

The obesity epidemic, largely driven by the accessibility of ultra-processed high-energy foods, is one of the most pressing public health challenges of the 21st century. Consequently, there is increasing concern about the impacts of diet-induced obesity on behavior and cognition. While research on this matter continues, to date, no study has explicitly investigated the effect of obesogenic diet on variance and covariance (correlation) in behavioral traits. Here, we examined how an obesogenic versus control diet impacts means and (co-)variances of traits associated with body condition, behavior, and cognition in a laboratory population of ~160 adult zebrafish (Danio rerio). Overall, an obesogenic diet increased variation in several zebrafish traits. Zebrafish on an obesogenic diet were significantly heavier and displayed higher body weight variability; fasting blood glucose levels were similar between control and treatment zebrafish. During behavioral assays, zebrafish on the obesogenic diet displayed more exploratory behavior and were less reactive to video stimuli with conspecifics during a personality test, but these significant differences were sex-specific. Zebrafish on an obesogenic diet also displayed repeatable responses in aversive learning tests whereas control zebrafish did not, suggesting an obesogenic diet resulted in more consistent, yet impaired, behavioral responses. Where behavioral syndromes existed (inter-class correlations between personality traits), they did not differ between obesogenic and control zebrafish groups. By integrating a multifaceted, holistic approach that incorporates components of (co-)variances, future studies will greatly benefit by quantifying neglected dimensions of obesogenic diets on behavioral changes.

Nutraceutical Eriocitrin (Eriomin) Reduces Hyperglycemia by Increasing Glucagon-Like Peptide 1 and Downregulates Systemic Inflammation: A Crossover-Randomized Clinical Trial

This double-blind, randomized, placebo/controlled, crossover study evaluated the efficacy of Eriomin^® in reducing hyperglycemia and improving diabetes-related biomarkers in individuals with hyperglycemia above 110 mg/dL (mean 123 ± 18 mg/dL). Subjects (n = 30), divided into two groups (Eriomin or Placebo), who received a dose of 200 mg/d of the designated supplement for 12 weeks and, after a washout period of 2 weeks, switched to the other supplement in the following 12 weeks. Assessments of biochemical, metabolic, inflammatory, blood pressure, anthropometry, and dietary parameters were performed at the beginning and end of each intervention. Treatment with 200 mg/d of Eriomin significantly decreased blood glucose (-5%), homeostasis model assessment of insulin resistance (-11%), glucagon (-13%), interleukin-6 (-14%), tumor necrosis factor alpha (-20%), and alkaline phosphatase (-13%); but increased glucagon-like peptide 1 (GLP-1) by (17%) (P ≤ .05). At the end of the placebo period, there was a 13% increase in triglycerides (P ≤ .05). Other parameters evaluated did not change with Eriomin or placebo. In conclusion, intervention with Eriomin benefited the glycemic control of prediabetic and diabetic patients, with higher blood glucose levels, by increasing GLP-1 and decreasing systemic inflammation.

Zebrafish: A New Promise to Study the Impact of Metabolic Disorders on the Brain

Zebrafish has become a popular model to study many physiological and pathophysiological processes in humans. In recent years, it has rapidly emerged in the study of metabolic disorders, namely, obesity and diabetes, as the regulatory mechanisms and metabolic pathways of glucose and lipid homeostasis are highly conserved between fish and mammals. Zebrafish is also widely used in the field of neurosciences to study brain plasticity and regenerative mechanisms due to the high maintenance and activity of neural stem cells during adulthood. Recently, a large body of evidence has established that metabolic disorders can alter brain homeostasis, leading to neuro-inflammation and oxidative stress and causing decreased neurogenesis. To date, these pathological metabolic conditions are also risk factors for the development of cognitive dysfunctions and neurodegenerative diseases. In this review, we first aim to describe the main metabolic models established in zebrafish to demonstrate their similarities with their respective mammalian/human counterparts. Then, in the second part, we report the impact of metabolic disorders (obesity and diabetes) on brain homeostasis with a particular focus on the blood-brain barrier, neuro-inflammation, oxidative stress, cognitive functions and brain plasticity. Finally, we propose interesting signaling pathways and regulatory mechanisms to be explored in order to better understand how metabolic disorders can negatively impact neural stem cell activity.

Zebrafish obesogenic test identifies anti-adipogenic fraction in Moringa oreifera leaf extracts

The zebrafish obesogenic test (ZOT) is a powerful tool for identifying anti-adipogenic compounds for in vivo screening. In our previous study, we found that Moringa oleifera (MO) leaf powder suppressed the accumulation of visceral adipose tissue (VAT) in ZOT. MO demonstrates a wide range of pharmacological effects; however, little is known about its functional constituents. To identify the anti-adipogenic components of MO leaves, we prepared extracts using different extraction methods and tested the obtained extracts and fractions using ZOT. We found that the dichloromethane extract and its hexane:EtOAc = 8:2 fraction reduced VAT accumulation in young zebrafish fed a high-fat diet. We also performed gene expression analysis in the zebrafish VAT and found that CCAAT/enhancer-binding protein beta and CCAAT/enhancer-binding protein delta (associated with early stages of adipogenesis) gene expression was downregulated after fraction 2 administration. We identified a new MO fraction that suppressed VAT accumulation by inhibiting early adipogenesis using the ZOT. Phenotype-driven zebrafish screening is a reasonable strategy for identifying bioactive components in natural products.

Mitochondrial Targeting Therapeutics: Promising Role of Natural Products in Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) has become one of the most common chronic liver diseases worldwide, and its prevalence is still growing rapidly. However, the efficient therapies for this liver disease are still limited. Mitochondrial dysfunction has been proven to be closely associated with NAFLD. The mitochondrial injury caused reactive oxygen species (ROS) production, and oxidative stress can aggravate the hepatic lipid accumulation, inflammation, and fibrosis. which contribute to the pathogenesis and progression of NAFLD. Therefore, pharmacological therapies that target mitochondria could be a promising way for the NAFLD intervention. Recently, natural products targeting mitochondria have been extensively studied and have shown promising pharmacological activity. In this review, the recent research progress on therapeutic effects of natural-product-derived compounds that target mitochondria and combat NAFLD was summarized, aiming to provide new potential therapeutic lead compounds and reference for the innovative drug development and clinical treatment of NAFLD.

Globin Digest Improves Visceral Adiposity Through UCP1 Upregulation in Diet-Induced Obese Zebrafish and Mice

Globin digest (GD), a bioactive oligopeptide derived from porcine hemoglobin proteins, has been demonstrated to have beneficial effects on improving postprandial hyperlipidemia, hyperglycemia, and liver injury. We previously reported the lipid-lowering effects of GD using a zebrafish obesogenic test. Here, we sought to evaluate the effect of GD on visceral adiposity and the underlying molecular mechanisms using zebrafish and mouse obesity models. GD ameliorated dyslipidemia and suppressed the accumulation of visceral adipose tissue (VAT) in adult obese zebrafish. Transcriptomic analysis by RNA sequencing of GD-treated adult zebrafish revealed that GD upregulated UCP1-related pathways. Further, we performed mouse experiments and found that GD intake (2 mg/g body weight/day) was associated with lowered plasma triglyceride and total cholesterol levels, decreased VAT accumulation, and improved adipocyte hypertrophy with the upregulation of Ucp1 expression in white adipose tissue at both the mRNA and protein levels. Taken together, these results indicate that GD improves visceral adiposity by upregulating UCP1 expression, providing a novel perspective on combating obesity.

Effect of Eriocitrin on Cell Proliferation, Apoptosis, Migration, and Scar Formation-Related Genes Expression in Tendon Stem Cells

Tendinopathy is a common disease in elite and recreational athletes, and Eriocitrin is a flavonoid compound, which has antioxidant properties. The present study was undertaken to investigate the effect of Eriocitrin on tendon stem cells in vitro. Different concentrations of Eriocitrin (0, 25, 50, 75 µM) were used to treat tendon stem cells, cell proliferation was determined by CCK8 assay, apoptosis was detected by propidium iodide (PI) staining assays and caspase-3 activity assessment, wound-healing assaywas selected to detect the migration, and RT-PCR was chosen to detect the expression levels of scar formation-related gene markers (COMP, Fibronectin, and Biglycan). Eriocitrin treatment promoted cell proliferation of tendon stem cells in dose-dependent manner, and it reduced the apoptotic activities and improved the migration of tendon stem cells. It inhibited COMP, Biglycan, and Fibronectin expression. In summary, eriocitrin promoted cell proliferation of tendon stem cells, improved the migration of tendon stem cells, and inhibited the expression levels of some scar formation-related gene markers.

Targeting Mitochondrial Biogenesis with Polyphenol Compounds

Appropriate mitochondrial physiology is an essential for health and survival. Cells have developed unique mechanisms to adapt to stress circumstances and changes in metabolic demands, by meditating mitochondrial function and number. In this context, sufficient mitochondrial biogenesis is necessary for efficient cell function and haemostasis, which is dependent on the regulation of ATP generation and maintenance of mitochondrial DNA (mtDNA). These procedures play a primary role in the processes of inflammation, aging, cancer, metabolic diseases, and neurodegeneration. Polyphenols have been considered as the main components of plants, fruits, and natural extracts with proven therapeutic effects during the time. These components regulate the intracellular pathways of mitochondrial biogenesis. Therefore, the current review is aimed at representing an updated review which determines the effects of different natural polyphenol compounds from various plant kingdoms on modulating signaling pathways of mitochondrial biogenesis that could be a promising alternative for the treatment of several disorders.

Obesity Causes Abrupt Changes in the Testicular Microbiota and Sperm Motility of Zebrafish

Background

Obesity is a recognized risk factor for low fertility and is becoming increasingly prevalent in many countries around the world. Obesity changes intestinal microbiota composition, causes inflammation of various organs, and also reduces sperm quality. Several microorganisms are present in the testis. However, whether obesity affects the changes of testicular microbiota and whether these changes are related to reduced fertility in obese men remain to be elucidated.

Methods

In the present study, a zebrafish obesity model was established by feeding with egg yolk powder. Sperm motility was measured by the Computer Assisted Sperm Analysis system, testicular microbial communities was assessed via 16s RNA sequencing, the immune response in zebrafish testis was quantified by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay, and the testicular tissue structure was detected by electron microscopy and hematoxylin–eosin staining.

Results

Compared with the control group, zebrafish sperm motility was dramatically reduced, the expression of testicular proinflammatory cytokines in the testes was upregulated, and the blood–testis barrier structure was disrupted in the obese group. In addition, testicular microbiome composition was clearly altered in the obese group.

Conclusion

Obesity alters testicular microbiota composition, and the reason behind the decreased sperm motility in obese zebrafish may be related to changes in the testicular microbial communities.

Zebrafish and Flavonoids: Adjuvants against Obesity

Obesity is a pathological condition, defined as an excessive accumulation of fat, primarily caused by an energy imbalance. The storage of excess energy in the form of triglycerides within the adipocyte leads to lipotoxicity and promotes the phenotypic switch in the M1/M2 macrophage. These changes induce the development of a chronic state of low-grade inflammation, subsequently generating obesity-related complications, commonly known as metabolic syndromes. Over the past decade, obesity has been studied in many animal models. However, due to its competitive aspects and unique characteristics, the use of zebrafish has begun to gain traction in experimental obesity research. To counteract obesity and its related comorbidities, several natural substances have been studied. One of those natural substances reported to have substantial biological effects on obesity are flavonoids. This review summarizes the results of studies that examined the effects of flavonoids on obesity and related diseases and the emergence of zebrafish as a model of diet-induced obesity.

Preventive Effects of Green Tea Extract against Obesity Development in Zebrafish

Various natural products (NPs) have been used to treat obesity and related diseases. However, the best way to fight obesity is preventive, with accurate body weight management through exercise, diet, or bioactive NPs to avoid obesity development. We demonstrated that green tea extract (GTE) is an anti-obesity NP using a zebrafish obesity model. Based on a hypothesis that GTE can prevent obesity, the objective of this study was to assess GTE's ability to attenuate obesity development. Juvenile zebrafish were pretreated with GTE for seven days before obesity induction via a high-fat diet; adult zebrafish were pretreated with GTE for two weeks before obesity induction by overfeeding. As a preventive intervention, GTE significantly decreased visceral adipose tissue accumulation in juveniles and ameliorated visceral adiposity and plasma triglyceride levels in adult zebrafish obesity models. RNA sequencing analysis was performed using liver tissues from adult obese zebrafish, with or without GTE administration, to investigate the underlying molecular mechanism. Transcriptome analysis revealed that preventive GTE treatment affects several pathways associated with anti-obesity regulation, including activation of STAT and downregulation of CEBP signaling pathways. In conclusion, GTE could be used as a preventive agent against obesity.

The role and mechanism of citrus flavonoids in cardiovascular diseases prevention and treatment

Cardiovascular diseases (CVDs) have been ranked as the leading cause of death in the world, whose global incidence is increasing year by year. Citrus, one of the most popular fruits in the world, is rich in flavonoids. Citrus flavonoids attract special attention due to a variety of biological activities, especially in the prevention and treatment of CVDs. The research progress of citrus flavonoids on CVDs have been constantly updated, but relatively fragmented, which needed to be systematically summarized. Hence, the recent research about citrus flavonoids and CVDs were reviewed, including the types and in vivo processes of citrus flavonoids, epidemiology study and mechanism on prevention and treatment of CVDs by citrus flavonoids. This review would provide a theoretical basis for the citrus flavonoids research and a new idea in the citrus industry development and application.

Zebrafish as a Useful Model to Study Oxidative Stress-Linked Disorders: Focus on Flavonoids

The zebrafish is considered one of the most versatile experimental animal models. The transparency of the embryos, the small size, the rapid development and the homology with higher vertebrates have made the zebrafish a valuable model also for drug screening. Its use is closely related for the determination of bioactivity, toxicity and off-target side effects of novel drug candidates, which also allows a thorough evaluation of new targets; thus, it may represent a suitable model for drug screening and the optimization of novel candidates. Flavonoids are polyphenolic compounds widely present in fruits, vegetables and cereals. Polyphenols are important for both plants and humans, considering their involvement in defense mechanisms, particularly against oxidative stress. They protect plants from biotic and abiotic stressors and prevent or treat oxidative-based human diseases. For these reasons, polyphenols are used as nutraceuticals, functional foods and supplements by the pharmaceutical industry. Therefore, the most relevant findings on zebrafish as a useful experimental model to study oxidative stress-linked disorders, focusing on the biological activities of flavonoids, are here summarized and reviewed.

Twelve-Week Mediterranean Diet Intervention Increases Citrus Bioflavonoid Levels and Reduces Inflammation in People with Type 2 Diabetes Mellitus

The benefits of a Mediterranean Diet (MedDiet) in the management of diabetes have been reported, but the contribution of polyphenol-rich citrus fruit has not been studied widely. Here, we report the sub-study findings of a previously conducted MedDiet intervention clinical trial in patients with type 2 diabetes mellitus (T2DM), where we aimed to measure the diet intervention effects on plasma citrus bioflavonoids levels and biomarkers of inflammation and oxidative stress. We analysed plasma samples from 19 (of original 27) participants with T2DM who were randomly assigned to consume the MedDiet intervention or their usual diet for 12 weeks and then crossed over to the alternate diet. Compared with baseline, MedDiet significantly increased levels of the citrus bioflavonoids naringin, hesperitin and hesperidin (by 60%, 58% and 39%, respectively, p < 0.05) and reduced plasma levels of the pro-inflammatory cytokine IL-6 (by 49%, p = 0.016). Oxidative stress marker 8-hydroxy-2'-deoxyguanosine (8-OHdG) decreased by 32.4% (p = 0.128). Usual diet did not induce these beneficial changes. The reduced inflammatory profile of T2DM participants may, in part, be attributed to the anti-inflammatory actions of citrus bioflavonoids. Together with indications of improved oxidative stress, these findings add to the scientific evidence base for beneficial consumption of citrus fruit in the MedDiet pattern.

Eriocitrin attenuates ischemia reperfusion-induced oxidative stress and inflammation in rats with acute kidney injury by regulating the dual-specificity phosphatase 14 (DUSP14)-mediated Nrf2 and nuclear factor-κB (NF-κB) pathways

Background

Ischemia reperfusion (IR)-induced acute kidney injury (AKI) is accompanied by increased inflammatory response and oxidative stress. Eriocitrin is a flavonoid that is mainly derived from lemon or citrate juice. It exhibits various pharmacological effects and is known to have antioxidant and anti-steatotic benefits. However, research on the effect of eriocitrin against IR-induced oxidative stress and inflammation in AKI is limited.

Methods

In this study, an OGD/R of HK-2 cell in vitro and rat model of AKI in vivo were constructed. Then the cell or rats were treated with eriocitrin at different doses (60, 30, 10 mg/kg). The levels of apoptotic were detected by flow cytometry. Inflammatory and oxidative stress factors in supernatant in vitro and tissue in vivo. Meanwhile, Western blot was used to detect the change of dual-specificity phosphatase 14 (DUSP14), Nrf2 and nuclear factor-κB (NF-κB).

Results

Eriocitrin attenuated apoptosis of the human renal tubular epithelial cell line HK-2 mediated by oxygen glucose deprivation/reperfusion via the repression of inflammation and oxidative stress in a dose-dependent manner. Eriocitrin also enhanced the levels of dual-specificity phosphatase 14 (DUSP14) and Nrf2, and decreased NF-κB phosphorylation. Furthermore, the in vivo experiments indicated that eriocitrin dose-dependently alleviated IR-induced AKI and apoptosis in rats. By elevating DUSP14, eriocitrin promoted the expression of Nrf2 and inactivated NF-κB, thereby downregulating inflammation and oxidative stress. Moreover, inhibiting DUSP14 expression with protein tyrosine phosphatase (PTP) inhibitor IV reversed the kidney-protective effects of Eriocitrin.

Conclusions

Eriocitrin protected IR-induced AKI by attenuating oxidative stress and inflammation via elevating DUSP14, thereby providing a theoretical basis for the treatment of IR-induced AKI.

Impact of citrus flavonoid supplementation on inflammation in lipopolysaccharide-induced periodontal disease in mice

In general, the consumption of flavonoid-rich foods may influence the control/dysregulation of the magnitude and duration of inflammation and oxidative stress, which are known to contribute to multiple pathologies. Information regarding the impact of citrus flavonoid dietary supplementation on periodontal disease is still scarce. Herein, we investigated whether a diet supplemented with eriocitrin and eriodictyol could alter the course of the inflammatory response associated with LPS-induced periodontal disease in mice. Sixty BALB/c mice received a standard diet or a diet supplemented with different concentrations of eriocitrin or eriodictyol. After 30 days of food supplementation, a solution containing LPS from Escherichia coli was injected into the gingival tissues three times per week for four weeks. Neutrophils, mononuclear cells and eosinophils were assessed using a severity analysis system in H&E-stained sections and modified picrosirius red. The activities of myeloperoxidase (MPO), a marker of granulocyte infiltration, and eosinophil peroxidase (EPO) were determined spectrophotometrically. The oxidative damage was determined by measuring the malondialdehyde (MDA) content and anti-oxidative activity through the assessment of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Interleukin (IL)-1β, TNF-α, and IL-10 were quantified by multiplex immunoassay. Periodontal inflammation was significantly inhibited by citrus flavonoid supplementation, including reduced flatness of the gingival epithelium and chronic and acute inflammatory cell infiltration, as well as loss of connective tissue in the gingival papillae. Both eriocitrin and eriodictyol inhibited gingival IL-1β and TNF-α and increased IL-10 secondary to periodontitis. Significant protection and decreased MPO and EPO activity were detected in the periodontal tissue of citrus flavonoid-treated animals. In comparison with the LPS group, SOD, CAT and GPx activities were increased, while the MDA content was reduced, indicating decreased oxidative damage. These results suggest that a diet supplemented with the citrus flavonoids eriocitrin or eriodictyol may aid in the prevention of periodontitis, representing a potential method to enhance local immunity and host defense.

Low doses of eriocitrin attenuate metabolic impairment of glucose and lipids in ongoing obesogenic diet in mice

Eriocitrin is a citrus flavonoid with a high capacity to reduce the oxidative stress related to metabolic disorders and obesity. We assessed the effects of low doses of eriocitrin on the oxidative stress, inflammation, and metabolism of glucose and lipids of high-fat diet (HFD)-fed obese mice. Fifty male C57BL/6J mice were randomly assigned into five groups (n 10). The mice were fed an HFD (45 % kcal from fat, i.e. lard) for 4 weeks for obesity induction. After this period, the mice continued receiving the same HFD, but supplemented with eriocitrin at 10, 25 or 100 mg/kg body weight (bw) for an additional 4 weeks. Control groups were fed with standard diet (10 % kcal of fat, i.e. soy oil) or with HFD without eriocitrin, for eight consecutive weeks. At the end of the study, mice supplemented with eriocitrin showed lower levels of blood serum glucose and blood and liver triacylglycerols (P < 0⋅05). There was also improved levels of insulin, HOMA-IR, total-cholesterol, resistin and lipid peroxidation in the supplemented mice. It was concluded that the 25 mg dose of eriocitrin improved all the parameters studied and had positive effects on oxidative stress, systemic inflammation and metabolism of lipids and glucose in general.

Eriocitrin Improves Adiposity and Related Metabolic Disorders in High-Fat Diet-Induced Obese Mice

Eriocitrin (EC) is an abundant flavonoid in lemons, which is known as a strong antioxidant agent. This study investigated the biological and molecular mechanisms underlying the anti-obesity effect of EC in high-fat diet (HFD)-fed obese mice. C57BL/6N mice were fed an HFD (40 kcal% fat) with or without 0.005% (w/w) EC for 16 weeks. Dietary EC improved adiposity by increasing adipocyte fatty acid (FA) oxidation, energy expenditure, and mRNA expression of thermogenesis-related genes in brown adipose tissue (BAT) and skeletal muscle, whereas it also decreased lipogenesis-related gene expression in white adipose tissue. In addition to adiposity, EC prevented hepatic steatosis by diminishing lipogenesis while enhancing FA oxidation in the liver and fecal lipid excretion, which was linked to attenuation of hyperlipidemia. Moreover, EC improved insulin sensitivity by decreasing hepatic gluconeogenesis and proinflammatory responses. These findings indicate that EC may protect against diet-induced adiposity and related metabolic disorders by controlling thermogenesis of BAT and skeletal muscle, FA oxidation, lipogenesis, fecal lipid excretion, glucose utilization, and gluconeogenesis.

Nephroprotective effects of eriocitrin via alleviation of oxidative stress and DNA damage against cisplatin-induced renal toxicity

Background

Cisplatin, a common anti-neoplastic drug used in the medical industry for cancer treatment has shown adverse nephrotoxic effects. This research targets to demonstrate the protective measure of eriocitrin, a bioactive flavonoid, against cisplatin-induced renal toxicity in rats.

Materials and methods

Rats of normal control and model groups were treated with saline whereas experimental groups received oral administration of eriocitrin (25 and 50 mg/kg b.w.) for 10 days and a single intraperitoneal (i.p.) injection of cisplatin (8 mg/kg b.w.) was given on the 7th day for all except normal control group. Blood serum, urine, and kidney tissue samples were collected for analysis.

Results

Cisplatin-induced rats demonstrated significant renal toxicity and damage. Eriocitrin dose-dependently reversed the effects by decreasing the proteinuria in urine, and urea, creatinine, lipid peroxidation, nitric oxide (NO) and pro-inflammatory cytokine levels (TNF-α, IL-1β) in serum. The tissue levels of reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were increased, whereas the levels of tissue DNA fragmentation and serum PARP-1 and Caspase-3 were reduced against model group. Histopathological modulations were supporting the protective effect of eriocitrin.

Conclusion

Eriocitrin has significant nephroprotective effects against cisplatin-induced renal toxicity by alleviating oxidative stress, preventing apoptosis and DNA damage.

Eriocitrin alleviates oxidative stress and inflammatory response in cerebral ischemia reperfusion rats by regulating phosphorylation levels of Nrf2/NQO-1/HO-1/NF-κB p65 proteins

Background

Cerebral ischemia (CI) can lead to ischemic stroke. The most effective therapy for cerebral ischemic stroke is the early restoration of blood reperfusion. However, reperfusion after CI can result in cerebral ischemia reperfusion (CI/R) injury. This study aimed to detect the effect of eriocitrin on cerebral I/R injury and investigate the underlying mechanism.

Methods

Seventy male Sprague-Dawley (SD) rats were randomly divided into 5 groups: the control group, the cerebral I/R group, the I/R + eriocitrin 8 mg/kg group, the I/R + eriocitrin 16 mg/kg group, and the I/R + eriocitrin 32 mg/kg group. Different doses of eriocitrin or 0.5% carboxymethyl cellulose sodium were administrated to the rats once daily for 7 days before middle cerebral artery occlusion (MCAO). PCR staining was performed to observe cerebral infarction. Hematoxylin and eosin (H&E) staining was carried out to observe the damage to the brain tissue. Terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) was used to detect apoptosis. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the relative mRNA levels of related molecules. Western blot was used to detect the expression of related proteins. The detection kits were used to detect superoxide dismutase (SOD) and lactic dehydrogenase (LDH) activity, and malondialdehyde (MDA) content respectively. Enzyme-linked immunosorbent assay (ELISA) was used to detect TNF-radiation, interleukin-6 (IL-6), and interleukin-10 (IL-10).

Results

The results showed that Eriocitrin significantly reduced the cerebral infarct volume, cerebral water content, and cerebral indexes. Eriocitrin treatment alleviated pathological injury, promoted cell proliferation, and inhibited cell apoptosis. Eriocitrin upregulated SOD activity and downregulated MDA and LDH content. Eriocitrin also effectively decreased the levels of IL-6 and tumor necrosis factor-α (TNF-α), but increased the content of IL-10 in serum and brain tissues. Furthermore, Eriocitrin increased the phosphorylation of nuclear factor erythroid 2-related factor (Nrf2), as well as the expressions of heme-oxygenase-1 (HO-1) and quinine oxidoreductase 1 (NQO1). Moreover, Eriocitrin decreased the phosphorylation of nuclear factor-κB (NF-κB) p65.

Conclusions

Our results indicated that Eriocitrin attenuated oxidative injury and inflammatory response in rats with CI/R via the Nrf2/HO-1/NQO1/NF-κB signaling pathway.

Antinociceptive Effect of the Citrus Flavonoid Eriocitrinon Postoperative Pain Conditions

BACKGROUND

Postoperative pain remains a major clinical problem as there are limited analgesic strategies that have been proven to be effective in preventing and relieving this type of pain. Natural products, including flavonoids, have distinct pharmacological properties and play an important role in the discovery of analgesic drugs.

MATERIALS AND METHODS

In this study, the flavonoid eriocitrin (eriodictyol 7-O-rutinoside), which is the main flavonoid in lemon fruit (Citrus limon), was mechanistically investigated for its prospective antinociceptive effect in a mouse model of postoperative pain. The antinociceptive property was evaluated by utilizing both tonic (acetic acid-induced writhing behavior) and phasic (hot-plate) nociception modalities. The hindpaw incisional surgery was performed and hyperalgesia was assessed using von Frey filaments.

RESULTS

The tested doses of eriocitrin significantly attenuated (P<0.01, P<0.001) the chemically-induced tonic visceral nociception (5, 10, 15, and 30 mg/kg) and acute phasic thermal nociception (10, 15, and 30 mg/kg). A significant dose-dependent reduction in the incisional nociceptive hyperalgesia was exhibited by eriocitrin, with a marked antinociception observed at doses of 15 mg/kg (P<0.05 during 30-60 minutes) and 30 mg/kg (P<0.05, P<0.01 during 30-120 minutes).

CONCLUSION

The antinociceptive effect of eriocitrin (30 mg/kg) was strongly blocked by the antagonists of the opioid receptor, naltrexone, and GABAA receptor, bicuculline, thereby suggesting the involvement of opioidergic and GABAergic mechanisms in the nociception, reducing proclivity of eriocitrin during transmission of incisional nociception. These results concluded that eriocitrin has a potent antinociceptive effect in postoperative pain conditions, probably mediated through opioid and GABAA receptors.

Quzhou Fructus Aurantii Extract suppresses inflammation via regulation of MAPK, NF-κB, and AMPK signaling pathway

The anti-inflammatory activity of Quzhou Fructus Aurantii Extract (QFAE) has been reported recently. Thus, present study aims to explore the mechanism of anti-inflammation of QFAE in vitro and in vivo to develop a lung phylactic agent. The anti-inflammatory mechanism of QFAE in RAW 264.7 cells and acute lung injury (ALI) mice model was determined by cytokines analysis, histopathological examination, Western blot assay, immunofluorescence, and immunohistochemistry analysis. The results showed that QFAE restrained mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways in LPS-induced RAW 264.7 cells, whereas AMP-activated protein kinase (AMPK) signaling pathways were activated, as revealed by prominent attenuation of phosphorylation of ERK, JNK, p38, p65, IκBα, RSK and MSK, and overt enhancement of phosphorylation of ACC and AMPKα. The levels of pro-inflammatory cytokines TNF, IL-6, and IL-1β were suppressed, whereas the level of anti-inflammatory cytokine IL-10 increased after pretreatment with QFAE in vivo and in vitro. Moreover, QFAE prevented mice from LPS-provoked ALI, bases on alleviating neutrophils, and macrophages in bronchoalveolar lavage fluid (BALF) and mitigatingpulmonary histological alters, as well as hematological change. The MAPK and NF-κB signaling pathways in LPS-stimulated ALI mice were dampened by QFAE pretreatment, whereas AMPK signaling pathways were accelerated, as testify by significant restraint of phosphorylation of ERK, JNK, p38, p65, and IκBα, and distinct elevation of phosphorylation of ACC and AMPKα. The remarkable anti-inflammatory effect of QFAE is associated with the suppression of MAPK and NF-κB signaling pathways and the initiation of AMPK signaling pathway.

Interaction of natural flavonoid eriocitrin with β-cyclodextrin and hydroxypropyl-β-cyclodextrin: an NMR and molecular dynamics investigation

Eriocitrin's binding to β-cyclodextrin and hydroxypropyl-β-cyclodextrin was elucidated using mono/bidimensional NMR experiments and all-atom MD (Glycam06).

The development and validation of an HPLC-MS/MS method for the determination of eriocitrin in rat plasma and its application to a pharmacokinetic study

Eriocitrin is one of the major active constituents of lemon fruit, and it possesses strong antioxidant, lipid-lowering, anticancer and anti-inflammatory activities and has long been used in food, beverages and wine.

Anti-inflammatory effects of eriocitrin against the dextran sulfate sodium-induced experimental colitis in murine model

Inflammatory bowel disease (IBD) is a continual ailment condition which engrosses the entire alimentary canal. The IBD can be primarily distinguished into two forms, ulcerative colitis, and Crohn's disease. The major symptoms of IBD include pustules or abscesses, severe abdominal pain, diarrhea, fistula, and stenosis, which may directly affect the patient's quality of life. A variety of mediators can stimulate the circumstances of IBD, some examples include infections by microbes such as bacteria, perturbation of the immune system and the surrounding environment of the intestines. Severe colitis was stimulated in the experimental animals through administering 4% dextran sulfate sodium (DSS) which is mixed in water ad libitum for 6 days. Eriocitrin (30 mg/kg) was then administered to the experimental animals followed by the induction of severe colitis to evaluate the therapeutic prospective of eriocitrin against the colon inflammation stimulated by DSS. In this study, eriocitrin (30 mg/kg) demonstrated significant (P < .05) attenuation activity against the DSS-stimulated severe colitis in experimental animals. Eriocitrin counteracted all of the clinical deleterious effects induced by DSS, such as body-weight loss, colon shortening, histopathological injury, accretion of infiltrated inflammatory cells at the inflamed region and the secretion of inflammatory cytokines. The results clearly showed that eriocitrin effectively attenuated DSS-induced acute colitis in experimental animals.

Adipose tissue as a possible therapeutic target for polyphenols: A case for Cyclopia extracts as anti-obesity nutraceuticals

Obesity is a significant contributor to increased morbidity and premature mortality due to increasing the risk of many chronic metabolic diseases such as type 2 diabetes, cardiovascular disease and certain types of cancer. Lifestyle modifications such as energy restriction and increased physical activity are highly effective first-line treatment strategies used in the management of obesity. However, adherence to these behavioral changes is poor, with an increased reliance on synthetic drugs, which unfortunately are plagued by adverse effects. The identification of new and safer anti-obesity agents is thus of significant interest. In recent years, plants and their phenolic constituents have attracted increased attention due to their health-promoting properties. Amongst these, Cyclopia, an endemic South African plant commonly consumed as a herbal tea (honeybush), has been shown to possess modulating properties against oxidative stress, hyperglycemia, and obesity. Likewise, several studies have reported that some of the major phenolic compounds present in Cyclopia spp. exhibit anti-obesity effects, particularly by targeting adipose tissue. These phenolic compounds belong to the xanthone, flavonoid and benzophenone classes. The aim of this review is to assess the potential of Cyclopia extracts as an anti-obesity nutraceutical as underpinned by in vitro and in vivo studies and the underlying cellular mechanisms and biological pathways regulated by their phenolic compounds.

[Next generation zebrafish-based drug discovery and precision medicine]

Even after entering the era of genomic drug discovery in the 21st century, development of a breakthrough therapeutic drug (first-in-class) for intractable diseases (unmet medical needs) has been extremely difficult, but to the US FDA 62% of the approved first-in-class drugs are found by phenotypic screening. The next-generation zebrafish drug discovery enables high-throughput quantitative live in vivo phenotypic screening, and has been impacting global drug discovery strategies now. Compared to severe immunodeficient mice, zebrafish is expected to become a true individualized medical tool as a clinical ex vivo diagnostic system because of the high efficiency and speed of engraftment of patient-derived cancer xenotransplantation. Phenomics-based personalized medicine with the patient-derived cancer xenograft zebrafish in addition to conventional omics platform of individualized medicine is a true next-generation precision medicine to utilize for selection of therapeutic drugs and decision of their doses for the patient, and emerging paradigm shift is realizing in this century.

Therapeutic Silencing of Centromere Protein X Ameliorates Hyperglycemia in Zebrafish and Mouse Models of Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is characterized by persistent hyperglycemia and is influenced by genetic and environmental factors. Optimum T2DM management involves early diagnosis and effective glucose-lowering therapies. Further research is warranted to improve our understanding of T2DM pathophysiology and reveal potential roles of genetic predisposition. We have previously developed an obesity-induced diabetic zebrafish model that shares common pathological pathways with humans and may be used to identify putative pharmacological targets of diabetes. Additionally, we have previously identified several candidate genes with altered expression in T2DM zebrafish. Here, we performed a small-scale zebrafish screening for these genes and discovered a new therapeutic target, centromere protein X (CENPX), which was further validated in a T2DM mouse model. In zebrafish, cenpx knockdown by morpholino or knockout by CRISPR/Cas9 system ameliorated overfeeding-induced hyperglycemia and upregulated insulin level. In T2DM mice, small-interfering RNA-mediated Cenpx knockdown decreased hyperglycemia and upregulated insulin synthesis in the pancreas. Gene expression analysis revealed insulin, mechanistic target of rapamycin, leptin, and insulin-like growth factor 1 pathway activation following Cenpx silencing in pancreas tissues. Thus, CENPX inhibition exerted antidiabetic effects via increased insulin expression and related pathways. Therefore, T2DM zebrafish may serve as a powerful tool in the discovery of new therapeutic gene targets.

Ability of prebiotic polysaccharides to activate a HIF1α-antimicrobial peptide axis determines liver injury risk in zebrafish

Natural polysaccharides have received much attention for their ability to ameliorate hepatic steatosis induced by high-fat diet. However, the potential risks of their use have been less investigated. Here, we show that the exopolysaccharides (EPS) from Lactobacillus rhamnosus GG (LGG) and L. casei BL23 reduce hepatic steatosis in zebrafish fed a high-fat diet, while BL23 EPS, but not LGG EPS, induce liver inflammation and injury. This is due to the fact that BL23 EPS induces gut microbial dysbiosis, while LGG EPS promotes microbial homeostasis. We find that LGG EPS, but not BL23 EPS, can directly activate intestinal HIF1α, and increased HIF1α boosts local antimicrobial peptide expression to facilitate microbial homeostasis, explaining the distinct compositions of LGG EPS- and BL23 EPS-associated microbiota. Finally, we find that liver injury risk is not confined to Lactobacillus-derived EPS but extends to other types of commonly used natural polysaccharides, depending on their HIF1α activation efficiency.

Effectiveness of Eriomin® in managing hyperglycemia and reversal of prediabetes condition: A double-blind, randomized, controlled study

This study evaluated the potential effectiveness of different doses of Eriomin® on hyperglycemia and insulin resistance associated with other metabolic biomarkers in prediabetic individuals. Prediabetes patients (n = 103, 49 ± 10 years) were randomly divided into four parallel groups: (a) Placebo; (b) Eriomin 200 mg; (c) Eriomin 400 mg; and (d) Eriomin 800 mg. Assessment of biochemical, metabolic, inflammatory, hepatic, renal, anthropometric markers, blood pressure, and dietary parameters were performed during 12 weeks of intervention. Treatment with all doses of Eriomin (200, 400, and 800 mg) had similar effects and altered significantly the following variables: blood glucose (−5%), insulin resistance (−7%), glucose intolerance (−7%), glycated hemoglobin (−2%), glucagon (−6.5%), C‐peptide (−5%), hsCRP (−12%), interleukin‐6 (−13%), TNFα (−11%), lipid peroxidation (−17%), systolic blood pressure (−8%), GLP‐1 (+15%), adiponectin (+19%), and antioxidant capacity (+6%). Eriomin or placebo did not influence the anthropometric and dietary variables. Short‐term intervention with Eriomin, at doses of 200, 400, or 800 mg/day, benefited glycemic control, reduced systemic inflammation and oxidative stress, and reversed the prediabetic condition in 24% of the evaluated patients.

Phenolic Breakdown Products of Cyanidin and Quercetin Contribute to Protection against Mitochondrial Impairment and Reactive Oxygen Species Generation in an In Vitro Model of Hepatocyte Steatosis

A question in cell culture and dietary studies on protection by flavonoids against conditions such as hepatocyte steatosis is whether effects might be due to phenolic breakdown/digestion products. In HepG2 hepatocytes, treatment with quercetin, cyanidin, or their phenolic breakdown/digestion products (protocatechuic acid, 2,4,6-trihydroxybenzaldehyde, and caffeic acid), starting 2 h prior to oleic acid for 24 h, protected similarly against increases in intracellular lipid and reactive oxygen species and decreased mitochondrial membrane potential. Cyanidin or the phenolic products also protected against decreased mitochondrial content. After preincubation for only 1 h (to limit spontaneous degradation) and removal prior to oleic acid, only the phenolic products protected against decreased mitochondrial content, and without adding oleic acid, only protocatechuic acid and caffeic acid, and less so cyanidin, induced mitochondrial content. The results suggest that phenolic breakdown/digestion products of cyanidin and quercetin contribute to the protective effects in vitro, and perhaps in vivo.

Effect of Post-Harvest LED and UV Light Irradiation on the Accumulation of Flavonoids and Limonoids in the Segments of Newhall Navel Oranges (Citrus sinensis Osbeck)

To investigate the effect of post-harvest light irradiation on the accumulation of flavonoids and limonoids, harvested Newhall navel oranges were continuously exposed to light-emitting diode (LED) and ultraviolet (UV) light irradiation for 6 days, and the composition and content of flavonoids and limonoids in the segments were determined using UPLC-qTOF-MS at 0, 6, and 15 days after harvest. In total, six polymethoxylated flavonoids (PMFs), five flavone-O/C-glycosides, seven flavanone-O-glycosides, and three limonoids were identified in the segments. The accumulation of these components was altered by light irradiation. Red and blue light resulted in higher levels of PMFs during exposure periods. The accumulation of PMFs was also significantly induced after white light, UVB and UVC irradiation were removed. Red and UVC irradiation induced the accumulation of flavone and flavanone glycosides throughout the entire experimental period. Single light induced limonoid accumulation during exposure periods, but limonoid levels decreased significantly when irradiation was removed. Principal component analysis showed a clear correlation between PMFs and white light, between flavonoid glycosides and red light and UVC, and between limonoids and UVC. These results suggest that the accumulation of flavonoids and limonoids in citrus is regulated by light irradiation. White light, red light and UVC irradiation might be a good potential method for improving the nutrition and flavor quality of post-harvest citrus.