Chicoric acid induces apoptosis in 3T3-L1 preadipocytes through ROS-mediated PI3K/Akt and MAPK signaling pathways

Cichoric acid improves isoproterenol-induced myocardial fibrosis via inhibition of HK1/NLRP3 inflammasome-mediated signaling pathways by reducing oxidative stress, inflammation, and apoptosis

Cichoric acid (CA), a natural phenolic compound found in many plants, has been reported to have antioxidant, anti-inflammatory, hypoglycemic, and other effects. The aim of this study was to determine the potential role and underlying mechanisms of CA in isoproterenol (ISO)-induced myocardial fibrosis (MF). The MF model was induced by subcutaneous ISO injection in mice. Blood and heart tissue were collected for examination. Hematoxylin and eosin staining and Masson's trichrome staining were used to evaluate the histopathological changes and collagen deposition. The production of reactive oxygen species markers was observed by fluorescence microscopy, the degree of cardiomyocyte microstructure injury was observed by transmission electron microscope, and oxidative stress factors were detected by kit method, and the effect of CA on inflammatory factors was detected by ELISA. The expression levels of collagen proteins and signaling pathways were further investigated by western blotting. The results showed that CA inhibited the expression of ISO-induced proinflammatory factors (TNF-α, IL-1β, and IL-18) and proteins (HK1, NLRP3, caspase-1, cleaved-caspase-1, and ASC), and regulated the expression of apoptotic factors (caspase-3, cleaved-caspase-3, Bax, and Bcl-2). The results indicated that CA may regulate the HK1/NLRP3 inflammasome pathway by inhibiting HK1 expression and play a protective role in MF.

Single-cell detection of DMSO promoted HL-60 differentiation toward granulocyte based on DC-iDEP for medicine screening

The most common form of leukemia in adults is acute leukemia. Drug differentiation control is an extremely critical treatment for acute leukemia. Unfortunately, current techniques detecting differentiation control experience long time and complex steps of verification hindering the pace of medicine discovery: flow cytometry and RT-PCR are highly accurate and efficient at a cost of inconvenient fluorescent labeling or a high risk of contamination; conventional staining leads to cell death unavailable for further pharmacological tests. There is a great interest in developing simple, fast, and non-invasive techniques to screen medicine. DC-iDEP is an emerging label-free identification technique taking advantage of the whole cell native biophysical property for sorting cell populations. Here, HL-60 cell line has been used as a model to study the differentiation process toward granulocytes and medicine efficacy. The results showed that DEP succeeded in detecting the DMSO promoted HL-60 differentiation degree by the weighted average characterization factor. This factor is related to the single cell biophysical property, which accumulates to generate differences in each population with distinct constitutions. Furthermore, cichoric acid was investigated to be capable of promoting DMSO-induced differentiation efficiently. Using the change induced by cichoric acid, the HL-60 medicine screening application has been first attempted based on DEP. A rapid, label-free medicine screening method has been established to monitor HL-60 differentiation toward granulocyte and has great potential for medicine screening.

Intermittent fasting promotes adipocyte mitochondrial fusion through Sirt3-mediated deacetylation of Mdh2

Fat deposition and lipid metabolism are closely related to the morphology, structure and function of mitochondria. The morphology of mitochondria between fusion and fission processes is mainly regulated by protein posttranslational modification. Intermittent fasting (IF) promotes high expression of Sirtuin 3 (Sirt3) and induces mitochondrial fusion in high-fat diet (HFD)-fed mice. However, the mechanism by which Sirt3 participates in mitochondrial protein acetylation during IF to regulate mitochondrial fusion and fission dynamics remains unclear. This article demonstrates that IF promotes mitochondrial fusion and improves mitochondrial function in HFD mouse inguinal white adipose tissue. Proteomic sequencing revealed that IF increased protein deacetylation levels in HFD mice and significantly increased Sirt3 mRNA and protein expression. After transfecting with Sirt3 overexpression or interference vectors into adipocytes, we found that Sirt3 promoted adipocyte mitochondrial fusion and improved mitochondrial function. Furthermore, Sirt3 regulates the JNK-FIS1 pathway by deacetylating malate dehydrogenase 2 (MDH2) to promote mitochondrial fusion. In summary, our study indicates that IF promotes mitochondrial fusion and improves mitochondrial function by upregulating the high expression of Sirt3 in HFD mice, promoting deacetylation of MDH2 and inhibiting the JNK-FIS1 pathway. This research provides theoretical support for studies related to energy limitation and animal lipid metabolism.

Chicoric Acid Presented NLRP3-Mediated Pyroptosis through Mitochondrial Damage by PDPK1 Ubiquitination in an Acute Lung Injury Model

Chicoric acid (CA), a functional food ingredient, is a caffeic acid derivative that is mainly found in lettuce, pulsatilla, and other natural plants. However, the anti-inflammatory effects of CA in acute lung injury (ALI) remain poorly understood. This study was conducted to investigate potential drug usage of CA for ALI and the underlying molecular mechanisms of inflammation. C57BL/6 mice were given injections of liposaccharide (LPS) to establish the in vivo model. Meanwhile, BMDM cells were stimulated with LPS+ATP to build the in vitro model. CA significantly alleviated inflammation and oxidative stress in both the in vivo and in vitro models of ALI through the inhibition of NLR family pyrin domain-containing 3 (NLRP3)-mediated pyroptosis. In addition, CA attenuated mitochondrial damage to suppress NLRP3-mediated pyroptosis in the in vivo and in vitro models of ALI by suppressing the production of reactive oxygen species (ROS) via inhibiting the Akt/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. CA inhibited the interaction between Akt at T308 and phosphoinositide-dependent kinase-1 (PDPK1) at S549, thus promoting the phosphorylation of the Akt protein. Furthermore, CA directly targeted the PDPK1 protein and accelerated PDPK1 ubiquitination, indicating that 91-GLY, 111-LYS, 126-TYR, 162-ALA, 205-ASP, and 223-ASP might be responsible for the interaction between PDPK1 and CA. In conclusion, CA from Lettuce alleviated NLRP3-mediated pyroptosis in the ALI model through ROS-induced mitochondrial damage by activating Akt/Nrf2 pathway via PDPK1 ubiquitination. The present study suggests that CA might be a potential therapeutic drug to treat or prevent ALI in pneumonia or COVID-19.

The effects and mechanisms of the anti-COVID-19 traditional Chinese medicine, Dehydroandrographolide from Andrographis paniculata (Burm.f.) Wall, on acute lung injury by the inhibition of NLRP3-mediated pyroptosis

BACKGROUND

Dehydroandrographolide (Deh) from Andrographis paniculata (Burm.f.) Wall has strong anti-inflammatory and antioxidant activities.

PURPOSE

To explore the role of Deh in acute lung injury (ALI) of coronavirus disease 19 (COVID-19) and its inflammatory molecular mechanism.

METHODS

Liposaccharide (LPS) was injected into a C57BL/6 mouse model of ALI, and LPS + adenosine triphosphate (ATP) was used to stimulate BMDMs in an in vitro model of ALI.

RESULTS

In an in vivo and in vitro model of ALI, Deh considerably reduced inflammation and oxidative stress by inhibiting NLRP3-mediated pyroptosis and attenuated mitochondrial damage to suppress NLRP3-mediated pyroptosis through the suppression of ROS production by inhibiting the Akt/Nrf2 pathway. Deh inhibited the interaction between Akt at T308 and PDPK1 at S549 to promote Akt protein phosphorylation. Deh directly targeted PDPK1 protein and accelerated PDPK1 ubiquitination. 91-GLY, 111-LYS, 126-TYR, 162-ALA, 205-ASP and 223-ASP may be the reason for the interaction between PDPK1 and Deh.

CONCLUSION

Deh from Andrographis paniculata (Burm.f.) Wall presented NLRP3-mediated pyroptosis in a model of ALI through ROS-induced mitochondrial damage through inhibition of the Akt/Nrf2 pathway by PDPK1 ubiquitination. Therefore, it can be concluded that Deh may be a potential therapeutic drug for the treatment of ALI in COVID-19 or other respiratory diseases.

Monacolin K Induces Apoptosis of Human Glioma U251 Cells by Triggering ROS-Mediated Oxidative Damage and Regulating MAPKs and NF-κB Pathways

Monacolin K (MK), a polyketo secondary metabolic compound of the mold genus Monascus, can promote the apoptosis of malignant cancer cells, possessing potential antitumor properties. However, its mechanism of action on gliomas remains unclear. Here, we explored and investigated the potential of the monacolin K's antitumor effect on human glioma U251 cells and its possible molecular mechanism. Results showed that the application of 10 μM monacolin K inhibited the proliferation of U251 cells, with an inhibitory rate of up to 53.4%. Additionally, monacolin K induced the generation of reactive oxygen species and activated mitochondria-mediated pathways, including decreased MMP, activation of caspase3/caspase9, decreased Na⁺/K⁺-ATPase and Ca²⁺-ATPase activities, and disruption of the antioxidant system, resulting in the disruption of intracellular reduction-oxidation homeostasis. Monacolin K also activated MAPK and NF-κB pathways, upregulating P38 activity and downregulating JNK/ERK/P65/IκBα expression, ultimately leading to apoptosis of U251 cells. Importantly, monacolin K was not cytotoxic to normal human cells, hUC-MSCs. We concluded that monacolin K can induce apoptosis in U251 cells by triggering ROS-mediated oxidative damage and regulating MAPKs and NF-κB pathways.

Chicoric acid attenuates tumor necrosis factor-α-induced inflammation and apoptosis via the Nrf2/HO-1, PI3K/AKT and NF-κB signaling pathways in C28/I2 cells and ameliorates the progression of osteoarthritis in a rat model

Osteoarthritis (OA) is the most common arthritis, and is characterized by inflammation and cartilage degradation. Chicoric acid (CA), a bioactive caffeic acid derivative isolated from the root of Taraxacum mongolicumHand. - Mazz., has been reported to have anti-inflammatory effects. However, the therapeutic effects of CA on chondrocyte inflammation remain unknown. Our study aimed to explore the effect of CA on OA both in vivo and in vitro. In vitro, CA treatment significantly suppressed the overproduction of nitric oxide (NO), prostaglandin E2 (PGE2), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and IL-12 in tumor necrosis factor alpha (TNF-α)-induced human C28/I2 chondrocytes. Moreover, CA attenuated TNF-α induced degradation of the extracellular matrix (ECM) by upregulating the expression of collagen Ⅱ and aggrecan, and downregulating ADAMTS-5 and matrix metalloproteinases (MMPs). Additionally, CA treatment inhibited apoptosis in C28/I2 cells by upregulating of Bcl-2 levels, downregulating Bax and ROS levels, and activating the Nrf2/HO-1 pathway. Mechanistically, CA exerted an anti-inflammatory effect by inhibiting the PI3K/AKT and NF-κB signaling pathways, enhancing Nrf-2/HO-1 to limit the activation of NF-κB. In vivo experiments also proved the therapeutic effects of CA on OA in rats. These findings indicate that CA may become a new drug for the treatment of OA.

Preparation, Characterization, and In Vitro Release of Curcumin-Loaded IRMOF-10 Nanoparticles and Investigation of Their Pro-Apoptotic Effects on Human Hepatoma HepG2 Cells

Curcumin (CUR) has a bright future in the treatment of cancer as a natural active ingredient with great potential. However, curcumin has a low solubility, which limits its clinical application. In this study, IRMOF-10 was created by the direct addition of triethylamine, CUR was loaded into IRMOF-10 using the solvent adsorption method, and the two were characterized using a scanning electron microscope (SEM), X-ray diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG) methods, and Brunauer–Emmett–Teller (BET) analysis. We also used the MTT method, 4′,6-diamidino-2-phenylindole (DAPI) staining, the annexin V/PI method, cellular uptake, reactive oxygen species (ROS), and the mitochondrial membrane potential (MMP) to perform a safety analysis and anticancer activity study of IRMOF-10 and CUR@IRMOF-10 on HepG2 cells. Our results showed that CUR@IRMOF-10 had a CUR load of 63.96%, with an obvious slow-release phenomenon. The CUR levels released under different conditions at 60 h were 33.58% (pH 7.4) and 31.86% (pH 5.5). Cell experiments proved that IRMOF-10 was biologically safe and could promote curcumin entering the nucleus, causing a series of reactions, such as an increase in reactive oxygen species and a decrease in the mitochondrial membrane potential, thereby leading to cell apoptosis. In summary, IRMOF-10 is an excellent drug carrier and CUR@IRMOF-10 is an effective anti-liver cancer sustained-release preparation.

Antimicrobial Terpenes Suppressed the Infection Process of Phytophthora in Fennel-Pepper Intercropping System

The interactions between non-host roots and pathogens may be key to the inhibition of soilborne pathogens in intercropping systems. Fennel (Foeniculum vulgare) can be intercropped with a wide range of other plants to inhibit soilborne pathogens in biodiversity cultivation. However, the key compounds of fennel root exudates involved in the interactions between fennel roots and pathogens are still unknown. Here, a greenhouse experiment confirmed that intercropping with fennel suppressed pepper (Capsicum annuum) blight disease caused by Phytophthora capsici. Experimentally, the roots and root exudates of fennel can effectively interfere with the infection process of P. capsici at rhizosphere soil concentrations by attracting zoospores and inhibiting the motility of the zoospores and germination of the cystospores. Five terpene compounds (D-limonene, estragole, anethole, gamma-terpenes, and beta-myrcene) that were identified in the fennel rhizosphere soil and root exudates were found to interfere with P. capsica infection. D-limonene was associated with positive chemotaxis with zoospores, and a mixture of the five terpene compounds showed a strong synergistic effect on the infection process of P. capsici, especially for zoospore rupture. Furthermore, the five terpene compounds can induce the accumulation of reactive oxygen species (ROS), especially anethole, in hyphae. ROS accumulation may be one of the antimicrobial mechanisms of terpene compounds. Above all, we proposed that terpene compounds secreted from fennel root play a key role in Phytophthora disease suppression in this intercropping system.

Activation of TLR4 induces severe acute pancreatitis-associated spleen injury via ROS-disrupted mitophagy pathway

Severe acute pancreatitis (SAP) is complicated by systemic inflammatory response syndrome and multiple organ dysfunction, the disease will eventually result in death in almost half of the case. The spleen, as the largest immune organ adjacent to the pancreas, is prone to damage in SAP, thereby aggravating the damage of other organs and increasing mortality. However, to date, the research on the mechanism and treatment of spleen injury caused by SAP is still in its infancy. Herein, we investigated the mechanism of spleen injury, and explored the application potential of tuftsin for relieving spleen damage in SAP mice. Firstly, SAP mice model was constructed via the retrograde infusion of 3.5 % sodium taurocholate into the biliopancreatic duct. Then, we proved that the up-regulation of Toll-like receptor 4 (TLR4) in spleen would lead to the accumulation of reactive oxygen species (ROS) and mitochondrial dysfunction under SAP conditions. The splenic ROS and mitochondrial dysfunction could be improved by N-acetylcysteine (NAC) treatment or knocking out TLR4 in SAP mice. Meanwhile, we found that NAC treatment could also improve the autophagy of spleen tissue, suggesting that splenic ROS may affect impaired autophagy, causing the accumulation of damaged mitochondria, aggravating spleen damage. Furthermore, we verified the mechanism of spleen injury is caused by splenic ROS affecting PI3K/p-AKT/mTOR pathway-mediated autophagy. In addition, we detected the spleen injury caused by SAP could decrease the concentration of tuftsin in the serum of mice. Whereas, exogenous supplementation of tuftsin ameliorated the pathological damage, ROS accumulation, impaired autophagy, inflammation expression and apoptosis in damaged spleen. In summary, we verified the new mechanism of SAP-caused spleen damage that TLR4-induced ROS provoked mitophagy impairment and mitochondrial dysfunction in spleen via PI3K/p-AKT mTOR signaling, and the application potential of tuftsin in treating spleen injury, which might expand novel ideas and methods for the treatment of pancreatitis.

First Insight into Nutraceutical Properties of Local Salento Cichorium intybus Varieties: NMR-Based Metabolomic Approach

BACKGROUND

Plants of genus Cichorium are known for their therapeutic and nutraceutical properties determined by a wealth of phytochemical substances contained in the whole plant. The aim of this paper was to characterize the metabolic profiles of local Salento chicory (Cichorium intybus L.) varieties ("Bianca", "Galatina", "Leccese", and "Otranto") in order to describe their metabolites composition together with possible bioactivity and health beneficial properties.

METHODS

The investigation was performed by 1H-NMR spectroscopy and Multivariate Analysis (MVA), by which the metabolic profiles of the samples were easily obtained and compared.

RESULTS

The supervised Partial Least Squares Discriminant Analysis (PLS-DA) analysis showed as "Bianca" and "Galatina" samples grouped together separated by "Leccese" and "Otranto" varieties. A different content of free amino acids and organic acids was observed among the varieties. In particular a high content of cichoric and monocaffeoyl tartaric acid was observed for the "Leccese" variety. The presence of secondary metabolites adds significant interest in the investigation of Cichorium inthybus, as this vegetable may benefit human health when incorporated into the diet.

CONCLUSIONS

The 1H-NMR (Nuclear Magnetic Resonance Spectroscopy) based characterization of Salento chicory varieties allowed us to determine the potential usefulness and nutraceutical properties of the product, also providing a method to guarantee its authenticity on a molecular scale.

Methylated Metabolites of Chicoric Acid Ameliorate Hydrogen Peroxide (H2O2)-Induced Oxidative Stress in HepG2 Cells

Chicoric acid (CA) can display health benefits as a dietary polyphenol. However, as CA is widely metabolized in vivo, the actual compounds responsible for its bioactivities are not entirely known. Herein, the major methylated metabolites of CA were isolated from an in vitro co-incubation system, and their structures were elucidated. The antioxidant activities of the monomethylated metabolites (M1) and dimethylated metabolites (M2) of CA were evaluated against H₂O₂-induced oxidative stress damage in HepG2 cells and compared to CA. The results indicated that both M1 and M2 had better antioxidant capacities than CA by increasing cell viability, improving mitochondrial function, and balancing cellular redox status. These compounds also prevented oxidative stress by mediating the Keap1/Nrf2 transcriptional pathway and downregulating enzyme activity. The current research indicates that the methylated metabolites of CA could potentially be the candidates that are responsible for the biological efficacies attributed to CA.

Aqueous Cichorium intybus L. seed extract may protect against acute palmitate-induced impairment in cultured human umbilical vein endothelial cells by adjusting the Akt/eNOS pathway, ROS: NO ratio and ET-1 concentration

Background

Endothelial dysfunction, which is a vascular response to oxidative stress and inflammation, involves a cascade of downstream events that lead to decreased synthesis of insulin-mediated vasodilator nitric oxide (NO) and increased production of vasoconstrictor protein endothelin-1 (ET-1). NO, and ET-1 production by endothelial cells is regulated by phosphatidylinositol 3-kinase (PI3K)-Akt-eNOS axis and mitogen-activated protein kinase (MAPK) axis of the insulin signaling pathway, respectively.

Methods

After treating the human umbilical vein endothelial cells (HUVECs) with either palmitate complexed with bovine serum albumin (BSA) (abbreviated as PA) or the aqueous Cichorium intybus L. (chicory) seed extract (chicory seed extract, abbreviated as CSE) alone, and simultaneously together (PA + CSE), for 3, 12, and 24 h, we evaluated the capacity of CSE to reestablish the PA-induced imbalance between PI3K/Akt/eNOS and MAPK signaling pathways. The level of oxidative stress was determined by fluorimeter. Insulin-induced levels of NO and ET-1 were measured by Griess and ELISA methods, respectively. Western blotting was used to determine the extent of Akt and eNOS phosphorylation.

Results

Contrary to PA that caused an increase in the reactive oxygen species (ROS) levels and attenuated NO production, CSE readjusted the NO/ROS ratio within 12 h. CSE improved the metabolic arm of the insulin signaling pathway by up-regulating the insulin-stimulated phospho-eNOS Ser1177/total eNOS and phospho-Akt Thr308/total Akt ratios and decreased ET-1 levels.

Conclusions

CSE ameliorated the PA-induced endothelial dysfunction not only by its anti-ROS property but also by selectively enhancing the protective arm and diminishing the injurious arm of insulin signaling pathways.

Molecular mechanism of down-regulating adipogenic transcription factors in 3T3-L1 adipocyte cells by bioactive anti-adipogenic compounds

Obesity is growing at an alarming rate, which is characterized by increased adipose tissue. It increases the probability of many health complications, such as diabetes, arthritis, cardiac disease, and cancer. In modern society, with a growing population of obese patients, several individuals have increased insulin resistance. Herbal medicines are known as the oldest method of health care treatment for obesity-related secondary health issues. Several traditional medicinal plants and their effective phytoconstituents have shown anti-diabetic and anti-adipogenic activity. Adipose tissue is a major site for lipid accumulation as well as the whole-body insulin sensitivity region. 3T3-L1 cell line model can achieve adipogenesis. Adipocyte characteristics features such as expression of adipocyte markers and aggregation of lipids are chemically induced in the 3T3-L1 fibroblast cell line. Differentiation of 3T3-L1 is an efficient and convenient way to obtain adipocyte like cells in experimental studies. Peroxisome proliferation activated receptor γ (PPARγ) and Cytosine-Cytosine-Adenosine-Adenosine-Thymidine/Enhancer-binding protein α (CCAAT/Enhancer-binding protein α or C/EBPα) are considered to be regulating adipogenesis at the early stage, while adiponectin and fatty acid synthase (FAS) is responsible for the mature adipocyte formation. Excess accumulation of these adipose tissues and lipids leads to obesity. Thus, investigating adipose tissue development and the underlying molecular mechanism is important in the therapeutical approach. This review describes the cellular mechanism of 3T3-L1 fibroblast cells on potential anti-adipogenic herbal bioactive compounds.

Apoptosis induction activity of polysaccharide from Lentinus edodes in H22-bearing mice through ROS-mediated mitochondrial pathway and inhibition of tubulin polymerization

Background

Lentinus edodes is a medicinal mushroom widely used in Asian countries for protecting people against some types of cancer and other diseases.

Objective

The objective of the present study was to investigate the direct antiproliferation activity and the antitumor mechanisms of water-extracted polysaccharide (WEP1) purified from L. edodes in H22 cells and H22-bearing mice.

Design

The extraction, isolation, purification, and structure determination of the water-soluted L. edodes polysaccharide WEP1 were performed. The growth inhibitory effects of WEP1 on H22 cells and H22-bearing mice were determined by 3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide (MTT) method and animal studies. Flow cytometry, scanning electron microscopy, and laser scanning confocal microscopy were used to observe the morphological characteristics of apoptotic cells. The levels of intracellular reactive oxygen species (ROS) were detected by flow cytometry using 2',7'-dichlorofluorescein-3',6'-diacetate (DCFH-DA). Western blot was used to determine the expressions of cell cycle proteins and apoptosis-related proteins.

Results

Results showed that WEP1 with a molecular weight of 662.1 kDa exhibited direct antiproliferation activity on H22 cells in a dose-dependent manner. In vivo, WEP1 significantly inhibited the growth of tumor at different doses (50, 100, and 200 mg/kg) and the inhibition rates were 28.27, 35.17, and 51.72%, respectively. Furthermore, morphological changes of apoptosis and ROS overproduction were observed in H22 cells by WEP1 treatment. Cell cycle assay and western blot analyses indicated that the apoptosis induction activity of WEP1 was associated with arresting cell cycle at G2/M phase and activating mitochondrial-apoptotic pathway. Besides, WEP1 disrupted the microtubule network accompanied by alteration of cellular morphology.

Conclusion

Results suggested that the antitumor mechanisms of WEP1 might be related to arresting cell cycle at G2/M phase, inhibiting tubulin polymerization and inducing mitochondrial apoptosis. Therefore, WEP1 possibly could be used as a promising functional food for preventing or treating liver cancer.

(-)-Hydroxycitric Acid Alleviates Oleic Acid-Induced Steatosis, Oxidative Stress, and Inflammation in Primary Chicken Hepatocytes by Regulating AMP-Activated Protein Kinase-Mediated Reactive Oxygen Species Levels

Nonalcoholic fatty liver disease (NAFLD) is one of the most complex liver diseases in the world, which is characterized by hepatic steatosis, oxidative stress, inflammation, and apoptosis. (-)-Hydroxycitric acid [(-)-HCA] can regulate obesity in different animals, while whether this beneficial effect of (-)-HCA can alleviate the NAFLD and its mechanism is unclear. Hence, this study aimed to determine the potential actions and mechanisms of (-)-HCA on NAFLD in oleic acid (OA)-induced hepatocytes. We found that (-)-HCA effectively improved OA-induced hepatic steatosis by regulating the expression level of fat metabolism key factors, which was achieved by activating AMP-activated protein kinase (AMPK) signaling in hepatocytes. Importantly, activated AMPK alleviates mitochondrial disorder via the peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α)-nuclear transcription factor 1 (NRF-1)-mitochondrial transcription factor A (TFAM) pathway, then reduces reactive oxygen species production, and blocks the activation of p38 MAPK-NF-κB pathway in OA-induced hepatocytes. These results not only provide a theoretical basis for the occurrence and development of NAFLD but also offer compelling evidence for prevention of NAFLD supplemental with (-)-HCA.

18β-Glycyrrhetinic acid induces human HaCaT keratinocytes apoptosis through ROS-mediated PI3K-Akt signaling pathway and ameliorates IMQ-induced psoriasis-like skin lesions in mice

Background

Psoriasis is a chronic inflammatory skin disease affecting 2–3% of the population worldwide. Hyperproliferative keratinocytes were thought to be an amplifier of inflammatory response, thereby sustaining persistence of psoriasis lesions. Agents with the ability to inhibit keratinocyte proliferation or induce apoptosis are potentially useful for psoriasis treatment. 18β-Glycyrrhetinic acid (GA), an active metabolite of glycyrrhizin, exhibits diverse pharmacological activities, including anti-inflammatory, anti-bacteria and anti-proliferation. The current study aims to evaluate the effects of GA on the proliferation and apoptosis of human HaCaT keratinocytes in vitro and investigate the effects of GA on the skin lesions of imiquimod (IMQ)-induced psoriasis-like mouse model in vivo.

Methods

Cell viability was assayed by CCK-8. Flow cytometry was performed to measure apoptosis and reactive oxygen species (ROS), with Annexin V-FITC/PI detection kit and DCFH-DA probe respectively. Caspase 9/3 activities were measured using caspase activity assay kits. The protein levels of Akt and p-Akt were determined using Western blotting. IMQ was applied to induce psoriasis-like skin lesions in mice. The histological change in mouse skin lesions was detected using hematoxylin and eosin (H&E) staining. The severity of skin lesions was scored based on Psoriasis Area Severity Index (PASI). RT-PCR was employed to examine the relative expression of TNF-α, IL-22 and IL-17A in mouse skin lesions.

Results

GA decreased HaCaT keratinocytes viability and induced cell apoptosis in a dose-dependent manner. In the presence of GA, intracellular ROS levels were significantly elevated. NAC, a ROS inhibitor, attenuated GA-mediated HaCaT keratinocytes growth inhibition and apoptosis. In addition, GA treatment remarkably decreased p-Akt protein level, which could be restored partially when cells were co-treated with GA and NAC. LY294002 (a PI3K inhibitor) treatment significantly enhanced GA-mediated cytotoxicity. Moreover, GA ameliorated IMQ-induced psoriasis-like skin lesions in mice.

Conclusions

GA inhibits proliferation and induces apoptosis in HaCaT keratinocytes through ROS-mediated inhibition of PI3K-Akt signaling pathway, and ameliorates IMQ-induced psoriasis-like skin lesions in mice.

Silencing of soluble epoxide hydrolase 2 gene reduces H2O2-induced oxidative damage in rat intestinal epithelial IEC-6 cells via activating PI3K/Akt/GSK3β signaling pathway

Oxidative stress plays a vital role in the occurrence and development of intestinal injury. Soluble epoxide hydrolase 2 gene (EPHX2) is a class of hydrolytic enzymes. We aim to explore the effects and molecular mechanism of siEPHX2 on H2O2-induced oxidative damage in rat intestinal epithelial IEC-6 cells. IEC-6 cells were transfected with EPHX2-siRNA and control si RNA plasmids by lipofectamine™ 2000 transfection reagent. The transfected samples were treated with H2O2 (50, 100, 200, 300, 400, and 500 µmol/L) for 12, 24, and 48 h, respectively. Cell viability was determined by cell counting kit-8 (CCK-8). Lactate dehydrogenase (LDH), malondialdehyde (MDA), and superoxide dismutase (SOD) were assessed by respective detection kits. Mitochondrial membrane potential (MMP), cell apoptosis and reactive oxygen species (ROS) and the levels of factors were determined by flow cytometer, quantitative real-time PCR (qRT-PCR) and western blot assays, respectively. We found that the IC50 of H2O2 was 200 µmol/L at 24 h, and the transfection of siEHPX2 in H2O2-induced IEC-6 cells significantly promoted the cell viability, SOD activity and MMP rate, and reduced the rates of ROS and apoptosis as well as LDH and MDA contents. siEHPX2 up-regulated the B-cell lymphoma-2 (Bcl-2) level and down-regulated the levels of fibroblast-associated (Fas), Fas ligand (Fasl), Bcl-2 associated X protein (Bax), and Caspase-3. Moreover, the phosphorylation levels of phosphoinositide 3 kinase (PI3K), protein kinase B (Akt), and glycogen synthase kinase3β (GSK3β) were up-regulated. We proved that siEPHX2 had a protective effect on H2O2-induced oxidative damage in IEC-6 cells through activating PI3K/Akt/GSK3β signaling pathway.

Chicoric acid improves neuron survival against inflammation by promoting mitochondrial function and energy metabolism

Chicoric acid (CA), a major nutraceutical component of a typical Mediterranean vegetable, chicory, possesses excellent antioxidant and anti-inflammatory bioactivities. This work aimed to elucidate the effects of CA on neuron survival against inflammation and the underlying molecular mechanisms. Results demonstrated that CA promoted SH-SY5Y cells' autophagic vesicle formation, up-regulated autophagic elongation phase related gene expressions, and inhibited apoptosis stimulated by microglial conditioned culture medium (MCM). In addition, CA significantly improved mitochondrial function and regulated redox homeostasis related signaling pathways such as MAPKs and PI3K/AKT. MCM with CA notably increased the expressions of PGC-1α, SIRT1 and enhanced the phosphorylation of AMPK, promoting energy metabolism. On the other hand, the underlying mechanisms of the intervention of CA in MCM-induced cell apoptosis were partly due to its direct protective effect on SH-SY5Y cells and inhibition of microglial inflammatory factor release. This establishes a theoretical foundation for neuro-nutrition intervention studies of natural functional food components, and provides new clues for developing health foods containing CA.

Chicoric acid (CA) induces autophagy in gastric cancer through promoting endoplasmic reticulum (ER) stress regulated by AMPK

Gastric cancer is one of the most common cancers leading to tumor-related deaths worldwide. Chicoric acid (CA) exhibits a variety of protective effects in different diseases. However, its role in regulating tumor progression has not been reported. Autophagy, as a conserved catabolic process, sustains cellular homoeostasis responding to stress to modulate cell fate. In the study, the effects of CA on gastric cancer were investigated. The results indicated that CA treatment markedly reduced the cell viability and induced apoptosis in gastric cancer cells, and prevented tumor growth in an established xenograft gastric cancer model. Furthermore, CA exposure significantly induced autophagy both in gastric cancer cells and tumor samples, as evidenced by the up-regulated expression of LC3II. Moreover, phosphorylated AMP-activated protein kinase (AMPK) and p70S6 kinase (p70s6k) expression were obviously promoted by CA in vitro and in vivo. Importantly, blocking AMPK activation abrogated CA-induced expression of LC3II in gastric cancer cells. In addition, endoplasmic reticulum (ER) stress in tumor samples or cells was markedly induced by CA treatment through promoting the expression of associated signals such as Parkin, protein kinase RNA-like ER kinase (PERK), activating transcription factors 4 (ATF4) and ATF6. Importantly, these effects were abolished by the inhibition of AMPK signaling. Collectively, our findings indicated that CA prevents human gastric cancer progression by inducing autophagy partly through the activation of AMPK, and represents an effective therapeutic strategy against gastric cancer development.

Quinalizarin induces cycle arrest and apoptosis via reactive oxygen species-mediated signaling pathways in human melanoma A375 cells

Quinalizarin, a bioactive and highly selective compound, is known to promote apoptosis in colon and lung cancer cells. However, studies evaluating quinalizarin-induced apoptosis in melanoma cells have not been conducted. In the present study, we investigated the underlying mechanisms of antimelanoma activity of quinalizarin in human melanoma A375 cells. The MTT assay and Trypan blue staining were used to evaluate the cell viability. The flow cytometry was used to detect cell cycle, apoptosis and reactive oxygen species (ROS). Western blot was used to detect the expression of cell cycle and apoptosis-related proteins, MAPK, and STAT3. The results revealed a significant dose and time dependent effect of quinalizarin on inhibiting proliferation in three kinds of human melanoma cells, and had no significant toxic effects on normal cells. Moreover, quinalizarin triggered G2/M phase cell arrest by modulating the protein expression levels of CDK 1/2, cyclin A, cyclin B, p21 and p27, and induced apoptosis by down-regulating the antiapoptotic protein Bcl-2 and upregulating the proapoptotic protein BAD, leading to the activation of caspase-3 and PARP in the caspase cascade in A375 cells. Quinalizarin treatment led to apoptosis of A375 cells via activation of MAPK and inhibition of STAT3 signaling pathways. In addition, quinalizarin increased the level of ROS, but ROS scavenger NAC inhibited quinalizarin-induced apoptosis by regulating MAPK and STAT3 signaling pathways. In summary, quinalizarin induces cell cycle arrest and apoptosis via ROS-mediated MAPK and STAT3 signaling pathways in human melanoma A375 cells, and quinalizarin may be used as a novel and effective antimelanoma therapeutic.

Carpesium divaricatum Sieb. & Zucc. Revisited: Newly Identified Constituents from Aerial Parts of the Plant and Their Possible Contribution to the Biological Activity of the Plant

Carpesium divaricatum Sieb. & Zucc. has a long history of use as both a medicinal and a food plant. However, except for terpenoids, its chemical constituents have remained poorly investigated. The composition of hydroalcoholic extract from aerial parts of C. divaricatum was analyzed by HPLC-DAD-MSⁿ, revealing the presence of numerous caffeic acid derivatives that were formerly unknown constituents of the plant. In all, 17 compounds, including commonly found chlorogenic acids and rarely occurring butyryl and methylbutyryl tricaffeoylhexaric acids, were tentatively identified. Fractionation of lipophilic extract from cultivated shoots led to the isolation of 12-oxo-phytodienoic acid (12-OPDA), which is a newly identified constituent of the plant. The compound, at concentrations of 0.5, 1.0, and 2.5 μM, significantly reduced IL-8, IL-1β, TNFα, and CCL2 excretion by lipopolysaccharide (LPS)-stimulated human neutrophils. Reactive oxygen species (ROS) production induced by f-MLP was also significantly diminished in the neutrophils pretreated by 12-OPDA. The newly identified constituents of the plant seem to be partly responsible for its pharmacological activity and elevate the value of C. divaricatum as a potential functional food.

Vitexin ameliorates high fat diet-induced obesity in male C57BL/6J mice via the AMPKα-mediated pathway

Vitexin, a bioactive compound isolated from hawthorn leaf extracts, can prevent HFD-induced obesity/adipogenesis via the AMPKα mediated pathway.

Red pepper seed water extract inhibits preadipocyte differentiation and induces mature adipocyte apoptosis in 3T3-L1 cells

BACKGROUND/OBJECTIVES

Reducing the number of adipocytes by inducing apoptosis of mature adipocytes as well as suppressing differentiation of preadipocytes plays an important role in preventing obesity. This study examines the anti-adipogenic and pro-apoptotic effect of red pepper seed water extract (RPS) prepared at 4℃ (RPS4) in 3T3-L1 cells.

MATERIALS/METHODS

Effect of RPS4 or its fractions on lipid accumulation was determined in 3T3-L1 cells using oil red O (ORO) staining. The expressions of AMP-activated protein kinase (AMPK) and adipogenic associated proteins [peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding proteins α (C/EBP α), sterol regulatory element binding protein-1c (SREBP-1c), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC)] were measured in 3T3-L1 cells treated with RPS4. Apoptosis and the expression of Akt and Bcl-2 family proteins [B-cell lymphoma 2 (Bcl-2), Bcl-2-associated death promoter (Bad), Bcl-2 like protein 4 (Bax), Bal-2 homologous antagonist/killer (Bak)] were measured in mature 3T3-L1 cells treated with RPS4.

RESULTS

Treatment of RPS4 (0-75 µg/mL) or its fractions (0-50 µg/mL) for 24 h did not have an apparent cytotoxicity on pre and mature 3T3-L1 cells. RPS4 significantly suppressed differentiation and cellular lipid accumulation by increasing the phosphorylation of AMPK and reducing the expression of PPAR-γ, C/EBP α, SREBP-1c, FAS, and ACC. In addition, all fractions except ethyl acetate fraction significantly suppressed cellular lipid accumulation. RPS4 induced the apoptosis of mature adipocytes by hypophosphorylating Akt, increasing the expression of the pro-apoptotic proteins, Bak, Bax, and Bad, and reducing the expression of the anti-apoptotic proteins, Bcl-2 and p-Bad.

CONCLUSIONS

These finding suggest that RPS4 can reduce the numbers as well as the size of adipocytes and might useful for preventing and treating obesity.

Harvest Strategies for Optimization of the Content of Bioactive Alkamides and Caffeic Acid Derivatives in Aerial Parts and in Roots of Echinacea purpurea

Aerial parts and roots of Echinacea purpurea were harvested consecutively in order to find the best strategy for harvest of both types of plant material for an optimal content of bioactive alkamides and caffeic acid derivatives. Four caffeic acid derivatives and 15 alkamides were identified and quantified. The aerial parts were harvested in bud, bloom, and wilting stage and the roots were harvested 1 week, 1 month, and 3 months after each harvest of aerial parts. The highest yield per area of both alkamides and caffeic acid derivatives is achieved when the aerial parts are harvested late (wilting stage). To obtain an optimal content of alkamides and caffeic acid derivatives it is not recommendable to harvest the aerial parts and the roots in the same year. If the aerial parts must be harvested, the roots should be harvested 1 week after because this will result in the most optimal concentration of bioactive compounds in both products.

Evaluation of the potential of chicoric acid as a natural food antioxidant

Dietary fat is important for human health, while its excessive consumption or the oxidation of lipids may cause various diseases. In the present study, the potential of chicoric acid (CA) as a natural food antioxidant was evaluated. To evaluate this, spectrophotometry analysis measured CA antioxidant activity, the analytical method of the sanitary standard of edible lard and rapeseed oil measured CA anti-oil oxidation, the Oxford cup method measured CA anti-microbial activity, Oil red O staining assessed intracellular triglycerides following CA administration, and RT-qPCR analysis and ELISA assessed CA anti-inflammatory activity. The results indicated that CA had a marked scavenging capacity for the 2,2-diphenyl-1-picrylhydrazyl radical, as well as a reductive action, and after incubation for 5 days, 0.05% CA achieved a significantly higher peroxide value than 0.02% tert-butylhydroquinone used as a reference (P<0.05). In addition, 160 nM CA inhibited the growth of a variety of common pathogenic microbes in humans, significantly inhibited fat droplet formation (P<0.05) and reduced the production of interleukin-1β and tumor necrosis factor-α in a dose-dependent manner (P<0.05). Therefore, functional foods containing CA may be used as natural antioxidant supplements to prevent the oxidation of oil and protect human health.

Cichoric Acid Prevents Free-Fatty-Acid-Induced Lipid Metabolism Disorders via Regulating Bmal1 in HepG2 Cells

Cichoric acid (CA), a polyphenol component from Echinacea purpurea, exhibits preventive effects on liver lipid-metabolism disorders in obesity. This research aimed to determine the role of circadian rhythm signaling during the process of CA-attenuated lipid accumulation in hepatocytes. In the current study, CA treatments improved cell morphology changes and hepatic lipid levels, which were triggered by free fatty acids (2:1, oleate: palmitate) in a dose-dependent way. Besides, CA (200 μM) regulated the circadian rhythm expressions of clock genes and the relatively shallow daily oscillations. Moreover, silencing Bmal1 significantly blocked the p-Akt/Akt pathway to 80.1% ± 1.5% and the p-GSK3β/GSK3β pathway to 64.7% ± 2.8% ( p < 0.05). Furthermore, silencing Bmal1 elevated the expressions of FAS and ACC to 122.4% ± 5.6% and 114.9% ± 1.7% in protein levels ( p < 0.05) and to 166.5% ± 18.5% and 131.4% ± 5.5% in mRNA levels ( p < 0.05). Therefore, our results demonstrated that CA has a Bmal1 resistance to lipid accumulation by enhancing the Akt/GSK3β signaling pathways and modulating the downstream expressions related to lipid metabolism, which indicated that CA might be useful as a natural and promising nonalcoholic fatty liver diseases (NAFLD) modulator.

Chicoric acid is a potent anti-atherosclerotic ingredient by anti-oxidant action and anti-inflammation capacity

Atherosclerotic cardiovascular disease is linked to both oxidative stress and endothelial cell dysfunction. Chicoric acid has antioxidant and anti-inflammatory properties. In the present investigation, we demonstrated that chicoric acid inhibits oxidized low-density lipoprotein (oxLDL)-facilitated dysfunction in human umbilical vein endothelial cells (HUVECs). Oxidative injuries were tested by investigating the formation of intracellular reactive oxygen species (ROS) and by examining the activity of antioxidant enzymes and the function of endothelial nitric oxide synthase (eNOS). We also confirmed that chicoric acid mitigates apoptotic features caused by oxLDL, such as the subsequent break down of mitochondrial transmembrane potential and the activation of Bax, which promote DNA strand breaks and activate caspase-3. Moreover, our data revealed that chicoric acid attenuated the oxLDL activation of NF-κB, the attachment of THP-1 cells and the overexpression of adhesion molecules in human endothelial cells. The results of this study suggest a potential molecular mechanism through which chicoric acid inhibits oxLDL-induced human endothelial dysfunction.

Chicoric Acid Improves Heart and Blood Responses to Hypobaric Hypoxia in Tibetan Yaks

Yak is a wild bovine species living on the Qinghai Tibet Plateau that demonstrates good adaptability to the hypoxic environment. Chicoric acid, a natural phenolic compound, is known as having anti-oxidant, antiviral, anti-inflammatory and analgesic properties. However, its effect on hypoxia adaptability of yak is still unclear. In this study 40 yaks were selected that were of similar age, parity and weight, and divided into the control group and experimental groups 1, 2, 3, randomly. Results showed that chicoric acid significantly improved RBC, HGB, and WBC. There are significantly beneficial effects to increasing total protein contents ([Formula: see text]): all treatments increased HDL-C contents, and supplementations 100[Formula: see text]mg/h significantly decreased the content of TG on the 60th day ([Formula: see text]). Contents of the serum related enzymes like ALP, GOP and GPT showed varying degrees of change, but no significant differences and the indexes of anti-oxidant capacity (T-AOC and GSH-Px) were significantly improved ([Formula: see text]), but MDA was decreased ([Formula: see text]) under the action of the chicoric acid. Hypoxia-inducible factor in serum such as HIF-2[Formula: see text], EPO, ROS, Fe[Formula: see text] and Tf are all significantly decreased ([Formula: see text]). The myocardial mitochondrial parameters mtDNA, UCP2, PGC1-[Formula: see text], NRF1 and mitochondrial complexes were altered remarkably. Some indicators of glucose metabolism presented variation trends. Taken together, chicoric acid has shown a positive effect on the adaptive ability of yak in high altitude, hypoxic environment in plateau areas. Our findings reported a new potential means to enhance immunity and inflammatory response and improve the anti-oxidant capacity.

MAPK pathway mediates the anti-oxidative effect of chicoric acid against cerebral ischemia-reperfusion injury in vivo

The aim of the present study was to investigate the protective effect of chicoric acid on oxidative stress and inflammation in rats with cerebral ischemia-reperfusion injury. A cerebral ischemia-reperfusion injury rat model was created via transient middle cerebral artery occlusion (MCAO) and rats were treated with various doses of chicoric acid (0, 1, 10 and 100 mg/kg). Neurological deficits and infarct volume were used to estimate the protective effects of chicoric acid treatment. Levels of reactive oxygen species (ROS), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, nitric oxide (NO) and prostaglandin E2 (PGE2) were assessed. Western blot analysis was also used to measure the expression of cyclooxygenase (COX)-2, p38-mitogen activated protein kinase (MAPK), c-Jun, phosphorylated protein kinase B (p-AKT) and AKT. Chicoric acid exposure was observed to reduce neurological deficits and infarct volume in rats with cerebral ischemia-reperfusion injury. In addition, ROS production and inflammation were significantly suppressed following treatment with chicoric acid. Chicoric acid was demonstrated to significantly inhibit the upregulation of NO and PGE2 levels in rats following MCAO. Furthermore, chicoric acid significantly suppressed the MCAO-induced promotion of COX-2, p38-MAPK and c-Jun protein expression and enhanced the inhibition of p-AKT/AKT. These results suggest that chicoric acid has a protective effect, preventing oxidative stress and inflammation in rats with cerebral ischemia-reperfusion injury via the p38-MAPK, c-Jun and AKT signaling pathways.

Inhibition of cell proliferation and triggering of apoptosis by agrimonolide through MAP kinase (ERK and p38) pathways in human gastric cancer AGS cells

Data from the present study showed that agrimonolide exhibited a high anti-proliferation effect against human gastric cancer AGS cells. Flow cytometric analysis revealed that the number of total apoptotic cells increased after the treatment with the agrimonolide in a dose-dependent manner. In addition, it was found that agrimonolide-induced cell apoptosis was associated with the increase in the (Bcl-2 Associated X Protein, BAX)/(B-cell lymphoma-2, Bcl-2) ratio and the activation of cleaved caspase-3. MAPK (p38, c-Jun N-terminal kinase, and ERK1/2) signaling pathways were involved in agrimonolide-induced apoptosis. Cells were exposed to 40 μM of agrimonolide and the level of phospho-ERK/ERK protein was increased to 7.0-fold as compared to the control, and the expression of phospho-p38 protein showed a significant 6.2-fold increase after 24 h incubation, as compared to the control. The employment of protein kinase inhibitors of PD98059 and SB203580, showed the block effects of agrimonolide on the activation of caspase-3 and apoptosis.

Possible Mechanisms of the Prevention of Doxorubicin Toxicity by Cichoric Acid-Antioxidant Nutrient

Skin is the largest organ in the human body, and which protects organism against unfavorable external factors e.g., chemicals, environment pollutants, allergens, microorganisms, and it plays a crucial role in maintaining general homeostasis. It is also an important target of oxidative stress due to the activity of oxygen reactive species (ROS), which are constantly generated in the fibroblasts in response to exogenous or endogenous prooxidant agents. An example of such compound with proved prooxidant activity is Doxorubicin (DOX), which is an effective anticancer agent belongs in anthracycline antibiotic group. Increasingly frequent implementation of various strategies to reduce undesirable DOX side effects was observed. Very promising results come from the combination of DOX with dietary antioxidants from the polyphenol group of compounds, such as cichoric acid (CA) in order to lower oxidative stress level. The aim of this work was to evaluate the influence of CA combined with DOX on the oxidative stress parameters in fibroblasts, which constitute the main cells in human skin. We also wanted to examine anti-apoptotic activity of CA in fibroblasts treated with selected concentrations of DOX. Results obtained from the combination of DOX with CA revealed that CA exhibits cytoprotective activity against DOX-induced damage by lowering oxidative stress level and by inhibiting apoptosis. The present finding may indicate that CA may serve as antioxidative and anti-apoptotic agent, active against DOX-induced damage.

Chicoric acid prevents PDGF-BB-induced VSMC dedifferentiation, proliferation and migration by suppressing ROS/NFκB/mTOR/P70S6K signaling cascade

Phenotypic switch of vascular smooth muscle cells (VSMCs) is characterized by increased expressions of VSMC synthetic markers and decreased levels of VSMC contractile markers, which is an important step for VSMC proliferation and migration during the development and progression of cardiovascular diseases including atherosclerosis. Chicoric acid (CA) is identified to exert powerful cardiovascular protective effects. However, little is known about the effects of CA on VSMC biology. Herein, in cultured VSMCs, we showed that pretreatment with CA dose-dependently suppressed platelet-derived growth factor type BB (PDGF-BB)-induced VSMC phenotypic alteration, proliferation and migration. Mechanistically, PDGF-BB-treated VSMCs exhibited higher mammalian target of rapamycin (mTOR) and P70S6K phosphorylation, which was attenuated by CA pretreatment, diphenyleneiodonium chloride (DPI), reactive oxygen species (ROS) scavenger N-acetyl-l-cysteine (NAC) and nuclear factor-κB (NFκB) inhibitor Bay117082. PDGF-BB-triggered ROS production and p65-NFκB activation were inhibited by CA. In addition, both NAC and DPI abolished PDGF-BB-evoked p65-NFκB nuclear translocation, phosphorylation and degradation of Inhibitor κBα (IκBα). Of note, blockade of ROS/NFκB/mTOR/P70S6K signaling cascade prevented PDGF-BB-evoked VSMC phenotypic transformation, proliferation and migration. CA treatment prevented intimal hyperplasia and vascular remodeling in rat models of carotid artery ligation in vivo. These results suggest that CA impedes PDGF-BB-induced VSMC phenotypic switching, proliferation, migration and neointima formation via inhibition of ROS/NFκB/mTOR/P70S6K signaling cascade.

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Chicoric acid attenuated PDGF-BB-evoked VSMC phenotypic transformation, proliferation and migration.

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Chicoric acid antagonized the activated ROS/NFκB/mTOR/P70S6K signaling pathway in VSMCs.

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Chicoric acid treatment prevented intimal hyperplasia in rat models of carotid artery ligation.

Chicoric Acid Ameliorates Lipopolysaccharide-Induced Oxidative Stress via Promoting the Keap1/Nrf2 Transcriptional Signaling Pathway in BV-2 Microglial Cells and Mouse Brain

As a major nutraceutical component of a typical Mediterranean vegetable chicory, chicoric acid (CA) has been well-documented due to its excellent antioxidant and antiobesity bioactivities. In the current study, the effects of CA on lipopolysaccharide (LPS)-stimulated oxidative stress in BV-2 microglia and C57BL/6J mice and the underlying molecular mechanisms were investigated. Results demonstrated that CA significantly reversed LPS-elicited cell viability decrease, mitochondrial dysfunction, activation of NFκB and MAPK stress pathways, and inflammation responses via balancing cellular redox status. Furthermore, molecular modeling study demonstrated that CA could insert into the pocket of Keap1 and up-regulated Nrf2 signaling and, thus, transcriptionally regulate downstream expressions of antioxidant enzymes including HO-1 and NQO-1 in both microglial cells and ip injection of LPS-treated mouse brain. These results suggested that CA attenuated LPS-induced oxidative stress via mediating Keap1/Nrf2 transcriptional pathways and downstream enzyme expressions, which indicated that CA has great potential as a nutritional preventive strategy in oxidative stress-related neuroinflammation.

Chicoric acid supplementation ameliorates cognitive impairment induced by oxidative stress via promotion of antioxidant defense system

Illustration of effects of chicoric acid on neuroprotection againstd-gal-induced memory impairmentviainflammation and oxidative stress.