ABSTRACT
[This corrects the article DOI: 10.3389/fphar.2020.00695.].
ABSTRACT
Sweet potato pulp water (SPPW) is a kind of sweet potato starch processing by-product with rich nutrition but low utilization. The impacts of different proportions of Coriolus versicolor (C. versicolor, CV) fermented sweet potato pulp water (CV-SPPW) on the physicochemical, structural and metabolic properties of yogurt were investigated. Compared with 0% group, the hardness index, elasticity index and cohesion of the 10% sample group increased by 1.9-fold, 55.7% and 1.39-fold, respectively. When CV-SPPW was added at an amount of 10%, the microstructure and sensory scores of yogurts were considered as the optimal. Metabolic pathway analysis indicated that the changes of yogurts were mainly involved in sugar metabolism and amino acid metabolism, and that the carbohydrate metabolites produced mainly included cellobiose, maltitol, d-trehalose and d-maltose. The CV-SPPW improved the structural characteristics of yogurts to varying degrees and the fermented yogurts exhibited better viscosity properties.
ABSTRACT
Mammalian cytochrome P450 1A (CYP1A) are key phase I xenobiotic-metabolizing enzymes that play a distinctive role in metabolic activation or metabolic clearance of a variety of procarcinogens, drugs, and endogenous substances. Human CYP1A subfamily contains two members (hCYP1A1 and hCYP1A2), which are known to catalyze the oxidative activation of some environmental procarcinogens into carcinogenic species. Increasing evidence has demonstrated that CYP1A inhibitor therapies are promising strategies for cancer chemoprevention or overcoming CYP1A-associated drug toxicity and resistance. Herein, we reviewed recent advances in the discovery and characterization of hCYP1A inhibitors, from the discovery approaches to structural features and biomedical applications of hCYP1A inhibitors. The inhibition potentials, inhibition modes, and inhibition constants of all reported hCYP1A inhibitors are comprehensively summarized. Meanwhile, the structural features and structure-activity relationships of different classes of hCYP1A1 and hCYP1A2 inhibitors are analyzed and discussed in depth. Furthermore, the major challenges and future directions for this field are presented and highlighted. Collectively, the information and knowledge presented here will strongly facilitate the researchers to discover and develop more efficacious CYP1A inhibitors for specific purposes, such as chemo-preventive agents or as tool molecules in hCYP1A-related fundamental studies.
Subject(s)
Cytochrome P-450 CYP1A1 , Cytochrome P-450 CYP1A2 , Animals , Humans , Cytochrome P-450 CYP1A1/metabolism , Cytochrome P-450 CYP1A2/metabolism , Cytochrome P-450 Enzyme System/metabolism , Mammals/metabolismABSTRACT
Monoamine oxidase-B (MAO-B), as a principal metabolizing enzyme, plays important roles in the metabolism of catecholamines and xenobiotics in the central nervous system and peripheral tissues. Safinamide, the third-generation reversible MAO-B inhibitor, has potential to alleviate many neurological diseases such as Parkinson's disease (PD) and depression. Exposure to clinical psychotropic drugs often has adverse effects on fetuses. Currently, a variety of studies of safinamide focus on its curative effect and pharmacological effect, while its side effect of embryonic development is barely studied. In this study, we used zebrafish as a model to evaluate the embryonic developmental toxicity of safinamide. Our results revealed that higher concentrations (30 µM) of safinamide treatment caused a decrease in hatching rate and an increase in malformation and mortality in zebrafish larvae. Meanwhile, we observed that lower safinamide exposure (10 µM) increased the body length of zebrafish larvae and resulted in hyperactivity-like behaviors. In addition, an increased trend in dopamine (DA) level was found in 3.3 µM and 10 µM safinamide-exposed groups. Transcriptome analysis identified that safinamide exposure may disturb a variety of physiological processes such as neuroactive ligand-receptor interaction signaling pathway. In summary, our study reveals that safinamide may cause developmental defects in zebrafish larvae and provides insights into its toxic reactions in early develoment.
ABSTRACT
Vesicular monoamine transporter 2 (VMAT-2) functions by uptake of cytoplasmic monoamines into vesicles for storage. Valbenazine (VBZ) is a newly FDA-approved oral VMAT-2 inhibitor used for the treatment of movement disorders such as tardive dyskinesia (TD), and Tourette syndrome (TS). Clinical data shows that VBZ is a relatively safe drug with no cardiotoxicity or hepatotoxicity. However, the effect of VBZ on embryonic development remains unknown. Here, we use zebrafish larvae as an animal model to demonstrate that VBZ exposure causes premature hatching and increased body size and hyperactivity-like behaviors in zebrafish larvae. In addition, VBZ exposure leads to increased dopamine (DA) and Glutamate (Glu) levels. Moreover, an increase of growth hormone (gh) and enriched PI3K/AKT signaling were found in VBZ-exposed zebrafish larvae, which may explain their accelerated development. In summary, VBZ exposure may be developmentally toxic in zebrafish larvae.
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The cytochrome P450 enzymes (CYPs), a group of heme-containing enzymes, catalyze oxidative metabolism of a wide range of drugs and xenobiotics, as well as different endogenous molecules. Strong inhibition of human CYPs is the most common cause of clinically associated pharmacokinetic drug-drug/herb-drug interactions (DDIs/HDIs), which may result in serious adverse drug reactions, even toxicity. Accurate and rapid assessing of the inhibition potentials on CYP activities for therapeutic agents is crucial for the prediction of clinically relevant DDIs/HDIs. Over the past few decades, significant efforts have been invested into developing optical substrates for the human CYPs, generating a variety of powerful tools for high-throughput assays to detect CYP activities in biologic specimens and for screening of CYP inhibitors. This minireview focuses on recent advances in optical substrates developments for human CYPs, as well as their applications in screening CYP inhibitors and DDIs/HDIs studies. The examples for rational design and optimization of highly specific optical substrates for the target CYP enzyme, as well as applications in investigating CYP-mediated DDIs, are illustrated. Finally, the challenges and future perspectives in this field are proposed. Collectively, this review summarizes the reported optical-based biochemical assays for highly efficient CYP activities detection, which strongly facilitated the discovery of CYP inhibitors and the investigations on CYP-mediated DDIs. SIGNIFICANCE STATEMENT: Optical substrates for cytochrome P450 enzymes (CYPs) have emerged as powerful tools for the construction of high-throughput assays for screening of CYP inhibitors. This mini-review covers the advances and challenges in the development of highly specific optical substrates for sensing human CYP isoenzymes, as well as their applications in constructing fluorescence-based high-throughput assays for investigating CYP-mediated drug-drug interactions.
Subject(s)
Cytochrome P-450 Enzyme System , High-Throughput Screening Assays , Humans , Cytochrome P-450 Enzyme System/metabolism , Drug Interactions , Herb-Drug InteractionsABSTRACT
Human cytochrome P450 1B1 (hCYP1B1), an extrahepatic cytochrome P450 enzyme over-expressed in various tumors, has been validated as a promising target for preventing and treating cancers. Herein, two series of chalcone derivatives were synthesized to discover potent hCYP1B1 inhibitors without AhR agonist effect. Structure-activity relationship (SAR) studies demonstrated that 4'-trifluoromethyl on the B-ring strongly enhanced the anti-hCYP1B1 effects, identifying A9 as a promising lead compound. Further SAR analysis on A9 derivatives (modified A-ring of 4'-trifluoromethylchalcone) showed that introducing 2-methoxyl improved the anti-hCYP1B1 effect and selectivity, while introducing a methoxyl at the C-4 site was beneficial for avoiding AhR activation. Ultimately, five 4'-trifluoromethyl chalcones were identified as potent hCYP1B1 inhibitors (IC50 < 10 nM), while B18 exhibits the most potent anti-hCYP1B1 effect (IC50 = 3.6 nM), suitable metabolic stability and good cell-permeability. B18 also acted as an AhR antagonist and could down-regulate hCYP1B1 in living systems. Mechanistic studies showed that B18 potently inhibited hCYP1B1 in a competitive inhibition manner (Ki = 3.92 nM), while docking simulations revealed that B18 could tightly bind to the catalytic cavity of hCYP1B1 mainly via hydrophobic and hydrogen-bonding interactions. Furthermore, B18 could potently inhibit hCYP1B1 in living cells and showed remarkable anti-migration ability on MFC-7 cells. Taken together, this study deciphered the SARs of chalcones as hCYP1B1 inhibitors and provided several potent hCYP1B1 inhibitors as promising candidates for the development of more efficacious anti-migration agents.
Subject(s)
Chalcones , Humans , Chalcones/pharmacology , Chalcones/chemistry , Cytochrome P-450 Enzyme System/metabolism , Structure-Activity Relationship , Molecular Docking SimulationABSTRACT
Hyperlipidemia an immense group of acquired or genetic metabolic disorders that is characterized by an excess of lipids in the bloodstream. Altogether, they have a high prevalence worldwide and constitute a major threat to human health. Glycosaminoglycans (GAG) are natural biomolecules that have hypolipidemic activity. The purpose of this study was to investigate the potential hypolipidemic effect of glycosaminoglycans extracted from Ostrea rivularis (OGAG) on hyperlipidemic zebrafish, as well as the possible underlying mechanism of such effect. Dietary supplementation with OGAG during 4 weeks significantly reduced the serum and hepatic lipid levels and the hepatosomatic index in hyperlipidemic zebrafish. In addition, histopathological showed that OGAG supplementation decreases the volume and number of lipid droplets in hepatocytes. Transcriptome and real-time quantitative polymerase chain reaction analysis revealed that the gene expression levels of PPARγ, SCD, HMGRA, ACAT2, HMGCS, and HMGCR were significantly downregulated by OGAG treatment in hepatocytes, whereas those of CD36, FABP2, FABP6, ABCG5, and CYP7A1 were significantly upregulated. This suggests that the hypolipidemic effect of OGAG relies on increasing the ketogenic metabolism of fatty acids, inhibiting cholesterol synthesis, and enhancing the transformation of cholesterol to bile acid. Furthermore, OGAG treatment improved gut microbiota imbalance by reducing the Firmicutes-to-Bacteroidetes ratio, increasing the relative abundance of beneficial bacteria (Bacteroidetes, Verrucomicrobia, Acidobacteria, and Sphingomonas), and reducing the relative abundance of harmful bacteria (Proteobacteria, Cohaesibacter, Vibrio, and Terrisporobacter). These findings highlight the potential benefit of implementing OGAG as a dietary supplement to prevent and treat hyperlipidemia.
ABSTRACT
Introduction: Intracellular calcium overload is an important contributor to myocardial ischemia/reperfusion (MI/R) injury. Total saponins of the traditional Chinese medicinal plant Aralia elata (Miq.) Seem. (AS) are beneficial for treating MI/R injury, and Calenduloside E (CE) is the main active ingredient of AS. Objectives: This study aimed to investigate the effects of CE on MI/R injury and determine its specific regulatory mechanisms. Methods: To verify whether CE mediated cardiac protection in vivo and in vitro, we performed MI/R surgery in SD rats and subjected neonatal rat ventricular myocytes (NRVMs) to hypoxia-reoxygenation (HR). CE's cardioprotective against MI/R injury was detected by Evans blue/TTC staining, echocardiography, HE staining, myocardial enzyme levels. Impedance and field potential recording, and patch-clamp techniques of human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were used to detect the function of L-type calcium channels (LTCC). The mechanisms underlying between CE and LTCC was studied through western blot, immunofluorescence, and immunohistochemistry. Drug affinity responsive target stability (DARTS) and co-immunoprecipitation (co-IP) used to further clarify the effect of CE on LTCC and BAG3. Results: We found that CE protected against MI/R injury by inhibiting calcium overload. Furthermore, CE improved contraction and field potential signals of hiPSC-CMs and restored sarcomere contraction and calcium transient of adult rat ventricular myocytes (ARVMs). Moreover, patch-clamp data showed that CE suppressed increased L-type calcium current (ICa,L) caused by LTCC agonist, proving that CE could regulate calcium homeostasis through LTCC. Importantly, we found that CE promoted the interaction between LTCC and Bcl2-associated athanogene 3 (BAG3) by co-IP and DARTS. Conclusion: Our results demonstrate that CE enhanced LTCC-BAG3 interaction to reduce MI/R induced-calcium overload, exerting a cardioprotective effect.
Subject(s)
Myocardial Reperfusion Injury , Saponins , Adaptor Proteins, Signal Transducing , Animals , Apoptosis , Apoptosis Regulatory Proteins , Calcium/metabolism , Calcium Channels, L-Type/genetics , Myocardial Reperfusion Injury/drug therapy , Oleanolic Acid/analogs & derivatives , Rats , Rats, Sprague-Dawley , Saponins/pharmacologyABSTRACT
[This corrects the article DOI: 10.3389/fphar.2020.00695.].
ABSTRACT
Until now, there has been little research on the intestinal microbial community of horseshoe crabs. To fill this gap, we investigated the microbiome composition of the Chinese horseshoe crab, Tachypleus tridentatus, and the mangrove horseshoe crab, Carcinoscorpius rotundicauda. We sequenced the 16S rRNA gene of intestinal bacterial species and compared the microbial community structure and diversity. Next, we show that the total effective bacterial sequence was 36,865 reads, and the average annotated operational taxonomic unit (OTU) number was 240. Through hierarchical clustering analysis and principal coordinate analysis samples from two horseshoe crab species, we found that the intestinal flora of the same horseshoe crab species was relatively concentrated, while the microbiome of a different horseshoe crab species were significantly separated. Cluster analysis showed that two samples, one from Chinese horseshoe crabs and one from mangrove horseshoe crabs, had similar microbial community structure, while other samples were relatively discrete. The gut microbiota of the mangrove horseshoe crab were dominated by the phyla Tenericutes (42.71%), Firmicutes (24.27%), and Proteobacteria (20.39%), while the top three phyla in the Chinese horseshoe crab intestinal tract were Tenericutes (57.19%), Proteobacteria (22.14%), and Bacteroidetes (7.38%). To intuitively understand the similarity and overlap of the OTU composition of each group, we performed Venn diagram analysis. The two species shared 284 OTUs, accounting for 81.8% of the total. This indicates that although there is high similarity between mangrove and Chinese horseshoe crab in gastrointestinal microbial community structure, there are also some differences, which deserve further discussion.
Subject(s)
Horseshoe Crabs , Microbiota , Animals , China , Horseshoe Crabs/genetics , Intestines , RNA, Ribosomal, 16S/geneticsABSTRACT
Hyperglycaemia-induced retinal microvascular endothelial cell apoptosis is a critical and principle event in diabetic retinopathy (DR), which involves a series of complex processes such as mitochondrial dysfunction and oxidative stress. Ginsenoside Re (Re), a key ingredients of ginseng, is considered to have various pharmacologic functions, such as antioxidative, inhibition of inflammation and anti-apoptotic properties. However, the effects of Re in DR and the related mechanisms of endothelial cell injury induced by high glucose (HG) exposure remain unclear. The present study was designed to investigate and evaluate the ability of Re to ameliorate HG-induced retinal endothelial RF/6A cell injury and the potential mechanisms involved in the hypoxia-inducible factor-1-alpha (HIF-1α)/vascular endothelial growth factor (VEGF) signaling regulated by phosphoinositide 3-kinase (PI3K)/AKT pathway. Our results showed that preincubation with Re exerted cytoprotective effects by reversing the HG-induced decrease in RF/6A cell viability, downregulation of apoptosis rate and inhibition of oxidative-related enzymes, thereby reducing the excess intracellular reactive oxygen species (ROS) and HG-triggered RF/6A cell injury. In addition, Western blot analysis results showed ginsenoside Re significantly increased HIF-1α expression in the cytoplasm but decreased its expression in the nucleus, suggesting that it reduced the translocation of HIF-1α from the cytoplasm to the nucleus, and downregulated VEGF level. Moreover, this effect is involved in the activation of the PI3K/Akt pathway. LY294002, a PI3K inhibitor, was used to block the Akt pathway. Afterwards, the effects of Re on the regulation of apoptotic related proteins, VEGF and HIF-1α nuclear transcription was partially reversed. These findings suggested the exerting protective effects of ginsenoside Re were associated with regulating of PI3K/AKT and HIF-1α/VEGF signaling pathway, which indicates that ginsenoside Re may ameliorates HG-induced retinal angiogenesis and suggests the potential for the development of Re as a therapeutic for DR.
ABSTRACT
NCMN (N-(3-carboxy propyl)-4-methoxy-1,8-naphthalimide), a newly developed ratiometric two-photon fluorescent probe for human Cytochrome P450 1A (CYP1A), shows the best combination of specificity and reactivity for real-time detection of the enzymatic activities of CYP1A in complex biological systems. This study aimed to investigate the interspecies variation in NCMN-O-demethylation in commercially available liver microsomes from human, mouse, rat, beagle dog, minipig and cynomolgus monkey. Metabolite profiling demonstrated that NCMN could be O-demethylated in liver microsomes from all species but the reaction rate varied considerably. CYP1A was the major isoform involved in NCMN-O-demethylation in all examined liver microsomes based on the chemical inhibition assays. Furafylline, a specific inhibitor of mammalian CYP1A, displayed differential inhibitory effects on NCMN-O-demethylation in all tested species. Kinetic analyses demonstrated that NCMN-O-demethylation in liver microsomes form rat, minipig and cynomolgus monkey followed biphasic kinetics, while in liver microsomes form human, mouse and beagle dog obeyed Michaelis-Menten kinetics, the kinetic parameters from various species are much varied, while NCMN-O-demethylation in MLM exhibited the highest similarity of specificity, kinetic behavior and intrinsic clearance as that in HLM. These findings will be very helpful for the rational use of NCMN as a practical tool to decipher the functions of mammalian CYP1A or to study CYP1A associated drug-drug interactions in vivo.
Subject(s)
Cytochrome P-450 CYP1A1/metabolism , Demethylation/drug effects , Fluorescent Dyes/metabolism , Isoquinolines/metabolism , Microsomes, Liver/enzymology , Animals , Biotransformation/drug effects , Cytochrome P-450 CYP1A1/antagonists & inhibitors , Cytochrome P-450 CYP1A1/chemistry , Cytochrome P-450 Enzyme Inhibitors/pharmacology , Dogs , Fluorescent Dyes/chemistry , Humans , Isoquinolines/chemistry , Kinetics , Macaca fascicularis , Mice , Rats , Rats, Sprague-Dawley , Species Specificity , Swine , Swine, Miniature , Theophylline/analogs & derivatives , Theophylline/pharmacologyABSTRACT
[This corrects the article DOI: 10.3389/fendo.2016.00088.].
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Bufotalin (BFT), one of the naturally occurring bufodienolides, has multiple pharmacological and toxicological effects including antitumor activity and cardiotoxicity. This study aimed to character the metabolic pathway(s) of BFT and to identify the key drug metabolizing enzyme(s) responsible for hepatic metabolism of BFT in human, as well as to explore the related molecular mechanism of enzymatic selectivity. The major metabolite of BFT in human liver microsomes (HLMs) was fully identified as 5ß-hydroxylbufotalin by LC-MS/MS and NMR techniques. Reaction phenotyping and chemical inhibition assays showed that CYP3A4 and CYP3A5 were key enzymes responsible for BFT 5ß-hydroxylation. Kinetic analyses demonstrated that BFT 5ß-hydroxylation in both HLMs and human CYP3A4 followed the biphasic kinetics, while BFT 5ß-hydroxylation in CYP3A5 followed substrate inhibition kinetics. Furthermore, molecular docking simulations showed that BFT could bind on two different ligand-binding sites on both CYP3A4 and CYP3A5, which partially explained the different kinetic behaviors of BFT in CYP3A4 and CYP3A5. These findings are very helpful for elucidating the phase I metabolism of BFT in human and for deeper understanding the key interactions between CYP3A enzymes and bufadienolides, as well as for the development of bufadienolide-type drugs with improved pharmacokinetic and safety profiles.
ABSTRACT
Mitochondria play a central role in various critical cellular processes, including energy synthesis, energy supply and apoptosis. Panax notoginseng, a commonly used traditional Chinese medicine, has various pharmacological effects on the human body. Ginsenosides are representative bioactive components of P. notoginseng. Recently, more attention has focused on ginsenoside Rb1 as an antioxidative and anti-inflammatory agent that can protect the nervous system and the cardiovascular system. Numerous studies have shown that Rb1 exerts these effects by regulating mitochondrial energy metabolism, mitochondrial fission and fusion, apoptosis, oxidative stress and reactive oxygen species release, mitophagy and mitochondrial membrane potential. Thus, the mitochondria are pivotal targets of Rb1. This review summarized the available reports of the effects of ginsenoside Rb1 on the regulation of mitochondria and showed that it has a promising role in treating mitochondrial diseases.
Subject(s)
Ginsenosides/pharmacology , Mitochondria/metabolism , Animals , Apoptosis/drug effects , Energy Metabolism/drug effects , Ginsenosides/chemistry , Humans , Oxidative Stress/drug effects , Reactive Oxygen Species/metabolismABSTRACT
Atherosclerosis is an arterial disease associated with inflammation. Hence, the discovery of novel therapeutic agents for suppressing inflammatory responses is urgent and vital for the treatment of atherosclerosis in cardiovascular diseases. The total saponins of Aralia elata (Miq.) Seem. (TAS) are the main components extracted from the Chinese traditional herb Longya Aralia chinensis L., a folk medicine used in Asian countries for treating numerous diseases, enhancing energy and boosting immunity. However, the protective effects of TAS against inflammation-triggered vascular endothelial dysfunction, a critical early event during the course of atherosclerosis, and the potential mechanisms of this protection have been not demonstrated. Accordingly, the aim of this study was to investigate the anti-inflammatory and anti-apoptotic effects and the protective mechanisms of TAS, and show how TAS ameliorates human umbilical vein endothelial cell (HUVEC) damage caused by tumour necrosis factor-α (TNF-α). The results indicated that TAS exerted cytoprotective effects by inhibiting TNF-α-triggered HUVEC apoptosis, mitochondrial membrane potential depolarisation, and the regulation of inflammatory factors (IL-6, MCP-1, and VCAM-1) while suppressing NF-κB transcription. Furthermore, this phenomenon was related to activation of the phosphoinositide 3-kinase (PI3K)/Akt signalling pathway. Blocking the Akt pathway with LY294002, a PI3K inhibitor, reversed the cytoprotective effect of TAS against TNF-α-induced endothelial cell death. Moreover, LY294002 partially abolished the effects of TAS on the upregulation of the Bcl-2 family of proteins and the downregulation of Bax protein expression. In conclusion, the results of our study suggest that TAS suppresses the inflammation and apoptosis of HUVECs induced by TNF-α and that PI3K/Akt signalling plays a key role in promoting cell survival and anti-inflammatory reactions during this process.
Subject(s)
Aralia/chemistry , Endothelial Cells/drug effects , Endothelial Cells/metabolism , NF-kappa B/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Saponins/pharmacology , Signal Transduction/drug effects , Tumor Necrosis Factor-alpha/metabolism , Apoptosis/drug effects , Caspase 3/metabolism , Cell Survival/drug effects , Gene Expression Regulation/drug effects , Human Umbilical Vein Endothelial Cells/drug effects , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Membrane Potential, Mitochondrial/drug effects , Saponins/chemistry , Tumor Necrosis Factor-alpha/pharmacologyABSTRACT
Cerebral ischemia-reperfusion is a complicated pathological process. The injury and cascade reactions caused by cerebral ischemia and reperfusion are characterized by high mortality, high recurrence, and high disability. However, only a limited number of antithrombotic drugs, such as recombinant tissue plasminogen activator (r-TPA), aspirin, and heparin, are currently available for ischemic stroke, and its safety concerns is inevitable which associated with reperfusion injury and hemorrhage. Therefore, it is necessary to further explore and examine some potential neuroprotective agents with treatment for cerebral ischemia and reperfusion injury to reduce safety concerns caused by antithrombotic drugs in ischemic stroke. Ginseng Rg1 (G-Rg1) is a saponin composed of natural active ingredients and derived from the roots or stems of Panax notoginseng and ginseng in traditional Chinese medicine. Its pharmacological effects exert remarkable neurotrophic and neuroprotective effects in the central nervous system. To explore and summarize the protective effects and mechanisms of ginsenoside Rg1 against cerebral ischemia and reperfusion injury, we conducted this review, in which we searched the PubMed database to obtain and organize studies concerning the pharmacological effects and mechanisms of ginsenoside Rg1 against cerebral ischemia and reperfusion injury. This study provides a valuable reference and clues for the development of new agents to combat ischemic stroke. Our summarized review and analysis show that the pharmacological effects of and mechanisms underlying ginsenoside Rg1 activity against cerebral ischemia and reperfusion injury mainly involve 4 sets of mechanisms: anti-oxidant activity and associated apoptosis via the Akt, Nrf2/HO-1, PPARγ/HO-1, extracellular regulated protein kinases (ERK), p38, and c-Jun N-terminal kinase (JNK) pathways (or mitochondrial apoptosis pathway) and the caspase-3/ROCK1/MLC pathway; anti-inflammatory and immune stimulatory-related activities that involve apoptosis or necrosis via MAPK pathways (the JNK1/2 + ERK1/2 and PPARγ/HO-1 pathways), endoplasmic reticulum stress (ERS), high mobility group protein1 (HMGB1)-induced TLR2/4/9 and receptor for advanced glycation end products (RAGE) pathways, and the activation of NF-κB; neurological cell cycle, proliferation, differentiation, and regeneration via the MAPK pathways (JNK1/2 + ERK1/2, PI3K-Akt/mTOR, PKB/Akt and HIF-1α/VEGF pathways); and energy metabolism and the regulation of cellular ATP levels, the blood-brain barrier and other effects via N-methyl-D-aspartic acid (NMDA) receptors, ERS, and AMP/AMPK-GLUT pathways. Collectively, these mechanisms result in significant neuroprotective effects against cerebral ischemic injury. These findings will be valuable in that they should further promote the development of candidate drugs and provide more information to support the application of previous findings in stroke clinical trials.
ABSTRACT
Inflammation is a major contributing factor to the progression of atherosclerosis. Ginsenoside Rb1 (Rb1), an active saponin of Panax notoginseng, has been found to exert beneficial effects on inflammation and oxidative stress. This study investigated the ability of Rb1 to inhibit the formation of atherosclerotic plaques and the potential mechanisms. In this study, the effects of Rb1 on the development of atherosclerosis were investigated in ApoE-/- deficient mice fed with a western diet. Mice were intragastrically administrated with Rb1 (10 mg/kg) for 8 weeks. This study is that ginsenoside Rb1 exerted an inhibitory effect on early atherosclerosis in ApoE-/- mice via decreasing body weight and food intake daily, upregulating the lipid levels of serum plasma, including those of TC, TG and LDL-C and HDL-C and reducing the atherosclerotic plaque area, suppressing inflammatory cytokines (levels of IL-1ß, IL-6 and TNF-α) in the serum of ApoE-/- mice, changing the expression levels of BCL-2, BAX, cleaved caspase-3 and cleaved caspase-9 and weakening apoptosis associated with anti-inflammatory activity. Hence, all these effects against atherosclerosis were tightly associated with regulation of necrosis or apoptosis associated with anti-inflammatory activity. Additionally, the results found that ginsenoside Rb1 increased autophagy flux to inhibit apoptosis via acceleration of autophagy by promoting transformation of LC3 from type I to type II in high-fat diet-induced atherosclerosis in ApoE-/- mice. This finding, along with those of the previous study, provides evidence that Rb1 promotes the process of autophagy to protect against atherosclerosis via regulating BCL-2 family-related apoptosis. These results indicate that Rb1 exhibits therapeutic effects in atherosclerosis by reversing the imbalance between apoptosis and autophagy.