Pinoresinol Diglucoside Alleviates oxLDL-Induced Dysfunction in Human Umbilical Vein Endothelial Cells

Characterization of metabolic features and potential anti-osteoporosis mechanism of pinoresinol diglucoside using metabolite profiling and network pharmacology

RATIONALE

Eucommia cortex is the core herb in traditional Chinese medicine preparations for the treatment of osteoporosis. Pinoresinol diglucoside (PDG), the quality control marker and the key pharmacodynamic component in Eucommia cortex, has attracted global attention because of its definite effects on osteoporosis. However, the in vivo metabolic characteristics of PDG and its anti-osteoporotic mechanism are still unclear, restricting its development and application.

METHODS

Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to analyze the metabolic characteristics of PDG in rats, and its anti-osteoporosis targets and mechanism were predicted using network pharmacology.

RESULTS

A total of 51 metabolites were identified or tentatively characterized in rats after oral administration of PDG (10 mg/kg/day), including 9 in plasma, 28 in urine, 13 in feces, 10 in liver, 4 in heart, 3 in spleen, 11 in kidneys, and 5 in lungs. Furan-ring opening, dimethoxylation, glucuronidation, and sulfation were the main metabolic characteristics of PDG in vivo. The potential mechanism of PDG against osteoporosis was predicted using network pharmacology. PDG and its metabolites could regulate BCL2, MARK3, ALB, and IL6, involving PI3K-Akt signaling pathway, estrogen signaling pathway, and so on.

CONCLUSIONS

This study was the first to demonstrate the metabolic characteristics of PDG in vivo and its potential anti-osteoporosis mechanism, providing the data for further pharmacological validation of PDG in the treatment of osteoporosis.

Identification of a Hydroxygallic Acid Derivative, Zingibroside R1 and a Sterol Lipid as Potential Active Ingredients of Cuscuta chinensis Extract That Has Neuroprotective and Antioxidant Effects in Aged Caenorhabditis elegans

We examined the effects of the extracts from two traditional Chinese medicine plants, Cuscuta chinensis and Eucommia ulmoides, on the healthspan of the model organism Caenorhabditis elegans. C. chinensis increased the short-term memory and the mechanosensory response of aged C. elegans. Furthermore, both extracts improved the resistance towards oxidative stress, and decreased the intracellular level of reactive oxygen species. Chemical analyses of the extracts revealed the presence of several bioactive compounds such as chlorogenic acid, cinnamic acid, and quercetin. A fraction from the C. chinensis extract enriched in zingibroside R1 improved the lifespan, the survival after heat stress, and the locomotion in a manner similar to the full C. chinensis extract. Thus, zingibroside R1 could be (partly) responsible for the observed health benefits of C. chinensis. Furthermore, a hydroxygallic acid derivative and the sterol lipid 4-alpha-formyl-stigmasta-7,24(241)-dien-3-beta-ol are abundantly present in the C. chinensis extract and its most bioactive fraction, but hardly in E. ulmoides, making them good candidates to explain the overall healthspan benefits of C. chinensis compared to the specific positive effects on stress resistance by E. ulmoides. Our findings highlight the overall anti-aging effects of C. chinensis in C. elegans and provide first hints about the components responsible for these effects.

Toll-Like Receptor 4: A Promising Therapeutic Target for Alzheimer's Disease

Alzheimer's disease (AD) is a progressive neurodegenerative disease that primarily manifests as memory deficits and cognitive impairment and has created health challenges for patients and society. In AD, amyloid β-protein (Aβ) induces Toll-like receptor 4 (TLR4) activation in microglia. Activation of TLR4 induces downstream signaling pathways and promotes the generation of proinflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β), which also trigger the activation of astrocytes and influence amyloid-dependent neuronal death. Therefore, TLR4 may be an important molecular target for treating AD by regulating neuroinflammation. Moreover, TLR4 regulates apoptosis, autophagy, and gut microbiota and is closely related to AD. This article reviews the role of TLR4 in the pathogenesis of AD and a range of potential therapies targeting TLR4 for AD. Elucidating the regulatory mechanism of TLR4 in AD may provide valuable clues for developing new therapeutic strategies for AD.

Pinoresinol diglucoside ameliorates H/R-induced injury of cardiomyocytes by regulating miR-142-3p and HIF1AN

This study is aimed to investigate the effect of pinoresinol diglucoside (PDG) in ameliorating myocardial ischemia-reperfusion injury (MIRI). Hypoxia/reperfusion (H/R)-induced H9c2 cardiomyocytes were used to establish an in-vitro ischemia-reperfusion injury model of cardiomyocytes. Cells were treated with 1 μmol/L of PDG. Reactive oxygen species (ROS) level was detected by a 2',7'-dichlorofluorescein-diacetate assay. The release of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) was examined by enzyme-linked immunosorbent assay. The viability and apoptosis of H9c2 cells were probed by MTT assay and flow cytometry. Besides this, Western blot and quantitative real-time PCR were used to detect microRNA-142-3p (miR-142-3p) and hypoxia-inducible factor 1 subunit alpha inhibitor (HIF1AN) expression levels. The binding sequence between miR-142-3p and HIF1AN 3'-untranslated region was validated by a dual-luciferase reporter gene assay. PDG treatment significantly reduced the level of ROS, LDH, and CK-MB, promoted viability, and inhibited the apoptosis of H9c2 cells. PDG treatment promoted miR-142-3p expression and inhibited HIF1AN expression in H9c2 cells. MiR-142-3p overexpression enhanced the effects of PDG on ROS, LDH, CK-MB levels, cell viability, and apoptosis in H9c2 cardiomyocytes, while overexpression of HIF1AN reversed the above effects. PDG ameliorates H/R-induced injury of cardiomyocytes by regulating miR-142-3p and HIF1AN.

Lignans as Pharmacological Agents in Disorders Related to Oxidative Stress and Inflammation: Chemical Synthesis Approaches and Biological Activities

Plant lignans exhibit a wide range of biological activities, which makes them the research objects of potential use as therapeutic agents. They provide diverse naturally-occurring pharmacophores and are available for production by chemical synthesis. A large amount of accumulated data indicates that lignans of different structural groups are apt to demonstrate both anti-inflammatory and antioxidant effects, in many cases, simultaneously. In this review, we summarize the comprehensive knowledge about lignan use as a bioactive agent in disorders associated with oxidative stress and inflammation, pharmacological effects in vitro and in vivo, molecular mechanisms underlying these effects, and chemical synthesis approaches. This article provides an up-to-date overview of the current data in this area, available in PubMed, Scopus, and Web of Science databases, screened from 2000 to 2022.

Network Pharmacology-Based Prediction and Verification of the Potential Targets of Pinoresinol Diglucoside for OA Treatment

Objective

This study aimed to explore the effects and related mechanisms of pinoresinol diglucoside (PDG) on osteoarthritis (OA) via a combination of pharmacology and animal experiments.

Methods

Traditional Chinese Medicine Database and Analysis Platform (TCMSP) Drugbank, Online Mendelian Inheritance in Man, and GeneCards databases were used to predict the putative targets of PGD against OA. A protein protein interaction (PPI) network was constructed in STING database to analyze the interaction network of these targets. Enrichment analysis was performed with DAVID database. The OA model was built by anterior cruciate ligament transection and then injected with PDG for 5 weeks. Hematoxylin and eosin (HE) staining and safranin-fixed green staining were used to evaluate the pathological change. ELISA was applied to measure the serum levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). Immunohistochemistry was employed to detect the protein levels of kinase B (AKT), BAX, Bcl2, matrix metalloproteinase-1 (MMP-1), tissue inhibitor of metalloproteinases 1 (TIMP-1), and phosphatidylinositol 3 kinase (PI3K) in knee cartilage tissues.

Results

Seventy-one key targets were identified, including AKT1, epidermal growth factor receptor, SRC, estrogen receptor 1 (ESR1), and MMP9. Enrichment analysis revealed a series of pathway related to cancer, PI3K-Akt signaling pathway, and proteoglycans in cancer. Animal experiments showed that PDG alleviated the abnormal histomorphological changes of OA; suppressed TIPM, serum IL-1β, IL-6, and TNF-α levels, and PI3K and AKT activation; and increased MMP-1 expression and Bcl2/Bax ratio.

Conclusion

PDG has a cartilage-protecting effect associated with PI3K/AKT signaling pathway in rabbit with OA and therefore might serve as a potential agent for the treatment of this disease.

Dendrobine modulates autophagy to alleviate ox-LDL-induced oxidative stress and senescence in HUVECs

Dendrobine has potential advantages in suppressing atherosclerosis (AS). FK506-binding protein 1A (FKBP1A) is implicated in the regulation of autophagy, inflammation, and apoptosis. To reveal the mechanism by which dendrobine inhibits AS by modulating autophagy, oxidative stress, apoptosis, and senescence. An in vitro AS cell model was induced by culturing human umbilical vein endothelial cells (HUVECs) with oxidized low-density lipoprotein (ox-LDL). The cells were treated with dendrobine alone or in combination with short hairpin RNA (shRNA) targeting FKBP1A or together with 3-methyladenine (3MA), an autophagy inhibitor. Inflammatory cytokines levels tumor necrosis factor-α, interleukin-6 (IL-6), and IL-1β were analyzed and oxidative stress levels were detected by the analysis of reactive oxygen species, malondialdehyde, and superoxide dismutase levels, followed by the analysis of apoptosis levels through terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Cell senescence was evaluated by senescence-associated β-galactosidase and light chain 3 (LC3) levels were detected by immunofluorescence (IF) staining. The targeting relationship of dendrobine and FKBP1A was predicted by SwissTarget, PyMol, Autodock, and Open Babel software. Dendrobine reduced the levels of proinflammation factors, oxidative stress levels, apoptosis levels, and senescence phenotype in ox-LDL-induced HUVECs. Besides, cell viability has an opposite change. Furthermore, there was an increase in LC3 IF tensity, and LC3-II/I and Beclin1 expressions, and a decrease in p62 expression. However, these effects of dendrobine could be markedly destroyed by shRNA silencing FKBP1A and 3MA. Dendrobine can suppress inflammatory responses, oxidative stress, apoptosis, and senescence via FKBP1A-involved autophagy ox-LDL-treated HUVECs.

Small, Dense Low-Density Lipoprotein-Cholesterol and Atherosclerosis: Relationship and Therapeutic Strategies

Low-density lipoprotein cholesterol (LDL-C) plays an important role in the formation, incidence, and development of atherosclerosis (AS). Low-density lipoproteins can be divided into two categories: large and light LDL-C and small, dense low-density lipoprotein cholesterol (sdLDL-C). In recent years, an increasing number of studies have shown that sdLDL-C has a strong ability to cause AS because of its unique characteristics, such as having small-sized particles and low density. Therefore, this has become the focus of further research. However, the specific mechanisms regarding the involvement of sdLDL-C in AS have not been fully explained. This paper reviews the possible mechanisms of sdLDL-C in AS by reviewing relevant literature in recent years. It was found that sdLDL-C can increase the atherogenic effect by regulating the activity of gene networks, monocytes, and enzymes. This article also reviews the research progress on the effects of sdLDL-C on endothelial function, lipid metabolism, and inflammation; it also discusses its intervention effect. Diet, exercise, and other non-drug interventions can improve sdLDL-C levels. Further, drug interventions such as statins, fibrates, ezetimibe, and niacin have also been found to improve sdLDL-C levels.

Protective Effect of Flavonoids from a Deep-Sea-Derived Arthrinium sp. against ox-LDL-Induced Oxidative Injury through Activating the AKT/Nrf2/HO-1 Pathway in Vascular Endothelial Cells

Oxidized low-density lipoprotein (ox-LDL)-induced oxidative injury in vascular endothelial cells is crucial for the progression of cardiovascular diseases, including atherosclerosis. Several flavonoids have been shown cardiovascular protective effects. Recently, our research group confirmed that the novel flavonoids isolated from the deep-sea-derived fungus Arthrinium sp., 2,3,4,6,8-pentahydroxy-1-methylxanthone (compound 1) and arthone C (compound 2) effectively scavenged ROS in vitro. In this study, we further investigated whether these compounds could protect against ox-LDL-induced oxidative injury in endothelial cells and the underlying mechanisms. Our results showed that compounds 1 and 2 inhibited ox-LDL-induced apoptosis and adhesion factors expression in human umbilical vein vascular endothelial cells (HUVECs). Mechanistic studies showed that these compounds significantly inhibited the ROS level increase and the NF-κB nuclear translocation induced by ox-LDL. Moreover, compounds 1 and 2 activated the Nrf2 to transfer into nuclei and increased the expression of its downstream antioxidant gene HO-1 by inducing the phosphorylation of AKT in HUVECs. Importantly, the AKT inhibitor MK-2206 2HCl or knockdown of Nrf2 by RNA interference attenuated the inhibition effects of these compounds on ox-LDL-induced apoptosis in HUVECs. Meanwhile, knockdown of Nrf2 abolished the effects of the compounds on ox-LDL-induced ROS level increase and the translocation of NF-κB to nuclei. Collectively, the data showed that compounds 1 and 2 protected endothelial cells against ox-LDL-induced oxidative stress through activating the AKT/Nrf2/HO-1 pathway. Our study provides new strategies for the design of lead compounds for related cardiovascular diseases treatment.

Pinoresinol diglucoside alleviates ischemia/reperfusion-induced brain injury by modulating neuroinflammation and oxidative stress

Brain ischemia/reperfusion (I/R) injury is a common pathological process after ischemic stroke. Pinoresinol diglucoside (PDG) has antioxidation and anti-inflammation activities. However, whether PDG ameliorates brain I/R injury is still unclear. In this study, middle cerebral artery occlusion (MCAO) model was established with male C57BL/6 mice, and the mice were treated with 5 and 10 mg/kg PDG via intravenous injection, respectively. The neurological deficit, infarct volume, and brain water content were then evaluated. HE staining and Nissl staining were used to analyze neuron injury. Besides, enzyme-linked immunosorbent assay and colorimetry assay were used to examine the level of inflammatory markers and oxidative stress markers, and Western blot was used to detect the expressions of p-p65, Nrf2, and HO-1. It was revealed that PDG could significantly alleviate the MCAO-induced neurological dysfunction of the mice and reduce the infarct volume, brain water content, and neuron injury. PDG treatment decreased the levels of TNF-α, IL-1β, IL-6, NO, ROS, and MDA, and significantly increased the activities of SOD, GSH, and GSH-Px in the brain tissue of the mice. Additionally, PDG could repress the activation of p65 and promote Nrf2 and HO-1 expressions. In conclusion, PDG exerts anti-inflammatory and antioxidation effects via regulating the NF-κB pathway and Nrf2/HO-1 pathway, thereby reducing the I/R-induced brain injury of mice.

Long Non-Coding RNA, Small Nucleolar RNA Host Gene 5, Inhibits the Oxidized Low-Density Lipoprotein Induced Vascular Endothelial Cell Injury by Targeting miR-26a-5p

Atherosclerosis is the major cause of cardiovascular disease, and endothelial cell injury is the primary atherogenic factor. Long non-coding RNAs (lncRNAs) are increasingly implicated as critical regulators of disease progression. Still, the role of lncRNA in endothelial cell injury is largely unknown. This issue was explored in control, ox-LDL stimulated, ox-LDL stimulated+transfected negative control vector, and ox-LDL stimulated+SNHG5 overexpression vector EA. hy926 cells. Quantitative real-time PCR used to assess the expression of SNHG5 and miR-26a-5p. Flow cytometry was used to evaluate cell apoptosis. Activity or concentration of SOD, MDA, CAT, and reactive oxygen species (ROS) was measured to assess oxidative stress. Western blotting was used to examine protein-level expression of cleaved Caspase-3, cleaved Caspase-9, and cyt-c in cytoplasm and mitochondria. Potential binding sites between SNHG5 and miR-26a-5p were predicted using Starbase software, and dual-luciferase reporter assays were used to identify target relationships. SNHG5 expression in cells following ox-LDL treatment was downregulated in EA. hy926 cells. Ox-LDL treatment promotes apoptosis, and increased C-Caspase-3, C-Caspase-9, and cytoplasmic cyt-c protein levels. MDA concentration and ROS activity were increased, while the activity of SOD and CAT was decreased. Transfection with SNHG5 reversed the effects of ox-LDL on cell apoptosis and oxidative stress. SNHG5 targeted miR-26a-5p and regulated its expression. miR-26a-5p mimics reversed SNHG5 modulation of apoptosis and oxidative stress. lncRNA SNHG5 targets to miR-26a-5p to regulate vascular endothelial cell injury induced by ox-LDL.

Matrix Metalloproteinase-7 Aggravated the Oxidized Low Density Lipoprotein-Induced Damage of Human Vascular Endothelial Cells

Introduction: Vascular endothelial injury could induce many cardiovascular diseases. Recently, some studies have indicated that matrix metalloproteinase-7 (MMP-7) was associated with the occurrence and development of cardiovascular diseases. However, whether higher levels of MMP-7 were associated with the occurrence of the vascular endothelial injury is unclear. Material and methods: In this study, ox-LDL was used for the simulation of vascular endothelial injury in HUVECs. Next, we detected the expression of MMP-7 in these cells. After that, we established the cell models with MMP-7 overexpression and knockdown, respectively. At last, the apoptosis and inflammation of HUVECs were detected with corresponding assays. Results: After the stimulation of ox-LDL, the expression of MMP-7 was enhanced compared to the control groups. After the stimulation of ox-LDL and the overexpression of MMP-7, the apoptosis rates of HUVECs were enhanced, while MMP-7 knockdown led to the decreased apoptosis rates of these cells. Furthermore, after the stimulation of ox-LDL and overexpression of MMP-7, the expression of inflammatory factors (IL-6, IL-1β and TNF-α) was promoted. Additionally, the expression of these proteins was repressed after knockdown of MMP-7. Conclusion: MMP-7 aggravated the ox-LDL-induced damage of HUVECs by promoting the apoptosis and inflammation of these cells.

Genomic-Wide Identification and Characterization of the Uridine Diphosphate Glycosyltransferase Family in Eucommia ulmoides Oliver

Eucommia ulmoides Oliver is a woody plant with great economic and medicinal value. Its dried bark has a long history of use as a traditional medicinal material in East Asia, which led to many glycosides, such as aucubin, geniposide, hyperoside, astragalin, and pinoresinol diglucoside, being recognized as pharmacologically active ingredients. Uridine diphosphate glycosyltransferases (UGTs) catalyze a glycosyl-transferring reaction from the donor molecule uridine-5'-diphosphate-glucose (UDPG) to the substrate, which plays an important role in many biological processes, such as plant growth and development, secondary metabolism, and environmental adaptation. In order to explore the biosynthetic pathways of glycosides in E. ulmoides, 91 putative EuUGT genes were identified throughout the complete genome of E. ulmoides through function annotation and an UDPGT domain search. Phylogenetic analysis categorized them into 14 groups. We also performed GO annotations on all the EuUGTs to gain insights into their functions in E. ulmoides. In addition, transcriptomic analysis indicated that most EuUGTs showed different expression patterns across diverse organs and various growing seasons. By protein-protein interaction predication, a biosynthetic routine of flavonoids and their glycosides was also proposed. Undoubtedly, these results will help in future research into the biosynthetic pathways of glycoside compounds in E. ulmoides.

Pinoresinol diglucoside (PDG) attenuates cardiac hypertrophy via AKT/mTOR/NF-κB signaling in pressure overload-induced rats

ETHNOPHARMACOLOGICAL RELEVANCE

Pinoresinol diglucoside (PDG), the active compound extracted from Eucommia ulmoides, Styrax sp. and Forsythia suspensa, plays the roles in regulating hypertension, inflammation and oxidative stress.

AIMS

Considering that hypertension and inflammation has been proved to contribute to cardiac remodeling, we tested the effects of PDG on cardiac hypertrophy (CM).

METHODS

Male Sprague Dawley (SD) rats were used to construct hypertrophic rats by partial abdominal aortic constriction (AAC)-surgery. PDG solution (2 mg/ml) was used to treat AAC-induced rats by intraperitoneal injection at low dose (L-PDG, 2.5 mg/kg per day), medium dose (M-PDG, 5 mg/kg per day), and high dose (H-PDG, 7.5 mg/kg per day) for 3 weeks post AAC-surgery. CM was evaluated by the ratio of left ventricular weight to body weight ratio (LVW/BW), left ventricular wall thickness by H&E staining, and collagen content deposit by Masson's staining. Further, isoproterenol (ISO) and phenylephrine (PE) were used to produce cellular models of CM in neonatal rat ventricular cardiomyocytes (NRVMs). PDG pre-treated NRVMs 2 h at low dose (L-PDG, 2.5 μg/ml), medium dose (M-PDG, 5 μg/ml), and high dose (H-PDG, 7.5 μg/ml) for 24 h with or without PE- and ISO-stimulation. CM was evaluated by the expressions of hypertrophic biomarkers. Next, the hypertrophic biomarkers and pro-inflammatory cytokines were measured using quantitative real-time PCR (qRT-PCR), the expressions of protein kinase B (AKT)/mammalian target of rapamycin (mTOR)/transcription factor nuclear factor-kappa B (NF-kB) signaling pathway were determined by Western blotting.

RESULTS

PDG treatment prevented cardiac histomorphology damages, decreased upregulations of hypertrophic biomarkers, and prevented fibrosis and inflammation after pressure overload resulting from AAC-surgery. Consistently, PDG remarkably inhibited the changes of cardiomyocyte hypertrophic biomarkers and inflammatory responses in cellular models of CM. Interestingly, PDG administration inhibited the activation of AKT/mTOR/NF-kB signaling pathway both in vivo and in vitro.

CONCLUSIONS

PDG prevents AAC-induced CM in vivo, PE- and ISO-induced CM in vitro. The AKT/mTOR/NF-kB signaling pathway could be the potential therapeutic target involved in the protection of PDG. These findings provide novel evidence that PDG might be a promising therapeutic strategy for CM.

Lignans of Sesame (Sesamum indicum L.): A Comprehensive Review

Major lignans of sesame sesamin and sesamolin are benzodioxol--substituted furofurans. Sesamol, sesaminol, its epimers, and episesamin are transformation products found in processed products. Synthetic routes to all lignans are known but only sesamol is synthesized industrially. Biosynthesis of furofuran lignans begins with the dimerization of coniferyl alcohol, followed by the formation of dioxoles, oxidation, and glycosylation. Most genes of the lignan pathway in sesame have been identified but the inheritance of lignan content is poorly understood. Health-promoting properties make lignans attractive components of functional food. Lignans enhance the efficiency of insecticides and possess antifeedant activity, but their biological function in plants remains hypothetical. In this work, extensive literature including historical texts is reviewed, controversial issues are critically examined, and errors perpetuated in literature are corrected. The following aspects are covered: chemical properties and transformations of lignans; analysis, purification, and total synthesis; occurrence in Seseamum indicum and related plants; biosynthesis and genetics; biological activities; health-promoting properties; and biological functions. Finally, the improvement of lignan content in sesame seeds by breeding and biotechnology and the potential of hairy roots for manufacturing lignans in vitro are outlined.

Pinoresinol diglucoside attenuates neuroinflammation, apoptosis and oxidative stress in a mice model with Alzheimer's disease

For Alzheimer's disease (AD), there is still no effective treatment strategy. Pinoresinol diglucoside (PDG) is one of the major lignans isolated from Eucommia ulmoides. It is endowed with multiple pharmacological activities, including anti-inflammatory, antioxidant and anticancer activities. In this study, we investigated the potential neuroprotective functions of PDG in AD. Mice model with AD was established adopting stereotactic hippocampal injection of Aβ1-42 (410 pmol/mouse), and 3 days later, mice were administrated with 5 and 10 mg/kg PDG by intragastric administration every day for 3 weeks. Morris water maze and Y-maze tests demonstrated that PDG treatment could markedly reverse Aβ1-42-induced memory impairment in mice. It is found that PDG restrained the release of proinflammatory cytokines (tumor necrosis factor α and interleukin 1β), reactive oxygen species and malondialdehyde, and promoted the activity of the antioxidant enzyme (superoxide dismutase and catalase) by quantitative real-time-PCR, colorimetric method and ELISA assay. Western blot assay results have shown that PDG could also upregulate the ratio of Bcl-2/Bax and downregulate cytochrome c and cleaved caspase-3 expressions, thereby inhibiting neuronal apoptosis. Furthermore, PDG also significantly reduced the expression of Toll-like receptor 4 (TLR4) and the activation of nuclear factor-κB (NF-κB) p65, and promoted nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) expressions. In conclusion, PDG can attenuate neuroinflammation, neuronal apoptosis and oxidative stress through the TLR4/NF-κB and Nrf2/HO-1 pathways, and ameliorate memory dysfunction induced by Aβ1-42 in mice.

Chemical Constituents of the Leaves of Campanula takesimana (Korean Bellflower) and Their Inhibitory Effects on LPS-induced PGE2 Production

Campanula takesimana Nakai (Campanulaceae; Korean bellflower) is one of the endemic herbs of Korea. The plant has been used as traditional medicines for treating asthma, tonsillitis, and sore throat in Korea. A hot water extract of the leaves of C. takesimana exhibited a significant inhibitory effect on lipopolysaccharide (LPS)-stimulated prostaglandin E₂ (PGE₂) production. Repetitive chromatographic separation of the hot water extract led to the isolation of three new neolignan glucosides, campanulalignans A-C (1-3), with 15 known compounds (4-18). The structures of new compounds 1-3 were elucidated by analyzing nuclear magnetic resonance (NMR) spectroscopic data, along with high resolution quadrupole time of flight mass (HR-Q-TOF-MS) spectrometric data. Among the isolates, simplidin (7), 5-hydroxyconiferaldehyde (11), icariside F₂ (12), benzyl-α-l-arabinopyranosyl-(1″→6')-β-d-glucopyranoside (13), and kaempferol 3-O-β-d-apiosyl (1→2)-β-d-glucopyranoside (15) were isolated from the Campanulaceae family for the first time. The isolates (1, 2, and 4-18) were assessed for their anti-inflammatory effects on LPS-stimulated PGE₂ production on RAW 264.7 cells. 7R,8S-Dihydrodehydrodiconiferyl alcohol (5), 3',4-O-dimethylcedrusin 9-O-β-glucopyranoside (6), pinoresinol di-O-β-d-glucoside (8), ferulic acid (10), 5-hydroxyconiferaldehyde (11), and quercetin (18) showed significant inhibitory effects on LPS-stimulated PGE₂ production.

Downregulation of LncRNA NORAD promotes Ox-LDL-induced vascular endothelial cell injury and atherosclerosis

Long noncoding RNAs (lncRNAs) play important roles in the development of vascular diseases. However, the effect of lncRNA NORAD on atherosclerosis remains unknown. This study aimed to investigate the effect NORAD on endothelial cell injury and atherosclerosis. Ox-LDL-treated human umbilical vein endothelial cells (HUVECs) and high-fat-diet (HFD)-fed ApoE^−/− mice were used as in vitro and in vivo models. Results showed that NORAD-knockdown induced cell cycle arrest in G0/G1 phase, aggravated ox-LDL-induced cell viability reduction, cell apoptosis, and cell senescence along with the increased expression of Bax, P53, P21 and cleaved caspase-3 and the decreased expression of Bcl-2. The effect of NORAD on cell viability was further verified via NORAD-overexpression. NORAD- knockdown increased ox-LDL-induced reactive oxygen species, malondialdehyde, p-IKBα expression levels and NF-κB nuclear translocation. Proinflammatory molecules ICAM, VCAM, and IL-8 were also increased by NORAD- knockdown. Additionally, we identified the strong interaction of NORAD and IL-8 transcription repressor SFPQ in HUVECs. In ApoE^−/− mice, NORAD-knockdown increased the lipid disorder and atherosclerotic lesions. The results have suggested that lncRNA NORAD attenuates endothelial cell senescence, endothelial cell apoptosis, and atherosclerosis via NF-κB and p53–p21 signaling pathways and IL-8, in which NORAD-mediated effect on IL-8 might through the direct interaction with SFPQ.