Plantamajoside attenuates cardiac fibrosis via inhibiting AGEs activated-RAGE/autophagy/EndMT pathway.

Advanced glycation end products (AGEs) have been identified to transduce fibrogenic signals via inducing the activation of their receptor (RAGE)-mediated pathway. Recently, disrupting AGE-RAGE interaction has become a promising therapeutic strategy for chronic heart failure (CHF). Endothelial-to-mesenchymal transition (EndMT) is close to the cardiac fibrosis pathological process. Our previous studies have demonstrated that knockout RAGE suppressed the autophagy-mediated EndMT, and thus alleviated cardiac fibrosis. Plantamajoside (PMS) is the major bioactive compound of Plantago Asiatica, and its activity of anti-fibrosis has been documented in many reports. However, its effect on CHF and the underlying mechanism remains elusive. Thus, we tried to elucidate the protective role of PMS in CHF from the viewpoint of the AGEs/RAGE/autophagy/EndMT axis. Herein, PMS was found to attenuate cardiac fibrosis and dysfunction, suppress EndMT, reduce autophagy levels and serum levels of AGEs, yet did not affect the expression of RAGE in CHF mice. Mechanically, PMS possibly binds to the V-domain of RAGE, which is similar to the interaction between AGEs and RAGE. Importantly, this competitive binding disturbed AGEs-induced the RAGE-autophagy-EndMT pathway in vitro. Collectively, our results indicated that PMS might exert an anti-cardiac fibrosis effect by specifically binding RAGE to suppress the AGEs-activated RAGE/autophagy/EndMT pathway.

Plantamajoside protects H9c2 cells against hypoxia/reoxygenation-induced injury through regulating the akt/Nrf2/HO-1 and NF-κB signaling pathways.

Myocardial ischemia/reperfusion (I/R) injury has been found to be associated with oxidative stress. Plantamajoside (PMS) is a major compound of Plantago asiatica that was reported to possess cardioprotective and antioxidant effects. The current study was designed to investigate the effect of PMS on myocardial I/R injury. Rat cardiomyocytes H9c2 cells were exposed to hypoxia/reoxygenation (H/R) to establish in vitro model of myocardial I/R injury. MTT assay proved that H9c2 cells viability was significant reduced under H/R treatment, while the reduction was ameliorated by PMS. H/R-induced ROS production in H9c2 cells was suppressed by PMS. The decreased activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in the H/R group were effectively elevated by PMS. In addition, treatment with PMS attenuated H/R-stimulated production of TNF-α, IL-6 and IL-1ß in H9c2 cells. Besides, PMS significantly suppressed bax expression and caspase 3 activity, as well as increased bcl-2 expression in H/R-stimulated H9c2 cells. Furthermore, we also found that PMS significantly enhanced the activation of Akt/Nrf2/HO-1 signaling pathway and suppressed the activation of NF-κB signaling pathway in H/R-stimulated H9c2 cells. These results provided substantial evidence that PMS protected against myocardial I/R injury via attenuating oxidative stress, inflammatory response and apoptosis. The protective effects of PMS were attributed to the Akt/Nrf2/HO-1 and NF-κB signaling pathways.

Exploration of a ternary deep eutectic solvent for the efficient extraction of plantamajoside, acteoside, quercetin and kaempferol from Plantago asiatica L.

INTRODUCTION: In the present study, ternary deep eutectic solvent-based ultrasound-assisted extraction was developed for the efficient extraction of plantamajoside, acteoside, quercetin and kaempferol from Plantago asiatica L. METHODOLOGY: Six kinds of choline chloride-based ternary deep eutectic solvents (TDESs) were prepared as potential extraction solutions. In order to obtain optimal extraction efficiency, a series of extraction conditions were investigated by single-factor test and orthogonal test. RESULTS: The extraction efficiency of choline chloride/lactic acid/ethylene glycol (ChCl-LA-EG) was much higher than that of other TDESs. ChCl-LA-EG-11 synthesised with choline chloride, lactic acid and ethylene glycol (1:4:2) was considered to have a higher extraction efficiency. The optimal ultrasound-assisted extraction conditions were as follows: water content in ChCl-LA-EG-11, 50%; extraction temperature, 70°C; ratio of solid/liquid, 20 mg/mL; ultrasonic power, 60 W; extraction time, 35 min; pH of the solution, 8. Under the optimal extraction conditions, the extraction efficiencies of plantamajoside, acteoside, quercetin and kaempferol were 3.83 ± 0.41, 4.23 ± 0.45, 0.56 ± 0.15 and 0.19 ± 0.08 mg/g, respectively. The extraction efficiency of the total target components was 9.21 ± 0.63 mg/g, which was much higher than that of conventional solvents (water, methanol, ethanol, 50% methanol, 50% ethanol). The target components were isolated efficiently from the TDES solution by an AB-8 macroporous resin column with a recovery rate of 95.6%. CONCLUSION: This study demonstrated that TDESs possessed excellent physical and chemical properties and had enormous potential for active component extraction of traditional Chinese medicinal materials.

Plantamajoside inhibits hypoxia-induced migration and invasion of human cervical cancer cells through the NF-κB and PI3K/akt pathways.

Plantamajoside (PMS) is a major compound of Plantago asiatica and possesses anti-tumor property in several types of cancers. However, the effect of PMS on cervical cancer has not been investigated. This study aimed to investigate the effect of PMS on the migration and invasion of cervical cancer cell lines under hypoxic condition. Our results demonstrated that PMS significantly inhibited hypoxia-caused increases in cell migration and invasion of cervical cancer cells. The hypoxia-induced epithelial-mesenchymal transition (EMT) process was prevented by PMS with increased E-cadherin expression, and decreased expression levels of N-cadherin and vimentin in cervical cancer cells. Besides, the expression levels of transcription factors slug and snail were suppressed by PMS in hypoxia-induced cervical cancer cells. The increased mRNA and protein levels of hypoxia-inducible factor 1alpha (HIF-1α) in hypoxia-induced cervical cancer cells were prevented by PMS. Furthermore, PMS blocked the hypoxia-induced activation of NF-κB and PI3K/Akt pathway in cervical cancer cells. Taken together, these findings suggest that PMS exerted an anti-tumor activity in cervical cancer through preventing the hypoxia-induced EMT. Thus, PMS might serve as a therapeutic agent for the treatment of cervical cancer.

Plantamajoside inhibits high glucose-induced oxidative stress, inflammation, and extracellular matrix accumulation in rat glomerular mesangial cells through the inactivation of Akt/NF-κB pathway.

Plantamajoside (PMS) is a phenylpropanoid glycoside that possesses anti-diabetic activity. However, the effect of PMS on diabetic nephropathy (DN) has not been investigated. This study aimed to evaluate the role of PMS in DN and the potential mechanism. The rat glomerular mesangial cells ((MCs) (HBZY-1 cells) were cultured under high glucose (HG) condition or normal condition with or without the treatment of PMS. The results showed that PMS ameliorated the cell injury that was induced by HG in HBZY-1 cells. The HG-caused increases in reactive oxygen species (ROS) and malondialdehyde (MDA) production and decrease in superoxide dismutase (SOD) activity were prevented by PMS. The qRT-PCR and ELISA assays demonstrated an anti-inflammatory activity of PMS, as evidenced by decreased levels of TNF-α, IL-1ß, and IL-6 in HG-induced HBZY-1 cells. Moreover, the increased levels of fibronectin (FN) and collagen type IV (Col IV) in HBZY-1 cells caused by HG were also reduced by PMS treatment. Furthermore, PMS significantly suppressed HG-induced activation of Akt/NF-κB signaling in HBZY-1 cells. Taken together, these findings indicated that PMS alleviated HG-induced injury in HBZY-1 cells through suppressing oxidative stress, inflammatory response, and extracellular matrix (ECM) accumulation via the inactivating Akt/NF-κB pathway. Thus, PMS might possess potential capacity for the treatment of DN.

Tissue-Specific Accumulation and Isomerization of Valuable Phenylethanoid Glycosides from Plantago and Forsythia Plants.

A comparative phytochemical study on the phenylethanoid glycoside (PhEG) composition of the underground organs of three Plantago species (P. lanceolata, P. major, and P. media) and that of the fruit wall and seed parts of Forsythia suspensa and F. europaea fruits was performed. The leaves of these Forsythia species and six cultivars of the hybrid F. × intermedia were also analyzed, demonstrating the tissue-specific accumulation and decomposition of PhEGs. Our analyses confirmed the significance of selected tissues as new and abundant sources of these valuable natural compounds. The optimized heat treatment of tissues containing high amounts of the PhEG plantamajoside (PM) or forsythoside A (FA), which was performed in distilled water, resulted in their characteristic isomerizations. In addition to PM and FA, high amounts of the isomerization products could also be isolated after heat treatment. The isomerization mechanisms were elucidated by molecular modeling, and the structures of PhEGs were identified by nuclear magnetic resonance spectroscopy (NMR) and high-resolution mass spectrometry (HR-MS) techniques, also confirming the possibility of discriminating regioisomeric PhEGs by tandem MS. The PhEGs showed no cytostatic activity in non-human primate Vero E6 cells, supporting their safe use as natural medicines and allowing their antiviral potency to be tested.

Plantamajoside inhibits the proliferation and epithelial-to-mesenchymal transition in hepatocellular carcinoma cells via modulating hypoxia-inducible factor-1α-dependent gene expression.

As a potential antitumor herbal medicine, plantamajoside (PMS) benefits the treatment of many human malignances. However, the role of PMS in the progression of hepatocellular carcinoma (HCC) and the related molecular mechanisms is still unknown. Here, we proved that the cell viabilities of HepG2 cells were gradually decreased with the increasing concentrations of CoCl2 and/or PMS via cell counting kit-8 assay. Meanwhile, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and western blot assays were used to further confirm that PMS inhibited the CoCl2 -induced cell proliferation in HepG2 cells via suppressing the Ki67 and proliferating cell nuclear antigen expressions. We also performed wound-healing and transwell assays and demonstrated that PMS inhibited CoCl2 -induced migration and invasion in HepG2 cells via suppressing the epithelial-mesenchymal transition (EMT) process. In addition, the use of 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole further proved that PMS inhibited the malignant biological behaviors of HepG2 cells under hypoxic condition by suppressing the hypoxia-inducible factor-1α (HIF-1α) expression. Besides, we further confirmed that PMS suppressed the growth and metastasis of implanted tumors in vivo. Given that PMS suppressed the proliferation and EMT induced by CoCl2 in HCC cells via downregulating HIF-1α signaling pathway, we provided evidence that PMS might be a novel anti-cancer drug for HCC treatment.

Plantamajoside attenuates inflammatory response in LPS-stimulated human gingival fibroblasts by inhibiting PI3K/AKT signaling pathway.

Periodontitis is an important inflammatory disease that often causes by periodontopathic bacteria. The present study, we tested the anti-inflammatory effects of plantamajoside on LPS-stimulated human gingival fibroblasts. Human gingival fibroblasts (HGFs) were stimulated with LPS from Porphyromonas gingivalis. Plantamajoside was administrated 1 h before LPS treatment. The results demonstrated that plantamajoside decreased the production of PGE2, NO, IL-6, and IL-8 in LPS-stimulated HGFs. LPS-induced NF-κB p65 and IκB phosphorylation were also suppressed by plantamajoside. Furthermore, plantamajoside inhibited LPS-induced PI3K and AKT phosphorylation. In conclusion, these results suggested that the mechanism of plantamajoside was through inhibiting PI3K/AKT signaling pathway, which lead to the inhibition of NF-κB activation and inflammatory response.

UHPLC-MS/MS determination and pharmacokinetic study of plantamajoside in rat plasma after oral administration of single plantamajoside and Plantago asiatica extract.

A sensitive and reliable ultra-high performance liquid chromatography coupled with tandem quadrupole mass spectrometry (UHPLC-MS/MS) method was developed for quantitation of plantamajoside in rat plasma. First, this study compared the pharmacokinetic properties of plantamajoside after oral administration of Plantago asiatica extract and pure plantamajoside in rat plasma with approximately the same dosage of 8.98 mg/kg. Second, chromatographic separation was performed on an Acquity HSS C18 column (50 × 2.1 mm, p.d.1.7 µm) with isocratic elution using methanol-water (80:20, v/v) as mobile phase at a flow rate of 0.25 mL/min. The calibration curves were linear over the range of 0.1-100 ng/mL for plantamajoside. At different time points (0, 0.083, 0.167, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6 and 8 h) after administration, the concentrations of plantamajoside in plasma were measured and the main pharmacokinetic parameters were estimated. The study indicates that the pharmacokinetics of plantamajoside in rat plasma have significant differences between two groups.

Plantamajoside from Plantago asiatica modulates human umbilical vein endothelial cell dysfunction by glyceraldehyde-induced AGEs via MAPK/NF-κB.

BACKGROUND: Plantago asiatica has been traditionally used for traditional medicine around East Asia. Plantamajoside (PM), which is isolated from this plant, is known for biological properties including anti-inflammation and antioxidant activity. To demonstrate the biological activity of PM against endothelial dysfunction induced by advanced glycation end-products (AGEs), a cellular inflammatory mechanism system was evaluated in human umbilical vein endothelial cells (HUVECs). METHODS: We obtained PM through previous research in our laboratory. We formed the AGEs from bovine serum albumin with glyceraldehyde in the dark for seven days. To confirm the modulation of the inflammatory mechanism in endothelial dysfunction, we quantified the various pro-inflammatory cytokines and endothelial dysfunction-related proteins in the HUVECs with Western blotting and with real-time and quantitative real-time polymerase chain reactions. RESULTS: Co-treatment with PM and AGEs significantly suppressed inflammatory cytokines and adhesion molecule expression. Moreover, the PM treatment for down-regulated inflammatory signals and blocked monocyte adhesion on the HUVECs. CONCLUSIONS: Theses results demonstrated that PM, as a potential natural compound, protects AGE-induced endothelial cells against inflammatory cellular dysfunction.

Chemical Profiling and Assessment of Antineurodegenerative and Antioxidant Properties of Veronica teucrium L. and Veronica jacquinii Baumg.

Neuroprotective potential of V. teucrium and V. jacquinii methanol extracts was analyzed. Chemical analysis of investigated extracts showed the presence of phenolic acid derivatives, flavonoids and one secoiridoid. The detected flavonoids derived from flavones (luteolin and isoscutellarein in V. jacquinii; apigenin, isoscutellarein and luteolin in V. teucrium) and flavonol (quercetin in V. jacquinii). Acteoside was the dominant compound in V. jacquinii, while plantamajoside and isoscutellarein 7-O-(6‴-O-acetyl)-ß-allosyl (1‴→2‴)-ß-glucoside were the major phenolics in V. teucrium. Additionally, the antineurodegenerative activity was tested at concentrations of 25, 50, and 100 µg/ml using acetylcholinesterase (AChE) and tyrosinase (TYR) assays. The inhibition of both enzymes was achieved with the investigated extracts, ranging from 22.78 to 35.40% for AChE and from 9.57 to 16.38% for TYR. There was no statistical difference between the activities of the analyzed extracts. Our data indicate that V. teucrium and V. jacquinii may have beneficial effects against Alzheimer's and Parkinson's disease.

C-X-C motif chemokine receptor 4 inhibition promotes the effect of plantamajoside in hepatocellular carcinoma.

BACKGROUND AND STUDY AIM: Hepatocellular carcinoma (HCC) is the fifth leading cause of cancer-related mortality worldwide, and, more than half of these cases are diagnosed in China. However, effective treatment for HCC is still limited. MATERIAL AND METHODS: C-X-C motif chemokine receptor 4 (CXCR4) was first activated and inhibited in HepG2 cells using a pharmacological method. HepG2 cell proliferation was detected using the CCK-8 method. Metastasis and apoptosis of HepG2 cells were detected using wound healing and flow cytometry. The expression of each target molecule related to metastasis and invasion, such as MMPs, E-cadherin and the PI3K/AKT/Mcl-1/PARP signaling pathway was detected by western blotting. The secretion of molecular metastases was detected using competitive ELISA. RESULTS: This study constructed a CXCR4 activation and inhibition model in HepG2 cells. CXCR4 inhibition promoted the inhibitory effect of plantamajoside on the proliferation and metastasis of cells, which led to apoptosis. Furthermore, we found that the expression of apoptosis-related proteins was increased after treatment with plantamajoside combined with CXCR4 inhibition. In addition, the expression and secretion of pro-metastatic proteins, including MMPs and E-cadherin were decreased. We also noticed that this effect might be mediated by the PI3K/AKT/Mcl-1/PARP signaling pathway. CONCLUSION: CXCR4 inhibition may contribute to the treatment of HCC. Inhibition of CXCR4 expression contributes to the therapeutic effect of plantamajoside; the effect of plantamajoside might be mediated by the PI3K/AKT/Mcl-1/PARP signaling pathway; and CXCR4 might be a therapeutic target of HCC.

Plantamajoside suppresses the activation of NF-κB and MAPK and ameliorates the development of osteoarthritis.

Osteoarthritis (OA) is a common degenerative bone and joint disorder characterized by progressive cartilage degeneration and secondary synovial inflammation. It is a common chronic joint disorder that affects people of all ages (especially the old). Plantamajoside is a phenylpropanoside derived from plantain. It has a variety of biological properties, including antioxidant, anti-malignant cell proliferation, and anti-inflammatory properties. In this study, the latent mechanism of plantamajoside was explored by slowing the in-vivo and in-vitro progression of osteoarthritis. The results revealed that plantamajoside pre-conditioning inhibited IL-1ß induced pro-inflammatory factors like COX-2, iNOS, IL-6, and TNF-α. Moreover, plantamajoside also reversed the IL-1 ß mediated type II collagen and aggrecan degradation within the extracellular matrix (ECM). The protective effects of plantamajoside have been attributed to the inhibition of both MAPK and NF-κB pathways. Furthermore, our in-vivo research found that plantamajoside could slow the progression of OA in mice. Finally, all findings point to plantamajoside as a potential anti-OA therapeutic candidate.

Cytotoxic Effect of Phenylethanoid Glycosides Isolated from Plantago lanceolata L.

The aim of the study is to investigate whether the bioactive compounds isolated from P. lanceolata inflorescences, namely, phenylethanoid glucosides, acteoside, plantamajoside, and a flavonoid, isorhamnetin-3-O-rutinoside-4'-O-glucoside, possessed cytotoxic activity against the selected cancer cell lines. The potential antitumor effects of two phenylethanoid glycosides and one flavonoid were evaluated via MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on seven human carcinoma cell lines (MCF-7, MDA-MB-231, Caco-2, HepG2, OVCAR-3, U138-MG, U251-MG) and one nontumorigenic mammary epithelial cell line (MCF-12A). For the first time, acteoside was studied in ovarian cancer cell line OVCAR-3, and plantamajoside in all cell lines except breast adenocarcinoma MDA-MB-281 and hepatocarcinoma HepG2. The phenylethanoid glycosides showed stronger cytotoxic activity than that of the glycoside flavonoid. Acteoside and plantamajoside, at concentrations of 200 and 300 µM, respectively, had a highly toxic effect on the selected two cancer cell lines of breast adenocarcinoma MDA-MB-231 and MCF-7, ovarian cancer cell line OVCAR-3, glioblastoma cell line U138-MG, and hepatocarcinoma cell line HepG2. Both glycosides were significantly less cytotoxic towards nontumorigenic cell line MCF-12A; the effect appeared at a concentration of 400 µM. For the first time, the activity of acteoside and plantamajoside was compared in one parallel investigation. The results are discussed against a broad background of existing knowledge on biological effects, their mechanisms, and structure-activity relationships. Phenylethanoids may be potential compounds with cytotoxic activity against the selected cancer types.

Plantamajoside alleviates hypoxia-reoxygenation injury through integrin-linked kinase/c-Src/Akt and the mitochondrial apoptosis signaling pathways in H9c2 myocardial cells.

Myocardial ischemia-reperfusion injury(MIRI) is one of the common complications after myocardial infarction surgery, Oxidative stress is among the main mechanisms of myocardial ischemia-reperfusion injury. Plantamajoside (PMS), the main effective ingredient in the genus Plantain, has been reported to possess an antioxidation, anti-inflammatory and anti-apoptosis role. However, whether PMS can attenuate myocardial ischemia-reperfusion injury is not yet known. Herein, we explored the effects of PMS on hypoxia-reoxygenation (H/R) injury in H9c2 cardiomyocytes and the underling molecular mechanisms of the treatment. Network pharmacological analysis screened the top 31 key genes in the treatment of MIRI disease treated with PMS, and the result of molecular docking further illustrated the roles that the PMS play in the treatment of MIRI through its interference with integrin-linked kinase (ILK) target protein. PMS was not cytotoxic in the concentration range of 5-40 µM and increased cell survival after H/R injury in a concentration-dependent manner without affecting proliferation or growth. PMS significantly reduced the levels of lactate dehydrogenase, malonic dialdehyde, reactive oxygen species and cell apoptosis, and increased soperoxide dismutase activity compared with those of the H/R injury group. PMS promoted the protein and mRNA expression of ILK and Bcl-2, the protein expression of p-Akt, and reduced the protein and mRNA expression of Bax, Caspase-3, and Cytochrome c, the protein expression of p-c-Src. PMS has protective effects against H/R injury in H9c2 cells, and its protective mechanism may be related to reactive oxygen species clearance, activation of the ILK/c-Src/Akt pathway and inhibition of the mitochondrial apoptosis.

Metabolites analysis of plantamajoside based on gut microbiota-drug interaction.

BACKGROUND: Plantaginis Herba (Plantago asiatica L.) has the effects of clearing heat and diuresis, oozing wet and drenching. As the main active components of Plantaginis Herba (Plantago asiatica L.), plantamajoside have a wide range of antitumor activities but very low bioavailability. The process of interacting between plantamajoside and gut microbiota remains unclear. PURPOSE: To illustrate the process of interacting between plantamajoside and gut microbiota based on high-resolution mass spectrometry and targeted metabolomics methods. STUDY DESIGN AND METHODS: This experiment was divided into two parts. First, metabolites produced from plantamajoside by gut microbiota were identified and quantified based on high-resolution mass spectrometry and LC-MS/MS. Additionally, stimulation of plantamajoside on gut microbiota-derived metabolites was determined by targeted metabolomics and gas chromatography. RESULTS: We first found that plantamajoside was rapidly metabolized by gut microbiota. Then, we identified metabolites of plantamajoside by high-resolution mass spectrometry and speculated that plantamajoside was metabolized into five metabolites including calceolarioside A, dopaol glucoside, hydroxytyrosol, 3-(3-hydroxyphenyl) propionic acid (3-HPP) and caffeic acid. Among them, we quantitatively analyzed four possible metabolites based on LC‒MS/MS and found that hydroxytyrosol and 3-HPP were final products by the gut microbiota. In addition, we studied whether plantamajoside could affect the short-chain fatty acid (SCFA) and amino acid metabolites. We found that plantamajoside could inhibit the acetic acid, kynurenic acid (KYNA) and kynurenine (KN) produced by intestinal bacteria and promote the indole propionic acid (IPA) and indole formaldehyde (IALD) produced by intestinal bacteria. CONCLUSION: An interaction between plantamajoside and gut microbiota was revealed in this study. Unlike the traditional metabolic system, the special metabolic characteristics of plantamajoside in gut microbiota was found. Plantamajoside was metabolized into the following active metabolites: calceolarioside A, dopaol glucoside, hydroxytyrosol, caffeic acid and 3-HPP. Besides, plantamajoside could affect SCFA and tryptophan metabolism by gut microbiota. Especially, the exogenous metabolites hydroxytyrosol, caffeic acid and endogenous metabolites IPA may have potential association with the antitumor activity of plantamajoside.

Plantamajoside modulates immune dysregulation and hepatic lipid metabolism in rats with nonalcoholic fatty liver disease via AMPK/Nrf2 elevation.

Nonalcoholic fatty liver disease (NAFLD) is a hepatic metabolic syndrome with a rapidly increasing prevalence globally. Plantamajoside (PMS), a phenylethanoid glycoside component extracted from Plantago asiatica, has various biological properties. However, its effect on NAFLD remains unknown. The study aimed to explore the effect and mechanism of PMS on NAFLD in the high-fat diet (HFD)-feeding rats. PMS induced a decrease in body and liver weight, and the amelioration in the blood lipid parameters and pathological symptoms in HFD-feeding rats. The increase in the serum concentrations and the relative protein expressions of proinflammatory factors was decreased by the PMS treatment in HFD-induced NAFLD rats. Additionally, PMS reduced the excessive lipid vacuoles, and modified the relative expressions of proteins involved in the fatty acid synthesis and uptake in HFD-feeding rats. Mechanically, the downregulation of AMPK/Nrf2 pathway in HFD-feeding rats was restored by the PMS treatment. Inhibition of AMPK pathway reversed the PMS-induced the increase in the level of inflammatory factors, pathological symptoms, excessive lipid vacuoles, and the relative expression of proteins involved in the fatty acid synthesis and uptake. Collectively, PMS ameliorated immune dysregulation and abnormal hepatic lipid metabolism by activating AMPK/Nrf2 pathway in rats with NAFLD.

Healing effect of carboxymethyl chitosan-plantamajoside hydrogel on burn wound skin.

BACKGROUND: It is known that hydrogels based on carboxymethyl chitosan (CMCS) have properties controling microbial growth, reducing inflammatory cell infiltration, and promoting collagen deposition. Plantamajoside (PMS), a natural Chinese herbal medicine with biological activity, has the properties of reducing inflammation, anti-oxidation, and promoting wound healing. However, the effects of carboxymethyl chitosan/plantamajoside hydrogel on partial thickness burn wounds remain unclear. METHODS: The healing effect of carboxymethyl chitosan/plantamajoside hydrogel was evaluated by in vitro cell viability assay, cell migration assay, and further evaluated in a rat model of partial-thickness burn wounds. RESULTS: The hydrogels were highly porous with a pore size of about 250 µm, and these pores were interconnected. After adding plantamajoside, a dense microstructure was further formed. The hydrogels containing 0.25% plantamajoside significantly increased the viability and migration of L929 cells (P < 0.05). Carboxymethyl chitosan/plantamajoside hydrogel significantly improved wound healing, granulation tissue proliferation and re-epithelialization, and promoted collagen deposition (P < 0.05). Carboxymethyl chitosan/plantamajoside hydrogel also significantly decreased IL (interleukin)-1ß, IL-6 and TNF-α expression, and increased IL-10 expression (P < 0.05). Furthermore, carboxymethyl chitosan/plantamajoside hydrogel significantly promoted the expression levels of VEGF, CD31, α-SMA (α-smooth muscle actin) and collagen III, and reduced the expression level of collagen Ⅰ (P < 0.05). Our data suggest that carboxymethyl chitosan/plantamajoside hydrogel promotes burn wound healing by accelerating angiogenesis and collagen deposition and reducing the inflammatory response.

Plantamajoside Attenuates Neointima Formation via Upregulation of Tissue Inhibitor of Metalloproteinases in Balloon-Injured Rats.

The abnormal change of vascular smooth muscle cell (VSMC) behavior is an important cellular event leading to neointimal hyperplasia in atherosclerosis and restenosis. Plantamajoside (PMS), a phenylethanoid glycoside compound of the Plantago asiatica, has been reported to have anti-inflammatory, antioxidative, and anticancer activities. In this study, the protective effects of PMS against intimal hyperplasia and the mechanisms underlying the regulation of VSMC behavior were investigated. MTT and BrdU assays were performed to evaluate the cytotoxicity and cell proliferative activity of PMS, respectively. Rat aortic VSMC migrations after treatment with the determined concentration of PMS (50 and 150 µM) were evaluated using wound healing and Boyden chamber assays. The inhibitory effects of PMS on intimal hyperplasia were evaluated in balloon-injured (BI) rat carotid artery. PMS suppressed the proliferation in platelet-derived growth factor-BB-induced VSMC, as confirmed from the decrease in cyclin-dependent kinase (CDK)-2, CDK-4, cyclin D1, and proliferating cell nuclear antigen levels. PMS also inhibited VSMC migration, consistent with the downregulated expression and zymolytic activities of matrix metalloproteinase (MMP)2, MMP9, and MMP13. PMS specifically regulated MMP expression through p38 mitogen-activated protein kinase and focal adhesion kinase pathways. Tissue inhibitor of metalloproteinase (TIMP)1 and TIMP2 levels were upregulated via Smad1. TIMPs inhibited the conversion of pro-MMPs to active MMPs. PMS significantly inhibited neointimal formation in BI rat carotid arteries. In conclusion, PMS inhibits VSMC proliferation and migration by upregulating TIMP1 and TIMP2 expression. Therefore, PMS could be a potential therapeutic agent for vascular atherosclerosis and restenosis treatment.

Plantamajoside promotes metformin-induced apoptosis, autophagy and proliferation arrest of liver cancer cells via suppressing Akt/GSK3ß signaling.

Metformin, a well-known antidiabetic drug, exhibits anticancer effect in a variety of cancers, including liver cancer. Plantamajoside (PMS), a phenylethanoid glycoside compound isolated from Plantago asiatica, is proved to possess anticancer effects, too. In our study, we hypothesized that PMS might promote metformin mediated anticancer effects on liver cancer. The half maximal inhibitory concentration (IC50) of metformin was evaluated by cell viability assay. The influence of PMS on proliferation, migration, invasion and apoptosis of metformin-treated cells was evaluated by BrdU incorporation assay, flow cytometry, western blot, wound scratch healing assay, transwell cell migration assay and immunofluorescence. A fasting/feeding mouse model was built to evaluate the influence of PMS on metformin sensitivity in vivo. PMS (2.5, 10 or 40 µg/mL) treatment reduced the IC50 of metformin under different glucose concentrations. PMS (10 µg/mL) promoted metformin (5 mm) induced apoptosis and autophagy, and inhibition on proliferation, migration and invasion of HepG2 and HuH-7 cells. In the fasting/feeding mouse model, PMS (50 mg/kg) promoted metformin (200 mg/kg) induced proliferation arrest and apoptosis in vivo. Meanwhile, PMS reduced the level of pAkt(ser473) and GSK3ß(ser9) in HepG2 and HuH-7 cells. Restoration of Akt/GSK3ß signaling by a constitutively activated myr-Akt1 abrogated the effects of PMS on metformin-treated liver cancer cells. Our results demonstrated that PMS promoted the anticancer effects of metformin on liver cancer in vitro and in vivo.