Anti-atherogenic effects of the methanol extract of Sorbus cortex in atherogenic-diet rats

Sorbus commixta Fruit Extract Suppresses Lipopolysaccharide-Induced Neuroinflammation in BV-2 Microglia Cells via the MAPK and NF-κB Signaling Pathways

Sorbus commixta Hedl. is a traditional medicinal plant in Korea, China, and Japan with known antioxidative, anti-inflammatory, anti-atherogenic, and anti-melanin activities. However, its anti-neuroinflammatory effects remain largely unknown. In this study, we investigated the inhibitory effects of S. commixta fruit extracts on lipopolysaccharide-stimulated pro-inflammatory factors in BV-2 microglia. We compared the anti-neuroinflammatory activity of S. commixta fruit water extract (SFW) and 70% ethanol extract using a nitric oxide assay. Our data indicated that the SFW (25-100 μg/mL) treatment significantly inhibited excessive nitric oxide production in lipopolysaccharide-stimulated BV-2 microglia compared to the 70% ethanol extract. It also attenuated the expression of inducible nitric oxide synthase, cyclooxygenase-2, and pro-inflammatory cytokines such as interleukin-6 and tumor necrosis factor α. Moreover, SFW exhibited its anti-inflammatory properties by downregulating the expression of factors involved in the extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 mitogen-activated protein kinase pathways and by suppressing nuclear factor kappa B. Caffeic acid was identified as a primary component of SFW showing anti-neuroinflammatory activity. These findings suggest that SFW may offer substantial therapeutic potential for the treatment of neurodegenerative diseases involving microglia activation.

Phytochemical analysis, antioxidant and ALR2 inhibitory activity of Sorbus torminalis (L.) fruits at different maturity stages

Thirty four compounds were identified in Sorbus torminalis (L.) fruit extracts of different maturity types by means of LC-DAD-MS (ESI+) fragmentation analysis. Both immature and mature fruits were rich in flavonoid glycosides esterified with hydroxycinnamic, phenolic and dicarboxylic acids along with benzoic, phenylpropanoic and cinnamoyl quinic acid derivatives with many of them being detected for the first time in Sorbus species and in literature. Extracts and fractions were tested for their antioxidant activity (DPPH, chemiluminescence, Rancimat assays) and the estimation of the phenolic content was carried out through Folin-Ciocalteu reagent. Ethyl acetate fraction exhibited the highest scavenging activity determined as EC50 = 1.58 ± 0.22 μg/mL and EC50 = 1.64 ± 0.24 μg/mL for immature and mature fruits respectively with the DPPH test. Chemiluminescence test indicated the same fraction having the strongest antioxidant activity with an IC50 0.41 ± 0.06 μg/mL and IC50 0.50 ± 0.02 μg/mL in both maturity types. The ethyl acetate fraction of the mature fruits is considered the most potent Aldose Reductase 2 (ALR2) inhibitor with 79% demonstrating the high nutritional value of Sorbus torminalis (L.) mature fruits as a defense mechanism against the onset of diabetes mellitus secondary complications leading to the utilization of the plant for nutritional and pharmaceutical purposes.

Anti-Melanoma Activities and Phytochemical Compositions of Sorbus commixta Fruit Extracts

Sorbus commixta Hedl. (Rosaceae family) has a long history as a medicinal plant in East Asian countries. In this study, we evaluated the effect of S. commixta fruit extracts prepared with different ethanol concentrations on anti-melanoma activity, and the extraction yield of phenolic compounds and flavonoids. Using the partitioned fractions from the EtOH extract, we found that the butanol fraction (BF) possessed strong cytotoxic activity against SK-MEL-2 cells (human melanoma cells) but not against HDFa cells (human dermal fibroblast adult cells). Additionally, BF-induced cell death was mediated by the inhibition of the mitogen-activated protein kinase/extracellular regulated kinase (MEK/ERK) signaling pathway, coupled with the upregulation of caspase-3 activity in SK-MEL-2 cells. Furthermore, HPLC analysis of polyphenolic compounds suggested that S. commixta fruits contained several active compounds including chlorogenic acid, rutin, protocatechuic acid, and hydroxybenzoic acid, all of which are known to possess anti-cancer activities. Although this study has been carried out by cell-based approach, these results suggest that S. commixta fruits contain promising anti-melanoma compounds.

Sorbus commixta water extract induces apoptotic cell death via a ROS-dependent pathway

The stembark of Sorbus commixta Hedl. has been used for treating asthma, bronchitis, gastritis and edema. However, the anticancer and proapoptotic effects of the water extract of the stembark of S. commixta (SCE) remain unknown. In the present study, it was shown that SCE inhibited the cell viability of the hepatocellular carcinoma cell lines Hep3B and HepG2, and of the colon carcinoma cell line HCT116. DNA content analysis indicated that SCE increased the sub-G1 population of HCT116 cells. In addition, degradation of nuclear DNA and levels of proapoptotic cascade components, including caspase-9, caspase-3 and poly ADP-ribose polymerase, were augmented by SCE treatment. Mitochondrial membrane potential and the ratio of B-cell lymphoma-2 (Bcl-2)/Bcl-2-associated X protein (Bax) were also reduced. Furthermore, SCE increased the expression of proapoptotic proteins, including p21, p27 and p53. Mouse double minute 2 homology, a negative regulator of p53, was cleaved by SCE treatment. Intracellular reactive oxygen species (ROS) production was also increased by SCE treatment. However, the SCE-induced cytotoxic effects and the increased expression of proapoptotic proteins, including p53 and p21, and reduced Bcl-2/Bax ratio, could be attenuated by N-acetyl cysteine, an ROS inhibitor. Taken together, these results indicate that SCE is a potent proapoptotic herbal medicine, which exerts its effects via the ROS-mediated mitochondrial pathway.

Calpain inhibitor I attenuates atherosclerosis and inflammation in atherosclerotic rats through eNOS/NO/NF-κB pathway

We previously reported that calpain, the Ca2+-sensitive cysteine protease, gets involved in atherogenesis. This study aimed to investigate the effects of calpain inhibitor I (CAI, 5 mg/kg per day) with or without NG-nitro-l-arginine-methyl ester (l-NAME) (100 mg/kg per day), the inhibitor of nitric oxide synthase (NOS), on atherosclerosis and inflammation in a rat model induced by high-cholesterol diet (HCD). The results demonstrated HCD increased protein expression of calpain-1 but not calpain-2 in aortic tissue. In addition, CAI reduced the thickness of atherosclerotic intima compared with HCD group, which was weakened by the l-NAME combination. CAI with or without l-NAME decreased the activity of calpain in the aorta. Also, CAI decreased the expressions of vascular cell adhesion molecule-1 (VCAM-1), intracellular cell adhesion molecule-1 (ICAM-1), and monocyte chemoattractant protein-1 (MCP-1) in the aorta at the levels of both mRNA and protein. Furthermore, CAI increased the activity and the protein expression of endothelial NOS (eNOS) accompanied by increased content of NO and downregulated the protein expression of nuclear factor κB (NF-κB) of the nucleus in the aorta. However, the abovementioned effects were at least partly cancelled by l-NAME except for the protein expression of eNOS. The results suggested that CAI attenuated atherosclerosis and inflammation through eNOS/NO/NF-κB pathway.

In Vitro Antiviral Activity of Sakuranetin against Human Rhinovirus 3

Objectives

Rhinoviruses (RVs) cause common cold and are associated with exacerbation of chronic inflammatory respiratory diseases. Until now, no clinically effective antiviral chemotherapeutic agents to treat diseases caused by human rhinoviruses (HRVs) have been reported. We assessed the anti-HRV3 activity of sakuranetin isolated from Sorbus commixta Hedl. in human epithelioid carcinoma cervix (HeLa) cells, to evaluate its anti-rhinoviral potential in the clinical setting.

Methods

Antiviral activity and cytotoxicity as well as the effect of sakuranetin on HRV3-induced cytopathic effects (CPEs) were evaluated using the sulforhodamine B (SRB) method using CPE reduction. The morphology of HRV3-infected cells was studied using a light microscope.

Results

Sakuranetin actively inhibited HRV3 replication and exhibited antiviral activity of more than 67% without cytotoxicity in HeLa cells, at 100 μg/mL. Ribavirin showed anti-HRV3 activity similar to that of sakuranetin. Treatment of HRV-infected HeLa cells with sakuranetin visibly reduced CPEs.

Conclusion

The inhibition of HRV production by sakuranetin is mainly due to its general antioxidant activity through inhibition of viral adsorption. Therefore, the antiviral activity of sakuranetin should be further investigated to elucidate its mode of action and prevent HRV3-mediated diseases in pathological conditions.

Effect of Sorbus commixta on the invasion and migration of human hepatocellular carcinoma Hep3B cells

Tumor metastasis is a main cause of cancer-related morbidity and mortality. Thus, a number of medicinal herbs and phytochemicals have been investigated as possible candidates for the inhibition of cancer metastasis. Sorbus commixta Hedl. (SC) is a traditional medicinal plant used in the treatment of inflammatory diseases, as it has antioxidant, anti-inflammatory, anti-atherosclerotic and anti-hepatotoxic activities. In this study, we demonstrate that the water extract of SC exerts inhibitory effect on the invasion and migration of hepatocellular carcinoma Hep3B cells. The activity and expression of matrix metalloproteinase (MMP)-9, which is responsible for the invasion of cancer cells, was decreased by SC treatment. The invasive and migratory potentials of the Hep3B cells were also decreased, as evidence by in vitro assay using the Boyden chamber system. In addition, the expression of the chemokine receptors, C-X-C chemokine receptor type 4 (CXCR)4 and C-X-C chemokine receptor type 6 (CXCR6), were inhibited by SC in Hep3B cells. Furthermore, actin fiber organization was markedly suppressed by SC treatment. Taken together, the findings of this study suggest for the first time, to the best of our knowledge, that SC suppresses the invasion and migration of highly metastatic Hep3B cells.

Anti-Hypertensive Herbs and Their Mechanisms of Action: Part II

Traditional medicine has a history extending back to thousands of years, and during the intervening time, man has identified the healing properties of a very broad range of plants. Globally, the use of herbal therapies to treat and manage cardiovascular disease (CVD) is on the rise. This is the second part of our comprehensive review where we discuss the mechanisms of plants and herbs used for the treatment and management of high blood pressure. Similar to the first part, PubMed and ScienceDirect databases were utilized, and the following keywords and phrases were used as inclusion criteria: hypertension, high blood pressure, herbal medicine, complementary and alternative medicine, endothelial cells, nitric oxide (NO), vascular smooth muscle cell (VSMC) proliferation, hydrogen sulfide, nuclear factor kappa-B (NF-κB), oxidative stress, and epigenetics/epigenomics. Each of the aforementioned keywords was co-joined with plant or herb in question, and where possible with its constituent molecule(s). This part deals in particular with plants that are used, albeit less frequently, for the treatment and management of hypertension. We then discuss the interplay between herbs/prescription drugs and herbs/epigenetics in the context of this disease. The review then concludes with a recommendation for more rigorous, well-developed clinical trials to concretely determine the beneficial impact of herbs and plants on hypertension and a disease-free living.

In Vivo Screening of Traditional Medicinal Plants for Neuroprotective Activity against Aβ42 Cytotoxicity by Using Drosophila Models of Alzheimer's Disease

Alzheimer's disease (AD) is the most common neurodegenerative disorder, characterized by progressive neuronal loss with amyloid β-peptide (Aβ) plaques. Despite several drugs currently used to treat AD, their beneficial effects on AD progress remains under debate. Here, we established a rapid in vivo screening system using Drosophila AD models to assess the neuroprotective activities of medicinal plants that have been used in traditional Chinese medicine. Among 23 medicinal plants tested, the extracts from five plants, Coriandrum sativum, Nardostachys jatamansi, Polygonum multiflorum (P. multiflorum), Rehmannia glutinosa, and Sorbus commixta (S. commixta), showed protective effects against the Aβ42 neurotoxicity. We further characterized the neuroprotective activity of ethanol extracts from P. multiflorum and S. commixta. Aβ42-expressing flies that we used showed AD neurological phenotypes, such as decreased survival and motility and increased cell death and reactive oxygen species level. However, feeding these flies extracts from P. multiflorum or S. commixta showed strong suppression of such phenotypes. Similar results were observed in human cells, so that the treatment of P. multiflorum and S. commixta extracts increased the viability of Aβ-treated SH-SY5Y cells. Moreover, 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside, one of the main constituents of P. multiflorum, also showed similar protective activity against Aβ42 cytotoxicity in both Drosophila and human cells. Taken together, our results suggest that both P. multiflorum and S. commixta have therapeutic potential for the treatment of neurodegenerative diseases, such as AD.

β-sitosteryl-3-O-β-glucopyranoside isolated from the bark of Sorbus commixta ameliorates pro-inflammatory mediators in RAW 264.7 macrophages

The bark of Sorbus commixta has been used in Asian traditional medicine for treatment of cough, asthma, bronchial disorders, gastritis and dropsy. However, the anti-inflammatory effect of β-sitosteryl-3-O-β-glucopyranoside, a major compound of the bark of S. commixta, is poorly understood. In this study, we investigated the anti-inflammatory effect and the underlying molecular mechanisms of β-sitosteryl-3-O-β-glucopyranoside in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Prostaglandin E₂ (PGE₂) and cytokines released from cells were measured using EIA assay kit. The expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, Tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) was measured by real-time polymerase chain reaction (RT-PCR) and/or Western blot analysis. β-sitosteryl-3-O-β-glucopyranoside inhibited the production of nitric oxide (NO) and PGE₂ along with the expression of iNOS and COX-2 in LPS-stimulated RAW264.7 cells. In addition, β-sitosteryl-3-O-β-glucopyranoside reduced the release of pro-inflammatory cytokines, such as TNF-α, IL-1β and IL-6. Moreover, β-sitosteryl-3-O-β-glucopyranoside inhibited the NF-κB activation induced by LPS, which was associated with the abrogation of IκBα degradation and subsequent decreases in nuclear p65 levels. The result suggested that the β-sitosteryl-3-O-β-glucopyranoside inhibited NO and pro-inflammatory productions by down-regulating the gene expression of pro-inflammatory mediators via the negative regulation of the NF-кB pathway in LPS-stimulated RAW 264.7 cells.

Variation in the Contents of Neochlorogenic Acid, Chlorogenic Acid and Three Quercetin Glycosides in Leaves and Fruits of Rowan (Sorbus) Species and Varieties from Collections in Lithuania

Our research aim was to investigate the quantitative composition of neochlorogenic acid, chlorogenic acid, rutin, hyperoside and isoquercitrin in leaves and fruit of introduced rowan plants to Lithuania using a HPLC method. In leaf and fruit samples, quantitative estimation of neochlorogenic acid (in leaf samples 1.11–11.49 mg/g, in fruit samples 0.93–5.43 mg/g), chlorogenic acid (in leaf samples 2.74–21.91 mg/g, in fruit samples 0.55–7.50 mg/g), rutin (in leaf samples 0.03–4.88 mg/g, in fruit samples 0.02-0.39 mg/g), hyperoside (in leaf samples 0.15–7.44 mg/g, in fruit samples 0.02–1.19 mg/g) and isoquercitrin (in leaf samples 0.75–5.24 mg/g, in fruit samples 0.02-0.65 mg/g) was performed. In leaf samples, the total content of identified phenolic compounds ranged from 7.18 to 35.74 mg/g. In fruit, raw material total content of neochlorogenic acid, chlorogenic acid and identified flavonoids varied from 2.24 to 11.19 mg/g. Comparison of raw material samples of Sorbus species according to their quantitative composition of identified phenolic compounds using cluster analysis singularized S. commixta leaf and fruit samples. These contained the highest contents of chlorogenic acid, hyperoside and isoquercitrin, but also the lowest contents of neochlorogenic acid and rutin. The highest contents of neochlorogenic acid were recorded for S. lancifolia leaves, and of rutin for S. anglica leaves.

Anti-inflammatory activity of Sorbus commixta water extract and its molecular inhibitory mechanism

ETHNOPHARMACOLOGICAL SIGNIFICANCE

Sorbus commixta Hedl. (Rosaceae) is a well known traditionally valuable medicinal plant in Korea, China and Japan. This plant has been prescribed for long time for various inflammatory symptoms such as asthma, bronchitis, gastritis and dropsy.

AIM OF STUDY

Although a number of pharmacological properties have already been demonstrated, the anti-inflammatory effect of this plant and its associated molecular mechanisms has not yet been fully investigated.

MATERIALS AND METHODS

In order to address the anti-inflammatory activity of S. commixta water extract (Sc-WE), lipopolysaccharide (LPS)-stimulated macrophages were employed and production of inflammatory mediators by these cells were evaluated.

RESULTS

Sc-WE significantly suppressed the production of nitric oxide (NO) and prostaglandin (PG)E(2) in a dose-dependent manner and blocked ear edema formation induced by arachidonic acid in mouse. In addition, this extract effectively diminished the mRNA levels of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, indicating that the inhibition occurs at the transcriptional level. Interestingly, Sc-WE remarkably blocked NF-κB translocation and its upstream signaling events by inhibition of κBα (IκBα), IκBα kinase (IKK), Akt (protein kinase B), phosphoinositide-dependent kinase 1 (PDK1), p85/phosphoinositide-3-kinase (PI3K), as per the results obtained from the reporter gene assay and immunoblotting analysis. More intriguingly, Sc-WE suppressed activities of Src and Syk kinases as well as their phosphorylation levels without altering molecular complex formation between them and toll like receptor (TLR)4 or MyD88, an adaptor protein of TLR4-mediated signaling.

CONCLUSION

Therefore, our results suggest that Sc-WE can be developed as a potent anti-inflammatory remedy, acting by suppressing the inflammatory signaling cascade composed of Src, Syk, and NF-κB.

Assessment of the content of phenolics and antioxidant action of inflorescences and leaves of selected species from the genus Sorbus sensu stricto

In order to find new sources of natural antioxidants, the antioxidant potential of 70% methanolic extracts from the inflorescences and leaves of 16 species from the genus Sorbus s.s. was evaluated using two complementary invitro test systems: the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-scavenging assay and the AAPH [2,2′-azobis-(2-amidinopropane)dihydrochloride]-induced linoleic acid (LA) peroxidation test. The radical-scavenging capacities of the extracts towards the DPPH radical were in the range of 0.25−0.86 millimolar Trolox^® equivalents/g dry weight. They were significantly correlated (r = -0.8089, p < 0.001) with the results of the LA-peroxidation test, indicating the Sorbus extracts to be universal antioxidants. Significant linear correlations were also found between the different antioxidant potentials and total phenolic contents as estimated by the Folin-Ciocalteu method and further verified by serial determinations of proanthocyanidins, chlorogenic acid isomers and flavonoids (|r| in the range of 0.71−0.95, p < 0.001). Cluster analysis of the data matrix identified the ten samples (inflorescences of S. aucuparia, S. pohuashanensis, S. decora, S. koehneana, S. commixta, S. gracilis, and S. sitchensis, and the leaves of S. wilfordii, S. pogonopetala, and S. gracilis) exhibiting the highest antioxidant activity and total phenolic levels and therefore the greatest potential as effective sources for natural health products.

Inhibition of protein tyrosine phosphatase 1B by lupeol and lupenone isolated from Sorbus commixta

Protein tyrosine phosphatase 1B (PTP1B) appears to be an attractive target for the development of new drugs for type 2 diabetes and obesity. In our preliminary test, a MeOH extract of the stem barks of Sorbus commixta Hedl. (Rosaceae) showed strong PTP1B inhibitory activity. Bioassay-guided fractionation of the MeOH extract resulted in the isolation of two lupane-type triterpenes, lupenone (1) and lupeol (2). Compounds 1 and 2 inhibited PTP1B with IC(50) values of 13.7 +/- 2.1 and 5.6 +/- 0.9 microM, respectively. Kinetic studies revealed that both the compounds 1 and 2 are non-competitive inhibitors of PTP1B that decrease V(max) values with no effect on K(m) values.

Effect of traditional Chinese herbal Bu-Wang-San on synaptic plasticity in ovariectomised rats

Objectives

The neuroprotective effects of Bu-Wang-San (BWS) and its effects on spine synapse plasticity were investigated in ovariectomised rats.

Methods

Thirty-six ovariectomised rats were divided into three groups: untreated controls, treatment with 17β-estradiol or with BWS. After 3 months, spatial acquisition and spatial retention were measured using the Morris water maze. Swim time, swim distance, swim speed, quadrant time and platform crossing were recorded. Spine synapse density in the hippocampus was examined by transmission electron microscopy. The expression of synaptophysin P38 (P38) mRNA was examined by real-time PCR and the protein expression of P38 was examined by Western blot.

Key findings

In spatial acquisition and spatial retention, the BWS group functioned significantly better than the control group. Ultrastructural observation of the hippocampus showed that BWS significantly increased spine synapse density compared with the ovariectomised group. In addition, BWS significantly increased P38 mRNA and protein expression in the hippocampus. Thus, the positive effect of BWS on learning and memory in rats was associated with increased spinal synapse density and increased P38 mRNA and protein expression in the hippocampus following menopause-induced injury.

Conclusions

These results suggest that BWS could improve cognitive ability following menopause-induced impairment of learning and memory.

A chalcone glycoside from the fruits of Sorbus commixta Hedl

Sorbus commixta Hedl. (Rosaceae) has been traditionally used in oriental countries for the treatment of asthma and other bronchial disorders. In this study, a chalcone glycoside was isolated from the ethyl acetate extract of the fruits of this plant. The compound was identified as neosakuranin based on the spectroscopic analysis and comparion with literature data. This is the first report of isolation of neosakuranin from Sorbus commixta.

Inhibitory effect of Ginkgo biloba extract on hyperhomocysteinemia-induced intimal thickening in rabbit abdominal aorta after balloon injury

Ginkgo biloba extract (GBE) has been widely used to treat cardiovascular and cerebrovascular disorders. Hyperhomocysteinemia (Hhcy) is associated with the risk of atherosclerosis and restenosis after angioplasty. The objective of this study was to investigate whether GBE could attenuate the Hhcy-induced intimal thickening after balloon injury in rabbit abdominal aorta. It was observed in this study that GBE could decrease the neointima area (NA) and the ratio of the neointima area to the media area (NA/MA), down-regulate the mRNA expression of matrix metalloproteinase-9 (MMP-9) and up-regulate the protein expression of p21 (WAF1/CIP1) (p21). It suggests that GBE can reverse the Hhcy-induced neointima formation in rabbits following balloon injury, and the suppressive effect of GBE on the migration and proliferation of vascular smooth muscle cells (VSMCs) may contribute to its actions.

The pharmacological potential of Sorbus commixta cortex on blood alcohol concentration and hepatic lipid peroxidation in acute alcohol-treated rats

The effect of Sorbus commixta cortex, a traditional herbal medicine used for the treatment of bronchitis, gastritis and dropsy, on blood alcohol concentration (BAC) and hepatic lipid peroxidation was examined in acute alcohol-treated rats. A 30-min pretreatment with a methanol extract of S. commixta cortex (SC) at concentrations higher than 200 mg kg(-1) resulted in a significant decrease in BAC and the ethyl acetate fraction (SE) of the extract showed the highest potency, with a maximum of a 46% decrease at 150 mg kg(-1) 2 h after alcohol administration (3.0 g kg(-1)) compared with the control group (P < 0.005). The rapid reduction in BAC did not appear to be due to the protection or activation of hepatic alcohol dehydrogenase (ADH) activity by SE. Hepatic malondialdehyde (MDA) levels were significantly increased by acute alcohol administration within 6 h, although pretreatment with the SE caused a significant decrease in MDA levels compared with alcohol treatment alone. Hepatic glutathione (GSH) levels and superoxide dismutase (SOD) activity remained unchanged by alcohol, SE alone or by the combined treatment of alcohol and SE. However, catalase activity was significantly reduced by acute alcohol administration and pretreatment with the SE led to significant protection of its activity. These results suggest that pretreatment with SE reduces hepatic lipid peroxidation by decreasing the bioavailability of alcohol and its oxidative metabolites, such as H2O2, at least partly, through the protection of hepatic catalase in acute alcohol-treated rats.