Methanol extract of Sorbus commixta cortex prevents vascular inflammation in rats with a high fructose-induced metabolic syndrome

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.

Suppression of Ultraviolet B-mediated Matrix Metalloproteinase Generation by Sorbus commixta Twig Extract in Human Dermal Fibroblasts

Sorbus commixta is a traditional oriental medicinal plant that grows in East Asian countries such as Korea, Japan and China. The twig of S. commixta has been considered valuable for centuries to treat diseases including asthma, cough and other bronchial disorders. However, the effect of S. commixta twig extract on human skin has not been investigated well. The present study aimed at assessing the antiphotoaging effect of S. commixta twig ethanol extract (STE) on ultraviolet B (UVB)-induced matrix metalloproteinase (MMP) levels and its underlying mechanism in human dermal fibroblasts. In this study, we found that STE (12.5-50 μg mL^-1 ) treatment significantly inhibited UVB-induced MMP-1, MMP-2 and MMP-3 expression, concomitant with a downregulation of intracellular ROS generation. These effects might be associated with a STE-induced inhibition of the mitogen-activated protein kinase (MAPK) pathway. Furthermore, STE also downregulated UVB-induced c-Fos expression in a concentration-dependent manner, but had no inhibitory effect on c-Jun phosphorylation. Taken together, these results indicate that STE may be an antiphotoaging agent and that its effect may occur via its inhibition of MMPs expression and MAPK pathway activation.

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.

Lupeol Isolated from Sorbus commixta Suppresses 1α,25-(OH)2D3-Mediated Osteoclast Differentiation and Bone Loss in Vitro and in Vivo

Lupeol is a lupane-type triterpene isolated from Sorbus commixta, an oriental medicine used to treat arthritis and inflammatory diseases. However, the antiosteoporotic effects of S. commixta or any of its constituents have not been studied yet. In the present study, we have examined the effect of lupeol (a major active triterpenoid isolated from S. commixta) on osteoclastogenesis and sought to elucidate its underlying molecular mechanisms. We evaluated whether lupeol antagonized osteoclast differentiation and bone resorption. Lupeol markedly inhibited osteoclast differentiation and bone resorption activity through its effects on MAP kinases and transcription factors (NF-κB, NFATc1, and c-Fos) downstream of the osteoclast differentiation factor receptor RANK. Furthermore, in vivo efficacy of lupeol was confirmed by using an animal model of hypercalcemic mediated bone loss. Taken together, lupeol showed strong inhibitory effects on osteoclastogenesis. Supplementation with S. commixta and lupeol could be beneficial for bone health or osteoclast-related diseases such as osteoporosis, Paget's disease, osteolysis associated with periodontal disease, and multiple myeloma.

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.

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.

The protective effect of Yi-Qi-Yang-Yin-Ye, a compound of traditional Chinese herbal medicine in diet-induced obese rats

The present study was undertaken to determine the effect of Yi-Qi-Yang-Yin-Ye (Y-Q-Y-Y-Y), a compound of Traditional Chinese Herbal Medicine, on insulin resistance (IR) in the diet-induced obese rat model induced by intravenous injection with a low dose of streptozotocin and fed a high fat and high caloric diet. Y-Q-Y-Y-Y (2, 4, 8 g/kg) was administered via gavage daily for 4 weeks. The results showed that Y-Q-Y-Y-Y treatment decreased the levels of body weight, total cholesterol (TC), triglycerides (TG), low density lipoprotein-cholesterol (LDL-C), free fatty acid (FFA), insulin (INS) and fast blood glucose (FBG) and increased the level of high density lipoprotein-cholesterol (HDL-C) in the diet-induced obese rats. Glucose tolerance was improved in the diet-induced obese rats treated with Y-Q-Y-Y-Y as well as GIR (glucose infusion rate) in the hyperinsulinemic euglycemic clamp experiment compared to the model control rats (p < 0.01). Moreover, treatment with Y-Q-Y-Y-Y up-regulated glycogen contents in both liver and skeletal muscle and increased insulin receptor amounts on the erythrocytes surface as assessed by using (125)I-labeled auto-antibodies against insulin receptors. Taken together, our data suggested that Yi-Qi-Yang-Yin-Ye ameliorates insulin resistance in the diet-induced obese rats.

Preparation of botanical samples for biomedical research

Plants are chemical storehouses, a fact which has driven countless multidisciplinary quests for bioactive compounds. As the very first step of botanical research, the whole desire is to find "hit" plants with specific bioactivities. It is logical to use some strategies that can maximize the chances of finding these "hits" with limited time and resources. In addition to selecting the right plants for screening, how the plant extracts are prepared can also influence the bioactivity screening outcomes. An extract from the same plant material can be quite different in chemical composition having different preparations. Because of the complex mixture nature of plant extracts, it is possible artifact activities may be observed. Thus confirmatory activity tests are often necessary to warrant the next laborious isolation step. A bioassay directed isolation approach may be the most efficient in identifying the bioactive compounds because of the narrowed focus at each isolation step, but a phytochemistry isolation approach is appropriate to characterize a purified bioactive extract. In fact, these two approaches can be taken intermittently whenever efficiency can be improved. Finally, use of the identified active compounds is now broader. In addition to determining a lead compound to continue a drug development path, there is an increasing interest in support for the use of botanical extracts as botanical drugs. Instead of dropping the extract after extracting the lead compound, the natural analogues representing the purified extract now have a chance to become leading compounds in the pursuit of novel therapies for metabolic syndrome and other diseases.

Dietary fructose and the metabolic syndrome

PURPOSE OF REVIEW

Fructose, a naturally found sugar in many fruits, is now commonly used as an industrial sweetener and is excessively consumed in Western diets. High fructose intake is increasingly recognized as causative in development of prediabetes and metabolic syndrome. The mechanisms underlying fructose-induced metabolic disturbances are unclear but are beginning to be unravelled. This review presents recent findings in this field and an overall mechanistic insight into the metabolic effects of dietary fructose and its role in metabolic syndrome.

RECENT FINDINGS

Recent animal studies have confirmed the link between fructose feeding and increased plasma uric acid, a potentially causative factor in metabolic syndrome. Advanced glycation end products are also implicated because of their direct protein modifications and indirect effects on inflammation and oxidative stress. Human studies have demonstrated fructose's ability to change metabolic hormonal response, possibly contributing to decreased satiety.

SUMMARY

There is much evidence from both animal models and human studies supporting the notion that fructose is a highly lipogenic nutrient that, when consumed in high quantities, contributes to tissue insulin insensitivity, metabolic defects, and the development of a prediabetic state. Recently evidence has helped to decipher the mechanisms involved in these metabolic changes.