Scutellarin, a flavonoid compound from Scutellaria barbata, suppresses growth of breast cancer stem cells in vitro and in tumor-bearing mice

BACKGROUND

Scutellaria barbata D. Don (SB), commonly known as Ban Zhi Lian and firstly documented by Shigong Chen, is a dried whole plant that has been studied for its therapeutic effects on breast cancer, colon cancer, and prostate cancer. Among its various compounds, scutellarin (SCU) has been demonstrated with anti-tumor effects.

PURPOSE

This study aimed to evaluate the effects of SB water extract (SBW) and scutellarin on breast cancer stem cells (BCSCs), and to investigate their potential therapeutic effects on breast tumors in mice.

METHODS

BCSCs were enriched from human breast cancer cells (MDA-MB-231 and MDA-MB-361) and their characteristics were analyzed. The effects of varying concentrations of SBW and scutellarin on cell viability, proliferation, self-renewal, and migration abilities were studied, along with the underlying mechanisms. The in vivo anti-tumor effects of scutellarin were further evaluated in SCID/NOD mice. Firstly, mice were inoculated with naïve BCSCs and subjected to treatment with scutellarin or vehicle. Secondly, BCSCs were pre-treated with scutellarin or vehicle prior to inoculation into mice.

RESULTS

The derived BCSCs expressed CD44, CD133 and ALDH1, but not CD24, indicating that BCSCs have been successfully induced from both MDA-MB-231 and MDA-MB-361 cells. Both SBW and scutellarin reduced the viability, proliferation, sphere and colony formation, and migration of BCSCs. In mice with tumors derived from naïve BCSCs, scutellarin significantly reduced tumor growth, expression of proliferative (Ki67) and stem cell markers (CD44), and lung metastasis. In addition, pre-treatment with scutellarin also slowed tumor growth. Western blot results suggested the involvement of Wnt/β-catenin, NF-κB, and PTEN/Akt/mTOR signaling pathways underlying the inhibitory effects of scutellarin.

CONCLUSION

Our study demonstrated for the first time that both SB water extract and scutellarin could reduce the proliferation and migration of BCSCs in vitro. Scutellarin was shown to possess novel inhibitory activities in BCSCs progression. These findings suggest that Scutellaria barbata water extract, in particular, scutellarin, may have potential to be further developed as an adjuvant therapy for reducing breast cancer recurrence.

Xylooligosaccharides from corn cobs alleviate loperamide-induced constipation in mice via modulation of gut microbiota and SCFA metabolism

This study aimed to optimize the structure and efficacy of xylooligosaccharides (XOSs) from corn cobs in constipated mice. Structural analysis revealed that XOSs from corn cobs were composed of β-Xyl-(1 →4)-[β-Xyl-(1→4)]n-α/β-Xyl (n = 0-5) without any other substituents. XOS administration significantly reduced the defecation time, increased the gastrointestinal transit rate, restored the gastrointestinal neurotransmitter imbalance, protected against oxidative stress, and reversed constipation-induced colonic inflammation. Fecal metabolite and microbiota analysis showed that XOS supplementation significantly increased short chain fatty acid (SCFA) levels and improved the gut microbial environment. These findings highlighted the potential of XOSs from corn cobs as an active ingredient for functional foods or as a therapeutic agent in constipation therapy.

Scutellarin acts on the AR-NOX axis to remediate oxidative stress injury in a mouse model of cerebral ischemia/reperfusion injury

BACKGROUND

Oxidative stress plays an important role in the pathology of ischemic stroke. Studies have confirmedthat scutellarin has antioxidant effects against ischemic injury, and we also reported that the involvement of Aldose reductase (AR) in oxidative stress and cerebral ischemic injury, in this study we furtherly explicit whether the antioxidant effect of scutellarin on cerebral ischemia injury is related to AR gene regulation and its specific mechanism.

METHODS

C57BL/6N mice (Wild-type, WT) and AR knockout (AR^-/-) mice suffered from transient middle cerebral artery occlusion (tMCAO) injury (1 h occlusion followed by 3 days reperfusion), and scutellarin was administered from 2 h before surgery to 3 days after surgery. Subsequently, neurological function was assessed by the modified Longa score method, the histopathological morphology observed with 2,3,5-triphenyltetrazolium chloride (TTC) and hematoxylin-eosin (HE) staining. Enzyme-linked immunosorbent assay (Elisa) was used to detect the levels of ROS, 4-hydroxynonenal (4-HNE), 8-hydroxydeoxyguanosine (8-OHDG), Neurotrophin-3 (NT-3), poly ADP-ribose polymerase-1 (PARP1) and 3-nitrotyrosine (3-NT) in the ischemic penumbra regions. Quantitative proteomics profiling using quantitative nano-HPLC-MS/MS were performed to compare the protein expression difference between AR^-/- and WT mice with or without tMCAO injury. The expression of AR, nicotinamide adenine dinucleotide phosphate oxidases (NOX1, NOX2 and NOX4) in the ipsilateral side of ischemic brain were detected by qRT-PCR, Western blot and immunofluorescence co-staining with NeuN.

RESULTS

Scutellarin treatment alleviated brain damage in tMCAO stroke model such as improved neurological function deficit, brain infarct area and neuronal injury and reduced the expression of oxidation-related products, moreover, also down-regulated tMCAO induced AR mRNA and protein expression. In addition, the therapeutic effect of scutellarin on the reduction of cerebral infarction area and neurological function deficits abolished in AR^-/- mice under ischemia cerebral injury, which indicated that the effect of scutellarin treatment on tMCAO injury is through regulating AR gene. Proteomic analysis of AR^-/- and WT mice indicated AR knockout would affect oxidation reaction even as NADPH related process and activity in mice under cerebral ischemia conditions. Moreover, NOX isoforms (NOX1, NOX2 and NOX4) mRNA and protein expression were significant decreased in neurons of penumbra region in AR^-/- mice compared with that in WT mice at 3d after tMCAO injury, which indicated that AR should be the upstream protein regulating NOX after cerebral ischemia.

CONCLUSIONS

We first reported that AR directly regulates NOX subtypes (not only NOX2 but also NOX1 and NOX4) after cerebral ischaemic injury. Scutellarin specifically targets the AR-NOX axis and has antioxidant effects in mice with cerebral ischaemic injury, providing a theoretical basis and accurate molecular targets for the clinical application of scutellarin.

Paludibacter propionicigenes GH10 xylanase as a tool for enzymatic xylooligosaccharides production from heteroxylans

Bioconversion of lignocellulosic biomass into value-added products relies on polysaccharides depolymerization by carbohydrate active enzymes. This work reports biochemical characterization of Paludibacter propionicigenes xylanase from GH10 (PpXyn10A) and its application for enzymatic xylooligosaccharides (XOS) production from commercial heteroxylans and liquor of hydrothermally pretreated corn cobs (PCC). PpXyn10A is tolerant to ethanol and NaCl, and releases xylobiose (X2) and xylotriose (X3) as the main hydrolytic products. The conversion rate of complex substrates into short XOS was approximately 30% for glucuronoxylan and 8.8% for rye arabinoxylan, after only 4 h; while for PCC, PpXyn10A greatly increased unbranched XOS yields. B. adolescentis fermentation with XOS from beechwood glucuronoxylan produced mainly acetic and lactic acids. Structural analysis shows that while the glycone region of PpXyn10A active site is well preserved, the aglycone region has aromatic interactions in the +2 subsite that may explain why PpXyn10A does not release xylose.

Sulphated glucuronomannan tetramer and hexamer from Sargassum thunbergii exhibit anti-human cytomegalovirus activity by blocking viral entry

Human cytomegalovirus (HCMV) remains a major public health burden worldwide. The anti-HCMV activity of glucuronomannan oligosaccharides (Gs) and sulphated glucuronomannan oligosaccharides (SGs) was investigated. Among these Gs and SGs, G4S1 and G6S1 (higher sulphated glucuronomannan tetramer and hexamer) showed satisfactory anti-HCMV activity starting at 50 μg/mL and 10 μg/mL, respectively. The results of the morphology, western blotting, qPCR and TCID50 assay showed that they prevented lytic cytopathic changes, inhibited the expression of IE1/2 and UL44, and reduced the UL123 copy number and virus titre significantly. It was interesting to note that degree of sulphation and polymerization was more important for anti-HCMV activity. Moreover, the anti-HCMV activities of G4S1 and G6S1 were stable when stored at 4 °C, -20 °C, and -80 °C for at least three months and mainly occurred in the early stage of HCMV infection through the negative charge of the sulphate groups and the interaction between SGs and the host cells.

Metanil yellow promotes oxidative stress, astrogliosis, and apoptosis in the cerebellar cortex of adult male rat with possible protective effect of scutellarin: A histological and immunohistochemical study

Metanil yellow is a food dye that has harmful impacts on different body systems. Scutellarin has antioxidant, antiapoptotic, and anti-inflammatory activities. The aim of the current research was to study the effect of chronic administration of metanil yellow on the cerebellar cortex of rats and to evaluate the protective effect of scutellarin. Forty adult male rats were allocated into four groups: group I acted as control, group II was administrated scutellarin (100 mg/kg/day), group III was administrated metanil yellow (200 mg/kg/day), and group IV was administrated scutellarin and metanil yellow as in group II and group III. The agents were administered via oral gavage for 8 weeks. Metanil yellow induced a significant rise in the malondialdehyde coupled with a significant reduction in the superoxide dismutase and glutathione peroxidase. The Purkinje cells were irregular and shrunken with condensed nuclei. A significant elevation in glial fibrillary acidic protein (GFAP) and cleaved caspase-3 as well as a significant reduction of synaptophysin expression were revealed in comparison with the control group. Interestingly, few changes were noticed in rats given metanil yellow concomitant with scutellarin. In conclusion, scutellarin could protect against metanil yellow-induced alterations in the cerebellar cortex by reducing oxidative stress and minimizing gliosis.

Protective mechanism of Erigeron breviscapus injection on blood-brain barrier injury induced by cerebral ischemia in rats

This study investigates the protective effect of Erigeron breviscapus injection, a classic traditional Chinese medicine most typically used by Chinese minority to treat stroke, on cerebral ischemia-reperfusion injury and the related signaling pathways. Use network pharmacology methods to study the relationship between E. breviscapus (Vant.) Hand-Mazz. and ischemic stroke, predict the mechanism and active ingredients of E. breviscapus (Vant.) Hand-Mazz. in improving ischemic stroke disease. We study the protective effect of E. breviscapus injection on blood-brain barrier (BBB) injuries induced by cerebral ischemia in rats by regulating the ROS/RNS-MMPs-TJs signaling pathway. The rat model of focal cerebral ischemia-reperfusion injury has been prepared using the wire-suppository method. Firstly, the efficacy of E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid in protecting BBB injury caused by cerebral ischemia has been evaluated. Secondly, the following two methods have been used to study the mechanism of E. breviscapus injection in regulating the ROS/RNS-MMPS-TJS signaling pathway: real-time PCR and western blot for the determination of iNOS, MMP-9, claudin-5, occludin, ZO-1 mRNA and protein expression in brain tissue. We find that PI3K-Akt signaling pathway predicted by network pharmaology affects the blood-brain barrier function, so we chose the blood-brain barrier-related MMP-9, claudin-5, iNOS, occludin and ZO-1 proteins are used for research. The results of our research show that 3 drugs can reduce the rate of cerebral infarction in rats, relieve the abnormal neuroethology of rats, reduce the degree of brain tissue lesion, increase the number of the Nissl corpuscle cells and repair the neuron ultrastructure in injured rats. At the same time, it can obviously reduce the ultrastructure damage of the BBB in rats. All three drugs significantly reduced the content of Evans blue in the ischemic brain tissue caused by cerebral ischemia in rats with BBB injury. In addition, E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid can decrease the protein expression of iNOS and MMP-9 in rat ischemic brain tissue. In addition, 3,5-dicaffeoylquinic acid can increase the protein expression of claudin-5. We conclude that E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid have obvious therapeutic effects on BBB and neuron injury induced by cerebral ischemia in rats. Our results from studying the mechanism of action show that E. breviscapus injection and Scutellarin inhibited the activation of MMP-9 by inhibiting the synthesis of iNOS, 3,5-dicaffeoylquinic acid inhibits the expression and activation of MMP-9 by inhibiting the activation of iNOS and reducing the generation of free radicals, thus reducing the degradation of important cytoskeleton connexin claudin-5 in the tight junction (TJ) structure by inhibiting the expression and activation of MMP-9. Finally BBB structure integrity was protected.

Scutellarin ameliorates high glucose-induced vascular endothelial cells injury by activating PINK1/Parkin-mediated mitophagy

ETHNOPHARMACOLOGICAL RELEVANCE

Scutellarin (Scu) is one of the main active ingredients of Erigeron breviscapus (Vant.) Hand.-Mazz which has been used to treat cardiovascular disease including vascular dysfunction caused by diabetes. Scu also has a protective effect on vascular endothelial cells against hyperglycemia. However, molecular mechanisms underlying this effect are not clear.

AIM OF THE STUDY

This aim of this study was to investigate the effect of Scu on human umbilical vein endothelial cells (HUVECs) injury induced by high glucose (HG), especially the regulation of PTEN-induced kinase 1 (PINK1)/Parkin-mediated mitophagy.

MATERIALS AND METHODS

HUVECs were exposed to HG to induce vascular endothelial cells injury in vitro. Cell viability was assessed by MTT assay. The extent of cell apoptosis was measured by Hoechst staining and flow cytometry. Mitophagy was assayed by fluorescent immunostaining, transmission electron microscope and immunoblot. Besides, virtual docking was conducted to validate the interaction of PINK1 protein and Scu.

RESULTS

We found that Scu significantly increased cell viability in HG-treated HUVECs. Scu reduces the expression of Bcl-2, Bax and cytochrome C (Cyt.c) to inhibit apoptosis through a mitochondria-dependent pathway. Meanwhile, Scu improved the overload of reactive oxygen species (ROS), superoxide dismutase (SOD) activity and SOD2 protein expression, and reversed the collapse of mitochondrial membrane potential. Besides, Scu increased autophagic flux, improved the expression of microtubule-associated protein 1 light chain 3 Ⅱ (LC3 II), Beclin 1 and autophagy-related gene 5 (Atg 5) and decreased the expression of Sequestosome1/P62 in HG-treated HUVECs. Furthermore, Scu improved the expressions of PINK1, Parkin, and Mitofusin2, which revealed the enhancement of mitophagy. Moreover, the beneficial effects of Scu on HG-induced low expression of Parkin, overproduction of ROS, and over expressions of P62, Cyt.c and Cleaved caspase-3 were weakened by PINK1 gene knockdown. Molecular docking suggested good interaction of Scu and PINK1 protein.

CONCLUSION

These results suggest that Scu may protect vascular endothelial cells against hyperglycemia-induced injury by up-regulating mitophagy via PINK1/Parkin signal pathway.

Antioxidant Vitamins and Prebiotic FOS and XOS Differentially Shift Microbiota Composition and Function and Improve Intestinal Epithelial Barrier In Vitro

Human gut microbiota (HGM) play a significant role in health and disease. Dietary components, including fiber, fat, proteins and micronutrients, can modulate HGM. Much research has been performed on conventional prebiotics such as fructooligosaccharides (FOS) and galactooligosaccharides (GOS), however, novel prebiotics or micronutrients still require further validation. We assessed the effect of FOS, xylooligosaccharides (XOS) and a mixture of an antioxidant vitamin blend (AOB) on gut microbiota composition and activity, and intestinal barrier in vitro. We used batch fermentations and tested the short-term effect of different products on microbial activity in six donors. Next, fecal inocula from two donors were used to inoculate the simulator of the human microbial ecosystem (SHIME) and after long-term exposure of FOS, XOS and AOB, microbial activity (short- and branched-chain fatty acids and lactate) and HGM composition were evaluated. Finally, in vitro assessment of intestinal barrier was performed in a Transwell setup of differentiated Caco-2 and HT29-MTX-E12 cells exposed to fermentation supernatants. Despite some donor-dependent differences, all three tested products showed beneficial modulatory effects on microbial activity represented by an increase in lactate and SCFA levels (acetate, butyrate and to a lesser extent also propionate), while decreasing proteolytic markers. Bifidogenic effect of XOS was consistent, while AOB supplementation appears to exert a specific impact on reducing F. nucleatum and increasing butyrate-producing B. wexlerae. Functional and compositional microbial changes were translated to an in vitro host response by increases of the intestinal barrier integrity by all the products and a decrease of the redox potential by AOB supplementation.

Glucuronomannan GM2 from Saccharina japonica Enhanced Mitochondrial Function and Autophagy in a Parkinson's Model

Parkinson's disease (PD), one of the most common neurodegenerative disorders, is caused by dopamine depletion in the striatum and dopaminergic neuron degeneration in the substantia nigra. In our previous study, we hydrolyzed the fucoidan from Saccharina japonica, obtaining three glucuronomannan oligosaccharides (GMn; GM1, GM2, and GM3) and found that GMn ameliorated behavioral deficits in Parkinsonism mice and downregulated the apoptotic signaling pathway, especially with GM2 showing a more effective role in neuroprotection. However, the neuroprotective mechanism is unclear. Therefore, in this study, we aimed to assess the neuroprotective effects of GM2 in vivo and in vitro. We applied GM2 in 1-methyl-4-phenylpyridinium (MPP+)-treated PC12 cells, and the results showed that GM2 markedly improved the cell viability and mitochondrial membrane potential, inhibited MPP+-induced apoptosis, and enhanced autophagy. Furthermore, GM2 contributed to reducing the loss of dopaminergic neurons in 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mice through enhancing autophagy. These data indicate that a possible protection of mitochondria and upregulation of autophagy might underlie the observed neuroprotective effects, suggesting that GM2 has potential as a promising multifunctional lead disease-modifying therapy for PD. These findings might pave the way for additional treatment strategies utilizing carbohydrate drugs in PD.

Scutellarin Inhibits the Growth and EMT of Gastric Cancer Cells through Regulating PTEN/PI3K Pathway

Gastric cancer is one of the most common malignancies with a high mortality rate world. This study intends to make clear the role and mechanism of the Scutellarin (Scu), a flavonoid isolated from Erigeron breviscapus (Vant.) Hand.-Mazz, in regulating the evolvement of gastric cancer. We selected different doses of Scu to treat gastric cancer cells (MGC-803 and AGS). Then, cell counting kit-8 (CCK8) assay was conducted to verify the proliferation of tumor cells, while flow cytometry was adopted to test the apoptosis rate. Meanwhile, Western blot was conducted to examine epithelial-mesenchymal transition (EMT) markers and the expression of phosphatase and tensin homolog (PTEN)/phosphatidylinositol 3-kinase (PI3K) and apoptosis-related proteins (Bax, Bcl2 and Caspase3). Moreover, xenograft tumor experiment in nude mice was established to verify the effect of Scu on tumor growth. Furthermore, the knockdown model of PTEN was constructed, and the influence of PTEN on the anti-tumor effect of Scu was investigated. As a result, Scu inhibited cell proliferation, EMT and promoted the apoptosis in gastric cancer dose-dependently. Additionally, Scu attenuated tumor cell growth in vivo. Besides, Scu enhanced the expression of PTEN while reduced the phosphorylated level of PI3K. Moreover, the mechanistic study proved that Scu inactivated PI3K by up-regulating PTEN, thus dampening tumor progression. In conclusion, Scu dampened the growth and EMT of gastric cancer by regulating the PTEN/PI3K pathway.

Characterization of Aspergillus niger MK981235 xylanase with extraction of anti-hepatotoxic, antioxidant, hypocholesterolemic and prebiotic Corchorus olitorius stems xylooligosaccharides

The object of this study was to utilize agro-industrial waste Corchorus olitorius stems (molokhia stems, MS) as substrate, for Aspergillus niger MK981235 xylanase production and as source of biologically active xylooligosaccharides (XOS). This study succeeded in utilization of Aspergillus niger MK981235 xylanase under different saccharification conditions designed by central composite design (CCD) for extraction of 15 biologically active XOS (anti-hepatotoxic, antioxidant, hypocholesterolemic and prebiotic) with different monosaccharides constituents composition and percent. A. niger MK981235 xylanase showed the highest activity 6.60 U·ml^-1 at 50 °C with 1.5% xylan. The kinetics included K_m and V_max were determined to be 6.67 mg·ml^-1 and 20 μmol·ml^-1·min^-1, respectively. Moreover, A. niger MK981235 xylanase thermodynamics E_a (activation energy) and E_d (activation energy of denaturation) were determined to be 21.95 and 39.51 KJ·mol^-1, respectively. The highest prebiotic effect (growth promation) was exerted by the central MS XOS on Lactobacillus plantarum and Lactobacillus rhamnosus (125 and 135.3%, respectively). Also, the central MS XOS, exerted the highest cholesterol reduction and antioxidant activities 74.7 and 92%, respectively, showed remarkable in vivo protective role against the hepatic toxicity of lithium carbonate evaluated by changes in body weight, liver function markers (AST, ALT, Alb, total bilirubin) and tissue makers (MDA and GSH).

Precise Regulation of the Basal PKCγ Activity by DGKγ Is Crucial for Motor Coordination

Diacylglycerol kinase γ (DGKγ) is a lipid kinase to convert diacylglycerol (DG) to phosphatidic acid (PA) and indirectly regulates protein kinase C γ (PKCγ) activity. We previously reported that the basal PKCγ upregulation impairs cerebellar long-term depression (LTD) in the conventional DGKγ knockout (KO) mice. However, the precise mechanism in impaired cerebellar LTD by upregulated PKCγ has not been clearly understood. Therefore, we first produced Purkinje cell-specific DGKγ KO (tm1d) mice to investigate the specific function of DGKγ in Purkinje cells and confirmed that tm1d mice showed cerebellar motor dysfunction in the rotarod and beam tests, and the basal PKCγ upregulation but not PKCα in the cerebellum of tm1d mice. Then, the LTD-induced chemical stimulation, K-glu (50 mM KCl + 100 µM, did not induce phosphorylation of PKCα and dissociation of GluR2 and glutamate receptor interacting protein (GRIP) in the acute cerebellar slices of tm1d mice. Furthermore, treatment with the PKCγ inhibitor, scutellarin, rescued cerebellar LTD, with the phosphorylation of PKCα and the dissociation of GluR2 and GRIP. In addition, nonselective transient receptor potential cation channel type 3 (TRPC3) was negatively regulated by upregulated PKCγ. These results demonstrated that DGKγ contributes to cerebellar LTD by regulation of the basal PKCγ activity.

Prebiotic Xylo-Oligosaccharides Ameliorate High-Fat-Diet-Induced Hepatic Steatosis in Rats

Understanding the importance of the gut microbiota (GM) in non-alcoholic fatty liver disease (NAFLD) has raised the hope for therapeutic microbes. We have shown that high hepatic fat content associated with low abundance of Faecalibacterium prausnitzii in humans and, further, the administration of F. prausnitzii prevented NAFLD in mice. Here, we aimed at targeting F. prausnitzii by prebiotic xylo-oligosaccharides (XOS) to treat NAFLD. First, the effect of XOS on F. prausnitzii growth was assessed in vitro. Then, XOS was supplemented or not with high (HFD, 60% of energy from fat) or low (LFD) fat diet for 12 weeks in Wistar rats (n = 10/group). XOS increased F. prausnitzii growth, having only a minor impact on the GM composition. When supplemented with HFD, XOS ameliorated hepatic steatosis. The underlying mechanisms involved enhanced hepatic β-oxidation and mitochondrial respiration. Nuclear magnetic resonance (¹H-NMR) analysis of cecal metabolites showed that, compared to the HFD, the LFD group had a healthier cecal short-chain fatty acid profile and on the HFD, XOS reduced cecal isovalerate and tyrosine, metabolites previously linked to NAFLD. Cecal branched-chain fatty acids associated positively and butyrate negatively with hepatic triglycerides. In conclusion, XOS supplementation can ameliorate NAFLD by improving hepatic oxidative metabolism and affecting GM.

Virucidal Efficacy of Olanexidine Gluconate as a Hand Antiseptic Against Human Norovirus

Human noroviruses are the major cause of non-bacterial acute gastroenteritis worldwide. Since no therapeutic agent has been proven to prevent human norovirus infection yet, preventive healthcare interventions to block the infection routes play an important role in infection control. One of the possible infection routes of human noroviruses are through contaminated hands, but no hand antiseptics have been proven effective. Olanexidine gluconate is a new biguanide compound that has already been approved for sale as an antiseptic for the surgical field in Japan. A new hand antiseptic was developed using olanexidine gluconate in this study, and its virucidal efficacy against human noroviruses was evaluated using modified RT-qPCR that can account for genome derived from intact viruses using RNase A and photo-reactive intercalators. We tested the virucidal efficacy of five materials; two olanexidine gluconate antiseptics (hand rub formulation and surgical field formulation), two kinds of ethanol solutions at different pH (approx. 3 or 7), and a base component of olanexidine gluconate hand rub formulation against 11 human norovirus genotypes by culture-independent methods. The infectivity of murine norovirus (MNV), a surrogate for human norovirus, was significantly reduced after use of the antiseptics. The olanexidine gluconate hand rub demonstrated the strongest virucidal efficacy against human norovirus among the five tested materials. This study showed that olanexidine gluconate has the potential to become a strong tool for the prevention of human norovirus infection.

Oral Supplements of Combined Bacillus licheniformis Zhengchangsheng® and Xylooligosaccharides Improve High-Fat Diet-Induced Obesity and Modulate the Gut Microbiota in Rats

Gut dysbiosis induced by high-fat diet (HFD) may result in low-grade inflammation leading to diverse inflammatory diseases. The beneficial effects of probiotics and prebiotics on obesity have been reported previously. However, their benefits in promoting human health and the underlying mechanisms still need to be further characterized. This study is aimed at understanding how probiotic Bacillus licheniformis Zhengchangsheng® (BL) and prebiotic xylooligosaccharides (XOS) influence the health of a rat model with HF (60 kcal %) diet-induced obesity. Five groups of male Sprague Dawley (SD) rats were fed a normal fat diet (CON) or an HFD with or without BL and XOS supplementation for 3 weeks. Lipid profiles, inflammatory biomarkers, and microbiota composition were analyzed at the end of the experiment. Rats fed an HFD exhibited increased body weight and disordered lipid metabolism. In contrast, combined BL and XOS supplementation inhibited body weight gain and returned lipid metabolism to normal. Furthermore, BL and XOS administration changed the gut microbiota composition and modulated specific bacteria such as Prevotellaceae, Desulfovibrionaceae, and Ruminococcaceae. In addition, supplements of combined BL and XOS obviously reduced the serum LPS level, which was significantly related to microbial variations. Our findings suggest that modulation of the gut microbiota as a result of probiotic BL and prebiotic XOS supplementation has a positive effect on HFD-induced obesity in rats.

Scutellarin protects against myocardial ischemia-reperfusion injury by suppressing NLRP3 inflammasome activation

BACKGROUND

Activation of NLRP3 inflammasome plays a key role in cardiac dysfunction for acute myocardial ischemia-reperfusion injury. Scutellarin (Scu) is a flavonoid purified from Erigeron breviscapus. Whether Scu has any influence on the activation of NLRP3 inflammasome in cardiomyocytes remains unknown.

PURPOSE

We aimed to examine the therapeutic effect of Scu on cardiomyocyte ischemia-reperfusion (I/R) injury and its effect on NLRP3 inflammasome in rats with acute myocardial I/R injury and anoxia/reoxygenation (A/R)-induced H9c2 injuries.

METHODS

Heart injuries were induced through 30 min of ischemia followed by 24 h of reperfusion. Scu was intraperitoneally administered 15 min before vascular ligation. Effects of Scu on cardiac injury were detected by echocardiograms, TTC staining, and histological and immunohistochemical analyses. The effects of Scu on biochemical parameters were analyzed. H9c2 cells were pretreated with different concentrations of Scu for 6 h before A/R exposure. Afterward, cell viability, LDH release, and Hoechst 33342 and peromide iodine double staining were determined. Western blot analyses of proteins, including those involved in autophagy, NLRP3, mTOR complex 1 (mTORC1), and Akt signaling, were conducted.

RESULTS

In vivo study revealed that Scu improved diastolic dysfunction, ameliorated myocardium structure abnormality, inhibited myocyte apoptosis and inflammatory response, and promoted autophagy. Scu reduced NLRP3 inflammasome activation, inhibited mTORC1 activity, and increased Akt phosphorylation. In vitro investigation showed the same results. The Scu-mediated NLRP3 inflammasome and mTORC1 inhibition and cardioprotection were abolished through the genetic silencing of Akt by siRNA.

CONCLUSIONS

The cardioprotective effect of Scu was achieved through its anti-inflammatory effect. It suppressed the activation of NLRP3 inflammasome. In addition, inflammasome restriction by Scu was dependent on Akt activation and mTORC1 inhibition.

Scutellarin exerts anticancer effects on human leukemia cells via induction of Sub-G1 cell cycle arrest, apoptosis and also inhibits migration and invasion by targeting Raf/MEK/ERK signalling pathway

PURPOSE

Leukemia accounts for a significant mortality across the globe every year. The main objective of the present research work was directed towards studying the anticancer effects of scutellarin-a plant flavone, against K562 human leukemia cells, along with examining its effects on cellular apoptosis, cell cycle, cell migration and cell invasion as well as Raf/MEK/ERK signalling pathway.

METHODS

Cell viability of K562 leukemia cells was evaluated by WTS-1 assay, while apoptotic effects induced by scutellarin in K562 cells were examined by fluorescence microscopy, flow cytometry, and western blot methods. Effects on cell cycle were measured by flow cytometry. Transwell Matrigel assay was performed to evaluate whether scutellarin induces inhibition of cell migration and cell invasion effects in K562 cells.

RESULTS

Scutellarin was shown to suppress the viability of the K562 cells dose-dependently with an IC50 of 6 μM. Further, scutellarin was shown to induce apoptosis which was initially exhibited by DAPI and annexin-V/propidium iodide (PI) staining and then confirmed by western blot in which it was shown to trigger regulation of Bax and downregulation of Bcl-2 in K562 human leukemia cells. Scutellarin also induced G0/G1 cell cycle arrest which was accompanied by suppression of cell migration and invasion. Scutellarin also led to the decline of the expression of p-Raf, p-MEK1/2 and p-ERK1/2 in a concentration-dependent manner.

CONCLUSION

In conclusion, scutellarin could inhibit the growth of K562 human leukemia cells by inducing apoptosis, cell cycle arrest, inhibition of cell migration and invasion and downregulating the expressions of p-Raf, p-MEK1/2 and p-ERK1/2.

Inhibitory Effects of Eriodictyol-7-O-β-d-glucuronide and 5,7-Dihydroxy-4-chromene Isolated from Chrysanthemum zawadskii var. latilobum in FcεRI-Mediated Human Basophilic KU812F Cell Activation

Chrysanthemum zawadskii var. latilobum (CZL) has been used in Eastern medicine for the treatment of various diseases, such as pneumonia, bronchitis, cough, the common cold, pharyngitis, bladder-related disorders, gastroenteric disorders, and hypertension. In the present study, we isolated two strong antiallergic compounds from CZL, namely, eriodictyol-7-O-β-d-glucuronide (EDG) and 5,7-dihydroxy-4-chromene (DC), and investigated their antiallergic effects in FcεRI-mediated human basophilic KU812F cells. EDG and DC downregulated the protein and messenger RNA (mRNA) expression of FcεRI on the cell surface. Moreover, Western blotting analysis showed that EDG and DC inhibited the expression of protein tyrosine kinases such as Syk and Lyn, and extracellular-regulated kinases (ERK) 1/2. These results suggested that EDG and DC, antiallergic constituents of CZL, are potential therapeutic candidates for protection against and for the treatment of allergic disorders.

In Silico and In Vitro Anti-Helicobacter Pylori Effects of Combinations of Phytochemicals and Antibiotics

Helicobacter pylori infection is a WHO class 1 carcinogenic factor of gastric adenocarcinoma. In the past decades, many studies have demonstrated the increasing trend of antibiotic resistance and pointed out the necessity of new effective treatment. This study was aimed at identifying phytochemicals that can inhibit H. pylori and possibly serve as adjuvant treatments. Here, in silico molecular docking and drug-like properties analyses were performed to identify potential inhibitors of urease, shikimate kinase and aspartate-semialdehyde dehydrogenase. These three enzymes are targets of the treatment of H. pylori. Susceptibility and synergistic testing were performed on the selected phytochemicals and the positive control antibiotic, amoxicillin. The in-silico study revealed that oroxindin, rosmarinic acid and verbascoside are inhibitors of urease, shikimate kinase and aspartate-semialdehyde dehydrogenase, respectively, in which, oroxindin has the highest potency against H. pylori, indicated by a minimum inhibitory concentration (MIC) value of 50 μg/mL. A combination of oroxindin and amoxicillin demonstrated additive effects against H. pylori, as indicated by a fractional inhibitory concentration (FIC) value of 0.75. This study identified phytochemicals that deserve further investigation for the development of adjuvant therapeutic agents to current antibiotics against H. pylori.

Scutellarin inhibits the invasive potential of malignant melanoma cells through the suppression epithelial-mesenchymal transition and angiogenesis via the PI3K/Akt/mTOR signaling pathway

Malignant melanoma is the leading cause of death from skin disease, due in large part to its propensity to metastasize. Scutellarin is an active flavone extracted from traditional Chinese herb Erigeron breviscapus (Vant.) Hand. Mazz. Recent studies have reported that scutellarin can be utilized to treat various types of tumors. In this study, we investigated the effects of scutellarin on melanoma cancer cell invasive potential and the molecular mechanisms underlying these effects using A375 melanoma cells lines. The in-vitro antitumor activity of scutellarin was evaluated by CCK-8 assay, wound-healing assay, transwell assays, adhesion assays, and tube formation assays to assess the cell viability, migration, invasion, adhesion, and angiogenesis, respectively. Also, western blotting assay was used to assess the level of PI3K/Akt/mTOR signaling pathway proteins in A375 cells. We found that scutellarin significantly inhibited melanoma cell lines and HUVECs viability in a time- and concentration-dependent manners. Additionally, scutellarin effectively suppressed tumor cell migration, invasion, adhesion through the suppression of EMT and angiogenesis by inhibiting the PI3K/Akt/mTOR signaling pathway. These results indicated that scutellarin could markedly inhibit the invasive potential of melanoma cell lines by suppressing the EMT and angiogenesis through the PI3K/Akt/mTOR signaling pathway. It suggests that scutellarin might be a potential compound in malignant melanoma treatment.

Scutellarin Prevents Angiogenesis in Diabetic Retinopathy by Downregulating VEGF/ERK/FAK/Src Pathway Signaling

BACKGROUND

Diabetic retinopathy (DR) is a serious microvascular complication of diabetes. This study demonstrates the antiangiogenic effects of scutellarin (SCU) on high glucose- and hypoxia-stimulated human retinal endothelial cells (HRECs) and on a diabetic rat model by oral administration. The antiangiogenic mechanisms of SCU in vitro and in vivo were investigated.

METHOD

HRECs were cultured in high glucose- (30 mM D-glucose) and hypoxia (cobalt chloride-treated)-stimulated diabetic condition to evaluate the antiangiogenic effects of SCU by CCK-8 test, cell migration experiment (wound healing and transwell), and tube formation experiment. A streptozotocin-induced type II diabetic rat model was established to measure the effects of oral administration of SCU on protecting retinal microvascular dysfunction by Doppler waveforms and HE staining. We further used western blot, luciferase reporter assay, and immunofluorescence staining to study the antiangiogenic mechanism of SCU. The protein levels of phospho-ERK, phospho-FAK, phospho-Src, VEGF, and PEDF were examined in HRECs and retina of diabetic rats.

RESULT

Our results indicated that SCU attenuated diabetes-induced HREC proliferation, migration, and tube formation and decreased neovascularization and resistive index in the retina of diabetic rats by oral administration. SCU suppressed the crosstalk of phospho-ERK, phospho-FAK, phospho-Src, and VEGF in vivo and in vitro.

CONCLUSIONS

These results suggested that SCU can be an oral drug to alleviate microvascular dysfunction of DR and exerts its antiangiogenic effects by inhibiting the expression of the crosstalk of VEGF, p-ERK, p-FAK, and p-Src.

Structural Features of Sulfated Glucuronomannan Oligosaccharides and Their Antioxidant Activity

Glucuronomannan oligosaccharides (Gs) were derived from fucoidan, which was extracted from the brown alga Sargassum thunbergii. Sulfated glucuronomannan oligosaccharides (SGs) were obtained by the sulfation of Gs. NMR techniques were used to reveal that the order of sulfation was Man-C6 > Man-C4 > Man-C1R > GlcA-C3 > Man-C3 > GlcA-C2. Finally, the antioxidant activities (hydroxyl radical scavenging activity, superoxide radical scavenging activity, reducing power and DPPH radical scavenging activity) of Gs and SGs were determined. The findings showed that the higher the degree of polymerization, the better the activity, except for the hydroxyl radical scavenging activity. In addition, the higher the sulfate content, the lower the activities for the reducing power and DPPH radical scavenging activity. Opposite results were found for the superoxide radical scavenging activity. Finally, compared with fucoidan, most Gs and SGs had higher antioxidant activity, suggesting that they might be good candidates for antioxidants.

How Fine Structural Differences of Xylooligosaccharides and Arabinoxylooligosaccharides Regulate Differential Growth of Bacteroides Species

Xylooligosaccharides (XOS) and arabinoxylooligosaccharides (AXOS) could be used to selectively favor growth of certain gut bacterial groups. The objective of this research was to understand how the structural differences of XOS and AXOS influenced the growth of Bacteroides species commonly found in the intestine. We report that the specific structural details of XOS and AXOS dictate the differential growth of Bacteroides species in the intestine. We also investigated the expression of two polysaccharide utilization loci (PULs) in a strain of Bacteroides ovatus upon growth on AXOS using three different susC transcripts as sentinel reporter genes. 2³-α-l-Arabinofuranosyl-xylotriose (A4) was shown to upregulate small xylan PUL gene expression, while 2³,3³-di-α-l-arabinofuranosyl-xylotriose (A6) decreased expression of this PUL. These results reveal new details about the potentially very specific structure-function relationship of XOS and AXOS that could be used in targeted alteration of the microbial population in the gut through dietary interventions to maintain health.

Scutellarin suppresses neuroinflammation via the inhibition of the AKT/NF-κB and p38/JNK pathway in LPS-induced BV-2 microglial cells

In vitro and in vivo studies indicate that scutellarin (SCU) exerts anti-inflammatory effects in the central nervous system (CNS) and inhibits microglia activation. This study investigated the anti-neuroinflammation molecular mechanisms exerted by scutellarin in LPS-induced BV-2 cells. The results showed that production of TNF-α, IL-1β, IL-6, and NO and TNF-α, IL-1β, IL-6, and iNOS mRNA were inhibited by scutellarin, which was independent of cytotoxicity as assessed by a CCK8 assay. Western blot analysis indicated that NF-κB-p65 phosphorylation was suppressed by scutellarin via inhibition of IκB degradation and IKKβ activation, which coincided with blockage of nuclear translocation of NF-κB as shown by immunofluorescent staining. Consistent with the inhibition of NF-κB, scutellarin inhibited the phosphorylation of p38, JNK, and AKT without affecting phosphorylation of ERK1/2 or PI3K in LPS-induced BV-2 cells. Overall, the present study suggests that scutellarin inhibits the production of pro-inflammatory mediators via inhibition of the IKK-dependent NF-κB and p38/JNK signaling pathway, which inhibits microglia activation and exerts anti-inflammation, indicating its potential therapeutic effect for neurodegenerative and cerebrovascular diseases.

Scutellarin Mitigates Aβ-Induced Neurotoxicity and Improves Behavior Impairments in AD Mice

Alzheimer’s disease (AD) is pathologically characterized by excessive accumulation of amyloid-beta (Aβ) within extracellular spaces of the brain. Aggregation of Aβ has been shown to trigger oxidative stress, inflammation, and neurotoxicity resulting in cognitive dysfunction. In this study, we use models of cerebral Aβ amyloidosis to investigate anti-amyloidogenic effects of scutellarin in vitro and in vivo. Our results show that scutellarin, through binding to Aβ42, efficiently inhibits oligomerization as well as fibril formation and reduces Aβ oligomer-induced neuronal toxicity in cell line SH-SY5Y. After nine months of treatment in APP/PS1 double-transgenic mice, scutellarin significantly improves behavior, reduces soluble and insoluble Aβ levels in the brain and plasma, decreases Aβ plaque associated gliosis and levels of proinflammatory cytokines TNF-α and IL-6, attenuates neuroinflammation, displays anti-amyloidogenic effects, and highlights the beneficial effects of intervention on development or progression of AD-like neuropathology.

Prebiotic prevents impaired kidney and renal Oat3 functions in obese rats

Obesity is health issue worldwide, which can lead to kidney dysfunction. Prebiotics are non-digestible foods that have beneficial effects on health. This study aimed to investigate the effects of xylooligosaccharide (XOS) on renal function, renal organic anion transporter 3 (Oat3) and the mechanisms involved. High-fat diet was provided for 12 weeks in male Wistar rats. After that, the rats were divided into normal diet (ND); normal diet treated with XOS (NDX); high-fat diet (HF) and high-fat diet treated with XOS (HFX). XOS was given daily at a dose of 1000 mg for 12 weeks. At week 24, HF rats showed a significant increase in obesity and insulin resistance associated with podocyte injury, increased microalbuminuria, decreased creatinine clearance and impaired Oat3 function. These alterations were improved by XOS supplementation. Renal MDA level and the expression of AT1R, NOX4, p67^phox, 4-HNE, phosphorylated PKCα and ERK1/2 were significantly decreased after XOS treatment. In addition, Nrf2-Keap1 pathway, SOD2 and GCLC expression as well as renal apoptosis were also significantly reduced by XOS. These data suggest that XOS could indirectly restore renal function and Oat3 function via the reduction of oxidative stress and apoptosis through the modulating of AT1R-PKCα-NOXs activation in obese insulin-resistant rats. These attenuations were instigated by the improvement of obesity, hyperlipidemia and insulin resistance.

Scutellarin protects against vascular endothelial dysfunction and prevents atherosclerosis via antioxidation

BACKGROUND

Scutellarin is the major constituent responsible for the clinical benefits of Erigeron breviscapus (Vant.) Hand.-Mazz which finds a long history of ethnopharmacological use in Traditional Chinese Medicine. Scutellarin as a pure compound is now under investigation for its protections against various tissue injuries.

PURPOSE

This study aims to examine the effects of scutellarin on oxidative stress-induced vascular endothelial dysfunction and endothelial cell damage, and then to evaluate the therapeutic efficacy of scutellarin in preventing atherosclerosis in rats.

METHODS

Radical scavenging ability of scutellarin was determined in vitro. Impact of scutellarin on endothelium-dependent relaxation (EDR) of rabbit thoracic aortic rings upon 1, 1-diphenyl-2-picrylhydrazyl (DPPH) challenge was measured. Influences of scutellarin pre-treatment on the levels of reactive oxygen species (ROS), activities of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase and catalase, and the expression of SOD1 and NADPH oxidase 4 (Nox4) in human umbilical vein endothelial cells (HUVECs) injured by H₂O₂ were examined. Anti-atherosclerotic effect of scutellarin was evaluated in rats fed with high fat diet (HFD).

RESULTS

Scutellarin showed potent antioxidant activity in vitro. Pretreatment of scutellarin retained the EDR of rabbit thoracic aortic rings damaged by DPPH. In H₂O₂ injured-HUVECs the deleterious alterations in ROS levels and antioxidant enzymes activity were reversed by scutellarin and the mRNA and protein expression of SOD1 and Nox4 were restored also. Oral administration of scutellarin dose-dependently ameliorated hyperlipidemia in HFD-fed rats and alleviated oxidative stress in rat serum, mimicking the effects of reference drug atorvastatin.

CONCLUSION

Scutellarin protects against oxidative stress-induced vascular endothelial dysfunction and endothelial cell damage in vitro and prevents atherosclerosis in vivo through antioxidation. The results rationalize further investigation into the clinical use of scutellarin in cardiovascular diseases.

Synthesis of Scutellarein Derivatives with a Long Aliphatic Chain and Their Biological Evaluation against Human Cancer Cells

Scutellarin is the major active flavonoid extracted from the traditional Chinese herbal medicine Erigeron breviscapus (Vant.) Hand-Mazz., which is widely used in China. Recently, accumulating evidence has highlighted the potential role of scutellarin and its main metabolite scutellarein in the treatment of cancer. To explore novel anticancer agents with high efficiency, a series of new scutellarein derivatives with a long aliphatic chain were synthesized, and the antiproliferative activities against Jurkat, HCT-116 and MDA-MB-231 cancer cell lines were assessed. Among them, compound 6a exhibited the strongest antiproliferative effects on Jurkat (IC₅₀ = 1.80 μM), HCT-116 (IC₅₀ = 11.50 μM) and MDA-MB-231 (IC₅₀ = 53.91 μM). In particular, 6a even showed stronger antiproliferative effects than the positive control NaAsO₂ on Jurkat and HCT-116 cell lines. The results showed that a proper long aliphatic chain enhanced the antiproliferative activity of scutellarein.

Synthesis and Bioactivity Characterization of Scutellarein Sulfonated Derivative

Scutellarin (1) has been widely used to treat acute cerebral infarction in clinic, but poor aqueous solubility decreases its bioavailability. Interestingly, scutellarin (1) could be metabolized into scutellarein (2) in vivo. In this study, a sulfonic group was introduced at position C-8 of scutellarein (2) to enhance the aqueous solubility of the obtained derivative (3). DPPH (1,1-diphenyl-2-picrylhydrazyl)-radical scavenging ability and antithrombic activity were also conducted to determine its bioactivity. The result showed that scutellarein derivate (3) could be a better agent for ischemic cerebrovascular disease treatment.

Scutellarin inhibits RANKL-mediated osteoclastogenesis and titanium particle-induced osteolysis via suppression of NF-κB and MAPK signaling pathway

Aseptic prosthetic loosening is a major complication after hip joint replacement. Wear particle-induced periprosthetic osteolysis plays a key role in aseptic prosthetic loosening. Attempting to modulate receptor activator of nuclear factor-κB (RANKL) mediated signaling pathways is a promising strategy to prevent aseptic prosthetic loosening. In the present study, we determined the effect of scutellarin (SCU) on titanium (Ti) particle-induced osteolysis in a mouse calvarial model and RANKL-mediated osteoclastogenesis. We determined that SCU, the major effective constituent of breviscapine isolated from a Chinese herb, has potential effects on preventing Ti particle-caused osteolysis in calvarial model of mouse. In vitro, SCU could suppress RANKL-mediated osteoclastogenesis, the function of osteoclast bone resorption, and the expression levels of osteoclast-specific genes (tartrate-resistant acid phosphatase (TRAP), cathepsin K, c-Fos, NFATc1). Further investigation indicated that SCU could inhibit RANKL-mediated MAPK and NF-κB signaling pathway, including JNK1/2, p38, ERK1/2, and IκBα phosphorylation. Taken together, these results indicate that SCU could inhibit osteoclastogenesis and prevent Ti particle-induced osteolysis by suppressing RANKL-mediated MAPK and NF-κB signaling pathway. These results suggest that SCU is a promising therapeutic agent for preventing wear particle-induced periprosthetic osteolysis.

Pharmacokinetic Comparison of Scutellarin and Paeoniflorin in Sham-Operated and Middle Cerebral Artery Occlusion Ischemia and Reperfusion Injury Rats after Intravenous Administration of Xin-Shao Formula

Xin-Shao formula is a folk remedy widely used in China to prevent and cure stroke. Cerebral ischemic reperfusion (I/R) injury often takes place during the treatment of stroke. Information about the pharmacokinetic behavior of the remedy under cerebral I/R injury conditions is lacking. The present study aimed to compare the pharmacokinetic properties of scutellarin and paeoniflorin, two major bioactive components of Xin-Shao formula, under physiological state in cerebral I/R injury rats. Neurobehavioral dysfunction was evaluated and cerebral infarcted volume was measured in middle cerebral artery occlusion I/R injury (MCAO) rats. Plasma samples were collected at various time points after a single dose (intravenous, i.v.) of Xin-Shao formula. The levels of plasma scutellarin and paeoniflorin at the designed time points were determined by a UPLC-MS/MS method, and drug concentration versus time plots were constructed to estimate pharmacokinetic parameters. Increase in terminal elimination half-life (t_1/2z) and mean residence time (MRT_(0–t)) of scutellarin as well as elevation in area under the plasma drug concentration-time curve from 0 h to the terminal time point (AUC_(0–t)) and maximum plasma drug concentration (C_max) of paeoniflorin, along with decreased clearance of paeoniflorin and scutellarin as well as reduced apparent volume of distribution (V_z) of paeoniflorin, were observed in MCAO rats, compared with those in sham-operated animals. The elimination of scutellarin and paeoniflorin were reduced in cerebral I/R injury reduced rats.

Scutellarin attenuates endothelium-dependent aasodilation impairment induced by hypoxia reoxygenation, through regulating the PKG signaling pathway in rat coronary artery

Scutellarin (SCU), a flavonoid from a traditional Chinese medicinal plant. Our previous study has demonstrated that SCU relaxes mouse aortic arteries mainly in an endothelium-depend-ent manner. In the present study, we investigated the vasoprotective effects of SCU against HR-induced endothelial dysfunction (ED) in isolated rat CA and the possible mechanisms involving cyclic guanosine monophosphate (cGMP) dependent protein kinase (PKG). The isolated endothelium-intact and endothelium-denuded rat CA rings were treated with HR injury. Evaluation of endothelium-dependent and -independent vasodilation relaxation of the CA rings were performed using wire myography and the protein expressions were assayed by Western blotting. SCU (10-1 000 μmol·L(-1)) could relax the endothelium-intact CA rings but not endothelium-denuded ones. In the intact CA rings, the PKG inhibitor, Rp-8-Br-cGMPS (PKGI-rp, 4 μmol·L(-1)), significantly blocked SCU (10-1 000 μmol·L(-1))-induced relaxation. The NO synthase (NOS) inhibitor, NO-nitro-L-arginine methylester (L-NAME, 100 μmol·L(-1)), did not significantly change the effects of SCU (10-1 000 μmol·L(-1)). HR treatment significantly impaired ACh-induced relaxation, which was reversed by pre-incubation with SCU (500 μmol·L(-1)), while HR treatment did not altered NTG-induced vasodilation. PKGI-rp (4 μmol·L(-1)) blocked the protective effects of SCU in HR-treated CA rings. Additionally, HR treatment reduced phosphorylated vasodilator-stimulated phosphoprotein (p-VASP, phosphorylated product of PKG), which was reversed by SCU pre-incubation, suggesting that SCU activated PKG phosphorylation against HR injury. SCU induces CA vasodilation in an endothelium-dependent manner to and repairs HR-induced impairment via activation of PKG signaling pathway.

Neuroprotective Effect of Scutellarin on Ischemic Cerebral Injury by Down-Regulating the Expression of Angiotensin-Converting Enzyme and AT1 Receptor

Background and Purpose

Previous studies have demonstrated that angiotensin-converting enzyme (ACE) is involved in brain ischemic injury. In the present study, we investigated whether Scutellarin (Scu) exerts neuroprotective effects by down-regulating the Expression of Angiotensin-Converting Enzyme and AT1 receptor in a rat model of permanent focal cerebral ischemia.

Methods

Adult Sprague–Dawley rats were administrated with different dosages of Scu by oral gavage for 7 days and underwent permanent middle cerebral artery occlusion (pMCAO). Blood pressure was measured 7 days after Scu administration and 24 h after pMCAO surgery by using a noninvasive tail cuff method. Cerebral blood flow (CBF) was determined by Laser Doppler perfusion monitor and the neuronal dysfunction was evaluated by analysis of neurological deficits before being sacrificed at 24 h after pMCAO. Histopathological change, cell apoptosis and infarct area were respectively determined by hematoxylin–eosin staining, terminal deoxynucleotidyl transfer-mediated dUTP nick end labeling (TUNEL) analysis and 2,3,5-triphenyltetrazolium chloride staining. Tissue angiotensin II (Ang II) and ACE activity were detected by enzyme-linked immunosorbent assays. The expression levels of ACE, Ang II type 1 receptor (AT1R), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) were measured by Western blot and real-time PCR. ACE inhibitory activity of Scu in vitro was detected by the photometric determination.

Results

Scu treatment dose-dependently decreased neurological deficit score, infarct area, cell apoptosis and morphological changes induced by pMCAO, which were associated with reductions of ACE and AT1R expression and the levels of Ang II, TNF-α, IL-6, and IL-1β in ischemic brains. Scu has a potent ACE inhibiting activity.

Conclusion

Scu protects brain from acute ischemic injury probably through its inhibitory effect on the ACE/Ang II/AT1 axis, CBF preservation and proinflammation inhibition.

Role of xylo-oligosaccharides in protection against salinity-induced adversities in Chinese cabbage

Soil salinity is a stringent abiotic constraint limiting crop growth and productivity. The present study was carried out to appraise the role of xylo-oligosaccharides (XOSs) in improving the salinity tolerance of Chinese cabbage. Salinity stress (0.5% NaCl solution) and four levels (0, 40, 80, 120 mg L(-1)) of XOSs were imposed on 20-day-old plants cultured under controlled conditions. Salinity stress decreased the aboveground fresh biomass, photosynthesis, transpiration rate, stomatal conductance, internal CO2 concentration, water use efficiency, and chlorophyll contents but increased the stomatal limitation value of Chinese cabbage compared with control. Such physiological interferences, disturbances in plant water relations, and visually noticeable growth reductions in Chinese cabbage were significantly alleviated by the addition of XOSs under salinity stress. Under salinity stress, application of XOSs significantly enhanced the activities of enzymatic (superoxide dismutase, peroxidase, catalase) and non-enzymatic (ascorbate, carotene) antioxidants and reduced the malondialdehyde content in the leaves of Chinese cabbage. The XOS-applied plants under salinity stress also recorded higher soluble sugars, proline, and soluble protein content in their leaves. Exposure of salinity stress increased the ratio of Na(+)/K(+), Na(+)/Ca(2+), and Na(+)/Mg(2+) in shoot as well as root of Chinese cabbage, however, XOS application significantly reduced these ratios particularly in shoot. Lower levels of XOSs (40 or 80 mg L(-1)) were more effective for most of the studied attributes. The greater salinity tolerance and better growth in these treatments were related with enhanced antioxidative defense system, reduced lipid peroxidation, increased osmolyte accumulation, and maintenance of ionic balance.

Scutellarin regulates microglia-mediated TNC1 astrocytic reaction and astrogliosis in cerebral ischemia in the adult rats

BACKGROUND

Scutellarin, an anti-inflammatory agent, effectively suppressed microglia activation in rats with middle cerebral artery occlusion (MCAO). Robust microglia activation, acute in onset, was followed by astrogliosis. This study was aimed to determine if scutellarin would also affect the reactive astrocytes that play an important role in tissue repair. Expression of GFAP and Notch-1 and its members: Notch receptor intracellular domain (NICD), and transcription factor hairy and enhancer of split-1 (HES-1), together with nestin and proinflammatory mediators was assessed by immunofluorescence staining in TNC1 astrocytes treated, respectively, with BV-2 conditioned medium (CM) and CM + lipopolysaccharide (LPS) (CM + L) serving as the controls, and conditioned medium derived from LPS-activated BV-2 cells pretreated with scutellarin (CM + SL). Study of the above biomarkers was then extended to reactive astrocytes in scutellarin injected MCAO rats.

RESULTS

TNC1 astrocytes remained relatively unreactive in terms of expression of different biomarkers to direct scutellarin treatment when compared with the control cells. In comparison to cells in the control medium (CM, CM + L), they responded vigorously to CM + SL as evidenced by the enhanced protein expression of GFAP, Notch-1, NICD and HES-1 coupled with that of nestin, TNF-α, IL-1β, and iNOS by Western and immunofluorescence analysis. Electron microscopy showed marked hypertrophy and cell expansion of TNC1 astrocytes bearing many filamentous processes indicative of enhanced astrocyte reaction when treated with CM + SL. In MCAO rats, scutellarin also augmented the expression of the above markers in reactive astrocytes; moreover, astrocytes were evidently hypertrophic.

CONCLUSIONS

The results suggest that scutellarin regulates astrogliosis; more importantly, it is microglia-mediated as demonstrated in vitro. Increased expression of Notch signaling in synchrony with nestin may be linked to proliferation and "de-differentiation" of reactive astrocytes; the significance of enhanced TNF-α, IL-1β and iNOS expression in reactive astrocytes by scutellarin may be neuroprotective but this remains speculative.

Comparative Metabolomic Analysis of the Neuroprotective Effects of Scutellarin and Scutellarein against Ischemic Insult

For more than thirty years, scutellarin (Scu) has been used in China to clinically treat acute cerebral infarction and paralysis. Scutellarein (Scue), the major Scu metabolite in vivo, exhibits heightened neuroprotective effects when compared to Scu. To explore the neuroprotective role of these compounds, we performed ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry (UHPLC-QTOF/MS) coupled with a pattern recognition approach to investigate metabolomic differences in a rat model of ischemia after treatment with each compound. We examined metabolites in urine, hippocampal tissue, and plasma, and we tentatively identified 23 endogenous metabolites whose levels differed significantly between sham-operated and model groups. Upon pathway analysis, we found an additional 11 metabolic pathways in urine, 14 metabolic pathways in the hippocampal tissue, and 3 metabolic pathways in plasma. These endogenous metabolites were mainly involved in sphingolipid metabolism, lysine biosynthesis, and alanine, aspartate, and glutamate metabolism. We found that metabolic changes after ischemic injury returned to near-normal levels after Scue intervention, unlike Scu treatment, further validating the heightened protective effects exerted by Scue compared to Scu. These results demonstrate that Scue is a potential drug for treatment of ischemic insult.

Scutellarin protects against the liver injury induced by diosbulbin B in mice and its mechanism

ETHNOPHARMACOLOGICAL RELEVANCE

Diosbulbin B (DB) is the main hepatotoxic compound distributed in Dioscorea bulbifera L., which is widely used for the treatment of cancer and thyroid disorders in Asia. Scutellarin (SC) is the main compound in medicinal herb Scutellaria barbata D. Don, which is usually combined with Dioscorea bulbifera used for cancer therapy in clinic.

AIM OF THE STUDY

This study aims to investigate the protection of SC against the liver injury induced by DB and its engaged mechanism. In addition, the anti-tumor effect of DB and SC is further observed in vivo.

MATERIALS AND METHODS

The protection of SC against DB-induced liver injury was evaluated by detecting serum alanine/aspartate aminotransferases (ALT/AST) and alkaline phosphatase (ALP) activities, and further liver histological observation. The inflammatory response was assessed by detecting liver myeloperoxidase (MPO) activity, and serum levels of tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and interferon-γ (IFN-γ). Western-blot analysis was used to detect the protein expression. The oxidative liver injury was evaluated by detecting liver malondialdehyde (MDA) and glutathione (GSH) contents, and glutathione peroxidase (GPx) enzymatic activity. In vivo anti-tumor activity was analyzed in S180 tumor-bearing mice.

RESULTS

SC significantly decreased the increased serum ALT/AST, and ALP activities induced by DB. Liver histological observation evidenced the protection of SC against DB-induced liver injury. SC obviously reduced the increased liver MPO activity and the number of MPO-positive staining cells induced by DB. SC also reversed the decreased expression of inhibitor of κB (IκB) and the translocation of nuclear factor κB (NF-κB) p65 from cytoplasm to nucleus induced by DB. In addition, SC significantly abrogated the increased serum levels of TNF-α, IL-6, and IFN-γ induced by DB. SC decreased the increased liver MDA content induced by DB significantly, and it also increased liver GSH level. The decreased GPx protein expression and its enzymatic activity induced by DB were both obviously reversed after SC treatment. The results in S180 tumor-bearing mice showed that SC combined with DB significantly inhibited tumor growth in vivo.

CONCLUSIONS

Our results demonstrate that SC prevents DB-induced liver injury by attenuating NF-κB-mediated hepatic inflammation and ameliorating liver oxidative stress injury. Meanwhile, DB plus SC has significant anti-tumor activity in vivo. This study indicates the potential combination of DB with SC for the treatment of cancer in clinic.

Biological evaluation and molecular docking of baicalin and scutellarin as Helicobacter pylori urease inhibitors

ETHNOPHARMACOLOGICAL RELEVANCE

Baicalin and scutellarin are the principal bioactive components of Scutellaria baicalensis Georgi which has extensively been incorporated into heat-clearing and detoxification formulas for the treatment of Helicobacter pylori-related gastrointestinal disorders in traditional Chinese medicine. However, the mechanism of action remained to be defined.

AIM OF THE STUDY

To explore the inhibitory effect, kinetics and mechanism of Helicobacter pylori urease (the vital pathogenetic factor for Helicobacter pylori infection) inhibition by baicalin and scutellarin, for their therapeutic potential.

MATERIALS AND METHODS

The ammonia formations, indicator of urease activity, were examined using modified spectrophotometric Berthelot (phenol-hypochlorite) method. The inhibitory effect of baicalin and scutellarin was characterized with IC50 values, compared to acetohydroxamic acid (AHA), a well known Helicobacter pylori urease inhibitor. Lineweaver-Burk and Dixon plots for the Helicobacter pylori urease inhibition of baicalin and scutellarin was constructed from the kinetic data. SH-blocking reagents and competitive active site Ni(2+) binding inhibitors were employed for mechanism study. Molecular docking technique was used to provide some information on binding conformations as well as confirm the inhibition mode. Moreover, cytotoxicity experiment using Gastric Epithelial Cells (GES-1) was evaluated.

RESULTS

Baicalin and scutellarin effectively suppressed Helicobacter pylori urease in dose-dependent and time-independent manner with IC50 of 0.82±0.07 mM and 0.47±0.04 mM, respectively, compared to AHA (IC50=0.14±0.05 mM). Structure-activity relationship disclosed 4'-hydroxyl gave flavones an advantage to binding with Helicobacter pylori urease. Kinetic analysis revealed that the types of inhibition were non-competitive and reversible with inhibition constant Ki of 0.14±0.01 mM and 0.18±0.02 mM for baicalin and scutellarin, respectively. The mechanism of urease inhibition was considered to be blockage of the SH groups of Helicobacter pylori urease, since thiol reagents (L,D-dithiothreitol, L-cysteine and glutathione) abolished the inhibitory action and competitive active site Ni(2+) binding inhibitors (boric acid and sodium fluoride) carried invalid effect. Molecular docking study further supported the structure-activity analysis and indicated that baicalin and scutellarin interacted with the key residues Cys321 located on the mobile flap through S-H·π interaction, but did not interact with active site Ni(2+). Moreover, Baicalin (at 0.59-1.05 mM concentrations) and scutellarin (at 0.23-0.71 mM concentrations) did not exhibit significant cytotoxicity to GES-1.

CONCLUSIONS

Baicalin and scutellarin were non-competitive inhibitors targeting sulfhydryl groups especially Cys321 around the active site of Helicobacter pylori urease, representing potential to be good candidate for future research as urease inhibitor for treatment of Helicobacter pylori infection. Furthermore, our work gave additional scientific support to the use of Scutellaria baicalensis in traditional Chinese medicine (TCM) to treat gastrointestinal disorders.

In vitro effects of some flavones on human pyruvate kinase isoenzyme M2

PKM2 is an important target for designing anticancer drug. Inhibitors and activators of this enzyme are suitable molecules for use in treating cancer. The aim of the present study was to investigate the effect of certain flavones on PKM2. Apigenin, wogonin, flavone, 3-hydroxyflavone, 5-hydroxyflavone, 6-hydroxyflavone, and 7-hydroxyflavone effectively inhibited PKM2, with IC50 in the range of 0.99-2.120 μM. The kinetic study indicated that these compounds acted as noncompetitive with Ki values of 3.53-5.67 μM toward phosphoenolpyruvate. Scutellarin and tangeritin demonstrated strong activation effect with AC50 values < 2 μM. Diosmetin, baicalin, baicalein, and luteolin showed an intermediate-level activator effect. These results demonstrate that flavone and their analogs could serve as leading compounds to develop new potent and selective inhibitor and activator for PKM2.

Xylooligosaccharides: an economical prebiotic from agroresidues and their health benefits

Oligosaccharides and dietary fibres are non-digestible food ingredients that preferentially stimulate the growth of prebiotic Bifidobacterium and other lactic acid bacteria in the gastro-intestinal tract. Xylooligosaccharides (XOS) provide a plethora of health benefits and can be incorporated into several functional foods. In the recent times, there has been an over emphasis on the microbial conversion of agroresidues into various value added products. Xylan, the major hemicellulosic component of lignocellulosic materials (LCMs), represents an important structural component of plant biomass in agricultural residues and could be a potent bioresource for XOS. On an industrial scale, XOS can be produced by chemical, enzymatic or chemo-enzymatic hydrolysis of LCMs. Chemical methods generate XOS with a broad degree of polymerization (DP), while enzymatic processes will be beneficial for the manufacture of food grade and pharmaceutically important XOS. Xylooligomers exert several health benefits, and therefore, have been considered to provide relief from several ailments. This review provides a brief on production, purification and structural characterization of XOS and their health benefits.

The thermic effect of sugar-free Red Bull: do the non-caffeine bioactive ingredients in energy drinks play a role?

OBJECTIVE

Consumption of energy drinks is increasing amongst athletes and the general public. By virtue of their bioactive ingredients (including caffeine, taurine, glucuronolactone, and B-group vitamins) and paucity of calories, sugar-free "diet" versions of these drinks could be a useful aid for weight maintenance. Yet little is known about the acute influence of these drinks, and specifically the role of the cocktail of non-caffeine ingredients, on resting energy expenditure (REE) and substrate oxidation. Therefore, the metabolic impact of sugar-free Red Bull (sfRB) to a comparable amount of caffeine was compared.

METHODS

REE and respiratory quotient (RQ) were measured in eight healthy young men by ventilated-hood indirect calorimetry for 30 min baseline and 2 h following ingestion of 355 ml of either: sfRB + placebo, water + 120 mg caffeine, or water + placebo, according to a randomized cross-over design.

RESULTS

sfRB and water + caffeine both increased REE to the same degree (+4%). Additionally, sfRB briefly increased RQ. Water + caffeine had no effect on RQ relative to water + placebo.

CONCLUSIONS

sfRB enhanced thermogenesis and marginally shifted RQ to favor carbohydrate oxidation. The stimulatory effects of sfRB on REE are mimicked by water + caffeine, indicating that the auxiliary ingredients do not influence this thermic effect. The metabolic effects of sfRB are primarily due to caffeine alone.

The effects of dietary xylooligosaccharide on mucosal parameters, intestinal microbiota and morphology and growth performance of Caspian white fish (Rutilus frisii kutum) fry

The present study investigates the effects of different levels of dietary xylooligosaccharide (XOS) on skin mucus bactericidal activity and protein content, intestinal microbiota and morphology as well as growth performance of Caspian white fish (Rutilus frisii kutum) fry. The specimens (1.54 ± 0.03 g) were fed experimental diets supplemented with different levels of XOS [0% (control), 1%, 2% and 3%] for 8 weeks. The results revealed that feeding on XOS significantly increased skin mucus antibacterial activity and protein levels (P < 0.05) and the highest levels were observed in 3% XOS treatment. The total autochthonous intestinal heterotrophic bacteria significantly increased following XOS administration in diet (P < 0.05). Administration of 2 or 3% XOS in fry diet significantly elevated the autochthonous lactic acid bacteria (P < 0.05). However, dietary XOS had no significant effect on intestinal morphology, growth performance and diet utilisation of Caspian white fish fry (P > 0.05). These results demonstrate beneficial effects of dietary XOS on different parameters of mucosal immunity (both skin mucus and intestinal microbiota) and encourage further studies regards various aspect of XOS administration in early life stages of fish.

In vivo effects of scutellarin on the activities of CYP1A2, CYP2C11, CYP2D1, and CYP3A1/2 by cocktail probe drugs in rats

OBJECTIVE

To investigate the influence of scutellarin on the activities of CYP1A2, CYP2C11, CYP2D1, and CYP3A1/2 in rats in vivo.

METHODS

Scutellarin and saline were intravenously administered to male Wistar rats via the caudal vein for 7 days consecutively. On the 8th day, the rats were treated with probe drugs of caffeine (10 mg/kg), tolbutamide (10 mg/kg), metoprolol (20 mg/kg), dapsone (10 mg/kg) by intraperitoneal injection, and the blood samples were collected at different times. The probe drugs in the blood samples were measured by ultra performance liquid chromatography mass spectrometer (UPLC-MS/MS) and the changes of the pharmacokinetics parameters of the drugs were observed to evaluate the effects of scutellarin on the four CYP450 isoforms in rats.

RESULTS

The activity of CYP1A2 in rats was inhibited significantly after treatment with scutellarin by increased caffeine t1/2 (21.76%, P < 0.05), T(max) (43.05%, P < 0.05), C(max) (43.92%, P < 0.01) and AUC(0-infinity) (50.88%, P < 0.01) in the scutellarin-treated group compared with those of the blank control. The activity of CYP2C11 in rats was inhibited significantly after treatment with scutellarin by increased tolbutamide t1/2 (16.74%, P < 0.01), T(max) (116.87%, P < 0.05), C(max) (63.78%, P < 0.01) and AUC(0-infinity) (70.61%, P < 0.01) in the scutellarin-treated group compared with those of the blank control. The activity of CYP3A1/2 in rats was inhibited significantly after treatment with scutellarin by increased dapsone t1/2 (45.28%, P < 0.05), T(max) (81.55%, P < 0.05), C(max) (155.58%, P < 0.01)and AUC(0-infinity) (176.35%, P < 0.01) in the scutellarin-treated group compared with those of the blank control. The pharmacokinetic parameters of metoprolol were not significantly changed in the scutellarin-treated group compared with those of the blank control.

CONCLUSION

Scutellarin could significantly inhibit CYP1A2, CYP2C11 and CYP3A1/2 activities in rats in vivo, but had no effects on the activity of CYP2D1.

Scutellarin and caffeic acid ester fraction, active components of Dengzhanxixin injection, upregulate neurotrophins synthesis and release in hypoxia/reoxygenation rat astrocytes

ETHNOPHARMACOLOGICAL RELEVANCE

Scutellarin (Scu) and caffeic acid ester fraction (Caf), the extracts from the traditional Chinese herb, Erigeron breviscapus, are known to ameliorate post ischemic neuronal dysfunction.

AIM OF THE STUDY

Neurotrophic factors (NTFs) are essential for neuronal growth and survival. We explored the neuroprotective effect of Scu and Caf by synthesis and release of NGF, BDNF and GDNF in rat astrocytes exposed to hypoxia/reoxygenation and MACO rats. And the neuroprotection of Scu and Caf was also explored.

MATERIALS AND METHODS

The primary rat astrocytes were cultured in vitro. The temporal mRNA and protein expression profile during hypoxia/reoxygenation were analyzed using real-time RT-PCR and ELISA. The expression of p-CREB, p-Akt, p-MAPKs and Bax were analyzed by western blotting. Cell viability of neuro-2A was measured using CCK-8 and cell cytotoxicity was measured with LDH release.

RESULTS

During hypoxia/reoxygenation a similar decrease pattern of NTFs (NGF, BDNF and GDNF) was observed in both mRNA and protein; Scu and Caf enhanced the expressions of NGF, BDNF and GDNF mRNA and protein in astrocytes under hypoxia/reoxygenation condition. CREB and Akt, but not MAPKs ( p-JNK, p-ERK1/2 and p-38) may be involved in the expression of NTFs. Concomitantly, conditioned medium from astrocytes which was treated by Scu or Caf after hypo3h/Reox24h significantly reduced neurotoxicity compared with conditioned medium from hypo3h/Reox24h astrocytes alone, and they show the tendency of increased neurons viability accompanied with Bax changes.

CONCLUSIONS

These results indicate that the neuroprotective effect of Scu and Caf might be mediated, at least in part, via a stimulation of the production and release of NTFs through p-CREB and p-Akt signaling. Furthermore, Scu and Caf could antagonistic the hypoxia induced toxicity through astrocytes conditioned medium. Those results suggested that Scu and Caf might have therapeutic potential for stroke.

Scutellarin attenuates hypertension-induced expression of brain Toll-like receptor 4/nuclear factor kappa B

Hypertension is associated with low-grade inflammation, and Toll-like receptor 4 (TLR4) has been shown to be linked to the development and maintenance of hypertension. This study aimed to investigate the effects of scutellarin (administered by oral gavage daily for 2 weeks) on brain TLR4/nuclear factor kappa B-(NF- κ B-) mediated inflammation and blood pressure in renovascular hypertensive (using the 2-kidney, 2-clip method) rats. Immunofluorescence and western immunoblot analyses revealed that hypertension contributed to the activation of TLR4 and NF- κ B, accompanied by significantly enhanced expression of proinflammatory mediators, such as tumor necrosis factor- α (TNF- α ), interleukin-1 β (IL-1 β ), and interleukin-18 (IL-18). Furthermore, expression of the antiapoptotic protein, myeloid cell leukemia-1 (Mcl1), was decreased, and the pro-apoptotic proteins, Bax and cleavedcaspase-3 p17 were increased in combined cerebral cortical/striatal soluble lysates. Scutellarin significantly lowered blood pressure and attenuated the number of activated microglia and macrophages in brains of hypertensive rats. Furthermore, scutellarin significantly reduced the expression of TLR4, NF- κ B p65, TNF- α , IL-1 β , IL-18, Bax and cleaved-caspase-3 p17, and increased the expression of Mcl1. Overall, these results revealed that scutellarin exhibits anti-inflammatory and anti-apoptotic properties and decreases blood pressure in hypertensive rats. Therefore, scutellarin may be a potential therapeutic agent in hypertension-associated diseases.

Scutellarin from Scutellaria baicalensis suppresses adipogenesis by upregulating PPARα in 3T3-L1 cells

Adipocyte dysfunction is a major cause of obesity, which is associated strongly with many disorders including psychological and medical morbidities, metabolic abnormalities, and cardiovascular diseases as well as a series of cancers. This study investigated the antiadipogenic activity of scutellarin (1) in 3T3-L1 preadipocytes as well as the underlying molecular mechanisms. It was observed that 1 reduced adipocyte differentiation of 3T3-L1 cells potently, as evidenced by a decrease in cellular lipid accumulation. At the molecular level, mRNA expression of the master adipogenic transcription factors, PPARγ and C/EBPα, was decreased markedly. However, mRNA levels of C/EBPβ, the upstream regulator of PPARγ and C/EBPα, were not decreased by 1. Moreover, a dose-dependent upregulation of PPARα was observed for 1. Computational modeling indicated that 1 can bind to PPARα, γ, and δ each in a distinct manner, while it can activate PPARα only by forming a hydrogen bond with Y464, thus stabilizing the AF-2 helix and activating PPARα. Therefore, these results suggest that 1, a major component of Scutellaria baicalensis, attenuates fat cell differentiation by upregulating PPARα as well as downregulating the expression of PPARγ and C/EBPα, thus showing therapeutic potential for obesity-related diseases.

Effect of a straw-derived xylooligosaccharide on broiler growth performance, endocrine metabolism, and immune response

The aim of this work was to evaluate the effect of 3 levels of supplemental xylooligosaccharides (XOS) from straw on the growth performance, endocrine metabolism, and immune response of broiler chickens. Day-old, healthy Arbor Acres broilers (n = 192) received a basal diet of maize-soybean meal and, depending on the group to which they were allocated, no additive (control group) or the following experimental treatments for 59 d: treatment 1: 5 g XOS/kg; treatment 2: 10 g XOS/kg; and treatment 3: 20 g XOS/kg. By day 59 the body weight gain of the chickens receiving treatment 2 had increased by 9.44% (P < 0.01) over the gain of the control group. The levels of serum triiodothyronine, thyroxine, and insulin on day 44 were significantly higher in the treatment groups than in the control group. The titers of antibody to the avian influenza H5N1 virus on day 24 were also significantly higher in the treatment groups than in the control group, and on day 59 the titer of the chickens receiving treatment 2 were still significantly increased (P < 0.05). Thus, the addition of XOS to feed can increase growth performance, enhance endocrine metabolism, and improve immune function in broiler chickens.

Potentiation of scutellarin on human tongue carcinoma xenograft by low-intensity ultrasound

Scutellarin 7-O-β-d-glucuronide (scutellarin) has shown great potential as a chemotherapeutic agent for cancer treatment, but only at high dosage. Here we investigate the possibility of using low intensity ultrasound to reduce the scutellarin dosage. Ultrasound intensities of 1.0 W/cm² and 0.05 W/cm² were used for in vivo and in vitro experiments, respectively, and a very low dosage of scutellarin (15 nM) was used. Tumor-bearing Balb/c mice and SAS human-tongue squamous carcinoma cell suspensions were used for the in vivo and in vitro experiments, respectively. Each kind of subjects was divided into control, ultrasound-alone, scutellarin-alone, and combined ultrasound-scutellarin treatment groups. Only the combined treatment showed strong anticancer effects. In the in vivo case, the combined treatment significantly delayed tumor growth, initiated cellular chromatin changes (including a decrease in the number of cytoplasmic organelles and fragmentation of condensed nuclear chromatin), inhibited tumor angiogenesis and lymphangiogenesis, stopped cancer-cell proliferation, decreased MMP-2 and MMP-9 expression levels and caused cancer-cell apoptosis. In the in vitro case, the combined treatment produced cancer cell-shape irregularity in a manner seriously fractured microvilli, inhibited cancer-cell migratory and invasion activities, and induced cancer-cell apoptosis. Because the combined treatment did not increase intracellular ROS production, scutellarin is not a sonosensitizer so that the anticancer effect is not through sonodynamic therapy. Low-intensity ultrasound is merely increasing the permeability of scutellarin into cancer cells. Based on our results, one may perform localized chemotherapy using much reduced dosage of the drug with the help of low intensity ultrasound, which will greatly minimize side effects.