Scutellarin alleviates renal ischemia-reperfusion injury by inhibiting the MAPK pathway and pro-inflammatory macrophage polarization.

Renal ischemia-reperfusion injury (IRI) is an integral process in renal transplantation, which results in compromised graft survival. Macrophages play an important role in both the early inflammatory period and late fibrotic period in response to IRI. In this study, we investigated whether scutellarin (SCU) could protect against renal IRI by regulating macrophage polarization. Mice were given SCU (5-50 mg/kg) by gavage 1 h earlier, followed by a unilateral renal IRI. Renal function and pathological injury were assessed 24 h after reperfusion. The results showed that administration of 50 mg/kg SCU significantly improved renal function and renal pathology in IRI mice. In addition, SCU alleviated IRI-induced apoptosis. Meanwhile, it reduced macrophage infiltration and inhibited pro-inflammatory macrophage polarization. Moreover, in RAW 264.7 cells and primary bone marrow-derived macrophages (BMDMs) exposed to SCU, we found that 150 µM SCU inhibited these cells to polarize to an inflammatory phenotype induced by lipopolysaccharide (LPS) and interferon-γ (IFN-γ). However, SCU has no influence on anti-inflammatory macrophage polarization in vivo and in vitro induced by in interleukin-4 (IL-4). Finally, we explored the effect of SCU on the activation of the mitogen-activated protein kinase (MAPK) pathway both in vivo and in vitro. We found that SCU suppressed the activation of the MAPK pathway, including the extracellular signal-regulated kinase (ERK), Jun N-terminal kinase (JNK), and p38. Our results demonstrated that SCU protects the kidney against IRI by inhibiting macrophage infiltration and polarization toward pro-inflammatory phenotype via the MAPK pathway, suggesting that SCU may be therapeutically important in treatment of IRI.

Optimization of the Preparation Process of Glucuronomannan Oligosaccharides and Their Effects on the Gut Microbiota in MPTP-Induced PD Model Mice.

Parkinson's disease (PD) is a prevalent neurodegenerative disorder, and accumulating evidence suggests a link between dysbiosis of the gut microbiota and the onset and progression of PD. In our previous investigations, we discovered that intraperitoneal administration of glucuronomannan oligosaccharides (GMn) derived from Saccharina japonica exhibited neuroprotective effects in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model. However, the complicated preparation process, difficulties in isolation, and remarkably low yield have constrained further exploration of GMn. In this study, we optimized the degradation conditions in the preparation process of GMn through orthogonal experiments. Subsequently, an MPTP-induced PD model was established, followed by oral administration of GMn. Through a stepwise optimization, we successfully increased the yield of GMn, separated from crude fucoidan, from 1~2/10,000 to 4~8/1000 and indicated the effects on the amelioration of MPTP-induced motor deficits, preservation of dopamine neurons, and elevation in striatal neurotransmitter levels. Importantly, GMn mitigated gut microbiota dysbiosis induced by MPTP in mice. In particular, GM2 significantly reduced the levels of Akkermansia, Verrucomicrobiota, and Lactobacillus, while promoting the abundance of Roseburia and Prevotella compared to the model group. These findings suggest that GM2 can potentially suppress PD by modulating the gut microbiota, providing a foundation for the development of a novel and effective anti-PD marine drug.

Identifying Anti-NSCLC Bioactive Compounds in Scutellaria via 2D NMR-Based Metabolomic Analysis of Pharmacologically Classified Crude Extracts.

We presented a strategy utilizing 2D NMR-based metabolomic analysis of crude extracts, categorized by different pharmacological activities, to rapidly identify the primary bioactive components of TCM. It was applied to identify the potential bioactive components from Scutellaria crude extracts that exhibit anti-non-small cell lung cancer (anti-NSCLC) activity. Four Scutellaria species were chosen as the study subjects because of their close phylogenetic relationship, but their crude extracts exhibit significantly different anti-NSCLC activity. Cell proliferation assay was used to assess the anti-NSCLC activity of four species of Scutellaria. 1H-13C HSQC spectra were acquired for the chemical profiling of these crude extracts. Based on the pharmacological classification (PCA, OPLS-DA and univariate hypothesis test) were performed to identify the bioactive constituents in Scutellaria associated with the anti-NSCLC activity. As a result, three compounds, baicalein, wogonin and scutellarin were identified as bioactive compounds. The anti-NSCLC activity of the three potential active compounds were further confirmed via cell proliferation assay. The mechanism of the anti-NSCLC activity by these active constituents was further explored via flow cytometry and western blot analyses. This study demonstrated 2D NMR-based metabolomic analysis of pharmacologically classified crude extracts to be an efficient approach to the identification of active components of herbal medicine.

Are phenolic compounds produced during the enzymatic production of prebiotic xylooligosaccharides (XOS) beneficial: a review.

Phenolics produced during xylooligosaccharide production might inhibit xylanases and enhance the antioxidant and antimicrobial activities of XOS. The effects of phenolic compounds on xylanases may depend on the type and concentration of the compound, the plant biomass used, and the enzyme used. Understanding the effects of phenolic compounds on xylanases and their impact on XOS is critical for developing viable bioconversion of lignocellulosic biomass to XOS. Understanding the complex relationship between phenolic compounds and xylanases can lead to the development of strategies that improve the efficiency and cost-effectiveness of XOS manufacturing processes and optimise enzyme performance.

Modulation of the Cardiovascular Risk in Type 1 Diabetic Rats by Endurance Training in Combination with the Prebiotic Xylooligosaccharide.

Diabetic cardiomyopathy is a major etiological factor in heart failure in diabetic patients, characterized by mitochondrial oxidative metabolism dysfunction, myocardial fibrosis, and marked glycogen elevation. The aim of the present study is to evaluate the effect of endurance training and prebiotic xylooligosaccharide (XOS) on the activity of key oxidative enzymes, myocardial collagen, and glycogen distribution as well as some serum biochemical risk markers in streptozotocin-induced type 1 diabetic rats. Male Wistar rats (n = 36) were divided into four diabetic groups (n = 9): sedentary diabetic rats on a normal diet (SDN), trained diabetic rats on a normal diet (TDN), trained diabetic rats on a normal diet with an XOS supplement (TD-XOS), and sedentary diabetic rats with an XOS supplement (SD-XOS). The results show that aerobic training managed to increase the enzyme activity of respiratory Complex I and II and the lactate dehydrogenase in the cardiomyocytes of the diabetic rats. Furthermore, the combination of exercise and XOS significantly decreased the collagen and glycogen content. No significant effects on blood pressure, heart rate or markers of inflammation were detected. These results demonstrate the beneficial effects of exercise, alone or in combination with XOS, on the cardiac mitochondrial enzymology and histopathology of diabetic rats.

Xylooligosaccharide supplementation in rice protein concentrate based diets: A comprehensive analysis of performance and health of Labeo rohita.

The primary aim of this study was to examine the impact of xylooligosaccharide (XOS) in rice protein concentrate (RPC) based diets on the growth performance, body composition, digestive enzymes, intestinal morphology and blood biochemistry of Labeo rohita fingerlings. Four different XOS levels (0%, 0.5%, 1% and 2%) were used at each RPC (75% and 100%) level. Twenty-five fish per tank with an average initial weight of 25 ± 0.05 g were randomly assigned (Randomised complete block design) to each of the 8 groups in triplicate aquaria (36 × 16 × 12″) and then fed with respective diets @ 3% body weight for 90 days. The results showed significant improvements in growth performance, such as increased weight gain %, specific growth rate, and protein efficiency ratio and improved feed conversion ratio in 1% XOS supplemented diet at 75% RPC. A significant decrease in serum alkaline phosphatase activity (ALP) and plasma melanodialdehyde (MDA) were observed at 1% XOS level in 75% RPC based diets, respectively. Meanwhile, the lowest total cholesterol and highest lysozyme activity were observed in 1% XOS supplemented diet at 75% RPC levels. Moreover, the serum (alanine aminotransferase and aspartate transaminase) and plasma (superoxide dismutase, triglyceride, high density and low density lipoprotein) activities showed nonsignificant effects among the treatments. Furthermore, the digestive enzymes (protease & lipase) and intestinal morphology were significantly influenced at 1% XOS in the 75% RPC-based diet. Polynomial regression analysis showed that 1.25% XOS is the optimum requirement for the growth of rohu fingerlings when fed at 75% RPC based diets. Overall, it was concluded that the 75% RPC diet was efficiently replaced by fishmeal along with 1% XOS addition in L. rohita fingerlings without any negative effect on growth performance and intestinal health.

Protective Effects of Scutellarin on Acute Alcohol Intestinal Injury.

The present study aims to investigate the roles of scutellarin (SCU) on acute alcohol intestinal injury. Mice were divided into six groups: alcohol, three administration, negative control and positive drug bifendate control. The administration group mice were intraperitoneally injected with SCU for 3 consecutive days followed by alcohol gavage at an interval of 1 h. After the mice were sacrificed, colon tissue damage was evaluated by histopathological examination; the activities of inducible nitric oxide synthase (iNOS) and catalase (CAT), as well as the content of malondialdehyde (MDA) were detected using biochemical kits; the levels of inflammatory cytokines mRNA were determined by real-time fluorescence quantitative PCR; the protein expression levels of hemeoxygenase-1 (HO-1) and phosphorylated nuclear factor-ĸB p65 were measured via western blotting. The results showed that alcohol induced severe colon morphological degradation, epithelia atrophy, and more inflammatory cells infiltration in the submucosa. SCU treatment prevented this process, especially in the middle and high dose groups. Alcohol treatment caused excessive lipid peroxidation product accumulation of MDA, restrained the activity of antioxidant enzyme CAT, induced HO-1 expression in the colon, whereas low dose SCU treatment significantly down-regulated the MDA level, enhanced the CAT level, and accelerated HO-1 signals. SCU prevented alcohol stimulation triggered inflammatory response in colon tissues through significantly downregulating the iNOS activity, transcript levels of Tnf-α, Il-1ß and Il-6, and phosphorylation levels of NF-κB p65. These findings suggest that SCU protects the colon via antioxidant and anti-inflammatory mechanisms, making it a promising drug against alcohol-induced colon damage.

EGR1 promoted anticancer effects of Scutellarin via regulating LINC00857/miR-150-5p/c-Myc in osteosarcoma.

Scutellarin, an active flavone extracted from Erigeron breviscapus, is known to exhibit antitumour activity in many cancers. However, the effects of Scutellarin on osteosarcoma remain unclear. In this study, we found that Scutellarin suppressed osteosarcoma cell growth, induced cell apoptosis and inhibited tumorigenesis. Mechanistically, our data revealed that EGR1 was significantly increased under Scutellarin treatment. Increased EGR1 enhanced tumour-suppressive effects of Scutellarin on osteosarcoma cells via transcriptionally downregulating LINC00857 expression. Additionally, we found that LINC00857 acted as a competitive endogenous RNA of miR-150-5p and inhibited the activity of miR-150-5p, which resulted in c-Myc increase. Scutellarin could suppress c-Myc protein levels through decreasing LINC00857 expression in osteosarcoma. Thus, these findings demonstrate that EGR1/ LINC00857/miR-150-5p/c-Myc axis plays a key role in promoting anticancer effects of Scutellarin and Scutellarin might have potential clinical implication in osteosarcoma clinical treatment.

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.

Scutellarin inhibits the uninduced and metal-induced aggregation of α-Synuclein and disaggregates preformed fibrils: implications for Parkinson's disease.

The aggregation of the protein alpha synuclein (α-Syn), a known contributor in Parkinson's disease (PD) pathogenesis is triggered by transition metal ions through occupational exposure and disrupted metal ion homeostasis. Naturally occurring small molecules such as polyphenols have emerged as promising inhibitors of α-Syn fibrillation and toxicity and could be potential therapeutic agents against PD. Here, using an array of biophysical tools combined with cellular assays, we demonstrate that the novel polyphenolic compound scutellarin efficiently inhibits the uninduced and metal-induced fibrillation of α-Syn by acting at the nucleation stage and stabilizes a partially folded intermediate of α-Syn to form SDS-resistant, higher-order oligomers (∼680 kDa) and also disaggregates preformed fibrils of α-Syn into similar type of higher-order oligomers. ANS binding assay, fluorescence lifetime measurements and cell-toxicity experiments reveal scutellarin-generated oligomers as compact, low hydrophobicity structures with modulated surface properties and significantly reduced cytotoxicity than the fibrillation intermediates of α-Syn control. Fluorescence spectroscopy and isothermal titration calorimetry establish the binding between scutellarin and α-Syn to be non-covalent in nature and of moderate affinity (Ka ∼ 105 M-1). Molecular docking approaches suggest binding of scutellarin to the residues present in the NAC region and C-terminus of monomeric α-Syn and the C-terminal residues of fibrillar α-Syn, demonstrating inhibition of fibrillation upon binding to these residues and possible stabilization of the autoinhibitory conformation of α-Syn. These findings reveal interesting insights into the mechanism of scutellarin action and establish it as an efficient modulator of uninduced as well as metal-induced α-Syn fibrillation and toxicity.

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 ameliorates the stress-induced anxiety-like behaviors in mice by regulating neurotransmitters.

Anxiety disorders are a common frequently psychiatric symptom in patients that lead to disruption of daily life. Scutellarin (Scu) is the main component of Erigeron breviscapus, which has been used as a neuroprotective agent against glutamate-induced excitotoxicity. However, the potential effect of Scu on the stress-related neuropsychological disorders has not been clarified. In this study, Anxiety-like behavior was induced by acute restraint stress in mice. Scu were injected intraperitoneally (twice daily, 3 days). Results showed that Scu exhibited good protective activity on mice by decreasing transmitter release levels. Restraint stress caused significant anxiety like behavior in mice. Treatment of Scu could significantly improve the moving time of open arms in Elevated Plus Maze and central time on open field test. Scu treatment suppressed action potential firing frequency, restored excessive presynaptic quantal release, and down-regulated glutamatergic receptor expression levels in the prefrontal cortex (PFC) of stressed mice. GABAA Rα1 and GABAA γ2 expression in the brain PFC tissues of mice were nearly abrogated by Scu treatment. In stress-induced anxiety mice, stress can increase the frequency of mini excitatory postsynaptic currents (mEPSC), which can be reversed by Scu treatment. Therefore, Scu has a potent anxiolytic activity and may be valuable for the treatment of stress-induced anxiety disorders.

Effectiveness of Scutellaria barbata water extract on inhibiting colon tumor growth and metastasis in tumor-bearing mice.

The plant Scutellaria barbata (SB) is commonly used as herbal medicines for treating cancer. The present pre-clinical study aimed to validate the Chinese Pharmacopoeia (CP) recommended dosages of SB water extract (SBW) in treating colon tumors. The content of chemical marker scutellarin in SBW was quantified using UPLC. Mice bearing human HCT116 xenografts or murine colon26 tumors received oral administration of SBW or scutellarin for 4 weeks. Results showed that SBW (615 and 1,230 mg/kg) and scutellarin (7 mg/kg) treatments significantly reduced human xenograft weights by 28.7, 36.9 and 28.8%, respectively. Lung metastasis area could be ameliorated after SBW (615 mg/kg) and scutellarin (7 mg/kg) treatments by 23.4 and 29.5%, respectively. Expressions of colon cancer metastasis-related proteins E-cadherin, Tspan 8 and CXCR4, as well as Src kinase in tumors were first shown to be regulated by SBW. Furthermore, in murine colon26 tumor-bearing mice, SBW (615 mg/kg) and scutellarin (7 mg/kg) treatments reduced the orthotopic tumor burden by 94.7% and lung metastatic tumor burden by 94.1%, respectively. Our findings provided evidences that SBW (at the mouse equivalent dosages to clinical dosages recommended by CP) could exert anti-tumor and anti-metastatic effects in colon cancer animal models.

4,5 caffeoylquinic acid and scutellarin, identified by integrated metabolomics and proteomics approach as the active ingredients of Dengzhan Shengmai, act against chronic cerebral hypoperfusion by regulating glutamatergic and GABAergic synapses.

Dengzhan Shengmai (DZSM) is a proprietary Chinese medicine for remarkable curative effect as a treatment of cerebrovascular diseases, such as chronic cerebral hypoperfusion (CCH) and dementia based on evidence-based medicine, which have been widely used in the recovery period of ischemic cerebrovascular diseases. The purpose of this study was to investigate the active substances and mechanism of DZSM against CCH. Integrative metabolomic and proteomic studies were performed to investigate the neuroprotective effect of DZSM based on CCH model rats. The exposed components of DZSM in target brain tissue were analysed by a high-sensitivity HPLC-MS/MS method, and the exposed components were tested on a glutamate-induced neuronal excitatory damage cell model for the verification of active ingredients and mechanism of DZSM. Upon proteomic and metabolomic analysis, we observed a significant response in DZSM therapy from the interconnected neurotransmitter transport pathways including glutamatergic and GABAergic synapses. Additionally, DZSM had a significant regulatory effect on glutamate and GABA-related proteins including vGluT1 and vIAAT, suggested that DZSM could be involved in the vesicle transport of excitatory and inhibitory neurotransmitters in the pre-synaptic membrane. DZSM could also regulated the metabolism of arachidonic acid (AA), phospholipids, lysophospholipids and the expression of phospholipase A2 in post-synaptic membrane. The results of glutamate-induced neuronal excitatory injury cell model experiment for verification of active ingredients and mechanism of DZSM showed that there are five active ingredients, and among them, 4,5 caffeoylquinic acid (4,5-CQA) and scutellarin (SG) could simultaneously affect the GABAergic and glutamatergic synaptic metabolism as well as the related receptors, the NR2b subunit of NMDA and the α1 subunit of GABAA. The active ingredients of DZSM could regulate the over-expression of the NMDA receptor, enhance the expression of the GABAA receptor, resist glutamate-induced neuronal excitatory damage, and finally maintain the balance of excitatory and inhibitory synaptic metabolism dominated by glutamate and GABA. Furtherly, we compared the efficacy of DZSM, 4,5-CQA, SG and the synergistic effect of 4,5-CQA and SG, and the results showed that all the groups significantly improved cell viability compared with the model group (p < 0.001). The western blot results showed that DZSM, 4,5-CQA, SG and 4,5-CQA/SG co-administration groups could significantly regulate the expression of receptors (GABAA α1 and NR2b subunit of NMDA) and synaptic-related proteins, such as Sv2a, Syp, Slc17a7, bin1 and Prkca, respectively. These results proved DZSM and its active ingredients (4,5-CQA and SG) had the effect of regulating glutamatergic and GABAergic synapses. Finally, membrane potential FLIPR assay of 4,5-CQA and SG was used for GABRA1 activity test, and it was found that the two compounds could increase GABA-induced activation of GABRA1 receptor (GABA 10 µM) in a dose-dependent manner with EC50 value of 48.74 µM and 29.77 µM, respectively. Manual patch clamp method was used to record NMDA NR1/NR2B subtype currents, and scutellarin could cause around 10 % blockade at 10 µM (p＜0.05 compared with the control group). These studies provided definitive clues of the mechanism for the neuroprotective effect of DZSM for CCH treatment and the active compounds regulating glutamatergic and GABAergic synapses. Additionally, 4,5-CQA and SG might be potential drugs for the treatment of neurodegenerative disease related to CCH.

Scutellarin is Highly Likely to be Responsible for Drug-Drug Interactions Mediated by Hepatic Organic Anion-Transporting Polypeptide1B3.

PURPOSE: Scutellarin, a flavonoid derived from the plant Erigeron breviscapus, is currently widely used to treat cerebrovascular diseases, liver-related diseases, and hyperlipidemia in china and other East Asian countries. This study was to investigate the effect of scutellarin on the uptake of rosuvastatin in HEK293T cells expressing human organic anion transporting polypeptide 1B3 (hOATP1B3) and rat OATP1B2 (rOATP1B2), respectively, and the effect of scutellarin on the pharmacokinetics of rosuvastatin in rats. METHODS: The newly established HEK293T cells expressing hOATP1B3 and rOATP1B2 were used to examine the effects of scutellarin and positive controls on in vitro rosuvastatin transport. After co-feeding with scutellarin, the rosuvastatin area under the plasma concentration-time curve (AUC0-24h), the peak plasma drug concentration (Cmax), elimination half-life (t1/2), time to reach Cmax (tmax), clearance (CL) and apparent clearance (CL/F) of rosuvastatin were determined in rats. RESULTS: Scutellarin inhibited hOATP1B3- and rOATP1B2-mediated rosuvastatin uptake (IC50: 45.54 ± 6.67 µM and 27.58 ± 3.97 µM) in vitro in a concentration-dependent manner. After co-feeding with scutellarin, the AUC0-24h and Cmax of rosuvastatin in rats increased to 27.4% and 37.7%, respectively. The t1/2 and tmax of rosuvastatin showed no significant change. Moreover, scutellarin caused 29.2% and 28.1% decrease in the CL and CL/F of rosuvastatin. CONCLUSION: Scutellarin may inhibit the hOATP1B3- and rOATP1B2-mediated transport of rosuvastatin in vitro, and exerts a moderate inhibitory effect on the pharmacokinetics of rosuvastatin in rats. Scutellarin is highly likely to participate in drug-drug interactions, as mediated by OATP1B3 in humans.

Synthesis, pharmacological evaluation and mechanistic study of scutellarin methyl ester -4'-dipeptide conjugates for the treatment of hypoxic-ischemic encephalopathy (HIE) in rat pups.

A series of novel scutellarin methyl ester-4'-dipeptide conjugates exhibiting active transport characteristics and protection against pathological damage caused by hypoxic-ischemic encephalopathy (HIE) were successfully designed and synthesized. The physiochemical properties of the obtained compounds, as well as the Caco-2 cell-based permeability and uptake into hPepT1-MDCK cells were evaluated using various analytical methods. Scutellarin methyl ester-4'-Val-homo-Leu dipeptide (5k) was determined as the optimal candidate with a high apparent permeability coefficient (Papp A to B) of 1.95 ± 0.24 × 10-6 cm/s, low ER (Papp BL to AP/Papp AP to BL) of 0.52 in Caco-2 cells, and high uptake of 25.47 µmol/mg/min in hPepT1-MDCK cells. Comprehensive mechanistic studies demonstrated that pre-treatment of PC12 cells with 5k resulted in more potent anti-oxidative activity, which was manifested by a significant decrease in the malondialdehyde (MDA) and reactive oxygen species (ROS) levels, attenuation of the H2O2-induced apoptotic cell accumulation in the sub-G1 peak, and improvement in the expression of the relevant apoptotic proteins (Bcl-2, Bax, and cleave-caspase-3). Moreover, evaluation of in vivo neuroprotective characteristics in hypoxic-ischemic rat pups revealed that 5k significantly reduced infarction and alleviated the related pathomorphological damage. The compound was also shown to ameliorate the neurological deficit at 48 h as well as to decrease the brain tissue loss at 4 weeks. Conjugate 5k was demonstrated to reduce the amyloid precursor protein (APP) and ß-site APP-converting enzyme-1 (BACE-1) expression. Pharmacokinetic characterization of 5k indicated favorable druggability and pharmacokinetic properties. The conducted docking studies revealed optimal binding of 5k to PepT1. Hydrogen bonding as well as cation-π interactions with the corresponding amino acid residues in the target active site were clearly observed. The obtained results suggest 5k as a potential candidate for anti-HIE therapy, which merits further investigation.

Oroxindin inhibits macrophage NLRP3 inflammasome activation in DSS-induced ulcerative colitis in mice via suppressing TXNIP-dependent NF-κB pathway.

Oroxindin is a flavonoid isolated from the traditional Chinese medicine Huang-Qin, which has shown various pharmacological activities including anti-inflammatory, antitumor, antioxidant, etc. Thus far, the effect of oroxindin on colonic inflammation and the underlying mechanism remain unknown. In this study, we investigated the tissue distribution of oroxindin and its therapeutic effects on ulcerative colitis (UC) as well as the underlying mechanisms. UC model was established in mice by administrating dextran sulfate sodium (DSS) in drinking water for 7 d. We first showed that oroxindin was largely absorbed by the colon as an active ingredient after normal mice received Huang-Qin-Tang, a traditional Chinese medicine decoction. UC mice were then treated with oroxindin (12.5, 25, 50 mg ·kg-1 ·d-1, i.g.) for 10 d. We found that oroxindin treatment greatly suppressed massive macrophages infiltration and attenuated pathological changes in colonic tissue. Furthermore, oroxindin treatment significantly inhibited the generation of IL-1ß and IL-18 in the colon via inhibiting the nucleotide-binding oligomerization domain-like receptor 3 (NLRP3) inflammasome formation and activation. In cultured macrophages, LPS induced NLRP3 inflammasome formation and caspase-1 activation, which were suppressed by oroxindin (12.5-50 µM). In LPS-treated macrophages, oroxindin dose-dependently restored the expression of TXNIP protein, leading to suppressing TXNIP-dependent NF-κB activation. In conclusion, these results demonstrate that oroxindin could be absorbed by the colon and attenuate inflammatory responses via inhibiting NLRP3 inflammasome formation and activation, which is related to the inhibitory effect on TXNIP-dependent NF-κB-signaling pathway. Hence, oroxindin has the potential of becoming an effective drug for treating UC.

Preparation and Neuroprotective Activity of Glucuronomannan Oligosaccharides in an MPTP-Induced Parkinson's Model.

Parkinson's disease (PD), characterized by dopaminergic neuron degeneration in the substantia nigra and dopamine depletion in the striatum, affects up to 1% of the global population over 50 years of age. Our previous study found that a heteropolysaccharide from Saccharina japonica exhibits neuroprotective effects through antioxidative stress. In view of its high molecular weight and complex structure, we degraded the polysaccharide and subsequently obtained four oligosaccharides. In this study, we aimed to further detect the neuroprotective mechanism of the oligosaccharides. We applied MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) to induce PD, and glucuronomannan oligosaccharides (GMn) was subsequently administered. Results showed that GMn ameliorated behavioral deficits in Parkinsonism mice. Furthermore, we observed that glucuronomannan oligosaccharides contributed to down-regulating the apoptotic signaling pathway through enhancing the expression of tyrosine hydroxylase (TH) in dopaminergic neurons. These results suggest that glucuronomannan oligosaccharides protect dopaminergic neurons from apoptosis in PD mice.

Probiotics, prebiotics, and synbiotics regulate the intestinal microbiota differentially and restore the relative abundance of specific gut microorganisms.

Fermented milk is an effective carrier for probiotics, the consumption of which improves host health. The beneficial effects of probiotics, prebiotics, and synbiotics on gut dysbiosis have been reported previously. However, the way in which specific probiotics, prebiotics, and synbiotics regulate intestinal microbes remains unclear. Therefore, the probiotics Lactobacillus rhamnosus AS 1.2466 and Lactobacillus delbrueckii ssp. bulgaricus ATCC 11842 and the prebiotics xylooligosaccharide and red ginseng extracts were fed to mice to determine their effects on the intestinal microbiota. Then, mice were administered xylooligosaccharide and L. rhamnosus (synthesis) by gavage, and the number of L. rhamnosus was determined in the intestine at different times. The results show that probiotics and prebiotics can quickly reduce the Firmicutes/Bacteroidetes ratio, inhibit harmful bacteria (such as Klebsiella and Escherichia coli), and accelerate the recovery of beneficial intestinal microorganisms (such as Lactobacillus). In a complex intestinal microecology, different probiotics and prebiotics have different effects on specific intestinal microorganisms that cannot be recovered in the short term. In addition, after 20 d of intragastric xylooligosaccharide addition at 0.12 g/kg of body weight, L. rhamnosus colonization in the mouse ileum was 7.48 log cfu/mL, which was higher than in the low-dose group, prolonging colonization time and increasing the number of probiotics in the intestine. Therefore, this study demonstrated that probiotics and prebiotics can promote the balance of intestinal microbiota by regulating specific microbes in the intestine, and the effects of a suitable combination of synbiotics are beneficial, laying the foundation for the development of new dairy products rich in synbiotics.

Scutellarin, a modulator of mTOR, attenuates hepatic insulin resistance by regulating hepatocyte lipid metabolism via SREBP-1c suppression.

High levels of consumption of saturated lipids have been largely associated with the increasing prevalence of metabolic diseases. In particular, saturated fatty acids such as palmitic acid (PA) have been implicated in the development of insulin resistance (IR). Scutellarin (Scu) is one of the effective traditional Chinese medicines considered beneficial for liver diseases and diabetes. In this study, we investigated the effect of Scu on IR and lipid metabolism disorders in vitro and in high fat diet (HFD)-fed mice. In vitro, we found that Scu decreased insulin-dependent lipid accumulation and the mRNA expression of CD36, Fasn, and ACC in PA-treated HepG2 cells. Additionally, Scu upregulated Akt phosphorylation and improved the insulin signalling pathway. Moreover, Scu downregulated mammalian target of rapamycin (mTOR) phosphorylation and the n-SREBP-1c protein level and also reduced lipid accumulation via the mTOR-dependent pathway, as confirmed by the molecular docking of Scu to mTOR. In HFD-fed C57BL/6 mice, Scu improved oral glucose tolerance, pyruvate tolerance and the IR index and also increased the Akt phosphorylation level. Moreover, Scu reduced hepatocyte steatosis, decreased lipid accumulation and triglyceride levels, inhibited mTOR phosphorylation, and decreased the SREBP-1c level in the liver. Taken together, these findings suggest that Scu ameliorates hepatic IR by regulating hepatocyte lipid metabolism via the mTOR-dependent pathway through SREBP-1c suppression.