Trace metal elements: a bridge between host and intestinal microorganisms.

Trace metal elements, such as iron, copper, manganese, and zinc, are essential nutrients for biological processes. Although their intake demand is low, they play a crucial role in cell homeostasis as the cofactors of various enzymes. Symbiotic intestinal microorganisms compete with their host for the use of trace metal elements. Moreover, the metabolic processes of trace metal elements in the host and microorganisms affect the organism's health. Supplementation or the lack of trace metal elements in the host can change the intestinal microbial community structure and function. Functional changes in symbiotic microorganisms can affect the host's metabolism of trace metal elements. In this review, we discuss the absorption and transport processes of trace metal elements in the host and symbiotic microorganisms and the effects of dynamic changes in the levels of trace metal elements on the intestinal microbial community structure. We also highlight the participation of trace metal elements as enzyme cofactors in the host immune process. Our findings indicate that the host uses metal nutrition immunity or metal poisoning to resist pathogens and improve immunity.

Ludangshen oral liquid for treatment of convalescent COVID-19 patients: a randomized, double-blind, placebo-controlled multicenter trial.

OBJECTIVE: To explore the effect of Ludangshen oral liquid for treatment of convalescent patients with coronavirus disease 2019 (COVID-19) with randomized, double-blind, placebo-controlled multicenter method. METHODS: 200 convalescent COVID-19 patients who had symptoms related to decreased digestive and respiratory function were randomly divided to either receive Ludangshen oral liquid or placebo for 2 weeks. The severity of clinical symptoms including fatigue, anorexia, abdominal distension, loose stools, and shortness of breath were assessed by visual analogue scale and observed at before and after treatment. The improvement and resolution rates of clinical symptoms were evaluated. Full analysis set (FAS) and per-protocol set (PPS) were used for statistical analyses. Adverse events were recorded during the study. RESULTS: 8 patients did not complete the study. After 2 weeks of treatment, both FAS and PPS results showed that patients in Ludangshen group had significantly lower score of fatigue, anorexia, loose stools, and shortness of breath than placebo group (P < 0.05), while there was no significant difference in distention (P > 0.05). The improvement rate of fatigue, anorexia, distension, loose stools and shortness of breath were significantly higher in Ludangshen group (P < 0.05), as well as the resolution rates (P < 0.05) except for shortness of breath (P > 0.05). There were two cases of adverse events, with one nose bleeding in Ludangshen group and one headache in placebo group. CONCLUSION: The study suggested that two weeks of Ludangshen oral liquid treatment may have certain effects for convalescent COVID-19 patients on improving digestive and respiratory symptoms including fatigue, anorexia, loose stools and shortness of breath, which may be one of the choices for management of convalescent COVID-19 patients with digestive and respiratory symptoms.

Chinese natural compound decreases pacemaking of rabbit cardiac sinoatrial cells by targeting second messenger regulation of f-channels.

Tongmai Yangxin (TMYX) is a complex compound of the Traditional Chinese Medicine (TCM) used to treat several cardiac rhythm disorders; however, no information regarding its mechanism of action is available. In this study we provide a detailed characterization of the effects of TMYX on the electrical activity of pacemaker cells and unravel its mechanism of action. Single-cell electrophysiology revealed that TMYX elicits a reversible and dose-dependent (2/6 mg/ml) slowing of spontaneous action potentials rate (-20.8/-50.2%) by a selective reduction of the diastolic phase (-50.1/-76.0%). This action is mediated by a negative shift of the If activation curve (-6.7/-11.9 mV) and is caused by a reduction of the cyclic adenosine monophosphate (cAMP)-induced stimulation of pacemaker channels. We provide evidence that TMYX acts by directly antagonizing the cAMP-induced allosteric modulation of the pacemaker channels. Noticeably, this mechanism functionally resembles the pharmacological actions of muscarinic stimulation or ß-blockers, but it does not require generalized changes in cytoplasmic cAMP levels thus ensuring a selective action on rate. In agreement with a competitive inhibition mechanism, TMYX exerts its maximal antagonistic action at submaximal cAMP concentrations and then progressively becomes less effective thus ensuring a full contribution of If to pacemaker rate during high metabolic demand and sympathetic stimulation.

Identification of epigenetic modifications mediating the antagonistic effect of selenium against cadmium-induced breast carcinogenesis.

The antagonistic effect of selenium (Se) against cadmium (Cd)-induced breast carcinogenesis was reported, but underlying mechanisms were unclear. The aim of this study was to identify the epigenetically regulated genes and biological pathways mediating the antagonistic effect. We exposed MCF-7 cells to Cd and Se alone or simultaneously. Cell proliferation was assessed by MTT assay, and differential epigenome (DNA methylation, microRNA, and long non-coding RNA) was obtained by microarrays. We cross-verified the epigenetic markers with differential transcriptome, and the ones modulated by Cd and Se in opposite directions were regarded to mediate the antagonistic effect. The epigenetically regulated genes were validated by using gene expression data in human breast tissues. We further assessed the biological functions of these validated genes. Our results showed that Se alleviated the proliferative effect of Cd on MCF-7 cell. A total of 10 epigenetically regulated genes were regarded to mediate the antagonistic effect, including APBA2, KIAA0895, DHX35, CPEB3, SVIL, MYLK, ZFYVE28, ABLIM2, GRB10, and PCDH9. Biological function analyses suggested that these epigenetically regulated genes were involved in multiple cancer-related pathways, such as focal adhesion and PI3K/Akt pathway. In conclusion, we provided evidence that Se antagonized the Cd-induced breast carcinogenesis via epigenetic modification and revealed the critical pathways.

Immobilized beta2-adrenergic receptor: A powerful chromatographic platform for drug discovery and evaluation of drug-like property for natural products.

Drug discovery based on natural products like medicinal herbs remains challenging due to the technique limitations for rapidly screening and validating leads. To address the challenges, we employ the immobilized ß2- adrenergic recepotor (ß2-AR), an identified target of asthma, as the stationary phase in chromatographic column to screen compounds extracted from Stemonae Radix, Playtycodonis Radix, and Glycyrrhizae Radix et Rhizoma. To analyze binding properties of the extracted compounds to the immobilized receptors, we measured their retention behavior in the receptor chromatography and compared with six clinical asthma drugs. We identified tuberostemonine, platycodin D, and glycyrrhizic acid as the potential leads against asthma by our ß2-AR chromatography coupled with mass spectrum (MS). The association constants of the three compounds to ß2-AR were 2.85 × 10-5, 2.55 × 10-4, and 4.07 × 10-6 M with the dissociation rate constants of 6.91 ± 0.35, 11.88 ± 0.60, and 9.49 ± 0.64 min-1, respectively. Tuberostemonine, a pentacyclic Stemona alkaloids, presented the most optimum values of binding efficiency index (BEI) and surface efficiency index (SEI) as close to the diagonal of SEI-BEI optimization plane when it is compared with platycodin D, glycyrrhizic and the six clinical drugs. Our results suggest that tuberostemonine is a promising natural product to be developed for treating asthma because it exhibits better drug-like binding properties to ß2-AR than the clinical drugs. As such, we demonstrate a chromatographic strategy to identify bioactive natural products based on the ß2-AR immobilization, which can be widely adopted to screen natural products from mixture of herbal extracts.

IRW and IQW Reduce Colitis-Associated Cancer Risk by Alleviating DSS-Induced Colonic Inflammation.

BACKGROUND AND OBJECTIVE: Bioactive peptides exert great influence in animals and human health by targeting gastrointestinal tracts. The colitis model of mice was induced by dextran sulfate sodium (DSS). Thirty-two 8-week-old mice weighing 23 g on average were randomly assigned to four groups of 8 each: mice fed basal diet (CON), mice fed basal diet with 5% DSS (DSS), mice fed 0.03% IRW with 5% DSS (IRW-DSS), and mice fed 0.03% IRW with 5% DSS (IQW-DSS). After an adaptation period of 3 days, on day 8, all mice were slaughtered. Serum samples were collected to determine the level of amino acids; colonic tissue was quick-frozen for the determination of gene expression. METHODS: The aim of this study was to assess the ability of two kinds of peptides (IRW and IQW) to repair intestinal inflammatory in the DSS-induced model in accordance with serum amino acids and intestinal inflammatory factors. RESULTS: The results demonstrated that the addition of IRW and IQW had a mitigating effect on DSS-induced intestinal inflammation. The level of Asp decreased in the serum of mice supplemented with IRW-DSS (P < 0.05), and IQW enhanced the level of Leu, but lowered the level of Ser (P < 0.05). IQW and IRW addition reduced the level of TNF-α and IL-17 (P < 0.05). No other significant effects were observed. CONCLUSIONS: The present study demonstrated that intracolic administration of IRW and IQW might be a novel option for preventing inflammatory bowel disease via regulating the level of serum amino acid and enhancing the intestinal immune defense.

Effects of Lactobacillus plantarum 15-1 and fructooligosaccharides on the response of broilers to pathogenic Escherichia coli O78 challenge.

One-day-old broilers were randomly allocated to five treatment groups: basal diet and orally administered sterile saline (negative control, n-control); basal diet challenged with E. coli O78 (positive control, p-control); basal diet supplemented with 1×108 CFU/kg L. plantarum 15-1 and challenged with E. coli O78 (LP); basal diet supplemented with 5 g/kg fructooligosaccharides (FOS) and challenged with E. coli O78 (FOS); and basal diet supplemented with both L. plantarum 15-1 and FOS and challenged with E. coli O78 (LP+FOS). The broilers in the LP, FOS, and LP+FOS groups displayed a decrease of crypt depth at day 14 compared with the control groups. Furthermore, at days 14 and 21, the broilers in the LP group exhibited reduced serum levels of diamine oxidase (DAO) compared with the p-control group (p<0.05), and the broilers in the LP+FOS group showed increased serum concentrations of IgA and IgG relative to both control groups and decreased DAO levels compared with the p-control group (p<0.05). Moreover, the LP group displayed higher levels of acetic acid and total short-chain fatty acids (SCFAs) compared with the p-control group at day 14 (p<0.05), and the FOS group showed higher levels of valeric acid and total SCFAs at day 21 (p<0.05). The LP+FOS group also displayed a higher level of butyric acid at day 14 (p<0.05). In conclusion, dietary supplementation with FOS improved the growth performance, while supplementation with L. plantarum 15-1 and FOS improved intestinal health by increasing the levels of SCFAs and mitigating the damage caused by E. coli O78, thus preventing intestinal damage and enhancing the immune response.

Concurrent HER or PI3K Inhibition Potentiates the Antitumor Effect of the ERK Inhibitor Ulixertinib in Preclinical Pancreatic Cancer Models.

Effective treatment for pancreatic ductal adenocarcinoma (PDAC) is an urgent, unmet medical need. Targeting KRAS, the oncogene that is present in >95% of PDAC, is a heavily pursued strategy, but remains unsuccessful in the clinic. Therefore, targeting key effector cascades of KRAS oncoprotein, particularly the mitogenic RAF-MEK-ERK pathway, represents the next best strategy. However, RAF or MEK inhibitors have failed to show clinical efficacy in PDAC. Several studies have shown that cancer cells treated with RAF or MEK inhibitors adopt multiple mechanisms to reactivate ERK signaling. Therefore, development of ERK-specific inhibitors carries the promise to effectively abrogate this pathway. Ulixertinib (or BVD-523) is a first-in-class ERK-specific inhibitor that has demonstrated promising antitumor activity in a phase I clinical trial for advanced solid tumors with NRAS and BRAF mutations, providing a strong rationale to test this inhibitor in PDAC. In this study, we show that ulixertinib effectively inhibits in vitro growth of multiple PDAC lines and potentiates the cytotoxic effect of gemcitabine. Moreover, we found that PDAC cells treated with ulixertinib upregulates the parallel PI3K-AKT pathway through activating the HER/ErbB family proteins. Concurrent inhibition of PI3K or HER proteins synergizes with ulixertinib in suppressing PDAC cell growth in vitro and in vivo Overall, our study provides the preclinical rationale for testing combinations of ulixertinib with chemotherapy or PI3K and HER inhibitors in PDAC patients. Mol Cancer Ther; 17(10); 2144-55. ©2018 AACR.

Baicalin and its metabolites suppresses gluconeogenesis through activation of AMPK or AKT in insulin resistant HepG-2 cells.

Scutellaria baicalensis Georgi (S. baicalensis), as a traditional Chinese herbal medicine, is an important component of several famous Chinese medicinal formulas for treating patients with diabetes mellitus. Baicalin (BG), a main bioactive component of S. baicalensis, has been reported to have antidiabetic effects. However, pharmacokinetic studies have indicated that BG has poor oral bioavailability. Therefore, it is hard to explain the pharmacological effects of BG in vivo. Interestingly, several reports show that BG is extensively metabolized in rats and humans. Therefore, we speculate that the BG metabolites might be responsible for the pharmacological effects. In this study, BG and its three metabolites (M1-M3) were examined their effects on glucose consumption in insulin resistant HepG-2 cells with a commercial glucose assay kit. Real-time PCR and western blot assay were used to confirm genes and proteins of interest, respectively. The results demonstrate that BG and its metabolites (except for M3) enhanced the glucose consumption which might be associated with inhibiting the expression of the key gluconeogenic genes, including glucose-6-phosphatase (G6Pase), phosphoenolypyruvate carboxykinase (PEPCK) and glucose transporter 2 (GLUT2). Further study found that BG and M1 could suppress hepatic gluconeogenesis via activation of the AMPK pathway, while M2 could suppress hepatic gluconeogenesis via activation of the PI3K/AKT signaling pathway. Taken together, our findings suggest that both BG and its metabolites have antihyperglycemic activities, and might be the active forms of oral doses of BG in vivo.

The Effects of Agave fourcroydes Powder as a Dietary Supplement on Growth Performance, Gut Morphology, Concentration of IgG, and Hematology Parameters in Broiler Rabbits.

This study was conducted to determine the effects of Agave fourcroydes powder as a dietary supplement on the growth performance, gut morphology, serum concentration of IgG, and the hematology parameters of broiler rabbits. A total of 32 rabbits [New Zealand × Californian] were weaned at 35 days. They were randomly selected for two dietary treatments (eight repetitions per treatment), which consisted of a basal diet and a basal diet supplemented with 1.5% dried-stem powder of A. fourcroydes. On day 60 from the initiation of treatment, gut histomorphology (duodenum and cecum), serum concentration of IgG, and hematology parameters were all measured. The results showed that A. fourcroydes powder supplementation improved (P < 0.05) the ADFI, ADG, and final BW. Correspondingly, this treatment increased (P < 0.05) the muscle and mucosa thickness and height and width of villi. However, duodenum crypts depth was lower (P < 0.05) when rabbits were fed with this natural product, compared with the basal diet treatment. Results also indicated that the A. fourcroydes powder increased (P < 0.05) the serum concentration of IgG but did not change the hematology parameters. This data indicates that A. fourcroydes powder, as a supplement, had beneficial effects on increasing the growth performance and serum concentration of IgG, as well as improving the gut morphology without affecting the hematology parameters in broiler rabbits.

A robust analytical method for measurement of phytoestrogens and related metabolites in serum with liquid chromatography tandem mass spectrometry.

A sensitive and robust method using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed for quantitation of 13 phytoestrogens and related metabolites in rat serum samples. A new type of column, the Kinetex core-shell C18 column, was applied for rapid separation of the target analytes in 10min. Two enzymes, sulfatase H-1 and gulcuronidase H-5 from Helix pomatia were compared on the efficiency of releasing the conjugated forms of the target analytes to their free forms in serum samples. The method detection limit (MDL) defined as three times the signal to noise ratio in spiked serum matrix-based solutions was in the range of 0.1-3.5ng/mL. The linear dynamic calibration was in the broad range of 0.2-500ng/mL for all target compounds. Thirty-two rat serum samples from the rats that were fed with diets containing either casein or soy protein isolates with various amounts of isoflavones for 8 weeks were analyzed for the target analytes with the developed method. Nine target analytes were detected in the serum samples. Those detectable compounds are all the metabolites of the dietary isoflavones, suggesting that the diet isoflavones were mostly metabolized to their metabolites in rat.

Indole alkaloids from the roots of Isatis indigotica and their inhibitory effects on nitric oxide production.

Three rare indole-2-S-glycosides, indole-3-acetonitrile-2-S-ß-D-glucopyranoside (1), indole-3-acetonitrile-4-methoxy-2-S-ß-D-glucopyranoside (2) and N-methoxy-indole-3-acetonitrile-2-S-ß-D-glucopyranoside (3), together with 11 known indole alkaloids were isolated from the roots of Isatis indigotica Fort. (Cruciferae). The structures of 1-3 were elucidated on the basis of mass spectrometry and extensive 1D and 2D NMR spectroscopy. All of the isolated compounds were tested for inhibitory activity against LPS-induced nitric oxide production in RAW 264.7 macrophages. A plausible biosynthesis pathway of 1-3 is also proposed.

Comparative study of adsorption of Pb(II) on native garlic peel and mercerized garlic peel.

A comparative study using native garlic peel and mercerized garlic peel as adsorbents for the removal of Pb(2+) has been proposed. Under the optimized pH, contact time, and adsorbent dosage, the adsorption capacity of garlic peel after mercerization was increased 2.1 times and up to 109.05 mg g(-1). The equilibrium sorption data for both garlic peels fitted well with Langmuir adsorption isotherm, and the adsorbent-adsorbate kinetics followed pseudo-second-order model. These both garlic peels were characterized by elemental analysis, Fourier transform infrared spectrometry (FT-IR), and scanning electron microscopy, and the results indicated that mercerized garlic peel offers more little pores acted as adsorption sites than native garlic peel and has lower polymerization and crystalline and more accessible functional hydroxyl groups, which resulted in higher adsorption capacity than native garlic peel. The FT-IR and X-ray photoelectron spectroscopy analyses of both garlic peels before and after loaded with Pb(2+) further illustrated that lead was adsorbed on the through chelation between Pb(2+) and O atom existed on the surface of garlic peels. These results described above showed that garlic peel after mercerization can be a more attractive adsorbent due to its faster sorption uptake and higher capacity.

Dietary supplementation of blueberry juice enhances hepatic expression of metallothionein and attenuates liver fibrosis in rats.

AIM: To investigate the effect of blueberry juice intake on rat liver fibrosis and its influence on hepatic antioxidant defense. METHODS: Rabbiteye blueberry was used to prepare fresh juice to feed rats by daily gastric gavage. Dan-shao-hua-xian capsule (DSHX) was used as a positive control for liver fibrosis protection. Liver fibrosis was induced in male Sprague-Dawley rats by subcutaneous injection of CCl4 and feeding a high-lipid/low-protein diet for 8 weeks. Hepatic fibrosis was evaluated by Masson staining. The expression of α-smooth muscle actin (α-SMA) and collagen III (Col III) were determined by immunohistochemical techniques. The activities of superoxide dismutase (SOD) and malondialdehyde (MDA) in liver homogenates were determined. Metallothionein (MT) expression was detected by real-time RT-PCR and immunohistochemical techniques. RESULTS: Blueberry juice consumption significantly attenuates CCl4-induced rat hepatic fibrosis, which was associated with elevated expression of metallothionein (MT), increased SOD activity, reduced oxidative stress, and decreased levels of α-SMA and Col III in the liver. CONCLUSION: Our study suggests that dietary supplementation of blueberry juice can augment antioxidative capability of the liver presumably via stimulating MT expression and SOD activity, which in turn promotes HSC inactivation and thus decreases extracellular matrix collagen accumulation in the liver, and thereby alleviating hepatic fibrosis.

[Study on extraction technology of Mosla chinensis volatile oil].

OBJECTIVE: To study the techniques of organic solvent extraction method and supercritical CO2 extraction for extracting Mosla chinensis Maxim volatile oil (MCMVO), and to analyze its chemical compositions. METHODS: Organic solvent extraction method and supercritical CO2 extraction were used to extract the oil and GC-MS was used to analyze its chemical compositions. RESULTS: The best extraction techniques of organic solvent method to extract volatile oil should be divided into two steps, total time was 210 minutes, the total proportions of input of the solvent and raw materials was 8:1 (ml:g), and temprature was 65 degrees C, its extraction rate was 1.83%. The MCMVO was extracted by supercritical CO2, and its extraction rate was 3.4%. GC-MS was used to analyze volatile oil, the results suggested MCMVO contain thymol, carvacrol, P-cycmene, humulene etc. The thymol had the highest content accounts for 56.25%, and the carvacrol was 19.21%. The content of thymol and carvacrol of MCMVO extracted by organic solvent was 58.33% and 22.54%. CONCLUSION: the content of thymol and carvacrol extracted by organic solvent extraction method is higher than that extracted by supercritical CO2 extraction method. Chemical compositions extracted by organic solvent extraction method are less than extracted by supercritical CO2 extraction method. 10 compositions are firstly extracted by supercritical CO2 extraction method.

[Influence of anoxia/reoxygenation on immunofunction of endothelial cells and effect of intervention with yisheng injection on it].

OBJECTIVE: To explore the influence of ischemia/reperfusion (anoxia/reoxygenation) on immunofunction of endothelial cells (ECs) and effect of intervention with Yisheng injection (YSI, a pure natural medicine) on it. METHODS: Model of ECs induced by anoxia/reoxygenation was established to mimic ECs ischemia/reperfusion injury in vivo with human umbilical vein endothelial cell line ECV304. Then YSI was used to intervene the anoxia/reoxygenation process. Nuclear transcriptional factor-kappa B (NF-kappa B) was exhibited by fluorescent staining, HLA-ABC, HLA-DR, CD86 and CD54 were detected by flow cytometry. Mixed endothelial cell-lymphocyte reaction (MELR) was conducted to examine the proliferation of lymphocyte, production of IL-2 and percentage of apoptotic lymphocyte. RESULTS: Anoxia/reoxygenation made the ECV304 cell became round, shrunk and abscised, with increased plasma NF-kappa B, and changed from positive cytoplasm to positive nucleus. HLA-ABC, HLA-DR and CD86 on surface of cells increased but CD54 showed unchanged. MELR showed the incorporation of 3H-TdR and production of IL-2 increased significantly and the percentage of apoptotic lymphocyte decreased. After YSI intervention, the ECV304 cell shaped recovered, NF-kappa B expression didn't down-regulated, but the percentage of positive cells decreased, changed to positive dominant. Besides, reversal changes were shown in other parameters. CONCLUSION: Anoxia/reoxygenation influences some important immune related molecules in ECV304 cells, YSI could antagonizing these influences to maintain the immune function of endothelial cells in a relative normal manner.

[A study on the protective mechanism of yisheng injection against the anoxia-reoxygenation injury to endothelial cells].

OBJECTIVE: To explore the mechanism of ischemia reperfusion injury (IRI) and the protective effect of Yisheng injection on endothelial cells (ECs). METHODS: Human umbilical veins endothelial cell line ECV304 was cultured in RPMI medium 1640 without glucose under 100% N2 for one and a half hours, and then in RPMI medium 1640 with glucose under normal conditions for 5 hours to mimic ECs' IRI posttransplantaion. A pure nature medicine, Yisheng injection was added into the medium in experimental group. Intracellular calcium and mitochondrial were shown through flourescent staining. The activities of succinic dehydrogenase (SDH) and lactic dehydrogenase (LDH) were detected by cytochemical staining. The concentrations of superoxide dismutase (SOD), malonaldehyde (MDA) and nitrous oxide (NO) in culture medium were determined. RESULTS: After treatment with anoxia-reoxygenation, the ECs' morphologic changes were observed, and intracellular calcium concentration, LDH activity, MDA concentration became higher. Meanwhile, mitochondrial membrane potential, concentrations of SOD and NO were lower. Yisheng injection made these changes disappear or become less. CONCLUSION: Anoxia-reoxygenation induces lipid peroxidation, calcium superrcharge in ECs, and damage to mitochondrial function. Yisheng injection can reverse these changes, thus protecting the endothelial cells.