Genetic and environmental circadian disruption induce weight gain through changes in the gut microbiome.

OBJECTIVE: Internal clocks time behavior and physiology, including the gut microbiome, in a circadian (∼24 h) manner. Mismatch between internal and external time, e.g. during shift work, disrupts circadian system coordination promoting the development of obesity and type 2 diabetes (T2D). Conversely, body weight changes induce microbiota dysbiosis. The relationship between circadian disruption and microbiota dysbiosis in metabolic diseases, however, remains largely unknown. METHODS: Core and accessory clock gene expression in different gastrointestinal (GI) tissues were determined by qPCR in two different models of circadian disruption - mice with Bmal1 deficiency in the circadian pacemaker, the suprachiasmatic nucleus (Bmal1SCNfl/-), and wild-type mice exposed to simulated shift work (SSW). Body composition and energy balance were evaluated by nuclear magnetic resonance (NMR), bomb calorimetry, food intake and running-wheel activity. Intestinal permeability was measured in an Ussing chamber. Microbiota composition and functionality were evaluated by 16S rRNA gene amplicon sequencing, PICRUST2.0 analysis and targeted metabolomics. Finally, microbiota transfer was conducted to evaluate the functional impact of SSW-associated microbiota on the host's physiology. RESULTS: Both chronodisruption models show desynchronization within and between peripheral clocks in GI tissues and reduced microbial rhythmicity, in particular in taxa involved in short-chain fatty acid (SCFA) fermentation and lipid metabolism. In Bmal1SCNfl/- mice, loss of rhythmicity in microbial functioning associates with previously shown increased body weight, dysfunctional glucose homeostasis and adiposity. Similarly, we observe an increase in body weight in SSW mice. Germ-free colonization experiments with SSW-associated microbiota mechanistically link body weight gain to microbial changes. Moreover, alterations in expression of peripheral clock genes as well as clock-controlled genes (CCGs) relevant for metabolic functioning of the host were observed in recipients, indicating a bidirectional relationship between microbiota rhythmicity and peripheral clock regulation. CONCLUSIONS: Collectively, our data suggest that loss of rhythmicity in bacteria taxa and their products, which likely originates in desynchronization of intestinal clocks, promotes metabolic abnormalities during shift work.

The intestinal clock drives the microbiome to maintain gastrointestinal homeostasis.

Diurnal (i.e., 24-hour) oscillations of the gut microbiome have been described in various species including mice and humans. However, the driving force behind these rhythms remains less clear. In this study, we differentiate between endogenous and exogenous time cues driving microbial rhythms. Our results demonstrate that fecal microbial oscillations are maintained in mice kept in the absence of light, supporting a role of the host's circadian system rather than representing a diurnal response to environmental changes. Intestinal epithelial cell-specific ablation of the core clock gene Bmal1 disrupts rhythmicity of microbiota. Targeted metabolomics functionally link intestinal clock-controlled bacteria to microbial-derived products, in particular branched-chain fatty acids and secondary bile acids. Microbiota transfer from intestinal clock-deficient mice into germ-free mice altered intestinal gene expression, enhanced lymphoid organ weights and suppressed immune cell recruitment. These results highlight the importance of functional intestinal clocks for microbiota composition and function, which is required to balance the host's gastrointestinal homeostasis.

Preparation and Hydration of Brownmillerite-Belite-Sulfoaluminate Cement.

Brownmillerite-belite-sulfoaluminate clinker with different contents of brownmillerite were designed and successfully prepared by using limestone (LS), aluminum tailings (AT), aluminum mine (AM), and anhydrite (AH) calcined at 1330 °C for 30 min. Then, three kinds of brownmillerite-belite-sulfoaluminate cement (BBSC) were obtained by grinding mixtures of the clinker and AH. Hydration and mechanical performances of the prepared BBSC were thus intensively studied. The increase in brownmillerite in BBSC decreased the hydration exothermic rate and delayed the renewed rapid formation of AFt at early hydration stages. However, the formation of C2AS·8H2O would be promoted, where the higher the brownmillerite content in BBSC, the earlier the C2AS·8H2O formed. The increase in brownmillerite might change the morphologies of the formed AFt, grass-shaped AFt enriched in iron would be the main hydration products in BBSC with a higher content of brownmillerite. The increase in brownmillerite content contributed to the stability improvement in flexural strength and the stable growth in the compressive strength of BBSC. The appropriate content of brownmillerite (20 wt%) can balance the whole hydration reaction process, which was conducive to the development of BBSC mechanical strength, the decrease in the hydration heat release, and the volume stability of hardened pastes.

Procyanidin B2 mitigates behavioral impairment and protects myelin integrity in cuprizone-induced schizophrenia in mice.

Numerous studies have suggested that neuropathological changes in schizophrenia may be related to damage to white matter or demyelination. Procyanidin B2, which is a constituent of many fruits such as grapes and strawberries, has various biological activities such as anti-inflammatory and anti-tumor activity, as has been reported. This study aimed to estimate the effects of procyanidin B2 on behavioral impairment and the protection of myelin integrity in a cuprizone-induced schizophrenia model. Mice were exposed to cuprizone (0.2% w/w in chow) for five weeks to induce schizophrenia-like behavioral changes and demyelination. Procyanidin B2 (20 or 100 mg kg-1 day-1) or vehicle was administered orally to mice after withdrawal from cuprizone. Behavioral impairment was detected with an open-field test, a rotarod test and a Morris water maze. Myelin integrity was assessed using LFB staining and MBP expression, including immunofluorescence and western blotting. In addition, enhancements in the expression of HO-1 and NQO1 suggested that procyanidin B2 may regulate oxidative homeostasis via promoting the translation of Nrf2 to the nucleus. Data indicated that procyanidin B2 could mitigate behavioral impairment and protect myelin integrity in the cuprizone-induced model via regulating oxidative stress by activating Nrf2 signaling.

Quantitative determination of carcinogenic mycotoxins in human and animal biological matrices and animal-derived foods using multi-mycotoxin and analyte-specific high performance liquid chromatography-tandem mass spectrometric methods.

A sensitive and reliable multi-mycotoxin-based method was developed to identify and quantify several carcinogenic mycotoxins in human blood and urine, as well as edible animal tissues, including muscle and liver tissue from swine and chickens, using liquid chromatography-tandem mass spectrometry (LC-MS/MS). For the toxicokinetic studies with individual mycotoxins, highly sensitive analyte-specific LC-MS/MS methods were developed for rat plasma and urine. Sample purification consisted of a rapid 'dilute and shoot' approach in urine samples, a simple 'dilute, evaporate and shoot' approach in plasma samples and a 'QuEChERS' procedure in edible animal tissues. The multi-mycotoxin and analyte-specific methods were validated in-house: The limits of detection (LOD) for the multi-mycotoxin and analyte-specific methods ranged from 0.02 to 0.41 µg/kg (µg/L) and 0.01 to 0.19 µg/L, respectively, and limits of quantification (LOQ) between 0.10 to 1.02 µg/kg (µg/L) and 0.09 to 0.47 µg/L, respectively. Apparent recoveries of the samples spiked with 0.25 to 4 µg/kg (µg/L) ranged from 60.1% to 109.8% with relative standard deviations below 15%. The methods were successfully applied to real samples. To the best of our knowledge, this is the first study carried out using a small group of patients from the Chinese population with hepatocellular carcinoma to assess their exposure to carcinogenic mycotoxins using biomarkers. Finally, the multi-mycotoxin method is a useful analytical method for assessing exposure to mycotoxins edible in animal tissues. The analyte-specific methods could be useful during toxicokinetic and toxicological studies.

Myricetin alleviates cuprizone-induced behavioral dysfunction and demyelination in mice by Nrf2 pathway.

Multiple sclerosis (MS) is a demyelinating disease occurring in the central nervous system. In the present study, we evaluated the function of myricetin on the alleviation of behavioral dysfunction and myelin protection in the cuprizone-induced demyelination model. Mice were daily fed with fodder including 0.2% cuprizone and were administrated myricetin (100 mg kg-1) by gavage administration for 5 weeks. The treatment of myricetin ameliorated hyper-locomotion and behavior impairment induced by cuprizone toxicity. With the administration of myricetin, the demyelinating lesion was lessened via increasing the LFB staining area and myelin phosphatide protein (MBP) expression. In addition, myricetin evidently promoted Nrf2 translocation in the nuclear fraction and enhanced the HO-1 and NQO1 expression levels. Our data revealed that myricetin may be a potential candidate for mitigating motor defects and demyelination in a cuprizone-induced mouse model via activating the Nrf2 pathway.

Fucoidan from Undaria pinnatifida prevents vascular dysfunction through PI3K/Akt/eNOS-dependent mechanisms in the l-NAME-induced hypertensive rat model.

Despite major scientific advances in its prevention, treatment and care, hypertension remains a serious condition that might lead to long-term complications such as heart disease and stroke. The great majority of forms of hypertension eventually result from an increased vasomotor tone activity that is regulated by endothelial NOS (eNOS) in vascular endothelium. Here, we examined the effect of fucoidan on eNOS activation in human umbilical vein endothelial cells (HUVECs). We also examined the effects of functional components of Undaria pinnatifida fucoidan on blood pressure and vascular function in eNOS inhibition-induced hypertensive rats in vivo. Our results suggest that fucoidan increased nitric oxide production by activating eNOS and Akt phosphorylation, which could be impaired by Akt or eNOS inhibitors. In the hypertensive rat model, treatment of fucoidan resulted in potent and persistent reduction of high blood pressure (BP) even after drug withdrawal. Our results showed that the mechanisms might involve protection against vascular structure damage, enhanced endothelium-independent vascular function and inhibition of abnormal proliferation of smooth muscle cells, which are mediated by the Akt-eNOS signaling pathway. Moreover, fucoidan treatment reduced the vascular inflammation and oxidative stress control caused by iNOS expression. Together, these results support a putative role of fucoidan in hypertension prevention and treatment.

Procyanidin B2 attenuates neurological deficits and blood-brain barrier disruption in a rat model of cerebral ischemia.

SCOPE: Disruption of the blood-brain barrier (BBB) is a major pathogenic mechanism of neurological dysfunction and death after ischemic stroke. The aim of our study was to investigate the effect of procyanidin B2 (PB), a bioactive food compound, on BBB disruption induced by ischemic stroke and explore the underlying mechanism. METHODS AND RESULTS: PB was administrated intragastrically once a day starting at 3 h after transient middle cerebral artery occlusion (MCAO). PB treatment significantly decreased the infarction volume, brain edema, and neurological deficits after MCAO. PB prevented BBB disruption against ischemic stroke, as indicated by the reduction of Evans blue leakage and IgG levels. These results were also corroborated by immunofluorescence staining and Western blot analysis of ZO-1. Additionally, levels of reactive oxygen species and malondialdehyde were lessened in the ipsilateral ischemic area of brain by PB. The activities of antioxidant enzymes were elevated. Meanwhile, PB reversed the suppression of NF-E2-related factor nuclear translocation, and increased the protein expression of HO-1, GSTα, and NQO1 in the ipsilateral ischemic area of brain. CONCLUSION: PB attenuates neurological deficits and BBB disruption in a rat model of cerebral ischemia, and the neuroprotection of PB is associated with activation of NF-E2-related factor pathway.

Characterization and hepatoprotective effect of polysaccharides from Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H. F. Chou sarcocarp.

The polysaccharides from Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H. F. Chou sarcocarp (PWJS) is evaluated for the chemical composition, antioxidant activity and hepatoprotective effect. The characteristics of PWJS were determined by FT-IR spectral and HPLC analysis. The antioxidant activity was investigated using in vitro systems. An in vivo study of PWJS against CCl4 induced liver injury was also conducted. HPLC analysis showed that PWJS is an acidic heteropolysaccharide, rich in glucose (38.59%), arabinose (23.16%), galacturonic acid (17.64%) and galactose (10.44%). PWJS displayed strong antioxidant activity in vitro. In the in vivo study, PWJS treatment lowered the serum levels of ALT and AST in CCl4-intoxicated mice. Additionally, levels of antioxidant enzymes (SOD and CAT) and GSH were elevated in liver damage mice by PWJS intervention, while content of MDA was lessened. Meanwhile, PWJS reverses the suppression of Nrf2 nuclear translocation, and increases the protein expression of HO-1, GSTα and NQO1 in liver damage mice. Hematoxylin-eosin staining showed that the condition of liver damage was mitigated. This study demonstrates that PWJS reverses hepatotoxicity in CCl4-intoxicated mice through the mechanisms of antioxidant activity, as well as an augmentation of the Nrf2 pathway in liver tissue.