Dietary crude protein time-dependently modulates the bacterial community and metabolites and changes dietary nutrient efficiency in growing pigs.

The reduced nutrient digestibility of low-protein (LP) diets has been shown to be caused by the weakened fermentative capacity of the post-gut flora. The dynamic regulation of dietary protein contents on post-gut microbial population and fermentative metabolism is unclear. Twelve growing barrows (19.9 ± 0.8 kg) fitted with a T-cannula at the blind end of the cecum were randomly administered a high-protein (HP, 21.5% crude protein [CP]) diet or an LP (15.5% CP) diet for 28 d. The cecal content and feces were collected at d 1, 14, and 28 of the experiment for microflora structures and metabolite concentrations analysis. The nutrient digestibility coefficient and plasma biochemical parameters were also determined. Compared with the HP treatment, the LP treatment showed decreased plasma urea nitrogen concentration and apparent total tract digestibility of dry matter, gross energy, and CP (P < 0.01). In addition, urinary nitrogen losses, total nitrogen losses, and daily nitrogen retention in the LP treatment were lower than those in the HP treatment (P < 0.01), and the nitrogen retention-to-nitrogen intake ratio in the LP treatment was increased (P < 0.01). The HP group showed increased cecal total short-chain fatty acids (SCFA) concentration and fecal propionate, butyrate, and total SCFA concentrations (P < 0.05) on d 14 and 28, which may be mainly related to the elevated abundance of SCFA-producing bacteria, such as Ruminococcus, Lactobacillus, and Prevotella (P < 0.05). Probiotics, such as Bifidobacterium, Bacteroidales S24-7, and Rikenella, enriched in the LP treatment possibly contributed to reduced plasma endotoxin content. The differences in the abundances of almost all the above-mentioned flora appeared on d 28 but not d 14. Likewise, differences in the Simpson and Shannon indices and clustering patterns of the microbiota between treatments were also only observed on d 28. To sum up, in a time-dependent manner, the LP diet increased probiotics with gut-improving functions and decreased SCFA-producing bacteria, which may cause enhanced intestine health and reduced nutrient digestibility.

Thymoquinone induces apoptosis in temozolomide-resistant glioblastoma cells via the p38 mitogen-activated protein kinase signaling pathway.

Temozolomide (TMZ) can cross the blood-brain barrier (BBB) and deliver methyl groups to the purine (guanine) bases of DNA, leading to mispairing during DNA replication and subsequent cell death. However, increased expression of the repair enzyme methyl guanine methyltransferase (MGMT), which removes methyl groups from purine bases, counteracts methylation by TMZ. We evaluated the anticancer potential of thymoquinone (TQ), a hydrophobic flavonoid that inhibits resistance and induces apoptosis in various cancer cells, both in vitro and in vivo. In vitro experiments showed that compared with the Hs683 and M059J cell lines, U251 cells were more sensitive to TMZ. Compared to U251 cells, U251R cells, a TMZ drug-resistant strain established in this study, are characterized by increased expression of phosphorylated extracellular signal-regulated kinase (p-ERK) and MGMT. TQ treatments induced apoptosis in all cell lines. The p38 mitogen-activated protein kinase signal pathway was mainly activated in U251 and U251R cells; however, p-ERK and MGMT upregulation could not suppress TQ effects. Furthermore, si-p38 pretreatment of U251R cells in TQ treatments inhibited cell apoptosis. We speculate that TQ contributed to the phosphorylation and activation of p38, but not of ERK-induced apoptosis (irrespective of TMZ resistance). In vivo, U251R-derived tumors subcutaneously inoculated in nude mice exhibited significant tumor volume reduction after TQ or TQ + TMZ cotreatments. High-performance liquid chromatography assay confirmed the presence of TQ in murine brain tissues. Our findings demonstrate that TQ can effectively cross the BBB and function alone or in combination with TMZ to treat glioblastoma.

Evaluation of Effectiveness and Safety of Microcin C7 in Weaned Piglets.

The effects and safety of dietary supplementation with Microcin C7 (C7) were evaluated in 216 weaned piglets. The pigs were given a control corn−soybean meal basal diet or C7 diet (control diet supplemented with 250, 500, 750, 1000, or 5000 mg C7/kg diets). Compared with the control group, the 500 mg/kg C7 supplementation group had better intestinal morphological indicators (p < 0.05), which may help maintain intestinal epithelial function and increase the growth performance (p < 0.05) and apparent total tract digestibility (p < 0.05). The diarrhea indexes of the 250, 500, and 750 mg/kg groups were significantly lower than that of the control group at 0−28 d (p < 0.05), and the 500 mg/kg group had the lowest diarrhea indexes (linear and quadratic, p < 0.05). A comprehensive analysis showed that microbial structure was significantly correlated with the degree of diarrhea, and the diarrhea-alleviating effect of C7 may be related to its selective regulation of specific microbial taxa. The 250 and 500 mg/kg C7 supplementation also significantly improved several immune indices of piglets (p < 0.05). Compared with the control diet, 5000 mg/kg C7 supplementation had no significant adverse effect on all parameters. Overall, the 250−500 mg/kg dose had the best effect, and the highest dose (5000 mg/kg) posed no toxicity risk. Therefore, C7 appears safe for use as an alternative to antibiotic growth promoters in weaned piglets.

Compromised Hindgut Microbial Digestion, Rather Than Chemical Digestion in the Foregut, Leads to Decreased Nutrient Digestibility in Pigs Fed Low-Protein Diets.

Background: Reduced nutrient digestibility due to low-protein (LP) diets occurring in the foregut or hindgut of pigs remains unclear. Methods: Growing barrows (21.7 ± 1.7 kg) were allotted into LP and high-protein (HP) diet treatments. Ileal digesta and feces were collected for in vitro cross-fermentation and microbial sequencing, and cross-feeding assessed nutrient digestibility. Results: No difference in foregut digesta flora and nutrient digestibility between treatments was observed. LP diet caused decreased total tract digestibility of dry matter (DM), organic matter (OM), gross energy (GE), neutral detergent fiber (NDF), and acid detergent fiber (ADF) compared with the HP diet (p < 0.05). The fermentation broth from LP diet-fed pigs induced less full fermentation digestion of DM, OM, crude protein, and GE than HP broth (p < 0.05). Additionally, LP broth fermentation presented lower fermentation gas and short-chain fatty acids (SCFAs) generation than HP group (p < 0.05). This situation above may be related to decreased abundances of Lachnospiraceae, Eubacterium_eligens_group, Roseburia, and Ruminococcaceae_UCG-009, which can efficiently ferment nutrients to produce SCFA. Conclusions: Change in the flora caused compromise in hindgut microbial fermentation digestion leads to decreased total tract nutrient digestibility in pigs fed an LP diet.

Bright tunable luminescence of Sb3+ doping in zero-dimensional lead-free halide Cs3ZnCl5 perovskite crystals.

Lead-free zero-dimensional (0D) perovskite nanocrystals (NCs) with isolated octahedral structures have attracted considerable attention due to their unique photoelectric properties, such as highly efficient emissions with broadband features. A series of phosphors composed of Sb3+-doped 0D perovskite crystals Cs3ZnCl5 with wavelength-tunable emission spectra have been obtained using a facile recrystallization method at room temperature in air. By controlling the doping concentration of Sb3+ in Cs3ZnCl5 lattice, bright emissions from red to orange have been achieved under excitation at 320 nm due to the expansion of the crystal lattice, and the emission excited at 275 nm is bluish-white, spanning the full visible region. Inductively coupled plasma emission spectrometry (ICP) demonstrates the Sb3+ substitutes for Zn2+ rather than Cs+ due to the similar charges and ionic radii. The luminescence performance of phosphor Cs3ZnCl5:Sb3+ can be improved obviously by replacing 3 mol% of Cs+ with Rb+ or K+ due to the further distortion of the crystal lattice. The present approach allows the synthesis of large-scale emissive lead-free 0D perovskites activated by Sb3+ with tunable luminescence color.

Microbiota Transplantation in an Antibiotic-Induced Bacterial Depletion Mouse Model: Reproducible Establishment, Analysis, and Application.

The fecal bacteria transplantation (FMT) technique is indispensable when exploring the pathogenesis and potential treatments for microbiota-related diseases. For FMT clinical treatments, there are already systematic guidelines for donor selection, fecal bacterial separation, FMT frequency, and infusion methods. However, only a few studies have demonstrated the use of standardized FMT procedures for animal models used in theoretical research, creating difficulties for many new researchers in this field. In the present paper, we provide a brief overview of FMT and discuss its contribution to the current understanding of disease mechanisms that relate to microbiota. This protocol can be used to generate a commonly used FMT mouse model and provides a literature reference of customizable steps.

Free Amino Acid-Enriched Diets Containing Rapidly but Not Slowly Digested Carbohydrate Promote Amino Acid Absorption from Intestine and Net Fluxes across Skeletal Muscle of Pigs.

BACKGROUND: The approach to matching appropriate carbohydrates alongside free amino acids to achieve optimal muscle growth remains unclear. OBJECTIVES: We investigated whether the consumption of a diet containing rapidly digested carbohydrate and free amino acids can enhance intestinal absorption and muscular uptake of amino acids in pigs. METHOD: Twelve barrows (28 kg; 11 wk old) with catheters installed in the portal vein, mesenteric vein, femoral artery, and femoral vein were randomly assigned to consume 1 of 2 free amino acid-enriched diets (3.34%) containing rapidly [waxy corn starch (WCS)] or slowly [pea starch (PS)] digested carbohydrate for 27 d. Blood was collected to determine the fluxes of plasma glucose and amino acids across the portal vein and the hindlimb muscle. Dietary in vitro carbohydrate digestive rates were also determined. Data were analyzed using repeated-measures (time × group) ANOVA. RESULTS: Carbohydrate in vitro cumulative digestibility at 30 and 240 min was 69.00% and 95.25% for WCS and 23.25% and 81.15% for PS, respectively. The animal experiment presented WCS increased individual amino acids (lysine, 0.67 compared with 0.53 mmol/min; threonine, 0.40 compared with 0.29 mmol/min; isoleucine, 0.33 compared with 0.22 mmol/min; glutamate, 0.51 compared with 0.35 mmol/min; and proline, 0.51 compared with 0.27 mmol/min), essential amino acid (EAA; 3.26 compared with 2.65 mmol/min), and branched-chain amino acid (BCAA; 0.86 compared with 0.65 mmol/min) fluxes across the portal vein during 8 h postprandial, as well as individual amino acids (isoleucine, 0.08 compared with 0.02 mmol/min; leucine, 0.06 compared with 0.02 mmol/min; and glutamine, 0.44 compared with 0.25 mmol/min), EAA (0.50 compared with 0.21 mmol/min), and BCAA (0.17 compared with 0.06 mmol/min) net fluxes across the hindlimb muscle during 8 h postprandial compared with PS (P < 0.05). CONCLUSIONS: A diet containing rapidly digested carbohydrate and free amino acids can promote intestinal absorption and net fluxes across hindlimb muscle of amino acids in pigs.

A Novel Approach to Calculate the Spatial-Temporal Correlation for Traffic Flow Based on the Structure of Urban Road Networks and Traffic Dynamic Theory.

Determining the spatial-temporal correlation (STC) between roads can help clarify the operation characteristics of road traffic. Moreover, this correlation affects the utilization quality of traffic data in related research fields. Therefore, it is of significance to provide more reasonable correlation information for other research, such as in traffic speed prediction. Most of the traditional correlation calculation methods for traffic are based on only statistical theory. These methods are simple, but their ability to explain the actual phenomenon is limited due to the lack of consideration of the actual traffic operation characteristics. Therefore, to provide more reasonable correlation information between roads, this paper analysed the influence mechanism of urban traffic based on the traffic dynamic model, and two parameters, traffic complete influence time and traffic correlation strength, were proposed to bring physical meaning to the calculation of STC. Then, an improved calculation model of the STC between different roads considering the adjacency between roads was proposed in this paper. Finally, this paper verified this method against two common traditional methods through different experiments. The verification results show that the calculation method proposed in this paper has better interpretability for the STC between different roads and can better reveal the internal traffic operation characteristics of the road network.

γ-Linolenic Acid Prevents Lipid Metabolism Disorder in Palmitic Acid-Treated Alpha Mouse Liver-12 Cells by Balancing Autophagy and Apoptosis via the LKB1-AMPK-mTOR Pathway.

Excessive fat deposition is the main character in nonalcoholic fatty liver disease (NAFLD), while γ-linolenic acid (GLA) is a polyunsaturated fatty acid that can reduce lipid deposition. This study investigated the effect and regulatory mechanism of GLA (100 µM) on lipid metabolism in alpha mouse liver 12 (AML-12) cells treated by 400 µM palmitic acid (PA). GLA reduced lipid content and increased fatty acid ß oxidation, as indicated by decreasing triglyceride and cholesterol contents and increasing mRNA and protein expressions of CPT1α and PPARα. GLA relieved oxidative stress caused by PA, upregulated mRNA levels of superoxide dismutase and glutathione peroxidase, and decreased reactive oxygen species content. GLA reduced apoptosis, as indicated by decreases in the BAX/BCL2 expression level and apoptosis percentage. GLA activated autophagy, autophagosome-lysosome fusion, and LKB1-AMPK-mTOR signaling and upregulated mRNA and protein expressions of Beclin-1, autophagy-related 5, and liver kinase B1 (LKB1). These effects of GLA on lipid metabolism disorders of PA-treated hepatocytes were reversed by autophagy inhibitor 3MA and AMPK inhibitor compound C, confirming our conclusions. Overall, GLA can protect AML-12 cells from lipid metabolism disorder caused by PA via balancing autophagy and apoptosis mediated by the LKB1-AMPK-mTOR pathway. Consequently, GLA, as a dietary supplement, can help to prevent and treat NAFLD by regulating lipid metabolism and autophagy.

[Plasma metabonomics study of ischemic cerebral apoplexy rats treated with Tongsaimai pellets].

OBJECTIVE: To observe abnormal metabolic changes caused by ischemic cerebral apoplexy and the regulating action of Tongsaimai pellets on abnormal metabolism by analyzing the change of small molecules in plasma of ischemic cerebral apoplexy rat. To find the potential biomarkers, and to explore metabolic mechanisms of Tongsaimai pellets. METHOD: Rat models of middle cerebral artery occlusion was established with electric coagulation, and rats were divided into 4 groups, model group, sham-operation group, Tongsaimai pellets group and positive control group. Tongsaimai pellets and positive control group were orally administrated by 13.2 g x kg(-1) x d(-1) of crude drugs and 32 mg x kg(-1) x d(-1) of Nimodipine respectively, m odel and sham-operation group by equal volume of distilled water for a week. Plasma of model and sham-operation group were collected, and plasma of Tongsaimai pellets and positive control group were collected on the 1st, 3rd , 7th day after administration. Endogenous metabolites of four groups were determined with GC-MS. Partial least squares discriminant analysis (PLS-DA) was applied to analyze multivariate data and set up model, and T-test was used in significant statistical analysis. RESULT: Compared with sham-operation group rats, pyruvic acid, taurine and hydroxyproline obviously increased in model group rats, while lactic acid, glyceric acid, aminomalonic acid, fructose, tryptophan and leucine significantly decreased, so these metabolites were potential metabolic biomarkers. These endogenous metabolites except taurine got restoration in Tongsaimai group rats. CONCLUSION: Abnormal metabolite level in plasma can be certainly recovered by Tongsaimai pellets, and the treatment of Tongsaimai pellets can be connected with the regulation of related metabolic pathways.