Citrus reticulatae pericarpium Extract Decreases the Susceptibility to HFD-Induced Glycolipid Metabolism Disorder in Mice Exposed to Azithromycin in Early Life.

Background: Studies have shown that gut microbe disorder in mice due to early-life antibiotic exposure promotes glycolipid metabolism disorder in adulthood. However, the underlying mechanism remains unclear and there is not yet an effective intervention or treatment for this process. Purpose: The study investigated whether early-life azithromycin (AZT) exposure in mice could promote high-fat diet (HFD)-induced glycolipid metabolism disorder in adulthood. Moreover, the effect of citrus reticulata pericarpium (CRP) extract on glycolipid metabolism disorder via regulation of gut microbiome in mice exposed to antibodies early in life were investigated. Methods and Results: Three-week-old mice were treated with AZT (50 mg/kg/day) via drinking water for two weeks and then were fed a CRP diet (1% CRP extract) for four weeks and an HFD for five weeks. The results showed that early-life AZT exposure promoted HFD-induced glycolipid metabolism disorder, increased the levels of inflammatory factors, promoted the flora metabolism product trimethylamine N-oxide (TMAO), and induced microbial disorder in adult mice. Importantly, CRP extract mitigated these effects. Conclusion: Taken together, these findings suggest that early-life AZT exposure increases the susceptibility to HFD-induced glycolipid metabolism disorder in adult mice, and CRP extract can decrease this susceptibility by regulating gut microbiome.

Dingxin recipe alleviates atherosclerosis injury in ApoE-knockout mice via downregulation of visfatin expression and inhibition of the visfatin-induced inflammatory response.

OBJECTIVE: To further elucidate the mechanism underlying the anti-atherosclerotic effect of Dingxin recipe (DXR). METHODS: Fifty 6-week-old male ApoE-/- mice were randomly divided into the following groups: model, simvastatin (5 mg·kg－1·d－1), DXR low-dose (9.30 g·kg－1·d－1), DXR middle-dose (18.59 g·kg－1·d－1) and DXR high-dose (37.18 g·kg－1·d－1) (n = 10). Ten male C57BL/6J mice were used as the control group. All ApoE-/- mice were fed a high-fat diet (HFD) and the control mice received a common diet. After HFD for 12 weeks, the mice were treated with DXR or simvastatin for another 12 weeks. The expression of inflammatory cytokines and visfatin was determined in serum and atherosclerotic lesions by enzyme-linked immunosorbent assay. Visfatin expression was also assessed in aortic atherosclerotic plaques. Cultured vessel endothelial cells (VECs) were pretreated with DXR sera prior to visfatin. The effects of DXR were analyzed to elucidate its protective mechanism against visfatin-induced inflammation in VECs. RESULTS: DXR regulated blood lipids and reduced tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), intercellular adhesion molecules-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and visfatin expression in ApoE-/- mice, particularly at the higher doses. The areas of atherosclerotic lesions in the DXR groups were significantly smaller than those in the model group. DXR alleviated visfatin-induced VEC injury via downregulation of TNF-α, IL-6, ICAM-1 and VCAM-1 through mitogen-activated protein kinase pathways. CONCLUSION: DXR alleviated atherosclerosis injury via downregulation of visfatin expression and inhibition of the visfatin-induced inflammatory response in VECs.

Formation potential of nine nitrosamines from corresponding secondary amines by chloramination.

Nitrosamines, a group of emerging disinfection by-products (DBPs) in drinking water, have recently caused significant concern because of their higher carcinogenic potential than that of currently regulated DBPs. In this study, the formation of nine representative nitrosamines by chloramination of their corresponding secondary amines was investigated under various conditions. All nine nitrosamines were detected in the corresponding reaction solutions, which confirmed that all the investigated secondary amines were the potential precursors of corresponding nitrosamines. The molar yields of nitrosamines from the corresponding secondary amines were quite different, depending on the structural characteristics of the secondary amines. The maximum molar yields for the formation of all nine nitrosamines occurred in the pH range of 7.0-9.0 and at the Cl/N molar ratio of 0.7 for chloramines, suggesting that monochloramine and unprotonated secondary amines may play a major role in the formation of nitrosamines. The molar yields of nitrosamines also exhibited a moderate upward tendency with rising temperature, but no consistent correlation was observed between the formation of nitrosamine and the initial concentrations of secondary amines and chloramines. The results of this study could be useful for devising strategies for controlling the formation of nitrosamines during the disinfection processes of drinking water.

Formation and cytotoxicity of a new disinfection by-product (DBP) phenazine by chloramination of water containing diphenylamine.

Disinfection by-products (DBPs) in drinking water have caused worldwide concern due to their potential carcinogenic effects. The formation of phenazine from diphenylamine (DPhA) chloramination was studied and its cytotoxicities for two human cancer cells were also investigated. Phenazine was detected synchronously with the consumption of DPhA by chloramination, which further confirmed that the new DBP phenazine can be produced along with N-nitrosodiphenylamine (NDPhA) from DPhA chloramination. The formation of phenazine had a maximum molar yield with solution pH increasing from 5.0 to 9.0, with phenazine as the main product for DPhA chloramination at lower pH, but higher pH favored the formation of NDPhA. Thus, solution pH is the key factor in controlling the formation of phenazine and NDPhA. Both the initial DPhA and chloramine concentrations did not show a significant effect on the molar yields of phenazine, although increasing the chloramine concentration could speed up the reaction rate of DPhA with chloramines. The cytotoxicity assays showed that phenazine had significant cell-specific toxicity towards T24 (bladder cancer cell lines) and HepG2 (hepatic tumor cell lines) cells with IC50 values of 0.50 and 2.04 mmol/L, respectively, and T24 cells being more sensitive to phenazine than HepG2 cells. The IC50 values of phenazine, DPhA, and NDPhA for T24 cells were of the same order of magnitude and the cytotoxicity of phenazine for T24 cells was slightly lower than that of NDPhA (IC50, 0.16 mmol/L), suggesting that phenazine in drinking water may have an adverse effect on human health.

Solubilization properties of polycyclic aromatic hydrocarbons by saponin, a plant-derived biosurfactant.

The enhanced solubilization of polycyclic aromatic hydrocarbons (PAHs) by saponin, a plant-derived non-ionic biosurfactant, was investigated. The results indicated that the solubilization capabilities of saponin for PAHs were greater than some representative synthetic non-ionic surfactants and showed strong dependence on solution pH and ionic strength. The molar solubilization ratio (MSR) of saponin for phenanthrene was about 3-6 times of those of the synthetic non-ionic surfactants, and decreased by about 70% with the increase of solution pH from 4.0 to 8.0, but increased by approximately 1 times with NaCl concentration increased from 0.01 to 1.0 M. Heavy metal ions can enhance saponin solubilization for phenanthrene and the corresponding MSR values increased by about 25% with the presence of 0.01 M of Cd2+ or Zn2+. Saponin is more effective in enhancing PAHs solubilization than synthetic non-ionic surfactants and has potential application in removing organic pollutants from contaminated soils.