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MQ (l-methionyl-l-glutamic acid), anti-inflammatory dipeptide, is one of the metabolites of monocyte locomotion inhibitory factor, a thermostable pentapeptide secreted by Entamoeba histolytica . Monocyte locomotion inhibitory factor injection has been approved as an investigational drug for the potential neural protection in acute ischemic stroke. This study further investigated the neuroprotective effect of MQ in ischemic brain damage. Ischemia-reperfusion injury of the brain was induced in the rat model by middle cerebral artery occlusion. 2,3,5-triphenyltetrazolium chloride staining assay was used to measure cerebral infarction areas in rats. Laser Doppler measurement instrument was used to detect blood flow changes in the rat model. Nissl staining and NeuN staining were utilized to observe the numbers and structures of neuron cells, and the pathological changes in the brain tissues were examined by hematoxylin-eosin staining. Terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling (TUNEL) staining was used to assess cell apoptosis. The changes in oxidative stress indexes, superoxide dismutase and malondialdehyde (MDA), were measured in serum. Methyl thiazolyl tetrazolium was used to measure the survival rates of PC12 cells. Flow cytometry assessed the apoptosis rates and the levels of reactive oxygen species. Real-time PCR was used to evaluate the mRNA expression levels, and Western blotting was used to analyze the changes in protein levels of p-JNK, Bax, cleaved Caspase3. We revealed that MQ improved neurobehavior, decreased cerebral infarction areas, altered blood flow volume, and the morphology of the cortex and hippocampus. On the other hand, it decreased the apoptosis of cortical neurons and the levels of MDA, and increased the levels of superoxide dismutase. In vitro studies demonstrated that MQ enhanced the cell survival rates and decreased the levels of reactive oxygen species. Compared to the oxygen-glucose deprivation/reperfusion group, the protein and mRNA expressions of p-JNK, Bax, cleaved Caspase3 was decreased significantly. These findings suggested that MQ exerts a neuroprotective effect in cerebral ischemia by blocking apoptosis via the p-JNK/Bax pathway., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhang, Dai, Song, Guo, Deng, Yu, Li and Zhang.)

Purpose: Xanthones demonstrated an array of pharmacological activities via non-covalent DNA interaction and have been widely utilized in new drug research. The introduction of the polar 1,2,3-triazole ring located at the C3-position of xanthone has not been reported thus far., Methods: In the present study, a series of xanthone derivatives were designed, synthesized, and characterized through 1 H NMR, 13 C NMR, and MS. The methyl thiazolyl tetrazolium method was used to evaluate the cytotoxic activity of compounds. Furthermore, the structure-activity relationship and the potential mechanism of target compounds were investigated., Results: The IC 50 showed that the inhibitory activity of 18 target compounds was higher than that of the original xanthone intermediate 4. In particular, compound 1j was the most active agent against A549 cancer cells (IC 50 = 32.4 ± 2.2 μM). Moreover, apoptosis analysis indicated different contributions of early/late apoptosis to cell death for compounds 1h and 1j. The results of Western blotting analysis showed that compound 1j significantly increased the expression of caspase 3, Bax, and c-Jun N-terminal kinase, and regulated p53 to a better healthy state in cancer cells., Conclusion: We synthesized several derivatives of xanthone and evaluated their cytotoxicity. The evidence suggested that compound 1j possessed greater anticancer potential for further evaluations., Competing Interests: The authors declare no conflict of interests in this work., (© 2019 Wu et al.)

In recent years, the treatment of wastewater treatment plant (WWTP) effluent has gained increasing attention. However, researches on the relationships between nitrogen forms and nitrogen removal efficiency are very limited. Based on the fact that the nitrogen forms in the WWTP effluent may vary as the season changes, the nitrogen removal efficiencies of an integrated ecological floating bed (IEFB) was studied under different influent nitrogen forms. In addition, the effects of sediments in the system were also quantified during the experiment. Results showed that the total nitrogen (TN) removal rates of the IEFB were 25.61 ± 5.72% and 60.03 ± 7.00%, respectively, when the main influent nitrogen forms are nitrate and ammonia. The sediments in the system also played vital roles in the removal processes: when the sediments were covered with a polyethylene membrane, the total nitrogen (TN) removal rate of the system dropped from 27.86 ± 5.53% to 14.78 ± 4.97%, and the total phosphorus (TP), from 58.77 ± 6.20% to 33.51 ± 25.52%.

The present study aims to investigate the gastroprotective effect of Brucea javanica oil emulsion (BJOE) in animals. Gastroprotective potential of BJOE was studied on absolute ethanol, aspirin, reserpine and restraint plus water immersion-induced gastric ulcers in mice as well as glacial acetic acid (GAA) and pyloric ligation (PL)-induced gastric ulcers in rats. Except for ulcer scores, total acidity as well as pepsin activity as for the PL-induced gastric ulcer model and ulcer incidence as for the GAA-induced gastric ulcer model were also determined. Histopathological evaluation as for aspirin, reserpine, PL-induced models was conducted. Results showed that BJOE significantly ( P  < 0.05) reduced ulcer index in the mouse and rat models in a dose-dependent manner. It had significant ( P  < 0.05) suppressive effect on total activity of gastric juice as well in PL-induced model. Histopathological examination for the stomach samples confirmed the findings in the aspirin, reserpine or PL-induced gastric lesion models, which showed relatively complete mucosa structure and less inflammation. It is concluded that BJOE could be effective on gastric ulcer in rodents and its gastroprotective activity might be related to antioxidant, anti-inflammatory ability and promote gastric mucus secreted. The results may provide beneficial basis for increasing BJOE's clinical indication in future., (© 2018 Shenyang Pharmaceutical University. Production and hosting by Elsevier B.V.)

Pu-erh tea has become a focus of research due to its reported biological activities, including anti-oxidation, anti-inflammation and anti-immunosenescence. The present study was performed to evaluate the potential gastroprotective function of Pu-erh tea extracts against ethanol-induced gastric mucosal damage in rats. Sprague Dawley rats were randomly divided into seven groups: A normal control, a model control, a cimetidine (0.08 g/kg) group, three Pu-erh tea extracts groups (low, moderate and high-dose; 0.50, 1.00 and 1.50 g/kg, respectively, and a green tea powder (1.00 g/kg) group. The normal and model groups were pre-treated with distilled water while the other groups were respectively administered cimetidine, Pu-erh tea extracts and green tea powder for 14 days. Then, absolute ethanol was orally administered to the rats of all groups excluding the normal controls. The effects of the pretreatments on gastric mucosal injury were evaluated by gross assessment of gastric lesions, examination of histopathology and determination of myeloperoxidase (MPO) activity and asymmetric arginine (ADMA) concentration in gastric mucosal homogenate. Pre-treatment with cimetidine or Pu-erh tea extracts markedly suppressed the formation of ethanol-induced gastric lesions. Furthermore, clear decreases in MPO activity and ADMA concentration in the gastric mucosal homogenate were observed following pretreatment with cimetidine or Pu-erh tea extracts. The anti-gastric ulcer activity of green tea was less than that of Pu-erh tea. Overall, these effects of Pu-erh tea extracts may be due to potential functions in protecting the gastric mucus layer and suppressing inflammation.