Design and synthesis of 9-phenanthranilamide derivatives and the study of anti-inflammatory, antioxidant and neuroprotective activities.

Oxidative stress and a series of excessive inflammatory responses are major obstacles to neurological functional recovery after ischemic stroke. In this study, we synthesized several novel 9-phenanthranilamide derivatives and evaluated their anti-inflammatory and antioxidant activities. Among the initially screened compounds, most could strongly inhibi lipopolysaccharide (LPS)-stimulated production of IL-1ß, IL-6 and TNF-α in microglial cells. Additionally, compounds 8b, 8q, 8r and 8s significantly inhibited the production of NO, and they also had dose-dependent protective effects on PC12 neuronal cells induced by H2O2. The antineuroinflammatory effects of 8r and 8s were associated with the downregulation of LPS-induced inflammatory mediators of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and both compounds inhibited the NF-κB signaling pathway. Further examinations showed that 8s had a significant neuroprotective effect on rats with middle cerebral artery occlusion (MCAO). It decreased the infarct volume and the neurological deficit score. Overall, our results suggested that compound 8s might be a promising agent for stroke treatment.

Discovery of Coixol Derivatives as Potent Anti-inflammatory Agents.

Coixol, a derivative of 2-benzoxazolinone extracted from coix (Coix lachryma-jobi L. var. ma-yuen Stapf), has demonstrated promising anti-inflammatory activity and low cytotoxicity. In this study, 26 coixol derivatives were designed and synthesized by hybridization with cinnamic acid to identify new anti-inflammatory agents. The anti-inflammatory activities of the derivatives were screened using LPS-induced overexpression of nitric oxide (NO) in RAW264.7 macrophages. On the basis of the screening results, compounds containing furan (9c) or nitrofuran (9j) moieties displayed more pronounced activity than coixol and celecoxib. Mechanistic investigations revealed that 9c and 9j suppressed the expression of induced nitric oxide synthase (iNOS), tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1ß, which was associated with the inhibition of the nuclear factor (NF)-κB signaling pathway. In vivo studies confirmed the anti-inflammatory activity of 9c and 9j in a xylene-induced mice auricles edema model. The preliminary in vitro and in vivo research findings suggest that 9c and 9j have the potential to be developed as anti-inflammatory agents.

Design and synthesis of novel indole and indazole-piperazine pyrimidine derivatives with anti-inflammatory and neuroprotective activities for ischemic stroke treatment.

Microglia-mediated neuroinflammation plays an important role in ischemic stroke (IS). In this work, a series of novel indole and indazole-piperazine pyrimidine derivatives with anti-neuroinflammatory and neuroprotective activities were designed and synthesized for treatment of IS. Among these compounds, 5j displayed the most attractive cytoprotective effect against oxygen-glucose deprivation/reoxygenation (OGD/R)-induced damage in BV2 cells. Meanwhile, it significantly ameliorated the release of inflammatory mediators, including tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), IL-6, nitric oxide (NO) and prostaglandin E2 (PGE2), from lipopolysaccharide (LPS)-induced BV2 cells. Moreover, 5j can decrease the release of TNF-α and IL-1ß form LPS-induced mouse brain neuroinflammation model. As a potent inhibitor against both cyclooxygenase-2 (COX-2, IC50 = 92.54 nM) and 5-lipoxygenase (5-LOX, IC50 = 41.86 nM), 5j inhibited the M1 phenotype polarization of microglia and promoted the M2 phenotype polarization of microglia. Additionally, 5j exhibited remarkable neuroprotection in middle cerebral artery occlusion (MCAO) rats by reducing their infarct volumes and neurological deficit scores. In conclusion, 5j has the potential for the treatment of stroke as an anti-inflammatory and neuroprotective agent.

Temperature-Dependent Photoluminescence of Manganese Halide with Tetrahedron Structure in Anti-Perovskites.

The temperature-dependent photoluminescence (PL) properties of an anti-perovskite [MnBr4]BrCs3 sample in the temperature range of 78-500 K are studied in the present work. This material exhibits unique performance which is different from a typical perovskite. Experiments showed that from room temperature to 78 K, the luminous intensity increased as the temperature decreased. From room temperature to 500 K, the photoluminescence intensity gradually decreased with increasing temperature. Experiments with varying temperatures repeatedly showed that the emission wavelength was very stable. Based on the above-mentioned phenomenon of the changing photoluminescence under different temperatures, the mechanism is deduced from the temperature-dependent characteristics of excitons, and the experimental results are explained on the basis of the types of excitons with different energy levels and different recombination rates involved in the steady-state PL process. The results show that in the measured temperature range of 78-500 K, the steady-state PL of [MnBr4]BrCs3 had three excitons with different energy levels and recombination rates participating. The involved excitons with the highest energy level not only had a high radiative recombination rate, but a high non-radiative recombination rate as well. The excitons at the second-highest energy level had a similar radiative recombination rate to the lowest energy level excitons and a had high non-radiative recombination rate. These excitons made the photoluminescence gradually decrease with increasing temperature. This may be the reason for this material's high photoluminescence efficiency and low electroluminescence efficiency.

The effect of sodium carboxymethyl starch with high degree of substitution on defecation.

Sodium carboxymethyl starch (CMS-Na), a kind of food additive with high degree of substitution, is also known as a prebiotic. The aim of this study was to determine the effect of CMS-Na on defecation. Constipated mouse model was prepared by loperamide. Normal rats were also used in the study. Short-chain fatty acids in rat feces were detected by gas chromatography. The bacterial communities in rat feces were identified by 16S rDNA gene sequencing. 5-hydroxytryptamine (5-HT) and tryptophan hydroxylase 1 (Tph1) were measured by ELISA. The results showed that CMS-Na increased the fecal granule counts and intestinal propulsion rate in constipated mice. The contents of water, acetic acid, propionic acid and n-butyrate in feces, Tph1 in colon and 5-HT in serum of rats were increased. In addition, CMS-Na shortened the colonic transport time in rats. The 16S rDNA gene sequencing results indicated that CMS-Na increased the relative abundance of Alloprevotella and decreased the proportion of Lactobacillus. However, the biodiversity of the normal intestinal flora was not altered. In conclusion, CMS-Na can promote defecation in constipated mice. The mechanism may be related to the regulation of Alloprevotella and Lactobacillus in colon, the increase of short-chain fatty acids, and the promotion of the synthesis of Tph1 and 5-HT.

Age differences in the pulmonary and vascular pathophysiologic processes after long-term real-time exposure to particulate matter in rats.

Existing experimental data do not sufficiently explain which pathophysiologic processes are involved in different age of rats exposed to long-term particulate matter. This study explored the pulmonary and cardiovascular effects of long-term PM2.5 and PM10 exposure in juvenile, adult and senescent rats. Tail cuff plethysmography, whole-body plethysmographic system, myograph, enzyme-linked immunosorbent assay, and inductively coupled plasma-mass spectrometry were used to detect the blood pressure, lung function, endothelium-dependent relaxation, inflammatory cytokines and heavy metals, respectively. The exposure time was from November, 2017 to October, 2018, and the average concentrations of PM2.5 and PM10 were 78.7 and 128.2 µg/m3, respectively. Compared with the filtered air group, the body weight and survival rate in PM2.5 and PM10 exposure group were significantly decreased, and the survival rate of senescent exposed rats was only 30%. PM2.5 and PM10 exposure increased the blood pressure, elevated the levels of serum and bronchoalveolar lavage fluid inflammatory factors, and the senescent exposed rats showed an earlier rising trend in blood pressure and inflammatory factors than those of juvenile and adult exposed rats. Long-term PM2.5 and PM10 exposure could destroy intrapulmonary and small resistance arteries endothelial function, causing vasodilation disorders. PM2.5 and PM10 exposure caused particulate matter to accumulate in the lungs. Additionally, PM2.5 and PM10 exposure could also cause accumulation of cadmium (Cd) and lead in the liver, and chromium and Cd in the kidney. In conclusion, ambient PM2.5 and PM10 exposure induced particulate matter to accumulate in the body, caused severe pulmonary and vascular disorders, and demonstrated age-associated differences.

Chronic real-time particulate matter exposure causes rat pulmonary arteriole hyperresponsiveness and remodeling: The role of ETBR-ERK1/2 signaling.

Exposure to air pollution is associated with the incidence of respiratory diseases. The present study evaluated the pulmonary vascular system injury by chronic real-time particulate matter (PM10) exposure and investigated the underlying mechanisms. Rats were exposed to PM10 or filtered air for 2 to 4 months using a whole body exposure system, and intraperitoneally injected with the MEK1/2 inhibitor U0126. Right heart catheterization and myography were performed to detect lung function and pulmonary vascular reactivity, respectively. Western blotting, qRT-PCR, enzyme-linked immunosorbent assay and histological analyses were used to detect the effects and mechanisms by which PM10 exposure-induced pulmonary vascular dysfunction. Functional experiment results showed that PM10 exposure increased the pulmonary artery pressure of rats and caused endothelin B receptor (ETBR)-mediated pulmonary arteriole hyperreactivity. U0126 significantly rescued these pathological changes. PM10 exposure upregulated the contractile ETBR of pulmonary arteriolar smooth muscle, and damaged pulmonary artery endothelial cells to induce the release of more endothelin 1 (ET-1). The upregulated ETBR bound to increased ET-1 induced pulmonary arteriolar hyperresponsiveness and remodeling. U0126 inhibited the PM10 exposure-induced upregulation of ETBR in pulmonary arteriole, ETBR-mediated pulmonary arterial hyperresponsiveness and vascular remodeling. In conclusion, chronic real-time particulate matter exposure can activate the ERK1/2 signaling, thereby inducing the upregulation of contractile ETBR in pulmonary arteriole, which may be involved in pulmonary arteriole hyperresponsiveness and remodeling in rats. These findings provide new mechanistic evidence of PM10 exposure-induced respiratory diseases, and a new possible target for treatment.

F10, a new camptothecin derivative, was identified as a new orally-bioavailable, potent antitumor agent.

Topoisomerases are interesting targets for drug discovery. In the present study, we attached saturated carbon atoms to the 10-position of camptothecin and synthesized 10 new camptothecin derivatives from 10-HCPT or SN-38. The activities of new compounds were evaluated both in vitro and in vivo. The most promising compound F10, 7-ethyl-10-(2-oxo-2-(piperidin-1-yl)ethoxy)camptothecin, inhibited cancer cells growth with the IC50 of 0.002, 0.003, 0.011 and 0.081 µM on Raji, HCT116, A549 and Lovo cells, respectively. Meanwhile, oral administration of F10 remarkably suppressed the HCT116-xenograft tumor growth in the nude-mice model at the dosage of 0.5, 2.0 and 8.0 mg/kg in vivo. Intraperitoneal administration of F10 can completely inhibit Raji-xenograft tumor growth in established NPG mouse model at 2.0 and 4.0 mg/kg. In addition, the minimum lethal doses of F10 and SN-38 in mice by intravenous administration were 80 and 40 mg/kg (or 0.155, 0.102 mmol/kg), respectively. The solubility of F10 reached 9.86 µg/mL in a buffer solution of pH 4.5. The oral bioavailability of F10 achieved 22.4% in mice. The molecular docking model revealed that F10 can interact with topoisomerase I-DNA complex. Our findings indicate that F10 is a new orally-oavailable antitumor agent with potent anticancer effect. Furthermore, attaching a ring hydrophobic moiety to the 10-position of camptothecin provides a favorable approach in the optimization of camptothecin.

Isolation and identification of tiger parvovirus in captive siberian tigers and phylogenetic analysis of VP2 gene.

To better understand the prevalence and molecular epidemiology of parvovirus, this study reports the isolation and characterization of a tiger parvovirus (TPV) named CHJL-Siberian Tiger-01/2017 from a captive Siberian tiger in Jilin Province, China. A phylogenetic tree based on the full-length VP2 nucleotide sequence was constructed using the isolated strain in this study and 56 reference strains. The results showed that all the parvoviruses can be grouped into two large branches: the canine parvovirus (CPV) branch and the feline parvovirus (FPV) branch. FPV strains comprised TPVs, FPVs, blue fox parvoviruses (BFPVs), mink enteritis viruses (MEVs), and raccoon feline parvoviruses (RFPVs), and CPV strains comprised CPVs and raccoon dog parvoviruses (RDPVs). RFPVs are also often very closely related to those sampled from other carnivorous species, and raccoons may represent conduits for parvovirus transmission to other hosts. The results of amino acid changes in the VP2 protein of the isolated strain showed that amino acid Ile 101 was mutated to Thr (I 101T). Taken together, a field TPV strain CHJL-Siberian Tiger-01/2017 was isolated, which may be suitable for future studies on FPV infection, replication and vaccine development. This study provided new important findings about the evolution of parvovirus infection in tigers.

Isolation and identification of a variant subtype G 2b porcine epidemic diarrhea virus and S gene sequence characteristic.

Porcine epidemic diarrhea (PED) which is caused by porcine epidemic diarrhea virus (PEDV), is an intestinal communicable disease. In recent years, though pigs have been immunized with the vaccines in pig farms, PED still broke out and caused severe economic losses to the swine industry in the northeast China. In this study, the sample was positive for PEDV variant strains via the nano-nest PCR. The strain was successfully isolated from positive samples and was serially passaged in Vero-E6 cells. In addition, the strain was identified via electron microscopy observation, indirect immunofluorescence assay and infection experiment in newborn piglets and named PEDV CH/JLDH/2016 strain (Accession No. MF346935). Phylogenetic analysis of the S gene showed that the CH/JLDH/2016 strain was clustered into G2b subgroup. Comparing with the CV777 vaccine strain, amino acid sequence analysis of CH/JLDH/2016 strain showed that 15 nucleotides were inserted and 9 were absent in S gene, whose amino acid sequence it educed insertions of 5 amino acids(58NQGX61 and 145N) and absences of 3 amino acids(164RD165 and 1204Y). Our strain, in the SS2 epitope have no amino acid, variant while in SS6 epitope, Y changed into S in 776th amino acid. The results indicated that PEDV G2b variant strains have been emerged in Jilin province. The identification of new types of PEDV variant strains would stimulate the development of effective vaccines for the prevention and control of PED. The novel vaccines that based on these newly identified PEDV variant strains may contribute to the control of PED outbreaks in China.

Adoptive Transfers of CD4+CD25+ Tregs Raise Foxp3 Expression and Alleviate Mouse Enteritis.

CD4+CD25+Foxp3+ Tregs control the immune response and maintain immune homeostasis. This study examined whether Tregs can affect mouse enteritis and the Foxp3 (Forkhead transcription factor) transcriptional pathway. Mouse CD4+CD25+ Treg cells were labelled using CFSE (5,6-carboxyfluorescein diacetate succinimidyl ester) and transferred to enteritis model mice. The mice were randomly divided into an enteritis group, a Treg-infusion group, a Treg-inhibiting group, and a control group. Histopathology, ELISA, flow cytometry, western blot, immunohistochemistry, and immunofluorescence were performed. Our results demonstrated that CD4+CD25+ Tregs were successfully transferred. The disease activity index (DAI) scores in the Tregs-infusion group were lower than those of the enteritis and Tregs-inhibiting groups. The number of goblet cells and inflammatory cells was reduced, and the levels of IL-1ß, TNF-α, NO, and PGE2 were significantly decreased in the Tregs-infusion group compared to those in the enteritis group (p<0.05). The number of CD4+CD25+Foxp3+ Tregs and CD4+IL-17A+ Th17 cells in the mesenteric lymph nodes differed significantly from the enteritis and Tregs-inhibiting groups (p<0.05). There were more Foxp3+ Tregs and Smad3 and NFAT2 infiltrated into the duodenum after adoptive transfer of CD4+CD25+ Tregs, which was a significant difference relative to the enteritis group (p<0.05). This study demonstrated that adoptive transfer of CD4+CD25+ Tregs can decrease mouse enteritis. Foxp3 expression may be improved through the Smad3 and NFAT2 signalling pathways.