Intrahepatic Cholestasis of Pregnancy Increases Inflammatory Susceptibility in Neonatal Offspring by Modulating Gut Microbiota

Intrahepatic cholestasis of pregnancy (ICP) is a liver disease of pregnancy that is characterized by increased bile acid levels in maternal serum. Studies have shown that cholestatic pregnancy can result in long-term metabolic disturbances in the offspring. However, how ICP shapes the offspring’s immunity and predisposition to inflammatory disorders at an early stage is unknown. In this study, we investigated the effect of maternal cholestasis on neonatal offspring metabolism and immune function. We compared 71 neonates with ICP mothers and 63 neonates with healthy mothers and found that the incidence of jaundice and infection was significantly higher in ICP offspring. Maternal serum total bile acid level was associated with blood cell counts in full-term ICP offspring. In animal experiments, a compensatory activation of hepatic and ileal farnesoid X receptor (FXR) and altered gut microbiota in the first week were found in ICP offspring. We also investigated lipopolysaccharide (LPS)-induced inflammatory responses in neonatal rats and found that ICP offspring were more susceptible to inflammation. To understand the correlation between congenital abnormal FXR activation and tissue immunity dysregulation, we assessed the effects of the FXR agonist GW4064 and FXR antagonist E/Z-GS in ICP offspring after LPS exposure. The expression of several pro-inflammatory cytokines significantly decreased after treatment with E/Z-GS but increased after treatment with GW4064. Treatment with the probiotic Lactobacillus rhamnosus LRX01 that inhibits FXR expression in the ileum reduced susceptibility to LPS exposure in ICP offspring. The current study indicated that cholestatic pregnancy may increase the susceptibility of the offspring to inflammation by altering bile acid metabolism and gut microbiota at an early stage. We suggest that supplementation with Lactobacillus rhamnosus LRX01, which inhibits FXR expression in the ileum, may improve intestinal immunity in ICP offspring.

Synthesis and receptor dependent 4D-QSAR studies of 4,5-dihydro-1,3,4-oxadiazole derivatives targeting cannabinoid receptor

Cannabinoid receptor has been shown to be overexpressed in various types of cancers, especially non-small cell lung cancer. As a result, it could be used as novel target for anticancer treatments. Because receptor-dependent 4D-QSAR generates conformational ensemble profiles of compounds by molecular dynamics simulations at the binding site of the enzyme, this work describes the synthesis, biological activity evaluation and 4D-QSAR studies of 4,5-dihydro-1,3,4-oxadiazole derivatives targeting cannabinoid receptor. Compared with WIN55,212-2, compound 5 f showed the best antiproliferative activity. The receptor-dependent 4D-QSAR model was generated by multiple linear regression method using QSARINS. Leave-n-out cross-validation and chemical applicability domain were performed to analyse the independent test set and to verify the robustness of the model. The best 4D-QSAR model showed the following statistics: r² = 0.8487, Q²_LOO = 0.7667, Q²_LNO = 0.7524, and r²_Pred = 0.8358.

[The definition of heat-wave based on mortality risk assessment in different regions of China]

Objective: To identify the definition of heat wave based on mortality risk assessment in different regions of China. Methods: Daily mortality (from China Information System for Disease Control and Prevention) and meteorological data (from National Meteorological Information Center in China) from 66 counties with a population of over 200 000 were collected from 2006-2011. With the consideration of climate type and administrative division, China was classified as seven regions. Firstly, distributed lag non-linear model (DLNM) was used to estimate community-specific effects of temperature on non-accidental mortality. Secondly, a multivariate meta-analysis was applied to pool the estimates of community-specific effects to explore the region-specific temperature threshold and the duration for definition of heat wave. Results: We defined regional heat wave of Northeast, North, Northwest, East, Central and Southwest China as being two or more consecutive days with daily mean temperature higher than or equal to the P(64), P(71), P(85), P(67), P(75) and P(77) of warm season (May to October) temperature, respectively, while the thresholds of temperature were 21.6, 23.7, 24.3, 25.7, 28.0 and 25.3 ℃. The heat wave in South China was defined as five or more consecutive days with daily mean temperature higher than or equal to the P(93) (30.4 ℃) of warm season (May to October) temperature. Conclusion: The region-specific definition of heat wave developed in our study may provide local government with the guidance of establishment and implementation of early heat-health response systems to address the negative health outcomes due to heat wave.

[Commuting mode specific exposure to PM(2.5) in urban area of Guangzhou]

Objective: To find the differences in PM(2.5) exposure level in the context of four commuting modes (by walk, bicycle, bus and subway) in Guangzhou. Methods: The PM(2.5) exposure assessment was carried out from January to December 2015 in Guangzhou. PM(2.5) was measured by using SidePak individual dust meter (AM510, TSI Inc. USA) with time interval of 1 minute. Our measurement was taken on Monday, Wednesday, Friday and Sunday in the second week of each month and the samples were collected in the morning (07:00-09:00), afternoon (11:00-13:00) and evening (17:00-19:00). Results: A total of 284 air samples during walking, 281 air samples during bicycle riding, 278 air samples in bus, and 280 air samples in subway were collected. The median PM(2.5) concentrations exposed during walking, during bicycle riding, in bus and in subway were 38.4, 38.6, 23.3 and 24.1 μg/m(3), respectively, which were positive correlated with exposure concentration in fixed surveillance sites. The exposure level was lowest in summer, and highest in winter. The median of one-way exposure level to PM(2.5) from high to low were as follows: 21.0 μg for bicycle riding, 20.1 μg for walking, 5.1 μg for taking bus and 2.6 μg for taking subway. The season and time specific one-way exposure levels to PM(2.5) of four commuting modes were consistent. Conclusions: The exposure level to PM(2.5) was obviously higher during walking and bicycle riding than that in bus and subway. The exposure level to PM(2.5) during walking was higher than that during bicycle riding, in bus and in subway.

[Effectiveness of health education about heat wave hazard prevention in the elderly: a mixed effect model analysis]

Objective: To evaluate the effectiveness of health education about prevention of heat wave hazard in the elderly. Methods: A non-randomized controlled trial was conducted during the summer of 2015 among a sample of residents aged ≥60 years in Panyu district, Guangzhou. Eight intervention measures for heat wave hazard prevention were taken in intervention group for 3 months (from August to October) and in control group no intervention measures were taken. The comparison of intervention effects was conducted between the intervention group and control group with mixed effect model after the collection of related information with same questionnaire. Results: After adjusting of family per capita income, family air-condition availability, alcohol use, disease history and time, the average score of risk awareness in the intervention group increased by 1.62, while it was 0.51 in the control group, the difference was significant (t=2.76, P=0.006). A significant effect was observed in the intervention group on the reduction of hospitalizations due to chronic diseases. The hospitalization rate due to chronic diseases in resent 3 months in the intervention group decreased from 32.39% (46/142) before intervention to 28.87% (41/142) after intervention; while in the control group, it increased from 26.28% (41/156) before intervention to 36.53% (57/156) after intervention. There was no significant difference between the two groups in awareness of knowledge on heat wave hazard prevention and the score of adaptation to heat wave. Conclusion: Health education programs could improve the risk awareness on heat waves, and reduce the hospitalizations due to chronic diseases in the elderly.

Involvement of Src tyrosine kinase and protein kinase C in the expression of macrophage migration inhibitory factor induced by H2O2 in HL-1 mouse cardiac muscle cells

Macrophage migration inhibitory factor (MIF), a pleiotropic cytokine, plays an important role in the pathogenesis of atrial fibrillation; however, the upstream regulation of MIF in atrial myocytes remains unclear. In the present study, we investigated whether and how MIF is regulated in response to the renin-angiotensin system and oxidative stress in atrium myocytes (HL-1 cells). MIF protein and mRNA levels in HL-1 cells were assayed using immunofluorescence, real-time PCR, and Western blot. The result indicated that MIF was expressed in the cytoplasm of HL-1 cells. Hydrogen peroxide (H₂O₂), but not angiotensin II, stimulated MIF expression in HL-1 cells. H₂O₂-induced MIF protein and gene levels increased in a dose-dependent manner and were completely abolished in the presence of catalase. H₂O₂-induced MIF production was completely inhibited by tyrosine kinase inhibitors genistein and PP1, as well as by protein kinase C (PKC) inhibitor GF109203X, suggesting that redox-sensitive MIF production is mediated through tyrosine kinase and PKC-dependent mechanisms in HL-1 cells. These results suggest that MIF is upregulated by HL-1 cells in response to redox stress, probably by the activation of Src and PKC.

Loss of macrophage migration inhibitory factor impairs the growth properties of human HeLa cervical cancer cells

OBJECTIVES

  This study aims to determine the role of macrophage migration inhibitory factor (MIF), a proinflammatory cytokine associated with cell proliferation and tumour growth in vivo.

MATERIALS AND METHODS

  Our team used RNA interference technology to knock down MIF expression in human HeLa cervical cancer cells and to establish a stable cell line lacking MIF function.

RESULTS

  Our results showed that long-term loss of MIF had little effect on cell morphology, but significantly inhibited their population growth and proliferation. The HeLa MIF-knockdown cells retained normal apoptotic signalling pathways in response to TNF-alpha treatment; however, they exhibited unique DNA profiles following doxorubicin treatment, suggesting that MIF may regulate a cell cycle checkpoint upon DNA damage. Our data also showed that knockdown of MIF expression in HeLa cells led to increased cell adhesion and therefore impaired their migratory capacity. More importantly, cells lacking MIF failed to either proliferate in soft agar or form tumours in vivo, when administered to nude mice.

CONCLUSION

  MIF plays a pivotal role in proliferation and tumourigenesis of human HeLa cervical carcinoma cells, and may represent a promising therapeutic target for cancer intervention.

Comparison of approaches for efficient gene silencing induced by microRNA-based short hairpin RNA and indicator gene expression

MicroRNA-based short hairpin RNAs (shRNAs) are natural inducers of RNA interference and have been increasingly used in shRNA expression strategies. In the present study, we compared the efficiencies of exogenous green fluorescence protein (GFP) and endogenous glyceraldehyde-3-phosphate dehydrogenase (GAPDH) knockdown and red fluorescent protein (RFP) indicator expression mediated by three differently designed plasmids. RFP was introduced either at the 5' end, at the 3' end of the human mir155-based target gene (TG) (e.g., GFP or GAPDH) shRNA expression cassette (EC), or at the 3' end of the chimeric intron-containing TG shRNA EC. Comparisons with the control vector showed an obvious reduction of GFP or GAPDH expression with the various shRNA expression plasmids (P < 0.05). When RFP was located at the 5' end or at the 3' end of the TG shRNA EC, RFP expression was low; whereas when RFP was connected with the chimeric intron-containing TG shRNA EC, RFP expression was high. Taken together, this study demonstrated an efficient plasmid design for both TG silencing induced by microRNA-based shRNA and indicator gene expression in vitro.

Fasting early morning rise in peripheral insulin: evidence of the dawn phenomenon in nondiabetes

The dawn phenomenon, a tendency for glucose to rise between 0500 and 0800 h in subjects with diabetes, is also reflected as an increase in insulin required to maintain normoglycemia during closed-loop insulin infusion. Individuals without diabetes have minimal or absent rises in early morning glucose. To test the hypothesis that the absence of early morning glucose increases in subjects without diabetes is due to an increase in insulin levels, we measured insulin levels from 2400 to 0800 h in four male and two female volunteers. Subjects were on an unrestricted diet with three main meals and one bedtime snack at 2100 h. Blood samples were collected continuously in hourly pools by a constant-rate withdrawal pump. We observed the following: (1) hourly integrated concentration of glucose was stable from 2400 to 0800 h (range of mean plasma values, 94.5-97.3 mg/dl), and (2) hourly integrated concentration of insulin increased from the 0300-0400 (4.6 microU/ml) to the 0700-0800-h pool (6.2 microU/ml) (P less than 0.05). The observed increase in insulin in the early morning hours despite stable levels of glucose indicates a temporally increased insulin need in nondiabetic individuals similar to that found in individuals with diabetes. The mechanism underlying this increased insulin need may be similar in diabetes and nondiabetes, with the ensuing rise in glucose being dependent on the availability of compensatory insulin.