Dopamine regulates colonic glial cell-derived neurotrophic factor secretion through cholinergic dependent and independent pathways.

BACKGROUND AND PURPOSE: Glial cell-derived neurotrophic factor (GDNF) maintains gut homeostasis. Dopamine promotes GDNF release in astrocytes. We investigated the regulation by dopamine of colonic GDNF secretion. EXPERIMENTAL APPROACH: D1 receptor knockout (D1 R-/- ) mice, adeno-associated viral 9-short hairpin RNA carrying D2 receptor (AAV9-shD2 R)-treated mice, 6-hydroxydopamine treated (6-OHDA) rats and primary enteric glial cells (EGCs) culture were used. Incubation fluid from colonic submucosal plexus and longitudinal muscle myenteric plexus were collected for GDNF and ACh measurements. KEY RESULTS: D2 receptor-immunoreactivity (IR), but not D1 receptor-IR, was observed on EGCs. Both D1 receptor-IR and D2 receptor-IR were co-localized on cholinergic neurons. Low concentrations of dopamine induced colonic GDNF secretion in a concentration-dependent manner, which was mimicked by the D1 receptor agonist SKF38393, inhibited by TTX and atropine and eliminated in D1 R-/- mice. SKF38393-induced colonic ACh release was absent in D1 R-/- mice. High concentrations of dopamine suppressed colonic GDNF secretion, which was mimicked by the D2 receptor agonist quinpirole, and absent in AAV-shD2 R-treated mice. Quinpirole decreased GDNF secretion by reducing intracellular Ca2+ levels in primary cultured EGCs. Carbachol ( ACh analogue) promoted the release of GDNF. Quinpirole inhibited colonic ACh release, which was eliminated in the AAV9-shD2 R-treated mice. 6-OHDA treated rats with low ACh and high dopamine content showed decreased GDNF content and increased mucosal permeability in the colon. CONCLUSION AND IMPLICATIONS: Low concentrations of dopamine promote colonic GDNF secretion via D1 receptors on cholinergic neurons, whereas high concentrations of dopamine inhibit GDNF secretion via D2 receptors on EGCs and/or cholinergic neurons.

Azonal steatosis correlates with disease severity and poor outcome of nonalcoholic fatty liver disease.

OBJECTIVES: In this study we aimed to assess the clinicopathological characteristics and long-term prognosis of patients with nonalcoholic fatty liver disease (NAFLD) having distinct steatosis distribution patterns. METHODS: Clinicopathological data of 238 individuals with biopsy-confirmed NAFLD were collected. Nonalcoholic steatohepatitis-clinical research network (NASH-CRN) and steatosis, activity and fibrosis (SAF)/fatty liver inhibition of progression (FLIP) algorithm were used. Cumulative incidence of liver-related events (LREs) was compared by Kaplan-Meier analysis. Univariate and multivariate logistic regression analyses were used to identify independent predictors for steatosis distribution. RESULTS: Eligible patients were categorized into three groups based on their steatosis distribution, including azonal steatosis (AS) (62 [26.1%]), perivenular steatosis (PVS) (147 [61.8%]), and the pan-acinar steatosis (PAS) groups (29 [12.1%]). There were significantly higher ballooning grade and disease activity (P < 0.05), more severe fibrosis (P < 0.001), and a higher cumulative incidence of LREs (hazard ratio [HR] 8.0, 95% confidence interval [CI] 2.34-27.35, P < 0.0001) in the AS group than in the PVS and PAS groups after a median of 3.6-year follow-up. Multivariate logistic regression analysis revealed age (odds ratio [OR] 1.11, 95% CI 1.06-1.16, P < 0.001) might be independently associated with AS distribution, and PNPLA3 rs738409 CG/GG genotype (OR 3.36, 95% CI 0.98-11.47, P = 0.053) might also play a role. CONCLUSIONS: AS is associated with more severe disease activity and fibrosis stage in NAFLD, and predisposes toward poor prognosis. Age might be an independent predictor for AS in NAFLD, while PNPLA3 rs738409 CG/GG genotype might also play a role.

Impact of inflammatory factors, hemoglobin A1c, and platelet parameters in gestational diabetes mellitus.

PURPOSE: The aim of this study was to evaluate the relationship among inflammatory cytokines including hypersensitive C-reactive protein (hs-CRP) and interleukin-6 (IL-6), glycated hemoglobin A1c (HbA1c), and platelet distribution width (PDW) in women with gestational diabetes mellitus (GDM). METHODS: Data on 191 pregnant women (96 women with GDM; 95 healthy controls) were extracted from routine prenatal examination records in Nanjing, China. Fasting concentrations of hs-CRP, IL-6, HbA1c, blood cell indices, and glucose at 24-28th gestational weeks were determined. RESULTS: The levels of hs-CRP, IL-6, FPG, PG1h, PG2h, HbA1c, RBC, and PDW significantly were increased (P < 0.05) in GDM group. hs-CRP had a positive correlation with HbA1c and PLT (P < 0.05). The odds ratios of HbA1c and PDW were 7.817 (95% CI 1.921-31.816, P = 0.004) and 1.523 (95% CI 1.158-2.002, P = 0.003), respectively. Furthermore, AUC of the combined diagnosis of GDM including HbA1c, FPG, and PDW reached 0.754, with specificity of 80.0% and sensitivity of 60.4%. CONCLUSION: Our findings support that elevated levels of hs-CRP, IL-6, HbA1c, and PDW at 24-28th gestational weeks even within the conventional normal range, may be implicated in the pathogenesis of GDM and their evaluation should be part of prenatal care routine.

Histological assessment based on liver biopsy: the value and challenges in NASH drug development.

Nonalcoholic steatohepatitis (NASH) is increasingly recognized as a serious disease that can lead to cirrhosis, hepatocellular carcinoma (HCC), and death. However, there is no effective drug to thwart the progression of the disease. Development of new drugs for NASH is an urgent clinical need. Liver biopsy plays a key role in the development of new NASH drugs. Histological findings based on liver biopsy are currently used as the main inclusion criteria and the primary therapeutic endpoint in NASH clinical trials. However, there are inherent challenges in the use of liver biopsy in clinical trials, such as evaluation reliability, sampling error, and invasive nature of the procedure. In this article, we review the advantages and value of liver histopathology based on liver biopsy in clinical trials of new NASH drugs. We also discuss the challenges and limitations of liver biopsy and identify future drug development directions.

Non-obese patients with nonalcoholic fatty liver disease may use a lower liver stiffness cut-off to assess fibrosis stages.

OBJECTIVE: We aimed to estimate the optimal cut-off values of liver stiffness measurement (LSM) for diagnosing and staging fibrosis in non-obese and obese patients with nonalcoholic fatty liver disease (NAFLD). METHODS: NAFLD patients diagnosed by liver biopsy according to the Nonalcoholic Steatohepatitis Clinical Research Network scoring system were enrolled in this study. Non-obesity was defined as a body mass index (BMI) less than 25 kg/m2 . LSM was performed by experienced physicians within 2 weeks before or after liver biopsy. RESULTS: A total of 158 patients were included. Average BMI of the non-obese (n = 68) and obese (n = 90) groups was 23.2 ± 1.6 and 27.9 ± 2.5 kg/m2 , respectively. After adjusted for age, fibrosis stage, steatosis grade and type 2 diabetes mellitus, the obese group had a LSM of 3.522 kPa higher than the non-obese patients (P = 0.003). LSM values of the non-obese patients had a lower trend when stratified by fibrosis stage, especially in cirrhosis (F4; P = 0.021). Applying separate cut-off values for patients with NAFLD in individual fibrosis stage, 5.8 vs 7.5 kPa (≥ F1), 7.6 vs 8.5 kPa (≥ F2), 9.1 vs 11.2 kPa (≥ F3), and 12.5 vs 14.3 kPa (F4), improved their diagnostic odds ratios compared with overall cut-off values. In the non-obese NAFLD group, using a separate cut-off avoided underestimating 9.1% of patients with cirrhosis. CONCLUSIONS: Non-obese NAFLD group had lower LSM than the obese group. Different cut-off values should be used to measure liver fibrosis stage in non-obese and obese NAFLD patients.

NLRP3 Phosphorylation Is an Essential Priming Event for Inflammasome Activation.

Many infections and stress signals can rapidly activate the NLRP3 inflammasome to elicit robust inflammatory responses. This activation requires a priming step, which is thought to be mainly for upregulating NLRP3 transcription. However, recent studies report that the NLRP3 inflammasome can be activated independently of transcription, suggesting that the priming process has unknown essential regulatory steps. Here, we report that JNK1-mediated NLRP3 phosphorylation at S194 is a critical priming event and is essential for NLRP3 inflammasome activation. We show that NLRP3 inflammasome activation is disrupted in NLRP3-S194A knockin mice. JNK1-mediated NLRP3 S194 phosphorylation is critical for NLRP3 deubiquitination and facilitates its self-association and the subsequent inflammasome assembly. Importantly, we demonstrate that blocking S194 phosphorylation prevents NLRP3 inflammasome activation in cryopyrin-associated periodic syndromes (CAPS). Thus, our study reveals a key priming molecular event that is a prerequisite for NLRP3 inflammasome activation. Inhibiting NLRP3 phosphorylation could be an effective treatment for NLRP3-related diseases.

Dry eye and corneal sensitivity after small incision lenticule extraction and femtosecond laser-assisted in situ keratomileusis: a Meta-analysis.

AIM: To assess the corneal sensitivity and the incidences of dry eye after small incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK). METHODS: The Meta-analysis was performed using RevMan 5.3. We searched on PubMed from inception to March 2016. Summary weighted mean difference (WMD) and 95% confidence intervals (CIs) were used to analyze the datum. Random-effects or fixed-effects models were chosen up to between-study heterogeneity. The main outcomes were composed of the Ocular Surface Disease Index (OSDI) scores, tear film break-up time (TBUT), Schirmer Test and corneal sensitivity. RESULTS: Eight eligible studies including 772 eyes (386 in SMILE group and 386 in FS-LASIK group) were identified. The parameters have no significiant difference heterogeneity between SMILE and FS-LASIK group preoperatively. There were significant differences between the two groups in OSDI scores at one and three months postoperatively, in TBUT at one and three months postoperatively, in corneal sensitivity at one week, about one month and three months postoperatively. However, there was no significant difference observed in Schirmer Test at the follow-up periods. CONCLUSION: Compare to FS-LASIK, dry eye and the corneal sensitivity recover better in the SMILE group, in first three months after the surgery.

Steroids as an adjunct for reducing the incidence of proliferative vitreoretinopathy after rhegmatogenous retinal detachment surgery: a systematic review and meta-analysis.

BACKGROUND: This meta-analysis was performed to determine the effectiveness of steroids as an adjunct following rhegmatogenous retinal detachment (RRD) surgery. METHODS: RRD patients with or without proliferative vitreoretinopathy (PVR) were included. The treatment group included patients in whom steroids were used as an adjunct and a control group in which placebo was used. Only randomized controlled trials were included. We searched the main electronic databases and included studies published until July 2014. PVR odds ratio, visual acuity, retinal reattachment rate, and complications were evaluated in three trials. RESULTS: Three randomized controlled trials were included in the meta-analysis. There was no significant difference in the incidence of postoperative PVR between groups (heterogeneity I (2)=48%, P=0.14). However, the incidence of postoperative PVR was lower in the treatment group (I (2)=0%, P<0.0001) than in the control group when a PVR grade C study was excluded. There was no statistically significant difference in postoperative visual acuity between the treatment and control groups (odds ratio -0.18; 95% confidence interval -0.38, 0.02; P=0.08). The two groups had similar results for primary/final retinal reattachment and reoperation rate. There was no significant difference in postoperative intraocular pressure. CONCLUSION: This systematic review demonstrates that steroids may significantly reduce the incidence of postoperative PVR grade B or lower following RRD surgery.

Dysregulation of the miR-324-5p-CUEDC2 axis leads to macrophage dysfunction and is associated with colon cancer.

CUEDC2, a CUE-domain-containing protein, modulates inflammation, but its involvement in tumorigenesis is still poorly understood. Here, we report that CUEDC2 is a key regulator of macrophage function and critical for protection against colitis-associated tumorigenesis. CUEDC2 expression is dramatically upregulated during macrophage differentiation, and CUEDC2 deficiency results in excessive production of proinflammatory cytokines. The level of CUEDC2 in macrophages is modulated by miR- 324-5p. We find that Cuedc2 KO mice are more susceptible to dextran-sodium-sulfate-induced colitis, and macrophage transplantation results suggest that the increased susceptibility results from the dysfunction of macrophages lacking CUEDC2. Furthermore, we find that Cuedc2 KO mice are more prone to colitis-associated cancer. Importantly, CUEDC2 expression is almost undetectable in macrophages in human colon cancer, and this decreased CUEDC2 expression is associated with high levels of interleukin-4 and miR-324-5p. Thus, CUEDC2 plays a crucial role in modulating macrophage function and is associated with both colitis and colon tumorigenesis.