Growth differentiation factor 7 pretreatment enhances the therapeutic capacity of bone marrow-derived mesenchymal stromal cells against cerebral ischemia-reperfusion injury.

Bone marrow-derived mesenchymal stem cells (BMSCs) transplantation is a promising therapeutic strategy for cerebral ischemia/reperfusion (I/R) injury; however, the clinical outcome is barely satisfactory and demands further improvement. The present study aimed to investigate whether preconditioning of BMSCs by recombinant human growth differentiation factor 7 (rhGDF7) could enhance its therapeutic capacity against cerebral I/R injury. Mouse BMSCs and primary neurons were co-cultured and exposed to oxygen glucose deprivation/reperfusion (OGD/R) stimulation. To investigate the role of exosomal microRNA-369-3p (miR-369-3p), inhibitors, RNAi and the miR-369-3p antagomir were used. Meanwhile, mice were intravenously injected with rhGDF7-preconditioned BMSCs and then received cerebral I/R surgery. Markers of inflammation, oxidative stress and neural damage were evaluated. To inhibit AMP-activated protein kinase (AMPK), compound C was used in vivo and in vitro. Compared with cell-free transwell or vehicle-preconditioned BMSCs, rhGDF7-preconditioned BMSCs significantly prevented OGD/R-induced inflammation, oxidative stress and neural damage in vitro. Meanwhile, rhGDF7-preconditioned BMSCs could prevent I/R-induced cerebral inflammation and oxidative stress in vivo. Mechanistically, rhGDF7 preconditioning significantly increased exosomal miR-369-3p expression in BMSCs and then transferred exosomal miR-369-3p to primary neurons, where it bound to phosphodiesterase 4 D (Pde4d) 3'-UTR and downregulated PDE4D expression, thereby preventing I/R-induced inflammation, oxidative stress and neural damage through activating AMPK pathway. Our study identify GDF7 pretreatment as a promising adjuvant reagent to improve the therapeutic potency of BMSCs for cerebral I/R injury and ischemic stroke.

Association of Body Iron Metabolism with Type 2 Diabetes Mellitus in Chinese Women of Childbearing Age: Results from the China Adult Chronic Disease and Nutrition Surveillance (2015).

High iron stores have been reported to be associated with type 2 diabetes mellitus (T2DM). However, evidence for the associations of iron metabolism with T2DM is inconsistent, and whether there is a threshold effect remains controversial. In the present study, we aimed to examine the associations between various iron biomarkers and the risk of T2DM as well as impaired glucose metabolism (IGM) and hyperglycemia in Chinese women of childbearing age. A total of 1145 women were divided into three groups (normal blood glucose metabolism group; IGM group; T2DM group). Biomarkers of iron metabolism (serum ferritin (SF), transferrin, soluble transferrin receptor (sTfR), transferrin saturation, serum iron, total body iron, and sTfR-to-lgferritin index) were measured. After adjusting for various confounding risk factors, SF and sTfR were positively associated with the risk of IGM (fourth vs. first quartile: SF odds ratio (OR) = 1.93 (95% CI 1.17-3.20) and sTfR OR = 3.08 (95% CI 1.84-5.14)) and T2DM (SF OR = 2.39 (95% CI 1.40-4.06) and sTfR OR = 3.84 (95% CI 2.53-5.83)). There was a nonlinear relationship between SF and risk of T2DM and hyperglycemia (p for nonlinearity < 0.01). Our findings suggested that SF and sTfR could be independent predictors of T2DM risk.

Clinical value of the detection of EGFR gene mutations in pleural effusion cell blocks among patients with non-small-cell lung cancer.

OBJECTIVE: To evaluate the clinical value of epidermal growth factor receptor (EGFR) detection in pleural effusion cell blocks among patients with non-small-cell lung cancer (NSCLC). METHODS: From July 2016 to September 2018, EGFR gene mutations in 40 lung tumor tissue samples and pleural fluid samples from NSCLC patients in Jinhua Municipal Central Hospital were assessed by the amplification refractory mutation system method. The EGFR results of the two types of samples were compared using the paired Chi-square test, and the mutation positive rates in EGFR exons 18, 19, 20 and 21 were compared between the two types of specimens using the four-grid Chi-square test. RESULTS: Among the 40 tissue samples and pleural effusion samples, 21 and 18 cases of EGFR mutations were detected, respectively, and the mutation positive rates were 52.5% and 45%, respectively. The κ value of the consistency test of the two specimens was 0.851. There were no significant differences in the mutation positive rates in EGFR exons 18, 19, 20, and 21 between the two types of specimens. CONCLUSION: The EGFR results of pleural fluid and tissue samples were in good agreement. Therefore, we can use pleural fluid samples to detect EGFR mutations to guide tyrosine kinase inhibitor treatment for NSCLC patients in whom tumor tissue samples cannot be obtained.

Significant association of urinary alpha-1-microglobulin compared to urinary neutrophil gelatinase-associated lipocalin with renal insufficiency in patients with type 2 diabetes.

AIM: Various studies have reported that urinary neutrophil gelatinase-associated lipocalin (NGAL), an indicator of tubular damage, may be an effective biomarker of renal impairment in patients with diabetes. This study aimed to compare the ability of urinary alpha-1-microglobulin (a traditional tubular damage marker) with NGAL for evaluating renal insufficiency in patients with type-2 diabetes. METHODS: Urinary albumin-to-creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR) were used to determine whether 513 participants with type-2 diabetes had renal dysfunction. Urinary alpha-1-microglobulin-to-creatinine ratio (A1MCR) and NGAL-to-creatinine ratio (NCR) were calculated. RESULTS: Although both A1MCR and NCR were significantly higher among participants with renal insufficiency than among participants without renal damage, the difference in A1MCR values between participants with and without renal insufficiency was relatively greater than the difference in NCR values, especially among the male subjects. The correlation of ACR or eGFR with A1MCR was stronger than that of ACR or eGFR with NCR. A1MCR showed a good capability for detecting renal dysfunction (area under the curve = 0.80), its cut-off value was 14.82 mg/g, corresponding to 71.4% sensitivity and 73.1% specificity. The diagnostic efficiency of A1MCR was significantly higher than that of NCR. CONCLUSION: The results indicated that the traditional tubular damage marker A1MCR was more significantly associated with renal insufficiency defined by ACR and/or eGFR and may have a higher diagnostic efficiency compared with the efficiency of NCR in patients with type-2 diabetes.

Acrylamide induces HepG2 cell proliferation through upregulation of miR-21 expression.

Acrylamide, a potential carcinogen, exists in carbohydrate-rich foods cooked at a high temperature. It has been reported that acrylamide can cause DNA damage and cytotoxicity. The present study aimed to investigate the potential mechanism of human hepatocarcinoma HepG2 cell proliferation induced by acrylamide and to explore the antagonistic effects of a natural polyphenol curcumin against acrylamide via miR-21. The results indicated that acrylamide (≤100 µmol/L) significantly increased HepG2 cell proliferation and miR-21 expression. In addition, acrylamide reduced the PTEN expression in protein level, while induced the expressions of p-AKT, EGFR and cyclin D1. The PI3K/AKT inhibitor decreased p-AKT protein expression and inhibited the proliferation of HepG2 cells. In addition, curcumin effectively reduced acrylamide-induced HepG2 cell proliferation and induced apoptosis through the expression of miR-21. In conclusion, the results showed that acrylamide increased HepG2 cell proliferation via upregulating miR-21 expression, which may be a new target for the treatment and prevention of cancer.

Association between dietary carbohydrate intake, glycemic index and glycemic load, and risk of gastric cancer.

PURPOSE: The association between dietary carbohydrate intake, glycemic index (GI) and glycemic load (GL), and risk of gastric cancer (GC) has been investigated by many studies. However, the results of these studies were controversial. The aim of our study was to systematically assess this issue. METHODS: PUBMED and EMBASE were searched up to March 2015, and either a fixed- or a random-effects model was adopted to estimate overall relative risks (RRs). Dose-response, meta-regression, subgroup, and publication bias analyses were applied. RESULTS: Twenty-six studies with approximately 540,000 participants were finally included in this meta-analysis. High level of dietary carbohydrate intake (pooled RR 1.17, 95 % CI 0.91-1.50), GI (pooled RR 1.17, 95 % CI 0.80-1.69), and GL (pooled RR 1.06, 95 % CI 0.90-1.26) were all nonsignificantly associated with incidence of GC. In addition, no significant dose-response relationship was observed between carbohydrate intake, GI and GL, and the risk of GC. However, further subgroup analyses based on gender and geographic region suggested a significant association between higher carbohydrate intake (pooled RR 1.52, 95 % CI 1.10-2.08), GL (pooled RR 1.41, 95 % CI 1.04-1.92), and GC risk in males subgroup, and between higher carbohydrate intake (pooled RR 1.69, 95 % CI 1.36-2.09) and GC risk in Asian studies. CONCLUSIONS: No significant association was found between dietary carbohydrate intake, GI and GL, and risk of GC. However, significantly positive association was observed in the males subgroup and Asian studies.

Interleukin-1B 31 C>T polymorphism combined with Helicobacter pylori-modified gastric cancer susceptibility: evidence from 37 studies.

Gastric cancer is one of the most common malignancies worldwide. Interleukin-1-beta (IL-1ß) is a pro-inflammatory cytokine and potent inhibitor of gastric acid secretion. Some studies provided evidence of the association between IL-1B 31 polymorphism and gastric cancer risk while other studies did not. Therefore, we conducted a comprehensive meta-analysis to reassess the association. A systematic literature search of the PubMed and EMBASE databases identified 37 studies with 6108 cases and 8980 controls for this meta-analysis. The crude odd ratios (ORs) and the 95% confidence intervals (CIs) were calculated to evaluate the strength of the association. Meta-regression was used to determine the major source of heterogeneity across the studies. The pooled analysis did not suggest the significant association of IL-1B 31 C>T polymorphism with gastric cancer risk. Stratified analysis was performed by ethnicity, source of control, genotype method, and indicated a significantly increased gastric cancer risk associated with IL-1B 31T variant in the population-based subgroup (heterozygous model: OR = 1.22, 95% CI = 1.03-1.45). Moreover, stratified analysis by Helicobacter pylori infection status indicated that IL-1B 31 polymorphism increased gastric cancer risk in infection-positive subgroup (homozygous model: OR = 1.35, 95% CI = 1.02-1.78; heterozygous model: OR = 1.31, 95% CI = 1.04-1.66; recessive model: OR = 1.29, 95% CI = 1.04-1.61). The study suggested that IL-1B 31 polymorphism might confer susceptibility to gastric cancer in the presence of H. pylori infection, indicating a gene-environment interaction in gastric carcinogenesis.

PFOS Disturbs BDNF-ERK-CREB Signalling in Association with Increased MicroRNA-22 in SH-SY5Y Cells.

Perfluorooctane sulfonate (PFOS), a ubiquitous environmental pollutant, is neurotoxic to mammalian species. However, the underlying mechanism of its neurotoxicity was unclear. We hypothesized that PFOS suppresses BDNF expression to produce its neurotoxic effects by inhibiting the ERK-CREB pathway. SH-SY5Y human neuroblastoma cells were exposed to various concentrations of PFOS to examine the role of the BDNF-ERK-CREB signalling pathway in PFOS-induced apoptosis and cytotoxicity. Furthermore, to ascertain the mechanism by which PFOS reduces BDNF signalling, we examined the expression levels of miR-16 and miR-22, which potentially regulate BDNF mRNA translation at the posttranscriptional level. Results indicated that PFOS significantly decreased cell viability and induced apoptosis in SH-SY5Y cells. In addition, BDNF and pERK protein levels decreased after PFOS treatment; however, pCREB protein levels were significantly elevated in PFOS treated groups. TrkB protein expression increased in the 10 µM and 50 µM PFOS groups and significantly decreased in the 100 µM PFOS group. Our results demonstrated that PFOS exposure decreased miR-16 expression and increased miR-22 expression, which may represent a possible mechanism by which PFOS decreases BDNF protein levels. PFOS may inhibit BDNF-ERK-CREB signalling by increasing miR-22 levels, which may, in part, explain the mechanism of PFOS neurotoxicity.

Curcumin Reactivates Silenced Tumor Suppressor Gene RARß by Reducing DNA Methylation.

Reactivation of tumor suppressor genes by nontoxic bioactive food component represents a promising strategy for cancer chemoprevention. Retinoic acid receptor ß (RARß), one member of the RAR receptor family, is considered as a tumor suppressor. Reduced expression of RARß has been reported in lung cancer and other solid tumors. DNA hypermethylation of the promoter region of RARß is a major mechanism for its silencing in tumors. Recently, curcumin has been considered as a potential DNA methyltransferase inhibitor. Herein, we demonstrated that curcumin significantly elevate RARß expression at the mRNA and protein levels in tested cancer cells. Additionally, curcumin decreased RARß promoter methylation in lung cancer A549 and H460 cells. Mechanistic study demonstrated that curcumin was able to downregulate the mRNA levels of DNMT3b. In a lung cancer xenograft node mice model, curcumin exhibited protective effect against weight loss because of tumor burden. Tumor growth was strongly repressed by curcumin treatment. As the results from in vitro, RARß mRNA were increased and DNMT3b mRNA were decreased by curcumin treatment compared with the mice in control group. Altogether, this study reveals a novel molecular mechanism of curcumin as a chemo-preventive agent for lung cancer through reactivation of RARß.

Mechanism of Dose-Dependent Regulation of UBE1L by Polyphenols in Human Bronchial Epithelial Cells.

Ubiquitin activating enzyme E1-like (UBE1L) is the activating enzyme for ISG15ylation (ISG15, interferon stimulated gene 15). UBE1L is thought to be a candidate tumor suppressor gene and has positive activity against stress responses such as viral infections. Both type I interferon and retinoic acid are known to induce UBE1L expression. However, the molecular mechanism of UBE1L regulation is unclear. Here, the effect of several chemopreventive polyphenols on UBE1L expression in human bronchial epithelial cells (Beas-2B) was investigated. Lower concentrations of curcumin, (-)-epigallocatechin-3-gallate (EGCG) and resveratrol upregulated UBE1L, while high concentrations of curcumin, EGCG and resveratrol downregulated UBE1L levels. Interestingly, curcumin, EGCG and resveratrol diminished intracellular reactive oxygen species (ROS) at lower concentrations but generated ROS at higher concentrations. The antioxidant N-acetylcysteine (NAC) increased UBE1L protein levels, while pro-oxidants such as hydrogen peroxide and tert-butyl hydroperoxide (tBHP) decreased UBE1L protein levels, indicating that the intracellular redox status is associated with UBE1L expression. Kinase inhibitors were used to examine the contribution of mitogen-activated protein kinase (MAPK) activity to the polyphenol-regulated UBE1L. Only the inhibition of c-Jun N-terminal kinase (JNK) significantly reduced UBE1L expression. Knockdown of nuclear factor erythroid-2 related factor-2 (Nrf2) caused a concomitant decrease in UBE1L protein levels. It is concluded from the above mentioned results that JNK/Nrf2 signal pathway is involved in the regulation of UBE1L via intracellular ROS status when cells came in contact with polyphenols.

Curcumin and (-)-epigallocatechin-3-gallate attenuate acrylamide-induced proliferation in HepG2 cells.

Acrylamide, a proven rodent carcinogen, is present in carbohydrate-rich food heated at high temperatures. It can be metabolized into glycidamide mainly by cytochrome P450 2E1 (CYP2E1). The fact that acrylamide is a potential carcinogen to human-beings draws public attention recently. This study aimed to elucidate the effect of acrylamide at low doses on proliferation of HepG2 cells, and to test whether the two well-studied chemopreventive agents, curcumin and (-)-epigallocatechin-3-gallate (EGCG), would have antagonistic effects against acrylamide. The results showed that lower concentration of acrylamide (⩽100µM) significantly increased the proliferation of HepG2 cells, but not of the other cancer cells (MDA-231, HeLa, A549, and PC-3). Only in HepG2 cells, low concentration of acrylamide was able to induce CYP2E1 expression significantly. Knockdown of CYP2E1 restrained acrylamide to increase viability of HepG2 cells. In addition, acrylamide raised expression of epidermal growth factor receptor (EGFR), cyclin D1 and nuclear factor-κB (NF-κB), which contributed to cell proliferation. Both curcumin and EGCG effectively reduced acrylamide-induced proliferation, as well as protein expression of CYP2E1, EGFR, cyclin D1 and NF-κB. All these results suggest that low concentration of acrylamide may contribute to progression of hepatocellular carcinoma (HCC). Curcumin or EGCG could prevent acrylamide triggering this effect.