[Association Between Plasma Adiponectin and Risk of Breast Cancer by Molecular Subtypes].

OBJECTIVE: To explore the relationships between plasma adiponectin levels and risk of breast cancer by molecular subtype. METHODS: A case-control study including 437 histopathologic confirmed primary breast cancer cases and 469 healthy female controls was conducted between April 2014 and May 2015. Basic information of the participants were collected using a structured questionnaire. Blood samples were collected and the plasma adiponectin levels were measured by enzyme-linked immunosorbent assay (ELASA). Analysis of variance (ANOVA) was used to compare the differences of plasma adiponectin levels among the control group and the breast cancer groups with different molecular subtypes. Multinomial logistic regression was used to investigate the association between plasma adiponectin levels and risk of breast cancer by molecular subtypes. All the statistical analyses were stratified by menopausal status. RESULTS: Among the 437 breast cancer cases, there were 310 Luminal breast cancer cases, 83 HER-2-enriched breast cancer cases and 44 basal-like breast cancer cases. The median (P25, P75) of plasma adiponectin level of the controls was 14.85 (9.69, 21.35) µg/mL. The medians (P25, P75) of plasma adiponectin levels of the cases were 11.74 (8.15, 16.14) µg/mL, 12.02(8.43, 16.96) µg/mL and 12.67(8.25, 17.27) µg/mL for Luminal, HER-2-enriched and basal-like subtype respectively, which were statistically different from the controls (P < 0.001). Multinomial logistic regression showed that, after adjustment for the confounders, the higher levels of plasma adiponectin were associated with the lower risks of pre-menopausal Luminal breast cancer (ORpre-menopausal Luminal=0.50, 95%CI: 0.27-0.92, Ptrend=0.001), post-menopausal Luminal breast cancer (ORpost-menopausal Luminal=0.06, 95%CI: 0.02-0.23, Ptrend < 0.001) and post-menopausal HER-2-enriched breast cancer (ORpost-menopausal HER-2-enriched=0.06, 95%CI: 0.01-0.62, Ptrend=0.001). CONCLUSION: Lower levels of plasma adiponectin may increase the risk of pre-menopausal and post-menopausal Luminal breast cancer and post-menopausal HER-2-enriched breast cancer.

Protective effect of pranlukast on Aß1₋42-induced cognitive deficits associated with downregulation of cysteinyl leukotriene receptor 1.

Deposition of extracellular amyloid-ß (Aß) peptide is one of the pathological hallmarks of Alzheimer's disease (AD). Accumulation of Aß is thought to associate with cognition deficits, neuroinflammation and apoptosis observed in AD. However, effective neuroprotective approaches against Aß neurotoxicity are unavailable. In the present study, we analysed the effects of pranlukast, a selective cysteinyl leukotriene receptor 1 (CysLT1R) antagonist, on the impairment of learning and memory formation induced by Aß and the probable underlying electrophysiological and molecular mechanisms. We found that bilateral intrahippocampal injection of Aß1₋42 resulted in a significant decline of spatial learning and memory of mice in the Morris water maze (MWM) and Y-maze tests, together with a serious depression of in vivo hippocampal long-term potentiation (LTP) in the CA1 region of the mice. Importantly, this treatment caused significant increases in CysLT1R expression and subsequent NF-κB signaling, caspase-3 activation and Bcl-2 downregulation in the hippocampus or prefrontal cortex. Oral administration of pranlukast at 0.4 or 0.8 mg/kg for 4 wk significantly reversed Aß1₋42-induced impairments of cognitive function and hippocampal LTP in mice. Furthermore, pranlukast reversed Aß1₋42-induced CysLT1R upregulation, and markedly suppressed the Aß1₋42-triggered NF-κB pathway, caspase-3 activation and Bcl-2 downregulation in the hippocampus and prefrontal cortex in mice. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay confirmed its presence in the brain after oral administration of pranlukast in mice. These data disclose novel findings about the therapeutic potential of pranlukast, revealing a previously unknown therapeutic possibility to treat memory deficits associated with AD.

Mitochondrial Autophagy and NLRP3 Inflammasome in Pulmonary Tissues from Severe Combined Immunodeficient Mice after Cardiac Arrest and Cardiopulmonary Resuscitation.

BACKGROUND: The incidence of cancer, diabetes, and autoimmune diseases has been increasing. Furthermore, there are more and more patients with solid organ transplants. The survival rate of these immunocompromised individuals is extremely low when they are severely hit-on. In this study, we established cardiac arrest cardiopulmonary resuscitation (CPR) model in severe combined immunodeficient (SCID) mice, analyzed the expression and activation of mitochondrial autophagy and NLRP3 inflammasome/caspase-1, and explored mitochondrial repair and inflammatory injury in immunodeficiency individual during systemic ischemia-reperfusion injury. METHODS: A potassium chloride-induced cardiac arrest model was established in C57BL/6 and nonobese diabetic/SCID (NOD/SCID) mice. One hundred male C57BL/6 mice and 100 male NOD/SCID mice were randomly divided into five groups (control, 2 h post-CPR, 12 h post-CPR, 24 h post-CPR, and 48 h post-CPR). A temporal dynamic view of alveolar epithelial cells, macrophages, and neutrophils from bronchoalveolar lavage fluid (BALF) was obtained using Giemsa staining. Spatial characterization of phenotypic analysis of macrophages in the lung interstitial tissue was analyzed by flow cytometry. The morphological changes of mitochondria 48 h after CPR were studied by transmission electron microscopy and quantified according to the Flameng grading system. Western blotting analysis was used to detect the expression and activation of the markers of mitochondrial autophagy, NLRP3 inflammasome, and caspase-1. RESULTS: (1) In NOD/SCID mice, macrophages were disintegrated in BALF, and many alveolar epithelial cells were shed at 48 h after resuscitation. Compared with C57BL/6 mice, the ratio of macrophages/total cells peaked at 12 h and was significantly higher in NOD/SCID mice (31.17 ± 4.13 vs. 49.69 ± 2.43, t = 14.46, P = 0.001). After 24 h, the results showed a downward trend. Furthermore, a large number of macrophages were disintegrated in the BALF. (2) Mitochondrial autophagy was present in both C57BL/6 and NOD/SCID mice after CPR, but it began late in the NOD/SCID mice. Compared with C57BL/6 mice, phos-ULK1 (Ser327) expression was significantly lower at 2 h and 12 h after CPR (2 h after CPR: 1.88 ± 0.36 vs. 1.12 ± 0.11, t = -1.36, P < 0.01 and 12 h after CPR: 1.52 ± 0.16 vs. 1.05 ± 0.12, t = -0.33, P < 0.01), whereas phos-ULK1 (Ser757) expression was significantly higher at 2 h and 12 h after CPR in NOD/SCID mice (2 h after CPR: 1.28 ± 0.12 vs. 1.69 ± 0.14, t = 1.7, P < 0.01 and 12 h after CPR: 1.33 ± 0.10 vs. 1.94 ± 0.13, t = 2.75, P < 0.01). (3) Furthermore, NLRP3 inflammasome/caspase-1 activation in the pulmonary tissues occurred early and for only a short time in C57BL/6 mice, but this phenomenon was sustained in NOD/SCID mice. The expression of the NLRP3 inflammasome increased modestly in the C57 mice, but the increase was higher in the NOD/SCID mice than in the C57BL/6 mice, especially at 12, 24, 48 h after CPR (48 h after CPR: 1.46 ± 0.13 vs. 2.97 ± 0.19, t = 5.34, P = 0.001). The expression of caspase-1-20 generally followed the same pattern as the NLRP3 inflammasome. CONCLUSIONS: There is a regulatory relationship between the NLRP3 inflammasome and mitochondrial autophagy after CPR in the healthy mice. This regulatory relationship was disturbed in the NOD/SCID mice because the signals for mitochondrial autophagy occurred late, and NLRP3 inflammasome- and caspase-1-dependent cell injury was sustained.

Montelukast targeting the cysteinyl leukotriene receptor 1 ameliorates Aß1-42-induced memory impairment and neuroinflammatory and apoptotic responses in mice.

Montelukast, known as a cysteinyl leukotriene receptor 1 (CysLT1R) antagonist, is currently used for treatment of inflammatory diseases such as asthma. Here, we investigated effects of montelukast on neuroinflammatory, apoptotic responses, and memory performance following intracerebral infusions of amyloid-ß (Aß). The data demonstrated that intracerebroventrical infusions of aggregated Aß1-42 (410 pmol/mouse) produced deficits in learning ability and memory, as evidenced by increase in escape latency during acquisition trials and decreases in exploratory activities in the probe trial in Morris water maze (MWM) task, and by decrease in the number of correct choices and increase in latency to enter the shock-free compartment in Y-maze test, and caused significant increases in pro-inflammatory cytokines such as NF-κB p65, TNF-α and IL-1ß as well as pro-apoptotic molecule caspase-3 activation and anti-apoptotic protein Bcl-2 downregulation in hippocampus and cortex. Interestingly, this treatment resulted in upregulation of protein or mRNA of CysLT1R in both hippocampus and cortex. Blockade of CysLT1R by repeated treatment with montelukast (1 or 2 mg/kg, ig, 4 weeks) reduced Aß1-42-induced CysLT1R expression and also suppressed Aß1-42-induced increments of NF-κB p65, TNF-α, IL-1ß and caspase-3 activation, and Bcl-2 downregulation in the hippocampus and cortex. Correspondingly, montelukast treatment significantly improved Aß1-42-induced memory impairment in mice, but had little effect on normal mice. Our results show that montelukast may ameliorate Aß1-42-induced memory impairment via inhibiting neuroinflammation and apoptosis mediated by CysLT1R signaling, suggesting that CysLT1R antagonism represents a novel treatment strategy for Alzheimer's disease.

PPARγ agonist pioglitazone reverses memory impairment and biochemical changes in a mouse model of type 2 diabetes mellitus.

AIMS: Pioglitazone, known as a peroxisome proliferator-activated receptor γ (PPARγ) agonist, is used to treat type 2 diabetes mellitus (T2DM). T2DM has been associated with reduced performance on numerous domains of cognitive function. Here, we investigated the effects of pioglitazone on memory impairment in a mouse model with defects in insulin sensitivity and secretion, namely high-fat diet (HFD) streptozotocin (STZ)-induced diabetic mice. METHODS: ICR mice were fed with HFD for 4 weeks and then injected with a single low dose of STZ followed by continued HFD feeding for an additional 4 weeks. Pioglitazone (18 mg/kg, 9 mg/kg body weight) was orally administered for 6 weeks once daily. Y-maze test and Morris water maze test (MWM) were employed for testing learning and memory. Serum glucose, serum insulin, serum triglyceride, brain ß-amyloid peptide (Aß), brain ß-site amyloid precursor protein cleaving enzyme (BACE1), brain nuclear factor κB (NF-κB), and brain receptor for advanced glycation end products (RAGE) were also tested. RESULTS: The STZ/HFD diabetic mice, characterized by hyperglycemia, hyperlipemia and hypoinsulinemia, performed poorly on Y-maze and MWM hence reflecting impairment of learning and memory behavior with increases of Aß40/Aß42, BACE1, NF-κB, and RAGE in brain. Treatment of PPARγ agonist, pioglitazone (18 or 9 mg/kg body weight), significantly reversed diabetes-induced impairment of learning and memory behavior, which is involved in decreases of Aß40/Aß42 via inhibition of NF-κB, BACE1 and RAGE in brain as well as attenuation of hyperglycemia, hyperlipemia, and hypoinsulinemia. CONCLUSIONS: It is concluded that PPARγ agonist pioglitazone may be considered as potential pharmacological agents for the management of cognitive dysfunction in T2DM.