Glucose Concentration in Regulating Induced Pluripotent Stem Cells Differentiation Toward Insulin-Producing Cells.

The generation of insulin-producing cells from human-induced pluripotent stem cells holds great potential for diabetes modeling and treatment. However, existing protocols typically involve incubating cells with un-physiologically high concentrations of glucose, which often fail to generate fully functional IPCs. Here, we investigated the influence of high (20 mM) versus low (5.5 mM) glucose concentrations on IPCs differentiation in three hiPSC lines. In two hiPSC lines that were unable to differentiate to IPCs sufficiently, we found that high glucose during differentiation leads to a shortage of NKX6.1+ cells that have co-expression with PDX1 due to insufficient NKX6.1 gene activation, thus further reducing differentiation efficiency. Furthermore, high glucose during differentiation weakened mitochondrial respiration ability. In the third iPSC line, which is IPC differentiation amenable, glucose concentrations did not affect the PDX1/NKX6.1 expression and differentiation efficiency. In addition, glucose-stimulated insulin secretion was only seen in the differentiation under a high glucose condition. These IPCs have higher KATP channel activity and were linked to sufficient ABCC8 gene expression under a high glucose condition. These data suggest high glucose concentration during IPC differentiation is necessary to generate functional IPCs. However, in cell lines that were IPC differentiation unamenable, high glucose could worsen the situation.

Atorvastatin treatment ameliorates cardiac function and remodeling induced by isoproterenol attack through mitigation of ferroptosis.

Ferroptosis has been identified as an important role in damaged heart. Meanwhile, statin therapy has been reported to be beneficial for the treatment of heart failure(HF) under different conditions. However, the beneficial effects of statin treatment on regulation of ferroptosis in failing heart is unveiled. The aim of this study is to explore the protective efficacy of atorvastatin against the ferroptosis related signaling pathway in isoproterenol(ISO)-induced HF. We found that ATV and ferrostatin-1(Fer-1,as a positive control) significantly improved ISO-decreased cell viability and cell survival by reducing oxidative stress and Fe2+-dependent lipid peroxidation in H9C2 cells. Additionally, ISO triggered marked ferritinophagy accompanied by up-regulating protein levels of LC3BII,NCOA4 and Beclin1 and down-regulating protein levels of P62 and FTH1 in damaged cells, which nevertheless was significantly blocked by administration of ATV and these results were in parallel with the results obtained after 3-methyadenine(3-MA) treatment. Consistently, C57BL/6J mice were used in used in this study and administered 5 mg/kg/day ISO for 2 weeks to simulate cardiac injury. 20 mg/kg/day ATV treatment for 2 weeks simultaneously markedly improved cardiac dysfunction and remodeling induced by ISO attack. ATV showed significantly protective effects through suppressing the activation of ferroptosis related signaling, as evidenced by decreasing the mRNA levels of PTGS2(a marker of ferroptosis), contents of malonaldehyde and protein levels of NOX4 and increasing the contents of glutathione(GSH), the ratio of GSH/GSSG and protein levels of GPX4 and SLC7A11. Moreover, ISO evidently triggered degradation of FTH1 in failing heart. However, ATV significantly prevented these changes in damaged heart. Overall, these results reveal atorvastatin suppresses ferroptosis and exhibits protective effect on failing myocardium of mice after ISO insult though inhibiting ferritinophagy-mediated ferroptosis, which might be a potential therapeutic strategy in the prevention of ISO-associated cardiomyopathy.

Long-term atorvastatin or the combination of atorvastatin and nicotinamide ameliorate insulin resistance and left ventricular diastolic dysfunction in a murine model of obesity.

Current studies aimed at investigating the association between atorvastatin therapy and insulin resistance (IR) appear to be controversial. IR is considered to be an important contributor to inducing cardiac dysfunction through multiple signals. The paradoxical cardiotoxicity of atorvastatin reported under different conditions suggests that the association between atorvastatin treatment, insulin resistance and cardiac function should be clarified further. In this study, C57BL/6 J male mice were fed a high-fat diet (HD) or standard chow diet (SD) for 12 weeks and subsequently randomly divided into four groups: the SD-Control (SD-C) and HD-Control (HD-C) groups treated with saline for 10 months and the HD-A and HD-A + N groups treated with atorvastatin (20 mg/kg/day) alone or atorvastatin combined with nicotinamide (NAM, 1 g/kg/day) for 10 months. Although no significant changes in systolic function and structure were observed between the four groups of mice at an age of 46 or 58 weeks, respectively, long-term treatment with atorvastatin alone or atorvastatin and NAM combination significantly retarded the HD-induced IR and diastolic dysfunction and attenuated both cardiac and hepatic fibrosis in obese mice possibly by regulating the cleavage of osteopontin and then controlling profibrotic activity. Changes in cardiac function and structure were similar between the HD-A and HD-A + N groups; however, mice in the HD-A + N group exhibited better glucose control and marked reduction in body weight and hepatic lipid accumulation. Thus, these results suggest that long-term treatment with atorvastatin or the combination of atorvastatin and nicotinamide may be alternative therapies due to their beneficial effects on IR and diastolic function.

Microencapsulation of Bacillus megaterium NCT-2 and its effect on remediation of secondary salinization soil.

Aim: To prolong the shelf life of Bacillus megaterium NCT-2 by preparing microcapsules through spray drying, and evaluate their efficiency in secondary salinisation soil remediation.Methods: The wall material and spray drying conditions were optimised. Morphological characteristics of microcapsule were measured, and soil remediation effects were tested under field conditions.Results: A relatively higher survival rate of B. megaterium microcapsule was obtained with 1:1 of chitosan/maltodextrin (w/w) when spray drying was performed at 150.0 °C, with the feed flow rates of 800 mL h-1 and 1000 mL h-1, respectively. The span value of 0.93 ± 0.01 was obtained under above conditions. Microcapsule survival rate was 64.09 ± 0.12% after 6 months of storage. Moreover, microcapsule successfully decreased NO3- and EC value in strongly saline soil by 46.5 ± 1.48% and 45.2 ± 1.51%, respectively.Conclusion: Bacillus megaterium NCT-2 microcapsules have application potential in the remediation of secondary salinisation soil.

miR-144/451 represses the LKB1/AMPK/mTOR pathway to promote red cell precursor survival during recovery from acute anemia.

The microRNAs miR-144 and -451 are encoded by a bicistronic gene that is strongly induced during red blood cell formation (erythropoiesis). Ablation of the miR-144/451 gene in mice causes mild anemia under baseline conditions. Here we show that miR-144/451-/- erythroblasts exhibit increased apoptosis during recovery from acute anemia. Mechanistically, miR-144/451 depletion increases the expression of the miR-451 target mRNA Cab39, which encodes a co-factor for the serine-threonine kinase LKB1. During erythropoietic stress, miR-144/451-/- erythroblasts exhibit abnormally increased Cab39 protein, which activates LKB1 and its downstream AMPK/mTOR effector pathway. Suppression of this pathway via drugs or shRNAs enhances survival of the mutant erythroblasts. Thus, miR-144/451 facilitates recovery from acute anemia by repressing Cab39/AMPK/mTOR. Our findings suggest that miR-144/451 is a key protector of erythroblasts during pathological states associated with dramatically increased erythropoietic demand, including acute blood loss and hemolytic anemia.

Global end-diastolic volume index vs CVP goal-directed fluid resuscitation for COPD patients with septic shock: a randomized controlled trial.

PURPOSE: This study aimed to investigate the clinical effects of early goal-directed therapy according to the global end-diastolic volume index (GEDI) on chronic obstructive pulmonary disease (COPD) patients with septic shock. METHODS: A total of 71 COPD patients with septic shock were randomly assigned to 2 groups. In the control group (n = 37), fluid resuscitation was performed based on the central venous pressure. In the study group (n = 34), fluid resuscitation was performed until GEDI reached 800 mL/m2. The following indices were observed for the 2 groups: 6- and 24-hour fluid volumes, norepinephrine dosage, 24-hour blood lactate clearance rate, duration of mechanical ventilation, intensive care unit (ICU) length of stay, ICU mortality, and 90-day survival rate. RESULTS: At both 6- and 24-hour measurements, the fluid volume was lower and norepinephrine dosage was higher in the control group than in the study group (P < .05). The blood lactate clearance rate was lower, the duration of mechanical ventilation was longer, and the length of stay in the ICU was longer in the control group than in the study group (P < .05). No significant difference in mortality or 90-day survival rate was found between the 2 groups. CONCLUSIONS: The GEDI goal-directed fluid resuscitation shows better clinical effects than that shown by central venous pressure for COPD patients with septic shock; however, it cannot reduce the mortality rate.

Circulating tumor cells in breast cancer beyond the genotype of primary tumor for tailored therapy.

Although TNM staging based on tumor, node lymph status and metastasis status-is the most widely used method in the clinic to classify breast cancer (BC) and assess prognosis, it offers limited information for different BC subgroups. Circulating tumor cells (CTCs) are regarded as minimal residual disease and are proven to have a strong relationship with BC. Detection of ≥5 CTCs per 7.5 mL in peripheral blood predicts poor prognosis in metastatic BC irrespective of other clinical parameters, whereas, in early-stage BC, detection of CK19(+) CTCs are also associated with poor prognosis. Increasing data and clinical trials show that CTCs can improve prognostic accuracy and help tailor treatment for patients with BC. However, heterogeneous CTCs in the process of an epithelial-mesenchymal transition (EMT) in BC makes it a challenge to detect these rare cells. Moreover, the genotypic and phenotypic features of CTCs are different from primary BC tumors. Molecular analysis of CTCs in BC may benefit patients by identifying those amenable to tailored therapy. We propose that CTCs should be used alongside the TNM staging system and the genotype of primary tumor to guide tailored BC diagnosis and treatment.

LRP1 modulates the microglial immune response via regulation of JNK and NF-κB signaling pathways.

BACKGROUND: Neuroinflammation is characterized by microglial activation and the increased levels of cytokines and chemokines in the central nervous system (CNS). Recent evidence has implicated both beneficial and toxic roles of microglia when over-activated upon nerve injury or in neurodegenerative diseases, including Alzheimer's disease (AD). The low-density lipoprotein receptor-related protein 1 (LRP1) is a major receptor for apolipoprotein E (apoE) and amyloid-ß (Aß), which play critical roles in AD pathogenesis. LRP1 regulates inflammatory responses in peripheral tissues by modulating the release of inflammatory cytokines and phagocytosis. However, the roles of LRP1 in brain innate immunity and neuroinflammation remain unclear. METHODS: In this study, we determined whether LRP1 modulates microglial activation by knocking down Lrp1 in mouse primary microglia. LRP1-related functions in microglia were also assessed in the presence of LRP1 antagonist, the receptor-associated protein (RAP). The effects on the production of inflammatory cytokines were measured by quantitative real-time PCR (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA). Potential involvement of specific signaling pathways in LRP1-regulated functions including mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB) were assessed using specific inhibitors. RESULTS: We found that knocking down of Lrp1 in mouse primary microglia led to the activation of both c-Jun N-terminal kinase (JNK) and NF-κB pathways with corresponding enhanced sensitivity to lipopolysaccharide (LPS) in the production of pro-inflammatory cytokines. Similar effects were observed when microglia were treated with LRP1 antagonist RAP. In addition, treatment with pro-inflammatory stimuli suppressed Lrp1 expression in microglia. Interestingly, NF-κB inhibitor not only suppressed the production of cytokines induced by the knockdown of Lrp1 but also restored the down-regulated expression of Lrp1 by LPS. CONCLUSIONS: Our study uncovers that LRP1 suppresses microglial activation by modulating JNK and NF-κB signaling pathways. Given that dysregulation of LRP1 has been associated with AD pathogenesis, our work reveals a critical regulatory mechanism of microglial activation by LRP1 that could be associated with other AD-related pathways thus further nominating LRP1 as a potential disease-modifying target for the treatment of AD.

Expression and prognostic value of miR-92a in patients with gastric cancer.

MicroRNA (miR)-92 expression is often aberrant in human cancers. However, its expression in gastric carcinoma and its relation to clinicopathological features and prognosis are unclear.Tissue microarrays were constructed from 180 patients with gastric cancer (GC), who were undergoing radical resection. MiR-92a expression was detected using miRNA-locked nucleic acid in situ hybridization, and its correlation with clinicopathological features and overall survival was analyzed. MiR-92a expression was decreased in 13.9 % (25/180) of GC, increased in 81.1 % (146/180), and unchanged in 5.0 % (9/180), compared with paracancerous normal tissue (P < 0.001). Univariate analysis showed that high miR-92a expression, tumor stage, tumor status, node status, and tumor size were significant negative prognostic predictors for overall survival in patients with GC (P < 0.001, P < 0.001, P = 0.008, P < 0.001, and P = 0.001, respectively). High miR-92a expression still remained a significant predictor of shorter survival in stage II (n = 56, P = 0.001) and stage III (n = 92, P = 0.009) GC. Multivariate regression analysis demonstrated that tumor status (hazard ratio [HR], 3.10; 95 % confidence interval [CI], 1.51-6.37; P = 0.002), stage (HR, 3.54; 95 % CI, 1.65-7.63; P = 0.000), lymph node metastasis (HR, 2.83; 95 % CI, 1.88-4.28; P = 0.000), high expression of miR-92a (HR, 2.94; 95 % CI, 2.01-4.31; P = 0.000), and tumor size (HR, 2.34; 95 % CI, 1.45-3.79; P = 0.002) predicted shorter OS.High expression of miR-92a compared with adjacent normal tissues was associated with shorter OS. MiR-92a may thus be useful for evaluating prognosis and may provide a novel treatment target in patients with GC.