Estradiol Prevents High Glucose-Induced β-cell Apoptosis by Decreased BTG2 Expression

Follicular fluid exosomes inhibit expression of BTG2 and promote glucose uptake in granulosa cells by delivering miR-21-5p

Glucose metabolism in granulosa cells (GCs) is essential for follicle development and oocyte maturation. Porcine follicular fluid exosomes promote the proliferation of porcine GCs and the synthesis of steroid hormones. However, their role in regulating glucose uptake in GCs is unclear. The objective of this study was to elucidate the effects of porcine follicular fluid exosomes on glucose uptake in porcine GCs and the intrinsic mechanisms involved. First, transcriptome sequencing revealed that glucose metabolism-related pathways were altered in GCs treated with follicular fluid exosomes. Next, in vitro culture experiments showed that glucose uptake was increased and the IRS1/AKT signaling pathway was activated in GCs after treatment with follicular fluid exosomes. Finally, miRNA sequencing of follicular fluid exosomes revealed that miR-21-5p was the most abundant miRNA. Subsequent investigations indicated that miR-21-5p promoted glucose uptake in GCs by targeting BTG2, which activated the IRS1/AKT signaling pathway. In conclusion, the findings of this study indicate that porcine follicular fluid exosomes promote glucose uptake in porcine GCs by delivering miR-21-5p, which inhibits the expression of BTG2, activating the IRS1/AKT signaling pathway.

Human Pancreatic α-Cell Heterogeneity and Trajectory Inference Analysis Using Integrated Single Cell- and Single Nucleus-RNA Sequencing Platforms

Prior studies have shown that pancreatic α-cells can transdifferentiate into β-cells, and that β-cells de-differentiate and are prone to acquire an α-cell phenotype in type 2 diabetes (T2D). However, the specific human α-cell and β-cell subtypes that are involved in α-to-β-cell and β-to-α-cell transitions are unknown. Here, we have integrated single cell RNA sequencing (scRNA-seq) and single nucleus RNA-seq (snRNA-seq) of isolated human islets and human islet grafts and provide additional insight into α-β cell fate switching. Using this approach, we make seven novel observations. 1) There are five different GCG -expressing human α-cell subclusters [α1, α2, α-β-transition 1 (AB-Tr1), α-β-transition 2 (AB-Tr2), and α-β (AB) cluster] with different transcriptome profiles in human islets from non-diabetic donors. 2) The AB subcluster displays multihormonal gene expression, inferred mostly from snRNA-seq data suggesting identification by pre-mRNA expression. 3) The α1, α2, AB-Tr1, and AB-Tr2 subclusters are enriched in genes specific for α-cell function while AB cells are enriched in genes related to pancreatic progenitor and β-cell pathways; 4) Trajectory inference analysis of extracted α- and β-cell clusters and RNA velocity/PAGA analysis suggests a bifurcate transition potential for AB towards both α- and β-cells. 5) Gene commonality analysis identifies ZNF385D, TRPM3, CASR, MEG3 and HDAC9 as signature for trajectories moving towards β-cells and SMOC1, PLCE1, PAPPA2, ZNF331, ALDH1A1, SLC30A8, BTG2, TM4SF4, NR4A1 and PSCK2 as signature for trajectories moving towards α-cells. 6) Remarkably, in contrast to the events in vitro , the AB subcluster is not identified in vivo in human islet grafts and trajectory inference analysis suggests only unidirectional transition from α-to-β-cells in vivo . 7) Analysis of scRNA-seq datasets from adult human T2D donor islets reveals a clear unidirectional transition from β-to-α-cells compatible with dedifferentiation or conversion into α-cells. Collectively, these studies show that snRNA-seq and scRNA-seq can be leveraged to identify transitions in the transcriptional status among human islet endocrine cell subpopulations in vitro , in vivo , in non-diabetes and in T2D. They reveal the potential gene signatures for common trajectories involved in interconversion between α- and β-cells and highlight the utility and power of studying single nuclear transcriptomes of human islets in vivo . Most importantly, they illustrate the importance of studying human islets in their natural in vivo setting.

Protection of β-pancreatic cells from dysfunctionality of insulin using vitexin by apoptosis of INS-1 cells

AIMS

This study was performed to explore the possible beneficial effects of vitexin on high glucose (HG)-induced cytotoxicity in pancreatic β-cells.

METHODS

INS-1 pancreatic β-cell line has used this study. HG-induced (33 Mm) exposed INS-1 cell death; the apoptosis INS-1 cells treated vitexin 10, 20, 40, and 80 µg/mL for 24 hours. The anti-apoptosis properties were evaluated by MTT assay, glucose-stimulated insulin secretion assay, biochemical assay, annexin-V-FITC staining and western blot analysis.

RESULTS

These findings demonstrate that vitexin treatment improved the HG-exposure, reduced the INS-1 cell viability and significantly enhanced glucose-stimulated insulin secretion in a dose-dependent manner. The antioxidant studies revealed that vitexin treatment significantly decreased lipid peroxidation and reactive oxygen species and increased antioxidant level of INS-1 cell line in 24 hrs. The findings of the study suggested that in the vitexin treatment group, pancreatic apoptosis and Bax protein expression reduced significantly. At the same time, Bcl-2 protein expression increased, and NF-κB protein in HG-induced INS-cells was inhibited.

CONCLUSION

Therefore, our results suggest that vitexin can be successfully used to regulate the expression of Bcl-2 family proteins, reduce lipid peroxidation and to improve the secretion of antioxidants in pancreatic β-cell lines.

The therapeutic mechanism of Yuye decoction on type 2 diabetes mellitus based on network pharmacology and experimental verification

ETHNOPHARMACOLOGICAL RELEVANCE

Yuye decoction (YYD) has been widely used as a folk Chinese herbal formula in clinical treatment of type 2 diabetes mellitus(T2DM) for many years. However, its mechanism is still unclear.

AIM OF THE STUDY

The aim of this study was to explore the potential mechanism of YYD against T2DM initially by UHPLC-MS/MS combining with network pharmacology, molecular docking techniques and experimental validation.

MATERIALS AND METHODS

The main ingredients in the water extract of YYD were initially identified using UHPLC-MS/MS analysis. Combined with network pharmacology and molecular docking techniques, the YYD key compounds-core targets-key signaling pathways network was constructed and the binding activity of key components to core targets was validated. The T2DM rat model was induced by Streptozotocin combined with high glucose and high fat diets. The apoptosis cell model of mouse islet β-cell of Min6 was induced by high-glucose and palmitic acid. Histopathological and immunofluorescence satining were used to evaluate pancreatic islet β-cell function and apoptosis in rats. Min6 cell viability and apoptosis ratio were evaluated by CCK-8 and TUNEL staining. The predicted targets and pathways were validated by experiments in vitro and in vivo.

RESULTS

The 56 compounds from YYD were identified by UHPLC-MS/MS. The potential targets of the above compounds were predicted by online compound target database, among of which 362 targets were associated with T2DM. Protein-protein interaction analysis identified the main targets such as SRC, MAPK1, PIK3R1, AKT1, HRAS and HSP90AA1, which were considered as the therapeutic targets of YYD on against T2DM. Functional enrichment analysis revealed that PI3K/AKT, FoxO and apoptosis signaling pathways were significantly enriched. Molecular docking results showed that compounds of monolinolein, neomangiferin, mangiferin, pelargonidin-3-O-glucoside and acacetin from YYD had high binding activities to PIK3R1, AKT1, Sirt1 and FoxO1. Therefore, PI3K/AKT1, Sirt1/FoxO1 and apoptotic signaling pathways were considered as predicted targets for experimental validation study. Animal experiments showed that YYD reduced blood glucose levels, improved pancreatic dysfunction and pancreatic islet β-cells apoptosis in T2DM rats which contributed to the activation of AKT1 and FoxO1 and their related signaling molecules. These results were confirmed in Min6 cell model induced by high-glucose and palmitic acid.

CONCLUSIONS

In summary, this study systematically visualized the possible therapeutic effects and mechanisms of YYD on T2DM through the network pharmacology approach and experimental study. The results indicated that YYD could prevent pancreatic islet dysfunction and reverse islet of β-cells apoptosis possibly via PI3K/AKT1, Sirt1/FoxO1 signaling pathways.

The involvement of EGR1 in neuron apoptosis in the in vitro model of spinal cord injury via BTG2 up-regulation

OBJECTIVE

EGR1 has been implicated in the progression of spinal cord injury (SCI). Nevertheless, its specific mechanism in SCI remains to be investigated. Hence, this study explored the potential mechanism of EGR1 in SCI by focusing on neuron apoptosis.

METHODS

H₂O₂ was utilized to treat rat neurons-dorsal spinal cord (RN-dsc) for the construction of an in vitro model of SCI. Afterwards, cell survival, apoptosis, and LDH leakage were detected to evaluate the injury degree of H₂O₂-treated RN-dsc. The expression of apoptosis-related proteins was also measured. Additionally, EGR1 was silenced and/or BTG2 was overexpressed in RN-dsc before H₂O₂ treatment to assess the impacts of EGR1 and BTG2 on H₂O₂-induced RN-dsc. Jasper online website was utilized to predict binding sites of EGR1 on BTG2, and dual-luciferase reporter gene and chromatin immunoprecipitation (ChIP) assays were utilized to verify the binding between EGR1 and BTG2.

RESULTS

H₂O₂ treatment suppressed survival and promoted apoptosis in RN-dsc, accompanied by upregulated LDH, Bax, and cleaved-caspase-3 and down-regulated Bcl-2. Moreover, EGR1 and BTG2 were up-regulated in H₂O₂-induced RN-dsc. Mechanistically, EGR1 was bound to the promoter of BTG2 to transcriptionally activate BTG2. EGR1 knockdown diminished apoptosis and LDH, Bax, and cleaved-caspase-3 levels while elevating survival and Bcl-2 levels in H₂O₂-induced RN-dsc. These effects of EGR1 knockdown were abrogated by further BTG2 overexpression.

DISCUSSION

Conclusively, EGR1 promotes H₂O₂-induced apoptosis in RN-dsc by activating BTG2 transcription.

G protein-coupled estrogen receptor activation by bisphenol-A disrupts the protection from apoptosis conferred by the estrogen receptors ERα and ERβ in pancreatic beta cells

17β-estradiol protects pancreatic β-cells from apoptosis via the estrogen receptors ERα, ERβ and GPER. Conversely, the endocrine disruptor bisphenol-A (BPA), which exerts multiple effects in this cell type via the same estrogen receptors, increased basal apoptosis. The molecular-initiated events that trigger these opposite actions have yet to be identified. We demonstrated that combined genetic downregulation and pharmacological blockade of each estrogen receptor increased apoptosis to a different extent. The increase in apoptosis induced by BPA was diminished by the pharmacological blockade or the genetic silencing of GPER, and it was partially reproduced by the GPER agonist G1. BPA and G1-induced apoptosis were abolished upon pharmacological inhibition, silencing of ERα and ERβ, or in dispersed islet cells from ERβ knockout (BERKO) mice. However, the ERα and ERβ agonists PPT and DPN, respectively, had no effect on beta cell viability. To exert their biological actions, ERα and ERβ form homodimers and heterodimers. Molecular dynamics simulations together with proximity ligand assays and coimmunoprecipitation experiments indicated that the interaction of BPA with ERα and ERβ as well as GPER activation by G1 decreased ERαβ heterodimers. We propose that ERαβ heterodimers play an antiapoptotic role in beta cells and that BPA- and G1-induced decreases in ERαβ heterodimers lead to beta cell apoptosis. Unveiling how different estrogenic chemicals affect the crosstalk among estrogen receptors should help to identify diabetogenic endocrine disruptors.

Effects of hypothyroidism on the female pancreas involve the regulation of estrogen receptors

This study aimed to investigate the impact of short-time hypothyroidism on the expression of aromatase, estrogen receptors (ERα, β), and GPR30 in the pancreas of female rabbits. The formation of new islets and the expression of insulin, GLUT4, and lactate dehydrogenase (LDH) were also analyzed. This purpose is based on actions that thyroid hormones and estrogens have on β-cells differentiation, acinar cell function, and insulin secretion. Twelve Chinchilla-breed adult virgin female rabbits were divided into control (n = 6) and hypothyroid (n = 6; methimazole 10 mg/kg for 30 days) groups. In the complete pancreas, expressions of aromatase and estrogen receptors, as well as proinsulin, GLUT4, and LDH were determined by western blot. Characteristics of islets were measured in slices of the pancreas with immunohistochemistry for insulin. Islet and acinar cells express aromatase, ERα, ERβ, and GPR30. Hypothyroidism increased the expression of ERα and diminished that for aromatase, ERβ, and GPR30 in the pancreas. It also promoted a high number of extra small islets (new islets) and increased the expression of proinsulin and GLUT4 in the pancreas. Our results show that actions of thyroid hormones and estrogens on β-cells neogenesis, acinar cell function, and synthesis and secretion of insulin are linked. Thus, the effects of hypothyroidism on the pancreas could include summatory actions of thyroid hormones plus estrogens. Our findings indicate the importance of monitoring estrogen levels and actions on the pancreas of hypothyroid women, particularly when serum estrogen concentrations are affected such as menopausal, pregnant, and those with contraceptive use.

Integrating Additive Manufacturing Techniques to Improve Cell-Based Implants for the Treatment of Type 1 Diabetes

The increasing global prevalence of endocrine diseases like type 1 diabetes mellitus (T1DM) elevates the need for cellular replacement approaches, which can potentially enhance therapeutic durability and outcomes. Central to any cell therapy is the design of delivery systems that support cell survival and integration. In T1DM, well-established fabrication methods have created a wide range of implants, ranging from 3D macro-scale scaffolds to nano-scale coatings. These traditional methods, however, are often challenged by their inherent limitations in reproducible and discrete fabrication, particularly when scaling to the clinic. Additive manufacturing (AM) techniques provide a means to address these challenges by delivering improved control over construct geometry and microscale component placement. While still early in development in the context of T1DM cellular transplantation, the integration of AM approaches serves to improve nutrient material transport, vascularization efficiency, and the accuracy of cell, matrix, and local therapeutic placement. This review highlights current methods in T1DM cellular transplantation and the potential of AM approaches to overcome these limitations. In addition, emerging AM technologies and their broader application to cell-based therapy are discussed.

The Role of Estrogen Signaling in Cellular Iron Metabolism in Pancreatic β Cells

ABSTRACT

Several lines of evidence suggest that estrogen (17-β estradiol; E2) protects against diabetes mellitus and plays important roles in pancreatic β-cell survival and function. Mounting clinical and experimental evidence also suggest that E2 modulates cellular iron metabolism by regulating the expression of several iron regulatory genes, including hepcidin (HAMP), hypoxia-inducible factor 1-α, ferroportin (SLC40A1), and lipocalin (LCN2). However, whether E2 regulates cellular iron metabolism in pancreatic β cells and whether the antidiabetic effects of E2 can be, at least partially, attributed to its role in iron metabolism is not known. In this context, pancreatic β cells express considerable levels of conventional E2 receptors (ERs; mainly ER-α) and nonconventional G protein-coupled estrogen receptors and hence responsive to E2 signals. Moreover, pancreatic islet cells require significant amounts of iron for proper functioning, replication and survival and, hence, well equipped to manage cellular iron metabolism (acquisition, utilization, storage, and release). In this review, we examine the link between E2 and cellular iron metabolism in pancreatic β cells and discuss the bearing of such a link on β-cell survival and function.

RETRACTED: MicroRNA-16-5p/BTG2 axis affects neurological function, autophagy and apoptosis of hippocampal neurons in Alzheimer's disease

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief as there are concerns about the reliability of the results. Concerns have been raised about the western blot bands in Figures 6 B + D having the same eyebrow shaped phenotype as found in many other publications as detailed here (https://pubpeer.com/publications/B32F93859FBAA13471ED0FFCA5BCB6). The journal requested the corresponding author to comment on these concerns and send the raw data, however the author was not able to provide uncropped images of the original gels. The Editor-in-Chief therefore no longer has confidence in the data and conclusions of this study.

Astaxanthin-s-allyl cysteine diester against high glucose-induced neuronal toxicity in vitro and diabetes-associated cognitive decline in vivo: Effect on p53, oxidative stress and mitochondrial function

Neuroprotective effect of astaxanthin-s-allyl cysteine diester (AST-SAC) against high glucose (HG)-induced oxidative stress in in vitro and cognitive decline under diabetes conditions in in vivo has been explored. Pretreatment of AST-SAC (5, 10 and 15 μM) dose-dependently preserved the neuronal cells (SH-SY5Y) viability against HG toxicity through i) decreasing oxidative stress (decreasing reactive oxygen species generation and increasing endogenous antioxidants level); ii) protecting mitochondrial function [oxidative phosphorylation (OXPHOS) complexes activity and mitochondrial membrane potential (MMP)]; and iii) decreasing p53 level thereby subsequently decreasing the level of apoptotic marker proteins. Male Spraque-Dawley rats were orally administered AST-SAC (1 mg/kg/day) for 45 days in streptozotocin-induced diabetes mellitus (DM) rats. AST-SAC administration prevented the loss of spatial memory in DM rats as determined using the novel object location test. AST-SAC administration alleviated the DM-induced injury in brain such as increased cholinesterases activity, elevated oxidative stress and mitochondrial dysfunction. Altogether, the results from the present study demonstrated that AST-SAC averted the neuronal apoptosis and preserved the cognitive function against HG toxicity under DM conditions.

Lin28a ameliorates glucotoxicity-induced β-cell dysfunction and apoptosis

An excessive and prolonged increase in glucose levels causes β-cell dysregulation, which is accompanied by impaired insulin synthesis and secretion, a condition known as glucotoxicity. Although it is known that both Lin28a and Lin28b regulate glucose metabolism, other molecular mechanisms that may protect against glucotoxicity are poorly understood. We investigated whether Lin28a overexpression can improve glucotoxicity-induced β-cell dysregulation in INS-1 and primary rat islet cells. INS-1, a rat insulinoma cell line was cultured and primary rat islet cells were isolated from SD-rats. To define the effect of Lin28a in chronic high glucose-induced β-cell dysregulation, we performed several in vitro and ex-vivo experiments. Chronic exposure to high glucose led to a downregulation of Lin28a mRNA and protein expression, followed by a decrease in insulin mRNA expression and secretion in β-cells. The mRNA and protein expression levels of PDX-1 and BETA2, were reduced; The levels of apoptotic factors, including c-caspase3 and the Bax/Bcl-2 ratio, were increased due to glucotoxicity. Adenovirus-mediated Lin28a overexpression in β-cells reversed the glucotoxicity-induced reduction of insulin secretion and insulin mRNA expression via regulation of β-cell-enriched transcription factors such as PDX-1 and BETA2. Adenovirus-mediated overexpression of Lin28a downregulated the glucotoxicity-induced upregulation of c-caspase3 levels and the Bax/Bcl-2 ratio, while inhibition of endogenous Lin28a by small interfering RNA resulted in their up-regulation. Lin28a counteracted glucotoxicity-induced downregulation of p-Akt and p-mTOR. Our results suggest that Lin28a protects pancreatic β-cells from glucotoxicity through inhibition of apoptotic factors via the PI3 kinase/Akt/mTOR pathway.

Elevation of miR-146a Inhibits BTG2/BAX Expression to Ameliorate Postoperative Cognitive Dysfunction Following Probiotics (VSL#3) Treatment

It has been reported that the gut microbiome modulates postoperative cognitive dysfunction (POCD), and that administration of probiotics (VSL#3) may effectively relieve POCD. In this study, we aimed to identify the underlying mechanism of VSL#3 in POCD. A mouse model of POCD was constructed in adult male C57BL/6 mice, which were then treated with VSL#3. VSL#3 exerted a protective role against POCD and resultant neuronal apoptosis. The expression of miR-146a was found to be downregulated in hippocampal tissues of POCD mice, while VSL#3 could restore its expression. Loss- and gain-function approaches were conducted to determine the roles of microRNA (miR)-146a, B-cell translocation gene 2 (BTG2), and Bcl-2-associated X protein (Bax) in post-operative effects on cognitive function and neuronal apoptosis. The levels of reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD) were measured to determine oxidative stress in brain tissue. The dual-luciferase reporter gene assay identified that miR-146a could target BTG2 and negatively regulate its expression. BTG2 knockdown suppressed neuronal apoptosis and contributed to shortened time of latency, prolonged time of mice spent in the target quadrant, and reduced oxidative stress through downregulating Bax expression. Finally, VSL#3 treatment upregulated the expression of miR-146a to block BTG2/Bax axis and consequently inhibited neuronal apoptosis and reduced oxidative stress in POCD mice. Taken together, the study suggested that miR-146a-mediated suppression of BTG2/Bax contributed to the protective role of probiotics treatment against POCD.

Cross-sectional and prospective relationships of endogenous progestogens and estrogens with glucose metabolism in men and women: a KORA F4/FF4 Study

INTRODUCTION

Relationships between endogenous female sex hormones and glycemic traits remain understudied, especially in men. We examined whether endogenous 17α-hydroxyprogesterone (17-OHP), progesterone, estradiol (E2), and free estradiol (fE2) were associated with glycemic traits and glycemic deterioration.

RESEARCH DESIGN AND METHODS

921 mainly middle-aged and elderly men and 390 perimenopausal/postmenopausal women from the German population-based Cooperative Health Research in the Region of Augsburg (KORA) F4/FF4 cohort study were followed up for a median of 6.4 years. Sex hormones were measured at baseline using mass spectrometry. We calculated regression coefficients (β) and ORs with 95% CIs using multivariable-adjusted linear and logistic regression models for Z-standardized hormones and glycemic traits or glycemic deterioration (ie, worsening of categorized glucose tolerance status), respectively.

RESULTS

In the cross-sectional analysis (n=1222 men and n=594 women), in men, 17-OHP was inversely associated with 2h-glucose (2hG) (β=-0.067, 95% CI -0.120 to -0.013) and fasting insulin (β=-0.074, 95% CI -0.118 to -0.030), and positively associated with Quantitative Insulin Sensitivity Check Index (QUICKI) (β=0.061, 95% CI 0.018 to 0.105). Progesterone was inversely associated with fasting insulin (β=-0.047, 95% CI -0.088 to -0.006) and positively associated with QUICKI (β=0.041, 95% CI 0.001 to 0.082). E2 was inversely associated with fasting insulin (β=-0.068, 95% CI -0.116 to -0.020) and positively associated with QUICKI (β=0.059, 95% CI 0.012 to 0.107). fE2 was positively associated with glycated hemoglobin (HbA_1c) (β=0.079, 95% CI 0.027 to 0.132). In women, 17-OHP was positively associated with fasting glucose (FG) (β=0.068, 95% CI 0.014 to 0.123). fE2 was positively associated with FG (β=0.080, 95% CI 0.020 to 0.141) and HbA_1c (β=0.121, 95% CI 0.062 to 0.180). In the sensitivity analyses restricted to postmenopausal women, we observed a positive association between 17-OHP and glycemic deterioration (OR=1.518, 95% CI 1.033 to 2.264).

CONCLUSIONS

Inter-relations exist between female sex hormones and glucose-related traits among perimenopausal/postmenopausal women and insulin-related traits among men. Endogenous progestogens and estrogens appear to be involved in glucose homeostasis not only in women but in men as well. Further well-powered studies assessing causal associations between endogenous female sex hormones and glycemic traits are warranted.

Plasma exosome-derived B-cell translation gene 1: a predictive marker for the prognosis in patients with non-small cell lung cancer

Objective: In this study, we wanted to investigate the plasma exosome-derived B-cell translocation gene 1 (BTG-1) level as a predictive marker for the prognosis in patients with Non-small cell lung cancer (NSCLC).

Patients and Methods: The expression of BTG-1 protein and BTG-1 mRNA in NSCLC tissues and adjacent tissues of 98 enrolled patients were detected by immunohistochemistry (IHC), and RT-PCR. Exosome-rich fractions were isolated from the plasma of 262 NSCLC patients. ELISA was used to detect plasma exosome-derived BTG-1 levels to evaluate the predictive value for the prognosis in patients with NSCLC.

Results: IHC staining showed that the positive expression rate of BTG-1 protein in NSCLC tissues was 58.16%, whereas that in adjacent tissues was 91.84%. RT-PCR showed that BTG-1 mRNA expression was significantly lower in NSCLC tissues than in adjacent tissues (52.04% vs 87.76%, P < 0.05). Moreover, low plasma exosome-derived BTG-1 levels were related to tumor diameter, stage, metastasis, the degree of tumor differentiation, and abnormal carcinoembryonic antigen (CEA) levels. Multivariate Cox regression analysis showed that both the disease-free survival (DFS) and overall survival (OS) were shorter in patients with low plasma exosome-derived BTG-1 level compared with patients with high plasma exosome-derived BTG-1 level.

The AUROC of plasma exosome-derived BTG-1 for 3-year DFS and 3-year OS were 0.94(95% CI; 0.91-0.98) and 0.94(95% CI: 0.90-0.98), respectively. For 3-year DFS, plasma exosome-derived BTG-1 had a sensitivity 91.0% and a specificity 82.3% for 3-year DFS, and a sensitivity 81.7% and a specificity 93.0% for 3-year OS, respectively.

Conclusions: Plasma exosome-derived BTG-1 may be a potential biomarker for the prognosis in patients with NSCLC.

Estrogen-dependent hippocampal wiring as a risk factor for age-related dementia in women

Women are more prone than men to develop age-related dementia, such as Alzheimer's disease (AD). This has been linked to the marked decrease in circulating estrogens during menopause. This review proposes to change this perspective and consider women's vulnerability to developing AD as a consequence of sex differences in the neurobiology of memory, focusing on the hippocampus. The hippocampus of cognitively impaired subjects tends to shrink with age; however, in many cases, this can be prevented by exercise or cognitive training, suggesting that if you do not use the hippocampus you lose it. We will review the developmental trajectory of sex steroids-regulated differences on the hippocampus, proposing that the overall shaping action of sex-steroids results in a lower usage of the hippocampus in females, which in turn makes them more vulnerable to the effects of ageing, the "network fragility hypothesis". To explain why women rely less on hippocampus-dependent strategies, we propose a "computational hypothesis" that is based on experimental evidence suggesting that the direct effects of estrogens on hippocampal synaptic and structural plasticity during the estrous-cycle confers instability to the memory-dependent hippocampal network. Finally, we propose to counteract AD with training and/or treatments, such as orienteering, which specifically favour the use of the hippocampus.

Tropisetron attenuates pancreas apoptosis in the STZ-induced diabetic rats: involvement of SIRT1/NF-κB signaling

BACKGROUND

Diabetes mellitus (DM) is one of the most common diseases in the worldwide. Type 1 diabetes mellitus (T1DM) is characterized by insulin deficiency and beta cells apoptosis. Tropisetron as a 5-HT3 receptor antagonist has positive effects on the inflammation, apoptosis and glucose lowering. The aim of this study was to investigate the effect of tropisetron on β-cells apoptosis and its possible pathways.

METHODS

Animals were divided into five equal groups: the control, tropisetron, diabetes, tropisetron-DM and glibenclamide-DM (seven in each group). Tropisetron and glibenclamide were administrated for 2 weeks after type 1 diabetes induction. Real-time PCR, western blot analysis and TUNEL assay were performed.

RESULTS

We found that tropisetron decreased blood glucose and increased insulin secretion. Protein expression of NF-κB was downregulated, while protein expression of SIRT1 upregulated after tropisetron treatment. Moreover, Bax/Bcl2 ratio decreased in tropisetron-DM group and finally, apoptosis improved in pancreas tissue.

CONCLUSIONS

It seems that tropisetron administration improves STZ-induced apoptosis and diabetes in the animals. This effect might be resulted from involvement in NF-κB/ SIRT1 pathway.

Oral DhHP-6 for the Treatment of Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is associated with pancreatic β-cell dysfunction which can be induced by oxidative stress. Deuterohemin-βAla-His-Thr-Val-Glu-Lys (DhHP-6) is a microperoxidase mimetic that can scavenge reactive oxygen species (ROS) in vivo. In our previous studies, we demonstrated an increased stability of linear peptides upon their covalent attachment to porphyrins. In this study, we assessed the utility of DhHP-6 as an oral anti-diabetic drug in vitro and in vivo. DhHP-6 showed high resistance to proteolytic degradation in vitro and in vivo. The degraded DhHP-6 product in gastrointestinal (GI) fluid retained the enzymatic activity of DhHP-6, but displayed a higher permeability coefficient. DhHP-6 protected against the cell damage induced by H₂O₂ and promoted insulin secretion in INS-1 cells. In the T2DM model, DhHP-6 reduced blood glucose levels and facilitated the recovery of blood lipid disorders. DhHP-6 also mitigated both insulin resistance and glucose tolerance. Most importantly, DhHP-6 promoted the recovery of damaged pancreas islets. These findings suggest that DhHP-6 in physiological environments has high stability against enzymatic degradation and maintains enzymatic activity. As DhHP-6 lowered the fasting blood glucose levels of T2DM mice, it thus represents a promising candidate for oral administration and clinical therapy.