Glutamine Promotes Porcine Intestinal Epithelial Cell Proliferation through the Wnt/β-Catenin Pathway

Glutamine (Gln) is a critical nutrient required by neonatal mammals for intestinal growth, especially for newborn piglets. However, the mechanisms underlying the role of Gln in porcine intestinal epithelium development are not fully understood. The objective of the current study was to explore the possible signaling pathway involved in the promotion of porcine intestinal epithelial cell (IPEC-J2) proliferation by Gln. The results showed that 1 mM Gln promoted IPEC-J2 cell proliferation, and tandem mass tag proteomics revealed 973 differentially expressed proteins in Gln-treated IPEC-J2 cells, 824 of which were upregulated and 149 of which were downregulated. Moreover, gene set enrichment analysis indicated that the Wnt signaling pathway is activated by Gln treatment. Western blotting analysis further confirmed that Gln activated the Wnt/β-catenin signaling pathway. In addition, Gln increased not only cytosolic β-catenin but also nuclear β-catenin protein expression. LF3 (a β-catenin/TCF4 interaction inhibitor) assay and β-catenin knockdown demonstrated that Gln-mediated promotion of Wnt/β-catenin signaling and cell proliferation were blocked. Furthermore, the inhibition of TCF4 expression suppressed Gln-induced cell proliferation. These findings further confirmed that Wnt/β-catenin signaling is involved in the promotion of IPEC-J2 cell proliferation by Gln. Collectively, these findings demonstrated that Gln positively regulated IPEC-J2 cell proliferation through the Wnt/β-catenin pathway. These data greatly enhance the current understanding of the mechanism by which Gln regulates intestinal development.

Phospholipase D Mediates Glutamine-Induced mTORC1 Activation to Promote Porcine Intestinal Epithelial Cell Proliferation

BACKGROUND

The intestinal epithelium is one of the fastest self-renewal tissues in the body, and glutamine plays a crucial role in providing carbon and nitrogen for biosynthesis. In intestinal homeostasis, phosphorylation-mediated signaling networks that cause altered cell proliferation, differentiation, and metabolic regulation have been observed. However, our understanding of how glutamine affects protein phosphorylation in the intestinal epithelium is limited, and identifying the essential signaling pathways involved in regulating intestinal epithelial cell growth is particularly challenging.

OBJECTIVES

This study aimed to identify the essential proteins and signaling pathways involved in glutamine's promotion of porcine intestinal epithelial cell proliferation.

METHODS

Phosphoproteomics was applied to describe the protein phosphorylation landscape under glutamine treatment. Kinase-substrate enrichment analysis was subjected to predict kinase activity and validated by qRT-PCR and Western blotting. Cell Counting Kit-8, glutamine rescue experiment, chloroquine treatment, and 5-fluoro-2-indolyl deschlorohalopemide inhibition assay revealed the possible underlying mechanism of glutamine promoting porcine intestinal epithelial cell proliferation.

RESULTS

In this study, glutamine starvation was found to significantly suppress the proliferation of intestinal epithelial cells and change phosphoproteomic profiles with 575 downregulated sites and 321 upregulated sites. Interestingly, phosphorylation of eukaryotic initiation factor 4E-binding protein 1 at position Threonine70 was decreased, which is a crucial downstream of the mechanistic target of rapamycin complex 1 (mTORC1) pathway. Further studies showed that glutamine supplementation rescued cell proliferation and mTORC1 activity, dependent on lysosomal function and phospholipase D activation.

CONCLUSION

In conclusion, glutamine activates mTORC1 signaling dependent on phospholipase D and a functional lysosome to promote intestinal epithelial cell proliferation. This discovery provides new insight into regulating the homeostasis of the intestinal epithelium, particularly in pig production.

The Alleviating Effect of Taxifolin on Deoxynivalenol-Induced Damage in Porcine Intestinal Epithelial Cells

Deoxynivalenol (DON) contamination in feed is a global concern that severely threatens the health of animals and humans. Taxifolin (TA) is a natural flavonoid, a member of the polyphenols, that possesses robust antioxidant properties. This study aimed to investigate the effect of TA on DON-induced damage in porcine intestinal epithelial cells (IPEC-J2). The cells were pre-incubated with a series of concentrations of TA for 24 h and exposed to DON (0.5 μg/mL) for another 24 h. The results showed that pretreatment with TA (150 μM) significantly inhibited the DON-induced decline in cell viability (p < 0.05) and cell proliferation (p < 0.01). Additionally, 150 μM TA also alleviated DON-induced apoptosis (p < 0.01). Moreover, TA decreased the production of reactive oxygen species (ROS) induced by DON (p < 0.01). In addition, TA attenuated DON-induced cell junction damage (p < 0.05). Further experiments showed that TA reversed the DON-induced reduction in antioxidant capacity in the IPEC-J2 cells, probably via activating the Nrf2 signaling pathway (p < 0.05). Collectively, these findings suggest that 150 μM TA can protect against 0.5 μg/mL DON-induced damage to IPEC-J2 cells, potentially via the activation of the Nrf2 signaling pathway. This study provides insight into TA's potential to act as a green feed additive in the pig farming industry and its efficacy in counteracting DON-induced intestinal damage.

Piceatannol Alleviates Deoxynivalenol-Induced Damage in Intestinal Epithelial Cells via Inhibition of the NF-κB Pathway

Deoxynivalenol (DON) is a common mycotoxin that is widely found in various foods and feeds, posing a potential threat to human and animal health. This study aimed to investigate the protective effect of the natural polyphenol piceatannol (PIC) against DON-induced damage in porcine intestinal epithelial cells (IPEC-J2 cells) and the underlying mechanism. The results showed that PIC promotes IPEC-J2 cell proliferation in a dose-dependent manner. Moreover, it not only significantly relieved DON-induced decreases in cell viability and proliferation but also reduced intracellular reactive oxygen species (ROS) production. Further studies demonstrated that PIC alleviated DON-induced oxidative stress damage by increasing the protein expression levels of the antioxidant factors NAD(P)H quinone oxidoreductase-1 (NQO1) and glutamate-cysteine ligase modifier subunit (GCLM), and the mRNA expression of catalase (CAT), Superoxide Dismutase 1 (SOD1), peroxiredoxin 3 (PRX3), and glutathione S-transferase alpha 4 (GSTα4). In addition, PIC inhibited the activation of the nuclear factor-B (NF-κB) pathway, downregulated the mRNA expression of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α) to attenuate DON-induced inflammatory responses, and further mitigated DON-induced cellular intestinal barrier injury by regulating the protein expression of Occludin. These findings indicated that PIC had a significant protective effect against DON-induced damage. This study provides more understanding to support PIC as a feed additive for pig production.

Extracellular Glutamine Promotes Intestinal Porcine Epithelial Cell Proliferation via Arf1-mTORC1 Pathway Independently of Rag GTPases

Glutamine (Gln) is the major energy source of intestinal porcine epithelial cells (IPEC-J2 cells) and plays a critical role in the nutritional physiological function of the intestine. However, the underlying mechanism requires further investigation. Here, the Gln-sensing pathway in IPEC-J2 cells was investigated. The results showed that Gln increased the cell proliferation. Subsequently, an analysis of the phosphorylated proteome revealed that Gln markedly upregulated ribosomal protein S6 (RPS6) phosphorylation at serine 235/236, suggesting that Gln activated the mTORC1 pathway. mTOR inhibition revealed that Gln promotes cell proliferation through the mTORC1 pathway. Similarly, blocking ADP-ribosylation factor 1 (Arf1) activity indicated that Gln-induced mTORC1 activation promoted cell proliferation in an Arf1-dependent manner. Additionally, the RagA/B pathway did not participate in Gln-induced mTORC1 activation. Collectively, these findings suggest that Gln-induced mTORC1 activation promotes IPEC-J2 cell proliferation via Arf1, not Rag GTPases. These results broaden our understanding of functional-cell-sensing amino acids, particularly Gln, that are regulated by mTORC1.

Glutamine Regulates Gene Expression Profiles to Increase the Proliferation of Porcine Intestinal Epithelial Cells and the Expansion of Intestinal Stem Cells

The intestinal epithelium is known for its rapid self-renewal, and glutamine is crucial in providing carbon and nitrogen for biosynthesis. However, understanding how glutamine affects gene expression in the intestinal epithelium is limited, and identifying the essential genes and signals involved in regulating intestinal epithelial cell growth is particularly challenging. In this study, glutamine supplementation exhibited a robust acceleration of intestinal epithelial cell proliferation and stem cell expansion. RNA sequencing indicated diverse transcriptome changes between the control and glutamine supplementation groups, identifying 925 up-regulated and 1152 down-regulated genes. The up-regulated DEGs were enriched in the KEGG pathway of cell cycle and GO terms of DNA replication initiation, regulation of phosphatidylinositol 3-kinase activity, DNA replication, minichromosome maintenance protein (MCM) complex, and ATP binding, whereas the down-regulated DEGs were enriched in the KEGG pathway of p53 signaling pathway, TNF signaling pathway, and JAK-STAT signaling pathway and GO terms of inflammatory response and intrinsic apoptotic signaling pathway in response to endoplasmic reticulum stress. Furthermore, GSEA analysis revealed a significant up-regulation of the cell cycle, DNA replication initiation, ATP-dependent RNA helicase activity, and down-regulation of the TNF signaling pathway. The protein-protein association network of the intersecting genes highlighted the significance of DNA replication licensing factors (MCM3, MCM6, and MCM10) in promoting intestinal epithelial growth in response to glutamine. Based on these findings, we propose that glutamine may upregulate DNA replication licensing factors, leading to increased PI3K/Akt signaling and the suppression of TNF, JAK-STAT, and p53 pathways. Consequently, this mechanism results in the proliferation of porcine intestinal epithelial cells and the expansion of intestinal stem cells.

Mediating effects of self-esteem on the relationship between mindful parenting and social anxiety level in Chinese adolescents

This study aimed to investigate the relationship between mindful parenting and social anxiety level in Chinese adolescents and to explore the mediating roles of self-esteem between mindful parenting and social anxiety level. A total of 302 adolescents and their main caregivers were investigated by using the Chinese version of the Mindful Parenting Scale, Self-Esteem Scale and the Center for Epidemiological Studies Depression Scale and the Social Anxiety Scale. Related analysis was used to investigate the relationship between mindful parenting, self-esteem and social anxiety level. Mindful parenting and self-esteem were significantly associated with social anxiety level. Self-esteem mediated the relationship between mindful parenting and social anxiety level. Both mindful discipline and being in the moment influenced adolescents' social anxiety level through self-esteem. Self-esteem completely mediated the association between mindful parenting and social anxiety level. Longitudinal research is needed to better understand the relationship between mindful parenting and social anxiety level in adolescents.

Predictors of rapid eye movement sleep behavior disorder in patients with Parkinson’s disease based on random forest and decision tree

Background and objectives

Sleep disorders related to Parkinson’s disease (PD) have recently attracted increasing attention, but there are few clinical reports on the correlation of Parkinson’s disease patients with rapid eye movement (REM) sleep behavior disorder (RBD). Therefore, this study conducted a cognitive function examination for Parkinson’s disease patients and discussed the application effect of three algorithms in the screening of influencing factors and risk prediction effects.

Methods

Three algorithms (logistic regression, machine learning-based regression trees and random forest) were used to establish a prediction model for PD-RBD patients, and the application effects of the three algorithms in the screening of influencing factors and the risk prediction of PD-RBD were discussed.

Results

The subjects included 169 patients with Parkinson’s disease (Parkinson’s disease with RBD [PD-RBD] = 69 subjects; Parkinson’s disease without RBD [PD-nRBD] = 100 subjects). This study compared the predictive performance of RF, decision tree and logistic regression, selected a final model with the best model performance and proposed the importance of variables in the final model. After the analysis, the accuracy of RF (83.05%) was better than that of the other models (decision tree = 75.10%, logistic regression = 71.62%). PQSI, Scopa-AUT score, MoCA score, MMSE score, AGE, LEDD, PD-course, UPDRS total score, ESS score, NMSQ, disease type, RLSRS, HAMD, UPDRS III and PDOnsetage are the main variables for predicting RBD, along with increased weight. Among them, PQSI is the most important factor. The prediction model of Parkinson’s disease RBD that was established in this study will help in screening out predictive factors and in providing a reference for the prognosis and preventive treatment of PD-RBD patients.

Conclusions

The random forest model had good performance in the prediction and evaluation of PD-RBD influencing factors and was superior to decision tree and traditional logistic regression models in many aspects, which can provide a reference for the prognosis and preventive treatment of PD-RBD patients.

Dietary Hermetia illucens Larvae Meal Improves Growth Performance and Intestinal Barrier Function of Weaned Pigs Under the Environment of Enterotoxigenic Escherichia coli K88

The aim of this study was to evaluate the effect of Hermetia illucens larvae meal (HI) on the growth performance and intestinal barrier function of weaned pigs. To achieve this, 72 weaned pigs [28-day-old, 8.44 ± 0.04 kg body weight (BW)] were randomly assigned to three dietary treatments: basal diet (negative control, NC), zinc oxide-supplemented diet (positive control, PC), and HI-supplemented diet [100% replacement of fishmeal (FM), HI], for 28 days in the presence of enterotoxigenic Escherichia coli (ETEC). The results showed that HI and PC increased (p < 0.05) the average daily gain (ADG) and average daily feed intake (ADFI) of weaned pigs from day 1 to 14, and decreased diarrhea incidence from day 1 to 28. Additionally, HI increased (p < 0.05) claudin-1, occludin, mucin-1 (MUC-1), and MUC-2 expression, goblet cell number, and secretory immunoglobulin A (sIgA) concentration in the intestine of weaned pigs. Compared with NC, HI downregulated (p < 0.05) interleukin-1β (IL-1β) and IL-8 expression, and upregulated IL-10, transforming growth factor-β (TGF-β), antimicrobial peptide [porcine β defensin 1 (pBD1), pBD2, protegrin 1-5 (PG1-5)] expression in the jejunum or ileum. Moreover, HI decreased (p < 0.05) toll-like receptor 2 (TLR2), phosphorylated nuclear factor-κB (p-NF-κB), and phosphorylated mitogen-activated protein kinase (p-MAPK) expression, and increased sirtuin 1 (SIRT1) expression in the ileum. Additionally, HI increased histone deacetylase 3 (HDAC3) expression and acetylation of histone 3 lysine 27 (acH3k27) in the ileum. Furthermore, HI positively influenced the intestinal microbiota composition and diversity of weaned pigs and increased (p < 0.05) butyrate and valerate concentrations. Overall, dietary HI improved growth performance and intestinal barrier function, as well as regulated histone acetylation and TLR2-NF-κB/MAPK signaling pathways in weaned pigs.

Dietary fatty acids in gut health: Absorption, metabolism and function

In biological responses, fatty acids (FA) are absorbed and metabolized in the form of substrates for energy production. The molecular structures (number of double bonds and chain length) and composition of dietary FA impact digestion, absorption and metabolism, and the biological roles of FA. Recently, increasing evidence indicates that FA are essentially utilized as an energy source and are signaling molecules that exert physiological activity of gut microbiota and immune responses. In addition, FA could serve as natural ligands for orphan G protein-coupled receptors (GPCR), also called free fatty acid receptors (FFAR), which intertwine metabolic and immune systems via multiple mechanisms. The present review explores the recent findings on FA absorption and its impact on gut health, particularly addressing the mechanism by which dietary FA potentially influences intestinal microbiota and epithelial functions. Also, this work attempts to uncover research ideas for devising future strategies for manipulating the composition of dietary FA to regulate gut health and support a normal immune system for metabolic and immune disorders.

Identification of Enterotype and Its Effects on Intestinal Butyrate Production in Pigs

Simple Summary

Enterotype (ET) is defined based on different gut microbial community composition. It has been considered as a critical factor strongly associated with the porcine feed efficiency and growth characteristic. However, little is known about whether the ET clustering depends on the pig breeds and the effects of the different enterotypes on the butyrate metabolism in pigs. Therefore, we studied Jinhua pig’s enterotype by using 16S rRNA high throughput sequencing, and then analyzed the interaction between enterotype and butyrate production. Results showed that we identified three ETs driven by discriminative genera dominated by Lactobacillus, Clostridium sensu stricto 1, and Bacteroides, respectively. Significant differences in the fecal contents of butyrate production and butyrate-producing bacteria were observed among ETs. These findings present a first overview of the enterotypes clustering in Jinhua pigs and provide new insights into the relationship between the different ETs and intestinal butyrate production.

Abstract

Gut microbiota is thought to play a crucial role in nutrient digestion for pigs, especially in processing indigestible polysaccharides in the diets to produce short-chain fatty acids (SCFAs). However, the link between microbiota community structure and phenotypic performances are poorly understood. In the present study, the fecal samples of 105 Jinhua pigs at 105 days of age were clustered into three enterotypes (ETs, ET1, ET2, and ET3) that are subpopulations of distinct bacterial community composition by using 16S rRNA high throughput sequencing. The α-diversity indices (the OTU number and Shannon index) were significantly different among the ETs (p < 0.001). At the genus level, the ET1 group was over-represented by Lactobacillus (17.49%) and Clostridium sensu stricto 1 (11.78%), the ET2 group was over-represented by Clostridium sensu stricto 1 (17.49%) and Bifidobacterium (11.78%), and the ET3 group was over-represented by Bacteroides (18.17%). Significant differences in the fecal contents of butyrate were observed among ETs, with the highest level detected in ET3 and the lowest in ET2 (p < 0.05). Consistently, more copies of the terminal genes for butyrate synthesis, butyrate kinase (Buk) and butyryl coenzyme A (CoA): acetate CoA transferase (But) were detected by qPCR in the fecal samples of the ET3 group as compared to other two groups (p < 0.05). In addition, of the two genes, But was demonstrated to be more relevant to the butyrate content (R = 0.7464) than Buk (R = 0.4905) by correlation analysis. In addition, based on the taxonomic analysis, we found that Faecalibacterium was the most relevant butyrate-producing genera with fecal butyrate contents in Jinhua pigs, followed by Butyricicoccus, Eubacterium, Butyricimonas, Blautia, and Anaerostipes, all of which showed significantly higher richness in ET3 than as compared to ET1 and ET2 (p < 0.05). Collectively, this work presents a first overview of the enterotypes clustering in Jinhua pigs and will help to unravel the functional implications of ETs for the pig’s phenotypic performance and nutrient metabolism.

Bacterial communities in PM2.5 and PM10 in broiler houses at different broiler growth stages in spring

The welfare and healthy growth of poultry under intensive feeding conditions are closely related to their living environment. In spring, the air quality considerably decreases due to reduced ventilation and aeration in cage systems, which influences the meat quality and health of broilers during normal growth stages. In this study, we analyzed the airborne bacterial communities in PM2.5 and PM10 in cage broiler houses at different broiler growth stages under intensive rearing conditions based on the high-throughput 16S rDNA sequencing technique. Our results revealed that PM2.5, PM10 and airborne microbes gradually increased during the broiler growth cycle in poultry houses. Some potential or opportunistic pathogens, including Acinetobacter, Pseudomonas, Enterococcus, Microbacterium, etc., were found in the broiler houses at different growth stages. Our study evaluated variations in the microbial communities in PM2.5 and PM10 and potential opportunistic pathogens during the growth cycle of broilers in poultry houses in the spring. Our findings may provide a basis for developing technologies for air quality control in caged poultry houses.

Transcriptome profiling of the liver among the prenatal and postnatal stages in chickens

The liver is an important organ that has pivotal functions in the synthesis of several vital proteins, the metabolism of various biologically useful materials, the detoxification of toxic substances, and immune defense. Most liver functions are not mature at a young age and many changes happen during postnatal liver development, which lead to differential functions of the liver at different developmental stages. However, the transcriptome details of what changes occur in the liver after birth and the molecular mechanisms for the regulation of the developmental process are not clearly known in chickens. Here, we used RNA-sequencing to analyze the transcriptome of chicken liver from the prenatal (at an embryonic day of 13) to the postnatal stages (at 5 wk and 42 wk of age). A total of approximately 161.17 Gb of raw data were obtained, with 4,127 putative and 539 differentially expressed lncRNAs, and with 13,949 putative and 6,370 differentially expressed mRNAs. Coexpression of lncRNAs-mRNAs in hepatic transcriptome analysis showed that the liver plays important roles in providing energy for organisms through the mitochondrial respiratory chain in chickens, meanwhile, acting as a crucial part of antioxidant stress. The developmental transcriptome date revealed that antioxidant defenses are likely to act on chicken embryo development and that significant functional changes during postnatal liver development are associated with the liver maturation of chickens. These results provide a timeline for the functional transcriptome transition from the prenatal to adult stages in chickens and will be helpful to reveal the underlying molecular mechanisms of liver development.

Ductus arteriosus aneurysm: Case report and review of the literature

We report the case of an infant boy born at 39 weeks and 5 days who presented a cleft lip and palate. During the assessment to detect associated malformations, cardiac auscultation revealed a systolic heart murmur. Echocardiography and subsequent thoracic computed tomography angiography identified an aneurysm of the ductus arteriosus. Ductus arteriosus aneurysm, a complicated form of patent ductus arteriosus, may not be as rare as once considered. A clear majority of ductus arteriosus aneurysms are asymptomatic and physiologically resolve after birth. Nevertheless, severe complications can occur, primarily during the postnatal period.

Levothyroxine monotherapy versus levothyroxine and selenium combination therapy in chronic lymphocytic thyroiditis

PURPOSE

New strategies are needed for prevention and treatment of chronic lymphocytic thyroiditis (CLT). This study aimed to assess whether combination of levothyroxine treatment and selenium (Se) supplementation results in improved therapeutic effects in CLT compared with levothyroxine monotherapy.

METHODS

An open-label, randomized controlled study was performed in 60 CLT patients assigned to two groups. Levothyroxine group (LT) patients (n = 24) received levothyroxine alone for 3 months; meanwhile, the combination (LTSS) group (n = 36) was administered levothyroxine with selenium yeast capsule. Blood selenium concentrations, anti-thyroid peroxidase (TPO) and anti-thyroglobulin (Tg) antibody levels, and inflammatory cytokine amounts were compared between both groups before and after treatment.

RESULTS

At baseline, similar values were obtained in both groups for all the parameters assessed (p > 0.05). After treatment, significantly increased blood selenium levels (µg/L) [90.05 (80.69, 107.76) vs. 39.64 (29.42, 51.10), p < 0.001] and decreased anti-TPO antibody (23.63 ± 9.31 vs. 32.00 ± 10.41%, p = 0.002), anti-Tg antibody (35.84 ± 15.21 vs. 45.47 ± 14.24%, p = 0.015) and IL-2 amounts (pg/mL) [159.29 (124.54, 189.70) vs. 226.48 (190.74, 266.56), p < 0.001] were observed in the LTSS group compared with the LT group post-treatment; meanwhile, similar IL-10 concentrations [23.14 (21.65, 28.56) pg/mL vs. 24.68 (21.71, 29.67) pg/mL] were obtained in both groups. Subgroup analysis of patients with hypothyroidism showed the same trend observed in the whole population; in patients with normal thyroid function, only Se and IL-2 amounts differed between the two treatment groups. Correlation analysis of of the indexes: in HT patients, the basal serum selenium concentration was positively correlated with TT₄ (r = 0.294, p < 0.05), significantly negatively correlated with TSH (r = -0.343, p < 0.01), and had no significant correlation with TT3 (p > 0.05).

CONCLUSIONS

These findings indicated that levothyroxine and selenium combination results in improved therapeutic effects than the levothyroxine monotherapy in preventing CLT progression.

Abstract 1538: A mouse model that mimics human MEN1 tumor is effective in preclinical neuroendocrine tumor therapeutics

Conditional knockout of Men1 in β cells leads to development of pituitary adenomas and pancreatic neuroendocrine tumors (PanNETs) by the age of eight to twelve months. This suggests that other events, like loss of additional mutations, may be required for development of tumors in the absence of MEN1. Since it was reported that mutations in genes of PI3K/mTOR pathway are found in human neuroendocrine tumors, we hypothesized that double deletion of PTEN and MEN1 may accelerate neuroendocrine tumorigenesis. Mice with double deletion of PTEN and MEN1 in β cells were produced by crosses among mice with Cre gene under the control of Rat Insulin promoter (Rip-Cre), floxed allele Men1 (Men1fl/fl), and Pten (Ptenfl/fl). Then mice with the genotype of Men1fl/fl Ptenfl/fl Rip-Cre were monitored for development of tumors. Consistent with our hypothesis, mice with conditional deletion of PTEN and MEN1 leads to fully developed PanNETs and pituitary adenomas by three to four months old, much earlier than that with Men1 deletion alone. These tumors resemble human MEN1 tumors at a histological and molecular level. Activation of phospho-AKT was observed in these tumors and Rapamycin treatments lead to delayed PanNETs and pituitary adenomas for at least two months. This mouse model (Men1fl/fl Ptenfl/fl Rip-Cre) directly supports that PI3K/mTOR pathway plays a critical role in neuroendocrine tumorigenesis, and also provides a platform to study new therapeutic opportunities for PanNETs and neuroendocrine tumors of the pituitary through the targeting of PI3K/mTOR pathway and MEN1 pathway. This model represents an important tool for studying the biology and preclinical therapeutics of human neuroendocrine tumors.

Citation Format: Chung Wong, Richard Clausen, Laura Tang, Christian Davidson, Evan Vosburgh, Arnold Levine, Eugenia Xu. A mouse model that mimics human MEN1 tumor is effective in preclinical neuroendocrine tumor therapeutics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1538. doi:10.1158/1538-7445.AM2017-1538

Abstract 267: Preclinical investigation of the HSP90 inhibitor, ganetespib, in combination with FDA-approved cytotoxic agents for their potential anti-tumor effects on human neuroendocrine tumors

The gastroenteropancreatic neuroendocrine tumor (GEP-NET) system is comprised of a heterogeneous group of tumors with increasing incidence. Current standard of care cytotoxic agents have limited efficacy, which necessitates the need for innovative therapeutic approaches. Heat shock protein 90 (HSP90) is overexpressed in a wide range of tumor types including human pancreatic neuroendocrine tumors (PanNETs). Ganetespib is a second-generation HSP90 inhibitor that is well tolerated in cancer patients (dosed into &gt;1500 patients) and is currently being evaluated in several investigator sponsored clinical trials including acute myeloid leukemia (AML), ovarian cancer, breast cancer, and other tumor types.

Here, we show that ganetespib inhibits the proliferation of NET cells and induces apoptosis in vitro with potency comparable to another second-generation HSP90 inhibitor (NVP-AUY922), but with potency two- to seven-fold more than first generation inhibitors (17-AAG, IPI-504) in BON-1, CM and H727 cell lines, and thirty-fold more in QGP-1 cell line. In mice bearing PanNET tumor xenografts, single agent ganetespib reduced the growth of tumors without signs of toxicity. Tumors from ganetespib treated animals demonstrated reduced phospho-AKT and phospho-ERK expression, and elevated HSP70 expression, supportive of exposures necessary for functional activity. In an effort to identify clinically meaningful agents that could further potentiate the antitumor activity of ganetespib, we performed in vitro combination screens evaluating proliferation in four NET cell lines with ganetespib and forty FDA approved anticancer agents. Ganetespib showed synergistic effects when combined with inhibitors of mTOR, topoisomerase I or II, or DNA synthesis. Results from our ongoing in vivo combination studies with ganetespib and these three classes of anticancer agents will be presented.

Citation Format: Chung Wong, Evan Vosburgh, Arnold Levine, David Proia, Eugenia Xu. Preclinical investigation of the HSP90 inhibitor, ganetespib, in combination with FDA-approved cytotoxic agents for their potential anti-tumor effects on human neuroendocrine tumors. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 267.

Higher mortality in patients with right hemispheric intracerebral haemorrhage: INTERACT1 and 2

BACKGROUND AND PURPOSE

Controversy exists over the prognostic significance of the affected hemisphere in stroke. We aimed to determine the relationship between laterality of acute intracerebral haemorrhage (ICH) and poor clinical outcomes.

METHODS

A subsidiary analysis of the INTERACT Pilot and INTERACT2 studies--randomised controlled trials of patients with spontaneous acute ICH with elevated systolic blood pressure (BP), randomly assigned to intensive (target systolic BP <140 mm Hg) or guideline-based (<180 mm Hg) BP management. Outcomes were the combined and separate end points of death and major disability (modified Rankin scale (mRS) scores of 3-6, 6 and 3-5, respectively) at 90 days.

RESULTS

A total of 2708 patients had supratentorial/hemispheric ICH and information on mRS at 90 days. Patients with right hemispheric ICH (1327, 49%) had a higher risk of death at 90 days compared to those with left hemispheric ICH after adjustment for potential confounding variables (OR, 1.77 (95% CI 1.33 to 2.37)). There were no differences between patients with right and left hemispheric ICH regarding the combined end point of death or major disability or major disability in the multivariable-adjusted models (1.07 (0.89 to 1.29) and 0.85 (0.72 to 1.01), respectively).

CONCLUSIONS

Right hemispheric lesion was associated with increased risk of death in patients with acute ICH. The laterality of the ICH does not appear to affect the level of disability in survivors.

TRIAL REGISTRATION NUMBER

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00226096 and NCT00716079.

PPM1D phosphatase, a target of p53 and RBM38 RNA-binding protein, inhibits p53 mRNA translation via dephosphorylation of RBM38

PPM1D phosphatase, also called wild-type p53-induced phosphatase 1 (Wip1), promotes tumor development by inactivating the p53 tumor suppressor pathway. RBM38 RNA-binding protein, also called RNPC1 and a target of p53, inhibits p53 mRNA translation, which can be reversed by GSK3 protein kinase via phosphorylation of RBM38 at serine 195. Here we showed that ectopic expression of RBM38 increases, whereas knockdown of RBM38 inhibits, PPM1D mRNA translation. Consistent with this, we found that RBM38 directly binds to PPM1D 3' untranslated region (3’UTR) and promotes expression of a heterologous reporter gene that carries PPM1D 3’UTR in a dose-dependent manner. Interestingly, we showed that PPM1D directly interacts with and dephosphorylates RBM38 at serine 195. Furthermore, we showed that PPM1D modulates p53 mRNA translation and p53-dependent growth suppression through dephosphorylation of RBM38. These findings provide evidence that the crosstalk between PPM1D and RBM38, both of which are targets and modulators of p53, plays a critical role in p53 expression and activity.

Histone deacetylase inhibitors suppress mutant p53 transcription via histone deacetylase 8

Mutation of the p53 gene is the most common genetic alteration in human cancer and contributes to malignant process by enhancing transformed properties of cells and resistance to anticancer therapy. Mutant p53 is often highly expressed in tumor cells at least, in part, due to its increased half-life. However, whether mutant p53 expression is regulated by other mechanisms in tumors is unclear. Here we found that histone deacetylase (HDAC) inhibitors suppress both wild-type and mutant p53 transcription in time- and dose-dependent manners. Consistent with this, the levels of wild-type and mutant p53 proteins are decreased upon treatment with HDAC inhibitors. Importantly, we found that upon knockdown of each class I HDAC, only HDAC8 knockdown leads to decreased expression of wild-type and mutant p53 proteins and transcripts. Conversely, we found that ectopic expression of wild-type, but not mutant HDAC8, leads to increased transcription of p53. Furthermore, we found that knockdown of HDAC8 results in reduced expression of HoxA5 and consequently, attenuated ability of HoxA5 to activate p53 transcription, which can be rescued by ectopic expression of HoxA5. Because of the fact that HDAC8 is required for expression of both wild-type and mutant p53, we found that targeted disruption of HDAC8 expression remarkably triggers proliferative defect in cells with a mutant, but not wild-type, p53. Together, our data uncover a regulatory mechanism of mutant p53 transcription via HDAC8 and suggest that HDAC inhibitors and especially HDAC8-targeting agents might be explored as an adjuvant for tumors carrying a mutant p53.

Significance of perihematomal edema in acute intracerebral hemorrhage: the INTERACT trial

BACKGROUND

Uncertainty surrounds the effects of cerebral edema on outcomes in intracerebral hemorrhage (ICH).

METHODS

We used data from the INTERACT trial to determine the predictors and prognostic significance of "perihematomal" edema over 72 hours after ICH. INTERACT included 404 patients with CT-confirmed ICH and elevated systolic blood pressure (BP) (150-220 mm Hg) who had the capacity to commence BP lowering treatment within 6 hours of ICH. Baseline and repeat CT (24 and 72 hours) were performed using standardized techniques, with digital images analyzed centrally. Predictors of growth in edema were determined using generalized estimating equations, and its effects on clinical outcomes were estimated using a logistic regression model.

RESULTS

Overall, 270 patients had 3 sequential CT scans available for analyses. At baseline, there was a highly significant correlation between hematoma and perihematomal edema volumes (r(2) = 0.45). Lower systolic BP and baseline hematoma volume were independently associated with absolute increase in perihematomal edema volume. History of hypertension, baseline hematoma volume, and earlier time from onset to CT were independently associated with relative increase in edema volume. Both absolute and relative increases in perihematomal edema growth were significantly associated with death or dependency at 90 days after adjustment for age, gender, and randomized treatment, but not when additionally adjusted for baseline hematoma volume.

CONCLUSIONS

The degree of, and growth in, perihematomal edema are strongly related to the size of the underlying hematoma of acute intracerebral hemorrhage, and do not appear to have a major independent effect in determining the outcome from this condition.

Presence of functional hyperpolarisation-activated cyclic nucleotide-gated channels in clonal alpha cell lines and rat islet alpha cells

AIMS/HYPOTHESIS

The hyperpolarisation-activated cyclic nucleotide-gated (HCN) channels, discovered initially in cardiac and neuronal cells, mediate the inward pacemaker current (I (f) or I (h)). Recently, we have demonstrated the presence of HCN channels in pancreatic beta cells. Here, we aim to examine the presence and function of HCN channels in glucagon-secreting alpha cells.

METHODS

RT-PCR and immunocytochemistry were used to examine the presence of HCN channels in alpha cells. Whole-cell patch-clamp, calcium imaging and glucagon secretion experiments were performed to explore the function of HCN channels in alpha cells.

RESULTS

HCN transcripts and proteins were detected in alpha-TC6 cells and dispersed rat alpha cells. Patch-clamp recording showed hyperpolarisation-activated currents in alpha-TC6 cells, which could be blocked by HCN channel inhibitor ZD7288. Glucagon secretion RIA studies demonstrated that at both low and high glucose concentrations (2 and 20 mmol/l), ZD7288 significantly enhanced glucagon secretion in alpha-TC6 and IN-R1-G9 cell lines. Conversely, activation of HCN channels by lamotrigine significantly suppressed glucagon secretion at the low glucose concentration. Calcium imaging studies showed that blockade of HCN channels by ZD7288 significantly increased intracellular calcium in alpha-TC6 cells, while lamotrigine or the Na(+) channel blocker tetrodotoxin suppressed the effect of ZD7288 on intracellular calcium. Furthermore, we found the HCN channel inhibitors ZD7288 and cilobradine both significantly increased glucagon secretion from rat islets.

CONCLUSIONS/INTERPRETATION

These results suggest a potential role for HCN channels in regulation of glucagon secretion via modulating Ca(2+) and Na(+) channel activities.

Polymorphisms of the lipoprotein lipase gene are associated with atherosclerotic cerebral infarction in the Chinese

BACKGROUND

Lipoprotein lipase (LPL), which plays an essential role in plasma lipoprotein metabolism and transportation, appears to be a risk factor for ischemic vascular diseases. Several studies have recently reported the presence of relationship between HindIII, PvuII, Ser447Ter (C-->G) polymorphisms of LPL and ischemic vascular diseases.

PURPOSE

We first studied the relationship between LPL polymorphisms and the risk of atherosclerotic cerebral infarction (CI) by detecting the frequencies of LPL HindIII, PvuII and Ser447Ter genotypes and combined genotypes in the Chinese.

METHODS

We recruited 185 CI patients, confirmed by cranial computed tomography or magnetic resonance imaging/angiography, or both, and 186 control subjects. Polymerase chain reaction-restriction fragment length polymorphisms technique was used to detect HindIII, PvuII and Ser447Ter polymorphisms of the LPL gene.

RESULTS

The frequencies of the H+H+ genotype and H+ allele did not differ between CI and control groups. The frequencies of the P+P+ genotype and P+ allele gene were significantly higher in the CI group (P=0.040, P=0.015). The frequencies of CG+GG genotype and G allele were lower in the CI group (P<0.001, P<0.001). In the CI group, the individuals with P+P+ genotype had a significantly higher level of plasma triglyceride (TG) and a lower level of plasma high density lipoprotein cholesterol (HDL-c). CG+GG genotypes were correlated with significantly higher levels of plasma total cholesterol (TC), HDL-c and low density lipoprotein cholesterol (LDL-c) in the CI group. The frequencies of H+/C and P+/C combined genotypes were higher in the CI group than in controls (P<0.001, P<0.001). The frequency of H+/P+/C combined genotype was significantly higher in the CI group than in controls (P<0.001).

CONCLUSIONS

Our study suggests that PvuII and Ser447Ter polymorphisms are associated with lipid profile and CI.

Activin receptor-like kinase 7 induces apoptosis of pancreatic beta cells and beta cell lines

AIMS/HYPOTHESIS

Activin receptor-like kinase 7 (ALK7), a member of the type I receptor serine/threonine kinases of the TGF-beta superfamily, was recently reported to regulate cell proliferation and apoptosis. We hypothesised that ALK7 may play a role in modulating pancreatic beta cell proliferation and/or apoptosis.

METHODS

We detected ALK7 expression in beta cells using RT-PCR, immunostaining and western blotting. Constitutively active, dominant negative or wild-type ALK7 was introduced into beta cells using adenoviral delivery. Proliferation was assessed using (3)H-thymidine incorporation and apoptosis was quantified using terminal deoxynucleotidyl transferase biotin-dUTP nick end labelling detection, DNA degradation analysis and caspase-3 assays.

RESULTS

Induction of constitutively active ALK7 in beta cells resulted in growth inhibition and enhanced apoptosis; no effect was seen with INS-1 cells expressing wild-type or dominant negative ALK7. Elevated glucose concentrations and fatty acid (palmitate) markedly increased expression levels of ALK7 transcripts and proteins in INS-1 and rat islets and increased beta cell apoptosis. Activation of ALK7 increased Smad2 phosphorylation, reduced protein kinase B (Akt) kinase activity and was associated with increased levels of the bioactive forms of caspase-3, whereas co-expression of constitutively active ALK7 with dominant negative Smad2 or constitutively active Akt significantly diminished ALK7-induced growth inhibition and apoptosis in INS-1 cells. Although overexpression of constitutively active Akt significantly reduced ALK7-induced growth inhibition and ALK7-enhanced beta cell apoptosis, ALK7-stimulated Smad2 phosphorylation was not affected.

CONCLUSIONS/INTERPRETATION

These results suggest that the pancreatic beta cell apoptosis induced by ALK7 activation occurs via the activation of two distinct downstream pathways: the suppression of Akt activation and the activation of the Smad2-caspase-3 cascade.

Glucagon-like peptide-1 regulates proliferation and apoptosis via activation of protein kinase B in pancreatic INS-1 beta cells

AIMS/HYPOTHESIS

The incretin hormone glucagon-like peptide-1 augments islet cell mass in vivo by increasing proliferation and decreasing apoptosis of the beta cells. However, the signalling pathways that mediate these effects are mostly unknown. Using a clonal rat pancreatic beta cell line (INS-1), we examined the role of protein kinase B in mediating beta-cell growth and survival stimulated by glucagon-like peptide-1.

METHODS

Immunoblot analysis was used to detect active (phospho-) and total protein kinase B. Proliferation was assessed using (3)H-thymidine incorporation, while apoptosis was quantitated using 4'-6-diamidino-2-phenylindole staining and APO percentage apoptosis assay. Kinase-dead and wild-type protein kinase B was introduced into cells using adenoviral vectors.

RESULTS

Glucagon-like peptide-1 rapidly activated protein kinase B in INS-1 cells (by 2.7+/-0.7-fold, p<0.05). This effect was completely abrogated by inhibition, with wortmannin, of the upstream activator of protein kinase B, phosphatidylinositol-3-kinase. Glucagon-like peptide-1 also stimulated INS-1 cell proliferation in a dose-dependent manner (by 1.8+/-0.5-fold at 10(-7) mol/l, p<0.01), and inhibited staurosporine-induced apoptosis (by 69+/-12%, p<0.05). Both of these effects were also prevented by wortmannin treatment. Ablation of protein kinase B by adenovirus-mediated overexpression of the kinase-dead form of protein kinase Balpha prevented protein kinase B phosphorylation and completely abrogated both cellular proliferation ( p<0.05) and protection from drug-induced cellular death ( p<0.01) induced by glucagon-like peptide-1.

CONCLUSIONS/INTERPRETATION

These results identify protein kinase B as an essential mediator linking the glucagon-like peptide-1 signal to the intracellular machinery that modulates beta-cell growth and survival.

[Application of CT virtual bronchoscope in foreign-body in children's bronchus]

OBJECTIVE

To evaluate the clinical application of CT virtual bronchoscope in foreign-body in bonchus.

METHOD

The CT virtual bronchoscope were used in 21 cases with foreign-body in bronchus, all the images and reports were compared with the actual bronchoscopy.

RESULT

The reports and images of CT virtual bronchoscope are very agreed with that of actual bronchoscopy.

CONCLUSION

CT virtual bronchoscope is a very good complemental method in preoperative diagnosis of foreign-body in bronchus.

[Atypical pheochromocytoma]

OBJECTIVE

To improve the diagnosis and treatment of atypical pheochromocytoma.

METHODS

51 cases of pheochromocytoma were treated from July 1985 to August 1998.

RESULTS

Of the 51 cases, 19 were atypical, and were characterized by silent tumor, pheochromocytoma in pregnancy, bilateral tumor, extraadrenal tumor, malignant tumor, and recurrent tumor. Open operation was performed for all kinds of cases in accordance with their special characteristics.

CONCLUSIONS

Surgical extirpation is the only means for the treatment of atypical pheochromocytoma and meticulous perioperative management is essential.

[Long-term results of intravesical N-CWS instillation to prevent recurrence after surgery for bladder cancer]

OBJECTIVE

To evaluate the long term results of intravesical nocardia rubre cell wall skeleton instillation to prevent recurrence after surgery for bladder cancer.

METHODS

A randomized and placedo-controlled trial on intravesical N-CWS instillation versus mitomycin-C(MMC) therapy for recurrence prevention in postopenative bladder cancer patients was carried out.

RESULTS

Fourty-five patients were treated with N-CWS with 39 followed for 12 to 60 months. Thirteen patients developed recurrence. The 1-year tumor free survival rate was 87.2% and that at 5 years was 66.7%. Thirty patients as treated with MMC serving as controll with 25 followed for the same duration, twelve patients developed recurrence. The 1-year tumor free survival rate was 84% and that at 5 years was 52%. The results indicate that N-CWS gave better results with rare and milder side effects.

CONCLUSION

N-CWS is believed to be one of the effective drugs in preventing bladder cancer recurrence after surgery.

[Evaluation of combined test of sequential fecal occult blood and albumin in the screening of colorectal neoplasms]

Fecal albumin test was developed and the combined use of sequential occult blood test and albumin test (SA) was evaluated and compared with sequential fecal occult blood test (S) in 365 cases diagnosed clinically and pathologically and in 883 asymptomatic individuals. In the former group, the sensitivity of detection of colorectal cancer was: 50.7% (37/73) with S and 87.7% (64/73) with SA (P < 0.001), and that of the adenoma was: 8.1% (6/74) with S and 36.5% (27/74) with SA (P < 0.001). In the latter group 2 of 3 cancer patients were detected with S while all with SA, and the detection rate of adenoma was: 4.7% (4/85) with S and 42.4% (36/85) with SA (P < 0.001) it is suggested that the additional use of fecal albumin test is of help in detecting precancerous inflammatory bowel lesions without bleeding.

Case-control study of cigarette smoking and primary hepatoma in an aflatoxin-endemic region of China: a protective effect

Aflatoxin is believed to be a major causative agent in the high incidence of primary liver cancer seen in certain regions of the world. In Fujian Province, an aflatoxin-endemic region of China, we compared the cigarette smoking habits of 200 primary hepatoma patients with those of 200 matched nonhepatoma controls. We excluded from our study all individuals with evidence of hepatitis B virus serum antigen and/or alcoholic cirrhosis. Interestingly, two groups of hepatoma patients could be discerned. In patients more than 50 years of age, a significantly higher number of cases of primary hepatoma was found among nonsmokers than smokers (odds ratio = 2.06; 95% confidence interval = 1.32-3.20). In patients less than 50 years of age, this difference was not seen. Previous studies in the rat, mouse and duck had suggested that agents present in cigarette smoke might induce a cytochrome P450-mediated detoxication pathway, leading to protection against aflatoxin-induced primary liver cancer. Our clinical data in the present study are therefore consistent with the previous laboratory animal experiments.