bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nicotine Acutely Induces Hyperglycemia and Hepatic Steatosis by Altering the Sympathetic Outflow
Authors: Ruiz Henry h. , Peddibhotla Swetha , Ramalingam Latha , Moustaid‐Moussa Naima , Shin Andrew C. 
Published: June 2021

Cigarette smoking is a major risk factor for cardiovascular diseases, cancers, and metabolic syndrome. Studies have shown that smoking induces insulin resistance and hyperglycemia. Nicotine, the major constituent of cigarette, is thought to be responsible for the impaired insulin sensitivity and glycemic control. However, the underlying mechanisms are poorly understood. To first examine the acute effects of nicotine on glucose metabolism, we injected chow‐fed mice with either saline or nicotine (1.5mg/kg) intraperitoneally. Interestingly, a single injection of nicotine increased blood glucose by 50% within the first 15 min that lasted at least for 1h. Further, treatment with nicotine led to impaired glucose tolerance compared to controls. Lipolysis from white adipose tissue (WAT), primarily driven by the sympathetic nervous system (SNS), can provide glucogenic substrates to liver to promote gluconeogenesis. However, mice unable to mobilize lipids from WAT due to lack of adipose‐specific adipose triglyceride lipase (ATGL) similarly elevated blood glucose following nicotine injection. On the other hand, deletion of tyrosine hydroxylase (the rate‐limiting enzyme for catecholamine synthesis) only in the periphery completely abolished the rise of glucose in nicotine group, suggesting that the sympathetic drive to peripheral organs other than WAT may be responsible for nicotine‐induced hyperglycemia. Indeed, nicotine injection increased the sympathetic outflow to liver by 20%, but not WAT, as measured by norepinephrine (NE) concentrations 1h after injection. Hepatic glycogen content was markedly reduced in nicotine‐treated animals, probably due to the SNS‐driven glycogenolysis in liver. Surprisingly, a single nicotine injection in high‐fat (HF)‐fed obese mice not only induced severe hyperglycemia, but also hepatic steatosis compared to saline‐treated HF controls. NE content in liver was significantly lower (>two‐fold) in nicotine‐treated HF group compared to HF control group. While the reasons are not clear, we speculate that unlike in chow‐fed mice, nicotine in HF‐fed mice may suppress the sympathetic drive to liver resulting in less beta oxidation and/or reduced triglyceride secretion, hence fatty liver, whereas it may raise the sympathetic outflow to WAT to increase lipolysis that in turn can promote hepatic gluconeogenesis, resulting in hyperglycemia.Support or Funding InformationNIH K01 DK099463Presidents' Collaborative Research Initiative Grant, Texas Tech University SystemThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
NOD‐like Receptors: Novel Regulators of the Microbiota‐Gut‐Brain Axis in Mice
Authors: Pusceddu Matteo M. , Wong Kyle Akio , Stokes Patricia , Sladek Jessica A. , Gareau Melanie G. 
Published: June 2021

BackgroundThe crosstalk between the gut and the brain has revealed a complex communication system responsible for maintaining a proper gastrointestinal (GI) homeostasis as well as affect emotional mood and cognitive functions. The immune system, which is recognized to maintain the symbiotic relationship between the host and the microbiota, plays a pivotal role in the regulation of the microbiota‐gut‐brain (MGB) axis. Specifically, nucleotide binding oligomerization domain (Nod)‐like receptors (NLR), which sense bacterial pathogens and initiate the innate immune response, are essential in maintaining GI homeostasis. Moreover, their expression in the brain implicates them as potential prime mediators of the MGB axis. The hypothalamic‐pituitary adrenal (HPA) axis is a critical component of the stress response, and has been shown to be closely correlated to the MGB axis.HypothesisWe hypothesized that deficiency in NLRs, (i.e. Nod1/Nod2), will dysregulate the MGB axis, including mood, cognitive behavior, and GI physiology.MethodsAdult (6–8 weeks of age) male and female Nod1/Nod2 double knockout (NodDKO) and wild type (WT; C57Bl/6) mice were utilized. Mice were subjected to behavioral tests (novel object recognition [NOR] task, light/dark box, open field test) following exposure to an acute stress (water avoidance stress [WAS]) to assess recognition memory, anxiety‐like behavior, and general health, respectively.ResultsDeletion of Nod1 and Nod2 receptors reduced cognitive performance in both male and female mice following WAS compared to WT controls. In contrast, only male NodDKO mice exhibited anxiety‐like behavior vs. WT controls. These changes in behavior were accompanied by altered mRNA expression levels of genes for stress (↓corticotropin releasing factor receptor [CRFR]1; ↑CRFR2), cognition (↑brain‐derived neurotropic factor [BDNF]) and inflammation (↑tumor necrosis factor [TNF]α; ↓interleukin [IL]10) in the hippocampus and prefrontal cortex of NodDKO mice in a sexually dimorphic manner. Stress‐induced impairment in colonic physiology (↑short circuit current [Isc] and ↑conductance [G]) were also observed in NodDKO mice in addition to altered mRNA expression for pro‐inflammatory cytokines (↑IL6) and antimicrobial peptides (↓RegIIIγ).ConclusionOur study suggests that innate immune NLRs are important for the regulation of mood, cognitive memory and GI physiology in response to acute stress in part via an impaired HPA axis, demonstrating a critical role in the maintenance of the MGB axis and homeostasis.Support or Funding InformationThis work was funded by NIH 1R01AT009365‐01 (MGG), 5R21MH108154‐01 (MGG).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
An apple a day: pectin is an important source of formate in the rat.
Authors: Brosnan John T. , Clow Kathy A. , Brosnan Margaret E. 
Published: June 2021

Since formate plays an important role in one‐carbon metabolism we examined the potential role of pectin as a source of formate. Rats were fed purified, AIN 93‐based diets in which the source of fibre was either 5% pectin (PF rats) or 5% cellulose (CF rats). The intestinal formate content was much higher in the PF rats than in the CF rats, with ileum>caecum> large intestine. Formate was primarily found in intestinal contents rather than in tissue. The gut output and the hepatic uptake of methanol were significantly elevated in the PF rats, as was the hepatic uptake of formate. Both plasma formate and methanol were markedly higher in PF rats. Chow‐fed rats, treated with a mixture of antibiotics (vancomycin, gentamycin, rifampin) for 7 days, had markedly decreased formate levels and a complete suppression of intestinal formate output compared to chow‐fed rats without antibiotics. Hepatic uptake of formate continued in the antibiotic‐treated animals. There is a requirement for the intestinal microbiome in the maintenance of normal circulating formate levels.Pectins are polysaccharides, rich in galacturonic acid of which approximately 80% of the carboxyl groups are esterified with methanol. These methyl groups may be removed during digestion by means of a methylesterase. We suggest that methanol, so produced, can give rise to substantial quantities of formate which becomes available to rat tissues as a source of one‐carbon groups. These findings are also relevant to experiments with cobalamin‐deficient animals in which pectin is commonly used as a cobalamin‐binding agent.Support or Funding InformationSupported by CIHRThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Computational Design and Experimental Evaluation of Novel Perezone Derivates as Anticancer Agents
Authors: Rodríguez Maricarmen Hernández , Sánchez Pablo Mendoza , Jimenez Elvía Mera , Vázquez María Inés Nicolás , Miranda‐Ruvalcaba René 
Published: June 2021

Cancer is one of the leading causes of morbidity and mortality worldwide. The disease is characterized by uncontrolled growth and proliferation of abnormal cells with a high probability to develop metastasis. Although conventional treatments are effective, these methods exert severe side effects due to affect normal cells. For this reason, the development of compounds that target dysregulated proteins in cancer results in a research field of interest. Recently, it was demonstrated that perezone and its synthetic isomer; isoperezone are capable to activate the apoptotic pathway, however, the protein target which explains its pro‐apoptotic activity is unknown. For this reason, the aim of this study was to perform computational studies to propose the protein target to perezone and isoperezone to design and evaluate novel perezone derivates. Proteins regulators of apoptosis pathway which have been dysregulated in cancer were selected to perform docking studies and molecular dynamic simulations with perezone and isoperezone. The proteins murine doble minute 2 (MDM2) and Poly [ADP‐ribose] polymerase 1 (PARP‐1) were selected. A family of ester derivates was submitted to docking simulations with MDM2 and PARP1 proteins to select the most promising compounds. According to these results, the compound 4 (Isoperezone‐angelate; MDM2 ΔG=− 7.65 Kcal/mol and PARP1 ΔG=−9.67 Kcal/mol) and compound 12 (monoangelate of hidroxiperezone; MDM2 ΔG=−8.92 Kcal/mol and PARP1 ΔG= −8.48 Kcal/mol) represent the best candidates due to its high affinity to both proteins, these compounds were synthesized, purified and evaluated in vitro as an anti‐cancer agent against K562 and MCF‐7 breast cancer cell lines. Compound 4 (K562 IC50=4.4 μM and MCF‐7 IC50=0.12 μM) and compound 12 (K562 IC50=2.1 μM and MCF‐7 IC50= 5.2 μM) showed a better potency than perezone (K562 IC50=9.22 μM and MCF‐7 IC50=329.2 μM) on cancer cells. In conclusion, compound 4 and 12 are examples of drugs designed in silico that show improved biological properties against human cancer cell lines.Support or Funding InformationUNAM‐DGAPA Posdoctoral Fellowship of MHR, LANCAD‐UNAM‐DGTIC‐165.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Utilization of Semi‐Solid Agar Inoculation in Microbial Co‐Culture: A Novel Protocol for Antibiotic Discovery
Authors: Slaughter Syara I. , Cadet Valerie E. 
Published: June 2021

Microbial co‐culture has many important applications, not least of which being the identification of novel antibiotic factors. However, current co‐culture methods including culture overlay utilizing either the spread or streak plate methods, risk contamination of samples during isolation attempts. Since the bacteria must occupy the same physical space to obtain nutrients, mixed cultures are often obtained during selection of colonies of interest. Semi‐solid agar inoculation co‐culture is an innovative culturing technique which aims to physically separate co‐cultured bacteria to aid in the isolation process. Semi‐solid tryptic soy agar (TSA) with a 1% agar concentration was shown to gellify without difficulty and was able to withstand a variety of culturing methods including lawn culturing, streaking, and point inoculation. Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus, and environmental soil microbes inoculated into the semi‐solid agar were able to proliferate and disseminate throughout the entirety of the plate without difficulty. When cultured on top of the inoculated agar, the previously mentioned bacteria grew as expected. Additionally, the resultant colonies exhibited comparable morphology to the same bacteria grown on non‐inoculated agar at typical agar concentration. Due to the ability of secreted factors to diffuse throughout the semi‐solid agar, interactions between the microorganisms, or lack thereof, were readily seen. This technique could prove especially powerful in increasing bacterial yield from environmental samples and aid in antibiotic research and discovery for antibiotic‐resistant priority pathogens (ARPPs).Support or Funding InformationFunded by Divison of Research, Georgia Campus‐Philadelphia College of Osteopathic Medicine.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
PINX1 promotes malignant transformation of thyroid carcinomas through AKT, MAPK, and β‐catenin signaling activation
Authors: Kang JiHoon , Park Sunhoo , Myung Jae Kyung 
Published: June 2021

Although a large proportion of thyroid cancers, specifically papillary thyroid carcinomas (PTCs), generally show indolent biological behavior, some patients present with aggressive clinical manifestations such as distant metastasis and recurrence. It was also shown that PTC could be progressed to more malignant subtype, anaplastic thyroid carcinomas (ATCs), through specific gene mutation and signaling activation. However, the key modulators regulating malignant transformation of PTCs still remain to be identified. In the current study, we found that PIN2/TERF1 interacting telomerase inhibitor 1 (PINX1) was highly expressed in ATC patient tissues and cell lines compared to PTC patient tissues and cell lines. To investigate the effects of PINX1 on proliferation and migration, we checked colony formation capacity, cell migration, and EMT markers expression after regulation of PINX1 expression. Knockout of PINX1 using specific siRNAs decreases cell proliferation and inhibits cell cycle progression in ATC cell lines, whereas PINX1 gene transfection increases cell proliferation and promotes cell cycle progression in PTC cell lines. Moreover, downregulation of PINX1 in ATC cells reduces cell migration and EMT‐related markers expression, while upregulation of PINX1 in PTC cells increases cell migration and EMT‐related markers expression. To verify whether PINX1 is involved in anaplastic progression, we investigated AKT, MAPK, and β‐catenin signaling activation which were reported to play major roles in anaplastic progression of thyroid carcinomas. Decrease of PINX1 expression repressed the phosphorylation of AKT, p38, and ERK and reduced the expression level of β‐catenin in ATC cell lines. Moreover, increase of PINX1 expression promoted the phosphorylation of AKT, p38, and ERK and upregulated the expression level of β‐catenin in PTC cell lines. These results showed that PINX1 might promote cell proliferation, migration and anaplastic progression of thyroid carcinomas through the activation of AKT, MAPK, and β‐catenin signaling pathways.Support or Funding InformationThis study was supported by a grant from the Korea Institute of Radiological and Medical Sciences (KIRAMS), funded by the Ministry of Science and ICT (MSIT), Republic of Korea. (No. 50476‐2018)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
An active‐like Src conformation explains its dynamic regulation
Authors: Ahuja Lalima G , Meng Yilin , Kornev Alexandr P , Roux Benoit , Taylor Susan 
Published: June 2021

Biological signaling by protein kinases plays an essential role in cellular function. The switch between inactive and active protein kinase conformations is central to their regulation. The active conformations of protein kinases are triggered and maintained by various post‐translational modifications. The inactive conformation of Src tyrosine kinase has a non‐phosphorylated activation loop and a rolled‐out αC helix. The R‐spine at the Src kinase core is disassembled via the RS3 residue when the αC helix is disengaged. Maneuvering of the C‐spine is crucial for obtaining a pseudokinase conformation of Src that could be crucial for exploring its scaffolding functions. Our Umbrella sampling methods allow for mapping the conformational landscape of the Src kinase domain and characterizing four defining states; the inactive, active conformations and two intermediates. Mutation of the C‐spine V281F allows for the closing of the two kinase lobes in the absence of ATP. An allosteric region at the β3‐αC loop allows for engaging the αC helix and the RS3 residue of the R‐spine via the L297F mutation. The L297F/ V281F double mutant allows for stabilization of a unique catalytically dead kinase conformation in the active‐like state. These studies allow for exploration of active‐like Src kinase states that define both the underlying kinase activation switch and the dynamic allostery in the molecular communication at the kinase core.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Downregulation of autophagy‐regulatory proteins contributes to induction of replicative senescence in Hs68 cells
Authors: Lee Michael , Hwang Sung‐Hee 
Published: June 2021

Autophagy is reported to be involved in preventing cellular senescence. However, the extent to which autophagy contributes to senescence is presently unclear. Here, we investigated the role of autophagy in replicative senescence using Hs68 human foreskin fibroblasts. Human foreskin fibroblasts, Hs68 cells, at an initial passage of 15 were serially cultured for several months until they reached cellular senescence. Induction of replicative senescence in aged cells (at passage 40) was confirmed by senescence‐associated β‐galactosidase (SA‐β‐gal) activity that represents a sensitive and reliable marker for quantifying senescent cells. The expression level of p53, which is required for induction of senescence, p53 expression continued to increase up to passage 34. Notably, the gradual decrease in basal autophagy coincided with replicative senescence induction as determined by LC3 conversion assay. However, despite decreased basal autophagic activity in senescent cells, autophagy inducers could induce autophagy in senescent cells. RT‐PCR analysis of 11 autophagy‐related genes revealed that the decreased basal autophagy in senescent cells might be due to the downregulation of autophagy‐regulatory proteins, but not autophagy machinery components. Moreover, the senescence phenotype was not induced in the cells in which rapamycin was added to the culture to continuously induce autophagy from passage 29 until passage 40. Together, our findings suggest that reduced basal autophagy levels due to downregulation of autophagy‐regulatory proteins may be the mechanism underlying replicative senescence in Hs68 cells. In addition, alterations in autophagic activity offer an additional target for therapeutics that limit the process of senescence.Support or Funding InformationSupported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2016R1D1A1B03930193)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Vitamin D Stimulates Serotonin Production via Induction of the Tryptophan Hydroxylase 2 Isoform in B14 Rat Medullary Neurons
Authors: Lucas Daniel A. , Sabir Marya S. , Mallick Sanchita , Whitfield G. Kerr , Haussler Mark R. , Jurutka Peter W. 
Published: June 2021

The active form of vitamin D3, 1,25‐dihydroxyvitamin D (1,25D), and serotonin (5‐HT) are postulated to play significant roles in abnormal social behavior associated with psychological conditions including autism spectrum disorders (ASDs) and depression. Moreover, we have observed that 1,25D regulates synthesis of two isoforms of tryptophan hydroxylase (TPH), the rate‐limiting enzyme in the 5‐HT biosynthetic pathway, including induction of the tryptophan hydroxylase 2 (TPH2) gene in the central nervous system (CNS) and suppression of tryptophan hydroxylase 1 (TPH1) expression in some peripheral tissues. Interestingly, major characteristics associated with autism may include low concentrations of serotonin in the CNS and elevated levels of serotonin in the periphery. Thus, in addition to assessing the effect of 1,25D on TPH gene expression, we also examined, for the first time, the ability of 1,25D to stimulate production of 5‐HT in neuronal cells. Rat serotonergic medullary cells (RN46A‐B14; B‐14) were cultured to confluency and plated in six‐well plates. After allowing cells to attach in the plates overnight, the cells were cultured in differentiation medium, followed by treatment of differentiated B‐14 cells with ethanol vehicle or 10−8 M 1,25D. At time zero, a 200 μL sample of media from each well was collected to serve as a baseline for 5‐HT concentration. The cells were then incubated over the next three days, and additional 200 μL samples were collected from each well at the 24‐, 48‐ and 72‐hour time points. A 5‐HT ELISA assay was then conducted using the collected samples. The results of the ELISA revealed a statistically significant increase (57%, p < 0.05) in 5‐HT production following treatment with 1,25D for 24 hours versus vehicle, with subsequently larger percent‐increases in 5‐HT synthesis observed at 48 and 72 hours (64% and 103%, respectively, p < 0.05). These results suggest that 1,25D stimulates the production of serotonin, likely through the induction of the neuronal TPH2 gene, and the time‐course of this effect appears to lag behind the induction of TPH mRNA which peaks at 24 hours. In summary, this study illuminates a novel coordinated biochemical and regulatory interaction between two neuromodulators, vitamin D and serotonin, thereby identifying a potential connection between serum vitamin D levels and the occurrence of psychiatric disorders commonly linked to an imbalance in CNS serotonin production, including autism and depression.Support or Funding InformationThis project was funded by the New College of Interdisciplinary Arts and Sciences at Arizona State University and the National Institutes of Health.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.