bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Ethanol and Oxidized Metabolites of Linoleic Acid on Caco‐2 cell Model of Intestinal Epithelial Barrier
Authors: Liu Huilin , Joshi‐Barve Swati , Barve Shirish , McClain Craig , Ramsden Christopher , Kirpich Irina 
Published: June 2021

IntroductionThe intestinal epithelial barrier plays a critical role in host defense against luminal pathogens. Ethanol (EtOH) and dietary components may alter barrier integrity resulting in increased intestinal permeability, endotoxemia and multi‐organ pathology. The aim of the present study was to evaluate the effects of EtOH, linoleic acid (LA, a major unsaturated fatty acid in the Western diet), and its bioactive oxidized metabolites (OXLAMs) on Caco‐2 cells, an in vitro model of intestinal epithelial barrier.Materials and MethodsCaco‐2 cell monolayers were exposed to LA, OXLAMs (9‐and 13‐hydroxyoctadecadienoic acids, HODEs) and/or EtOH. Transepithelial resistance (TEER), expression of intestinal tight junction (TJ) proteins, and pro‐inflammatory response were evaluated.ResultsDecreased TEER in response to EtOH, LA, and multiple HODE isoforms was observed after 24 hours of exposure. Combined effects of EtOH and 13(S)HODE or +13HODE on TEER were greater compared to EtOH and 9(S)HODE or +9HODE. The combination of EtOH and 13(S)HODE or +13HODE resulted in greater down‐regulation of TJ proteins and increased expression of TNF‐α, IL‐1β, and IL‐6 mRNA compared to EtOH alone.ConclusionCombined exposure of EtOH and OXLAMs exacerbates disruption of intestinal barrier integrity and pro‐inflammatory response in Caco‐2 cells.
The identification of novel modulators for the SIRT‐6 protein
Authors: Moaddel Ruin , Singh Nagendra , Ravichandran Sarangan , Norton Darrell D. , Fugmann Sebastian 
Published: June 2021

ObjectiveSIRT6 has been proposed as a potential therapeutic target for metabolic disorders and the prevention of age‐associated diseases. The aim of this study was to develop a screening method for the identification of novel modulators of SIRT6 from a natural plant extract.MethodsSIRT6 was immobilized onto the surface of magnetic beads (SIRT6‐MB), and the enzymatic activity was measured. Subsequently, SIRT6 was immobilized onto the surface of an open tubular capillary and characterized by frontal chromatography.ResultsThe identification of quercetin, vitexin as inhibitors from Trigonella foenum‐graecum was carried out. Structurally related flavonoids were then tested for their activity on SIRT6. In addition to obtaining their binding activity, they were also ranked based on their ability to displace quercetin. Further, preliminary results with ligand fishing experiments using the SIRT6‐MB suggest the identification of additional compounds from fenugreek seed extract with activity at the SIRT6‐protein.ConclusionThe SIRT6‐MBs were successfully used for the identification of an active ligand from a botanical matrix, which sets the basis for identification of SIRT6 modulators from plant extracts.
Design of complement inhibitors that block IgG‐induced C3 activation through its properdin binding site
Authors: Petitclerc Eric , Mercier Virginie , Drouin Mathieu , Simard Carl , Aubin Eric 
Published: June 2021

Complement dysregulation appears important in the etiology of many autoimmune and inflammatory diseases. IVIG, the C3 inhibitor compstatin and the humanized anti‐C5 antibody Eculizumab modulate complement through direct inhibition of protein activation. In an effort to decipher the mechanisms by which protein‐protein interactions modulate the activation of the complement protein C3 through the classical and alternate cascade, we investigated whether small peptides could interfere with the specific interaction between C3 and properdin. First, we verified that a 34 amino acid peptide, derived from C3, inhibits its interaction with properdin but cannot displace either C3 or properdin from aggregated IgG. Interestingly, a 9‐mer peptide that span within the original 34 amino acids is able to replicate the effect of the 34‐mer toward C3‐properdin interaction. Of utmost interest, further experiments demonstrate that this 9‐mer is also able to inhibit the binding of C3 to IgG. On a molar basis, the active peptide is as powerful as IVIG and an optimized cyclic peptide that inhibits the activation of C3, compstatin. Further analyses demonstrate that the active 9‐mer peptide is able to inhibit complement activation in sensitized red blood cells (SRBC) hemolysis assays. Altogether, these results showed that inhibitory effect of IVIG on in vitro complement activation can be mimicked, at least in part, by a 9‐mer peptide. A quantitative structure‐activity relationship (QSAR) was performed using the minimal active 9‐mer peptide. Linearity and the C‐terminus amino acids were shown to be critical for its activity, and further length reduction of the peptide strongly reduces its activity.We have identified a potent complement inhibitor with potential therapeutic applications in inflammatory and autoimmune diseases.
Blunted hypertensive response to Ang II infusion in IFN‐g knockout mice: molecular mechanisms
Authors: Kamat Nikhil V , Fletcher Nicholas K.H. , Thabet Saleem , Harrison David G. , McDonough Alicia A 
Published: June 2021

The hypertensive response to AngII infusion is blunted in CD8−/− and IFNg −/− mice.AIMDetermine the molecular basis for the blunted response by evaluating renal Na transporter and SPAK abundance and phosphorylation in IFNg KO vs WT mice using quantitative immunoblots. At baseline, blood pressure (BP) in IFNg KO mice was similar to WT, yet abundance of NKCC2p, NCCp and SPAKp were elevated, evidence for Na transporter activation in the distal nephron. AngII infusion into WT mice raised BP 38 mmHg and increased abundance of NKCC2p, NCCp, SPAK and SPAKp and cleaved form of α ENaC. AngII infusion into IFNg KO raised BP 15 mmHg yet did not change NKCC2p, NCCp, SPAK or SPAKp; however, AngII infusion increased cleaved form of αENaC.

WT+AngII vs. WT ‐ baseline
IFNg KO vs. WT ‐ baseline
IFNg KO+AngII vs. IFNg KO

NKCC2
0.79 ± 0.03*
1.01 ± 0.09
1.46 ± 0.18

NKCC2p
4.17 ± 0.60*
6.12 ± 1.17*
1.25 ± 0.31

NCC
0.88 ± 0.03
1.28 ± 0.10
1.22 ± 0.09

NCCpS71
8.96 ± 2.53*
8.33 ± 2.55*
1.66 ± 0.40

α‐ENaC (90 kDa)
1.42 ± 0.12*
1.09 ± 0.06
1.54 ± 0.15*

α‐ENaC (20 kDa)
2.41 ± 0.12*
1.28 ± 0.1*
1.64 ± 0.25*

SPAK
1.41 ± 0.12*
1.28 ± 0.11
1.18 ± 0.10

SPAKp
1.71 ± 0.24*
1.81 ± 0.10*
0.96 ± 0.13

In summary, we postulate that IFNg KO mice have a sodium‐losing phenotype that provokes a pronounced activation of NKCC and NCC phosphorylation mediated by SPAK activation, and that the response to AngII infusion is blunted because the AngII targets are already activated. NIH RO1 DK 083785
STE20‐like kinase SPAK differentially regulates Na‐(K)‐Cl cotransporters along the distal nephron under the endocrine control of AVP
Authors: Bachmann Sebastian , Saritas Turgay , McCormick James , Ellison David , Delpire Eric , Mutig Kerim 
Published: June 2021

The Na‐K‐2Cl cotransporter (NKCC2) of the thick ascending limb (TAL) and the Na‐Cl cotransporter (NCC) of the distal convoluted tubule (DCT) are critical for renal salt handling. Activation of these transporters by vasopressin (AVP) includes their N‐terminal phosphorylation. Little is currently known about the kinases that mediate this action of AVP. Two homologous Ste20‐like kinases, SPAK and OSR1, can phosphorylate the cotransporters directly. In this process, full‐length SPAK variant (FL‐SPAK) and OSR1 interact with a truncated isoform, KS‐SPAK, which has inhibitory effects. Our study tested the hypothesis that SPAK is an essential component of the AVP stimulatory pathway.Short‐ and long‐term effects of desmopressin (dDAVP), a V2 receptor‐specific agonist, on the kinases and transporters were evaluated in wild type and SPAK‐deficient mice and in AVP‐deficient rats.SPAK variants displayed prominent regulatory changes along TAL and DCT along with activation of the cotransporters, whereas OSR1 was less involved. The KS‐ and FL‐SPAK variants were modulated by AVP for their selective interaction with NKCC2 in control of its activation, whereas the phosphorylation of NCC was essentially governed by FL‐SPAK alone.In sum, our data specify how SPAK may serve as a hallmark kinase in modulating Na+ reabsorption along the distal nephron under the endocrine control of AVP.
Characterization of CFTR High Expresser (CHE) cells of the small intestine
Authors: Jakab Robert L , Ameen Nadia A 
Published: June 2021

The CHE cells express 8‐fold higher levels of the CFTR Clchannel compared to neighboring enterocytes, and were first identified by our laboratory (Ameen et al 1995, Gastroenterology 108:1016). We used double label immunofluorescence microscopy to further study these enigmatic epithelial cells in rat. CHE cells are found in duodenum, most frequent in proximal jejunum, and absent in ileum and colon. CFTR abundance increases in CHE cells along the crypt‐villus axis. The basolateral Cl− transporter NKCC1 was detected at similar levels in CHE cells and neighboring enterocytes at steady state. Microvilli were shorter in CHE cells, with low levels of Myosin1A ‐ a villus enterocyte specific motor that retains sucrase/isomaltase (SI) in the brush border membrane (BBM). CHE cells lacked absorptive villus enterocyte BBM proteins including: NHE3, SLC26A6 (PAT1) and SI. High levels of the vATPase proton pump were observed in the apical domain of CHE cells. Levels of Syntaxin 3, NHERF1, and Na‐K‐ATPase were similar to that of neighboring enterocytes. cAMP or carbachol stimulation robustly increased apical CFTR and basolateral NKCC1 disproportionately in CHE cells relative to neighboring enterocytes. These data strongly argue for a specialized role of CHE cells in Cl−‐mediated “high‐volume” fluid secretion in the proximal small intestine.NIDDK Grants R01‐DK‐077065 (N.A.) and P30 DK‐34989 (Yale Liver Center).
Chloride channels: Role in apoptosis, cell motility and chemotherapy resistance
Authors: Hoffmann Else Kay , Jacobsen Kari S , Schwab Albrecht , Sauter Daniel , Lambert Ian H , Poulsen Kristian A 
Published: June 2021

Among the pathophysiological phenotypes defining malignant growth are cell migration and evasion of programmed cell death. The talk will discuss how Cl−channels affect these processes and how changes in the expression of Cl−channels are involved in chemotherapy resistance. We investigate the role of the TMEM16 Cl− channels in cell migration in Ehrlich Lettré Ascites (ELA) cells and find that TMEM16A and TMEM16F knock‐down affects the directional migration and the rate of cell migration, respectively. Moreover we have explored the apoptotic volume decrease (AVD) in wild type (wt) and Multidrug Resistant (MDR) Ehrlich Ascites Tumor Cells (EATC). Cisplatin (5 μM) leads to AVD and apoptosis in wt EATC but essentially not in MDR cells, and the maximal capacity of the volume activated Cl− current is concomitantly strongly repressed in MDR EATC. Application of the VRAC inhibitor NS3728 prevents cisplatin‐induced AVD in wt cells and abolishes the differences in AVD and caspase‐3 activation between wt and MDR EATC suggesting that impairment of AVD via down regulation of Cl− channels protects against apoptosis in MDR EATC1. Currently, using QPCR and western blot we compare the expression of Cl− channels in wt and MDR EATC as well as in four pancreatic cancer cell lines and a normal pancreatic cell line (HPDE).Supported by DFF, Denmark.
Role of VDAC in coronary endothelial cell dysfunction in type 1 diabetic mice
Authors: Sepassi Liliyas , Sasaki Koh , Heldak Michael , Makino Ayako 
Published: June 2021

Endothelial dysfunction is a common feature of diabetic vascular complications. Rarefaction of capillaries in the heart, as a result of coronary endothelial dysfunction, represents one of the most critical mechanisms involved in cardiac ischemia. The voltage‐dependent anion channel (VDAC) plays an important role in the regulation of mitochondrial metabolic function and mitochondria‐mediated apoptosis. The objective of this study is to examine the role of VDAC in coronary endothelial dysfunction in diabetes. Endothelial cells (ECs) were more apoptotic in the left ventricle of diabetic mice and hyperglycemia induced significant increase in mitochondrial Ca2+ concentration and VDAC protein levels in coronary ECs. The expression of VDAC‐shRNA in diabetic MCECs not only decreased the mitochondrial Ca2+ concentration, but also attenuated mitochondrial superoxide anion (O2−) production and the activity of the mitochondrial permeability transition pore opening (an indirect indicator of cell apoptosis) toward control levels. These data suggest that the increased VDAC protein expression in diabetic MCECs leads to the activation of pro‐apoptotic cascade and normalizing VDAC protein level may help to decrease endothelial cell apoptosis, increase capillary density in the heart, and subsequently decrease the incidence of cardiac ischemia in diabetes.This research was supported by grant HL115578.
On the Potential Role of Potassium Channel KCNK5 in Human T Cell Activation
Authors: Kirkegaard Signe Skyum , Hansen Anker Jon , Gammeltoft Steen , Hoffmann Else Kay 
Published: June 2021

The two‐pore domain potassium channel KCNK5 has been shown to play a role in activation of T cells from multiple sclerosis patients1. KCNK5 is also known to be important in the regulatory volume decrease (RVD) following cell swelling2. Our aim with the study is to elucidate a potential role for KCNK5 in T cell activation.We use T cells purified from human peripheral blood mononuclear cells. Real‐time PCR and Western blotting was used to investigate mRNA and protein levels, respectively of the three potassium channels Kv1.3, KCa3.1 and KCNK5 in non‐activated and CD3/CD28 activated T cells. Furthermore volume measurements using a coulter counter were used to study RVD. We find a strong up‐regulation of KCNK5 on protein and mRNA levels in activated T cells compared to the non‐activated cells. Surprisingly, despite this up‐regulation of the potent volume regulator KCNK5 activated T cells were larger and volume regulated less efficiently than nonactivated cells. The exact role for KCNK5 in activated T cells will be examined in future studies of the increase in membrane potential expected from KCNK5 up‐regulation.
New Theory of Respiratory Control and Regulation
Authors: Sun Xing‐Guo 
Published: June 2021

We recently finished ¡°Holistic Regulation of LifeCIntegrative Physiology¡± framework as a whole. The part of respiratory control and regulation is decribed as below:
The key control of singles should be considered O2, while CO2 and [H+] act as subordinates to the core integration of breathing, circulation, metabolism, and other multi‐functional system control.
The trigger to inhale during the termination of exhale is when the level of PO2 gradually decreases (PCO2 and [H+], opposite).
The trigger to exhale during the termination of inhale is when the level of PO2 gradually increases (PCO2 and [H+], opposite), creating the cycle of breathing.
Cardiovascular function is the key factor in determining a normal breathing rhythm and frequency.
Regulation mode of breathing amplitude (depth): the next breath is induced as above to achieve a fast response through peripheral chemoreceptors. The breathing rate is exaggerated by the last breath, for example, a larger breath induces a larger breath, a smaller breath induces a smaller breath, and so on.
Regulatory control the steady breathing pattern must be integration with slow response of central chemoreceptors.
Cthrc1, a Novel Hormone Involved in Regulation of Metabolism
Authors: Stohn J. Patrizia , Perreault Nicole G. , Wang Qiaozeng , Liaw Lucy , Lindner Volkhard 
Published: June 2021

We discovered Cthrc1 in a screen of balloon injured arteries. It is induced in adventitial cells of injured arteries and expressed in many developing and remodeling tissues. In this study we address the role of Cthrc1 in normal adult tissues. We generated mutant mice with a novel Cthrc1 null allele, which appeared developmentally normal. As they get older, livers from Cthrc1 null mice accumulate vast quantities of lipid, leading to extensive macrovesicular steatosis. In addition, glycogen levels and cell proliferation in skeletal muscle and liver of Cthrc1 null mice were significantly increased. However, Cthrc1 expression in the adult wild‐type mouse was found in the brain and osteocytes, but not in liver or muscle. Further investigation showed Cthrc1expression predominantly in the paraventricular and supraoptic nucleus of the hypothalamus. In pigs, Cthrc1 was detected around chromophobe cells of the anterior pituitary, in colloid‐filled follicles and the pituitary cleft. Development of a sensitive ELISA demonstrated that Cthrc1 circulates in human plasma in picogram/ml quantities. Cthrc1 is a novel circulating hormone produced by the anterior pituitary, hypothalamus and bone, and is involved in regulation of lipid storage and cellular glycogen levels.This study was supported by HL69182, P20 RR‐15555, P20RR018789/P20GM103465 and P30RR030927/P30GM103392.
Large‐strain In Vivo Lengthening Contractions Induce Mitochondrially‐mediated Apoptosis in Dysferlin‐null Muscle
Authors: Roche Joseph A , Mueller Amber L , Bloch Robert J 
Published: June 2021

Background and HypothesisMutations in the DYSF gene that encodes the protein, dysferlin, are implicated in late‐onset muscle wasting syndromes known as dysferlinopathies. We tested the hypothesis that dysferlin‐null myofibers undergo mitochondrially‐mediated cell death several hours after injurious large‐strain lengthening contractions.Methods and ResultsWe subjected the tibialis anterior muscle (TA) of dysferlin‐null A/J and control A/WySnJ mice to large‐strain injury (LSI) by repeated lengthening contractions (20 repetitions). We measured isometric torque before LSI, and at 10min, 3hr, 6hr, 12hr, 24hr, 48hr, and 72hr after LSI, and harvested TA muscles from animals at these time points. There was no significant difference in maximum torque between A/J and A/WySnJ before LSI, and at 10min and 3hr after LSI. At 6hr and beyond, A/J muscle declined in torque, whereas A/WySnJ muscle continued to recover. Immunolabeling with antibodies to cytochrome c (cyt c) and complex IV (COX IV) showed that, whereas the intermyofibrillar mitochondrial network in A/J muscle becomes condensed at 3hr after LSI, it becomes more widespread and intensely stained in A/WySnJ muscle. At 6hr after LSI, cyt c is released from mitochondria causing its labeling to become diffused in the myoplasm and non‐coincidental with the COX IV labeling in A/J muscle, but not in A/WySnJ muscle. TUNEL staining showed a sharp increase in the number of apoptotic nuclei from 72±21 nuclei/mm2 at 6hr to 247±48 nuclei/mm2 at 12hr in A/J muscle compared to a small increase in A/WySnJ muscle from 12±7 nuclei/mm2 at 6hr to 77±28 nuclei/mm2 at 12hr.ConclusionContraction‐induced injury induces mitochondrially‐mediated apoptosis in dysferlin‐null muscle.Funded by a grant to JAR from the Jain Foundation Inc.
Low‐frequency electrical stimulation prevents muscle loss in mice with chronic kidney disease (CKD) by decreasing atrogin1 and MurF‐1 expression
Authors: Hu Li , Klein Janet D , Price Russ F , Wang Xiaonan H 
Published: June 2021

HypothesisLow‐frequency electrical stimulation (LFES) in muscle attenuates muscle atrophy induced by CKD.MethodCKD was induced in 20g mice by 5/6th nephrectomy. Electrode insertion points were selected using acupunture therapy guidelines. The positive needle was inserted under the fibula head near the superficial and deep fibular nerves (site name: Yang ling qian). The negative needle was inserted lateral to the knee joint under the fibula head near the fibular nerve (site name: Ho san li). The needles were connected to an SDZ‐蕅 electronic acupuncture device delivering a constant electical pulse (20Hz, 1mA) daily for 15 minutes over 4 weeks.ResultsSoleus and EDL muscle weights from uremic mice were significantly increased by LFES (P<0.05). LFES blunted the increase in CKD‐induced muscle proteolysis and improved phosphorylation of Akt (2.3‐fold, P<0.001) and FoxO3a (2.1‐fold, P<0.01). mRNAs of proteolytic atrogin‐1 and MuRF‐1 E3 ubiquitin ligases were attenuated by LFES. LFES concomitantly improved protein synthesis (increased phosphorylation of mTOR and p70S6K) and myogenesis (increased levels of MyoD, myogenin, and eMyHC) in muscles of CKD mice.ConclusionsLEFS can prevent CKD‐induced muscle loss by a multi‐faceted mechanism affecting myogenesis, protein degradation and synthesis.Support: NIH AR060268, and the NSF of China (30971471)
Fibroblast Growth Factor 10 induces goblet cell hyperplasia independently from Notch signaling
Authors: Al Alam Denise , Sala Frederic G , Danopoulos Soula , Frey Mark R , Grikscheit Tracy , Bellusci Saverio 
Published: June 2021

During gut adaptation, fibroblast growth factor 10 (Fgf10) is highly expressed in the ileal epithelium, where its levels are normally very low during homeostasis. In the colon, FGF10 stimulates cell proliferation and survival. However, whether it regulates small intestinal growth and homeostasis is unknown. Using a mouse model of inducible Fgf10 expression, we tested the role of this growth factor in the small intestine.METHODS3‐week old R26rtTA; tet(O)Fgf10 mice and littermate controls were given doxycycline food for 10 days. Cell proliferation, epithelial lineage markers, and Notch ligand expression were quantified by immunofluorescence and qPCR.RESULTSFGF10 induction led to increased cell proliferation and greater villus height in the ileum. We observed more goblet cells, but fewer Paneth cells, in induced mutants. Interestingly, there was no change in Dll1, Dll4 and Hes1 levels with Fgf10 induction.CONCLUSIONSFgf10 induces goblet cell hyperplasia, at the expense of the Paneth cell lineage, in a Notch‐independent manner. Fibroblast growth factors may have selective trophic effects on individual intestinal cell types, which could be exploited therapeutically to improve adaptation after small bowel resection.
Integrating Geriatrics with Anatomy: An Educational Collaboration between Basic Science and Primary Care
Authors: Kleber Kara Teresa , Young Megan , Zumwalt Ann 
Published: June 2021

Adapting a model introduced at Brown University, Boston University School of Medicine (BUSM) has developed a curriculum in which geriatricians and anatomists collaborate with mutual benefit. This program is a model of a productive collaboration between anatomy and a primary care specialty that benefits both faculty and students. In an innovation unique to BUSM, anatomy is taught to geriatric physicians, nurses, and students via a Grand Rounds talk on “The Anatomy of Aging.” Feedback on this session is universally positive, with respondents reporting benefits to their medical knowledge and patient care. In an adaptation of the Brown model, geriatricians then visit the gross anatomy lab when the course is 2/3 complete. The geriatricians speak informally at each lab table about clinical questions inspired by the anatomical findings in the donor, topics related to aging and disease, and issues they face as health care providers of older adults. This practice allows students to consider the donor as a person and as a patient, rather than simply an anatomical specimen. This program is well received by the students, many of whom enter BUSM with a strong inclination towards primary care.Grant Funding Source: n/a