bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reflex effects of drinking on thermoregulatory responses in hyperthermic and hyperosmotic men.
Authors: Kamijo Yoshi‐ichiro , Okada Yoshiyuki , Okazaki Kazunobu , Ikegawa Shigeki , Ogawa Yu , Nose Hiroshi 
Published: November 2023

Oropharyngeal stimulation by drinking released dehydration‐induced suppression of cutaneous vasodilation and sweating in hyperthermic humans. However, association of skin sympathetic nervous activity (SSNA) with the mechanisms remained unknown. Recently, we have reported that SSNA involved components synchronized and non‐synchronized with cardiac cycle, the components increased with an increase in esophageal temperature (Tes) and the increase in synchronized component was suppressed by hypovolemia and head‐up tilt, but that in non‐synchronized component was not. These results suggested that the synchronized and non‐synchronized components were related with cutaneous vasodilation and sweating, respectively. We hypothesized that hyperosmolality would suppress both SSNA components in hyperthermia, and oropharyngeal stimulation by drinking would release the hyperosmotic suppressions of both components, simultaneously with releasing suppressions of cutaneous vasodilation and sweating. Fourteen young males were divided into isosmolality (Iso; N = 7) and isovolume and hyperosmolality groups (Hos; N = 7) with no treatments and taking diuretics and hypertonic saline infusion before experiment, respectively. Subjects wore water‐perfused suit and took a semi‐recumbent position while 34‐°C water was perfused into the suit. After 10‐min thermoneutral data collection; mean skin temperature (Tsk), Tes, skin blood flow (SkBF; laser‐Doppler velocimetry) and sweat rate (SR; capacitance hygrometry) on the dorsal foot, and mean arterial pressure (MAP), 47‐°C water perfused into the suit for 45 min, then subjects drank a 200‐ml water, warmed at 37 °C. Data collection was continued until 10 min after drinking. Plasma osmolality were 298 and 290 mOsm/kgH2O before the onset of passive warming in Hos and Iso, respectively. Tsk increased by ~2 °C in both groups then Tes increased by 0.4 and 0.5°C at 45min of passive warming in Iso and Hos, respectively (Group × Time; P<0.05). Increases in cutaneous vascular conductance (CVC=SkBF/MAP) and SR at a given increase in Tes tended to be lower in Hos than Iso, simultaneously with suppressed increases in both SSNA components (both P < 0.02). After drinking, both SSNA components increased in Hos (P < 0.05) and an increase in CVC was faster in Hos than Iso and that in SR was greater in Hos than Iso (Group × Time; P < 0.05), while Tsk and Tes remained unchanged before and after drinking. In summary, both SSNA components would be associated with the release of hyperosmolality‐induced suppression of cutaneous vasodilation and sweating by oropharyngeal stimulation in hyperthermic men.Support or Funding InformationThis work was supported by grants from the Ministry of Education, Culture, Sports, Science, and Technology of Japan (Grant‐in‐Aid for Young Scientists (B) to Y.K., 16790143, Grant‐in‐Aid for Scientific Research (A) to H.N., 17209007) and the Uehara Memorial Fundation in 2008 to Y.K.
IMP1 plays a protective role in LIN28B‐associated intestinal tumorigenesis by regulating ER stress and cell junction assembly
Authors: Chatterji Priya , Hamilton Kathryn , Andres Sarah , Foley Shawn , Mizuno Rei , Castells Antoni , Cuatrecasas Miriam , Simon Lauren , Gregory Brian , Madison Blair , Rustgi Anil 
Published: November 2023

IntroductionRNA binding proteins and miRNAs have emerged as crucial regulators of intestinal homeostasis by controlling the stability and translation of target mRNAs. LIN28B, an mRNA binding protein, plays a critical role in regulating growth and proliferation in the intestinal epithelium. Previous work in our lab revealed that LIN28B promotes growth and tumorigenesis of the intestinal epithelium via suppression of mature let‐7 miRNAs (Genes and Dev., 2013). LIN28B suppression of let‐7 promotes upregulation of let‐7 targets, including IMP1 (Insulin‐like growth factor II mRNA‐binding protein‐1). Previous studies from our lab have shown that transgenic mice expressing LIN28B from the mouse Vil1 promoter (Vil‐Lin28b mice) have an increase in IMP1 protein levels that is increased further with conditional knockout of let‐7. Mechanistically, Let‐7 isoforms have been known to physically and functionally interact with IMP1; however, the specific role of IMP1 in Lin28b‐let 7‐mediated tumorigenesis remains unknown.MethodsWe evaluated LIN28B and IMP1 expression and localization in colorectal cancer (CRC) patient samples using tissue microarrays with clinical outcomes. We used intestinal epithelial cell lines with LIN28B overexpression and CRISPR‐Cas9 mediated knockout of IMP1 to study the functional consequences on migration, invasion and proliferation. In parallel, we used RNA sequencing to understand the role of IMP1 deletion in LIN28B over‐expressing cell lines. Additionally, we used mice with intestinal epithelium specific LIN28B overexpression combined with IMP1 knockout to evaluate effect of IMP1 loss on tumor initiation and progression in an aging model as well as through AOM‐DSS induced tumorigenesis.ResultsLIN28B expression correlates positively with expression of IMP1 in CRC. Individually, LIN28B and IMP1 expression associated significantly with worse prognosis in stage II colon cancer that worsens when both were co‐expressed. Knockout of IMP1 in LIN28B overexpressing cells decreased migration of CRC cell lines and altered tumorigenesis in vivo. RNA‐seq revealed a potential role for IMP1 in ER stress and cell junction assembly proteins in the context of LIN28B overexpression.ConclusionsThese data suggest a requirement for IMP1 in LIN28B‐mediated colorectal tumor progression, potentially via ER stress modulation, and support an emerging paradigm for a critical and cooperative role of RNA‐binding proteins in intestinal homeostasis and cancer.Support or Funding InformationNIH R01DK056645 (AKR), NIH U01DK085551 (AKR), NIH K01DK100485 (KEH),NIH F32DK107052‐01 (SFA), NIH T32CA1152999 (SFA)
The Effect of a Western Diet on Hepatic Autophagy in Age Accelerated SAMP8 Mice
Authors: Harris Matthew P , Schaller Megan L , Umbaugh David , Sandoval Karin , Witt Ken A , Wooten Joshua S 
Published: November 2023

Non‐alcoholic steatohepatitis (NASH) is characterized as a dysregulation of hepatic lipid metabolism and a chronic inflammatory state. It is hypothesized the link between lipid dysregulation and inflammation may be due in part to defective hepatic autophagy and reduced mitochondrial capacity to oxidize fatty acids. It remains to be determined; however, the effects of a Western diet on hepatic autophagy and mitochondrial function during aging.PURPOSEThe purpose of this study was to determine the effect of a high‐fat high‐fructose diet (HFF) on markers of hepatic autophagy and mitochondrial function in an age‐accelerated mouse model.METHODSTwenty‐week old, male and female, SAMP8 mice (n=49) were randomly assigned, matching for gender, to either a standard chow (SC) or HFF (45% fat, 24% fructose) diet for 32 weeks. Liver tissue was analyzed for mRNA expression of autophagic (BNIP3, Beclin 1, p62, and Atg7) and mitochondrial (PGC‐1α and COX‐IV) genes. Differences between gender and dietary groups were identified by a 2 × 2 ANOVA and statistical significance was set at p<0.05.RESULTSFollowing 32 weeks of feeding, male mice fed the HFF diet were significantly heavier than male mice in the SC group (31.64 vs 26.45; p=0.001); however, no difference was observed between diet groups for female mice. The HFF diet resulted in higher autophagic activity as observed by Beclin 1 (+36%; p=0.001) and BNIP3 (+40%; P=0.003) expression. Despite the higher autophagic activity, p62 (+31%; p<0.001) was higher in the HFF compared to the SC group, suggesting impaired autophagic flux. In addition, mitochondrial COX‐IV expression was elevated (+43%; P<0.001) in the HFF group compared to the SC group suggesting increased β‐oxidation. Overall, the expression of all autophagic and mitochondrial markers were higher in males compared to females; however both male and female mice responded similarly to the HFF diet.CONCLUSIONDespite the higher expression of autophagic and mitochondrial genes, elevated expression of p62 suggests an impaired autophagic flux in age‐accelerated mice following a Western diet.
The phenotype and wound healing property of IL‐4‐treated human macrophages is not affected by co‐treatment with antigen from the tapeworm, Hymenolepis diminuta
Authors: Jayme Timothy Santiago , Luis Jose , Wang Arthur , Thomson Emma T. , Beck Paul , McKay Derek 
Published: November 2023

BackgroundInfection with parasitic helminths can reduce inflammation in animal models of colitis. A component of this anti‐inflammatory effect may be induction of alternatively‐activated IL‐4 driven anti‐inflammatory/pro‐resolution macrophages (M(IL4)) that have been implicated in wound repair. Infection with helminth parasites or exposure to worm extracts may elicit unique macrophage phenotypes. We hypothesized that macrophages co‐treated with IL‐4 and a crude extract Hymenolepis diminuta (HdE), would have an enhanced ability to promote repair in wounded epithelial monolayers.AimTo assess the impact of HdE on the development of human and murine M(IL4)s using canonical markers and assess the ability of these cells to promote epithelial wound repair.MethodsHuman (blood‐derived) and murine (bone marrow‐derived) macrophages were exposed to IL‐4 (10 ng/ml; 48h), HdE (100 mg/ml; 48h), IL4+HdE, or left unstimulated (controls). Expression of M(IL4) markers were assessed by qPCR, immunoblotting or ELISA (human: CD206, CCL18, CD14; murine: arginase‐1, Ym1). Confluent Caco2 epithelial cell monolayers were wounded with a razor blade and treated with supernatants from the different human macrophage sub‐types populations; protein denatured (trypsin‐treated + boiling) were also used. The total area of epithelial migration was measured (in mm2) 24h later. TGFb levels in the macrophage supernatants were measured by ELISA.ResultsThe development of human M(IL4)s was not affected by HdE co‐treatment as assessed by any of the markers examined, whereas HdE did reduce arginase‐1 and Ym1 in murine M(IL4)s (n=4–6). Supernatants from M(IL4)s increased epithelial migration by 36% ± 14% (n=8, p<0.05) compared to baseline, and this was not affected by HdE co‐treatment of the macrophages. Protein denaturing ablated the ability of M(IL4) supernatant to enhance epithelial wound repair (n=6). TGFb levels were increased in M(IL4) supernatants (353 ± 78*) compared to those from non‐stimulated macrophages (204 ± 71 pg/ml) (n=11; *p<0.05 (paired t test)).ConclusionHdE has negligible effects on the induction of a human M(IL4) and does not inhibit its ability to promote epithelial wound repair, that could be TGFb dependent. Thus, (1) M(IL4)s elicited in humans following infection with helminths will not be adversely affected by the release of worm antigen, and (2) if an anti‐colitic effect of systemic delivery of helminth antigens to humans results in mobilization of an IL‐4‐type alternatively activated macrophage, this would be an indirect effect of the worm antigen.Support or Funding InformationSupported by Crohn's Colitis Canada grant to DMM and an NSERC CREATE Host‐Parasite Interactions scholarship to Timothy Jayme
Colonic inflammation and cancer are driven by elevated D‐2‐hydroxyglutarate levels in an EglN1‐dependent mechanism
Authors: Theiss Arianne L. , Han Jie , Turner Kevin O. , Genta Robert M. , Sweetman Lawrence 
Published: November 2023

Emerging evidence suggests a crucial role for altered expression of enzymes with functions in cellular metabolism in the pathogenesis of inflammation and cancer. But the detailed molecular mechanisms that link these alterations to carcinogenesis remain elusive. Here, we identify a novel role for altered metabolism of D‐2‐hydroxyglutarate (D2HG) in colitis and colitis‐associated colon cancer. We found that the levels of D2HG were elevated in the urine of mice during dextran sodium sulfate (DSS)‐induced colitis. In a mouse model of colitis‐associated cancer, intraperitoneal injection of D2HG resulted in delayed recovery from colitis and severe tumorigenesis. The colonic expression of D‐2‐hydroxyglutarate dehydrogenase (D2HGDH), an enzyme that eliminates D2HG, was decreased during DSS colitis and human ulcerative colitis (UC) but unaltered in mouse or UC tumors. Mechanistically, we demonstrate that elevated expression of Egg‐laying defective Nine 1 (EglN1) inhibited hypoxia inducible factor (Hif)‐1a, which in turn attenuated D2HGDH transcription, thereby resulting in elevated D2HG. Furthermore, pharmacological inhibition of EglN1 ameliorated colitis‐associated cancer in mice. Thus, we have identified a novel regulatory mechanism where D2HG promotes colonic inflammation and carcinogenesis, which may provide functional therapeutic targets to inhibit the progression from colitis to cancer.Support or Funding InformationCancer Prevention & Research Institute of Texas grant RP150638 (A.L.T) and Charles A. Sammons Cancer Center, Baylor University Medical Center grant (A.L.T).
Immunohistochemical Identification of Purinergic Neurons in the Enteric Nervous System
Authors: Perez‐Medina Alberto L , Galligan James J. 
Published: November 2023

Propulsive gastrointestinal (GI) motility patterns depend on coordinated contraction and relaxation of GI smooth muscles. The enteric nervous system (ENS) controls GI motility. Currently, it is accepted that smooth muscle relaxation is mainly mediated by the co‐release of ATP and nitric oxide (NO) from one class of inhibitory motor neuron (IMN). ATP and NO mediate fast and slow inhibitory junction potentials, respectively. Neuronal ATP and NO release depend on activation of voltage‐gated calcium channels (VGCC) and different VGCC may drive ATP and NO release independently. Functional data also suggest that descending interneurons communicate with other interneurons and IMNs via ATP release. However, direct identification of purinergic nerves in the ENS is lacking. Our study aim was to directly identify purinergic nerves in the ENS using an antibody against the vesicular nucleotide transporter (VNUT, SLC17A9), a purinergic nerve marker to distinguish the purinergic and non‐purinergic neurons in mice and guinea pig colon and ileal myenteric plexus. We used immunohistochemical methods to localize nitric oxide synthase (NOS), VNUT, choline acetyl transferase (ChAT) and the a1E subunit of the R‐type Ca2+ channels. . In addition, longitudinal muscle myenteric plexus (LMMP) preps were placed in tissue culture with colchicine for 48 h to facilitate staining of purinergic and non‐purinergic nerve cell bodies. Our results show VNUT+/NOS‐‐, NOS+/VNUT‐, ChAT+/VNUT‐, and ChAT‐/VNUT+ nerve fibers supplying the muscle layers. Moreover, multiple populations of cell bodies were identified (VNUT+ neurons, NOS+ neurons, and NOS‐/VNUT+ neurons), NOS+/VNUT+ neurons being the smallest population observed. In addition, VNUT and ChAT did not co‐localize in myenteric neurons. Finally NOS and the a1E subunit localize in the same axon bundles, but not in the same axons, that innervate the smooth muscle. These results suggest that there may be two types of inhibitory motorneuron supplying the muscle layers in the gut (purinergic and nitrergic). There may also be two types of excitatory interneurons: cholinergic and puringergic. Further studies of neuromuscular and synaptic transmission are required to establish the function of the puringeric, nitrergic and cholinergic neurons.(Supported by 1R01DK094932)Support or Funding InformationSupported by 1R01DK094932
Epithelial Interleukin‐15 Functions as a Chemoattractant for γΔ IEL Migration
Authors: Edelblum Karen L , Ethridge Alexander D , Hu Madeleine 
Published: November 2023

Positioned between intestinal epithelial cells in the lateral intercellular space, intraepithelial lymphocytes (IEL) expressing the γΔ T cell receptor exhibit a surveillance‐like migratory behavior, which is required to limit microbial invasion. Epithelial interleukin (IL)‐15 is critical for the development, proliferation and survival of γΔ IELs; however, the role of IL‐15 in γΔ IEL migration remains unclear. Transpresentation of membrane bound IL‐15 requires cell‐cell contact between activating and responder cells, thus based on the direct interactions between IELs and epithelial cells we tested the hypothesis that IL‐15 exposure promotes γΔ IEL migration into the lateral intercellular space. To this end, in vitro migration assays were performed by co‐culturing γΔ IELs with Caco2 epithelial cells in the presence of recombinant IL‐15. We found that IL‐15 induced γΔ IEL migration in a dose‐dependent manner (P<0.001). In contrast, the addition of IL‐15 neutralizing antibody reduced basal migration by nearly 25% (P<0.05), indicating that basal epithelial IL‐15 expression contributes to γΔ IEL migration in vitro. Since IL‐15 has been reported to function as a NK cell chemoattractant, we performed 3D chemotaxis assays in which sorted GFP+ γΔ IELs were embedded in Matrigel, exposed to an IL‐15 diffusion gradient and timelapse microscopy was performed. Over the course of 6 hours, IL‐15 significantly enhanced both the track displacement and velocity of γΔ IEL migration (P<0.0001), demonstrating that IL‐15 alone is sufficient to promote γΔ IEL motility. Lastly, to assess the requirement for epithelial IL‐15 in γΔ IEL migration into the lateral intercellular space, γΔ IELs were co‐cultured with enteroids derived from the jejunum of wildtype mice or those overexpressing murine IL‐15 in the intestinal epithelium (vil‐IL‐15). Morphometric analysis of γΔ IEL number and location within the co‐cultures showed that vil‐IL‐15 expression increased the number of γΔ IELs associated with enteroids by 38±0.2% (P<0.05) and migration into the lateral intercellular space by 17±7.1% (P<0.05). Taken together, these data indicate that epithelial IL‐15 expression functions as a γΔ T chemoattractant and demonstrates a novel role for IL‐15 in maintaining basal γΔ IEL surveillance of the villous epithelium.Support or Funding InformationNIH, RBHS Chancellor Scholar Award
RGS10 Mediates Changes in Gut Permeability and Inflammation After an Intestinal Inflammatory Challenge
Authors: Khosravian Kiana , Houser Madelyn , Tansey Malu 
Published: November 2023

Parkinson's disease (PD) pathology is marked by degeneration of dopamine neurons and the accumulation of the protein alpha‐synuclein in Lewy bodies in the Substantia Nigra pars Compacta (SNPC). A lesser known aspect of PD pathology is chronic intestinal inflammation which may promote the progression of the disease by dysregulating alpha‐synuclein in the gut. Regulator of G‐protein signaling 10 (RGS10) is a GTPase‐activating protein that is expressed in intestinal immune cells and acts as an anti‐inflammatory regulator by inhibiting NFkB. Previous studies have also shown that RGS10 knock‐out mice developed dopamine neuron loss in the SNPC after systemic lipopolysaccharide exposure. We have also found that mice deficient in RGS10 have higher levels of NFkB in the intestine, significantly shorter intestine lengths, increased fecal water content, and changes in tight junction protein expression. We predicted that reductions in RGS10 expression would increase inflammation and permeability in the intestine to a greater extent in the context of a chemical inflammatory challenge, modeling, perhaps, the contribution of pronounced intestinal inflammation to Parkinsonian neuropathology. To evaluate this, we subjected RGS10 knockout, heterozygous, and wild‐type mice to a dextran sodium sulfate (DSS) colitis model. We took baseline measurements of weight as well as peripheral blood immune cell populations by flow cytometry. For a total of 14 days, mice were monitored for weight loss and bloody stool. At the end of the experiment, a FITC‐dextran gut permeability assay was performed. The mice were then sacrificed, and small intestine and colon length were measured, along with cecum weight. We collected blood, brain, and gut tissue for flow cytometry, qPCR, and Western blots. We found that RGS10 knockout mice have significant changes in immune cell population. We will compare the effect of RGS10 deficiency on levels of intestinal inflammation at baseline and after DSS. Our work will demonstrate that RGS10 deficiency leads to changes in intestinal structure and immunity, which can increase the risk for Parkinsonian‐like pathology in knockout mice.Support or Funding InformationAcknowledgments: This work was supported by NSF Graduate Research Fellowship DGE‐1444932 and the American Physiological Society's Undergraduate Summer Research Fellowship. A special thank you to the Tansey Lab and the Emory University Department of Physiology.
Inhibition of PTK6 Improves Intestinal Barrier Function and Claudin‐3 Expression in an Experimental Mouse Model for Ulcerative Colitis
Authors: Haines Ricci J , Eitnier Rebecca A , Zhang Shimin , Wang Fang , Wu Mack H 
Published: November 2023

Ulcerative colitis (UC) is a debilitating disease characterized by chronic inflammation in the gut. It is thought that increased intestinal permeability is an initial physiological mechanism that gives rise to the persistent state of inflammation. In fact, it has been demonstrated that targeting epithelial cells in a manner that increases intestinal barrier function provides patients with significant relief and fewer subsequent flare‐ups. Since protein tyrosine kinase 6 has recently been shown to play a critical role in intestinal epithelial barrier function, and PTK6 is most highly expressed in intestinal epithelial cells, we hypothesized that targeting PTK6 would improve intestinal barrier function as well as reduce clinical signs of UC. Gut mucosal barrier function was evaluated by measuring gut lumen‐to‐blood transport of a fluorescent tracer using a mouse model for experimental UC in both wild type (WT) and transgenic null mice for PTK6 expression. We found that genetic ablation of PTK6 improved gut barrier function by approximately two‐fold in the animal with experimentally induced UC. Similarly, we observed three‐fold improvement of gut barrier function in the UC mice treated with a pharmacological PTK6 inhibitor. In addition, H&E staining of colonic tissues in UC mice showed enhanced crypt structure in mice with genetic interruption of PTK6 or those treated with PTK6 inhibitor. Western blot analysis of colonic tissues showed UC mice had elevated levels of active PTK6, decreased detection of the tight junction protein claudin‐3, increased detection of pY925 focal adhesion kinase (FAK), and elevated expression of matrix metalloproteinase 9 (MMP9). Fecal supernatants from UC WT mice showed enhanced detection of cleaved E‐cadherin consistent with the size generated by MMP9 cleavage. Since PTK6 is known to phosphorylate FAK at Y925, and this phosphorylation event is important for MMP9 expression, we explored whether PTK6 interruption could enhance claudin‐3 expression and reduce the level of FAK pY925, active MMP9 and cleaved E‐cadherin in fecal supernatants. Indeed, colonic lysates from UC PTK6 null mice showed significant reductions of pY925 FAK, active MMP9 and E‐cadherin cleavage when compared to the lysates obtained from WT UC mice. Immunostaining of histological samples also showed improved tight junction organization and claudin‐3 localization at epithelial tight junctions. Taken together, these results suggest that PTK6 plays a critical role in mediating gut mucosal barrier injury in UC and may potentially regulate FAK‐dependent MMP9 activity.Support or Funding InformationIBX000799, NIH HL‐120954