bluuebunny/crossref_metadata_2025_split huggingface dataset:
Early Life Adversity in Rodent and Porcine Models Induces Enteric Cholinergic System Upregulation and Mast Cell Hyperplasia
Authors: Pohl Calvin Seneca , Fried David , Gulbransen Brian , Moeser Adam 
Published: November 2023

Early life adversity (ELA) is a major risk factor for development of functional gastrointestinal (GI) disorders (FGID's) later in life. Disturbances in enteric nervous system function play a central role in stress‐related GI disease associated with ELA, but the alterations in ENS function and phenotype are poorly understood. We addressed this issue by characterizing the changes in intestinal secretomotor neuron function and motility induced by ELA in the murine neonatal maternal separation (NMS) model and the porcine early weaning stress (EWS) model. Compared with normal‐handed (NH) control mice, adult, C57BL/6 mice previously exposed to NMS exhibited alterations in colonic motility characterize by increased strength (130%), duration (130%) and frequency (200%) of migrating motor complexes, (p<0.001). Using a combination of Ussing Chambers and electrical field stimulation, we found that NMS mice exhibited heightened ileal and colonic secretomotor neuron activity measured as delta short circuit current (Isc) (2 fold increase relative to NH controls, p<0.05). Quantitative PCR and Western blotting showed an upregulated (by 1.3 fold) expression of choline acetyltransferase (CHAT) and vesicular choline acetyltransferase (VACHT), both involved in acetylcholine synthesis and transport (p<0.05). Choline transporter 1 (CHT1) and Acetylcholinesterase (ACHE) were unchanged in NMS mice. Mast cell tryptase was upregulated (by 1.6 fold) in colonic tissue of NMS mice compared to NH controls (p<0.05). Similarly, juvenile and adult pigs that were previously subjected to EWS, exhibited 2–3 fold heightened ileal cholinergic‐mediated Isc responses (p<0.05) that was more pronounced in female pigs compared with males. Coinciding with elevated cholinergic activity in EWS pigs were increased numbers of intestinal mast cells which were found in close‐proximity to submucosal and myenteric ganglia. Further, EWS pigs exhibited elevated mast cell mediator release compared to non‐stressed controls. Together, these studies demonstrate that ELA induces a persistent upregulation of proteins involved in acetylcholine synthesis and trafficking, which coincided with heightened motility, secretomotor function, and mast cell hyperplasia. The combination of heightened cholinergic signaling and mast cell hyperplasia and hyperactivity may contribute to the mechanism which links ELA to adult FGIDs. Future studies will investigate possible cholinergic nerve, mast cell nerve circuits that may develop and induce intestinal dysfunction and increased GI disease risk following ELA.Support or Funding InformationMichigan State University Matilda Wilson Endowment; NICHD R01 HD072968 AJM; NIDDK R03 DK097462 AJM; NIDDK K08 DK084313 AJM
Genetic deletion of mu opioid receptors from Kölliker‐Fuse neurons reduces morphine‐induced respiratory depression
Authors: Levitt Erica S , Bissonnette John M , Kieffer Brigitte 
Published: November 2023

Activation of mu opioid receptors in the pontine Kölliker‐Fuse (KF) causes a reduction in respiratory rate in anesthetized rats. We have previously shown that mu opioid agonists hyperpolarize a population of KF neurons (Levitt et al., J Physiol, 2015). The goal of these experiments was to determine the contribution of the opioid‐sensitive KF neurons to the reduction in respiratory rate caused by systemic administration of the opioid agonist morphine. Targeted deletion of mu opioid receptors was accomplished by viral expression of Cre recombinase in the KF of mice with floxed mu opioid receptors. Experiments were performed 4– 6 weeks later. In whole‐cell recordings from brain slices, infected KF neurons were no longer hyperpolarized by opioid agonist, confirming deletion of mu opioid receptors. Head‐out plethysmography was used to measure respiratory rate. Morphine (10 mg/kg, ip) caused a significantly smaller reduction in respiratory rate in mice with bilateral deletion of mu opioid receptors from KF, compared to uninjected or GFP injected controls. The time‐course for the effect of morphine was also delayed in mice lacking mu receptors in KF neurons. Thus, opioid‐sensitive KF neurons contribute to, but are not entirely responsible for, systemic morphine‐induced respiratory depression.Support or Funding InformationNIH K99/R00 DA038069
Effects of the 5‐HT1A Agonist 8‐OH DPAT on Basal Inspiratory Motor Output and the Acute Hypercapnic Ventilatory Response in Urethane‐anesthetized Spontaneously Breathing Adult Male C57BL/6 Mice
Authors: Srichawla Bahadar , Solomon Irene C 
Published: November 2023

Numerous studies have shown that activation of serotonin (5‐HT) receptors can exert marked effects on basal inspiratory motor activities as well as chemical control of breathing. While many of these studies have focused on the role of 5‐HT2A receptors in neural control of breathing, the roles of other 5‐HT receptors are only beginning to be appreciated. Here, we studied the effects of systemic application of the 5‐HT1A receptor agonist 8‐hydroxy‐2‐(di‐npropylamino) tetralin (8‐OH DPAT) on basal inspiratory motor output and the acute hypercapnic ventilatory response (HCVR) in spontaneously breathing urethane‐anesthetized adult male C57BL/6 mice. For these experiments, EMG activities from diaphragm (EMGDia) and genioglossus (EMGGG) muscles were recorded under baseline conditions (40% O2 in a balance of N2), during the acute HCVR (7% CO2/40% O2/balance of N2 for 5 min), and during recovery both before and 20–30 min after subcutaneous administration of 8‐OH DPAT (0.3 mg/kg). A similar recording protocol was used in control experiments in which mice received saline injections. We found that before administration of 8‐OH DPAT or saline, the HCVR was characterized by an ~10% increase in breathing frequency with variable effects on amplitude. Administration of 8‐OH DPAT produced an initial robust increase in inspiratory burst frequency (by 60.1±32.2%; P=0.035), which declined to a steady‐state level that was still elevated over the initial CO2 recovery level (by 31.1±7.4%; P=0.007); no persistent changes in breathing frequency were observed following saline administration. Following administration of 8‐OH DPAT, the HCVR frequency increase was attenuated or abolished. In contrast, saline‐treated mice exhibited a similar or enhanced HCVR frequency response. These findings indicate that 8‐OH DPAT‐induced activation of 5‐HT1A receptors not only enhances basal inspiratory burst frequency but also significantly alters the acute HCVR.Support or Funding InformationThomas Hartman Center for Parkinson's Disease Research at Stony Brook University
Cholinergic modulation of pedunculopontine tegmental nucleus in respiratory control
Authors: Lima Janayna D , Sobrinho Cleyton R , Santos Leonardo K , Takakura Ana C , Mulkey Daniel K , Moreira Thiago S 
Published: November 2023

The pedunculopontine tegmental nucleus (PPTn) has been shown to have important functions relevant to the regulation of behavioral states and various motor control systems, including breathing control. The PPTn is considered an important nucleus in the mesopontine region with considerably cholinergic input to the ventral respiratory column. In addition, recent studies indicate that cholinergic innervation of the ventral respiratory column may play an important role in modulation of breathing. Here, we investigated a cholinergic projection from the PPTn to the retrotrapezoid nucleus (RTN) and if the stimulation of cholinergic neurons in the PPTn elicit changes in the respiratory pattern in conscious rats. Male Wistar rats (280–350g, N = 3–7/group) with unilateral stainless steel cannula implanted into the PPTn were used. Respiratory parameters (tidal volume (VT), respiratory frequency (fR) and ventilation (VE)) were analyzed by whole body pletismography. Retrograde tracer FluorGold (FG‐2%) injected into the RTN region showed a light direct cholinergic projection from PPTn to RTN. In unrestrained awake rats, unilateral injection of the cholinergic muscarinic agonist carbachol (10 mM − 100 nL) in the PPTn decreased fR (60 ± 8, vs. saline: 102 ± 8 breaths/min) and VE (315 ± 105, vs. saline: 604 ± 114 ml/kg/min), without changing VT. We conclude that cholinergic stimulation of PPTn has a significant impact on the breathing activity. Our data suggest that PPTn may influence breathing through a direct pathway from the mesopontine region to the RTN.Support or Funding InformationFAPESP, CNPq, CAPES‐PROEX
REDUCTION OF PERIAQUEDUCTAL GRAY PROJECTING NEURONS TO THE RETROTRAPEZOID NUCLEUS IN A 6‐OHDA MODEL OF PARKINSON'S DISEASE
Authors: Lima Juliana C , Moreira Thiago C , Takakura Ana C 
Published: November 2023

Parkinson's disease (PD) is characterized by a reduction in the number of dopaminergic neurons of the substantia nigra (SN) accompanied by motor and non‐motor deficiencies such as respiratory failure. Among the non‐motor symptoms, the disease has respiratory complications, and the one that is the leading cause of death in PD is obstructive sleep apnea. Our laboratory suggested an impairment in brain regions crucial for breathing automaticity such as the retrotrapezoid nucleus (RTN) and a decrease in respiratory rate in a model of PD. In addition, we also showed no direct projections from SN to RTN, but we identified a connection that bypass the periaqueductal gray (PAG), a region with important modulatory role in respiratory activity. Therefore, our aim was to investigate whether there is a reduction in the number of neurons in PAG and whether the neurons in the PAG that project to RTN are reduced in the animal's model of PD. male Wistar rats (250 – 300 g; N = 3–5/group, CEUA:99/22/03) with vehicle or 6‐hydroxydopamine (6‐OHDA) injection in the Caudate and Putamen (CPu) region were used. After 30 days, one group of animals received the injection of the retrograde tracer Fluorogold (2%) in the RTN. Fourty days after 6‐OHDA or vehicle injection, all animals were submitted to hypercapnia for 3 hours and perfused for immunohistochemistry to evaluate the neuronal marker (NeuN‐ir), and the presence of fos in PAG neurons that project to RTN. In 6‐OHDA‐lesioned rats, there is a reduction in the density of NeuN‐ir in the dorsomedial (10 ± 3 vs. vehicle: 23 ± 1%), dorsolateral (15 ± 6 vs. vehicle: 38 ± 2%) and the ventrolateral (14 ± 5, vs. vehicle: 30 ± 1%) regions of the PAG and a reduction in the number of TH‐ir varicosities in the PAG (778 ± 135 vs. vehicle: 1338 ± 133). Moreover, the number of neurons in PAG activated by hypercapnia that project to RTN is reduced in the dorsolateral (3 ± 1 vs. vehicle: 21 ± 12) and ventrolateral (4 ± 1, vs. vehicle: 116 ± 8) regions in 6‐OHDA‐lesioned rats. We conclude that there is a commitment of the pathway between PAG and RTN in the animal's model of PD.Support or Funding InformationFAPESP, CNPQ, CAPES
Repetitive Acute Intermittent Hypoxia Affects Lesion Volume After Cervical Spinal Injury
Authors: Santiago‐Moreno Juan Gabriel , Satriotomo Irawan , Dougherty Brendan J , Springborn Sarah , Kopp Elizabeth , Sullivan Lydia , Mitchell Gordon S 
Published: November 2023

After spinal cord injury (SCI), lesion volume increases progressively as axons withdraw from the site of injury. Strategies to promote growth through the injured spinal cord will require treatments to minimize or reverse such spinal degeneration. Repetitive exposure to acute intermittent hypoxia (rAIH) has emerged as a promising new treatment to restore motor function after chronic SCI. rAIH elicits spinalplasticity by increasing growth/trophic factor expression, including BDNF and VEGF; both trophic factors also promote neuroprotection and neural progenitor cell proliferation, differentiation and survival. To explore the potential for rAIH to preserve/restore spinal integrity after injury, double‐blinded studies were initiated on rats with cervical spinal hemisections (a single slice injury); two months post‐injury, the rats began six months exposures to rAIH (10, 5 min episodes of 10.5% O2 per day; 5 min normoxic intervals; 3 × per week) or sham normoxia (designated as groups A & C). Rats were sacrificed two months after rAIH had ended. Since our analyses are still ongoing, the blind has not been broken. Preliminary analyses demonstrate significant differences in lesion size and scar tissue volume between groups (A: 31±3% versus C: 49±6%; p = 0.02, n = 5). Astroglia penetrate the lesioned area and more proliferating neuronal somata surround injured area in group A versus C. We await analysis of additional animals and breaking of the blind to determine if rAIH exerts beneficial or deleterious effects on injury volume. Regardless of rAIH effects, our results will be of major interest as we attempt to develop this promising new treatment for chronic spinal injuries, an injury for which there is currently no effective therapy.Support or Funding InformationSupported by NIH HL69064, DoD, Craig H. Neilsen Foundation, and McKnight Brain Institute.
Sex differences in hepatic MCT1 and CD147 expression
Authors: Cao Jieyun , Ng Michael , Felmlee Melanie A 
Published: November 2023

PurposeMonocarboxylate transporter 1 (MCT) belongs to the solute carrier super family, and transports monocarboxylates such as ketone bodies, lactate and pyruvate, as well as drugs such as gamma‐hydroxybutyric acid. CD147 interacts with MCT1 as an ancillary protein for trafficking to the plasma membrane. Previously, it has been shown that MCT expression changes under different sex hormone conditions in skeletal muscle and Sertoli cells. However, it is unknown if MCT1 or CD147 demonstrates sex differences in the liver where MCT1 play an important role in drug disposition. The purpose of this study is to evaluate hepatic MCT1 and CD147 mRNA and protein expression in males, over the estrus cycle in female rats and in the absence of female sex hormones.MethodLiver samples were harvested from 6 groups of rats (N = 3 – 5 per group): females at the four stages of the estrus cycle (proestrus, estrus, metestrus, diestrus), ovariectomized (OVX) females and male Sprague‐Dawley rats. Estrus cycle stages of females were classified by vaginal lavage smear. Hepatic mRNA expression of MCT1 and CD147 were analyzed by qPCR. Whole cell and membrane protein expression of MCT1 and CD147 were evaluated by western blot.ResultsMCT1 mRNA expression was significantly lower (0.4 and 0.3 fold respectively) in proestrus and metestrus compared to control (male rats). OVX and male rats showed similar MCT1 mRNA and whole cell protein expression. Membrane MCT1 expression in proestrus, metestrus, and diestrus groups was significantly lower (21% – 42%) compared to OVX rats. MCT1 total and membrane protein expression were positively correlated (r = 0.69). Hepatic membrane bound ancillary protein CD147 in males was significantly higher (2.3 – 3 times) than other groups whereas mRNA and whole protein expression did not show any difference.ConclusionMCT1 mRNA expression is lower in the presence of female sex hormones indicating they play a role in reducing MCT1 mRNA expression in liver. Ovariectomy increased membrane MCT1 expression compared to female rats indicating female hormones negatively regulate MCT1 membrane expression. Significant sex differences were observed in membrane CD147 expression, whereas there was no difference in whole cell protein and mRNA levels demonstrating that androgens are involved in regulating CD147 membrane localization. This study reveals that hepatic MCT1 and CD147 expression and localization were regulated by sex hormones. Sex differences in hepatic MCT1 expression may lead to altered drug disposition of its substrates, so it is critical to understand the role of sex hormones and MCT1 regulation.
Dissecting the role of PLD2 signaling pathways in endothelial barrier recovery.
Authors: Shaaya Mark , Fu Panfeng , Vogel Stephen , Karginov Andrei , Natarajan Viswanathan 
Published: November 2023

RationaleAcute lung injury (ALI) is a life‐threatening form of hypoxemic respiratory failure, characterized by inflammation, damage to the alveolar‐capillary barrier, and accumulation of fluid in the lung resulting in pulmonary edema. In order for the pulmonary barrier to recover, endothelial cells at the injury site must migrate to reseal the inter‐endothelial gaps formed in the injury phase. Phospholipase D (PLD)‐mediated generation of phosphatidic acid (PA) plays an important role in cell migration; therefore, we hypothesize that PLD/PA signaling contributes to the pulmonary endothelial barrier recovery process in ALI resolution.MethodsHuman Lung Microvascular Endothelial Cells (HLMVECs) permeability to thrombin or edemagenic agents was determined by Electric Cell‐substrate Impedance Sensing system, and trans‐well permeability assay. Western blot was performed to assess changes in FAK, c‐Src and Paxillin phosphorylation in response to Thrombin. Epifluorescence imaging was performed and time‐lapse movies were taken for 3 h after thrombin stimulation at 2‐min time intervals in the absence or presence of PLD1 or PLD2 inhibitors. Metamorph and MATLAB softwares were used to quantify cell spreading, protrusive activity, and focal adhesions (FA) count. To analyze FAs spatiotemporal dynamics, we used total internal reflection fluorescence (TIRF) was used. The ex‐vivo role of PLD2 on PAR‐1 peptide‐mediated lung inflammation and injury was evaluated in wild type (WT) and PLD2 knockout (KO) mice. Lungs were isolated from WT or PLD2 KO mice under isoflurane anesthesia, ventilated (PIP 12 cm H2O), and perfused (2 ml/min at 37°C) for determinations of lung liquid permeability (microvessel filtration coefficient, Kfc).ResultsInhibition of PLD2 catalytic activity in HLMVECs significantly increased thrombin‐induced endothelial permeability. Inhibiting PLD2 activity had no effect on thrombin‐induced protrusive activity; however, cells failed to spread and recover after 3‐h of thrombin treatment. This suggests that PLD2 is not essential for cells to send out protrusions, but is required for their adhesion to the matrix. PLD1 inhibition did not alter cell‐spreading dynamics. Further, inhibition of PLD2 activity destabilized focal adhesions resulting in less cell spreading. Genetic deletion of PLD2 in mice increased pulmonary leak in response to PAR‐1 agonist compared to WT mice. Also, PLD2 knockout mice had more lung injury in an intratracheal LPS‐induced ALI model.ConclusionsPLD2/PA signaling plays an important role in pulmonary endothelial recovery from thrombin insult, and contributes to the resealing of the endothelium by stabilizing the protrusions of contiguous endothelial cells to reach out and form new adherent junctions.Support or Funding InformationThis work was supported by NIH grant HL P01 060678 Project 4 to VN.
Development and Validation of a Culturally Appropriate Heart Disease Prevention Fotonovela among Spanish Speaking Low‐income Latinos
Authors: Segura‐Pérez Sofia , Damio Grace , Galdámez Gilma , Pérez‐Escamilla Rafael 
Published: November 2023

Fotonovelas, booklet versions of soap operas that use pictures to tell dramatic stories, have been a very popular mass entertainment medium in Latin America. Fotonovelas have recently been used as an educational tool among Latinos. The main objective of this project is to describe the development and evaluation of a culturally appropriate heart disease prevention fotonovela based on the American Heart Association “The Simple Seven Steps to Prevent Heart Disease” targeting Spanish speaking Latinos. These steps promote controlling blood pressure, blood cholesterol, blood sugar, and weight as well as getting active, eating better, and stopping smoking. Mixed‐methods community‐based participatory research was used for development and evaluating the fotonovela. To be included, participant's had to be ≥18 years old, Latinos, residents of Hartford and; able to read and write Spanish. The formative qualitative research consisted of three phases. First, two focus groups were conducted with 22 participants to assess the face validity, and to obtain community input about the best way to design the fotonovela plot and format to deliver the target messages. Data from these two focus group was used to develop a first draft of the fotonovela. The second phase involved testing the face validity of the draft fotonovela through a third focus group with 4 participants who were part of the two initial focus group. In the third phase of the study the face validity of the fotonovela was confirmed with a new group of 14 participants recruited to participate in a fourth focus group. Focus groups participants were mostly female (81%) were on average 37±17 years old, 31% had completed high school or more, 50% were unemployed and 75% were receiving SNAP benefits. The knowledge, attitude, and planned behavior evaluation was conducted with 100 individuals answering a survey before and after reading the fotonovela. Knowledge was assessed with an 8‐item questionnaire designed for this study. Of these participants, 84% were female who were on average 42.5±15.1 years old, 78% primarily spoke Spanish, 28% had less than high school education and 61% were SNAP participants. After reading the fotonovela, participants increased their knowledge on the seven steps for heart disease prevention significantly (63.7±16.3 pre‐test vs 78.8±13.1 at post‐test, p=0.000), and almost all were highly satisfied with it (96%). After reading the fotonovela, when participants were asked to mention at least three steps that they would commit to follow, 93% wanted to be more active (93%), 98% wanted to eat better, 76% to avoid smoking, 28% to control blood sugar, and 24% to control their cholesterol levels. In conclusion, this culturally and literacy appropriate increased knowledge had strong face validity and may help motivate Latinos to take steps to prevent heart disease.Support or Funding InformationFunded by the American Heart Association