bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contributions of TRPA1, TRPV1 and ROS to Neuronal Activation Following Mitochondrial Modulation with Antimycin A
Authors: Stanford Katherine , Barannikov Ivan , Taylor‐Clark Thomas 
Published: June 2021

Mitochondrial dysfunction is linked to inflammatory nociceptive disorders which involve sensory nerve hyperexcitability. Inflammatory signaling pathways including interleukin‐1beta and tumor necrosis factor alpha induce mitochondrial dysfunction, resulting in mitochondrial reactive oxygen species (ROS) production, mitochondrial depolarization, and calcium release which influence cellular signaling. However, it is not known how these mitochondrial signaling events may influence nociception. Transient receptor potential channels (TRP) Ankyrin 1 (TRPA1) and vanilloid 1 (TRPV1) are selectively expressed in nociceptive subtypes of vagal, trigeminal and dorsal root afferents and play critical roles in inflammation‐associated nociception. However, the mechanism by which TRPA1 and TRPV1 contribute to nociception downstream of mitochondrial dysfunction is unknown. Our lab has previously demonstrated that Antimycin A, a mitochondrial electron transport chain complex III inhibitor, activates bronchopulmonary C‐fibers through the gating of TRPA1 and TRPV1. Here we evaluated the contributions of TRPA1, TRPV1 and ROS to neuronal activation during treatment with Antimycin A using live cell imaging of dissociated vagal mouse neurons and transfected HEK293 cells. We used calcium imaging (FURA‐2AM) to determine the activation of these non‐selective cation channels. Antimycin A selectively activated a portion of nociceptive wild‐type neurons while failing to activate non‐nociceptive neurons. With TRPV1 inhibition (iodoresiniferatoxin) or knockout the magnitude of calcium flux in responding neurons was unchanged while the percentage on neurons responding was decreased. Conversely, with TRPA1 inhibition (A967079) or knockout, the magnitude of calcium flux in responding neurons was decreased while the percentage of neurons responding was unchanged. Using both the TRPA1 and TRPV1 inhibitors together or a combination of knockout and inhibitor, responses to Antimycin A were abolished. In both TRPA1 and TRPV1 transfected HEK293 cells, a substantial portion of cells exhibited a significant increase in cytosolic calcium. To evaluate the contribution of ROS to the mitochondrial dysfunction‐evoked TRP channel activation, we scavenged ROS with dithiothreitol (DTT), a reducing agent. DTT diminished the calcium response in TRPA1 but not TRPV1 transfected HEK293 cells. In vagal neurons, MnTMPyP (cell permeable superoxide dismutase/catalase mimetic) and Tempol (superoxide dismutase mimetic) largely abolished the response to Antimycin A in TRPA1 knockout neurons. These data suggest that modulation of mitochondrial function activates nociceptive neurons via TRPA1 through a ROS‐mediated and TRPV1 through a ROS‐independent mechanism.Support or Funding InformationNational Heart Lung and Blood InstituteThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
A Novel Mitochondrial Fission Inhibitor Ameliorates DSS and DNBS Induced Murine Colitis
Authors: Goudie Luke J. L. , Mancini Nicole , Blote Karen R. , Wang Arthur , McKay Derek M. , Shearer Jane 
Published: June 2021

SignificanceInflammatory bowel disease (IBD) encompasses a group of disorders that involve an exaggerated immune response to intestinal microbes. Maintenance of intestinal epithelial barrier function is highly dependent on normal mitochondrial networks. When the barrier is compromised, excessive pathological fission ensues via the enzyme dynamin related protein‐1 (DRP1) and its interaction with the receptor fission protein‐1 (Fis1), creating fragmented networks of mitochondria. Fragmented mitochondrial networks have impaired respiratory capacity, generate elevated reactive oxygen species and exacerbate inflammationObjectiveTo determine whether a novel peptide, P110, can mitigate dextran sodium sulfate (DSS) and dinitrobenzene sulfonic acid (DNBS) induced colitis by inhibiting DRP1 and Fis1 mediated fission in murine models.DesignHypothesising that elevated mitochondrial fission occurs in DSS and DNBS colitis, male Balb/c mice were split into control (n=15), P110 (3 mg/kg/d, intraperitoneally)(n=8), DSS (5% (w/v), 5 days + 3 days water)(n=16) and DSS+P110 (n=16). For the DNBS protocol, male Balb/c mice were divided into control (n=8), DNBS (3 mg/kg/d, intraperitoneally)(n=11) and DNBS+P110 (3 mg/kg/d, intraperitoneally)(n=8). Experimental measures included: body mass, colon length, macroscopic disease score, cross‐sectional histopathology and colonic motility.ResultsUpon necropsy DSS and DNBS treated mice displayed the characteristic signs of colitis associated with these models. Disease was substantially less in both DSS+P110 and DNBS+P110 treated mice as gauged by: (i) percent weight loss (ii) macroscopic disease score and (iii) colon shortening (p<0.05). Functional improvements in colonic motility were seen in P110 treated mice when compared to DSS alone (p<0.05). Analysis of histopathology on H&E stained sections of mid‐colon revealed significant improvement in DNBS mice with P110 (p<0.05). P110 was also found to improve survival rate of mice, compared to DNBS alone.ConclusionsSystemic administration of a selective inhibitor of mitochondrial fission (P110) reduced the severity of disease in two different, commonly used murine models of colitis. Future studies are required to define the mechanism of P110's action in terms of the target cell in IBD (e.g. epithelium, nerve, macrophage). We conclude that inhibition of DRP1 and Fis1 interaction provides a novel approach to mitigating gut barrier deterioration in IBDSupport or Funding InformationCrohn's and Colitis Canada. The authors wish to thank Daria Mochly‐Rosen for donating P110.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Effect of Gut Bacterial β‐Glucuronidase on Serum Bilirubin Levels
Authors: Stout Jacob , Hankins Michael , Stec David 
Published: June 2021

The results of several large population studies have consistently demonstrated an inverse correlation between serum bilirubin levels and the development of cardiovascular and metabolic diseases. The goal of this study was to test the hypothesis that increased bacterial β‐Glucuronidase (β‐glu) activity can increase the levels of serum bilirubin by decreasing conjugation of bilirubin in the gut. Two strains of Lactobacillus acidophilus with different levels of β‐glu activity, NCK 56 (control) and NCK 2136 (constitutive overexpression), were grown and administered to mice once per day for five days. Each mouse was then administered 2 mL of fluid containing 500 million cells/ml via gastric gavage. Plasma samples were obtained prior to and after treatment. Serum bilirubin levels were measured using a specific assay kit via absorption at 700 nm. Serum bilirubin levels were similar in both groups prior to treatment averaging 2.3 +0.1 and 2.1 + 0.2 mg/dL in 56 and 2136 treated mice, respectively (n=3/group, p=0.8). Five day treatment of mice with control 56 L. acidophilus resulted in a significant decrease in serum bilirubin levels to 1.7 + 0.5 mg/dL (p<0.05), while treatment with β‐glu overexpressing L. acidophilus did not change serum bilirubin levels which averaged 2.3 + 0.3 mg/dL. Our results demonstrate that β‐Glu expression by modified L. acidophilus prevented the decrease in bilirubin that is seen upon administration of the control L. acidophilus bacterial strain. Overexpression β‐glu in a different host bacteria species with less reducing activity may provide a way to elevate serum bilirubin levels.Support or Funding InformationHearin Support Foundation, Medical Student Research Program, University of Mississippi Medical Center School of Medicine. National Heart, Lung, and Blood Institute, IP01HL‐051971. National Institute of General Medical Sciences, P20GM‐104357.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Probiotic Lactobacilli Improves Intestinal Motility in Mice
Authors: CHANDRASEKHARAN BINDU , Saeedi Bejan , Alam M Ashfaqul , Neish Andrew S. 
Published: June 2021

RationaleGastrointestinal (GI) motility is orchestrated by the enteric nervous system (ENS) organized into 2 main plexi‐sub mucosal and the myenteric plexi. Terminal differentiation of the ENS in the postnatal period is closely linked to the presence of microbiota.AimThe goal of this study was to examine if probiotics like Lactobacillus rhamnosus GG (LGG) can modulate pErk signaling in the ENS, b) regulate neuronal proliferation and/or differentiation, and thereby c) improve GI motility.MethodsThe conventional (Conv) and germ free (GF) mice were gavaged with Hanks buffer (negative control), LGG or LGG ΩSpa C (adhesion mutant of LGG). The mice were sacrificed after 2 h, and the jejunum was cryofixed and immunostained for phospho‐Erk (p44/42 MAPK, mitogen activated protein kinase). Ileum was assayed for gene expressions of neuropeptides and Hand‐2 (transcription factor regulating neuronal differentiation) by real time polymerase chain reaction (qRT‐PCR). In addition, mice gavaged with LGG, were also intra peritoneally injected with a fluorescent hydro‐cy3 dye, and production of reactive oxygen species (ROS) was assessed in the longitudinal muscle myenteric plexus (LMMP) by confocal imaging after 2 h. The conventional mice were also gavaged daily with Hanks buffer or LGG or LGG ΩSpa C for 1 week, and motility was assessed from stool frequency (stool pellets per hr) and total gastrointestinal transit time (from red carmine dye assay).ResultsWe observed that levels of pErk, Hand‐2, choline acetyl transferase (ChAT) and serotonin reuptake transporter (SERT) were significantly reduced in GF mice as compared to the Conv mice. LGG gavage resulted in enhanced phosphorylation of myenteric neuronal Erk at 2 h in both GF and Conv mice as observed from immunostaining and confocal microscopy. Further, LGG induced an upregulation of Hand‐2, and neuropeptides like ChAT and SERT in the ileum of both GF and Conv mice. The adhesion mutant LGGΩSpaC exhibited significantly reduced capacity to induce ROS, pErk, Hand‐2 and ChAT as compared to LGG in Conv mice. We observed that daily gavage of LGG, but not LGG ΩSpaC, for 1 week significantly improved gastrointestinal motility in mice as evident from motility assays.ConclusionsOur study indicates LGG can induce neuronal differentiation via ROS‐pErk signaling, and thereby improve GI motility. Hence supplementation of probiotics in the diet is beneficial for people with gastrointestinal motility disorders.Support or Funding InformationSupport: R01AI064462, R01DK089763This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Profiling Mitochondrial Quality Control in Human Myotubes Derived from Severely Obese Non‐diabetic and Type 2 Diabetic Patients
Authors: Gundersen Anders , Park Sanghee , Dubis Gabe , Houmard Joseph , Zou Kai 
Published: June 2021

Mitochondrial networks are maintained via integration of mitochondrial quality control processes, including biogenesis, fusion/fission dynamics and mitophagy. There is evidence to suggest that mitochondrial quality control plays a critical role in the regulation of mitochondrial function and glucose metabolism in skeletal muscle, and disruptions of these processes accompany the presence of skeletal muscle insulin resistance and type 2 diabetes (T2D). However, whether disruptions of mitochondrial quality control processes are retained at the muscle cell level is largely unknown. The purpose of this study was to determine whether the expression of proteins involved in mitochondrial quality control processes were dysregulated in primary human myotubes derived from type 2 diabetic patients. Primary human skeletal muscle cells were isolated from muscle biopsies obtained from eight severely obese, non‐diabetic subjects (BMI = 52.4 kg/m2, fasting glucose = 98.9 mg/dl) and eight severely obese, type 2 diabetics (BMI = 49 kg/m2, fasting glucose 132.3 mg/dl), and were differentiated to myotubes. On day 7 of differentiation, myotubes were harvested for immunoblot analysis to assess the expression of proteins involved in each of the four mitochondrial quality control processes. Mitochondrial fusion protein expression (Optic Atrophy Protein 1 (Opa1) and Mitofusin 1 (Mfn1)) were significantly lower in myotubes derived from type 2 diabetic patients in comparison to the BMI‐matched, non‐diabetic subjects (0.038 ± 0.003 vs. 0.024 ± 0.002 and 0.440 ± 0.042 vs. 0.320 ± 0.038, respectively, P < 0.05). In addition, expression of the mitophagic protein Parkin was significantly lower in primary myotubes derived from type 2 diabetic patients (0.0028 ± 0.0003 vs. 0.0018 ± 0.0002, P < 0.05). No significant differences were found in expression of other fusion or mitophagy proteins (Mitofusin 2 (Mfn2), or PTEN‐Induced Putative Kinase 1 (PINK1)), or proteins related to mitochondrial fission (dynamin related protein 1 (Drp1) and mitochondrial fission 1 protein (Fis1)), and biogenesis (PGC‐1α). These data suggest that mitochondrial quality control is dysregulated in primary myotubes derived from type 2 diabetic patients in a manner that favors fission over fusion.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
TRPV4 channel deletion or pharmacological inhibition protects heart against adverse remodeling post‐myocardial infarction
Authors: Adapala Ravi kumar , Kanugula Anantha , Minasyan Ashot , Cappelli Holly , Paruchuri Sailaja , Meszaros J Gary , Thodeti Charles K. 
Published: June 2021

Ischemic heart disease (IHD) is the major underlying cause of myocardial infarction (MI), scarring, and hypertrophy leading to heart failure. Cardiac remodeling following myocardial infarction involves scar formation by synthesis and reorganization of ECM which is mediated by myofibroblasts. We have previously shown that the mechanosensitive ion channel TRPV4 (transient receptor potential vanilloid channel 4) regulates cardiac fibroblast differentiation into myofibroblasts via integration of soluble and mechanical signaling. However, the physiological or translational significance of TRPV4 in cardiac remodeling following MI is unknown. To determine this, we have subjected WT and TRPV4KO mice to MI (permanent LAD ligation). 2D‐echocardiography revealed that the cardiac function (ejection fraction and fractional shortening) is preserved post‐MI in TRPV4KO mice compared to WT mice. Further, we found reduced fibrosis at infarcted and remote zones in TRPV4KO‐MI hearts compared to WT‐MI and sham hearts. Furthermore, TRPV4KO hearts exhibited decreased cardiomyocyte apoptosis (TUNEL assay) and increased capillary density (CD31 staining) post‐MI compared to WT hearts. To explore the translational significance of these findings, in separate experiments, we have given an orally active TRPV4 antagonist GSK2193874, immediately after MI surgery and followed for 5 weeks. Cardiac function analysis revealed that both ejection fraction and fractional shortening were preserved in GSK2193874‐treated WT mice compared to either WT or vehicle treated mice. Our results thus suggest that targeting TRPV4 protects the heart from myocardial infarction‐induced damage by preserving cardiac structure and function via reduced myocyte apoptosis, diminished fibrosis and increased revascularization, and identifies TRPV4 as a novel therapeutic target for heart failure.Support or Funding InformationNIH (1RO1HL119705), NIH (1R15CA202847‐01).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effects of Chronically Inhaled Nicotine on Cardiac Function
Authors: Oakes Joshua , Fuchs Robert , Basting Tyler M. , Lobell Thomas D. , Gilpin Nicholas W. , Lazartigues Eric , Yue Xinping , Gardner Jason D. 
Published: June 2021

Nicotine is the addictive chemical in tobacco‐related products, such as cigarettes, water pipes, e‐cigs, and chewing tobacco. While the effects of smoke from cigarettes and cigars are well known, the rise in popularity of smokeless electronic cigarettes (e‐cigs) brings new questions about the effects of nicotine itself on the development of cardiovascular disease. These “smoke‐less” products have grown in popularity due to reduced costs, increased social acceptance, and a belief that e‐cigs are a less dangerous alternative to smoking, but very little is known about the cardiac effects of chronically inhaled nicotine.Thus the goal of our study is to investigate the effects of chronic nicotine exposure on cardiac function.C57BL/6 female mice aged 20 weeks were used in this study. Mice were exposed to nicotine vapors using a nicotine exposure chamber, in which home cages are placed in sealed chamber that provide control of air flow, chronicity, and nicotine vapor dose. Mice are exposed for 12 hours/day corresponding with the dark cycle during which they are active. Female mice exposed to nicotine vapor for five weeks showed a significant increased mean arterial blood pressure from baseline, (94.3 ± 1.1 mm Hg at baseline vs. 102.4 ± .1.8 mm Hg at five weeks; p<0.001). In addition, after five weeks nicotine exposure females were found to have decreased cardiac output (18.41 ± 2.23 ml/min for air exposed mice vs. 16.17 ± 2.08 ml/min for nicotine exposed mice; p<0.05) as well as thinner posterior walls at diastole (0.71 ± 0.1 mm for air exposed mice vs. 0.64 ± 0.1 mm for nicotine exposed mice; p<0.05).These findings suggest that nicotine inhalation alters cardiovascular function, leading to increased mean arterial blood pressure, reduced cardiac output, and thinned cardiac walls. This data indicates that nicotine may play a role in cardiac functional and structural decline. Potential future directions include investigating modulators of blood pressure, such as the renin‐angiotensin system, and measuring expression levels of pathways known to adversely regulate cardiomyocyte size, such as Atrogin‐1 and MuRF‐1, following nicotine exposure.Support or Funding InformationNIH NHLBI R01 HL135635This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Eight weeks of slow deep breathing training alters cardiorespiratory function and improves functional exercise capacity in chronic heart failure patients
Authors: Lewis Robert , Seo Yaewon , Hackfort Bryan T. , Pozehl Bunny , Schultz Harold D. 
Published: June 2021

Patients with chronic heart failure (CHF) display autonomic imbalance characterized by excessive sympathoexcitation and reduced vagal outflow. Respiratory sinus arrhythmia (RSA) and baroreflex sensitivity (BRS) are often used as non‐invasive indices of autonomic function. Slow deep breathing (SDB) has been shown to modulate RSA and BRS. In this preliminary study, we examined the effects of SDB in CHF patients (n=4) during a baseline condition of spontaneous breathing (5 minutes), during SDB (5 minutes) controlled at 6 breaths/minute, and during a post‐SDB condition of spontaneous breathing (5 minutes). The patients then underwent an SDB training protocol, in which SDB was practiced at least 5 days/week and with the duration of practice incrementally increasing from 10 min/day at week 0 up to 30 minutes/day by week 8. Comparisons in cardiorespiratory function were made between each of the conditions (i.e., baseline, SDB, and post‐SDB) and between each time point (i.e., week 0 and week 8). We hypothesized that acute SDB would transiently decrease blood pressure, increase BRS, and increase RSA compared to the baseline and post‐SDB conditions. We also predicted that 8 wks of SDB training would decrease baseline blood pressure, increase BRS, and increase RSA compared to week 0. SDB produced a statistically significant (p=0.01) reduction in systolic pressure after 8 wks (114 ± 5.4 mmHg) compared to week 0 (132 ± 12 mmHg). Further, 8 wks of SDB training appears to have altered acute blood pressure responses to SDB. During SDB at week 0, systolic pressure did not differ from baseline spontaneous breathing. However, after 8 wks of SDB training, patients showed a 5.4% reduction in systolic pressure to acute SDB compared to baseline spontaneous breathing (p=0.02). The decrease in systolic pressure was not correlated with the type or dose of antihypertensive drugs. Acute SDB also produced a transient increase in BRS of ~25% from the baseline condition with no differences between week 0 and week 8. RSA increased during acute SDB compared to baseline (p=0.001) but did not change after 8 weeks of SDB training. Further, a six‐minute walk test was performed to assess functional exercise capacity, and the patients with the greatest impairment at baseline showed improvements in the six‐minute walk test after 8wks of SDB. While the data are preliminary, the results suggest that SDB training improves exercise capacity and produces a stable reduction in systolic pressure and transient change in non‐invasive measures of autonomic function in CHF patients.Support or Funding InformationNIH PO1‐HL062222‐17This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.