bluuebunny/crossref_metadata_2025 huggingface dataset:
Loss of Muscle IGF‐I Production Delays Functional Recovery of Skeletal Muscle Following Disuse
Authors: Spradlin Ray Allen , Vassilakos Georgios , Matheny Michael , Jones Nathan C , Goldman Jessica , Lei Hanqin , Barton Elisabeth R
Published: June 2021

Purpose

Insulin‐like growth factor‐I (IGF‐I) is an important coordinator of muscle growth, repair, and functional capacity while disuse‐induced skeletal muscle atrophy is a consequence of many diseases and injuries that require prolonged rest. It is known that a lack of muscle activity results in loss of skeletal muscle mass and force generating capacity but it is unclear if locally produced IGF‐I is necessary for recovery from disuse.

Methods

Mice with muscle‐specific inducible deletion of IGF‐I (MID) and age‐matched controls (CON) underwent hindlimb suspension (HLS) and reloading. Deletion was achieved by the addition of 2mg/mL doxycycline hyclate with 5% sucrose to the mice's drinking water prior to suspension and maintained throughout the course of the experiment. Mice were either left non‐suspended (NS) or suspended for 7 days (SUS) and reloaded for 3 days (Re3), 7 days (Re7), and 14 days (Re14). EDL and soleus muscle function were assessed at each timepoint and tissues were harvested to assess extent of Igf1 deletion, as well as changes in mass, gene expression (qPCR), and IGF‐I content (ELISA). All groups were compared to NS CON mice.

Results

Throughout the duration of the experiment, neither MID or CON mice's body weight changed significantly. During suspension, CON mice exhibited a 20% reduction in soleus mass and no changes for the EDL when normalized to body weight. No normalized mass changes in either muscle were seen in the MID group following suspension. Force generating capacity in CON mice was unaffected by suspension/reloading, while MID mice had a 20 and 23% reduction in specific force for the EDL and soleus, respectively, in SUS and Re7 mice. CON mice showed a reduction of muscle IGF‐I content upon suspension, a marked increase at Re7, and a return to baseline values by Re14. MID mice showed a trend for lower initial IGF‐I levels and remained reduced throughout the course of the experiment. Fiber type distribution and cross‐sectional area did not seem to be significantly affected by Igf1 deletion or suspension/reloading. Fbxo40, Musa1, and Smart expression were unchanged while endogenous Igf1 expression was significantly lower at Re7 in the MID mice compared to CON.

Conclusions

We conclude that a local source of IGF‐I is necessary for muscle recovery from disuse.

Support or Funding Information

This study was supported in part by U54 AR052646

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Identification and Characterization of Protein Phosphatase Methylesterase 1 (Ppme1) in Skeletal Muscle
Authors: Labuzan Sydney , Waddell David
Published: June 2021

Skeletal muscle atrophy results from a range of physiological conditions, including immobilization, denervation, glucocorticoid treatment, cancer, and aging. To provide a better understanding of the pathway of skeletal muscle atrophy, a previous study conducted a microarray analysis of muscle from mice undergoing neurogenic atrophy in response to denervation as well as dexamethasone exposure. The data generated from this microarray identified a suite of several hundred predicted genes that displayed differential expression under conditions of muscle wasting, including protein phosphatase methylesterase‐1 (Ppme1). The Ppme1 gene was observed to be transcriptionally upregulated in response to neurogenic skeletal muscle atrophy (i.e. denervation). To confirm that Ppme1 is expressed in muscle, qPCR was performed using RNA isolated from cultured muscle cells at different stages of proliferation and differentiation and expression was found to be relatively constant in both proliferating and differentiated cells. In addition, Ppme1 protein levels were analyzed by Western blot analysis and found to be expressed at a constant level at different time points throughout muscle cell proliferation and differentiation. Additionally, the cDNA of Ppme1 was fused in frame with GFP and subcellular localization was analyzed by confocal fluorescent microscopy in proliferating myoblasts. To assess the transcriptional activity of the Ppme1 gene, fragments of the promoter were cloned, fused to a reporter gene, transfected into C2C12 cells, and found to be highly transcriptionally active. Interestingly, the Ppme1 reporter gene constructs were not significantly affected by ectopic expression of myogenic regulatory facts such as MyoD1 and myogenin. Finally, mouse myoblast cells treated with an inhibitor of Ppme1 displayed reduced AP‐1 reporter activity as well as delayed muscle cell differentiation. The results presented here help contribute new insights into the molecular mechanisms of muscle atrophy and may provide a better understanding of the genome‐wide transcriptional changes and cellular events that occur during skeletal muscle wasting.

Support or Funding Information

The work was support by University of North Florida Transformational Learning Opportunity grants and a University of North Florida Foundation Board Grant to D.W.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Probiotics Ameliorate Gut‐Microbial Dysbiosis, Intestinal Permeability, Systemic Inflammation, and Skeletal Muscle Dysfunction in Cystathionine‐β‐synthase‐Deficient Mice
Authors: Behera Jyotirmaya , Ison Jessica , Tyagi Suresh C , Tyagi Neetu
Published: June 2021

Recent studies have reported that dietary supplementation of probiotics is a novel approach for enhancing skeletal development and metabolism in both humans and animals. However, the precise role of probiotics in regulating skeletal muscle mass at the cellular and molecular levels in mice still needs to be clarified. Here we show that altered gut‐microbiota eubiosis, systemic inflammation and skeletal muscle dysfunction caused by hydrogen sulfide deficiency and whether the intragastric administration of probiotics (GSL#5) could retard H2S deficiency‐related skeletal muscle defects. To test this hypothesis, we employed 8‐week‐old female wild‐type (WT), cystathionine‐beta‐synthase heterozygote knockout (CBS+/−), and CBS+/− mice supplemented with probiotics (GSL#5) at the dosage of 1×109 CFU every other day through oral gavage for 6 weeks. In the murine model, H2S deficiency (CBS+/− mice) increased gut permeability, and upregulated the inflammatory cytokines TNFα (TNF), and IL‐17 in the blood and the skeletal muscle. Further, the gut microbiota is significantly altered in CBS‐deficient mice as assessed by the Denaturing gradient gel electrophoresis (DGGE) analysis. We documented that long non‐coding RNA‐PVT1 (lncRNA‐PVT1) is, indeed, upregulated in the soleus muscles of CBS‐deficient mice (4.2 fold), as assessed by RT2 lncRNA qPCR Assay. The mechanistic study shows that depressed H2S signaling stimulates the transcription factor C/EBP‐α binding to the promoter of lncRNA‐PVT1 and promotes the expression of lncRNA‐PVT1. Using an electrophoretic mobility shift assay and chromatin immunoprecipitations, we identified that lncRNA‐PVT1 interacts with TNFAIP3 interacting protein 1, TNIP1, leading to the acetylation of NF‐κB (P65 subunit) activity in the soleus muscle of CBS‐deficient mice. Further, activation of P65 region of NF‐κB transcriptionally upregulates atrogin‐1, MuRF‐1 expression. Overexpression of lncRNA‐PVT1 in cultured C2C12 muscle cell lines stimulates an increase in MuRF‐1 (2.3‐fold) and atrogin‐1 (3.7‐fold) expression. In addition, systemic delivery of synthetic lncRNA‐PVT1 in control mice causes the myofibers to undergo atrophy. Gene knockout of lncRNA‐PVT1 in CBS‐deficient mice attenuates atrophy of the myofibers and muscle wasting. Overall, administration of probiotics in CBS‐deficient mice reverses the gut‐microbiota dysbiosis and preserves skeletal muscle mass. In conclusion, our findings provide novel evidence that the administration of probiotics could balance the gut‐microbiota homeostasis as well as skeletal muscle function by modulating systemic inflammation in H2S‐deficient mice

Support or Funding Information

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Differentiation Kinetics of Chronic Hypoxia Hematopoietic Stem Cells
Authors: Merritt Carlen Glen , Deskins Seth , Lawag Abdalla , Bacon Nick , Sollars Vincent
Published: June 2021

In vivo, stem cells can be found in hypoxic niches within bone marrow, peripheral blood, and umbilical cord blood. Stem cells grown in hypoxic conditions, which contains an oxygen level of up to 1%, cause them to utilize glycolysis as the primary source of energy, as opposed to stem cells cultured in normoxic conditions that use both glycolysis and oxidative phosphorylation. Differentiation requires a significant amount of energy, and previous research has shown that hydroxide radicals leaked from mitochondria inhibit phosphatases and stimulate differentiation. EML cells are a stem cell factor dependent murine hematopoietic stem cell line often used to study differentiation of blood cells. In our study, EML cells were allowed to differentiate in normoxia, chronic hypoxia and acute hypoxia conditions. We observed the effects that each of the conditions have on the differentiation kinetics by using antibodies to label the cell surface markers against: Sca‐1, CD117, CD48, CD135, CD150, CD11b, CD127, F4/80, Ter119, Ly6‐G/C. Chronic hypoxia EML cells differentiation kinetics were significantly altered. Also, labeling cells with fluorescent antibodies allowed us to trace the lineage of the induced differentiated cells, by using flow cytometry. We found that EML cells cultured in chronic hypoxic conditions had a shift in its multi‐potential progenitor (MPP) subtype, MPP4 to MPP3, that the other conditions did not. Further investing the differentiation kinetics of chronic hypoxia could lead to a better understanding on producing long term hematopoietic stem cells in vitro, for stem cell transplantation in healthcare.

Support or Funding Information

My research project began November 2017 and is ongoing, and is part of Dr. Sollars' laboratory project that is funded by NIH 1R15CA186017.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Acute exposure to high‐induction electromagnetic field affects activity of model peripheral sensory neurons
Authors: Dittert Ivan , Prucha Jaroslav , Krusek Jan , Sinica Viktor , Kadkova Anna , Vlachova Viktorie
Published: June 2021

Exposure to repetitive low‐frequency electromagnetic field (LF‐EMF) shows promise as a non‐invasive approach to treat various sensory and neurological disorders. Despite considerable progress in the development of modern stimulation devices, there is a limited understanding of the mechanisms underlying their biological effects and potential targets at the cellular level. A significant impact of electromagnetic field on voltage‐gated calcium channels and downstream signaling pathways has been convincingly demonstrated in many distinct cell types. However, evidence for clear effects on primary sensory neurons that particularly may be responsible for the analgesic actions of LF‐EMF is still lacking.

Here, we used F11 cells derived from a fusion between mouse embryonic neuroblastoma and rat dorsal root ganglion (DRG) neurons as an authentic in vitro model of peripheral sensory neurons. These cells retain many features of native DRG neurons, including expression of neuropeptide receptors and various voltage‐gated channels (Vetter a Lewis, 2010, Yin et al., 2016). Using calcium‐imaging, we examined the effects of three different protocols of high induction electromagnetic stimulation on F11 chemical responsiveness and spontaneous activity. We show that short‐term (< 180 s) exposure to LF‐EMF reduces calcium transients in response to bradykinin, a potent pain‐producing inflammatory agent formed at sites of injury. Moreover, we characterize an immediate and reversible potentiating effect of LF‐EMF on neuronal spontaneous activity. Our results provide new evidence that electromagnetic field may directly modulate the activity of sensory neurons and highlight the potential of sensory neuron‐derived cell line as a physiologically relevant tool for studying the effects of LF‐EMF, and the underlying mechanisms at the cellular and molecular level.

Support or Funding Information

This work was supported by the Ministry of Health of the Czech Republic (NV16‐28784A)

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Spontaneously Hypertensive Rats is Susceptible to Bacteria Translocation from Gut to Peripheral Tissues
Authors: Zhang Bojun , Nelson James W , Bryan Robert M , Durgan David J
Published: June 2021

Cerebral small vessel disease (CSVD) is an inflammatory disease characterized by blood‐brain barrier (BBB) breakdown and neuroinflammation. We previous observed that spontaneously hypertensive stroke‐prone rats (SHRSPs) exhibit gut dysbiosis. Furthermore, transplanting SHRSPs with control gut microbiota significantly reduced makers associated with inflammation. Since the gut microbiome is a potential source of inflammation, we hypothesize that bacteria translocating from gut to brain induce neuroinflammation in CSVD. To test our hypothesis, we determined the efficiency of fluorescent‐labeled bacteria (GFP‐E. coli JJ1901, chloramphenicol resistant) translocation in WKY and SHRSP rats. A single dose of E. coli JJ1901 [≈109 colony forming units (CFUs)] was administered to WKY and SHRSP rats (11–15 weeks old) through oral gavage. Peripheral tissues, brain, and cecum content were collected 2 hours later, homogenized, and plated on culture plates. The number of CFUs was counted 24 hours later. When compared to WKY rats, SHRSP showed significantly increased bacteria translocation to peripheral tissues (liver, spleen, and abdominal adipose tissue; n=7, p<0.05). In addition, more bacteria translocation incidents were found in SHRSPs compared to WKY rats (5/7 in SHRSP vs. 3/7 in WKY). However, similar level of acute bacteria translocation to brain was observed in both groups. To assess translocation rates of the chronically colonized bacteria, as opposed to the acute effects following gavage, colonization was established in newborn rat pups by administrating E. coli JJ1901 (≈109 CFUs) to pregnant mother rats through oral gavage. Bacteria colonization in the offspring of the gavaged rats was confirmed by plating diluted fecal samples on culture plates. Colonized SHRSPs (15 weeks old) showed significantly increased bacteria translocation to peripheral tissues when compared to WKY controls. Additionally, SHRSPs demonstrated a trend towards increased translocation of E. coli JJ1901 to the brain than WKY rats. We conclude that translocation of gut bacteria can be an underlying source responsible for inflammation in pathological states.

Support or Funding Information

National Heart, Lung, and Blood Institute R01HL134838 (D.J. Durgan), and by National Institute of Neurological Disorders and Stroke R01NS080531 (R.M. Bryan)

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Cholesterol crystals increase vascular permeability by inactivating SHP2 and disrupting adherens junctions
Authors: Mani Arul Murugan , Singh Nikhlesh K. , Rao Gadiparthi N.
Published: June 2021

To understand the adverse effects of cholesterol crystals on vascular homeostasis, we have studied their effects on endothelial barrier function. Cholesterol crystals increased endothelial barrier permeability in a dose and time‐dependent manner. In addition, cholesterol crystals induced tyrosine phosphorylation of VE‐cadherin and a‐catenin, disrupting endothelial AJ and its barrier function and these effects required xanthine oxidase‐mediated H2O2 production, SHP2 inactivation and Frk activation. Similarly, feeding C57BL/6 mice with cholesterol‐rich diet increased xanthine oxidase expression, H2O2 production, SHP2 inactivation and Frk activation leading to enhanced tyrosine phosphorylation of VE‐cadherin and a‐catenin, thereby disrupting endothelial AJ and increasing vascular permeability. Resolvin D1, a specialized pro‐resolving mediator, prevented all these adverse effects of cholesterol crystals and cholesterol‐rich diet in endothelial cells and mice, respectively. Based on these observations, it is likely that cholesterol crystals via disrupting AJ increase vascular permeability, a critical event of endothelial dysfunction and specialized pro‐resolving mediators such as Resolvin D1 exert protection against these effects.

Support or Funding Information

HL074860 from NHLBI to GNR.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Age‐ and Salt‐dependent Changes in miRNA Profile in FBN rat and C57BL/6J mice: Role of sodium hydrogen exchanger regulatory factor‐1 (NHERF1)
Authors: Jain Anish , Aubee Joseph I , Thompson Karl M , Knepper Mark A , Lee Dexter L , Khundmiri Syed Jalal
Published: June 2021

Previous studies from our laboratory demonstrated decreased NHERF1 expression in aging F344. Loss of NHERF1 expression prevented dopamine‐dependent inhibition of NKA in renal PTCs from aged F344. Our laboratory demonstrated increased expression of miRNAs regulating markers of inflammation in NHERF‐1 deficient mice and rat models. We hypothesized that loss of NHERF1 expression prevents salt‐sensitive hypertension due to changes in miRNA expression regulating Na‐transporters in renal tubules. To address this hypothesis, we analyzed the miRNA expression profile in 4mo and 24mo old FBN rats and 18mo old C57BL/6J wild‐type and NHERF1 knock‐out mice fed a normal salt or 8% salt diet (HSD). Total RNA from kidney cortex was isolated using Trizol (miRVana, Ambion) and miRNA profile was analyzed using kits and software from Nanostring. The top 100 miRNAs with cut‐off set at counts three times the SD of the negative control miRNA counts were considered for analysis. Counts from normal diet fed animals (n=8, 4M4F) were averaged together and considered as 1 to calculate changes in HSD animals. In 4‐mo old FBN rats 23 miRNAs significantly increased in HSD (miR196c, miR466b, miR144, and miR142‐5p), while miR547, miR375, and 6 others significantly decreased. In 24‐mo old FBN rats 30 miRNAs increased significantly in HSD (miR‐192, miRNA141, and miR21), while 10 miRNAs decreased significantly (miR328a and miR‐let‐7a and f). Similar results were observed in WT mice. However, in NHERF‐1 KO mice the miRNAs increased strongly regulate markers of inflammation. The data was confirmed by measuring the expression of down‐stream targets using western blotting and ELISA. These data may suggest that NHERF1 plays a major role in regulation of renal inflammation and salt‐sensitive hypertension.

Support or Funding Information

7R21AG047474‐03 NIH; R25AG047843‐NIH; 16GRNT31030019‐AHA

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The increased expression of microRNAs 451, 638 and 362 in Urinary Exosomes of Human Subjects profiled as Diabetic and Hypertensive
Authors: Lewis Harvey , Smith Michael , Fluitt Maurice , Khundmiri Syed J , Ecelbarger Carolyn , Lee Dexter L
Published: June 2021

Urinary Exosomes (UE) are involved in several metabolic processes, including hypertension and are considered to be vehicles for eradicating cell waste products. UE have important functions in human diseases as carriers of information including, proteins, lipids and miRNA (mi‐R). Because of their high stability, UE mi‐Rs can be useful predictors of the progression of diabetes and hypertension. UE mi‐Rs 451, 638, 362 and 16 are potential biomarkers for early diabetic nephropathy, salt‐sensitive hypertension and cardiovascular disease, respectively. We hypothesized that mi‐Rs 451, 638, 362 and 16 are increased in diabetic + hypertensive patients when compared to controls. To address this hypothesis, human urine samples were collected from control, diabetic and hypertensive patients. UE were isolated in each group and mi‐R 451, 638, 362 and 16 expression was quantified by RT‐PCR. mi‐R expression was expressed as log2, normalized to U6 small nuclear RNA as mean and standard error. UE mi‐R 451 expression in diabetic + hypertensive patients was 2.4 ±1.8 and 0.5 ±0.8 in controls. UE mi‐R 638 expression in diabetic + hypertensive patients was 1.0 ±2.0 and 0.1 ±1.7 in controls. UE mi‐R 362 expression in diabetic + hypertensive patients was 1.9 ±1.8 and 0.2 ±0.8 in controls. UE mi‐R 16 expression in diabetic + hypertensive patients was similar to the controls (0.1 ±10 and −9 ±1, respectively). Our results suggest that both mi‐R 451, 638 and 362 expressions are increased in diabetic + hypertensive patients. There was not an increase in UE mi‐R 16 in diabetic + hypertensive patients when compared to controls. In conclusion, mi‐R 451, 638 and 362 expressions may serve as non‐invasive biomarkers for the early detection for diabetes and hypertension.

Support or Funding Information

R25AG047843‐NIH

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Differential Nuclear Localization of SOX18 Variants in Transiently Transfected Epithelial Cells
Authors: Cvammen William , Prokop Jeremy W. , Qutob Dinah , Freeland Thomas , Underwood Adam
Published: June 2021

Sry‐related box (SOX) proteins are transcription factors containing a conserved High Mobility Group‐box (HMG‐box) DNA‐binding domain that regulate embryogenesis and tissue maintenance. SOX mutations result in cancer, developmental abnormalities, sex reversal, and circulatory dysfunction. Genomic analysis of the 20 human SOX genes identified 3,049 variants from gnomAD and 1,566 from COSMIC with an enrichment of variants that falls within the HMG box. The most impactful variant identified occurred in the third alpha helix of the SOX18 HMG‐box that replaces a glutamic acid (E) for a lysine (K) (rs201931544). Since other variants occurring within the HMG box of SOX18 are linked to vascular and lymphatic disfunction, we predict SOX18 E137K will also derange protein function through altered DNA interaction and localization to the nucleus. No literature exists regarding E137K, although it is present in 0.8% of Latino population. The purpose of this project was to produce native and mutated SOX18 expression constructs to determine if nuclear accumulation is impacted. Native human SOX18 was first cloned into pHTCHaloTag® CMV‐neo vector (Promega), followed by site‐directed mutagenesis to synthesize pHTCHalo/SOX18‐E137K. After sequence confirmation, human dermal lymphatic endothelial cells, HeLa and A375 were transiently transfected with either the native or mutated construct, or a control vector (pHTCHaloTag® CMV‐neo vector with no insert), in glass chamber slides. After 24hr, live cells were incubated with HaloTag® Oregon Green® Ligand (Promega) and micrographs were captured on an Olympus iX51 with DP71 digital camera. Controls showing cytochemistry specificity include cells transfected with SOX18 incubated with PBS in place of Oregon Green® Ligand. From these trials, it was determined that E137K reduces nuclear localization of SOX18 in all cell lines and may account for divergent phenotypic consequences when compared to native SOX18.

Support or Funding Information

Support for this study was from NIH‐K01ES025435 (to JWP) and Walsh University

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The current unrecognized epidemic of smell dysfunction in the United States
Authors: Henkin Robert
Published: June 2021

There is an estimated 21 million people with smell dysfunction in the United States. However, most people in the U.S. are unaware of the existence of this problem. Most physicians are also unaware of this problem. Indeed, there is no specific medical specialty to evaluate or treat this problem. These issues comprise an unrecognized epidemic of smell dysfunction occurring in the U.S. Smell dysfunction comprises patients with loss of smell acuity, the presence of distorted perception of external odors (aliosmia) and the presence of distorted smells in the nose in the absence of any odor (phantosmia). These symptoms most commonly occur after a viral‐type illness (about 25%), allergic rhinitis (about 20%), head injury (about 15%) and a variety of other illnesses including Parkinsonism, Alzheimer disease and other degenerative neurological disorders. The current view of the pathology which generates these symptoms is that some neurological abnormalities occurred either in the olfactory nerves or in the brain. However, recent studies have demonstrated that the underlying cause of these symptoms is not neurological in nature but usually biochemical related to loss of olfactory receptor function due to inhibition of biochemical activation and signaling in stem cells upon which olfactory cell growth and development depend. The recognition that biochemical treatment of this stem cell pathology results in activation of specific sensory cell signaling which improves smell dysfunction demonstrates the biochemical basis of this unrecognized epidemic.

Support or Funding Information

This institution did not receive any funding from agencies in the public, commercial, or not‐for‐profit sectors.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Gut Microbiome Composition Differs between Individuals with Acute and Long‐standing Traumatic Spinal Cord Injury
Authors: Li Jia , Hoover Thomas , Morrow Casey , VanDerPol William , Yarar‐Fisher Ceren
Published: June 2021

Objective

To examine the gut microbiome composition among individuals with acute and long‐standing spinal cord injury (SCI).

Methods

Seven individuals with acute spinal cord injury (A‐SCI, 36 ± 13 y, 2F/5M, C4‐T10, AIS A‐D) and 10 individuals with long‐standing SCI (L‐SCI, 49 ± 9 y, 1F/9M, C4‐T12, AIS A, B, and D ) were recruited. Stool samples were collected after a median of 7 days after the onset of SCI (range: 4–11 days) from participants with A‐SCI in the hospital. The median number of years post injury for the L‐SCI group was 22 years at the time of stool collection. Parapak® vials was used for collection of the stool samples. Fecal microbiota DNA was extracted using Zymo® Fecal DNA Isolation kit. PCR was used to amplify the V4 region of the 16S rRNA gene, and the PCR products were sequenced using an Illumina MiSeq platform. Bioinformatics analyses started with assessment of raw data and filtering low‐quality data using FASTQC and FASTX, respectively. A combination of tools in the QIIME suite were utilized for clustering reads into operational taxonomic units (uclust) and taxa assignment (PyNAST and Fasttree). Several metrics for alpha and beta diversity were determined for group comparisons. Significant differences between groups (A‐SCI vs L‐SCI) were determined by PERMANOVA test on each of the beta diversity indices. A Kruskal‐Wallis test was performed to compare the abundances of key taxa between groups using tools within the QIIME suite.

Results

Microbiota alpha diversity was not significantly different between groups. However, group differences were observed in beta diversity (unweighted and weighted UniFrac analyses, P < 0.05 for both). Principle coordinate analysis showed a separation of two groups (see attached figure). Individuals with chronic SCI had higher abundances of bacteria in the Clostridiaceae, Lachnospiraceae, and Alcaligenaceae families, lower abundances of S24‐7 family, and higher abundances of Parabacteroides genus (family Porphyromonadaceae) (P < 0.05).

Conclusion

These data for the first time demonstrated a sustained shift in gut microbiota composition in individuals with L‐SCI vs. A‐SCI. Specifically, microbes linked to the development of metabolic syndrome, central nervous system‐related bowel disorders, and physical inactivity are elevated in adults with L‐SCI. Future studies are warranted to evaluate the involvement of gut microbiota in the development of metabolic disorders among individuals with L‐SCI.

Support or Funding Information

This work was supported by KL2TR001419‐01 (CY‐F) and H133N110008 (McLain A)

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The comparative and functional anatomy of the fore‐ and hind‐limb musculature of Humboldt's woolly monkey (Lagothrix lagotricha): New insights into ape and human evolution from a (mediocre) suspensory platyrrhine
Authors: Deane Andrew Stewart
Published: June 2021

Similar to other members of the platyrrhine subfamily Atelinae, Humboldt's wooly monkey (Lagothrix lagotricha) is a ‘tail‐assisted’ brachiator that more frequently engages in non‐suspensory forms of locomotion (i.e. quadrupedal climbing). As a group the atelines share a suite of derived forelimb skeletal characters that are specialized for brachiation and that are convergent with ‘richochetal’ brachiating apes (Hylobates, Symphalangus), quadrumanus suspensory apes (Pongo) and secondarily terrestrial apes retaining suspensory capabilities (Pan, Gorilla). The skeletal anatomy of lagothrix is similar to more suspensory atelines (Ateles, Brachyteles) and living apes, but is typically less derived for suspension and many skeletal characters are intermediate between highly suspensory and non‐suspensory anthropoids. While the functional morphology of the ateline skeleton is well documented, relatively little is known about the comparative and functional morphology of the forelimb and hindlimb musculature. Specifically, can locomotor differences between Lagothrix and more suspensory atelines and hylobatids be explained, in part, as a result of differences in muscle‐tendon architecture?

This study describes preliminary quantitative data on the muscle–tendon architecture (relative muscle mass and relative physiological cross‐sectional area or PCSA) of the fore‐ and hind‐limbs of Lagothrix lagotricha and Macaca sp. (n=9). Despite infrequent brachiation, Lagothrix forelimb relative muscle mass and PCSA is identical to similar results reported for hominoids. In contrast, the relative mass and PCSA of the hind‐limb musculature is most similar to quadrupedal monkeys (i.e. Macaca). Specifically, Lagothrix resembles hylobatids in the concentration of muscle mass and force in the flexor compartments of the arm and forearm but is more similar to Macaca in similar measures associated with the extensor and flexor thigh and leg. This suggests that despite a reduced reliance on suspensory postures and brachiation, Lagothrix forelimb muscle‐tendon architecture may be, at least in part, a response to the minimum functional demands of brachiation but that similar selection pressures are not as prevalent in the hind‐limb.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Ventricular transcriptomic changes induced by cold‐acclimation in the painted turtle suggests epigenetic‐mediated transcriptional remodeling
Authors: Fanter Cornelia E , Lin Zhenguo , Warren Daniel E
Published: June 2021

Ectothermic vertebrates living at extreme latitudes are often forced to endure extended periods with their body temperatures at or just above the freezing point of water. Cold temperatures impose a number of physiological and biochemical challenges directly related to the thermodynamic effects on biological matter, including metabolic enzyme kinetics and even the physical properties of blood. The painted turtle, Chrysemys picta, is a pond turtle that can experience temperatures just above freezing for 3–5 months as adults and can tolerate freezing or even subzero temperatures as hatchlings. In the present study, we characterized how cold acclimation to 3°C affected the ventricular transcriptome in both adult and hatchling turtles. Because hatchlings must tolerate subzero temperatures when they overwinter in their nest, we sought to determine if they might also exhibit a unique gene expression pattern related to possible cryoprotective mechanisms. Despite differences in life history, adults and hatchlings responded similarly to cold acclimation at the transcriptomic level; out of the 1304 genes that were differentially expressed due to temperature, 1272 showed similar expression patterns in adults and hatchlings, the majority of which were upregulated. In adults and hatchlings combined, 776 genes were upregulated at 3°C, 550 genes were downregulated, of which 22 fell into both categories due to development‐specific expression patterns. Of these upregulated genes, 51 encoded for transcription factors, 27 for histone modification proteins, and 26 for mRNA processing and translational regulation enzymes. These results suggest that the ventricle actively remodels chromatin structure and modulates both gene expression and mRNA processing in response to cold acclimation.

Support or Funding Information

This work was supported by NSF CAREER grant 1253939 awarded to DEW

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Lentivirus‐ and shRNA‐based smooth muscle‐specific TRPC3 channel knockdown as an emerging therapeutic for asthma
Authors: Zheng Yun‐Min , Wang Yong‐Xiao
Published: June 2021

A major pathological feature of asthma is airway smooth muscle (ASM) hyperresponsiveness, which is the rationale for using bronchodilators as the first‐line therapy for asthma. The molecular mechanisms for airway hyperresponsiveness remain incompletely understood. The transcription factor nuclear factor‐κB (NFκB) is increasing known to be important for asthma. Using the TFSEARCH program, we have found that NFκB has specific binding sites on the promoter region of canonical transient receptor potential‐3 (TRPC3) channel, a crucial player for numerous pathological cellular responses in a variety of cells. Our investigations have revealed that tumor necrosis factor‐α (TNFα), an important asthmatic mediator, could significantly augment the luciferase intensity in mouse ASM cells (ASMCs) transfected with TRPC3 channel promoter/PGL3 luciferase reporter vectors, indicating an increase in the channel promoter activity. The TNFα‐induced increase in TRPC3 channel promoter activity was blocked by specific NFκB inhibition. Similarly, NFκB‐dependent increased TRPC3 channel promoter activity was observed in ASMCs from mice with allergen‐evoked asthma. We have also demonstrated that among all 7 TRPC channel members, only TRPC3 channel showed a predominant functional activity in ASMCs. TRPC3 channel gene and protein expression levels were much higher in asthmatic mouse ASMCs. More importantly, intravenous or intranasal delivery of lentiviruses encoding the SMC promoter SM22α‐driven mouse TRPC3 channel shRNAs in mice caused a sufficient knockdown of the channel expression and function in ASMCs. The TRPC3 channel knockdown mice had no asthmatic airway hyperresponsiveness. Moreover, lentiviral shRNA‐based SMC‐specific TRPC3 channel knockdown blocked ASM remodeling (known as another major asthmatic pathological feature) in asthmatic mice. Taken together, we conclude that TRPC3 channel serves as an essential mediator of the functional role of the transcription factor NF‐κB in asthma; as such, NF‐κB underlies the asthmatic increase in TRPC3 channel promoter activity, expression and function in ASMCs, leading to airway hyperresponsiveness and remodeling. Evidently, lentivirus‐ and shRNA‐based SMC‐specific TRPC3 channel knockdown is an emerging therapeutic for asthma.

Support or Funding Information

HL122865

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Distinct ion transport in the marsh rice rat (Oryzomys palustris) airway
Authors: Reznikov Leah Renee , Kuan Shin‐Ping , Liao Yan‐Shin J , Davis Katelyn , Messer Jonathan , Zubcevic Jasenka , Aguirre Jose Ignacio
Published: June 2021

Hypertonic solutions increase airway surface liquid (ASL) through cholinergically‐mediated epithelial cell ion transport and osmosis. Thus, mammals inhabiting salt marshes might have acquired adaptations, including greater dependence upon cholinergic mechanisms, for ASL regulation. To test this hypothesis, we investigated the airways of the rice rat, a medium‐sized rodent that inhabits salt marshes. We discovered unique ion transport properties, including minimal amiloride‐sensitive Na+ absorption and limited Cl− secretion through the cystic fibrosis transmembrane conductance regulator. In contrast, the cholinergic agonist carbachol induced a large Cl− secretory current that was blocked by the calcium‐activated chloride channel inhibitor CaCCinh‐A01. Rice rat airway cultures also secreted fluid in response to carbachol, and when challenged with 3.5% NaCl apically to mimic exposure to sea water aerosols, displayed a prolonged expansion of the ASL volume. These data suggest that the rice rat airway might possess unique ion transport mechanisms to facilitate survival in the harsh salt marsh environment.

Support or Funding Information

HL119560, 0T2TR001983, DE0237863

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Do Oral Contraceptives Change the Ventilatory Response to Group III/IV Skeletal Muscle Afferent Activation?
Authors: Vera Kathryn , Chantigian Daniel , Larson Mia , Keller‐Ross Manda
Published: June 2021

Background

Group III/IV skeletal muscle afferents increase ventilation (VE) during exercise. Estrogen has been show to attenuate group III/IV afferent activity. Further, oral contraceptives (OC) lower endogenous estrogen and have been shown to increase VE at rest, although the effect of OCs on VE when group III/IV afferents are activated remains unclear.

Objective

Determine the influence of OC use on VE in response to activation of group III/IV skeletal muscle afferents during steady state cycling in healthy, young women.

Methods

Fifteen women (24±2 years, mean ± SD, 8 OC‐users) completed two exercise sessions; once during the low estrogen/low hormone phase (LH, days 1–4 of the menstrual cycle for n‐OC; placebo pill for OC) and once during the high estrogen/high hormone phase (HH, days 10–14 of the menstrual cycle; active hormone pill for OC). Exercise sessions included 25 minutes of steady‐state cycling at a workload of 60W and speed of 65–70rpm. To activate group III/IV afferents, randomized sub‐systolic occlusion at three pressures (20mmHg, 60mmHg and 100 mmHg) were applied bilaterally to the proximal thigh via Hokanson cuffs (DE Hokanson, Inc., Bellevue, WA). After 3 minutes of control (CTL) exercise, cuffs were inflated for two minutes and deflated for five minutes intermittently during exercise. VE, respiratory rate (RR) and tidal volume (VT) were continuously monitored (Ultima CardiO2, MGC Diagnostics, St. Paul, MN).

Results

Sub‐systolic circulatory occlusion increased VE from baseline exercise to 100 mmHg (CTL: 27.5±3.5L/min; 100 mmHg: 33.0±3.0 L/min, p<0.001). There were no differences in relative VE (%baseline exercise) following group III/IV afferent activation among OC versus n‐OC users at pressures of 20mmHg (5.9±4.9% vs. 10.2±10.3%, respectively), 60mmHg (15.4±7.5% vs. 12.2±5.4%, respectively) and 100mmHg (22.6±8.2% vs. 19.0±7.8%; respectively, p=0.08). Relative changes in RR and VT (%baseline exercise) also did not differ among OC versus n‐OC users at with increasing cuff occlusion pressures (RR: p=0.39; VT: p=0.37).

Conclusions

Although OCs lower serum levels of sex hormones, the reduction in endogenous estrogen does not seem to influence the ventilatory response to group III/IV afferent activation in healthy, young women.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Acute Exercise Impairs Cognitive Function at High Altitude
Authors: Walsh Jeremy , King Trevor , Drouin Patrick , D'Urzo Katrina , Tschakovsky Michael , Day Trevor
Published: June 2021

Ascent to high altitude can impair aspects of cognitive function in an altitude‐dependent manner. Interestingly, a single bout of aerobic exercise transiently improves cognitive function in normobaric hypoxia, suggesting that aerobic exercise may be an effective strategy for improving brain function at altitude, but this phenomenon has yet to be explored. The purpose of this study was to investigate the effect of a single bout of aerobic exercise on cognitive function at low and high altitude in the Nepal Himalaya. Fifteen healthy volunteers (24.1±3.5yrs; 9 females) performed 20 minutes of aerobic exercise at 40–60% of their heart rate (HR) reserve at low (1400m) and high altitude (4370m) after 7 days of incremental ascent. Ascent‐related physiological data were collected in the morning before exercise including arterial blood pressure, HR, peripheral capillary oxygen saturation, hemoglobin concentration, hematocrit, end‐tidal CO2 (PETCO2), and acute mountain sickness (AMS) scores. During exercise, participants wore HR monitors in order to maintain HR within the prescribed intensity zone. Cognitive function was assessed before and 10‐min after exercise using a battery of standardized iPad‐based tests (BrainBaseline, Digital Artefacts). A 2‐factor (Time × Condition) repeated measures analysis of variance was performed to examine differences in cognitive function before and after exercise (Time) at low and high altitude (Condition). Exploratory correlations were performed to investigate the relationship between changes in physiological measures with high‐altitude ascent and during exercise and changes in cognitive function. There was a significant interaction between altitude and exercise on a test of processing speed, working memory, and visuospatial attention, such that performance worsened following exercise at high altitude (P=0.02). In contrast, task‐switching abilities and inhibitory control remained unchanged after exercise. Higher baseline hemoglobin was associated with a decline in cognitive performance following exercise at high altitude (r= −0.58, P=0.01), whereas higher baseline PETCO2 was associated with improved cognitive performance following exercise at high altitude (r=0.54, P=0.03). Interestingly, there was no relationship between AMS scores and changes in cognitive function. In conclusion, acute aerobic exercise performed at high altitude impairs some measures of cognitive function, which may be impacted by physiological acclimatization during ascent. Future work should investigate the persistence of this post‐exercise decrement in cognitive function to help inform recommendations regarding decision‐making behaviors following exercise at high‐altitude.

Support or Funding Information

NSERC Discovery, NSERC PGS, and Wilderness Medical Society Research In‐Training Award

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Imaging to Detect Abnormalities in the Innervation and Microvasculature of the Developing Heart
Authors: Ford Stephanie , Karunamuni Ganga , Sheehan Megan , Jenkins Michael W , Watanabe Michiko W
Published: June 2021

The developing heart is a challenge to image because of its small size, rapid morphogenesis, and complex 3‐D structure. Capturing function is even more challenging because the heart begins beating at an early stage. Our group has developed a suite of biophotonic tools to capture structure and function in a quail model of fetal alcohol syndrome, induced by a single administration of ethanol to the fertilized egg to mimic a first trimester binge drinking episode. The quail is a useful model because it develops a 4‐chambered heart, it is economical, and the embryos are more easily accessible than mouse embryos to biophotonic interrogation for longitudinal structure and function analysis. Ethanol exposure reduces survival and increases the prevalence of congenital malformations, including congenital heart defects. We have previously reported on structural heart defects in the outflow tract, great vessels, septation, and in cardiac valves, and we have discovered that certain compounds (e.g. betaine) can alleviate these negative effects.

Prenatal ethanol is thought to induce cardiac abnormalities by damaging neural crest cells, which may cause abnormalities in their derivatives. Many studies, including ours, have focused on the consequences of neural crest cell disruption in the formation of abnormalities of the cardiac outflow tract. In our current studies we explore how ethanol exposure may disrupt cardiac innervation, coronary vasculature, and other important derivatives of the neural crest cells.

Eggs were injected with an ethanol at gastrulation and incubated until the embryos form four chambered hearts. The heart were dissected and immunofluorescently stained as whole mounts with neuron‐specific tubulin (TUJ1) to label the autonomic innervation. Our preliminary findings demonstrate that ethanol‐treated embryos have fewer innervation branching points and ganglia on the ventral ventricular base than controls. We also found more splitting of the major nerve, the thoracic sympathetic cardiac branch of the vagus that runs along the ventral surface of the pulmonary artery. Filling the microvasculature with SLIME (Scattering Labeled Imaging of Microvascular in Excised tissues) revealed that ethanol exposure results in coronary microvascular misalignment and uneven vessel distribution. In summary, both innervation and coronary microvasculature of the heart are altered by ethanol exposure. These findings may have implications for the cardiac health risks of individuals exposed to ethanol prenatally.

Support or Funding Information

NIH R01 HL126747, NIH R01 HL083048, NIH T32 HD060537

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.