bluuebunny/crossref_metadata_2025_split huggingface dataset:
Muscle ULK1 and ULK2 modulate different aspects of autophagy and are required for atrophy during fasting
Authors: Mere Caleb , Fuqua Jordan , Blomme Jay , de Melo Vitor , Kronemberger Ana , Lira Vitor A 
Published: November 2023

(Macro)autophagy, hereafter referred to as autophagy, is an evolutionarily conserved catabolic process involving in the degradation of cellular proteins and structures sequestered into a vesicle known as an autophagosome. Impairments of autophagy have been implicated in contractile and/or metabolic deficiencies in muscle diseases, obesity, diabetes, and aging; however, regulation of skeletal muscle autophagy is poorly understood at the molecular level. Here, we examined the role of the two partially homologous unc‐51 like autophagy activating kinases 1 and 2 (ULK1 and ULK2) in modulating autophagy and myofiber atrophy during fasting via a miRNA‐specific knockdown of these proteins in mouse skeletal muscle. Suppression of ULK1 caused LC3‐I (the non‐autophagosomal‐interacting form of LC3) to accumulate in fasted muscle without changes in LC3 mRNA, indicating an impairment in the step of LC3‐I conversion into LC3‐II (the autophagosomal‐interacting form of LC3). Similar trends were observed with non‐autophagosomal and autophagosomal forms of other LC3‐like proteins (GABARAP, GABARAPL1, GABARAPL2) suggesting a specific role for ULK1 in autophagy activation. Knockdown of ULK2 did not affect the different forms of LC3 and LC3‐like proteins suggesting that ULK2 does not regulate autophagy activation. However, it led to accumulation of ubiquitinated proteins, and the autophagy receptors p62 and NBR‐1, irrespective of their mRNA, under both basal and fasting conditions. Since autophagy receptors bind to and are degraded together with ubiquitinated proteins, these findings are consistent with impaired involvement of receptors and consequent deficient cargo recognition by autophagy. Of note, reduced expression of both ULK1 and ULK2 was required to diminish myofiber atrophy during fasting, indicating their synergistic role in mediating fiber atrophy in this model. Altogether, these results uncover fundamental divergent roles for ULK1 and ULK2 in modulating autophagy and its target recognition/selectivity in muscle. Future studies expanding the molecular signature of autophagy activation and selectivity will be instrumental to identify novel targets for therapy in conditions associated with autophagy deficiency in muscle.Support or Funding InformationAmerican Heart Association Grant 16SDG30360001 (V.L.)
Autonomic cardiovascular response during post‐occlusive reactive hyperaemia test comparing healthy and sickle cell anemic patients
Authors: Carrazana‐Escalona Ramón , Sanchez‐Hechavarria Miguel Enrique , Planas‐Rodríguez Maylet , García Adolfo Fernández , Cutiño‐Clavel Ileana , Pascau‐Simon Alexander , Martín‐González Juan Manuel , Connes Philippe 
Published: November 2023

IntroductionAlthough the sickle cell disease (sicklemia) is characterized by significant m icrocirculatory dysfunction, in is not clear whether regulatory physiological phenomena associated with hemodynamic response during reactive hyperaemia post ‐occlusive test are affected.ObjectiveWe sought to determine autonomic cardiovascular responses during reactive hyperaemia post‐occlusive test in healthy and sicklemic patients.MethodsUsing a quasi‐experimental design with 25 healthy subjects and 18 sicklemic patients, we studied the effects of reactive hyperaemia on vascular and cardiac variables. Following 10 min for acclimation, we evaluated 5 min before (basal), 10 min during post‐occlusive reactive hyperaemia test on the lower right limb, while performing Pulse Rate Variability (PRV), obtained by the Pulse Peak In tervals of the photoplethysmographic signal (AngiodinÂ® PD 3000 device) on the first finger of the lower right limb. Pulse Peak Intervals were analyzed using frequency (Welch) and time‐frequency (Wavelet) methods of the bands of high frequency (HF: 0.15–0.4) and low frequency (LF: 0.04–0.15), as well as temporal and nonlinear (Sample Entropy) analysis.ResultsWe observe an increase (p<0,05) in the basal state of the suggestive indicators of sympathetic (LF, LF/HF) activity in post‐occlusive reactive hyperaemia test during the 5 first minutes, which tend to be lower in the last 5 minutes of recuperation besides a significant increase in all indicators of the PRV existed in the basal state in healthy regarding sicklemic patients. With time‐frequency analysis, we found that the LF/HF peak of response to the post‐occlusive reactive hyperaemia test occurs more rapidly in healthy compared to sicklemic patients.ConclusionsThe sympathetic cardiovascular response during post‐occlusive reactive hyperaemia test in sicklemic patients is smaller and slower than in healthy subjects, which suggest that in this disease there are physiopathologic phenomena that affect regional vascular responsiveness to ischemia.Support or Funding InformationNone
Association Between Telomere Length and Autonomic Functions: Applying Psychological and Physiological Measures
Authors: Kim Nahyun , Sung Jin Young , Kim Dae‐Kwang 
Published: November 2023

Telomeres are protective chromosomal structures that are important in maintaining genomic stability. Telomere shortening results in genomic instability and contributes to aging and carcinogenesis. Despite the health risks posed by this condition, few studies have examined the relationship of telomere length (TL) to autonomic functions. In this study, we examined the association between TL and autonomic functions in Korean adolescents. A cross‐sectional study was performed with high school adolescents in a Korean city. Self‐report questionnaires were used to assess psychological measures (stress and anxiety levels), and blood samples were analyzed for physiological parameters (plasma catecholamine levels) of the participants. TL measurements were made using a qPCR‐based technique, and relative TL was calculated as the telomere/single copy (T/S) ratio. Data were analyzed using descriptive analysis and Pearson's correlation coefficient with SPSS/WIN 22.0. We found that T/S ratio was positively correlated with plasma epinephrine and norepinephrine levels (r=.225, p=.001 and r=.187, p=.005). However, psychological stress and anxiety levels were not significantly associated with adolescents' T/S ratio. Our physiological results indicate that alteration of autonomic functions may induce TL shortening in adolescents. We believe that our findings increase the understanding of the health effects of autonomic functions. Moreover, they highlight the need for intervention strategies to prevent TL shortening due to autonomic imbalance.Support or Funding InformationThis research was supported by the Basic Science Research Program of the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2016R1D1A3B03934143).
Role of GABA Receptors in the Postganglionic Regulation of Salivation
Authors: Lee Joseph , Giovannucci David 
Published: November 2023

The salivary gland secretes saliva components critical for oral health. Autonomic neural activity controls the secretory output of acini, the basic units of saliva production. This process can be disrupted in patients by benzodiazepine treament, leading to the severe oral condition of xerostomia, or dry mouth. Neural inputs to the acini are primarily cholinergic and noradrenergic, but the discovery of gamma‐aminobutyric acid (GABA) and its receptors in the salivary glands hints at an unexplored mechanism for benzodiazepine‐induced xerostomia. In the current study, biochemical, live‐cell imaging, immunofluorescence and electrophysiological methods were used to elucidate the GABAergic system in the mouse parotid gland and define its effect on acinar regulation. RT‐PCR identified mRNA transcripts for multiple GABA receptor subunits in enzymatically dispersed acinar cells and immunofluorescence microscopy indicated the expression of GABA receptors in mouse parotid tissue. However, both live cell calcium imaging and whole‐cell recordings of acinar cells revealed no acute impact of GABA or benzodiazepine treatment on cellular physiology. In contrast, immunohistochemical analysis of the autonomic autonomic ganglia and postganglionic innervations to the parotid gland aligned with the identification and characterization of GABA‐evoked chloride currents in a subset of neurons recorded from primary ganglionic cultures. Our data suggest GABA has no direct effect on the parotid acini but may downregulate acinar function by inhibiting neurotransmitter release from autonomic neural inputs.Support or Funding InformationThis work was funded by National Institutes of Health National Institute of Dental and Craniofacial Research Grant DE‐023418 and bridge funds from the University of Toledo College of Medicine.
Rats deficient in tryptophan hydroxylase 2 (SSTph2−/− rats) show altered pulmonary neuroendocrine cells (PNECs), reduced resting ventilation and altered hypoxic and hypercapnic chemoreflexes
Authors: Mouradian Gary C , Dillard Matthew , Kaplan Kara , Thuku Gabriel , Uche Nnamdi , Hodges Matthew R 
Published: November 2023

Sudden Infant Death Syndrome (SIDS) is a leading cause of infant mortality from 1–12 months of age, and is thought to occur due to cardiorespiratory failure during sleep. The leading hypothesis as to the causes of SIDS is that abnormalities in the central serotonergic (5HT) system are underlying biological factors contributing to SIDS, but other studies report hypertrophy and hyperplasia of serotonergic lung airway chemosensors called neuroepithelial bodies (NEB) in SIDS. Herein, we tested the hypothesis that rats deficient in tryptophan hydroxylase 2 (TPH2; SSTph2−/− rats), which fail to synthesize brain 5HT, would display NEB hypertrophy and hyperplasia during post‐natal development. We further tested the hypothesis that SSTph2−/− rats would show altered ventilatory chemoreflexes during development, potentially due to altered airway chemoreceptor activity. Cryosections (20μm thick) of inflation fixed lungs were co‐stained for CGRP and Synaptophysin, standard markers of NEBs, and DAPI. Blinded imaging and subsequent analyses indicate a greater number of NEB cells in Tph2−/− rats but a decrease in overall NEB cell size compared to WT rats in 1–2, 12–13, and 18–22 day old groups. These changes correlated with significantly lower weight‐normalized minute ventilation in Tph2−/− rats during room air, hypercapnic, and hypoxic challenges at P12–13, 14–16, and 18–20 day old groups. In conclusion, loss of central serotonin appears to directly or indirectly alter the morphology of peripheral airway 5HT chemosensors.Support or Funding InformationNIH HL R01 122358
Insulin Increases Respiration Rate in Healthy Young Men
Authors: Barbosa Thales C , Holwerda Seth W , Young Colin N , Thyfault John P , Fadel Paul J 
Published: November 2023

Previous in vitro and in vivo studies in rats have indicated that carotid body chemoreceptors are capable of increasing respiration in response to acute hyperinsulinemia. Although increased respiratory rate has also been detected in humans during insulin infusion, it was accompanied by hypoglycemia, which is known to independently stimulate carotid chemoreceptors. Therefore, a hyperinsulinemic euglycemic clamp was performed to test the effect of elevated insulin on respiration rate, while glucose was maintained constant. We tested the hypothesis that elevated plasma insulin would increase respiration rate. Seventeen healthy young men [27 ± 1 years; 25.5 ± 0.7 kg m−2 (mean ± SEM)] received a venous infusion of insulin (30 – 40 mIU m−2 min−1) for 120 min while glucose was maintained at euglycemic concentrations throughout via a variable 20% dextrose infusion. Plasma glucose was determined every 5 min to adjust the dextrose infusion. In addition, every 30 min blood samples were taken and stored for later determination of insulin and glucose levels; and respiratory rate was determined from the abdominal movements detected with a strain‐gauge pneumobelt. As expected, insulin concentrations were elevated and maintained throughout the clamp (Baseline: 5 ± 1 μIU mL−1, Clamp at 120 min: 42 ± 5 μIU mL−1; P < 0.01), while glucose remained at fasting values (Baseline: 89 ± 2 mg dL−1, Clamp at 120 min: 83 ± 2 mg dL−1; P = 0.15). Respiration rate increased at 30 min following insulin infusion (Baseline: 13.8 ± 0.7 breaths min−1, Clamp at 30 min: 14.9 ± 0.7 breaths min−1; P < 0.01) and this elevation was maintained throughout the clamp reaching a peak value of 15.9 ± 0.6 breaths min−1 (P < 0.01). In a subset of subjects, respiration rate remained unchanged during saline infusion (Baseline: 14.3 ± 0.3 breaths min−1, Clamp at 120 min: 14.9 ± 0.2 breaths min−1; P = 0.41). These preliminary findings suggest an excitatory effect of insulin to increase respiratory rate in healthy humans.Support or Funding InformationFunding Source: AHA Grant In Aid 20160072
Orexin A receptor 1 (OX1R) activation increases CamK2 expression in PC12 cells
Authors: Fan Yuanyuan , Jiang Enshe , Chen Qinchui , Shan Zhiying 
Published: November 2023

Previous study have demonstrated that orexin receptor activation resulted in an increase in sympathetic activity and elevation in intracellular calcium levels. This observation coupled with the important role of calcium on the control of Ca2+/calmodulin‐dependent protein kinase II (CamK2) activity have led us to hypothesize that orexin system may involve in increasing sympathetic nerve activity through stimulating the expression of CamK2. In this study, we test this hypothesis using the neuron‐like PC12 cell which artificially expressing human orexin A receptor 1 (OX1R). Consistent with previous finding, incubation of human orexin A (100 nM) dramatically increased the cytosolic calcium level measured with a fluorescent calcium probe (Fluo‐4AM) in PC12‐OX1R cells. In addition, orexin A treatment (100nM) for 6 hours resulted in significant increases in the mRNA levels of calcium dependent protein early growth response 1 (EGR1, 25‐fold, P<0.05), CamK2a (2‐fold, P<0.05), CamK2b (4‐fold, P<0.05) as well as Fosl1 (9‐fold, P<0.05), a chronic neuronal activation marker, compared to control group. These data suggest that binding of orexin A and OX1R increases calcium influx which may subsequently stimulates EGR1 expression, the EGR1, as a major transcription regulator, may modulate expression of many genes including the expression of CamK2, which eventually increase neural firing. Our further study will investigate whether or not blockage of CamK2 will attenuate the increase in sympathetic nerve activity.Support or Funding InformationNIH R15HL129213 (Shan)
Slicing Orexin Receptor 1 in Paraventricular Nucleus Decreased Hypertension in Obesity Zucker Rats
Authors: Zhou Jing‐Jing , Zhang Yi , Li De‐Pei 
Published: November 2023

Orexin has been reported to involve in pathogenesis of obesity‐related hypertension. We found recently that that upregulation of orexin receptor 1 (OXR1) contributed to sympathetic overflow through excitation of presympathetic neurons in paraventricular nucleus of hypothalamus. The present study aimed to slicing OXR1 in PVN of Obese Zucker Rats (OZRs) to normalize the hypertensive status in OZRs. Blood pressure was monitored in free‐moving OZRs through implantable telemetry system. AAV‐OXR1‐shRNA and scrambled shRNA were constructed and bilaterally microinjected into the PVN. AAV‐OXR1‐shRNA significantly downregulation expression levels of OXR1 in the PVN tissue in OZRs, whereas orexin receptor 2 (OXR2) expression levels were not significantly changed. In addition, the retrograde labeled spinally projecting PVN neurons displayed significantly reduced OX1R immunostaining signals. The mean arterial blood pressure decreased by AAV‐OXR1‐shRNA treatment for 4–6 weeks, which companied with a lowered heart rate (HR). Spectral analysis of pulse‐pulse intervals revealed that low frequency to high frequency (LF/HF) ratio was significantly decreased. Furthermore, slicing OXR1 in PVN by AAV‐OXR1‐shRNA eliminated orexin‐induced increases in blood pressure and sympathetic activity in OZRs. In addition, the hyperactivity of spinally projecting PVN neurons in the OZRs was significantly decreased by AAV‐OXR1‐shRNA treatment. Taking together, these findings suggest that slicing OXR1 in PVN effectively normalizes elevated sympathetic vasomotor tone in obesity‐related hypertension.Support or Funding InformationThis work was supported by the National Institutes of Health (Grants MH096086 to D‐P. L.), National Natural Science Foundation of China (31271223 and 31071002), National Basic Research Development Program of China (2012CB518200), and the Natural Science Foundation of Hebei Province (C2012206001).
Effect of a Pre‐Dinner Snack on Buffet Meal Caloric Consumption in College Freshman
Authors: Schmitz Sophie A , Sebranek Phoebe L , Kern Shelby E , Hoppe Megan B , Scott Hattie J , Eastep Ashley C , Horwath Irina E , Wilson Ted 
Published: November 2023

Post adolescent weight gain is a concern among college freshman, especially those enrolled in cafeteria meal plans. Snack consumption prior to a meal could alter feeding behavior during the meal. Healthy college students (n=57; age 18.3±0.1) received one of three treatments 60 minute before choosing and eating a cafeteria dinner meal (no snack (NS; control), 190 Cal of gummi bear candy (GB), or a 190 Cal serving of California walnuts (CW) 60 minutes prior to dinner in single cross‐over fashion on 3 of 5 semi‐consecutive nights. Meal images before and after consumption were used for nutritional analysis and the determination of the calories that were consumed and unconsumed (left over on tray) at the end of the meal. This study highlights the complex interaction between pre‐dinner snack choice and food consumption during a meal in a homogeneous college population. Understanding how nut consumption influences this feeding pattern could help clinicians improve dietary health.Support or Funding InformationCalifornia Walnut Commission
The effects of acetate on enhancing the proliferation and preadipocyte differentiation of stromal vascular cells isolated from Hanwoo beef cattle
Authors: Baatar Delgerzul , Wandita Theresia Galuh , dela Cruz Joseph Flores , Hwang Seong Gu 
Published: November 2023

We investigated the effect of acetate on the proliferation and differentiation of bovine stromal‐vascular cells (SVC). SVC was isolated from the longissimus muscle collected directly from approximately 30‐month‐old Hanwoo beef cattle steers. After confluence, the differentiation was induced by 1‐methyl‐3‐isobutyl‐xanthine, dexamethasone, insulin, and rosiglitaszone for 2 days, and then subsequently cultured for 14 days. The cells were treated with different concentrations of acetate (0.125 to 2 mMol) throughout the differentiation period. Cell viability assay revealed a dose‐dependent increase in the proliferation of SVC. Monitoring of the differentiation through Oil Red‐O staining showed that treatment with acetate up to 1mMol significantly increased cell differentiation and fat accumulation. Supplementation of acetate in the media throughout the differentiation period also enhanced the induction of all differentiation markers. Acetate treatment unregulated the mRNA and protein expression of peroxisome proliferator‐activated receptor gamma (PPARγ), CCAAT/enhancer binding protein alpha (C/EBPα), Sterol regulatory element‐binding protein 1c (SREBP‐1c), fatty acid binding protein 4 (FABP 4) and fatty acid synthase (FAS). These data suggests that acetate can enhance adipocyte differentiation from SVC isolated from Hanwoo beef cattle and possibly improve meat palatability through increased intramuscular fat deposition and reduce meat toughness through decreased fibrogenic differentiation.Support or Funding InformationThis work was carried out by the support of the Rural Development Administration Grant (Project No. PJ01268703).
Evaluation of Patient‐Specific MTERF4 Variants in Gene‐Edited Human iPSC‐derived Cardiomyocytes
Authors: Marquez Maribel , McDermott‐Roe Chris , Grysbowski Michael , Helbling Daniel , Dimmock David P. , Verbsky James W. , Geurts Aron M 
Published: November 2023

Mitochondrial Transcription Termination Factor 4 (MTERF4) has been well established as a transcription factor for mitochondrial ribosomal biogenesis and was identified as a gene of interest via exome sequencing in a male 6‐year‐old patient with hypertrophic cardiomyopathy (HCM) at Children's Hospital of Wisconsin. This patient's specific variant in MTERF4 has not been previously reported in the literature or associated to HCM. An existing mouse model by Cámara et al. has shown that a global knock out (KO) of MTERF4 resulted in embryonic lethality at developmental stage E8.5 and that a heart‐specific conditional KO resulted in an enlarged heart. Our lab has combined precision genome editing via CRISPR/Cas9 system with human iPSC‐derived cardiomyocytes (CMs) to model this patient‐specific MTERF4 variant to determine if it is responsible, or contributes to, the patient's HCM phenotype. Due to low homology‐directed repair (HDR) events in human iPSCs, we employed a novel co‐targeting selection method that enhances targeting efficiency. Based on the previously published literature of MTERF4 knock outs, we hypothesize that our MTERF4 mutant clones, once differentiated into cardiomyocytes, will be larger in size and have an increased transcriptional expression of HCM markers as well as an increase in mitochondrial transcript and protein expression. Three mutant MTERF4 clones have been identified by sanger sequencing, were assessed for pluripotency using immunostaining for SSEA‐4 and Oct4, and QPCR was done using Oct4, GATA4, and SOX2 primers. Human iPSCs that have undergone our targeting protocol and were negative for the MTERF4 variant will serve as controls for the MTERF4 mutant clones. MTERF4 clones and controls will be subjected to our modified Palecek matrix‐overlay method for cardiomyocyte differentiation, at 3–4 weeks CMs will be assessed for cell size using immunostaining for Cardiac Troponin T, the transcriptional expression will be done via QPCR, and mitochondrial protein expression assessed by western blot. Future mechanistic studies will be driven by the correlation between MTERF4 variant and HCM.Support or Funding InformationKeck foundation and NIH Director's New Innovator award (DP2‐OD08396)