bluuebunny/crossref_metadata_2025 huggingface dataset:
Muscle Glycogen Content and the eEF2 Response to Resistance Exercise in Young and Old Subjects
Authors: SHI Rengfei , Macesich Jennifer L. , Harper Bradley M. , Tharrington India H. , Gavin Timothy P. , Heidal Kimberly , Hickner Robert C. , Farrell Peter A. , Pofahl Walter E. , Gordon Scott E.
Published: June 2021

We examined the relationship between glycogen content, AMP‐activated protein kinase (AMPK), and eukaryotic elongation factor 2 (eEF2) in response to resistance exercise in young and old skeletal muscle. Seven young (21.7 ± 2.1 yrs) and 11 old (67.0 ± 8.6 yrs) men and women performed an acute bout of leg extension exercise. Muscle biopsies were obtained pre‐ (PRE), immediately post‐ (0P), 1‐hr post‐ (1P), and 2‐hr post‐exercise (2P). Glycogen content was measured in muscle samples, as were the phosphorylations (via western blot) of AMPK, acetyl‐CoA carboxylase (ACC; a marker of AMPK activity), and eEF2. AMPK phosphorylation was significantly increased vs. PRE in old, but not young, subjects at 0P. However, no age‐related differences were observed in AMPK activity, which was significantly elevated at 0P and 1P in both age groups. Similarly, inhibitory eEF2 phosphorylation (elevated at 0P and decreased at 1P and 2P vs. PRE in both age groups) was also unaffected by age. Regardless of age, higher muscle glycogen content was associated with lower AMPK activity at 0P and 1P, and this lower AMPK activity was associated with lower inhibitory phosphorylation of eEF2 at those same timepoints. Thus, higher muscle glycogen content may result in lower AMPK activation and consequently lower inhibitory eEF2 phosphorylation in response to resistance exercise in the muscles of both younger and older individuals.
Low‐Intensity Exercise Training Prevents Muscular Microangiopathy in Non‐obese Type 2 Diabetic Rats
Authors: Fujino Hidemi , Kondo Hiroyo , Murakami Sinichiro , Fujita Naoto , Morifuji Takeshi , Nagatomo Fumiko , Ishihara Akihiko
Published: June 2021

PURPOSE

The purpose of the present study was to investigate the effects of low‐intensity exercise training on the angiopathy of skeletal muscle by type 2 diabetes.

METHODS

Male Goto‐Kakizaki (GK) non‐obese type 2 diabetic rats (6 weeks old) and wild‐type Wistar rats (Con) were used. GK rats divided into 2 groups: diabetes (GK) and diabetes plus low‐intensity exercise training (GK+Ex). The low‐intensity exercise training was conducted during 60 min, 5 times per week, for 3 weeks. The three‐dimensional capillary network of soleus muscle was visualized using a confocal laser microscopy. The mRNA expression levels of angiogenic factors (VEGF, KDR, Flt‐1, Ang‐1, Ang‐2, Tie‐2, and HIF‐1 alpha) in the soleus muscle were determined by TaqMan probe‐based real‐time PCR.

RESULTS

The capillary volume in the muscle was lower in GK than in Con rats. However, the capillary volume in the muscle of GK+Ex was increased toward to the level of Con rats. Although the expression levels of angiogenic factors in the muscle were lower in GK than in Con, those were increased toward to the levels of those in GK+Ex rats.

CONCLUSION

The present results provide evidence of the effectiveness of endurance exercise training that reduces the muscle circulatory complications associated with type 2 diabetes. Supported by Grants‐in‐Aid for Science Research from the Japanese Ministry of Education, Culture, Sports, Science and Technology, no. 22300189.
Testosterone lowers microvascular ET‐B receptor responsiveness in women with PCOS
Authors: Wenner Megan M , Taylor Hugh S , Stachenfeld Nina S
Published: June 2021

High testosterone (T) exposure is a characteristic of polycystic ovary syndrome (PCOS). T is also associated with greater ET‐1 plasma concentration, which may contribute to vascular dysfunction in women with PCOS. To test the hypothesis that T‐related impaired microvascular function associated with PCOS is mediated by ET‐B receptors, we suppressed endogenous sex hormones in 4 Control (23±2 years, 35.2±1.3kg/m2) and 4 women with PCOS (22±1 years, 36.2±2.5kg/m2) using a GnRH antagonist (GnRHa, 9 days); we then administered T (2.5 mg/day, oral) the last 4 days of GnRHa. We measured cutaneous vascular conductance (CVC) responses to local heating with laser Doppler flowmetry during microdialysis infusions of saline, ET‐A (BQ‐123), and ET‐B (BQ‐788) receptor antagonists. Baseline CVC was similar during GnRHa in Control (0.096±0.061 AU/mmHg) and PCOS (0.102±0.010 AU/mmHg). T administration tended to increase baseline CVC in Control (0.213±0.106 AU/mmHg; P=0.09) but not PCOS (0.082±0.018 AU/mmHg). Heat‐induced vasodilation during saline was similar between Control and PCOS. However, T administration attenuated heat‐induced vasodilation during ET‐B antagonism in Control (Δ GnRHa 1.13±0.14, T 0.43±0.12 AU/mmHg; P<0.01) but not PCOS (Δ GnRHa 1.38±0.32, T 1.06±0.34 AU/mmHg). ET‐A antagonism had minimal effect in either group. Women with PCOS show blunted ET‐B receptor sensitivity during T exposure. HL093450
Dynamic changes in cardiovascular function during diving and decompression at different core temperatures
Authors: Gaustad Svein Erik , Kondratiev Timofei , Haaheim Brage , Møllerløkken Andreas , Sieck Gary , Wisløff Ulrik , Brubakk Alf , Tveita Torkjel
Published: June 2021

Diving under cold conditions may add an additional risk for bubble production and decompression sickness. Additionally, there is sparse information regarding hemodynamic changes occurring during a dive and its effects on the outcome of a dive. Thus, detailed recordings of cardiovascular changes at different core temperatures during diving were studied. Anesthetized rats were monitored with a pressure‐volume catheter in the left ventricle and the femoral artery. Rats were randomly assigned to be normothermic controls, to perform a dry hyberbaric dive at constant core temperature (37ºC) or a dry hyperbaric dive with a core temperature of 35ºC during decompression and the early post dive period. The rats were compressed to 600 kPa, maintained for 45 min breathing air, and decompressed linearly to the surface at a rate of 50 kPa·min−1. Immediately after surfacing, right ventricle and pulmonary artery were insonated for bubble detection using ultrasound. Compression increased mean arterial pressure, pulse pressure, stroke volume, cardiac output, LV end‐systolic volume, LV end‐systolic pressure, LV dp/dt max, and total peripheral resistance in the rats. Most of these changes gradually declined and returned to baseline after decompression. However, rewarming to 37ºC after a 2ºC drop in core temperature caused a significant reduction in SV and CO, but this did not have an effect on bubble production and survival.
Role of reactive oxygen species in the neural and hormonal regulation of the PNMT gene in PC12 cells
Authors: Crispo James , Ansell Dominique , Ubriaco Gino , Tai T.C.
Published: June 2021

In adrenergic cells norepinephrine is N‐methylated by the enzyme phenylethanolamine N‐methyltransferase (PNMT) to produce epinephrine. Prior studies have demonstrated that the PNMT gene in adrenal chromaffin cells may be regulated hormonally via the hypothalamic‐pituitary‐adrenal axis and neurally via stimulation of the splanchnic nerve. Further, hypoxia has been shown to play a key role in the regulation of PNMT. The purpose of this study was to examine the impact of reactive oxygen species (ROS) produced by the hypoxia mimetic agent CoCl2 on the hormonal and neural stimulation of PNMT. RT‐PCR analyses show inductions of the PNMT intron‐retaining and intronless mRNA splice variants by CoCl2 (3.0‐ and 1.76‐fold respectively). Transient transfection assays of cells treated simultaneously with CoCl2 and dexamethasone show increased promoter activity (18.5‐fold), while mRNA levels of both splice variants do not demonstrate synergistic effects. Similar results were observed when investigating the effects of CoCl2‐induced ROS on the neural stimulation of PNMT. Our findings demonstrate that CoCl2‐induced ROS have synergistic effects on the hormonal and neural activation of the PNMT promoter and suggest post‐transcriptional regulation of PNMT following hormonal or neural activation during hypoxia. This study was funded by the Natural Sciences and Engineering Research Council of Canada.
Fiber‐specific expression of alpha‐actinin‐3 protein in rat diaphragm
Authors: Ichinoseki‐Sekine Noriko , Yoshihara Toshinori , Ogura Yuji , Sugiura Takao , Powers Scott K , Naito Hisashi
Published: June 2021

Alpha‐actinin‐3 is a major structural component of the Z‐lines in skeletal muscle that maintain the spatial relationship between myofilaments. However, fiber‐specific expression of alpha‐actinin‐3 vary among the species and different muscles. The purpose of this study was to examine the alpha‐actinin‐3 protein expression in rat diaphragm. Adult Wistar male rats (n=8) were anesthetized and the diaphragm were collected. Immunohistochemical detection of muscle fiber type (Type I, Type IIa and Type IId/x) and alpha‐actinin‐3 expression were performed. Percentage of cross‐sectional area (CSA) occupied by each fiber type were; Type I: 20.5%, Type IIa: 17.8%, and Type IId/x: 61.7%. Fiber CSAs were; Type I: 857.1 ± 58.9 μm2, Type IIa: 971.3 ± 41.9 μm2, and Type IId/x: 3529.0 ± 171.8 μm2. Alpha‐actinin‐3 was not expressed in Type I fiber same as previous reports in mouse and human. On the other hand, all of type IId/x fiber expressed alpha‐actinin‐3. We also observed expression of alpha‐actinin‐3 in 13.9 ± 8.9% of type IIa fibers. These observations indicated that expression pattern of alpha‐actinin‐3 in rat diaphragm was different from those of other species.
Nuclear apoptosis contributes to skeletal muscle cachexia in patients with rheumatoid arthritis
Authors: Sharif Salaheddin , Thomas James M , Donley David A , Gilleland Diana L , Bonner Daniel E , McCrory Jean L. , Hornsby W. Guyton , Hao Yanlei , Zhao Hua , Gutmann Laurie , Lively Mathew W , Hornsby Jo Ann A , Alway Stephen E
Published: June 2021

Rheumatoid arthritis (RA) is a chronic, systemic, autoimmune, inflammatory disease associated with cachexia (reduced muscle and increased fat). The purpose of this study was to determine if elevated apoptotic signaling occurred in skeletal muscles of RA patients. A needle muscle biopsy was obtained from the vastus lateralis of four RA subjects. Frozen tissue cross‐sections were evaluated for nuclear density (nuclei/μm2) and fiber cross‐sectional area. Mean muscle fiber area was 2384.1 ± 570.5 μm2, and the nuclear density was 6.8 nuclei/μm2. The number of nuclei with DNA strand breaks was determined by a fluorometric terminal deoxyribonucleotidyl transferase (TdT)‐mediated dUTP nick end labeling (TUNEL) assay. The number of TUNEL positive nuclei was 9.8 ±0.1% in vastus laterals biopsy samples. Western blot analysis and muscle morphology were consistent with the conclusion that rheumatoid cachexia is accompanied by a low level of apoptotic signaling in RA subjects.
The Effect of Acute High‐intensity Resistance Exercise and Dietary Cholesterol on PPARδ Protein Content in Skeletal Muscle
Authors: Chen Vincent C.W. , Lee Chang Woock , Lee Teak V , Bui Steve , Riechman Steven E
Published: June 2021

PPARδ expression in skeletal muscle has been shown to increase in response to endurance exercise training. However, the effect of acute high‐intensity resistance exercise (RE) and/or dietary cholesterol (CL) intake on PPARδ expression has not been investigated in humans and is thus the purpose of this study. Fourteen untrained, healthy young men and women were randomly assigned to a high‐cholesterol (HC: 14mg/kg lean/day, n=8) or low‐cholesterol intake group (LC: 3.5mg/kg lean/day, n=6), and instructed to perform 2 bouts of eccentric RE consisting of unilateral leg presses and extensions to fatigue. Muscle biopsies were performed on both exercise (EX) and non‐exercise (NoEX) legs 22 hours after exercise. PPARδ levels were analyzed via Western Blotting. The results showed no significant difference in PPARδ levels between HC and LC groups (p=0.868) or EX and NoEX legs (p=0.325). However, there was a significant interaction between RE and CL intake in PPARδ levels (p=0.047). In HC group, PPARδ levels in EX legs (1.81±0.44 AU) were higher than NoEX legs (1.04±0.15 AU) by 74% (p=0.029) while exercise had no effect on PPARδ levels in LC group (EX: 1.36±0.31 AU, NoEX: 1.64±0.44 AU, p=0.445). Our data suggest that when combined with high CL intake, acute high‐intensity RE may enhance PPARδ expression while acute high‐intensity RE or dietary CL alone has no effect on PPARδ levels.
Effects of Exercise Preconditioning on Capillary in Soleus Muscle of Type 2 Diabetic Rats
Authors: Murakami Shinichiro , Morifuji Takeshi , Kondo Hiroyo , Takeda Isao , Fujita Naoto , Fujino Hidemi
Published: June 2021

Type 2 diabetes mellitus is tightly linked to impaired skeletalmuscle glucose uptake and storage. The 3‐D capillarity, myosin heavy chain isoforms (MyHC) transformation and succinatedehydrogenase (SDH) activity in the soleus muscle were different between diabetic and non‐diabetic rats. Aerobic exercise has been known an effective therapy against the diabetes.

PURPOSE

To clarify the effect of aerobic exercise on capillary architecture in diabetic muscle, the 3‐D capillarity has been investigated.

METHODS

Goto‐Kakizaki (GK) (36weeks old, n=6) rats, a spontaneous non‐obese type2 diabetes model, and age matched GK rat that performed aerobic exercise preconditioning for 2weeks (GK‐EX), (n=6) were used. The contrast medium‐injected capillaryin the soleus muscle was visualizedusing a confocal laser microscope. The SDH activity and MyHC type were measured.

RESULTS

The soleus muscles in GK and GK‐EX were composed of only type I MyHC. The SDH activity in GK‐EX was significantly higher than that in GK. The capillary diameter in the soleus of GK‐EX rat wassmaller than that of GK rat. And the mean capillary volumein GK‐EX was significantly higher than that in GK.

CONCLUSION

The results of the present study indicate that aerobic training improves impaired capillarity in diabetic muscle. This studywas supported by Grants‐in‐Aid for Scientific Research from the Japanese Ministry of Education, Culture,Sports, Science and Technology no. 21700559 and 22300189.
Resveratrol affects inflammation and muscle function in mdx mice
Authors: Kostek Matthew C , Gordon Bradley S , Diaz Diana Carolina Delgado
Published: June 2021

Duchenne Muscular Dystrophy (DMD) is a genetic disease characterized by chronic inflammation and muscle degeneration/regeneration. Resveratrol is a compound that has anti inflammatory properties. However its effect on inflammation and muscle function in DMD is unknown. The purpose of this study was to investigate the effect of resveratrol on inflammation and muscle function in the mdx mouse model of DMD. A ten day dosage trial and an eight week treatment trial were performed. Ten days of resveratrol supplementation (100mg/kg) significantly increased Sirt1 gene expression 1.57 ± 0.11 fold (p<0.01), IL‐6 gene expression 3.52 ± 0.023 fold (p<0.05), and did not affect TNF alpha gene expression in the gastrocnemius. This dose increased tibialis anterior H2O2 content 80.6% (p<0.05). Eight weeks of resveratrol supplementation (100 mg/kg) increased peak tension of the tricep surae muscle complex by 9.5% (p<0.05). There was no effect on time to peak tension or muscle fatigue. Our data suggests a positive effect of resveratrol on inflammation and muscle function in the mdx mouse. This project was funded by The Center for Alternative Medicine at The University of South Carolina School of Medicine.
Study of coronary artery origin anomalies using CT angiography
Authors: Zahoi Delia Elena , Daescu Ecaterina , Miclaus Gratian , Enache Alexandra , Ureche Mioara Farca
Published: June 2021

The anatomy of the coronaries presents great variability, as confirmed by the anatomists' interest in elucidating the coronary circulation. CT angiography is a method that allows the evaluation of the vascular anatomy and the diagnosis of vascular diseases. The images were obtained with a Somatom Siemens 64 angiograph. The incidence of the origin variants of the coronaries in the studied material was 1.6%. In accordance with the literature, these anomalies were grouped in 2 categories: anomalies of coronary sinus origin and anomalies of ectopic origin. The following varieties were revealed in the first category: left coronary artery originating in the right coronary sinus; left coronary artery arising from a common trunk with the right coronary; circumflex artery originating in the right coronary artery and left coronary artery arising from the posterior part of the aorta. In one case, the ectopic origin of the left coronary artery was the pulmonary artery. About 20% of the coronary artery anomalies cause symptoms such as arrhythmia, syncopes, myocardial infarction or sudden cardiac death. Early identification of an anomalous coronary anatomy is relevant because of the increased incidence of sudden cardiac death. CT angiography plays an increasingly important role in the diagnosis of coronary artery anomalies, as it is a non‐invasive method that provides detailed three‐dimensional anatomical data.
The effects of different oxidative and sulfhydryl agents on a novel, non‐AT1, non‐AT2 angiotensin binding site
Authors: Santos Kira L , Speth Robert C
Published: June 2021

A novel non‐AT1, non‐AT2 binding site for angiotensin peptides unmasked by p‐chloromercuribenzoate (PCMB) has been discovered in brain. The ability of different oxidative and sulfhydryl reactive agents to unmask or inhibit 125I‐Sar1Ile8 angiotensin (SI‐Ang II) binding to this site was examined. In membranes from homogenates of brain and testis incubated in assay buffer containing losartan (10 μM) and PD123319 (10 μM) plus 100 μM PCMB, 4 of the 25 compounds tested inhibited 125I‐SI Ang II binding in brain and testis. HgCl2 was the most potent inhibitor IC50 = 17 and 11 μM in brain and testis, respectively. Reduced GSH inhibited 125I‐SI Ang II binding in brain and testis with IC50 values of 224 and 420 μM, respectively. Oxidized glutathione (up to 1 mM) did not inhibit 125I‐SI Ang II binding. Thimerosal and 4‐OH‐mercuribenzoate also inhibited 125I‐SI Ang II binding in brain and testis at 100 μM, however they also unmasked non‐AT1, non‐AT2 125I‐SI Ang II binding in a concentration‐dependent manner in the absence of PCMB as if they were acting as partial agonists. The presence of mercury appears to be critical for unmasking the binding site. Addition of 4‐OH benzoic acid did not cause 125I‐SI Ang II binding to this binding site. These results suggest that modification of cysteine residues on this protein must be highly specific to cause the conformational change that enables the protein to bind Ang II. Supported by NHLBI HL‐ 096357.
Substance P (SP) Contributes To Rapidly Adapting Receptor (RAR) Activity In High Altitude Pulmonary Edema (HAPE)
Authors: Bhagat Ruchi , Yasir A , Vashisht A , Ravi K
Published: June 2021

Aims

To investigate whether there is a change in i) basal RAR activity and ii) their responses to SP, in rabbits with HAPE.

Methods

Experiments were performed in anesthetized, artificially ventilated and thoracotomized rabbits. After routine cannulations, the RAR activity was recorded from cervical vagus nerve. Increasing doses of SP were administered into the right atrium in control rabbits (C) breathing room air (n= 6) and in rabbits with HAPE (n= 6). To produce HAPE, rabbits were placed in a high altitude simulation chamber ‐ 15,000 feet, 36 hrs. In both the groups, SP doses were repeated after the administration of NK‐1 receptor antagonist, CP‐96345 (400 nmol/kg, Pfizer, Croton, USA).

Results

The basal RAR activity in C was 6.34±0.46 impulses/breath and it increased to 10.0±0.64 impulses/breath (p<0.001) in HAPE. SP stimulated the RARs in both the groups. However, in HAPE, the RARs were stimulated even by sub‐threshold doses of SP. CP‐96345 attenuated the RAR activity in C but not in HAPE.

RAR response to SP in C and HAPE groups.

RAR activity in %

Groups
After SP (μg/kg)

0.02
0.04
0.08

Before CP‐96345
C
16.22±4.99
28.44±7.00
48.95±9.92

HAPE
51.14±5.10 ***
54.83±3.77**
Not done

After CP‐96345
C
18.10±8.59
24.44±9.27
20.58±4.98

HAPE
38.55±8.87
56.50±6.11*
Not done

RAR activity expressed as a percentage of their respective basal activities.

p<0.05,

p<0.01 and

p<0.001, compared with the corresponding response in C.

Conclusion

1.HAPE stimulates RARs. 2. The RARs do not show adaptation to this stimulus. 3. Endogenous SP released during HAPE sensitizes the RARs to exogenous SP. Funded by DIPAS, Delhi.
Hypoglossal motoneuron pathology in a mouse model of Pompe disease
Authors: Sandhu Milap S , Lee Kun‐Ze , Elmallah Mai K , Falk Darin J , Mattio Rachel Y , Gonzalez‐Rothi Elisa , Reier Paul J , Byrne Barry J , Fuller David D
Published: June 2021

Pompe disease is a lysosomal storage disorder associated with acid α‐glucosidase (GAA) deficiency. Both diaphragm and upper airway muscle dysfunction occur in Pompe disease and this may reflect central nervous system (CNS) pathology. We used a murine model of Pompe disease to test the hypothesis that systemic GAA deficiency is associated with hypoglossal (XII) motoneuron pathology and altered XII motor output. Brainstem tissue was harvested from adult Gaa−/− mice and the periodic acid Schiff (PAS) method was used to examine neuronal glycogen accumulation. Semi‐thin (2 μm) plastic sections showed extensive cytoplasmic glycogen accumulation in XII motoneuron soma. Phrenic and XII bursting was recorded in anesthetized and ventilated Gaa−/−and B6/129 mice before and after bilateral vagotomy. Vagotomy caused a robust increase in XII inspiratory burst amplitude in B6/129 mice (238 ± 44 %baseline; P < 0.01) but had little impact on burst amplitude in Gaa−/−mice (130 ± 23 %baseline; P > 0.05). Regression analysis revealed that phrenic and XII burst amplitudes were significantly correlated in B6/129 (r2 = 0.27, P < 0.05) but not Gaa−/−mice (r2 = 0.08, P = 0.27). This finding may indicate that the progression of neuropathology differs between XII and phrenic motoneurons in Gaa−/−mice. We conclude that CNS GAA deficiency is associated with glycogen accumulation in XII motoneuron cell bodies and altered XII motor output.
Endothelial‐specific Gαq/11 deficiency prevents LPS‐induced lung injury
Authors: Garcia Alexander Nathaniel , Komarova Yulia , Gao Xiao‐Pei , Vogel Stephen M , Malik Asrar B.
Published: June 2021

Lipopolysaccharide (LPS), a product of gram‐negative bacilli, exerts its effect on the endothelium by inducing Toll‐like receptor 4 (TLR‐4)‐mediated release of pro‐inflammatory mediators, including barrier disruptive agents such as histamine and platelet activating factor (PAF) from dendritic cells and monocytes, as well as leading to generation of thrombin in fibrin clots. Many of these mediators signal through G‐protein coupled receptors (GPCR), which directly activate the Gαq/11 family of heterotrimeric G proteins. We propose that G αq/11 –mediated signaling in the endothelium plays a critical role in the development of pulmonary edema in the context of inflammation. To address this hypothesis we utilized mice with endothelial‐specific Gαq/Gα11 deficiency for an LPS inhalation model of lung inflammation and injury. Lungs isolated from control group demonstrated two fold increase in capillary filtration coefficient (Kf,c) value, a measure of vessel permeability, at five hours after LPS inhalation. Gαq/Gα11 deficiency significantly inhibited the increased permeability of lung vessels, suggesting that endothelial‐specific events downstream of Gαq/Gα11 activation play a critical role in the mechanism of lung edema and injury. In the future study we will determine whether Gαq/Gα11 signaling acts via PLCβ to induce acto‐myosin contractility and cell shape change in endothelial cells.
GABAergic mechanisms underlying episodic breathing in rat brainstem‐spinal cord preparations
Authors: Scheib Rachel , Fong Angelina , Milsom William K , Zimmer M Beth
Published: June 2021

Using neonatal rat brainstem‐spinal cord preparations, we examined respiratory activity to characterize the production of episodic breathing patterns with the pons intact and the pons removed; and in the presence of GABA receptor agonists and antagonists. Neonatal rats (P0‐P4) were anesthetized and brainstem spinal cords removed. Respiratory‐like activity from C1 and C4 ventral roots were recorded (21–23C) and raw recordings were integrated and analyzed for respiratory burst duration, peak height, peak area, frequency and breathing pattern (episodic vs. continuous) before and after GABA receptor activation or blockade. Episodic patterns were expressed in a high percentage of young preparations at room temperature. With the pons intact, the GABAA antagonist, bicuculline, increased burst frequency and burst duration. The increase in duration appeared to be due to the combination of two or three distinct bursts with no expiratory pauses, suggesting the appearance of episodic pattern formation. With the pons removed, bicuculline increased burst frequency but had no effect on duration. GABAA receptor agonists (muscimol and chlorpromazine) decreased frequency and turned episodic patterns to continuous patterns. Phaclofen, a GABAB receptor antagonist, had no effect on respiratory pattern or frequency. These results show that GABAA but not GABAB receptors play a role in episodic respiratory pattern generation and that pontine mechanisms are involved in this pathway.
Real‐time fluorescence microscopy reveals ICAM‐1‐dependent leukocyte margination in microvessels of LPS‐treated lungs
Authors: Kandasamy Kathirvel , Sahu Geetaram , Parthasarathi Kaushik
Published: June 2021

Increased leukocyte migration from lung vessels into airspaces is a hallmark of sepsis. However, specific migration sites and mechanisms remain unclear. Toward this, we prepared isolated blood‐perfused rat lungs and imaged surface vessels by real‐time fluorescence microscopy. Via a left atrial catheter, we infused Ringer's solution or LPS (100 μg/ml) for 30 min into microvessels. After 1hr we infused leukocytes (100000 cells/ml) labeled with Rhodamine 6G and imaged their transit through microvessels. Then we quantified the number of marginated leukocytes in microvessels in 5 distinct 62500 μm2 regions for each lung. Ringer's infusion resulted in margination of 9.2±0.8 (mean±SE, n=3) leukocytes. In contrast, LPS infusion doubled the number of marginated leukocytes to 21.5±3.7 (n=3; p<0.05). Margination increased in both capillaries and venules, suggesting that LPS increased leukocyte accumulation in both vessel segments. To define mechanisms, we infused an ICAM‐1 antibody into LPS‐treated microvessels prior to leukocyte infusion. The antibody blunted the LPS response to control levels (6.5±0.5; n=3) in both venules and capillaries, indicating that ICAM‐1 mediates LPS‐induced leukocyte margination in these microvessels. We interpret that in lung, LPS increases ICAM‐1 expression in capillaries and venules; and both microvessel segments may be sites of leukocyte migration during sepsis. (NIH HL75503)
Surgical model for functional intravital microscopy of the lung using an acute window
Authors: Hanna Gabi , Palmer Gregory , Shan Siqing , Radiloff Daniel , Dewhirst Mark , McMahon Timothy , Irwin David , Schroeder Thies
Published: June 2021

Introduction

Numerous pathologies of the lung could benefit from a model of functional microscopic imaging of the lung in laboratory animals. Recent developments in window chamber microscopy enable us to measure key parameters of the lung including capillary blood flow and hemoglobin saturation. Functional intravital microscopy at high magnification, however, requires a still image for extended exposure times which is very difficult to obtain in the lung due to respiratory and cardiac movement.

Methods

Female Sprague Dawley rats were anesthetized with ketamine/xylazine, tracheotomized, connected to a ventilator and subjected to open‐chest surgery. A customized window was protruded into the surgical opening and sutured to the outside of the wound sealing the chest cavity resulting in direct contact to the lung. Vital signs were assessed using MouseOx. Imaging was done using a fluorescence Zeiss microscope at 100 x magnification. Image analysis was done using Matlab and Image J.

Results

We were able to eliminate lateral movement of the lung due to respiration and heart beat, and observe blood flow in vivo over a period of >1 min. We were able to measure hemoglobin saturation in pulmonary capillaries

Conclusions

Our surgical model enables intravital microscopy of the lung over extended imaging times. This model has clear potential to serve as a standard platform to study pathophysiologies of the lung.
Interaction between soluble guanylyl cyclase (sGC) and protein disulfide isomerase (PDI) in smooth muscle cells
Authors: Heckler Erin , Baskaran Padmamalini , Beuve Annie
Published: June 2021

Soluble guanylyl cyclase (sGC) is a nitric oxide (NO) sensor in the cardiovascular system. This heterodimeric enzyme contains a heme cofactor and converts guanosine triphosphate (GTP) to the signaling molecule, cyclic guanosine monophosphate (cGMP). Upon NO binding to the heme, production of cGMP is stimulated several hundred fold. We showed that sGC can be desensitized via S‐nitrosation (Sayed et al. PNAS 2007, 104, 12312‐17). More recently, Zheng et al implicate the reduction of key cysteine residues in sGC for enzyme activation (Zheng, et al. Cardiovascular Research published online Jan 19, 2011). This cytosolic enzyme has 34 cysteines, a thiol titer estimates that twelve of these are disulfide‐bonded, leaving a significant number of predicted free thiols in the native form of the enzyme. Previous work suggested that sGC associates with PDI (Balashova, et al. JBC 2005, 280, 2186‐2196; Sayed and Beuve unpublished observations). We show that this is a direct redox interaction involving key cysteines in sGC and PDI. The biological relevance of this interaction is under investigation.

Supported by NIH Grant R01 GM067640
Adhesion of transferrin to Tisifilcon A contact lenses
Authors: Solanki Darshan , Brinon Stephanie , Keith Edward O. , Janoff Andrea , Nishimura Sachiko
Published: June 2021

Tear proteins accumulate on contact lenses causing lens deterioration and conjunctival irritation. We examined the adhesion of transferrin to contact lenses made of tisifilcon A, a rigid gas‐permeable silicone hydrogel (FDA Group III). Lenses were incubated 2.0 mg/ml solutions of human holo‐transferrin for 1, 2, 3, and 4 days, and protein adhesion was determined by bicinchoninic acid assay. Transferrin adhesion increased from day 0 to day 3 and then dropped after days 4 and 5. This pattern resembled transferrin adhesion to lenses made of polymacon (FDA Group I), alphafilcon (FDA Group II), omafilcon (FDA Group II) and balafilcon (FDA Group III) materials, but differed from the pattern of transferrin adhesion to etafilcon (FDA Group IV) material. Transferrin adhesion to tisifilcon A was greater than transferrin adhesion to all other materials except balafilcon, which had equivalent transferrin adhesion. These differences may be related to the positive charges on transferrin originating from arginine residues and the N‐terminus. These cause transferrin to adhere better to the low water ionic Group III materials than to the non‐ionic materials (FDA Groups I and II) and the high water ionic material (FDA Group IV).

Supported by the Farquhar College of Arts and Sciences at NSU and the Menicon Company, Ltd.
A novel PAGE buffer for faster runs and sharper protein bands
Authors: Roemer Stephen , Sevigny Pierre , Modi Parul , Patil Shamee
Published: June 2021

Since the mid‐70s Laemmli's protocol based on a Tris‐glycine‐SDS buffer system has been widely used for analyzing protein mixtures by PAGE. Laemmli's buffer system allows clear and accurate molecular weight estimation of proteins in complex samples from a wide variety of sources, but at the cost of long electrophoresis time. Modifications and improvements of this method reducing total run‐time are limited to mainly high priced precast gels.

In this work, we demonstrate an improved Laemmli method offering significant cut in run‐time and improved sharpening of protein bands. The patent pending modifications apply to the running buffer system which can be run at higher voltages without generating high heat and impacting gel performance. We show that typical mini‐gels (10 x 10 cm gel) cast with the Laemmli recipe can be run 50 to 60% faster and still maintain a wide separation range similar to porosity gradient gels. In fact, a 10% Laemmli discontinuous mini‐gel will provide ultra‐fine band resolution over a wide molecular weight range (10 to 240 kDa) in less than 30 minutes using this unique running buffer. The need for gradient gels may be over since a uniform concentration gel can now fractionate proteins covering a wide range of molecular masses in half the time.
3D Slicer
Authors: Kikinis Ron
Published: June 2021

3D Slicer is:

A software platform for the analysis and visualization of bio‐medical images and for research in image guided therapy

An extensible algorithm and application development platform with a powerful plug‐in architecture

A free, open source package available on multiple operating systems (Windows, MAC, Linux) built on the NA‐MIC kit

The presentation will provide an overview of the available technologies and demonstrations of some of the capabilities of 3D Slicer.

This work is supported by NIH P41RR01328 and NIH U54EB005149.
Biophysical and Biochemical Characterization of Protein D/E: A Putative Glycoprotein Involved in Sperm/Egg Binding and Fusion
Authors: Copeland Clinton L. , Socolovsky Eduardo A , Ramesh Vani , Ramesh Govindarajan T , Hall Joseph C
Published: June 2021

The purpose of the present investigation was to develop a more efficient and rapid method for purifying protein D/E, also known as Cysteine‐rich secretory protein‐1 (CRISP‐1) from rat epididymal tissue. While there is ample experimental evidence in the literature which demonstrate the involvement of protein D/E in sperm/egg binding and/or membrane‐mediated fusion events, biophysical characterization and x‐ray crystallographic analysis of protein D/E has not been reported. Protein D/E was purified to apparent homogeneity, as assessed by one‐and‐two dimensional gel electrophoresis, in three conventional chromatographic steps, with a percent recovery of 0.5%. Preliminary biophysical characterization of protein D/E using circular dichroism spectroscopy suggests the presence of significant α‐helical content, suggesting that there may be functional binding motifs in the protein structure. Computer‐assisted drug design modeling of protein D/E structure was initiated using computational tools to identify potential structural binding motifs. Using the protein D/E amino acid sequence that was deduced from the gene sequence and computational model tools (Fugue and Biopolymer), potential protein binding motifs were identified on the protein surface. These data will be used to optimize egg/ligand interactions, synthesize and test ligands as potential inhibitors of sperm/egg binding and membrane‐mediated fusion events. [This study was supported, in part, by an NIH grant (P20 MS001822‐02) awarded to Dr. Joseph C. Hall, Director of the Center for Biotechnology and Biomedical Sciences and Vice President for Research and Economic Development, Norfolk State University, 700 Park Avenue, Norfolk, VA 23504]
Candy consumption in the United States
Authors: Shumow Laura , Barraj Leila M , Murphy Mary M , Bi Xiaoyu , Bodor Alison R
Published: June 2021

This study was conducted to better understand consumption of candy in the US. Using data reported in NHANES, candy intake was estimated as (1) the usual number of total candy eating occasions (EO) based on the combined daily frequency of chocolate and other candy intake over the previous 12 mo, and (2) the usual amount of candy consumed per day based on frequency of candy intake in combination with amounts consumed per EO. The mean frequency of candy intake was 0.38 EO/d, with 35.5% consuming candy infrequently (≤ 3 EO/mo), 37.1% consuming with moderate frequency (> 3 EO/mo and ≤ 3.5 EO/wk), and 27.4% with frequent intake (> 3.5 EO/wk). Usual intake of candy was estimated at 11.5 g/d at the mean and 4.8 g/d at the median; mean usual intakes of candy by tertile of consumption were 1.0, 5.3, and 28.1 g/d, respectively. There was no association between frequency of candy intake and amount per EO on days of chocolate or other candy consumption. Mean candy intake in NHANES 2003–06 was compared to intake in NHANES 2007–08 based on 1 day of recall; intake did not differ (37.7 ± 1.3 vs. 40.4 ± 1.9 g/d, p=0.24). Based on 2010 US sales and market data from The Futures Company, NPD and IRS, candy intake averaged 2 EO/wk. These estimates of candy consumption suggest that candy intake has remained relatively stable and provide insight into the role of candy in dietary patterns of the US population. Supported by the National Confectioners Association.
Heat‐processed Carcinogens: What Can We Learn from the “Coffee ‐ Cancer Paradox”?
Authors: Coughlin James R
Published: June 2021

Trace level animal carcinogens in heated foods, including acrylamide, furan, various aldehydes and 4‐methylimidazole, result from the Maillard Browning Reaction, and California's Proposition 65 law has targeted these carcinogens in coffee. While we must evaluate the toxicological risks of these individual carcinogens, it is equally important to fully evaluate the safety of whole foods containing them using modern clinical, toxicological, nutritional and epidemiological techniques. Currently there is little human epidemiologic evidence linking these trace level carcinogens with the risk of disease, including cancer. The health benefits of a food such as coffee, including numerous health‐protective compounds found naturally and those produced by heat, are often neglected by public health and regulatory authorities. In fact, coffee consumption has been shown to reduce the risk of several human cancers, in spite of the fact that coffee contains many animal carcinogens, a situation I call the Coffee ‐ Cancer Paradox. Therefore, it is critical to evaluate the beneficial health effects of heated foods/beverages and to undertake a thorough risk‐benefit evaluation of the whole food. For carcinogens, this evaluation must carefully consider how best to interpret animal cancer bioassays for individual chemicals, as well as epidemiological information that the whole food itself may actually be cancer protective.
Familial determinants of body mass index in Colombian 5–18 year old children
Authors: Casanova Ines Gonzalez , Stein Aryeh D. , Sarmiento Olga Lucia , Pratt Michael
Published: June 2021

Family socioeconomic status (SES), structure, and parental behaviors have been identified as important determinants of children's body mass index (BMI) in developed countries; however the role of these factors in other settings is not clear. We examined the role of family and household characteristics on BMI among 4,484 children 5 to 18 years measured in the 2005 Colombian Nutrition Survey 2005. We used 2‐ level hierarchical linear models with family as level 2, child as level 1, and BMI (continuous) as outcome. The family level explained 20% of variability in BMI. SES (difference 0.4 kg/m2in highest WI quintile vs. lowest), and caregiver education (0.02 kg/m2 per year of schooling) and overweight (0.5 kg/m2vs. normal) and obesity (1.3 kg/m2vs. normal) were positively associated with child BMI (all p<0.01). While living in an extended family was associated with 0.3 kg/m2increase in BMI, the number of family members was inversely associated with BMI (−0.1 kg/m2 per member). The association between parental weight status and child BMI is similar to that described in developed countries; however, the positive relationship between SES (WI and education) and BMI differs from developed country settings. This study identified important family and household predictors of BMI in Colombian children.
Functional analysis of liver and intestinal FABPs in the intestine: Comparison of LFABP and IFABP null mice
Authors: Gajda Angela Marie , Zhou Yin Xiu , Fortson Walter , Kodukula Sarala , Storch Judith
Published: June 2021

The fatty acid binding protein (FABP) family consists of ~15 kD cytosolic proteins which bind long chain fatty acids (FA) and other lipid species. Both liver‐type (LFABP; FABP1) and intestinal type (IFABP; FABP2) are present in the intestinal enterocyte, but the individual roles of these proteins are not known. These proteins bind long chain FA, but the LFABP binding site has a higher affinity for unsaturated than saturated FA. Hence, we examined the effects of dietary saturated vs. unsaturated FA in mice null for LFABP or IFABP. Male C57Bl6/J (WT), LFABP−/−, and IFABP−/− mice were fed isocaloric diets containing 10 kcal% fat (LFD), 45 kcal% fat rich in long chain saturated FA (HFS), or 45 kcal% unsaturated FA (HFU) for 12 weeks. The LFABP−/− mice fed the HFS diet had markedly higher body weights (BW) and fat mass (FM) relative to WT, while HFS diet feeding had the opposite effect on IFABP−/− mice. IFABP−/− mice fed HFU also had lower BW and FM. IFABP−/− mice also had higher respiratory exchange ratios relative to WT on both high fat diets, suggesting preferential utilization of carbohydrates as a fuel source. Thus, LFABP−/− and IFABP−/− mice display very different phenotypes in response to dietary lipids, suggesting that these proteins have discrete roles in enterocyte lipid metabolism and in whole body energy homeostasis.

Grant Funding Source: NIH DK38389 and NJAES
Development of a Whole‐body Model of Vitamin A Metabolism in Neonatal Rats Treated with Oil or Vitamin A and Retinoic Acid (VARA) Based on Compartmental Analysis of Retinol Tracer Kinetics
Authors: Tan Libo , Wray Amanda E. , Green Michael H. , Ross A. Catharine
Published: June 2021

Compartmental modeling has contributed greatly to our understanding of vitamin A (VA) metabolism in adult animals and humans. However, VA metabolism in neonates is virtually uncharacterized. Our objectives were to compare VARA supplementation vs. placebo oil on whole‐body retinol kinetics and to develop a whole‐body model of VA metabolism in neonatal rats, taking into account the inherent metabolic non‐steady state of neonates. On post‐natal day 4, rat pups (n=3/time point) received an oral dose of 11,12‐[3H]retinol admixed with oil or VARA. In pups treated with oil, radioactivity in plasma retinol rose quickly between 1 and 6 hours, with the absorption peak at 6 hr. Then there was a rapid disappearance of tracer, followed by a leveling off which reflects the recycling of retinol between plasma and extravascular tissues and a flat slope from 2 d to 8 d. Then radioactivity further declined into a terminal slope, which represents the initiation of retinol degradation. In pups treated with VARA, peak fraction of the oral dose in plasma was lower. VARA was also associated with a more rapid accumulation of radioactivity in liver and an increased fraction of the oral dose in lung. A compartmental model as viewed from the “plasma space” indicated extensive recycling of retinol between plasma and tissues in neonates, as in adults. Also, VARA stimulated the turnover of retinol between plasma and extravascular tissues.

NIH HD‐66982

Grant Funding Source : NIH
Association between erythrocyte n‐3 fatty acid levels and the risk of depression: case‐control study in Korea
Authors: Park Yongsoon
Published: June 2021

The purpose of the present study was to evaluate hypothesis that erythrocyte level of n‐3 PUFA and seafood intake were negatively associated with the risk of depression in Koreans. Eighty cases were consisted of patients diagnosed with depression Center for Epidemiological Studies Depression Scale Korea version (CES‐D‐K) score ¡Ã25 and confirmed by a psychiatrist according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Eighty eight controls were age‐and sex‐matched to the cases, and without a chronic disease. Multivariate‐adjusted regression analysis showed that the risk of depression was negatively associated with erythrocyte levels of 18:3n3, 20:5n3, 20:6n3, 16:0 and 18:0, but positively associated with erythrocyte level of 18:2t after adjusting for confounding factors. The risk of depression was also negatively associated with the intake of energy, carbohydrate, seafood and grains, but positively with the intake of fat and meat after adjusted for confounding factors including energy intake. Correlation analysis consistently showed similar results with CES‐D‐K score. In conclusion, high levels of n‐3 PUFA and saturated fatty acids, and intake of seafood and grain decreased, but level of trans‐fatty acid, and intake of fat and meat increased the risk of depression in this population. (This work was supported by the Korea Research Foundation Grant 2009‐0065576)
Urinary Excretion of 3‐Hydroxyisovaleryl Carnitine is Elevated in Lactating Women Consuming A Biotin Intake Exceeding Current Recommendations
Authors: Perry Cydne Aren , Gayle Antoinette , Malysheva Olga V. , Yan Jian , Caudill Marie A.
Published: June 2021

Urinary excretion of 3‐hydroxyisovaleryl carnitine (3HIA‐carnitine) is a functional biomarker of biotin status as it reflects impairment in leucine catabolism caused by reduced activity of the biotin‐dependent enzyme 3‐methylcrotonyl‐CoA carboxylase. As part of a 12‐wk controlled feeding study, healthy non‐pregnant (n=12), pregnant (n=13, 27wk gestation) and lactating (n=12, 5wk postpartum) women consumed 56 mcg biotin per day (~ 2x current adequate intake [AI] levels) as measured by LCMS. Twenty four hour urine collections were obtained and 3HIA‐carnitine was measured at wk 0 and 12 via LCMS. By study end, lactating women excreted two times more 3HIA‐carnitine compared to baseline (p=0.005) and 8 of 12 lactating women were excreting 3HIA‐carnitine above the upper limit of normal (i.e. > 0.2 mmol/mol creatnine). Urinary 3HIA‐carnitine excretion did not change in response to 56 mcg biotin per day among pregnant and nonpregnant women. These results indicate that lactating women may benefit from a biotin intake that exceeds the current AI of 35 mcg per day. Measurements of additional static and functional biomarkers of biotin status are underway to provide a more comprehensive assessment of the impact of physiologic state (i.e., lactation) on biotin status and requirements.

Funded and Supported by: The Gerber Foundation and The Hartwell Foundation.
Dietary folate and vitamin B6 intake insufficiencies among Cubans, Haitians and African‐Americans with type 2 diabetes
Authors: Ajabshir Sahar , Vaccaro Joan A. , Zarini Gustavo G. , Cheema Amanpreet K. , Huffman Fatma G.
Published: June 2021

Objective

To investigate dietary folate and vitamin B6 intake insufficiencies by ethnicity and diabetes status for three minorities.

Methods

A cohort of 865 participants [358 Cuban Americans (CA), 258 Haitian Americans (HA) and 249 African‐Americans (AA)] with diabetes (n=410) and without diabetes (n=455) was studied. Folate and vitamin B6 intakes were calculated from Willet's food frequency questionnaire.

Results

HA were more likely to have insufficient vitamin B6 intake than CA (OR=9.0, 95% CI 1.72– 47.6, P=0.009); whereas AA were more likely than HA to have insufficient vitamin B6 intake (OR=2.79, 95% CI 1.03–7.58, P=0.044). HA (OR=3.09, 95% CI 1.54– 6.21, P=0.002) as compared to CA were more likely to have insufficient folate intake. Also, individuals with diabetes (OR=1.79, 95% CI 1.13– 2.85, P=0.014) as compared to without diabetes were more likely to have insufficient folate intake.

Conclusion

AA and HA may be at risk for insufficient vitamin B6 and folate intakes. In addition, the results suggest that diabetes status may be a risk factor for insufficient intake of folate in these minorities.

Funding for this research was provided through and NIH/NIDDK sponsored grant.