bluuebunny/crossref_metadata_2025 huggingface dataset:
Physical training restores the increased pressor and chronotropic responses intensity‐induced by acute exercise in rats fed with hypercaloric diet
Authors: de Lima Daniel Carvalho , Guimarães Juliana Bohenen , Rodovalho Gisele Vieira , Silveira Simonton Andrade , Haibara Andrea Siqueira , Coimbra Cândido Celso
Published: June 2021

We have showed that hypercaloric diet induces an autonomic imbalance with reduced baroreflex sensitivity. The present study assessed the effect of exercise training on cardiac autonomic balance and cardiovascular adjustments induced by exercise in rats fed with hypercaloric diet. Male Wistar rats (weaning) were treated with hypercaloric diet (68%, Cho; 16%, Ptn) and submitted or not to exercise training in a treadmill (HD, n=10; HDT, n=9) during 9 weeks. Animals treated with chow diet (CD, n=11; 57% Cho; 30% Ptn) were used as control group. After training, we evaluate cardiac autonomic balance (methylatropine, 3 mg/Kg and propanolol, 4 mg/Kg) that showed an increased sympathetic tonus in HD (75%) and in HDT (104%). We also evaluated cardiovascular adjustments during submaximal exercise and we observed an increased pressor adjustment in HD that was attenuated by training (p<0.05). In adittion, the chronotropic adjustment was reduced in HDT (p<0.05). Midpoint, threshold pressure, saturation pressure and operating range were increased in HD by about 62%, 44%, 72% and 111%, respectively. However, maximal response of heart rate was attenuated in HDT (33%), as well as, threshold pressure (41%). In summary, exercise training improves the autonomic activity in response to exercise, restoring the increased cardiovascular responses in rats fed with hypercaloric diet. Financial support: CAPES, CNPq and FAPEMIG.
Glutamatergic transmission is altered in the caudal NTS of rats submitted to chronic intermittent hypoxia
Authors: da Costa Silva João Henrique , Zoccal Daniel Breseguello , Machado Benedito Honório
Published: June 2021

We hypothesize that chronic intermittent hypoxia (CIH) alters the glutamatergic mechanisms in neurons of the caudal aspect of nucleus of tractus solitarius (cNTS) of rats. Using in situ working heart‐brainstem preparations of rats submitted to CIH (6% O2, for 40 s every 9 min, 8 h/day; n=9) or normoxia (control, n=7) for 10 days, basal and chemoreflex‐induced changes in phrenic and sympathetic nerve activities were evaluated after microinjections of kynurenic acid (KYN, 250 mM) in the cNTS. KYN in the cNTS produced large increases in phrenic burst frequency (0.3±0.1 vs 0.8±0.1 Hz) and duration (0.6±0.1 vs 0.9±0.1 s) in control rats, while in CIH rats the increase in the frequency was smaller (0.3±0.1 vs 0.6±0.1 Hz) and no changes were observed in the duration (0.6±0.1 vs 0.7±0.1 sec). Besides, the sympathoexcitatory response to chemoreflex activation (KCN, 0.05%) was reduced in control rats (90±11 vs 56±6 %), but not in CIH rats (112±9 vs 119±10 %) after KYN in the cNTS, whilst no changes were observed in the tachypneic response in both groups. Accordingly, the expression of NMDAR1 in the cNTS, examined by immunoblotting, was higher in CIH (n=3) than in control rats (n=3)(p=0.02). Altogether, the data suggest that glutamatergic neurotransmission in the cNTS is increased after CIH exposure, which may contribute to the respiratory and sympathetic dysfunctions observed in this experimental model. Supported by FAPESP and CNPq.
Expression of c‐Fos protein in the nucleus of tractus solitary (NTS) and paraventricular nucleus of the hypothalamus (PVN) elicited by electrical stimulation of the aortic depressor nerve in conscious L‐NAME‐induced hypertensive rats
Authors: Pereira Ricardo M , Durand Marina T , Castania Jaci A , Oliveira Mauro , Salgado Maria Cristina O , Fazan Rubens , Salgado Helio C
Published: June 2021

To detect possible alterations of the baroreflex arch, we assessed the expression of c‐Fos in the NTS and PVN of L‐NAME‐induced hypertensive rats submitted to electrical stimulation of the aortic depressor nerve (ADN) in conscious state. Rats were treated for 14 days with L‐NAME (n=7), D‐NAME (n=5) or tap water (CONTROL; n=6). The animals were equipped with catheters in the femoral artery and vein, and a pair of electrodes for intermittent (5s on/10s off) electrical stimulation (1mA, 2ms and 60Hz) during 20 min. L‐NAME treated rats showed higher arterial pressure and heart rate than D‐NAME and CONTROL rats. The hypotensive response and bradycardia due to electrical stimulation did not differ among groups. The density of c‐Fos in the intermediate and commissural caudal NTS, and magnocelular and parvocelular portions of the PVN was higher in L‐NAME treated rats. In conclusion, electrical stimulation of the ADN activated more effectively neurons in the NTS and PVN of L‐NAME induced hypertensive rats. These findings suggest a greater buffering effect of the NTS upon the PVN in this hypertensive model.

Supported by CAPES, CNPq and FAPESP.
GABAB receptors depress glutamate release at C‐fiber afferent synapses in the nucleus of the solitary tract (NTS)
Authors: Fawley Jessica A , Peters James H , McDougall Stuart J , Andresen Michael C
Published: June 2021

Cranial visceral primary afferents follow the solitary tract (ST) to synapse on 2nd order NTS neurons. These afferents consist of both A‐fibers (transient receptor potential vanilloid receptor negative (TRPV1−)) and C‐fibers (TRPV1+). The inhibitory transmitter GABA acts ionotropically at GABAA and metabotropically at GABAB receptors. In horizontal hindbrain slices, ST shocks evoked time‐invariant glutamatergic EPSCs with jitters <200 μs at 2nd order neurons. Capsaicin (TRPV1+ agonist) blocked C‐fiber afferent transmission. We tested whether the GABAB agonist, baclofen (BAC), reduces glutamate release of TRPV1+ afferents on 2nd order NTS neurons. During GABAA block with gabazine, BAC (0.001–20 μM) reduced ST‐EPSC amplitudes and rates of sEPSCs or mEPSCs (in TTX), consistent with presynaptic decreases in glutamate release. BAC effects were more pronounced in 1 mM (physiological) than 2 mM bath calcium, consistent with masking effects of increased probability of glutamate release in high calcium. These data are consistent with presynaptic GABAB control of glutamate release at C‐fiber afferent terminals. Future studies will test whether BAC reduces glutamate release at TRPV1− synapses. Supported by: HL‐088894 (JHP) and HL‐04119 (MCA)
Aging is associated with resistance to the cardiovascular actions of leptin for baroreflex modulation
Authors: Arnold Amy Christine , Diz Debra I
Published: June 2021

Aging is associated with resistance to the metabolic actions of leptin. However, age‐related leptin sensitivity for cardiovascular actions is unknown. Therefore, we determined the effect of leptin microinjection (500 fmol/60 nL) in the solitary tract nucleus (NTS) on baroreflex sensitivity (BRS) for control of heart rate (HR) in older (16 to 20 months) urethane/chloralose anesthetized Sprague‐Dawley (SD) rats with elevated circulating leptin levels. In contrast to the 53% reduction in BRS in younger SD rats, NTS injection of leptin produced no significant change in BRS to increases in pressure (n = 4; 0.93 ± 0.20 baseline vs 0.75 ± 0.23 msec/mm Hg after leptin) in the older SD rats. There were no significant effects of leptin on BRS to decreases in pressure, resting arterial pressure or HR in younger or older SD rats. These data suggest that aging is associated with resistance to the baroreflex actions of exogenous leptin. Whether the elevated circulating leptin levels accompanying age‐related metabolic dysfunction contribute to baroreflex suppression in elderly populations remains unclear, but may provide insight into mechanisms underlying age‐related baroreflex dysfunction. Support: HL‐51952
Role of epinephrine in 5HT1A receptor agonist‐mediated increase in venous tone during hypovolemic shock
Authors: Tiniakov Ruslan L , Scrogin Karie E
Published: June 2021

The 5‐HT1A receptor agonist, 8‐OH‐DPAT, improves hemodynamic parameters and tissue oxygenation during hypovolemic shock via splanchnic sympathetic nerve‐dependent increases in venous tone. To determine if endogenous epinephrine contributes to this response, effects of 8‐OH‐DPAT (30 nmol/kg, iv) and saline on arterial pressure (AP) and mean circulatory filling pressure (MCFP, an index of venous tone) were measured in adrenal‐demedullated (ADMX) and sham‐operated rats during fixed‐pressure (FPH) and fixed‐volume (FVH) hemorrhagic shock. ADMX rats had lower baseline MCFP (5.4 ± 0.1 vs. 7.5 ±0.2 mmHg; P< 0.01) and reached an AP of 50 mmHg with less blood loss (31.3 ± 0.9 vs. 35.0 ± 0.4 ml/kg; P<0.01) than sham‐operated rats. In both hemorrhage models, 8‐OH‐DPAT produced a rapid and persistent pressor effect in sham‐ and ADMX rats (FPH: +29 ± 5 and +28 ± 3 mmHg, P<0.01; FVH: +34 ± 4 mmHg and +36 ± 4 mmHg, P<0.01). This was paralleled by a persistent increase in MCFP in sham‐operated rats (+1.6 ± 0.4 and +1.9 ± 0.4 mmHg, 5 and 35 min after injection, FVH; P<0.01), but only a transient increase in ADMX rats (+1.1 ± 0.4 mmHg, P<0.05, and +0.4 ± 0.4 mmHg, 5 and 35 min post injection, FVH). Saline had no effect on AP or MCFP in either hemorrhage model. Blood volume before FVH (50 ± 1 vs. 53 ± 2 ml/kg) and after treatment with 8‐OH‐DPAT (31 ± 2 vs. 31 ± 5 ml/kg) did not differ between sham‐ and ADMX rats. The data indicate that persistent elevation of MCFP induced by 8‐OH‐DPAT in hypovolemic rats, but not the rise in AP, is mediated, in part, by endogenous epinephrine.

Supported by HL 076162.
Effects of hyper‐ and hypocapnea on choroidal and retinal blood flows and the visual acuity
Authors: Hayashi Naoyuki , Someya Nami , Ikemura Tsukasa
Published: June 2021

We investigated whether hyper‐ and hypocapnea change the blood flows in the choroid and retina, and are related to static visual acuity. Eleven healthy subjects performed three trials. In the control trial (CON), minute ventilation (VE) was not controlled. In the hypocapnea trial (HYPO), the subjects controlled their VE to a target of 20 L/min for 6 min. In the hypercapnea trial (HYPER), the subjects inspired high‐fraction CO2 gas (FICO2=4%) for 6 min. We measured choroidal and retinal blood flows by laser speckle flowmetry, and static visual acuity by using the Landolt C chart. End tidal partial pressure of CO2 differed significantly among CON, HYPO, and HYPER (42±1, 21±1, and 48±1 mmHg, respectively; mean±SE). The choroidal and retinal flows decreased significantly from baseline in HYPO (−17±4%), while they did not change significantly in CON and HYPER. The static visual acuity was significantly lower in HYPO than in HYPER (0.14±0.07 vs. 0.18±0.08, p<0.05). These results indicate that hypocapnia reduces choroidal and retinal blood flows, and suggest that the ocular blood flow influences the visual acuity. (Grant from the Yamaha Motor Foundation for Sports to NH)
Central Ang‐(1–7) enhances baroreflex gain in rabbits with chronic heart failure
Authors: Kar Sumit , Curry Pamela L , Zucker Irving H
Published: June 2021

In chronic heart failure (CHF), arterial baroreflex function is impaired in part by activation of the central renin‐angiotensin system. A metabolite of Angiotensin II (Ang II), Ang‐(1–7), has been shown to exhibit cardiovascular effects that are in opposition to that of Ang II. However, the action of Ang‐(1–7) on sympathetic outflow and baroreflex function is not well understood, especially in CHF. This study aimed to determine the effect of intracerebroventricular infusion of Ang‐(1–7) on baroreflex control of heart rate (HR) in rabbits with CHF. We hypothesized that central Ang‐(1–7) would improve baroreflex function in CHF. Ang‐(1–7) (2 nmol/μl/hour) or artificial cerebrospinal fluid (1 μl/hour) was infused by an osmotic mini‐pump for 4 days in sham and pacing‐induced CHF rabbits (n=5–6/group). CHF rabbits showed depressed baroreflex gain in the conscious state. Ang‐(1–7) treatment increased baroreflex gain (7.4±1.5 bpm/mm Hg vs. 2.5±0.4 bpm/mm Hg, P<.05). Central Ang‐(1–7) improved baroreflex control in CHF by lowering minimum HR and increasing maximum gain. This suggests that modulation of baroreflex function by Ang‐(1–7) may be due to increased vagal tone.

Source of support: PO1 HL‐62222
Mas And AT1 Receptor Expression In Adult Sheep Dorsomedial Medulla
Authors: Arter Alison , Nautiyal Manisha , Shaltout Hossam , Chappell Mark , Diz Debra
Published: June 2021

Recent studies in sheep reveal a programming effect of betamethasone exposure at 80 days gestation such that male and female offspring exhibit elevated pressure and impaired baroreflex sensitivity (BRS) for control of heart rate. Endogenous angiotensin II (Ang II) acting through AT1 receptors attenuates BRS, whereas endogenous Ang‐(1–7) enhances BRS in 6‐week‐old sheep. To determine whether the mas receptor, which has been shown to mediate the actions of Ang‐(1–7) in other species, exists in sheep brain medulla, Western blot hybridizations were performed using membrane homogenates from dorsomedial medulla of 18‐month‐old sheep. To quantify, beta‐actin was used as a loading control for densitometry normalization. Males (n = 6) and females (n = 5) exhibit protein for both AT1 and mas receptors with bands at molecular weights of 50–60 kDa for AT1 and 40 kDa for mas. There were no significant sex or treatment effects observed for the AT1 receptor, however protein expression for the mas receptor was significantly lower in sheep exposed to betamethasone in utero vs control sheep (0.03 ± 0.02 vs 0.33 ± 0.10 relative density units, n = 4–6; p < 0.05). In conclusion, receptor proteins for both AT1 and mas are detected in sheep medulla, and shifts of the mas/AT1 protein ratio toward AT1 may serve as a biochemical substrate for impaired BRS observed in betamethasone‐exposed animals. Support: HD047584, HD017644, HL56973, HL51952.
Fetal disruption of microRNA expression associated with adult onset COPD‐like lung disease in a rat model
Authors: Cohen J Craig , Killeen Erin , Larson Janet E
Published: June 2021

Lung growth and development is dependent upon mechanotransduction‐dependent differentiation. In utero gene transfer via the amniotic fluid with a recombinant adenovirus carrying an antisense CFTR can disrupt stretch and alter development. In this study we altered stretch at E15 in fetal rats. After only 8 months we observed areas of fibrosis throughout the lung. Miroarrays indicated changes in gene expression in these neonatal rat lungs. To determine if microRNAs were altered in these animals, microarrays were performed at P5. In these animals significant changes in microRNAs were detected. Most notably, microRNAs involved in branching morphogenesis were decreased. These data are consistent with the essential role of stretch‐induced differentiation in developmental programming of microRNA dependent gene expression.
Nuclear factor‐kappa beta (NF‐kB) regulates platelet activating factor (PAF) signaling in fetal ovine pulmonary vascular smooth muscle cells (PVSMC)
Authors: Ibe Basil O. , Renteria Lissette S
Published: June 2021

NF‐kB a family of transcription factors regulates cell growth in mammalian cells. PAF binds to its GPCR (PAFr) to phosphorylate and induce nuclear translocation of NF‐kB p65 leading to PVSMC proliferation. We used siRNA‐dependent translation initiation arrest to study a mechanism by which NF‐kB p65 regulates PAF stimulation of PVSMC proliferation. Our hypothesis is that a) PAF induces NF‐kB p65 DNA binding and b) NF‐kB p65 siRNA attenuates PAF stimulation of PVSMC proliferation. For DNA binding, serum starved cells were fed 10nM PAF with and without PAFr antagonists CV 3988 or BN 52021 and incubated for 12 hr. DNA binding was measured by specific ELISA. For NF‐kB p65 siRNA effect, starved cells transfected with the siRNA were incubated for 24 hr with and without 10nM PAF. Cell proliferation was measured by DNA synthesis while PAFr protein expression was measured by Western blotting. In both studies, effect of 10% FBS alone was used as the positive control. In general, PAF stimulated DNA binding which was inhibited by both PAFr antagonists. NF‐kB p65 siRNA significantly attenuated cell proliferation compared to 10% FBS and PAF effect. Inclusion of PAF in siRNA cells did not reverse inhibitory effect of NF‐kB p65 siRNA on DNA synthesis. PAFr expression was inhibited in siRNA‐treated cells. These data show that PAF‐stimulation of PVSMC proliferation occurs via a PAFr‐linked NF‐kB p65 pathway. LA Biomed 513292
Nitric Oxide and Vasopressin Expression during Sepsis
Authors: Oliveira‐Pelegrin Gabriela Ravanelli , Athayde Letícia Antunes , Azevedo Sergio Vicente , Yao Song , Murphy David , Rocha Maria José Alves
Published: June 2021

We investigated the role of centrally produced NO on hypothalamic arginine vasopressin (AVP) expression and release and on cardiovascular response during experimental sepsis. Male Wistar rats were i.c.v injected with the non‐selective NO synthase (NOS) inhibitor L‐NAME, or aminoguanidine (AG), a selective inhibitor of the inducible isoform (iNOS). After 30min sepsis was induced by cecal ligation and puncture (CLP) causing increases in NO plasma levels and heart rate (HR) and a reduction in arterial pressure (MAP) and AVP expression ratio (AVPR) in the supraoptic (SON) and paraventricular (PVN) nuclei. AVP plasma levels (AVPp) increased, but only in the early phase. L‐NAME pretreatment, reduced NO production and increased MAP and did not change HR. AVPp further increased in the early phase but decreased in the late phase while AVPR decreased in both phases. AG i.c.v injected did not change substantially the increase of NO plasma levels but increased MAP in the initial phase of sepsis. AVPR increased only in the SON, and AVPp remained all time elevated. These results show that increased central NO production differentially inhibits AVPR in SON and PVN, contributing to basal AVPp and hypotension in the late phase of sepsis.

Financial support: FAPESP
TRPV1 channels contribute to hyperosmotic‐induced release of vasopressin from somata and dendrites of magnocellular neuroendocrine cells in supraoptic punches
Authors: Beitzel Christy Sue , Castillo Jason , Valdez Matt , Shahidzadeh Anoush , Spurgin Kurt , Calma Rose , Curras‐Collazo Margarita
Published: June 2021

Magnocellular neuroendocrine cells (MNCs) in the supraoptic nucleus (SON) of the hypothalamus release the antidiuretic hormone, vasopressin (VP), in response to hyperosmotic and hypovolemic stimulation. Transient Receptor Potential Vanilloid 1 (TRPV1) receptor channels mediate osmosensitive electrical responses in MNCs and systemic VP release (Naeini et. al., 2006) but the specific mechanism linking TRPV1 channels and secretion of VP has yet to be determined. To examine the role of TRPV1 channels in somatodendritic VP release during hyperosmotic stimulation we treated acutely dissected SON punches in vitro with 350 mOsm/l Locke's solution in the presence and absence of the TRPV1 antagonist, 5‐iodoresiniferatoxin (SB366791). VP values were quantified using enzyme‐linked immunoassay. Hyperosmotic stimulation enhanced VP release and 1.5μM SB366791 attenuated this (p<0.05; n= 39). Mean (±s.e.m.) values for extracellular VP levels in isosmotic, hyperosmotic and hyperosmotic/SB366791 were 7.15±1.7, 11.1±2.8, 3.68±0.7 pg/ml μg protein, respectively. Doses of 0.15 and 10μM also reduced VP levels to 5.5±1.0 and 5.1±1.0, respectively. Immunohistochemistry showed TRPV1 immunoreactivity in SON MNCs. We conclude that TRPV1 channels in SON MNCs are activated during hyperosmotic stimulation and are required for somatodendritic VP secretion during osmotic challenge. (Supported by UC MEXUS)
Second hand smoke exposure mediates oxidative modification of plasma apolipoprotein E
Authors: Narayanaswami Vasanthy , Gallo Carlos , Amaya Max , Tamamizu‐Kato Shiori , Akintunde Olayemi , Uyeminami Dale , Pinkerton Kent , Uchida Koji , Kosaraju Malathi
Published: June 2021

The objective of our study was to assess if second hand smoke exposure predisposes subjects towards developing heart disease. We monitored the effect of reactive aldehydes in tobacco smoke on the status of plasma apolipoprotein E (apoE). ApoE plays a critical role in regulating plasma cholesterol homeostasis, since it serves as a ligand for the low density lipoprotein family of receptors. ELISA indicated that rats exposed to low doses of tobacco smoke had lower plasma apoE levels compared to the control group. Immunoprecipitation analysis revealed that the smoke‐exposed group also had higher levels of modified apoE in their lipid‐free fractions. There were no differences between the two groups in lipid peroxidation products levels or in the susceptibility of the lipoproteins to lipid peroxidation. In vitro analysis using recombinant apoE provided further support for modification of essential lysines. Our results suggest that the occurrence of oxidatively modified apoE in a lipid‐free state can result in decreased clearance of plasma lipoproteins. We propose that sustained second hand smoke exposure can potentially lead to a proatherogenic profile. Source of research support: Tobacco Related Disease Research Program, American Heart Association, NIH R25 HL096365‐01, CSULB funding and SCAC award.
High Egg Cholesterol Consumption May Not Affect Blood Serum Cholesterol Levels in Elite Athletes in Training
Authors: Bui Steve , Oliver Jonathan , Mardock Michelle , Beihl Adam , Riechman Steven E.
Published: June 2021

Background

Due to its high cholesterol content, limiting the intake of egg yolks is a common recommendation; however, recent studies have shown that blood cholesterol levels may be more dependent on other factors such as physical activity levels and genetic predispositions, than on actual cholesterol intake. Therefore, we hypothesized that very high cholesterol consumption in the form of egg yolks will not increase blood cholesterol levels in elite collegiate power lifters during training.

Methods

Seven individuals were recruited for this study (age: 23±3.6; height: 66.7±4.7 in; body fat: 17.6±9.3%; weight: 83.2±17.8 kg). Subjects were assigned to one of two supplement groups paired by sum of 1RMs to lean body weight. High cholesterol supplement group was supplemented with 20 mg•kg−1•lean body mass−1 •day−1 of cholesterol via egg yolks (HC, N=4) while the lower cholesterol group was supplemented with equivalent egg control (LC, N=3) to meet 8 mg•kg‐1•lean body mass‐1•day‐1. Blood measurements were taken prior to supplementation and after nine weeks of training/supplementation.

Results

Total cholesterol decreased in HC (−11.8±18.4 mg•dl−1) but increased in LC (21.7±9.5 mg•dl−1) after nine weeks (P<0.05). HDL followed a similar pattern (−11.3±6.8 HC and 4.7±6.4 LC mg•dl−1, P<0.05), while LDL levels did not change (5.3±.11. HC and 8.0±.14.4 LC mg•dl−1, P>0.05).

Conclusion

It is unclear what may have caused a decrease in total cholesterol and HDLs while maintaining LDL levels. The relationship of dietary cholesterol to blood parameters is not straightforward as generally perceived and exercise training at the elite level may alter this relation.
Expression of Angiotensin II Subtype 1a Receptor (AT1a) During Pregnancy in Mouse
Authors: Chen Kai , Rose James C
Published: June 2021

Objective

The AT1a receptor plays an important role in blood pressure regulation during pregnancy but its expression in gestation is not well defined. There is also significant interaction between AT1a and angiotensin II subtype 2 receptors (AT2). Therefore, we examined AT1a expression in wild type(WT) and AT2 knockout mice (AT2(−/−)) throughout pregnancy to determine the pattern of expression and if the AT2 receptor influences any pregnancy‐related changes.

Methods

Six mice from each group were sacrificed in early‐, mid‐ and late gestation. Tissues such as kidney and placenta were collected. Western blot was used to examine the expression of the receptor. ANOVA followed with Newman‐Keuls test was used to analyze data from kidney, t test was used to analyze data from placenta.

Results

In placenta, compared to mid gestation, AT1a decreased in late gestation in WT mice (0.63±0.13 vs. 0.27±0.07*) but not in AT2(−/−) mice (0.77±0.17 vs. 0.75±0.07). Similarly, in kidney, compared to early gestation, AT1a was lower in mid‐ and late gestation in WT mice (1.16±0.03, 0.91± 0.12*, 0.81±0.05*) but not in AT2(−/−) mice (0.79±0.05, 0.66±0.05, 0.78±0.12).

Conclusion

Expression of the AT1a decreases during pregnancy in placenta and kidney in normal but not in AT2(−/−) mice. AT2 receptors might play an important role in AT1 expression variation during pregnancy in mice.
High muscle mass in Oregon women is associated with decreased antioxidant expression in the term placenta
Authors: O'Tierney Perrie Faye , Cedar Anna , Morris Cynthia , Thornburg Kent L
Published: June 2021

Objective

Placental oxidative stress is an imbalance between antioxidants and reactive oxygen species and is known to compromise fetal growth. We hypothesized that high maternal muscle mass and body mass index (BMI) in early pregnancy will lead to suppressed expression of placental antioxidant systems.

Methods

Women were categorized into groups based upon arm muscle area (AMA) [low: 20.1 ± 3.4 and high: 71.3 ± 16.2 cm2] and BMI [low: 19.3 ± 1.4 and high: 38.4 ± 2.5 kg/m2]. Term placental antioxidant gene expression, specifically catalase, superoxide dismutase (SOD) 1 and 2, and glutathione peroxidase (GPX) 1 and 4, was quantified by QPCR. 8‐isoprostane, a marker of oxidized lipid, was measured in maternal and fetal plasma.

Results

SOD2 protein and GPX1 mRNA levels were decreased (P<0.05) in women with high AMA. Antioxidant levels were not changed in placentas of women with high BMI. 8‐isoprostane increased with maternal BMI (R= 0.51, P<0.05) but not AMA (R=0.36), while fetal levels showed no association with maternal body type.

Conclusions

a) Antioxidant expression was depressed in high AMA mothers as hypothesized without increased 8‐isoprostane. b) Contrary to the hypothesis, high BMI women had a different response. Placental antioxidant levels were unchanged while oxidative stress was increased in these mothers. Supported by the Collins Medical Trust, Northwest Health Foundation, Holtzman Foundation.
Folic acid mitigated homocysteine‐mediated decrease in bone blood flow and bone remodeling
Authors: Kandel Madhavi , Tyagi Neetu , Qipshidze Natia , Munjal Charu , Basu Poulami , Givvimani Srikanth , Abe Oluwasegun A , Mishra Paras K , Sen Utpal , Tyagi Suresh C
Published: June 2021

Treatment with folic acid has been shown to decrease the risk of osteoporosis. Although homocysteine (Hcy) accumulated collagen in bone and contributed to decrease in bone strength and density, the mechanism of Hcy‐induced bone loss and collagen remodeling was unclear. To test the hypothesis that homocysteine‐mediated decrease in bone strength is in part due to decrease in bone blood flow and remodeling, we used wild type (WT) and hyperhomocysteinemia (cystathionine beta synthase heterozygote knockout, CBS−/+) mice treated with and without folic acid (FA 300 mg/kg in drinking water). The tibial arterial bone blood flow was measured by laser Doppler and ultrasonic flow probes. The tibial bone density was measured by a digital micrometer. The bone homogenates were analyzed for bone remodeling by measuring matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP). The results suggested that there was decrease in tibial arterial blood flow in CBS−/+ mice. The bone density was also reduced in CBS−/+ mice. There was increase in MMP‐2 and ‐9 protein level in CBS−/+ tibia. The levels of TIMP‐3 were increased, where TIMP‐4 was decreased in CBS−/+ tibia. Interestingly, the treatment with FA mitigated the decrease in TIMP‐4 in CBS−/+ tibia. We concluded that folic acid treatment mitigated the decrease in bone blood flow by increasing TIMP‐4 and strengthening the bone.
A multi‐media CD for teaching biomedical research design and biostatistics
Authors: Ware S K , Marcuson R L , Ware D G
Published: June 2021

We designed a multi‐media CD based on a PowerPoint format for teaching biomedical research design and associated research analyses (biostatistics). The CD materials are entirely self instructive. The user can access each chapter in sequence (recommended to teach research design and analysis), go to any desired chapter from an initial menu (suggested when using the CD for quick review), or access the relatable chapter by answering some basic questions about anticipated or concluded research (recommended when using the CD to assist with probable research design or the analysis of assembled data). There are 36 chapters, including data graphing, descriptive statistics, data distributions, probability, comparing groups, ANOVA, simple regression, multiple regression, correlation, and non‐parametric statistics. Many of the research designs are accompanied by 2–10 minute embedded movies demonstrating the basics of statistical analysis of that design using SPSS software. The CD can be used as an adjunct for introductory to mid‐level research courses, or as a standalone teaching (or review) tool. There are numerous examples of completed biomedical studies and their statistical interpretations. It would require approximately 25–30 hours to complete the CD if all chapters were studied (1287 PowerPoint slides, and 24 movies). Occasional interactive quizzes are used to highlight important concepts.
Anatomy plays an important role in a health science outreach to underserved youths in a rural state
Authors: Klinkhachorn Penprapa S.
Published: June 2021

Created as a community‐campus partnership, the Health Science & Technology Academy exposes underserved high school youths to health sciences, furthering their interest in college, and pursuing careers in WV. Programs are Fun with Science, Forensic Science, & Biomedical Summer Institute. Eligible students are African American, low income, rural residents, or the first in their family to go to college. Anatomy is one of eight biomedical groups offered. Activities are designed to keep it fun, engaging, and interactive. Props are used to stimulate critical thinking and problem solving skills with clinical application. A gross lab tour offers a glimpse of how college students learn anatomy through dissection. Jeopardy is used as a tool to test what they learn in a fun game format. They learn a lot from their group inquiry, and from visiting the gross lab. We influence their decision to attend college and choice of health careers. 97% of HSTA graduates go to college vs. 56% of WV students. Medical student volunteers contribute positively, while inspiring students and earning community service hours. Satisfied teachers gain new ideas and science knowledge. In conclusion, anatomy is a key component of HSTA in providing opportunities for these youths and in increasing the number of health science professionals in WV, that otherwise may have been lost through the cracks. Supported in part by NIH‐NCCR # 10009490.28.1003654R
Incorporating a primary literature‐based project into a non‐majors pathophysiology course
Authors: Walton Kristen LW
Published: June 2021

Primary literature is an excellent tool for students to explore current research in biology and engage in the process of science. However, using primary literature in non‐majors courses presents several challenges, since it is often students’ first exposure to primary literature, and their background in technical reading and research methods is typically limited. Students in an upper‐division, non‐majors pathophysiology course were required to write a paper which included 1) a summary of the etiology, pathophysiology, and treatment of a human disease, and 2) an analysis of a current primary article related to the disease. Reference lists were turned in 1 month prior to the project due date so feedback on appropriate reference selection could be provided. Students were surveyed for their prior experience reading primary literature and for their evaluation of their learning gains from the project. Although most students had written research papers as part of nonscience courses, few reported prior experience with primary literature. Several students expressed enthusiasm for having the opportunity to research a disease of their choice. Although they found the primary literature challenging to read, many students reported that the project was a useful learning experience. These results suggest that this type of project is a successful mode of incorporating primary literature into a non‐majors biology course.
Anisotropy in the Frontal Sinuses of Bighorn Sheep and Its Implications for Understanding Pneumatization
Authors: Farke Andrew A.
Published: June 2021

In bighorn sheep (Ovis canadensis), greatly expanded frontal sinuses overlie the endocranial cavity and enter the horncores. A number of bony struts further subdivide the sinuses. Previous workers have suggested that the struts function as shock absorbers and/or strengthen the sinus against the forces of head butting. Under both scenarios, it is predicted that the struts should be oriented parallel to typical loads applied to the horns. In order to test this hypothesis, skulls of male O. canadensis were CT scanned, and structural anisotropy for the struts within the frontal sinus was estimated using the star volume distribution method. Measurements were taken at the base and midpoint of the horncores. Strut orientations were highly anisotropic. Struts were oriented parallel to the long axis of the horn at its base and oriented medio‐laterally distally. These results are contrary to expectations, suggesting that sinus morphology within O. canadensis is not primarily shaped by applied loads. Instead, the orientation of the struts may simply reflect the direction of expansion of the pneumatic diverticulum during pneumatization of the skull. Funded by SICB and an NSF GRF.
Lifelong sedentary behavior aggravates detrimental age associated effects on bone structure of C57BL/6 mice
Authors: Fonseca Helder Martins , Gonçalves Daniel Moreira , Figueiredo Pedro Carvalho , Mota Paula Gonçalves , Duarte José Alberto
Published: June 2021

The aim of this study was to compare the femoral bone structure of lifelong sedentary vs active C57BL/6 mice. Thirty male C57BL/6 mice, aged 2 months, were either: i) sacrificed after arrival (young group; Y; n=10); ii) kept in cages equipped with running wheels, where they could perform voluntary running (aged active group; AA; n=10); iii) kept in cages without running wheel (aged sedentary group; AS; n=10). After 23 months of differential housing AS and AA animals were also sacrificed. In all animals the right femur was collected and processed for histomorphometryc analysis of both epiphyses and mid diaphysis. Right hind limb muscles were collected for citrate synthase (CS) activity determination to confirm physically active and sedentary behaviors.

Differences in trabecular microarchitecture and cortical bone geometry were identified between AA and AS groups. AA mice showed significantly increased trabecular perimeter (Tb.Pm) and trabecular number (Tb.N) and decreased trabecular separation (Tb.Sp) at both epiphyses when compared to AS mice. Differences in osteocyte density (Oc.N/mm2) were identified between AS and Y mice but not between AA and Y mice. Our results evidence that skeletal changes usually indentified as a result of ageing, are at least in some extent, due to sedentary behavior. Maintenance of a physically active lifestyle is therefore essential for delaying changes in bone quality throughout life.

Grant Funding Source: FCT grant SFRH/BD/38110/2007
Collagen XXIV null mice have osteoporotic bones
Authors: Gordon Marion K , Feng Bo , Laub Friedrich , Koch Manuel , Ramirez Francesco
Published: June 2021

Collagen XXIV, discovered as a cDNA, has a typical C‐propeptide domain, indicating the molecule is a member of the fibrillar collagens. The amino terminal non‐collagenous domain is large, similar to those of fibrillar collagen alpha1(V), alpha1(XI) and alpha1(XI) chains. The triple helical domain is about 100 amino acids shorter than other fibrillar collagen chains and contains an imperfection (Koch et al., JBC 278: 43236, 2003). The gene is activated late in the osteoblast differentiation program, and is regulated by CREB‐AP1 (Matsuo et al., JBC 281:5445, 2006; Matsuo et al., Conn Tiss Res 49:68, 2008). Our objective was to evaluate the importance of collagen XXIV to the architecture of bone by examining null mice. MicroCT analysis of the femurs of 5 month old null mice were compared with those of age matched wild type mice. The cortical bone was less dense in the null mice and cross sections through the distal femur displayed fewer trabeculae. 3D reconstructions indicated that the femurs of the null mice had the same bone volume as the wild type femurs, but that the bone was less dense, having an osteoporotic appearance. Conclusion: Collagen XXIV is important for proper bone density.
Transgenic Labeling of Chondrocyte and Osteoblast Lineages in Xenopus laevis Tadpoles
Authors: Kerney Ryan
Published: June 2021

The extent to which tadpole cells contribute to adult tissues and organs is a long‐standing question in amphibian metamorphosis. These contributions are particularly interesting in skeletal metamorphosis, where the cartilaginous tadpole skeleton is largely replaced by de novo cartilage and bone formation in the adult. Three basic pathways of cellular differentiation are possible. First, larval cells may persist in a single differentiated state to give rise to an adult structure of the same tissue type (e.g. cartilage). Second, larval cells may transdifferentiate from one differentiated state to another during metamorphosis (e.g. cartilage to bone). Third, cellular progenitors to adult structures may persist as mesenchyme in the tadpole, and only achieve terminal differentiation during metamorphosis (e.g. mesenchyme to cartilage and/or bone). This project explores all three of these differentiation pathways during skeletal metamorphosis through novel transgenic labeling of cell populations and cellular lineages in Xenopus laevis. Wnt1, sox10, col2a1 and osterix reporter constructs were used to drive green fluorescent protein (GFP) expression in the neural tube, neural crest, chondrocytes, and osteoblasts respectively. These live labels allow the visualization of skeletogenesis in vivo. In conjunction with cre‐recombinase‐dependent lineage labeling, these reporters reveal both the extent to which differentiated larval chondrocytes contribute to the adult skeleton, and the location of putative skeletogenic precursors that are developmentally quiescent during tadpole stages. These pathways of cellular differentiation have implications for both the mechanisms of skeletal development and the evolution of anuran metamorphosis.

Grant Funding Source: NSERC
Matrix metalloproteinase 13 (MMP13) can cleave the protease‐sensitive hinge region of theTransforming Growth Factor β (TGFβ) large latent complex
Authors: Reese Betsy , Routson Stephanie M , Lau Shukkwan , Lombard Frederick , Selim Abdulhafez A , D'Angelo Marina
Published: June 2021

In this study, we demonstrate that MMP13 can utilize the protease‐sensitive hinge region of the TGFβ large latent complex as a substrate. Our lab has previously demonstrated that chondrocytes produce a unique large latent TGFβ complex that contains MMP13 in non‐covalent association. Our bioinformatics model suggests that MMP13 associates with the complex in such a way as to line up the catalytic domain with the protease sensitive hinge region, the site of release of the complex from extracellular matrix storage. Kinetic analysis of MMP13 catalytic domain digestion of a fluorescence‐labeled peptide, REHGARS, (the site of release of the TGFβ large latent complex from the extracellular matrix), indicated that the peptide was digested by MMP13 (30 minute slope = −2.580 and p‐value = 0.001 compared to substrate alone), and this activity was sensitive to a general inhibitor of MMP activity. A scrambled sequence of the peptide was not digested by MMP13 (30 minute slope = −0.2196). MMP2 and MMP9 catalytic domains were not as efficient in digestion of the substrate, but proteases present in cartilage extracts from chick embryonic sterna were able to digest the hinge region substrate. This is the first study of its kind indicating the ability of MMP13 to utilize the protease‐sensitive hinge region of the TGFβ large latent complex as a substrate, indicating a role for MMP13 in TGFβ activation. The implications of this finding provide a mechanism of release of matrix stored TGFβ in normal cartilage maturation as well as the aberrant release of articular cartilage stores of TGFβ in osteoarthritis.

This work was supported in part by a grant from the Center for Chronic Disorders of Aging.
Translational potential of patient‐specific human pluripotent stem cells
Authors: Agarwal Suneet
Published: June 2021

Pluripotent stem cells are defined by two features: self‐renewal and the ability to differentiate into any cell type. Multiple methods now exist to reprogram differentiated cells from an adult animal to a state of pluripotency. In turn, it is possible to differentiate these reprogrammed cells into specific tissue progenitors in vitro. Combined, these advances provide the basis for development of patient‐specific cell replacement therapies, which may address the donor incompatibility and availability problems pervasive in modern tissue transplantation. We are generating patient‐specific pluripotent cell lines using “direct” reprogramming, wherein fibroblasts are transduced with defined factors and cultured to yield “induced pluripotent stem” (iPS) cells. We have derived iPS cell lines from the somatic cells of patients with bone marrow failure syndromes including dyskeratosis congenita and Pearson syndrome, which are caused by telomerase gene mutations and mitochondrial DNA deletions, respectively. Unexpectedly, we find that the underlying genetic lesions in these cells can be compensated or corrected during propagation in the pluripotent state. These results demonstrate the value of patient‐specific iPS cells as disease models, and further the concept of autologous iPS based cellular therapy for genetic hematologic disorders.
Human epithelial stem cells in corneal regeneration and epidermal gene therapy
Authors: De Luca Michele , Rama Paolo , Mavilio Fulvio , Pellegrini Graziella
Published: June 2021

Adult stem cells are cells with a high capacity for self‐renewal that can produce terminally differentiated progeny. Stem cells generate an intermediate population of committed progenitors, often referred to as transit amplifying (TA) cells, that terminally differentiate after a limited number of cell divisions. Human keratinocyte stem cells are clonogenic and are known as holoclones. Human corneal stem cells are segregated in the limbus while limbal‐derived TA cells form the corneal epithelium. Self‐renewal and proliferation and deifferentiation of limbal stem cells are regulated by the ΔNp63 (α,β and γ), C/EBPδ and Bmi1 transcription factors. Cultivated limbal stem cells generate sheets of corneal epithelium suitable for clinical application. We report long‐term (up to 10 years) clinical results obtained in an homogeneous group of 112 patients presenting with corneal opacification and visual loss due to chemical burn‐dependent limbal stem cell deficiency. The corneal epithelium and the visual acuity of these patients have been restored by grafts of autologous cultured limbal keratinocytes. Clinical results were assessed by Kaplan‐Meyer, Chi‐square, Mann Whitney, Mc‐Nemar and Kruskal‐Wallis statistical analyses.

Mutations in genes encoding the basement membrane component laminin 5 (LAM5) cause junctional epidermolysis bullosa (JEB), a devastating and often fatal skin adhesion disorder. Epidermal stem cells from an adult patient affected by LAM5‐β3‐deficient JEB were transduced with a retroviral vector expressing the β3 cDNA and used to prepare genetically corrected cultured epidermal grafts. Nine grafts were transplanted onto surgically prepared regions of the patient's legs. Engraftment was complete after 8 days. Synthesis and proper assembly of normal levels of functional LAM5 was observed, together with the development of a firmly adherent epidermis that remained stable for the duration of the follow‐up (3.5 years) in the absence of blisters, infections, inflammation or immune response. Proviral integration site analysis indicated that the regenerated epidermis is maintained by a defined repertoire of transduced stem cells. These data show that ex vivo gene therapy of JEB is feasible and leads to full functional correction of the disease.
Differential effects of acute gonadal steroid treatment on neuronal survival in the brainstem following C3 hemicontusion
Authors: Monaco Gina N , Khan Talat A , Ogata Kengo , Houle John D , Jones Kathryn J
Published: June 2021

Following gonadectomy, adult male and female Sprague‐Dawley rats underwent a cervical level 3 hemicontusion spinal cord injury (C3HC SCI) and were randomized to receive testosterone (T), estrogen (E), or sham pellet, and True Blue (TB)‐soaked gelfoam was placed into the lesion cavity to retrogradely label injured supraspinal neurons. At 4 weeks post‐C3HC, brains and cervical spinal cords were removed, sectioned, fixed, mounted, and examined with fluorescence microscopy for TB‐labeled neurons. Neurons in the red nucleus and lateral vestibular nuclei were counted from alternating sections. For the lateral vestibular neurons: sham‐treated males exhibited greater baseline cell survival than did females following injury, T had a positive effect on cell survival in female animals, but E had a negative effect on cell survival in female animals. In the red nucleus, cell survival was similar between the sham‐treated sexes, T did not have an effect on cell survival in females, and E had a negative effect on cell survival in females. The results suggest there are sex differences in the response to injury in different brain stem nuclei, as well as differential and regional effects of T versus E treatments on cell survival. This work was supported by VA Rehab R&D Merit Review Project # B4952I (KJ Jones & JD Houle).

Grant Funding Source: VA Rehab R&D Merit Review Project # B4952I (KJ Jones & JD Houle)
Olfactory ensheathing cells (OECs) transplantation in spinal cord prolongs the survival of mutant SOD1 (G93A) ALS rats through neuroprotection and remyelination
Authors: Zhou Changman , Bao Jianling , Chen Lin , Chen Chunhua , Liu Jun , Huang Hongyun
Published: June 2021

Amyotrophic lateral sclerosis (ALS) is a fatal progressive neurodegenerative disease. SOD1G93A rat(n=20), medium+SOD1G93A rat(n=20), OECs+SOD1G93A rat(n=20), and another 20 wild type rats as control. 5μL(1×105) OECs was injected into the dorsal funiculus of the thoracic spinal cord (T7) through a glass micropipette at depths of 0.7 mm and 0.4 mm (0.5 lL). Kaplan Meier survival analysis revealed a significant increase (7 days) in the survival time of the OEC+SOD1G93A rats. Body weight record and Inclined board test showed a significant difference from onset 7days to 11days (P<0.05). Motor neuron count per ventral horn of thoracic spinal cord showed a significant motor neuron loss in SOD1G93A rats(P<0.001). Immunohistochemistry and Western blot ChAT analysis supported the motor neuron count. Confocal microscope images of tissue sections indicated that the transplanted OEC could have survived more than four weeks and migrated as long as 8.4mm through the spinal cord. Evidence of remyelination was captured. In conclusion, the transplanted OECs could serve as a source of neuroprotection and a remyelination to positively modify the ALS‐specific microenvironment.