bluuebunny/crossref_metadata_2025 huggingface dataset:
Pregnancy Up‐regulate Genes Involved in Glucose and Lipids Metabolism in the Left Ventricle of Rat
Authors: Sonanez‐Organis Jose , Hernandez‐Palomares Magally , Virgen‐Ortiz Adolfo , Rosas‐Rodriguez Jesus , Ortiz Rudy
Published: June 2021

Hypertrophic cardiomyopathy up‐regulates HIF‐1α and PPARγ to cooperatively to mediate important changes in cardiac metabolism that are characteristic of and contribute to common forms of heart disease. HIF‐1α activates glycolytic genes, and PPARγ facilitates the uptake of free fatty acids uptake and genes involved with glycerol‐lipid biosynthesis in response to pathologic stress. Therefore, these changes increase the rate of glycolysis and glucose‐to‐lipid ratio via glycerol‐3‐phosphate pathway, apoptosis, and contractile dysfunction. However, the expression of genes regulated by HIF‐1α and PPARγ in physiologic hypertrophy induced by pregnancy and its reversible process (postpartum) are not well defined. In the present study, we quantified HIF‐1α (HK2, PFKM, GAPDH and PK4) and PPARγ (GPAT and GPD1) target genes before (not pregnancy, NP), during late pregnancy (LP, 21 days) and after pregnancy (PP, 7 days) in the left ventricle of rats. Levels of mRNA for the glycolytic genes HK2, PFKM and GAPDH increased 1.6‐, 3.2‐ and 2‐ fold during LP and decreased to basal level after PP, respectively, while PK mRNA levels decreased during LP and returned to basal level after PP. The glycerol‐lipid biosynthesis genes GPAT and GPD1 increased 14‐ and 3‐ folds during EP and decreased to basal levels after PP, respectively. Results demonstrate that pregnancy induces the expression of glycolytic and glycerol‐lipid biosynthesis genes suggesting a shift in cardiac metabolism by activation of HIF‐1α and PPARγ.
The Degree of Myocardial Injury During the Reperfusion Depends on the Oxygen Surrounding the Isolated Heart During Global Normothermic Ischemia
Authors: Bopassa Jean C.
Published: June 2021

During global ischemia, hearts kept “in air” in a humid chamber require ~120 min of reperfusion to establish the myocardial infarction while hearts “immersed” in a physiological buffer require a shorter reperfusion period ~30 min. As oxidative stress favors myocardial injury during reperfusion, we hypothesized that a higher level of oxygen surrounding hearts “immersed” during ischemia favors the myocardial injury during reperfusion. Isolated mice hearts were perfused using a Langendorff apparatus with Krebs Henseleit (KH) buffer oxygenated with 95%O2+5%CO2 at37°C. Hearts were subjected to 18 min global ischemia and kept “in air” or “immersed” in KH followed by different reperfusion durations (40, 60 or 90 min). Cardiac function was recorded and myocardial infarction assessed by TTC staining. ROS generation was measured in isolated mitochondria after 10 min reperfusion. After 40 min reperfusion, myocardial infarct size was much larger in hearts conserved “immersed” compared to “in air” during ischemia. Furthermore, cardiac functional recovery and infarct size at 40, 60 and 90 min of reperfusion kept increasing with “in air” ischemia while with “immersed” ischemia the values had reached steady‐state at 40 min. The role of oxygen‐induced damage was confirmed by replacing oxygenated‐KH with N2‐bubbled‐KH surrounding the heart during “immersed” ischemia. After 40 min reperfusion, cardiac functional recovery was improved and myocardial infarct size was reduced in the group immersed in KH N2‐bubbled when compared to those in oxygenated KH. Mitochondria ROS production was reduced in the group immersed in N2‐bubbled KH compared to those in oxygenated KH. In conclusion, the level of oxygen surrounding hearts during ischemia determines the injury during the reperfusion.
Habitual Aerobic Exercise Does Not Significantly Influence Age‐related Microvascular Endothelial Dysfunction in Healthy Estrogen‐deficient Postmenopausal Women
Authors: Strahler Talia , Pierce Gary , Seals Douglas , Santos‐Parker Jessica
Published: June 2021

Aging causes macro‐ and microvascular endothelial dysfunction, as assessed by endothelium‐dependent dilation (EDD), which can be prevented and reversed by habitual aerobic exercise (AE) in men. However, a beneficial effect of AE on macrovascular EDD has not been consistently shown in estrogen‐deficient postmenopausal women, and microvascular EDD has not been assessed. We determined forearm blood flow in response to incremental brachial artery infusion of acetylcholine (FBFACh), a measure of microvascular EDD, and brachial artery flow‐mediated dilation (FMD), an assessment of macrovascular EDD, in 8 premenopausal sedentary (PrS; 25.5±2 yrs; VO2max = 36.9±2.6 ml/kg/min), 28 estrogen‐deficient postmenopausal sedentary (PoS; 61.8±1 yrs; VO2max = 24.5±0.9 ml/kg/min), and 7 estrogen‐deficient postmenopausal trained (PoT; 58.6±2 yrs; VO2max = 40.6±2.4 ml/kg/min) women. Peak and area under the curve (AUC) FBFACh was lower in PoS vs. PrS (19.5±1.2 vs. 29.9 ml/100 ml tissue/min and 133.4±8.8 vs. 211.5±28.7 AUC, respectively, P<0.05) women. In PoT, peak and AUC FBFACh was lower than PrS, but not different from PoS (20.1 ml/100 ml tissue/min and 102.8±21.8 AUC, respectively, P<0.05 and P>0.05, respectively) women. FMD was 28% and 42% lower in PoS and PoT, respectively, vs. PrS women, and there was no difference in FMD between PoS and PoT (P>0.05) women. These findings suggest that habitual AE does not protect against age‐related macro‐ and microvascular endothelial dysfunction in estrogen‐deficient postmenopausal women.
Dietary Sodium Loading Increases Central Systolic Blood Pressure More in Middle‐Aged Compared to Young Salt Resistant Adults
Authors: Muth Bryce , Brian Michael , Matthews Evan , Ramick Meghan , Lennon‐Edwards Shannon , Farquhar William , Edwards David
Published: June 2021

Excess dietary sodium intake has been linked to increased incidence of cardiovascular disease and the development of hypertension. We sought to determine the effect of short‐term dietary sodium loading on central blood pressure in young (YG; n=46, 26±1 yrs) and middle‐aged (MA; n=27, 51±1 yrs) normotensive, salt resistant adults. Subjects were randomized to 7 days of low sodium (LS: 20 mmol/d) and 7 days of high sodium (HS: 300 mmol/d). Salt‐resistance was defined as mean 24‐hour MAP change 蠄5 mmHg between diets (LS: 87±1 vs. HS: 86±1 mmHg, p > 0.05). On the last day of each diet, carotid‐femoral pulse wave velocity (PWV) and the synthesis of a central aortic pressure waveform (by radial artery applanation tonometry and generalized transfer function) and wave separation analysis were performed. When compared to the LS diet, the HS diet elicited an increase in central systolic blood pressure (cSBP) in both YG (LS: 95±1 vs. HS: 98±1 mmHg, p < 0.05) and MA (LS: 107±2 vs. HS: 116±3 mmHg, p < 0.05), with a larger increase seen in MA (YG: 3±1 vs. MA: 9±2, p < 0.05). In MA, HS elicited greater central forward wave amplitude (LS: 26±1 vs. HS: 30±1 mmHg, p < 0.05) and central reflected wave amplitude (LS: 18±1 vs. HS: 22±1 mmHg, p < 0.05) but no difference was seen in YG. PWV was not altered by 7 days of HS in either group (p>0.05). These data suggest that higher sodium intake is associated with a greater increase in cSBP in MA compared to YG adults that may be due to increases in forward and reflected wave amplitudes.

Supported by NIH Grant R01 HL104106
Schild Analysis of In Vivo Theophylline Antagonism of Adenosine in Fetal Sheep Coronary Arteries
Authors: Jonker Sonnet , Giraud George , Louey Samantha
Published: June 2021

Adenosine causes near‐maximal vasorelaxation of fetal coronary arteries but adenosine receptor antagonism in this bed has not been characterized. We performed Schild analysis of theophylline (adenosine antagonist with similar affinity for receptors A1, A2a and A2b) in near‐term fetal sheep coronaries. Fetuses (n=4) were instrumented with vascular catheters and a circumflex transit‐time flow probe. Vascular pressures (corrected to amniotic pressure) and coronary flow (corrected to driving force) were recorded continuously. Heart rate was controlled with propranolol and atropine. Theophylline (bolus then continuous infusion) was given into the right atrium. Graded infusions of adenosine into the left atrium stimulated increased coronary flow. Theoretical adenosine concentrations were calculated from infusion rates and assumed left ventricular output; theophylline concentrations were measured in arterial blood. The plateau was constrained at 100% of adenosine‐stimulated coronary flow, while the floor was unconstrained, allowing for theophylline suppression of baseline flow due to endogenously produced adenosine. Log(EC50), pA2, Schild and Hill slopes were constrained to share values within one fetal experiment. Schild analysis yielded a mean global R2=0.98, EC50=0.88±0.41uM(sd), Hill slope=2.5±0.4, Schild slope=0.94±0.63 and pA2=4.8±0.4. A Schild slope close to 1 indicates theophylline acts as a competitive antagonist of adenosine in the fetal coronaries in this dose range, thus pA2=pKb. These data suggest that maternal methylxanthine consumption may alter fetal coronary perfusion.

Supported by NICHD R01HD071068 and P01HD034430.
Regional Variation in Arterial Stiffening and Dysfunction in Western Diet‐Induced Obesity
Authors: Bender Shawn , Castorena‐Gonzalez Jorge , Garro Mona , Reyes‐Aldasoro Constantino , Sowers James , DeMarco Vincent , Martinez‐Lemus Luis
Published: June 2021

Central vascular stiffening, determined in vivo via pulse wave velocity (PWV), independently predicts cardiovascular event risk and is accelerated in obesity. Little is known regarding potential regional variations in arterial stiffening in obesity. We assessed aortic and femoral PWV with ex vivo analyses of femoral and coronary structure/function in a mouse model of western diet (WD; high‐fat/high‐sugar)‐induced obesity. WD increased aortic and femoral PWV. Ex vivo femoral artery analysis revealed a leftward shift in the strain‐stress relationship, increased modulus of elasticity, and decreased compliance indicative of increased stiffness following WD. Confocal and multiphoton fluorescence microscopy revealed that increased femoral stiffness involved decreased elastin/collagen ratio in WD. Analysis of the femoral internal elastic lamina (IEL) revealed reduced number and size of fenestrae with WD. Coronary artery stiffness/structure was unchanged by WD. Functionally, femoral, not coronary, arteries exhibited endothelial dysfunction while coronary, not femoral, arteries exhibited increased vasoconstrictor responsiveness. Overall, our data highlight important regional variations in arterial stiffening/dysfunction and highlight IEL fenestrae remodeling as a potential contributor to femoral artery stiffening in obesity.
Trial‐to‐Trial and Day‐to‐Day Variability in Forearm Blood Flow During Reactive Hyperemia
Authors: D'Urzo Katrina , Plotnick Meghan , Stuckless Troy , Pyke Kyra
Published: June 2021

Reactive hyperemia (RH) following the release of a brief limb occlusion is commonly used to assess resistance vessel function. The purpose of this study was to examine the impact of repeated trials on the within subject day‐to‐day variability of forearm blood flow during RH. Ten young, healthy, non‐smoking subjects (6 female, 4 male) were examined in the fasted state. Brachial artery diameter and blood velocity were assessed with Echo and Doppler ultrasound, respectively. Subjects visited the lab twice and performed four RH trials each visit. The RH protocol was performed on the left arm and included 5 minutes of forearm cuff occlusion at a pressure of 250 mmHg, followed by release. Within subjects trial‐to‐trial and day‐to‐day variability was assessed by the coefficient of variation (CV = (Standard Deviation/Mean) x 100). The Day‐to‐day CV was calculated using 1) Trial 1 from each day and 2) a 4‐Trial average. Peak forearm blood flow did not differ significantly between trials or days (p > 0.05). Within subject trial‐to‐trial variability was consistent between visits (CV, 9.39 ± 7.78% and 10.1 ± 3.19%; p = 0.737). The within subject day‐to‐day CV determined from the first trial on each day was not significantly different from the CV determined from the four trial average (CV, 14.9± 15.1% and 12.0± 9.62%; p = 0.240). In conclusion, averaging over repeated trials on each visit did not significantly reduce the day‐to‐day variability in peak reactive hyperemia blood flow.
Differences in the Responses to Chronic Rapamycin Treatment by Healthy and Insulin Resistant Rats.
Authors: Pulakat Lakshmi , Luck Christian , DeMarco Vincent , Lum‐Naihe Kelly , Mahmood Abuzar
Published: June 2021

The immunosuppressant rapamycin (Rap) inhibits mTOR Complex 1 and promotes longevity. However, Rap also induces type 2 diabetes (T2DM). Since DM is an independent predictor for cardiovascular disease, we investigated whether chronic Rap treatment that exacerbates diabetes modulates cardiac pathology differently in healthy and insulin resistant individuals. Young (8‐20 weeks) healthy Zucker lean (ZL) and insulin resistant Zucker obese (ZO) rats were subjected to 12‐week Rap treatment via subcutaneous implantation of Rap pellets delivering Rap at a concentration of 750μg/kg/day. Rap significantly suppressed body weight, heart weight, fasting plasma levels of cholesterol, triglycerides, and LDL in ZO rats, but worsened diabetes as indicated by severe hyperglycemia, polydipsia and polyuria (p<0.05). Echocardiography showed that 14‐week old ZO rats exhibited diastolic dysfunction evidenced by decreases in the tissue doppler E'/A' ratio, mitral inflow propagation velocity (Vp), and increases in LV filling pressure (E/E' and E/Vp ratios), isovolumic relaxation time (IVRT) and myocardial performance index (Tei index of global cardiac function) compared to age‐matched ZL rats(p<0.05). With the exception of IVRT, these abnormalities were improved in ZO rats treated for 6 weeks with Rap. However, an additional 6 weeks of Rap treatment reversed this effect. Histopathology showed that Rap induced significant cardiomyofibril disarray in both ZL and ZO rats (p<0.05), damaged the healthy circular morphology of pancreatic islets in ZL and ZO rats and reduced fibrosis in ZO rats, but not in ZL rats. Thus, the heart and pancreas of healthy and insulin resistant rats respond differently to chronic Rap treatment.
Gene Expression and Functional Studies of Janus Kinase 3 (JAK3) in Ovarian Granulosa Cells
Authors: Ndiaye Kalidou , Silversides David , Lussier Jacques
Published: June 2021

Janus kinase 3 (JAK3) belongs to a family of membrane‐associated intracellular non‐receptor tyrosine kinase proteins that mediate signals initiated by cytokine and growth factor receptors through the JAK‐STAT pathway. In contrast with the ubiquitous expression of other family members (JAK1, JAK2, and TYK2), JAK3 is predominantly expressed in hematopoietic cells. We previously identified JAK3 as a differentially expressed gene in granulosa cells (GC) of bovine dominant or preovulatory follicles. The objectives of the current study were to characterize the spatio‐temporal expression pattern of JAK3 in bovine ovarian follicles and to elucidate JAK3 mode of action in GC. GC were obtained from small follicles (SF: 2‐4 mm), dominant follicles (DF) at day 5 of the estrous cycle, and ovulatory follicles (OF) 24 hours (h) following injection of hCG. RT‐PCR analyses showed greatest expression of JAK3 in GC of DF, while the lowest expression was in GC of OF (P < 0.0001). Temporal expression analysis of JAK3 in follicular walls (granulosa and theca cells) of OF at 0, 6, 12, 18 and 24 h after hCG injection showed 5‐ and 20‐fold reduction at 12 and 24 h, respectively, following hCG injection as compared to 0 h (P < 0.05). Results of a yeast‐two‐hybrid screening of DF‐cDNAs library with JAK3 showed activation of the GAL4‐responsive reporters suggesting physical interactions between JAK3 and specific proteins in GC, which were confirmed by co‐immunoprecipitation analyses.This study reports for the first time that JAK3 is differentially expressed in GC of preovulatory follicles supporting a physiologically relevant role of JAK3 in follicular development, and provides insights into the mode of action and function of JAK3 in GC. (Research supported by NSERC of Canada grant # 104199 to JGL)
Protective effects of melatonin against ischemic neuronal damage in rats with transient focal cerebral ischemia
Authors: Won Jinyoung , Lee Seunghoon , Park Sookyoung , Hong Yonggeun
Published: June 2021

Background

The neurohormone melatonin may prevent neuronal cell death caused by neurodegenerative diseases. Purpose: Using a transient cerebral ischemic model (MCAO), we assessed the neuroprotective effect of melatonin in an ischemic region. Results: In this study of efficacy, experimental animals were subjected to MCAO for 60 min, and then given melatonin (injected at 5 mg/kg). The following three groups were formed: (1) control group (MCAO vehicle); (2) melatonin pre‐treatment group (injected intraperitoneally 5 min prior to MCAO and again 1 h post‐occlusion); and, (3) melatonin post‐treatment group (injected subcutaneously [twice daily] post‐MCAO onset for 3 days). In melatonin‐treated ischemic rats, brain infarction was reduced 3 days post‐MCAO surgery compared with controls, and physiological and neurological features differed, including molecular changes associated with cell death. Significant decreases in p53, Bax, caspase‐6, and LC3 expression levels were observed in the melatonin pre‐ and post‐treatment groups (P < 0.05). Suggestion: The brain morphological and molecular changes indicate that melatonin is associated with neurogenesis and confers protection against neuronal cell death.

Funding: 2012R1A1A2005089, 2013R1A2A2A01067169, KGM4611512, 2014R1A1A3051724
Variant Specific Cleavage of the Na+‐Ca2+ Exchanger NCX3 During Excitotoxicity
Authors: Michel Lauriane , Hoenderop Joost , Bindels René
Published: June 2021

Recent studies highlighted the crucial role of the Na+‐Ca2+ exchanger isoform 3, NCX3, during stress exposure, allowing for a significant Ca2+ entry in neuronal cells. Consequently, the hyperfunctionality of NCX3 triggered via its cleavage by the calpain protease, is considered to play a neuroprotective effect in numerous pathologies such as Alzheimer's disease and ischemia.NCX3 family contains three variants hypothesized to carry diverse capacity of exchange.

We aimed in dissecting the molecular mechanisms responsible for NCX3 cleavage during excitotoxicity.The capacity of exchange of each variant expressed in HEK293T cells was measured by recording single cell [Ca2+]i in response to Na+ removal. Additionally, the influence of calpain on NCX3 was investigated using overexpression of the endogeneous inhibitor, Calpastatin, and silencing of the calpain family.

We observed that the variants containing the exon B, NCX3‐B and NCX3‐BC, are predominantly expressed in the brain. Measurements of NCX3 revealed a significant decrease in the capacity of exchange of NCX3‐AC and NCX3‐BC during overexpression of Calpastatin. A similar effect was observed by silencing calpain‐1. Site‐directed mutagenesis was performed on a hypothesized cleavage site for calpain located in the exon C of NCX3. The mutation of L600 and L601, at the cleavage site, caused a loss of hyperfunctionality, as observed during the silencing of calpain‐1.

Calpain activity triggers an increase in the capacity of exchange of NCX3. However only the variants containing the exon C, NCX3‐AC and NCX3‐BC, are sensitive to calpain cleavage. The predominant expression of NCX3‐BC observed in the brain together with the identification of the cleavage site in NCX3 allows for potential drug design targeting these specific residues.
Expression of TRP Ion Channels in Cardiac Myocytes
Authors: Andrei Spencer , Bratz Ian , Damron Derek
Published: June 2021

The overall goal of this investigation was to determine the extent to which transient receptor potential (TRP) ion channels of the A1 and V1 subtypes are expressed in the murine heart and whether their expression patterns are altered in the setting of diabetes. TRP ion channels are well‐established ion channel receptors found throughout the body and have significant roles in regulation of the cardiovascular system. Surprisingly little is known about coexpression patterns of TRPA1 and TRPV1 in diabetic and healthy cardiac myocytes or the role they play in mediating intracellular events in the heart. Preliminary data from our lab shows for the first time that TRPA1 is expressed at the protein level in isolated mouse cardiac myocytes. Furthermore, we have found that TRPA1 and TRPV1 in cardiac myocytes show significant (P<0.05) dose‐dependent calcium responses when exposed to allyl isothiocyanate (AITC) and capsaicin, respectively. Moreover, the expression levels of these channels in diabetic cardiac myocytes are significantly lower (P<0.05) than those in healthy cardiac myocytes. In conclusion, TRPA1 and TRPV1 ion channels in cardiac myocytes respond to AITC and capsaicin, respectively, and are down‐regulated in diabetic cardiac myocytes.
Obesity in Saturated Fat Diet Does Not Alter the Proteins Involved in Myocardial Calcium Transit
Authors: de Deus Adriana , Vileigas Danielle , da Silva Danielle , Campos Dijon , Santana Paula , Oliveira Scarlet , Pagan Luana , Okoshi Marina , Cicogna Antonio
Published: June 2021

The aim of this study was to test the hypothesis that obesity by saturated high‐fat diet leads to changes in the expression and / or phosphorylation of proteins related to myocardial calcium handling. Wistar rats were divided into two groups: control (C, n = 18; saturated normolipidic diet) and obese (OB; n = 19; saturated high‐fat diet) for 30 weeks. Obesity was determined by adiposity index and comorbidities were evaluated. Cardiac morphological profile was estimated by post‐death macroscopic analysis. The protein expressions of calcium pump of the sarcoplasmic reticulum (SERCA2a), ryanodine receptor (RYR), calsequestrin (CSQ), phospholamban total (PLB), phospholamban serine 16 (PLB be 16), phospholamban threonine 17 (PLB thr 17), Na+/Ca2+ exchanger (NCX) and L‐type calcium channel (L channel) were performed by the method of Western Blot. In this study, the animals showed significant increase in adiposity index (p<0.001) and several comorbidities such as glucose intolerance (p<0.001), hyperleptinemia (p<0.001), hyperinsulinemia (p=0.03), hypertriglyceridemia (p=0.001), increased LDL (p=0.03) and NEFA (p=0.02) and hypertension (p=0.009). Macroscopic results showed no significant cardiac remodeling (p>0.05). The analysis of proteins related to the calcium handling showedno significant change: PLB (p=0.71), CSQ (p=0.62), SERCA2a (p= 0.61), PLB 17 Thr (p=0.58), NCX (p=0.47), PLB is 16 (p=0.42), RYR (p=0.19) and channel L (p=0.10). In conclusion, the results of this study show that obesity by saturated high‐fat diet does not promote significant changes in the levels of proteins related to myocardial calcium handling. Suport Fapesp.
Effects of Melatonin on Neural Reconstruction and Motor Recovery through Regulation of Endoplasmic Reticulum Stress Response and Autophagy in Spinal Cord Injured Animal
Authors: Jin Yunho , Park Sookyoung , Hong Yonggeun
Published: June 2021

Autophagy and endoplasmic reticulum (ER) stress response are known to cause improved motor function and reduced damage of axons after spinal cord injury. This study aims to elucidate the effects of melatonin treatment on neural reconstruction and motor recovery through regulation of ER stress response and autophagy.
Expression of neural and autophagic markers at mRNA level increased in injured experimental animals. And much higher increase of those markers was observed when treated with melatonin. Especially, at day 3, 28 after SCI, NG2 expression was increased at the injured site when treated with melatonin (p<.05). With melatonin treatment, LC3 expression was also increased at day 28 after surgery (p<.05). There was a tendency for spinal cord injured groups and melatonin‐treated groups to show increased ER stress response markers, when compared with the expression of non‐injured groups and non‐melatonin‐treated groups, respectively. Furthermore, more axonal sprouting and relatively intact morphology were observed in melatonin‐treated groups. Locomotor function was also improved when treated with melatonin.
In conclusion, melatonin treatment promoted the neural reconstruction of both neuronal and glial cells. It also reduced autophagic cell death and, consequently brought improved locomotor function.

Funding : 2012R1A1A2005089, 2013R1A2A2A01067169, KGM4611512, 2014R1A1A3051724
Exercise increases stem cell retention and exercise capacity post‐MI
Authors: Chirico Erica , Muthukumaran Geetha , Ding Dennis , Houser Steven , Starosta Tim , Mu Anbin , Margulies Kenneth , Libonati Joseph
Published: June 2021

Stem cell therapy for myocardial infarction (MI) has been shown to improve cardiac function and reduce infarct size. Exercise training, in the form of cardiac rehabilitation, is an essential part of patient care post‐MI. Hence, we tested the effects of acute and chronic aerobic exercise training on stem cell retention and cardiac remodeling post‐MI.

Small epicardial MIs were induced in 12 month old C57BL/6 mice via cryoinjury. 2‐weeks post MI, GFP+ bone marrow derived cells (BMC) were injected (tail vein) immediately after acute exercise (N=14) or sedentary conditions (N=14). A subset of mice continued a 5 week intervention of chronic treadmill exercise (10‐13 m/min; 45 mins/d; 4 d/wk; N=7) or remained sedentary (N=6). Exercise tolerance was assessed with a graded exercise test and cardiac function with echocardiography.

One bout of acute aerobic exercise increased GFP+ BMC retention in the infarcted zone of the heart by over 30% relative to sedentary conditions (P<0.05). This effect was not recapitulated with dobutamine infusions in resting animals. Chronic exercise training increased exercise capacity (95% vs sedentary, P<0.05) and cardiac mass (P<0.05), but did not alter LVEF or infarct size (P=NS). There was a significant inverse correlation between exercise tolerance and wet:dry lung weight (r=‐0.55, p = 0.02).

We conclude that acute aerobic exercise increases BMC retention in infarcted hearts. While chronic exercise training following stem cell therapy increased cardiac remodeling and exercise capacity, training did not alter the effects of BMC on resting cardiac function or infarct size.
Qualitative muscle mass index as the prognostic value of low muscle functions in the elderly.
Authors: Chang Jae Seung , Kim Hanul , Kim Tae‐Ho , Cha Seung‐Kuy , Kong In Deok
Published: June 2021

Sarcopenia is the gradual decreases of skeletal muscle mass and functions during aging. In general, muscle mass index as a predictor of sarcopenia should be well reflected by those of functions. However, the most widely used relative index that merely adjusted with height squared (ASM/ht2) may be insufficient to diagnose sarcopenia because of unconsidering the body compositional balance and estimating error in obese individuals. Therefore, we corrected ASM by indicators of obesity (BMI, waist circumference) and metabolic mass (BSA), which was named qualitative muscle mass index (QMI). Here, we performed Student's t‐test and ROC analysis to verify the adequacy of QMIs. Two hundred sixty two elderly participants were classified according to muscle functions. In muscle strength, all of QMIs were significantly lower in muscle weakness group compared to those of normal group regardless of gender, whereas there was no difference in ASM/ht2 between groups in men subjects. In muscle performance, ASM/BMI was significantly lower in low gait speed group compared to that of normal group regardless of gender, while there was no difference in ASM/ht2 between groups in both genders. Interestingly, unlike ASM/ht2, muscle weakness along with low gait speed can be dichotomized by ASM/BMI in both genders. The AUCs were 0.79 (p<0.05) for men and 0.75 (p<0.01) for women, and the cutoff values that maximized sensitivity and specificity were 0.84 kg/kg/m2 for men and 0.58 kg/kg/m2 for women, respectively. Taken together, these results implied that QMI such as ASM/BMI might be more suitable for predicting or reflecting functional status of skeletal muscle. Supported by Yonsei University Wonju College of Medicine Grant, YUWCM‐2013‐24
Angiopoietin‐1 Enhances Skeletal Muscle Regeneration in Mice
Authors: Danialou Gawiyou , Mofarrahi Mahroo , McClung Joseph , Kontos Christopher , Davis Elaine , Tappuni Bassman , Moroz Nicolay , Pickett Amy , Huck Laurent , Harel Sharon , Hussain Sabah
Published: June 2021

Activation of muscle progenitor cell myogenesis and endothelial cell (EC) angiogenesis (angio‐) is critical for the recovery of skeletal muscle (SM) from injury. Angiopoietin‐1 (Ang‐1) enhances angio‐ and SM satellite cell survival; however, its role in SM regeneration after injury is unknown. We assessed the effects of Ang‐1 on fiber regeneration (FR), myogenesis, and angio‐ in injured SM (tibialis anterior, TA) in mice.TA fiber injury was triggered by cardiotoxin (CTX). Endogenous Ang‐1 mRNA levels immediately decreased in response to CTX then increased over the course of two weeks. Ang‐1 protein was expressed in satellite cells, both in non‐injured and recovering TA. Four days after the initiation of injury, injection of adenoviral Ang‐1 into injured muscles resulted in significant increases in in situ TA contractility, muscle FR, and capillary density. In cultured human skeletal myoblasts, recombinant Ang‐1 protein increased survival, proliferation, migration, and differentiation into myotubes. We conclude that Ang‐1 strongly enhances SM regeneration in response to fiber injury and that this effect is mediated through induction of the myogenesis program in muscle progenitor cells and the angio‐ program in EC.
Hemodynamic Responses to Mild Warming during Simulated Hemorrhage
Authors: Poh Paula , Gagnon Daniel , Romero Steven , Petruzzello Steven , Convertino Victor , Crandall Craig
Published: June 2021

Warming a hemorrhaging victim is the standard of care. However, heating can be detrimental to the maintenance of arterial pressure and cerebral perfusion.

Purpose

To test the hypothesis that moderately warming a normothermic individual can be detrimental to the maintenance of arterial pressure and cerebral perfusion during a hemorrhagic insult.

Methods

Five men (age, 33 ± 9 y) underwent the following repeated measures design: following 15 min of supine rest, 10 min of 30 mmHg of lower body negative pressure (LBNP) was applied to simulate a moderate hemorrhagic challenge while subjects were normothermic. With LBNP continuing, subjects were exposed to warming (mean skin temperature (Tsk): 36.8 ± 0.4°C), skin surface cooling (Tsk: 29.7 ± 1.2°C), or thermoneutral (Tsk: 33.4 ± 0.4°C) for 40 min via water perfused suit.

Results

Interaction between the thermal perturbation and LBNP time did not reveal statistically distinguishable changes in blood pressure (P = 0.15), cardiac output (P = 0.14), stroke volume (P = 0.74) or cerebral perfusion (P = 0.13). However, the elevation in heart rate was greater (P = 0.01) during warming (22 ± 6 bpm) relative to cooling (7 ± 10 bpm) and thermoneutral (10 ± 6 bpm) conditions.

Conclusions

These preliminary data suggest that mild warming during the applied level of simulated hemorrhage does not compromise arterial blood pressure or cerebral perfusion. It remains unknown whether mild warming would be detrimental during a more profound hemorrhagic challenge.
Na+‐Cl‐ Cotransporter (NCC) is Differentially Regulated by Aldosterone in Early and late Distal Convoluted Tubule
Authors: Poulsen Søren , Christensen Birgitte
Published: June 2021

The Na+‐Cl‐ cotransporter (NCC) is expressed in renal distal convoluted tubule (DCT)1 and DCT2. Inherited NCC mutations lead to Gitelmans syndrome causing Na+ and K+ disturbances. NCC is stimulated by aldosterone, which is believed to depend upon the enzyme 11B‐hydroxysteroid dehydrogenase type 2 (11BHSD2). Because 11BHSD2 is expressed in DCT2 and not DCT1, it is widely believed that aldosterone stimulates NCC primarily in DCT2. However, the conjecture has to date not been directly tested. Hence, we hypothesized that the abundances of total NCC and NCC phosphorylated at T58 (pT58‐NCC; the phosphorylation increases NCC Na+ transport capacity) were stimulated by aldosterone in DCT2 but not in DCT1. B6/C57 male mice were administrated 100 µg aldosterone kg/24 h for 6 days. Western blotting confirmed that aldosterone stimulated total NCC and pT58‐NCC (P < 0.001). DCT1‐specific semi‐quantitative confocal fluorescence microscopy detected no effect of aldosterone on NCC and p58‐NCC abundances (P > 0.05). By contrast, NCC and pT58‐NCC were clearly stimulated in DCT2 and at the junction between DCT2 and CNT (P < 0.01). Collectively, our data suggest that aldosterone stimulates NCC and pT58‐NCC abundances in DCT2, whereas aldosterone has no/a minimal effect in DCT1. The data are consistent with what was previously suggested. Financial support was provided by MEMBRANES, Aarhus University, Denmark.
UF Center for Precollegiate Education and Training: University Partnerships for Teacher Professional Development
Authors: Darwiche Houda , Bokor Julie , Koroly Mary
Published: June 2021

The University of Florida Center for Precollegiate Education and Training (UF CPET) promotes the use of university resources for the preparation and enhancement of STEM teaching in secondary schools. UF CPET offers an array of teacher professional development programs, the two largest being the NIH SEPA‐funded Biomedical Explorations: Bench to Bedside. This innovative program integrates experiences from a summer institute into classroom action. Teachers work with science and education researchers to develop lessons and laboratory exercises that convey these content‐based principles in the context of career choices. During the school year, research proposals, resources, formal presentations, review of classroom outcomes and incentives for ongoing professional development provide continuing support to incorporate scientific processes, real‐world skills and enthusiasm for bioscience careers into classrooms. Continued support from UF CPET encourages science teachers' personal enrichment and professional advancement in biotechnology education and empowers them as agents of change in their classrooms and communities. Our newest program, the Summer Research Experience (SRE), a teacher‐scientist partnership model in which teacher fellows spend three weeks in an intensive residential research program. The primary outcome of this partnership program has been the development of our Biomedical Curriculum Series, comprised of thematic modules which are hands‐on and inquiry‐based, stress collaborative learning and biotechnology applications, as well as nature of science components and 21st century skills.
Diminazene, an ACE2 Activator Modulates Gut Microbiota and Provides Protection Against Pulmonary Hypertension
Authors: Shenoy Vinayak , Yang Tao , Rathinasabapathy Anandharajan , Horowitz Alana , Raizada Mohan , Katovich Michael
Published: June 2021

We have previously demonstrated that Diminazene aceturate (DIZE), an ACE2 activator attenuates pulmonary hypertension (PH). It is becoming clearer that disruption of the gut microbiome leads to metabolic and cardiovascular diseases. However, role of the gut microbiome in PH has not yet been studied. We hypothesized that PH is associated with microbial dysbiosis, and that treatment with DIZE restores the gut microbiome to provide cardiopulmonary protection. PH was induced in male Sprague Dawley rats by a single subcutaneous injection of monocrotaline (MCT, 50mg/Kg). A subset of MCT animals was treated daily with DIZE (15mg/kg, ip) for 4‐weeks, after which echocardiographic and hemodynamic measurements were performed, and fecal samples collected for microbiome analyses. MCT rats showed marked increase in right ventricular systolic pressure (RVSP; Control: 32+3 mmHg; MCT: 88+2 mmHg), along with the development of right ventricular hypertrophy (RVH; Control: 0.26+0.005; MCT: 0.61+0.01), which was associated with significant changes in the composition of the gut microbiota, and decreased levels of butyrate, a beneficial microbial metabolite. However, DIZE treatment restored the gut microbiome and increased butyrate levels to attenuate PH (RVSP; MCT+DIZE: 55+2mmHg) and associated cardiac hypertrophy (RVH; MCT+DIZE: 0.38+0.005). Collectively, our results demonstrate that PH is associated with microbial dysbiosis and that DIZE treatment modulates the gut microbiome to provide cardiopulmonary protection.
Adipose Stem Cells attenuates Bleomycin induced Pulmonary Fibrosis
Authors: Rathinasabapathy Anandharajan , Shenoy Vinayak , Horowitz Alana , Guzzo Dominic , Jaekel Sina , Raizada Mohan , Katovich Michael
Published: June 2021

Pulmonary Fibrosis (PF), a progressive lung disease, resulting in extensive tissue modeling ultimately leads to mortality. Existing therapy does not curtail the rate of mortality. Here, the protective role of adipose stem cell (ASC) in PF was studied. Bleomycin (Bleo) was injected into 8‐weeks old male SD rats to induce PF. Post 3 days of Bleo challenge, 1X106 ASC were administered through the jugular vein. After 2 weeks of Bleo injection, Picro Sirius and H&E staining demonstrated a significant lung tissue remodeling and fibrosis. Further, ventricular hemodynamics of Bleo‐treated animals was significantly dysregulated, RVSP (28.88±1.39 vs 45.02±3.62 mmHg) and right ventricular hypertrophy (RVH; 0.26±0.02 vs 0.39±0.04). Echocardiography (ECHO) results demonstrated that the ratio of RV/LV (End‐Diastolic Area; 0.31±0.02 vs 0.63±0.03 %) and (Ejection Fraction; 1.39±0.03 vs 1.90±0.06 %) was significantly dysregulated in PF. ASC therapy significantly attenuated the tissue remodeling and fibrosis with a concomitant reduction in RVSP (33.29±2.32) and RVH (0.32±0.03). In addition, ASC therapy normalized all the ECHO parameters. In a separate study, ASC was administered after 7 days of bleo injections. Similar to day 3, day 7 therapy also prevented the progression of PF. Collectively, our data demonstrate that ASC based cell‐therapy arrested PF and associated cardiac remodeling, suggesting, ASC intervention could be a potential therapeutic strategy for the treatment of PF.
Investigating Social Jet Lag in the 6th Grade, a 2015 PhUn Week Activity to Introduce Circadian Physiology in Middle School
Authors: Solocinski Kristen , Gumz Michelle
Published: June 2021

Dr. Gumz and Ms. Solocinski visited Westwood Middle School in Gainesville, FL to introduce 6th graders to the concept of circadian physiology. They gave a 15 minute PowerPoint presentation to 14 different classes with more than 200 students to introduce physiology and circadian biology. A timeline was used to demonstrate that investigation of circadian rhythms has been taking place for centuries. The students learned that organisms ranging from bread mold to flies to humans rely on an internal circadian clock to adapt to their environment. Consequences of disrupted rhythms in mice, middle school students, medical doctors, and football players were discussed. The students were given parental consent forms and questionnaires to participate in an IRB‐approved study investigating whether social jet lag occurs in the 6th grade. Social jet lag occurs when an individual's internal body clock is out of sync with their daily schedule, and it often happens when a person follows a different sleep/wake schedule on free days versus rest days. Preliminary results indicated that 6th graders were significantly more tired on school days early in the week relative to rest days. Conversely, significant differences were not observed between school days later in the week relative to rest days. These results suggest that 6th graders gradually adjust to a school day schedule as the week progresses but they may experience social jet lag from following a different sleep/wake schedule on the weekend.
Aged Female HV1‐/‐ DAHL Salt‐Sensitive Rats Develop a Pro‐Inflammatory T‐Cell Profile
Authors: Ralph Erica , Sullivan Jennifer , O'Connor Paul
Published: June 2021

Th17 cells are pro‐inflammatory cells that have been implicated in the pathogenesis of several autoimmune diseases and more recently linked to the progression of hypertension and related end‐organ damage. Hv1 is a voltage‐gated H+ channel highly expressed in immune cells, including T cells. Hv1‐knockout mice have been reported to develop an autoimmune phenotype, including greater activation of circulating CD4+ T‐cells and development of nephritis in aged mice, which is more pronounced in females. We have recently developed a Hv1‐/‐ rat on the Dahl salt‐sensitive rat (SS) genetic background. The goal of this study was to determine whether T‐cells are activated in male and female rats lacking Hv1 and whether this is associated with alterations in blood pressure and/or renal injury. Flow cytometry analysis did not identify a difference in CD4+ T‐cells or Th17 cells in whole blood from 12 week old female SS and Hv1‐/‐ SS rats fed either a low (0.4%) or high (8%) NaCl diet for 14 days prior to sacrifice (TABLE). The number of circulating pro‐inflammatory T‐cells was significantly increased in aged Hv1‐/‐ rats, with T‐cell activation being more pronounced in females (TABLE; p=0.005). Despite significantly more circulating Th17 cells in aged female Hv1‐/‐ rats, blood pressure (telemetry) was not different between the sexes at 40‐42 weeks of age (162±7mmHg; n=5 and 158±8mmHg; n=6 in females and males, respectively) and renal injury was significantly worse in male Hv1‐/‐ rats (proteinuria 61±24mg/day in females vs 165±32mg/day in males; p=0.014). We conclude that aged female Hv1‐/‐ SS rats develop a more activated circulating inflammatory T‐cell profile compared to males but that this is not associated with higher blood pressure or worse renal injury.

12 wk WTFemale0.4% LS
12 wk WTfemale 8%HS
12 wk KO Female 0.4% LS
12 wk KO female 8% HS
42 wk KO female 0.4% LS
42 wkKO male0.4% LS

CD4+ cells (% CD3+)
38±1
50±3
37±2
40±4
70±2
52±1

Th17 cells (% CD3+CD4+)
21±5
27±7
32±2
24±8
55±1
43±1
Genomic Editing of Stem Cells for Modeling and Therapy of Genetic Diseases
Authors: Menon Tushar , Firth Amy , Scripture‐Adams Deirdre , Parker Greg , Gilmore William , Lewis Benjamin , Qualls Susan , Zack Jerome , Verma Inder
Published: June 2021

The application of advanced genome editing technologies, when combined with induced pluripotent stem cells (iPSC), presents a unique opportunity to develop unprecedented patient‐specific in vitro models of disease‐in‐a‐dish that can be used for the development of more effective and universal stem cell therapies. Towards this aim, we have corrected SCID‐X1 patient‐derived iPSC using TALENs, resulting in the rescue of defective IL2RG expression and in the recovered generation of lymphoid cells derived from these iPSC. We have also corrected the common ΔF508 mutation of CFTR in cystic fibrosis patient‐derived iPSC using a novel, efficient, footprint‐free CRISPR‐mediated approach, and shown the subsequent functional recovery of CFTR function in airway epithelium derived from the corrected iPSC.

However, the inability to derive truly transplantable cell types from iPSC limits the long‐term clinical and therapeutic potential of this approach. To address this we have carried out direct CRISPR‐mediated gene correction of CD34+ hematopoietic stem cells (HSC) from the FoxP3 mutant scurfy (sf) NOD mouse, which is defective for the development of regulatory T‐cells. These directly gene‐edited FoxP3sf HSC can then be evaluated for their potential for long‐term engraftment and regeneration of regulatory T‐cells by transplantation into lethally irradiated recipient mice. The ultimate goal is to establish novel pre‐clinical models for stem cell‐based therapy for a variety of genetic disorders.
Evaluation of the Cytotoxicity and Genotoxicity of AlkaloidRich and Alkaloid‐Free Aqueous Extracts of Rhazya stricta Leaves
Authors: Yaghmoor Soonham , Baeshen1 Nabih , Kumosani Taha
Published: June 2021

Rhazya stricta (Apocynaceae) is popularly known as “harmal” and is used in folk medicine in the form of decoctions to treat illnesses that include diabetes mellitus, fever, sore throat, inflammatory conditions, and helminthiasis. Despite its widespread therapeutic use, there is a lack of data regarding its in vivo genotoxic effects. Therefore, in this study we evaluated the possible genotoxic and clastogenic effects of R. stricta extracts in Rattus norvegicus rats. Three prepared Rhazya extracts (whole aqueous, alkaloid, and nonalkaloid) were independently administered to rats by oral gavage. At the indicated time periods, blood samples were drawn from control and treated animals and leukocytes were isolated and subjected to random amplified polymorphic DNA (RAPD)‐PCR and comet, micronucleus, chromosomal aberration, and mitotic index assays. The results showed that whole aqueous and alkaloid, but not nonalkaloid, extracts of R. stricta altered the genomic RAPD profile, induced significant DNA damage, significantly increased micronuclei formation, induced chromosomal aberrations, and decreased the mitotic index at all tested doses. Under our experimental conditions, the data obtained suggest that oral administration of R. stricta extracts causes genotoxicity and clastogenicity in rat leukocytes. The significance of these findings is discussed in light of the use of these plants as therapeutic agents.
Probing the necessity of the lipoate cofactor in Plasmodium
Authors: Jhun Hugo , Spalding Maroya , Sinnis Photini , Prigge Sean
Published: June 2021

Lipoate is an organosulfur cofactor that participates in several, well‐conserved metabolic pathways in malaria parasites. The mitochondrial proteins of Plasmodium are lipoylated through the uptake of lipoate from the red blood cell, where it is then imported into the mitochondrion and ligated to three proteins: the mitochondrial pyruvate dehydrogenase (mPDH), the alpha‐ketoglutarate dehydrogenase (KDH), and the H protein of the glycine cleavage system. When parasites are treated with a lipoate analog, (8‐bromooctanoate), parasite growth is significantly decreased, with concomitant decrease in lipoylation; this inhibition is reversed with the addition of supplemental lipoate. Expression of an exogenous, bacterial lipoamidase, which can cleave lipoate from lipoylated proteins, is not tolerated in the mitochondrion of the parasite, while it is tolerated elsewhere in the parasite. This body of evidence suggests that lipoylation, and not just lipoate, is crucial for parasite growth. Gene disruption in the human parasite, P.falciparum, and gene knockout in the mouse parasite, P.berghei, suggest that the PDH and KDH may not be individually essential for parasite growth. Thus, the H protein may be the only essential lipoylated protein in the parasite. In parallel, site directed mutagenesis has been used to strongly attenuate catalytic activity of the bacterial lipoamidase. Mutant lipoamidase enzymes will be expressed in both human and murine malaria parasites in an attempt to obtain intermediate phenotypes. Analysis of these parasites will identify the essential biochemical pathway that is responsible for lipoate auxotrophy in malaria parasites. Research support is provided by funding from the NIAID, the JHMRI and the Sommer Scholarship.