bluuebunny/crossref_metadata_2025 huggingface dataset:
Inoculation of purified antibodies reproduces antiphospholipid syndrome in mice
Authors: Cañelas Adriana , Silva Guillermo B , Acosta J M , Borbore A , Greco M , Larrea Claudio
Published: June 2021

Increases in antiphospholipid (aPL) antibodies (abs), including anticardiolipins (aCL) are associated with thromboembolic disease (TED) and autoimmune hemolytic anemia (AHA). Up to date, there is no animal model that reproduces similar traits of these diseases. The aim of this study was to develop an animal model that reproduces the thrombocytopenia and deep vein thrombosis (DVT) observed in patients with TED as well as the decrease in hematocrit (HTO) observed in AHA patients. To do this, we first collected serum from patients with TED and AHA and from healthy individuals as control. Presence of ACL was confirmed by ELISA in serum from patients but not from control. Then, IgG's purified in a commercial column and 8 weeks‐old Balb/c mice were inoculated. HTO and platelet count was determined before inoculation and 1, 2 and 3 days after. Thrombocytopenia was found in inoculated mice with serum from TED patients after 2 days compared to control (207 ± 20 vs. 395 ± 31 [x103] plts/mm3; p = 0.02; n = 8). Inflammation and necrosis were observed in limbs of these mice. HTO significantly decreased in mice inoculated with purified Abs from AHA patients compared to control (p < 0.001; n = 8). Platelet count and HTO in the control group remained unchanged and showed no signs of necrosis and/or inflammation. We conclude that inoculation with purified Abs from TED and AHA patients reproduces some of characteristics of aPL syndrome in mice.
ED‐1 is a marker for activated macrophages and subclinical graft versus host disease in vascularized stem cell transplants
Authors: Brown Russell , Lefebvre Daniel , Tai Chai , Matthews Martha , Strande Louise , Eydelman Riva , Hewitt Charles W.
Published: June 2021

Acute and chronic graft‐versus‐host disease (GVHD) is a major complication of bone marrow transplantation (BMT). Overt histopathological findings of GVHD are well documented. However, histopathology of subclinical GVHD is uncertain. We are studying a new type of BMT that can facilitate tolerance induction without GVHD. We hypothesized that subclinical GVHD may be induced. The model is known as a vascularized bone marrow transplant (VBMT).

Lewis‐Brown‐Norway (LBN) rats radiation. Rats then received either a cellular (cBMT, n=5) or VBMT (n=4). After 110 days, splenic histopathology was assessed by H&E staining and digital image analysis.Then splenic specimens were studied using Immunohistochemical staining for ED‐1 macrophage cell surface antigen.

Digital image analysis revealed very little hemosiderin present in the control spleens (mean ISI 0.86) and a large amount of hemosiderin in the cBMT spleens (mean ISI 11.75). The VBMT had an intermediate level of hemosiderin (mean ISI 8.27). All groups were significantly different (p<0.05). Qualitatively, it was noted that increased amounts of ED‐1 positive macrophages were present in cBMT spleens and VBMT spleens undergoing subclinical GVHD, compared to normal spleens.

Hemosiderin laden and activated macrophages may represent markers for sub‐clinical GVHD due to red blood cell destruction through opsonization associated with graft versus host disease.
Role of mitochondria in flow‐induced dilation of human adipose arterioles from subjects with and without coronary artery disease
Authors: Zinkevich Natalya Sergeevna , Wittenburg April L , Gutterman David D
Published: June 2021

Background

Flow‐induced dilation (FID) is an important physiological stimulus in regulating tissue blood flow. FID is typically mediated by endogenous vasodilators including nitric oxide (NO) and prostacyclin. In humans with coronary artery disease (CAD), FID occurs but is not mediated by NO; rather hydrogen peroxide (H2O2) is responsible. In the coronary circulation H2O2 derives from the mitochondria, but it is not known if this is a generalized process that also involves adipose arterioles. We examined the hypothesis that the mitochondrial electron transport chain critically contributes to FID in human adipose arterioles.

Methods

Visceral adipose arterioles (~150 μm ID) obtained at surgery from patients with or without CAD were cannulated and pressurized (60 mmHg) for videomicroscopy. After constriction with endothelin‐1, vasomotor responses to flow were evaluated in the presence and absence of the rotenone (1microM), a mitochondrial complex I inhibitor. At the end of each experiment, papaverine (0.1 mM) was added to obtain the maximal arteriolar diameter and assess non‐specific effects of rotenone.

Results

FID was reduced by rotenone in adipose arterioles from patients with CAD (%max dilation: 33±10 vs. 73±10%). In contrast, rotenone had no effect on FID arterioles from patients without CAD (%max dilation: 61±9 vs. 65±6%) or on the dilation to papaverine in either group.

Conclusions

We speculate that in patients with but not in those without CAD FID requires an intact proximal mitochondrial electron transport. This is a general response seen in multiple vascular beds.
Chronic Left‐Ventricular Dysfunction Increases Oxidative Stress in Skeletal Muscle: Potential Mechanism of Cardiac Cachexia
Authors: Semprun‐Prieto Laura , Sukhanov Sergiy , Bhutto Junaid , Titterington Jane , Delafontaine Patrick
Published: June 2021

Skeletal muscle (SM) atrophy during congestive heart failure is a process associated with a poor prognosis whose pathogenesis remains poorly understood. To determine if there is an increase in oxidative stress in SM atrophy induced by congestive heart failure, we used a murine model of chronic left‐ventricular dysfunction (CLVD) provoked by myocardial infarction. The left coronary artery was ligated in 8‐12 week old FVB mice (LAD, n=7) and sham‐operated mice were used as controls (ctr, n=12). LAD‐ligated mice had significant left‐ventricular dysfunction at 12 weeks by echocardiography (% FS, ctr, 47.24 ± 4.4% vs. LAD, 28.6 ± 4.7%; p<0.05, LVDs, ctr, 4.4 ± 0.4mm vs. LAD, 3.6 ± 0.1mm, p<0.01; LVDd, control 1.9 ± 0.1mm vs. LAD, 3.1 ± 0.5mm, p<0.01). In addition, LAD ligation produced significant SM atrophy as evidenced by a reduced body weight (ctr, 29.61 ± 0.37g vs. LAD, 27.76 ± 0.68g, p<0.05), SM weight (gastrocnemius, GM) (ctr, 133.9 ± 2.2mg vs. LAD, 126.3 ± 1.7mg, p<0.05), GM fiber cross‐sectional area (control 1292.2 ± 70.1 μm2, n=5, vs. LAD, 934.1 ± 10.7 μm2, n=2, p<0.05), and a significant shift in the myofiber size distribution towards smaller size fibers (p<0.01). SM wasting was associated with a 51% increase in muscle superoxide levels as quantified by staining GM cross‐sections with superoxide‐sensitive dye dihydroethidium (relative DHE fluorescence, ctr, 18.20 ± 2.9 vs. LAD, 27.40 ± 5.4, p<0.05). In summary, CLVD produces an increase in oxidative stress that is associated with progressive muscle atrophy.
Interleukin (IL)‐1 regulates ozone‐induced nerve growth factor (NGF) release in bronchoalveolar lavage fluid (BALF) in mice
Authors: Barker Joshua , Wu Zhongxin , Dey Richard
Published: June 2021

Our previous studies showed that both IL‐1 and NGF increase synthesis of substance P (SP) in airway neurons after either direct application or ozone exposure. We hypothesize that NGF mediates IL‐1 effects on SP, similar to the pathway described for sympathetic neurons in culture. The current study specifically focuses on the effect of IL‐1 on NGF levels in mice BALF. Three different experimental groups of adult mice were exposed to 2 ppm ozone for three hours while a control group was exposed to filtered air. The three experimental groups were 1) intratracheal (i.t.) instillation of IL‐1 receptor antagonist (IL‐1Ra) before ozone exposure; 2) i.t. instillation of saline before exposure; and 3) ozone exposure with no i.t. instillation. The following day, BALF was collected and NGF concentration was determined using Enzyme‐Linked ImmunoSorbent Assay (ELISA). The results showed ozone exposure alone or after saline instillation significantly increased the NGF level (3230 ng/ml ± 1039 and 2710 ng/ml ± 773 respectively) compared with the filtered air control group (1426 ng/ml ± 694). Pretreatment with IL‐1Ra attenuated the ozone‐induced increase in NGF levels (1045 ng/ml ± 51 units). These data indicate that IL‐1 regulates the ozone‐induced increase in NGF release in mice. Funded by NIH HL 35812.
High Salt Exacerbates Proteinuria in Chronic Angiotensin‐II Infused Rats.
Authors: Lowenburg Benjamin M , Planchard Jeffrey A , Martin Victoria L , Davis Porcha D , Botros Fady T , Mitchell Kenneth D , Navar L Gabriel , Prieto Minolfa C
Published: June 2021

This study examined the effect of a high salt (HS) diet on systolic blood pressure (SBP) and proteinuria in chronic Ang II‐infused hypertensive rats with and without RAS blockade with an Ang II type I receptor blocker, losartan (LOS). Male Sprague‐Dawley rats divided into four groups: 1) Sham+HS [n=5]; 2) Ang II [n=3]; 3) AngII+HS [n=5]; 4) Ang II+HS+LOS [n=5] were infused with Ang II (80 ng/min) for 14 days, fed with HS diet (8% NaCl) and treated with LOS (30 mg/L, drinking water). SBP progressively increased in Ang II and Ang II+HS rats up to 228±9mmHg and 228±10mmHg, respectively, compared to Sham+HS (128±7mmHg). Losartan attenuated the increases in SBP during the two‐weeks of treatment (144±9mmHg). Rats receiving Ang II+HS showed marked proteinuria measured in 24h‐urine collections (79±26mg/day) which was greater than in the Ang II group. Proteinuria decreased in the Ang II+HS+LOS, but not to levels of Sham+HS (29±2mg/day vs. 18±1mg/day), indicating a partial beneficial effect of LOS on proteinuria. The lack of difference between SBP in rats with Ang II‐induced hypertension and those that also received HS suggest that HS does not exert an additive effect on SBP. However, the presence of marked proteinuria in Ang II+HS rats indicates that HS might contribute to glomerular kidney damage independently of SBP and Ang II effects suggesting a direct action on glomerular protein barrier.

Support from NIH and Merck & Co., Inc.
Impaired pressure‐natriuresis relationship precedes the development of hypertension in Cyp1a1‐Ren‐2 transgenic rats
Authors: Cervenka Ludek , Thumová Monika , Husková Zuzana , Vanecková Ivana
Published: June 2021

Objective

The present study was performed to characterize the autoregulatory efficiency of renal blood flow (RBF) and glomerular filtration rate (GFR) and the pressure‐natriuresis relationship in transgenic rats with inducible hypertension (Cyp1a1‐Ren‐2 rats).

Methods

The renin gene was induced in Cyp1a1‐Ren‐2 rats trough dietary administration of the natural xenobiotic indole‐3‐carbinol (I3C, 0.3 %) for 12 hours. Non‐induced rats served as controls. Anesthetized rats were prepared for renal function studies and an aortic clamp was placed on the aorta to regulate the level of renal arterial pressure. ANG II levels were measured by radioimmunoassay.

Results

Administration of I3C resulted in progressive increases in ANG II levels as compared with non‐induced rats. I3C‐induction for 12 hours did not cause significant changes in blood pressure as compared with non‐induced rats. 12 hours I3C‐induction caused an impairment of the autoregulatory efficiency of RBF and GFR and of the pressure‐natriuresis relationship as compared with non‐induced rats.

Conclusions

Our findings indicate that an impairment of the pressure‐natriuresis mechanism precedes the development of ANG II‐dependent hypertension in Cyp1a1‐Ren‐2 transgenic rats.
Stress induced activation of brain regions in genetically hypertensive mice
Authors: Davern Pamela , Head Geoffrey
Published: June 2021

The high blood pressure (BPH) strain of "Schlager" mice have greater arousal associated rises in blood pressure compared with normotensive mice (BPN). To elucidate whether this is due to a neurogenic mechanism, we examined brain regions activated by acute aversive stress that may contribute to the hypertension. BPN and BPH mice were implanted with telemetry devices to measure cardiovascular variables at rest and throughout a 1 hr cage swap stress. Neuronal activation was detected using c‐Fos‐immunohistochemistry. Greater resting mean arterial pressure (MAP) was recorded in BPH mice (102±2 mmHg; n = 5) than in BPN mice (86±1 mmHg; n = 7). Heart rate (HR) levels were also elevated in BPH mice (438±11 bpm) compared with BPN mice (338±5 bpm). Cage swap increased MAP more in BPH compared to BPN mice (+41±2 vs +31±1 mmHg, P < 0.001), as did activity (+6.3±0.5 vs +2.6±0.2 units, P < 0.001). By contrast, HR increased less in BPH mice (+275±13 vs +356±15 bpm, P < 0.001). Exposure to acute stress induced 33% greater neuronal activation in the paraventricular nucleus (P < 0.05) and 27% greater in the dorsomedial hypothalamus (P < 0.001) in BPH (n = 3) compared to BPN mice (n = 3). A relatively "natural" arousal response induces a markedly greater activation of brain regions important for regulating cardiovascular autonomic function. The greater pressor response to stress suggests a central mechanism may be contributing to the hypertension.
ThermoTRP channels are upregulated during incubation in the skin of the brood patch in junglefowl hens
Authors: Altimiras Jordi , Jafari Shadi
Published: June 2021

Egg incubation in birds relies on the supply of heat through a specialized skin region, the brood patch, which develops seasonally after defeathering, epidermal hyperplasia and vascularisation of ventral skin regions. The brood patch is highly sensitive to temperature and, unlike other vascular beds, responds to local cooling with vasodilation (cold‐induced vasodilation) but the molecular mechanisms leading to the differential vascular response are largerly unknown. We hypothesized that thermoTRP in the avian brood patch could serve two complementary functions: 1) as temperature sensors and 2) as local regulators of vascular resistance. In skin RNA extracts we showed the presence of TRPV1, TRPV3 and TRPM8 but not TRPA1 using RT‐PCR techniques and confirmed the upregulation of TRPV3 but not TRPV1 in broody hens compared to non‐broody hens using qPCR techniques. Supported by a research grant from the Swedish Research Council (VR).
Role of the lateral prefrontal cortex in cardiovascular responses to acute restraint in rats
Authors: Alves Fernando Henrique Ferrari , Crestani Carlos Cesar , Corrêa Fernando Morgan de Aguiar
Published: June 2021

Objective

Previous works have demonstrated the participation of the lateral prefrontal cortex (LPC) in cardiovascular modulation in stress situations. However, these works was made which lesions or microinjection of the lidocaine, which are non selective methods that blockade or destroyed both, passenger fibres and synapses. To investigate the real participation of (LPC) in the cardiovascular modulation we used CoCl2 that is selectively blocks synapses. Thus the aim of present work was to study the participation of LPC in the modulation of cardiovascular system during acute stress.

Methods

Male Wistar rats had guide cannulas bilaterally implanted in the LPC. One catheter was implanted in the femoral artery for mean arterial pressure (MAP) and heart rate (HR) recording. Acute stress was induced by putting animals in a small plastic cylindrical restraining tube during 60 min.

Results

Microinjection of cobalt in the LPC caused no changes in MAP or HR, which were 100±1 mmHg and 352±11 bpm, n=6. Cobalt treatment significantly decrease response to restraint‐evoked HR and BP, when compared with aCSF‐treated animals (ΔMAP, F=1.3, P=0.03 and ΔHR, F=2.1, P<0.000; two‐way ANOVA.

Conclusion

Our data indicate that LPC is involved in the modulation of the cardiovascular system during acute stress.

Financial support

FAEPA, CNPq
Nevada state policies advance collaborations and efforts to assess nutritional health with body mass indices in children in public schools.
Authors: Meacham Susan L. , Bungum Nicole , Taylor Diana , Hansen Alicia , Mills Ruth Annette , Roller Christopher , Paulsen Barbara
Published: June 2021

Adult obesity increased in 37 states in the US in 2007. Obesity is associated with much comorbidity with an estimated $337 mil in medical expenses in NV (2003). Over the past 30 yrs the occurrence of overweight in children in the US has doubled and is considered the most prevalent nutritional disorder of US children and adolescents. NV has taken bold measures and was ranked 2nd and 4th in 2006 and 2007 for passing policies to improve school food environments. NV educated 426,436 pupils through the public school system last year. In 2007 NV passed legislation to randomly sample public school children in representative schools for body heights and weights to calculate body mass indices. In most districts school nurses weighed all children in 4th, 7th, and 10th grades. Two large districts randomly sampled students to achieve an 95% confidence level with +/‐ 3.5% accuracy. With 12 of 17 districts reporting a minimum overall state collection rate of 90% was achieved. A state wide collaboration was launched to support this 3 yr data collection. Members of county and state agencies, universities, and community non‐profit organizations united to request ongoing sampling, beyond 2010. The collective efforts, with assistance from the Division of Health, provided the first state‐wide data on children's nutritional health. The partners also acknowledge the dedication of the nursing profession for their commitment to action for improving the health of children in NV with no dedicated funding.
Challenges in promoting fruits and vegetables for obesity prevention
Authors: McCabe‐Sellers Beverly , Lovera Dalia , Onufrak Steve , Bogle Margaret
Published: June 2021

The rural states of the Lower Mississippi Delta lead the nation in rising prevalence of obesity in adults and children. The American Academy of Pediatrics recommends promoting fruit and vegetables (F&V) to children as a means of lowering the risks of obesity. This paper describes challenges found in F&V promotion to improve overall diet quality and prevent obesity.. The willingness to try new fruits and vegetables was promoted through a fresh F&V snack feeding program in a rural summer day camp for three years. Children were more willing to try the snacks than initially reported. Produce was ordered from a leading national food distributor for a weekly delivery of fresh produce with canned fruits as backup. Quality in year 1 was very good with no return of produce . In year 2 quality of fresh produce was generally good with 1 return.. In year 3 with the sharp rise in fuel and food costs, quality of both fresh and canned fruits and vegetables dropped dramatically. Over one in four cans of arrived dented. Replacement of fresh vegetables is not easily done with no supermarket within 20 miles. Fresh fruit arrivied semi‐frozen one time and overripe/crushed another time. Fresh vegetables and fruits deteriorated with 2‐3 days of delivery. Rising cost of foods presented another challenge. Reliance on obtaining quality fresh produce in rural areas is questionable for both research studies and lifestyle changes. Availability and quality of fresh produce in rural, low‐income area present public health challenges to overcome if optimal nutrition and healthy weight are to be achieved..
Central amylin causes more potent anorexigenic effects in chicks selected for low rather than high body weight
Authors: Prall Brian Christopher , Siegel Paul , Cline Mark Andrew
Published: June 2021

Amylin is a 37 residue peptide that is co‐released with insulin from the pancreas and potently reduces appetite. In the present study, we tested the effects of intracerebroventricularly (ICV) injected amylin in chicken models of hypo‐ and hyper‐phagia. These chicken models have been divergently selected for low (LWS) or high (HWS) body weight for nearly 50 generations and contain anorexic and obese individuals. In experiment one, the anorexigenic effects of amylin were more potent in line LWS, than in line HWS. Chicks in line LWS responded to all doses of amylin tested (128, 256 or 512 pmol) with reduced food intake during the 180 min observation period, whereas food intake was only reduced in HWS chicks treated with 256 and 512 pmol. Line HWS chicks treated with all doses of amylin reduced water intake, but water intake was not affected in line LWS. In experiment two, the magnitude of decreased food pecks after ICV amylin (256 nmol) was greater in line HWS than LWS. Other behaviors including exploratory pecking, jumps, escape attempts, drinks, defecations, and time spent standing, perching, sitting or preening were not affected by amylin treatment. Therefore, amylin does not appear to be associated with behaviors that may be competitive with appetite. These results may provide insights into physiological mechanisms associated with inherited body weight dysfunctions in a variety of species, including humans.
Upregulation of Guanylyl Cyclase/Natriuretic Peptide Receptor‐A Gene Expression by All‐trans Retinoic Acid Signaling
Authors: Kumar Prerna , Bolden Gevoni , Pandey Kailash N.
Published: June 2021

Atrial natriuretic peptide (ANP) exerts its physiological effects by binding to guanylyl cyclase/natriuretic peptide receptor‐A (GC‐A/NPRA), which generates the second messenger cGMP. The present study was aimed at gaining insight into the function of all‐trans retinoic acid (ATRA) in the regulation of Npr1 (coding for GC‐A/NPRA) gene transcription and expression. Npr1 gene promoter‐reporter deletion constructs were transiently transfected in cultured mouse mesangial cells (MMCs) and rat thoracic aortic smooth muscle cells (RTASMCs) and transcriptional activity was measured by dual luciferase assay. The results demonstrated that ATRA enhances Npr1 promoter activity by more than 6‐fold and induces NPRA mRNA levels in a dose‐ and time‐dependent manner. The effect of ATRA was mimicked by RA receptor agonist TTNPB, which enhanced the Npr1 gene transcription by 5‐fold. ATRA also increased Ets‐1 expression and enhanced its in vivo binding to Npr1 promoter as confirmed by chromatin immunoprecipitation assay. The results showed that ATRA significantly enhanced NPRA protein expression, its guanylyl cyclase activity, and ANP‐dependent intracellular accumulation of second messenger cGMP. The results demonstrate that retinoic acid signaling enhances Npr1 gene transcription and expression, which will have important implications in hypertension and cardiovascular regulation and prevention of high blood pressure and cardiac remodeling.
Coronary flow velocity reserve is reduced in mice with atherosclerosis, pressure overload hypertrophy, and coronary occlusion
Authors: Hartley Craig J. , Reddy Anilkumar K. , Entman Mark L. , Michael Lloyd H. , Taffet George E.
Published: June 2021

In man, coronary flow reserve (CFR) is reduced by most forms of heart disease, but it is not known how heart diseases modeled in mice alter CFR. We used Doppler ultrasound to measure left main coronary flow velocity (CFV) noninvasively in: 20 2‐yr old ApoE‐/‐ (atherosclerotic) mice, 10 age‐matched wild‐type (WT) controls, 10 6‐wk old WT mice, and 13 3‐mo old WT mice before and 21 days after transverse aortic banding (TAB) or LAD coronary artery occlusion (OCCL). All mice were C57BL6. We measured CFV and heart rate (HR) at baseline (B) and hyperemia (H) induced by changing the level of isoflurane gas anesthesia from 1 to 2.5%, and estimated CFR as H/B. Baseline HR and CFV in WT mice were 434±20 b/min and 16±3 cm/s (mean±SEM), and CFR was 2.4±0.1 (6‐wk), 3.2±0.3 (3‐mo), and 3.6±0.2 (2‐yr). For the disease models, CFR was: 2.5±0.2 (ApoE‐/‐), 1.1±0.1 (TAB), and 2.0±0.1 (OCCL), all P<0.05 versus control or pre‐intervention. The average change in HR at H versus B was 1.05±0.3. We found that isoflurane gas is a convenient and noninvasive coronary vasodilator with minimal effects on HR in mice, and that CFR increases with age and is reduced significantly in each disease model. Indeed, CFR is nearly abolished 3 wks after TAB. We conclude that the magnitudes of CFV and CFR and the responses to pressure overload hypertrophy and coronary artery disease are similar in mice and man and that global CFR may serve as an index of cardiac function.
Probing atelectasis using spherical indentation and optical coherence tomography
Authors: Silva Maricris Resurreccion , Kim Jae Hun , Gouldstone Andrew
Published: June 2021

Understanding of atelectasis is important for respiratory physiology, pathology, and clinical anesthesia. Studies of this occurrence are often limited to causal, because the specific mechanistic conditions are not controlled. In this investigation, we systematically induced atelectasis near the surface of excised lungs using load‐controlled indentation. Physiologic pressures were applied using spherical tips over spatial dimensions far larger than alveolar size to allow continuum discussions of stress‐induced collapse. After indentation, non‐invasive sub‐surface observation of the deformation was performed using optical coherence tomography (OCT). Experimental observations of atelectasis are compared with finite element model calculations of maximum stress loci. Tests were performed over a range of transpulmonary pressures, using air, 100% O2 and isoflurane mixtures. Significant differences were found in the atelectatic occurrence and recovery between inflation gases. These differences manifested within minutes, suggesting gas‐surfactant interaction. Accordingly, here we provide surfactant‐based arguments for our experimental observations.
Regulation of the intestinal mucin MUC2 expression by short chain fatty acids: implications for epithelial protection
Authors: Burger‐van Paassen Nanda , Vincent Audrey , Puiman Patrycja J , van der Sluis Maria , Bouma Janneke , Boehm Gunther , Van Goudoever Johannes B , Van Seuningen Isabelle , Renes Ingrid B
Published: June 2021

Short chain fatty acids (SCFAs) influence epithelial‐specific gene expression. We hypothesize that SCFAs affect mucin MUC2 expression and thereby epithelial protection. Aim: Study the effects of SCFAs on MUC2 expression.

Methods

LS174T cells were treated with SCFAs. MUC2 mRNA levels and stability and MUC2 protein expression were analyzed. SCFA‐responsive regions and cis‐elements within the MUC2 promoter were identified by transfection and gel shift assays. Effects on histone H3/H4 status at the MUC2 promoter were established by chromatin immunoprecipitation.

Results

Both 1 mM butyrate and propionate induced an increase in MUC2 mRNA levels. MUC2 mRNA levels returned to basal levels after incubation with 5‐15 mM of butyrate. This decrease was not due to loss of RNA stability. At 5‐15 mM of propionate MUC2 mRNA levels remained high. Promoter regulation studies revealed a butyrate‐responsive region in the MUC2 promoter containing an active AP1 cis‐element at ‐818/‐808 that mediates butyrate‐induced activation of the promoter. MUC2 regulation by butyrate at 10‐15 mM was associated with increased acetylation of histone H3/H4 and methylation of H3 at the promoter.

Conclusion

1 mM of butyrate and 1‐15 mM of propionate increase MUC2 expression. The effects of butyrate on MUC2 mRNA are mediated via AP‐1 and acetylation/methylation of histones. Thus SCFAs affect MUC2 expression and thereby intestinal protection.
Phenotypic variation in the etiology and pathogenesis of congenital craniofacial birth defects such as Treacher Collins syndrome
Authors: Trainor Paul
Published: June 2021

Neural crest cells gives rise to the majority of the bone, cartilage, connective and peripheral nerve tissues in the head and face. Craniofacial anomalies which account for approximately one third of all congenital birth defects arise largely through defects in neural crest cell patterning. Treacher Collins Syndrome (TCS) is a rare human congenital disorder of craniofacial development, characterised by developmental anomalies including hypoplasia of the facial bones, middle and external ear defects and cleft palate. TCS is associated with mutations in the TCOF1 gene which encodes a nucleolar protein known as treacle. More than 100 family specific mutations have been identified however there is no genotype‐phenotype correlation. We have characterised mouse models of Treacher Collins Syndrome via null mutation of Tcof1 which exhibit differing severity and penetrance on DBA and C57Bl/6 backgrounds. We are currently exploring spatiotemporal activity, endogenous levels and background specific modifiers as regulators of the etiology and pathogenesis of craniofacial malformations syndromes such as TCS.
From birth to adulthood in a nutshell : hematopoietic stem cell development in vitro & HOXB4
Authors: Klump Hannes , Lesinski Dietrich , Heinz Niels , Rainer Loew , Pilat Sandra , Carotta Sebastian , Beug Hartmut , Schiedlmeier Bernhard , Baum Christopher
Published: June 2021

Ectopic expression of the homeodomain transcription factor HOXB4 has been shown to enhance the in vivo repopulation ability of in vitro differentiated mouse ES‐cells. How it promotes the conversion of ES‐cells to HSCs is not yet known. Here we demonstrate that its expression enforces the development of the developmentally earliest known hematopoietic cell during ES‐cell differentiation and promotes its expansion in stroma‐cell free suspension cultures. As these cultures lead to long‐term engraftment after transplantation into Rag2(‐/‐)γ(‐/‐) mice, the ability to engraft may correlate with the presence of these earliest, CD41hi cells. To test whether the CD41+ subpopulation depends on expression levels of HOXB4, we designed new tetracycline regulatable cassettes in which all necessary components were embedded in a single retroviral vector.

The presence of a CD41hi / c‐Kit+/− / CD45− subpopulation correlated with HOXB4 expression levels in clonal ES‐HC cultures. This subpopulation was capable of reconstituting the entire heterogeneity of the primary suspension culture and differentiated towards all lineages in colony assays.

In summary, we show that HOXB4 expression enhances the in vitro generation and expansion of the earliest known HSCs from mouse ES‐cells. Its tight and fine‐tuned regulation may also support the generation and safe expansion of patient‐specific pluripotent stem cell derived HSCs.
Early heart morphogenesis: cellular and molecular perspectives
Authors: Linask Kersti K
Published: June 2021

Cardiomyocyte specification occurs during gastrulation and involves canonical Wnt signaling to define the heart fields. Acute exposure of the embryo during gastrulation to either the drug lithium (Li) or to homocysteine (HCy) in the folic acid cycle, gives rise to similar heart defects. Li mimics Wnt/beta‐catenin signaling by inactivating glycogen synthase kinase‐3. Li use during pregnancy is associated with Ebstein's Anomaly. We determined by echocardiography, that exposure of mouse embryos by an i.p. injection of Li/HCy on embryonic day E6.75 induces cardiac and valve defects. A single dose of Li (25 mM) or of HCy (75 µM) on E5.5‐6.5 results in mouse embryonic lethality; on E6.75‐7.0, both induce tricuspid and semilunar valve defects. The tricuspid valve septal leaflet fails to delaminate, a characteristic of Ebstein's Anomaly. During chick cardiac specification, Li, Wnt 3A, or HCy similarly affect chick cardiogenesis with severity of anomalies based on timing of exposure. The secreted Wnt antagonist Dickkopf‐1 acts extracellularly to repress Wnt signaling resulting in the upregulation of Hex, an inducer of cardiomyogenesis. Exposure of stages 3+/4 chick embryos to Li/Wnt3A/ HCys inhibits Hex and Islet‐1 gene expression in the cardiogenic crescent. Taken together, these results suggest Li and HCy effects on cardiac development intersect via an augmention of inhibitory Wnt/beta‐catenin signaling. Support: NHLBI; AHA
Regenerative medicine: learning to instruct our own cells
Authors: Gearhart John
Published: June 2021

Regenerative medicine, the restoration of tissues or cells lost to trauma, disease and wear, will encompass tissue and cell engineering, cell‐based interventions, material sciences, artificial and biohybrid organs, and biosurgery. Stem cells are serving not only as a source of cells for therapies (and potential therapies) but also as a source of basic science knowledge that will be utilized in regenerative medicine strategies. To develop safe and effective therapies we must be able to provide instructions to cells to behave and function in a tissue‐appropriate manner. These instructions can be provided by pre‐conditioning cells, the local tissue environment or through the reprogramming of cells to specific phenotypes. The new platform of directly reprogramming cells through the introduction of sets of genes, small molecules, etc., as illustrated by induced pluripotential cells, is ideally suited for user innovation in that it combines large numbers of users and a technology that has a modular or open design. These design characteristics create a common workbench for user innovators to generate reagents that will be appropriate for regenerative medicine, including direct use in the patient. Also, studies on regeneration, per se, will provide another important source of basic science knowledge that will impact on regenerative medicine.
6S RNA Regulation of Transcription
Authors: Wassarman Karen M , Klocko Andrew D , Cavanagh Amy
Published: June 2021

The 6S RNA forms a specific, stable complex with the σ70 containing form of RNA polymerase, resulting in down‐regulation of transcription at many promoters. We have shown that the 6S RNA is near the active site of RNA polymerase, and surprisingly can be used as a template for RNA synthesis analogous to transcription from a DNA promoter template. Studies of 6S RNA complexes revealed that 6S RNA remains stably bound to RNA polymerase when nutrients are limiting, but when nutrients become available, 6S RNA is released from RNA polymerase as a result of its use as a template for pRNA synthesis.

A phylogenetically conserved structure of 6S RNA is critical for function. This structure bears a striking resemblance to the DNA conformation in open complexes during transcription initiation, which suggested 6S RNA might contact RNA polymerase in a manner similar to DNA binding. Indeed, similar to DNA binding at most promoters, region 4.2 of σ70 is required for 6S RNA binding. However, analysis of the contribution of individual residues within region 4.2 of σ70 for 6S RNA binding revealed that RNA binding is distinct from promoter DNA binding. The nature of this 6S RNA‐RNA polymerase interaction as well as its impact on promoter specificity for 6S RNA regulation of transcription will be discussed.
Synergistic effect of green tea polyphenols and vitamin D on chronic inflammation‐induced bone loss in female rats
Authors: Shen Chwan‐Li , Yeh Jame K , Dunn Dale M , Cao Jay , Wang Jia‐Sheng
Published: June 2021

This study examines effects of green tea polyphenols (GTPs) in conjunction with vitamin D (vitD) on chronic‐inflammation‐induced bone loss in female rats. A 2 (no GTPs vs. GTPs) ×2 (no vitD vs. vitD) factorial design using 40 female rats assigned to 4 groups, lipopolysaccharide implantation (L), L+0.5% GTP (LG), L+vitD (LD), and LPS+0.5% GTP+vitD (LGD) for 12 wks. Supplementation of GTPs in the drinking water increased concentrations of epigallocatechin in urine of rats. GTPs supplementation resulted in a decrease in inflammation index (total white blood cell count, WBC), DNA oxidative damage biomarker (8‐hydroxydeoxyguanosine level, 8‐OHdG), and bone resorption biomarker (tartrate resistant acid phosphatase, TRAP), no change in bone formation biomarker (osteocalcin, OC), and an increase in bone mineral density (BMD). VitD treatment also led to a reduction of 8‐OHdG and TRAP, no change in OC, and an increase in BMD. A combination of GTPs and vitD treatments resulted in a synergistic effect on BMD. These results demonstrated that GTPs in conjunction with vitD treatment mitigates LPS‐induced bone loss in female rats. Such a synergistic role of GTPs and vitD may be, in part, attributed to decreased inflammation and oxidative stress. This study suggests a potentially significant prophylactic role of green tea and vitD in bone health of women with chronic inflammation‐induced bone loss.
Soy genistein prevents streptozotocin‐induced diabetes through regulation of pancreatic beta‐cell function
Authors: Liu Dongmin , Fu Zhuo
Published: June 2021

Loss of β‐cell mass and function are central to the development of diabetes. In the present study, we found that soy genistein induced clonal and human pancreatic β‐cell proliferation, with 5 µM genistein inducing a maximal 41% increase. The effect of genistein on cell proliferation was neither dependent on estrogen receptors, nor shared by a host of structurally related compounds. Pharmacological or molecular intervention of PKA or ERK1/2 completely abolished the genistein‐stimulated proliferation of INS1 cells and human islets, suggesting that both molecules are essential for genistein action. Consistently, genistein activated cAMP/PKA and ERK1/2 signaling in β‐cells. Furthermore, we found that genistein induced protein expression of cyclin D1, a major cell‐cycle regulator essential for β‐cell growth. We also show that genistein promoted viability, reduced caspase‐3 activity and induced anti‐apoptotic protein Bcl‐2 expression in islet cells. Dietary genistein intake increased plasma levels of insulin and ameliorated hyperglycemia in Streptozotocin (STZ) induced diabetic mice. These effects were associated with improved islet mass and protected islets from STZ‐induced apoptosis in these mice. These findings demonstrate that genistein may be a novel regulator of pancreatic β‐cell function via activation of multiple intracellular signaling pathways, thereby providing an anti‐diabetic effect.
Age‐related changes in tissue copper (Cu) and iron (Fe) levels in the Ctr‐1 mouse
Authors: Scherr Rachel Erin , Chew Michael , Le Anh , Keen Carl L. , Uriu‐Adams Janet Y.
Published: June 2021

Ctr‐1, a membrane bound protein, is the primary transporter for Cu into the cell. While Ctr‐1 null mice die early in gestation, heterozygous Ctr‐1 mice are phenotypically normal. We characterized tissue Cu and Fe levels in Ctr‐1 and wildtype (WT) mice at 4 developmentally important timepoints (2, 6, 12 and 18 months). Data show an age‐related decrease in liver Cu levels which was larger in Ctr‐1 mice compared to WT. Similarly, plasma Cu was lower in Ctr‐1 mice compared to WT. Despite these differences, hepatic CuZnSOD and plasma ceruloplasmin activities were similar. Cu concentrations in Ctr‐1 brain regions (medulla pons, cerebrum, cerebellum) were 50% lower than WT at all timepoints. Even with these marked differences, preliminary data showed no evidence of brain nitrosative damage (3‐nitrotyrosine) or altered neurobehavior (rotorod performance) in the Ctr‐1 mice, outcomes which would be expected with dietary Cu deficiency. We suggest that this might be due to a lack of an effect of the Ctr‐1 heterozygosity on Fe metabolism since brain Fe levels are typically low with dietary Cu deficiency, but were unaffected in the Ctr‐1 mice. We propose that the Ctr‐1 model provides a novel approach to studying the specific effects of a deficit of Cu on brain development, relative to the combined effects of deficits of both Cu and Fe that occur with dietary Cu deficiency. (Supported by CHNR 08‐804).
Temporal and functional study of TGFβ regulated genes during chicken AV canal formation
Authors: Tavares Andre Luiz Pasqua , Runyan Raymond Bruce
Published: June 2021

In the atrioventricular canal (AVC) of the embryonic heart, endothelia undergo an epithelial‐mesenchymal transition (EMT). This EMT is a multi‐step event, wherein TGFß2 mediates activation while TGFß3 mediates cell invasion. BMP2 has an unclear role in this EMT. We examined in vivo and in vitro patterns of expression of EMT‐related genes. In the chick, EMT is seen at stage 17 although signaling processes begin at stage 14. Our objective is to identify critical transcription factor function during EMT. We examined mRNA for Sox8, Sox11, Sip1, Brachyury, Hey2 and Runx2 by qPCR. Starting at stage 14, Sox8 and Hey2 showed upregulation while Brachyury was downregulated. Sip1 and Runx2 were down‐regulated only after EMT was visible. Sox11 mRNA levels did not show significant change (stages 14‐20). We explored changes in expression after TGFβ2, TGFβ3 or BMP inhibition of AVC explants on collagen gels. Anti‐TGFβ2 treatment produced significant upregulation of Sox8 and down‐regulation of Sox11, Sip1 and Runx2 while anti‐TGFβ3 treatment caused significant down‐regulation of Sox8, Sip1 and Runx2. Noggin treatment caused significant upregulation of Sox8, Sox11, Sip1 and Hey2 and down‐regulation of Brachyury. Localization of these molecules showed they were present in AVC endothelium and mesenchyme at the analyzed stages. These data suggest that each of these transcription factors may play a role in cardiac EMT. NHLBI.

Grant Funding Source

NHLBI
Mean daily intake of calcium, folate and vitamin D from dietary supplements and the proportion getting above certain Dietary Reference Intake (DRI) levels, in the U.S. population ages 14 years and older: Third National Health and Nutrition Examination Survey (NHANES III) and NHANES, 1999‐2006
Authors: Wilger ‐ Gahche Jaime Jacqueline , Bailey Regan Lucas , Burt Vicki L , Radimer Kathy , McDowell Margaret , Picciano Mary Frances , Dwyer Johanna , Sempos Chris
Published: June 2021

Mean daily intakes were estimated for calcium, folate and vitamin D from dietary supplements (DS) for the non‐pregnant/non‐lactating U.S. population ages 14 years and older from NHANES III (n=18493) and NHANES 1999‐2006 (n=24396). NHANES is a nationally representative cross‐sectional survey of the U.S. population. DS use is collected through an in‐person interview to ascertain the type and name of DS, frequency, dosage, amount consumed and duration of use. 39.7% (NHANES III) and 49.8% (1999‐2006) reported taking DS in the past 30 days. DS users 14 years and older took DS containing the following: calcium, 49.0% (NHANES III) and 79.9% (1999‐2006); mean intake was 278mg (NHANES III) and 344mg (1999‐2006); folic acid, 69.8% (NHANES III) and 72.5% (1999‐2006); mean intake was 419mcg (NHANES III) and 385mg (1999‐2006); and vitamin D, 65.2% (NHANES III) and 72.3% (1999‐2006); mean intake was 10mcg (NHANES III) and 9mcg (1999‐2006). Many individuals met DRI recommendations through DS alone. For example, 63.5% (1999‐2006) met the Recommended Daily Allowance for folate and in certain groups intakes from DS exceeded the Upper Limit. There has been a marked increase in DS use in the past 20 years in the U.S. DS can contribute up to 100% of the daily values, and are contributing to adequacy of nutrient intake. Furthermore, there may be a possible risk of nutrient toxicity, especially when taking into account nutrient intake from foods.
Milk consumption and cholesterol homeostasis in postmenopausal women with abdominal obesity
Authors: Lamarche Benoit , Labonté Marie‐Eve , Gagnon Josée , Desroches Sophie , Charest Amélie , Lemieux Simone , Couture Patrick
Published: June 2021

The objective of this study was to investigate using a randomized, cross over study design the impact of milk consumption on markers of cholesterol absorption and synthesis in postmenopausal women with abdominal obesity. Twenty‐seven women with abdominal obesity consumed under controlled conditions a diet rich in milk (MILK) and a control diet designed according to the National Cholesterol Education Program (NCEP) dietary recommendations, in a random order for 6 weeks each. The macronutritional composition of both diets was comparable (55% carbohydrates, 15% proteins, 30% fat and 10% saturated fat). Milk accounted for 20% of energy intake in the MILK diet. Neither the MILK nor the NCEP diet had an impact on plasma cholesterol, triacylglycerol and apolipoprotein (apo) B concentrations. However, the plasma concentration of β‐sitosterol, a surrogate of intestinal cholesterol absorption, was reduced after the MILK diet compared with NCEP control diet (‐9.2%, P=0.07). The β‐sitosterol/lathosterol ratio, a marker of cholesterol homeostasis that shows a strong correlation with abdominal obesity, was also reduced significantly after the MILK diet compared with the NCEP diet (‐14.9%, P=0.01). These data suggest that while milk consumption may have little effect on plasma cholesterol concentration, it may be associated with subtle but significant changes in cholesterol homeostasis in women with abdominal obesity.
Glycemic response related more strongly to glycemic index (GI) of diet than to carbohydrate (CHO) level
Authors: Most Marlene M , Cefalu Will , Greenway Frank , McGlone Meghan , Jonnalagadda Satya
Published: June 2021

Diets with low GI or low glycemic load (GL) are independently associated with reduced risk of chronic disease. Although low GI foods that produce small fluctuations in blood glucose and insulin may be advantageous for health, factors such as the amount of CHO consumed must be considered. Additionally, low GI foods may increase satiety influencing body weight regulation, yet their effect may be limited by the CHO level. We examined 4 diets differing in GL on glycemic response, hunger and satiety in healthy adults. Mixed meals (breakfast, lunch, dinner) were constructed by manipulating GI (high = 85; low = 67) and carbohydrate (high = 56%en; low = 40%en). Protein and fiber were constant. Ten men and 16 women (BMI=29) consumed the diets in a randomized crossover design following a 3‐day standard diet. Blood samples were collected at fasting and at defined intervals for 12 hours. The high CHO, high GI meals created the greatest glucose response. However, with the high CHO diet, low GI mitigated the glycemic response. Low GI regardless of CHO level becomes essential following lunch and dinner. Hunger and satiety VAS ratings were similar among the 4 diets. Both GI and CHO level work together to improve glucose and insulin excursions. Supported by The General Mills Bell Institute of Health and Nutrition, Minneapolis MN.
Aging of Cardiac Stem Cells
Authors: Kajstura Jan
Published: June 2021

Heart failure is the leading cause of death in the elderly but whether this is the result of a primary aging myopathy dictated by depletion of the cardiac progenitor cell (CPC) pool is unknown. Similarly, whether current lifespan reflects the ineluctable genetic clock or heart failure interferes with the genetically‐determined fate of the organ and organism is an important unanswered question. By measuring the number and function of CPCs in the aging heart, we have identified that chronological age leads to telomeric shortening in CPCs which by necessity generate differentiated progeny that rapidly acquire the senescent phenotype. CPC aging is conditioned by attenuation of the IGF‐1‐IGF‐1R and HGF‐c‐Met systems which do not counteract any longer the CPC renin‐angiotensin‐system, resulting in cellular senescence, irreversible growth arrest and apoptosis. However, a subset of telomerase‐competent CPCs with long telomeres is present in the senescent heart and following activation these CPCs migrate to the regions of damage where they generate a population of young cardiomyocytes reversing in part the aging myopathy. The senescent heart phenotype and heart failure are partially corrected leading to prolongation of maximum lifespan.
Aging and Vascular Progenitor Cells
Authors: DeSouza Christopher
Published: June 2021

Endothelial injury without a sufficient compensatory reparative response is thought to accelerate the progression of cardiovascular disease and its clinical consequences including death. Circulating vascular progenitor cells, particularly endothelial progenitor cells (EPCs), are recognized to play a critically important role in maintaining, repairing and/or regenerating the endothelial monolayer and restoring functional activity. The continuous circulation of EPCs is considered to be an important haemostatic mechanism of counteracting ongoing vascular injury in order to preserve organ viability. In addition to reendothelilaization, EPCs also contribute significantly to post natal neovascularization. EPC dysregulation has been linked to a number of pathologies associated with increased cardiovascular risk, including aging. This platform session will outline the adverse influence of advancing age on EPC functional characteristics and their association with age‐related endothelial dysfunction.