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In situ bioprinting—the process of depositing bioinks at a defected area, has recently emerged as a versatile technology for tissue repair and restoration via site-specific delivery of pro-healing constructs. The ability to print multiple materials in situ is an exciting approach that allows simultaneous or sequential dispensing of different materials and cells to achieve tissue biomimicry. Herein, we report a modular handheld bioprinter that deposits a variety of bioinks in situ with exquisite control over their physical and chemical properties. Combined stereolithography 3D printing and microfluidic technologies allowed us to develop a novel low-priced handheld bioprinter. The ergonomic design of the handheld bioprinter facilitate the shape-controlled biofabrication of multi-component fibers with different cross-sectional shapes and material compositions. Furthermore, the capabilities of the produced fibers in the local delivery of therapeutic agents was demonstrated by incorporating drug-loaded microcarriers, extending the application of the printed fibers to on-demand, temporal, and dosage-control drug delivery platforms. Also, the versatility of this platform to produce biosensors and wearable electronics was demonstrated via incorporating conductive materials and integrating pH-responsive dyes. The handheld printer’s efficacy in generating cell-laden fibers with high cell viability for site-specific cell delivery was shown by producing single-component and multi-component cell-laden fibers. In particular, the multi-component fibers were able to model the invasion of cancer cells into the adjacent tissue.

Background: Individuals born preterm present left ventricle changes and increased risk of cardiac diseases and heart failure. The pathophysiology of heart disease after preterm birth is incompletely understood. Mitochondria dysfunction is a hallmark of cardiomyopathy resulting in heart failure. We hypothesized that neonatal hyperoxia in rats, a recognized model simulating preterm birth conditions and resulting in oxygen-induced cardiomyopathy, induce left ventricle mitochondrial changes in juvenile rats. We also hypothesized that humanin, a mitochondrial-derived peptide, would be reduced in young adults born preterm. Methods: Sprague-Dawley pups were exposed to room air (controls) or 80% O 2 at postnatal days 3 to 10 (oxygen-induced cardiomyopathy). We studied left ventricle mitochondrial changes in 4 weeks old males. In a cohort of young adults born preterm (n=55) and age-matched term (n=54), we compared circulating levels of humanin. Results: Compared with controls, oxygen-exposed rats showed smaller left ventricle mitochondria with disrupted integrity on electron microscopy, decreased oxidative phosphorylation, increased glycolysis markers, and reduced mitochondrial biogenesis and abundance. In oxygen-exposed rats, we observed lipid deposits, increased superoxide production (isolated cardiomyocytes), and reduced Nrf2 gene expression. In the cohort, left ventricle ejection fraction and peak global longitudinal strain were similar between groups however humanin levels were lower in preterm and associated with left ventricle ejection fraction and peak global longitudinal strain. Conclusions: In conclusion, neonatal hyperoxia impaired left ventricle mitochondrial structure and function in juvenile animals. Serum humanin level was reduced in preterm adults. This study suggests that preterm birth–related conditions entail left ventricle mitochondrial alterations that may underlie cardiac changes perpetuated into adulthood. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03261609.

Individuals born preterm show reduced exercise capacity and increased risk for pulmonary and cardiovascular diseases, but the impact of preterm birth on skeletal muscle, an inherently critical part of cardiorespiratory fitness, remains unknown. We evaluated the impacts of preterm birth-related conditions on the development, growth, and function of skeletal muscle using a recognized preclinical rodent model in which newborn rats are exposed to 80% oxygen from day 3 to 10 of life. We analyzed different hindlimb muscles of male and female rats at 10 days (neonatal), 4 weeks (juvenile) and 16 weeks (young adults). Neonatal high oxygen exposure increased the generation of reactive oxygen species and the signs of inflammation in skeletal muscles, which was associated with muscle fiber atrophy, fiber type shifting (reduced proportion of type I slow fibers and increased proportion of type IIb fast-fatigable fibers), and impairment in muscle function. These effects were maintained until adulthood. Fast-twitch muscles were more vulnerable to the effects of hyperoxia than slow-twitch muscles. Male rats, which expressed lower antioxidant defenses, were more susceptible than females to oxygen-induced myopathy. Overall, preterm birth-related conditions have long-lasting effects on the composition, morphology, and function of skeletal muscles; and these effects are sex-specific. Oxygen-induced changes in skeletal muscles could contribute to the reduced exercise capacity and to increased risk of diseases of preterm born individuals.

Background Increasing thoracic expansion is effective at reducing blood pressure in hypertensive subjects. Yoga prescribes many respiratory techniques with a growing number of practitioners. However, very little is known whether sedentary or yoga practitioners show measurable differences in their respiratory patterns. Objective This study aims to demonstrate differences between healthy sedentary individuals and healthy yoga practitioners regarding maximal respiratory pressures and thoracic and abdominal respiratory expansibility. Methods Maximal inspiratory and expiratory pressures (MIP and MEP, respectively) were evaluated by [...]

BACKGROUND Anemia of prematurity is common in extremely preterm neonates, and oxygen exposure may participate to anemia by inhibiting erythropoietin secretion. We aimed to determine whether hyperoxia exerts an independent role in the occurrence of the anemia of prematurity. METHODS Sprague-Dawley pups were exposed to 80% oxygen or room air from days 3 to 10 of life. Main outcome was the difference in hemoglobin and circulating erythropoietin levels in animals exposed to hyperoxia at 10 days of life. We performed a complete blood count analysis using fluorescent laser flow cytometry and measured circulating erythropoietin levels using ELISA. RESULTS We found lower hemoglobin in the hyperoxia group, compared to the normoxia group, both in males (70 ± 3 versus 78 ± 2 g/l) and in females (71 ± 2 versus 81 ± 3 g/l) at 10 days of life. Reticulocyte count was not increased in the hyperoxia group. Circulating erythropoietin levels were lower at 10 days of life in the animals exposed to hyperoxia, both in males (33 ± 7 versus 73 ± 6 pg/ml) and in females (37 ± 5 versus 66 ± 3 pg/ml), but were similar at 28 days of life. CONCLUSION Neonatal exposure to hyperoxia decreases hematopoiesis in rats. IMPACT Mechanisms leading to anemia of prematurity are not well known and their study in humans is complicated due to multiple confounders. This study shows for the first time that exposure to high concentrations of oxygen in the neonatal period decreases hematopoiesis in rats, providing insight on the pathophysiological mechanisms of the anemia of prematurity. This research paves the way for future therapeutic developments aiming to reduce the burden of anemia of prematurity and the necessity of red blood cell transfusions in extremely preterm neonates.

Introduction: Preterm (PT) birth is associated with increased risk of cardiovascular diseases (CVD) and heart failure. We previously reported left ventricular (LV) mitochondrial dysfunction in a rat model mimicking the deleterious conditions associated with PT birth. Whether mitochondrial function is altered in humans born PT and associated with LV function changes is unknown. We aimed to determine if serum humanin levels, a mitochondrial-derived peptide with cytoprotective effects, are altered in humans born PT and are associated with impaired myocardial function. Methods: Data were obtained from 55 young adults born PT ( Results: Individuals were evaluated at 23.3 (21.4, 25.3) years, and age and sex distribution were similar between groups. Median GA was 27.5 (26.2, 28.4) weeks in the PT group. Humanin levels (pg/ml) were 132.9 (105.1, 189.3) and 161.1 (123.6, 252) in the PT and the T groups, respectively (p=0.0414). LVEF was within the normal range and similar between groups. Lower LVEF was associated with lower humanin levels (p Conclusions: Serum humanin levels are lower in adult born PT. Since lower humanin levels are also associated with lower LVEF, our results suggest that mitochondrial alterations could play a role in the long-term adverse cardiovascular consequences of PT birth. Humanin analogs improve LV function in experimental models. Our results pave the way for future studies exploring humanin as a therapeutic avenue for the prevention and treatment of CVD in individuals born PT.

Adults born preterm are at a higher risk of cardiopulmonary disease and premature death. Preterm birth is associated with abnormalities in right ventricular (RV) structure and function, but the impact of bronchopulmonary dysplasia (BPD), a common complication of extremely preterm birth, on these parameters remains unknown.Are preterm birth and BPD associated with alterations in RV structure and function in early adulthood?Echocardiographic and spirometry data were obtained from the Health of Adults Born Preterm Investigation (HAPI). RV structure and performance were evaluated by using echocardiography, and respiratory function was assessed by using spirometry.The study comprised 86 young adults born preterm before 30 weeks of gestation, including 28 with moderate to severe BPD, and 85 adults of the same age born full term. Individuals were assessed at a mean age of 23 years. RV systolic function was altered in the preterm group, with lower tricuspid annular plane systolic excursion and lower RV s' and RV outflow tract velocity time integral values, especially in those born preterm with BPD. Nine (36%) participants born preterm with BPD, six (13%) participants born preterm without BPD, and six (8%) participants born full term had a tricuspid annular plane systolic excursion value 16 mm, a marker of RV systolic dysfunction (P value for the comparison between preterm no BPD and BPD, .032). No difference was found in RV diastolic function or estimates of pulmonary artery pressure between groups. Although respiratory function was altered in those born preterm, and more so in the case of BPD, no association was observed between spirometry indices of respiratory function and RV systolic function.Preterm birth is associated in adulthood with alterations in RV systolic function, which are more pronounced in the case of BPD.ClinicalTrials.gov; No.: NCT03261609; URL: www.clinicaltrials.gov.

Preterm birth incurs an increased risk of early cardiovascular events and death. In the general population, cardiovascular risk factors cluster in the context of inflammation and oxidative stress. Whether this also occurs in young adults born preterm is unknown. We analyzed 101 healthy young adults (ages 18–29) born preterm (≤29 weeks of gestation) and 105 full-term controls, predominantly (90%) white. They underwent a comprehensive clinical and biological evaluation, including measurement of blood pressure, lung function (spirometry), glucose metabolism (fasting glucose, glycated hemoglobin, and oral glucose tolerance test), as well as biomarkers of inflammation and oxidative stress. Individuals born preterm were at higher risk than those born full-term of stage ≥1 hypertension (adjusted odds ratio, 2.91 [95% CI, 1.51–5.75]), glucose intolerance (adjusted odds ratio, 2.22 [95% CI, 1.13–4.48]), and airflow limitation (adjusted odds ratio, 3.47 [95% CI, 1.76–7.12]). Hypertension was strongly associated with adiposity and with glucose intolerance in participants born full-term but not in those born preterm. We did not find any group difference in levels of biomarkers of inflammation and oxidative stress. In individuals born preterm, inflammation, and oxidative stress were not related to hypertension or glucose intolerance but were associated with adiposity. In those born preterm, cardiovascular risk factors were not related to each other suggesting different pathophysiological pathways leading to the development of cardiovascular risk following preterm birth. Clinicians should consider screening for these abnormalities irrespectively of other risk factors in this at-risk population. Clinical Trial Registration URL: http://www.clinicaltrials.gov . Unique identifier: NCT03261609.

Angiotensin-(1-7) counterbalances angiotensin II cardiovascular effects. However, it has yet to be determined how cardiovascular autonomic modulation may be affected by chronic and acute elevation of Ang-(1-7). Hemodynamics and cardiovascular autonomic profile were evaluated in male Sprague-Dawley (SD) rats and transgenic rats (TGR) overexpressing Ang-(1-7) [TGR(A1-7)3292]. Blood pressure (BP) was directly measured while cardiovascular autonomic modulation was evaluated by spectral analysis. TGR received A-779 or vehicle and SD rats received Ang-(1-7) or vehicle and were monitored for 5 h after i.v. administration. In another set of experiments with TGR, A-779 was infused for 7 days using osmotic mini pumps. Although at baseline no differences were observed, acute administration of A-779 in TGR produced a marked long-lasting increase in BP accompanied by increased BP variability (BPV) and sympathetic modulation to the vessels. Likewise, chronic administration of A-779 with osmotic mini pumps in TGR increased heart rate, sympathovagal balance, BPV, and sympathetic modulation to the vessels. Administration of Ang-(1-7) to SD rats increased heart rate variability values in 88% accompanied by 8% of vagal modulation increase and 18% of mean BP reduction. These results show that both acute and chronic alteration in the Ang-(1-7)-Mas receptor axis may lead to important changes in the autonomic control of circulation, impacting either sympathetic and (or) parasympathetic systems.

It has been shown that angiotensin(1–7) (Ang(1–7)) produces several effects related to glucose homeostasis. In this study, we aimed to investigate the effects of genetic deletion of Ang(1–7), the GPCR Mas, on the glucagon-producing cells. C57BL6/N Mas−/− mice presented a significant and marked increase in pancreatic α-cells (number of cells: 146 ± 21 vs 67 ± 8 in WT; P P P P −/− mice (0.25 ± 0.01 vs 0.31 ± 56.45 pg/mL in WT; P = 0.02). In order to eliminate the possibility of a background-related phenotype, we determined the number of glucagon-producing cells in FVB/N Mas−/− mice. In keeping with the observations in C57BL6/N Mas−/− mice, the number and percentage of pancreatic α-cells were also significantly increased in these mice (number of α-cells: 260 ± 22 vs 156 ± 12 in WT, P P

We previously reported that neonatal blockade of angiotensin II AT

Inspiratory muscle exercise (IME) can be an alternative to conventional exercise. We aimed to evaluate the effect of IME on glucose, glucose variability, and autonomic cardiovascular control in type 2 diabetes. Fourteen diabetic subjects were randomly assigned to IME with 2% maximal inspiratory pressure (PImax) or 60% PImax wearing a continuous glucose monitoring system for three days. Glucose variability [glucose variance (VAR), glucose coefficient of variation (CV%), glucose standard deviation (SD), and mean amplitude of glycemic excursions (MAGE)] were evaluated. Glucose reduction was observed in 5 min (60% of PImax 33.2% and 2% of PImax 32.0%), 60 min (60% of PImax 29.6% and 2% of PImax 31.4%) and 120 min (60% of PImax 21.4% and 2% of PImax 24.0%) after IME (vs.1 h before the exercise), with no difference between loads. This reduction in glucose levels was observed in all moments of the IME protocol. Glucose variability was reduced after 12 h and 18 h of the IME (ΔCV: P 0.001, ΔSD: P 0.001 and ΔVAR: P 0.001) for both loads. No difference was found in MAGE (P = 0.594) after IME. Mean arterial pressure and heart rate rose during the exercise session with 60% of PImax. Although sufficiently strong to induce cardiovascular changes, an inspiratory muscle exercise session with 60% of PImax in subjects with type 2 diabetes has failed to induce any significant improvement in glucose, glucose variability and autonomic control, compared to the 2% Plmax exercise session.

The heart relies on adequate mitochondrial (mito) ATP production to match myocardial demand, mostly through oxidative phosphorylation. Preterm birth (PT) results in ex utero development of an immature myocardium and PT-born individuals represent a newly recognized group at high risk of cardiovascular diseases. Our group has shown that newborn rats exposed to high oxygen (O 2 ), mimicking PT-related conditions, develop O 2 -induced cardiomyopathy (OIC) and dysfunction later in life. However, whether mito impairments prevail in the programmed left ventricle (LV) changes associated with PT is unknown. We aimed to determine whether OIC is associated with altered LV mito characteristics in 4 wks-old rats. Male rat pups were kept with their mother in 80% O 2 (OIC) or room air (Ctrl) from days 3 to 10 of life. Results are mean±SEM; OIC vs. Ctrl are compared using t-test (n=4/group.P2 consumption rate in OIC (12.14±5.74 vs. 67.39±13.61 pmoles/min/ug). OIC rats show reduced LV mito copy number determined by the ratio between mito and genomic DNA (26.7±6.30 vs. 52.7±7.32), biogenesis markers Pgc1α (0.59±0.14 vs. 1.18±0.25), and citrate synthase (0.20±0.16 vs. 1.60±0.56) mRNA, and reduced Complex IV (0.66±0.15 vs. 1.26±0.09) protein expression. Gene expression (RT-PCR) of key glycolytic enzymes, hexokinase (3.34±0.59 vs. 0.88±0.39) and glucose-6-phosphate dehydrogenase (2.85±0.48 vs. 0.58±0.08) is significantly increased, indicating a shift toward glycolysis. OIC also were found to have higher LV mtROS production (7581±51 vs. 5191±99, fluorescence arbitrary units) and decreased antioxidant SOD2 protein expression (0.84±0.09 vs. 1.04±0.05). Taken together our results indicate that neonatal hyperoxia exposure leads to decreased LV mito biogenesis and function with impaired oxidative phosphorylation capacity in juvenile animals. Further studies are needed to determine the role of long-term mito dysfunction in the increased susceptibility to heart failure observed after deleterious neonatal conditions.

AIM To examine the interference of β-blockers with the chemokine stromal cell-derived factor-1 (SDF-1) found in cell homing receptors, C-X-C chemokine receptor type 4 (CXCR-4) and CXCR-7, and regulatory proteins of homing pathways, we administered atenolol, carvedilol, metoprolol, and propranolol for 30 days using an orogastric tube to hypertensive rats. METHOD We collected blood samples before and after treatment and quantified the levels of SDF-1 with enzyme-linked immunosorbent assay (ELISA). On day 30 of treatment, the spontaneously hypertensive rats (SHR) were euthanized, and heart, liver, lung, and kidney tissues were biopsied. Proteins were isolated for determining the expression of CXCR-4, CXCR-7, GRK-2 (G protein-coupled receptors kinase 2), β-arrestins (β1-AR and β2-AR), and nuclear factor kappa B (NFκB). RESULTS We found that the study drugs modulated these proteins, and metoprolol and propranolol strongly affected the expression of β1-AR (P = .0102) and β2-AR (P = .0034). CONCLUSION β-blockers modulated tissue expression of the proteins and their interactions following 30 days of treatment. It evidences that this class of drugs can interfere with proteins of cell homing pathways.

Stress has been shown to negatively affect the immune system, alter the body's metabolism, and play a strong role in the development of mood disorders. These effects are mainly driven through the release of hormones from the hypothalamic–pituitary–adrenal axis (HPA). Additionally, women are more likely to be affected by stress due to the estrogen fluctuation associated with their menstrual cycle. This study aims to evaluate the effect of chronic restraint stress, applied for 30 days, and estrogen replacement on behavior, glucose level, and the lipid profile of ovariectomized rats. Our results suggest that stress increases sweet food consumption in OVX females treated with estradiol (E2), but reduces consumption in animals not treated. Furthermore, stress increases locomotor activity and anxiety as assessed by the Open Field test and in the Elevated Plus Maze. Similarly, our results suggest that E2 increases anxiety in female rats under the same behavioral tests. In addition, stress reduces glucose and TC levels. Moreover, stress increase TG levels in the presence of E2 and decrease in its absence, as well as the estradiol increase TG levels in stressed groups and reduced in non-stressed groups. Our data suggest an important interaction between stress and estrogen, showing that hormonal status can induce changes in the animal's response to stress.

Low angiotensin-(1-7) (Ang-(1-7)) concentration is observed in some cardiovascular diseases and exercise training seems to restore its concentration in the heart. Recently, a novel formulation of an orally active Ang-(1-7) included in hydroxy-propyl-beta-cyclodextrin (HPB-CD) was developed and chronically administered in experimental models of cardiovascular diseases. The present study examined whether chronic administration of HPB-CD/Ang-(1-7) produces beneficial cardiovascular effects in spontaneously hypertensive rats (SHR), as well as to compare the results obtained with those produced by exercise training. Male SHR (15-week old) were divided in control (tap water) or treated with HPB-CD/Ang-(1-7) (corresponding to 30μgkg(-1)day(-1) of Ang-(1-7)) by gavage, concomitantly or not to exercise training (treadmill, 10 weeks). After chronic treatment, hemodynamic, morphometric and molecular analysis in the heart were performed. Chronic HPB-CD/Ang-(1-7) decreased arterial blood pressure (BP) and heart rate in SHR. The inclusion compound significantly improved left ventricular (LV) end-diastolic pressure, restored the maximum and minimum derivatives (dP/dT) and decreased cardiac hypertrophy index in SHR. Chronic treatment improved autonomic control by attenuating sympathetic modulation on heart and vessels and the SAP variability, as well as increasing parasympathetic modulation and HR variability. Overall results were similar to those obtained with exercise training. These results show that chronic treatment with the HPB-CD/Ang-(1-7) inclusion compound produced beneficial effects in SHR resembling the ones produced by exercise training. This observation reinforces the potential cardiovascular therapeutic effect of this novel peptide formulation.

We previously reported that neonatal blockade of angiotensin II AT1 receptor prevents cardiac changes in 4 weeks rats with neonatal hyperoxia-induced cardiomyopathy, a recognized model of prematurity-related deleterious conditions. Considering the importance of AT1 receptor and the renin angiotensin system (RAS) in normal development, the present study aimed to investigate the adult effects of neonatal AT1 blockade on left ventricle (LV) in rats exposed to neonatal hyperoxia. Sprague-Dawley pups were exposed to 80% O2 or room air from days 3-10. AT1 blocker (losartan) or H2O were given by gavage from day 8-10. LV function (echo and intraventricular pressure), histology and expression of RAS components were examined in 15-16 weeks old adult males. Losartan treatment prevented myocardial fibrosis, LV wall thickening and stroke volume reduction in rats exposed to high O2 in the neonatal period. However, Losartan treatment of O2-exposed pups led to reduced ejection fraction (EF) and fractional shortening (FS), and did not prevent changes in diastolic function. Losartan also did not prevent increased LV AT2 and decreased angiotensin-(1-7) Mas receptors expression observed in high O2-exposed rats. Neonatal Losartan attenuated long-term impact of neonatal hyperoxia but also led to decreased EF and FS. Increased AT2 and decreased Mas receptor expression observed in O2-exposed group were unaffected by Losartan treatment. Our results show that early life Losartan treatment aimed at preventing cardiac consequences of neonatal deleterious conditions may also comprise detrimental effects that require further investigation prior to clinical translation in developing children.

Introduction: The angiotensin-converting enzyme 2 (ACE2)/angiotensin (Ang)-(1–7)/Mas axis could modulate the heart rate (HR) and blood pressure variabilities (BPV) which are important predictors of cardiovascular risk and provide information about the autonomic modulation of the cardiovascular system. Therefore we investigated the effect of Mas deficiency on autonomic modulation in wild type and Mas-knockout (KO) mice. Methods: Blood pressure was recorded at high sample rate (4000 Hz). Stationary sequences of 200–250 beats were randomly chosen. Frequency domain analysis of HR and BPV was performed with an autoregressive algorithm on the pulse interval sequences and on respective systolic sequences. Results: The KO group presented an increase of systolic arterial pressure (SAP; 127.26±11.20 vs 135.07±6.98 mmHg), BPV (3.54±1.54 vs 5.87±2.12 mmHg2), and low-frequency component of systolic BPV (0.12±0.11 vs 0.47±0.34 mmHg2). Conclusions: The deletion of Mas receptor is associated with an increase of SAP and with an increased BPV, indicating alterations in autonomic control. Increase of sympathetic vascular modulation in absence of Mas evidences the important role of Ang-(1–7)/Mas on cardiovascular regulation. Moreover, the absence of significant changes in HR and HRV can indicate an adaptation of autonomic cardiac balance. Our results suggest that the Ang-(1–7)/Mas axis seems more important in autonomic modulation of arterial pressure than HR.

Hypertensive patients have a higher risk of developing health complications, particularly cardiovascular (CV) events, than individuals with normal blood pressure (BP). Severity of complications depends on the magnitude of BP elevation and other CV risk factors associated with the target organ damage. Therefore, BP control and management of organ damage may contribute to reduce this risk. BP variability (BPV) has been considered a physiological marker of autonomic nervous system control and may be implicated in increased CV risk in hypertension. This review will present some evidence relating BPV and target organ damage in hypertension in clinical and experimental settings.