In this study, an experimental and numerical characterization of the viscohyperelastic behavior of suspended epithelial ARPE-19 cells is carried out using the micropipette aspiration technique, with particular emphasis on the evaluation of two viscoelastic models with different mathematical formulations, which were implemented in an in-house finite element code. The tests, conducted under one and two-ramp aspiration protocols, revealed variations in the measured mechanical properties of the cells, which are first sensitive to the applied pressure levels; This dependency is attributed to the internal organization of subcellular components. Second, the aspiration tests show that the apparent elastic modulus is dependent to the applied pressure rate. Two visco-hyperelastic models were evaluated to replicate the experimentally observed behavior. Although both models successfully fit the results, the LM model proved to be more efficient, requiring fewer parameters and enabling a clearer physical interpretation of the viscoelastic properties. In the numerical calculations, a time- and geometry-dependent load function was implemented, which optimally replicated the experimental observations while maintaining low computational cost.

Fetal growth restriction (FGR) is a pregnancy complication associated with increased perinatal morbidity and mortality in the short term, along with an elevated risk of developing cardiometabolic diseases in the long term. FGR is also associated with vascular dysfunction in the fetoplacental unit. In this work, we develop a clinical study of the fetoplacental circulation (encompassing umbilical and chorionic arteries) under the FGR condition, utilizing a combination of numerical and experimental approaches to quantify biomechanical and morphological characteristics. Placental samples from normal (n = 5) and FGR pregnancies (n = 5) underwent biomechanical testing (ring-opening and ring-tensile tests) under physiological conditions. Biomechanical behavior, including material properties and residual stress, was characterized via numerical analysis using a hyperelastic model and a simulation of the ring-closure process. Morphological analysis, including wall thickness and layer area measurements, was performed to relate structural features to biomechanical behavior. The umbilical and chorionic arteries exhibit distinct responses to FGR: the umbilical artery undergoes both morphological remodeling and changes in biomechanical properties, whereas the chorionic artery primarily shows biomechanical alterations. Overall, this study provides novel biomechanical evidence of the impact of FGR on placental vasculature, highlighting the complex interplay between morphology and mechanics in fetoplacental blood vessels.

Hypoxia plays a critical role in regulating vascular function, with endothelial mechanosensitive proteins, such as the piezo-type mechanosensitive ion channel component 1 (Piezo1), emerging as key players in maintaining vascular homeostasis. Piezo1 is essential for nitric oxide-mediated vasodilation and vascular tone regulation. However, the impact of hypoxia on endothelial Piezo1 expression and function remains poorly understood. The present study investigated the regulation of Piezo1 and mechanosensitive-related genes (MRGs) during hypoxic development and their role in fetal growth restriction (FGR). Using publicly available datasets, we identified distinct transcriptional profiles in placental endothelial cells from human FGR pregnancies and human umbilical vein endothelial cells (HUVEC) exposed to hypoxia. Functional enrichment analysis revealed significant changes in pathways related to PI3K-Akt, MAPK, and VEGF signaling and responses to mechanical stimuli. Hypoxia-related transcription factors, particularly HIF-1α and HIF-1β, were enriched in the promoter regions of differentially expressed MRGs, including Piezo1, suggesting a conserved regulatory mechanism. In vitro experiments confirmed hypoxia-induced down-regulation of Piezo1 in HUVEC, while ex vivo studies using a chicken embryo model demonstrated impaired Piezo1-mediated vasodilation following hypoxic development. Combined, these findings highlight the critical role of hypoxia in modulating endothelial Piezo1 expression and function, providing mechanistic insights into vascular dysfunction associated with FGR. The present study provides evidence for the potential to target Piezo1 and HIF-1α signaling as therapeutic strategies to improve vascular outcomes in offspring of pregnancies complicated by hypoxia and FGR.

The chronic hypoxia experienced by high-altitude residents profoundly impacts pregnancy, influencing maternal health, placental function, and the growth and development of the fetus. Exposure to chronic hypoxia during pregnancy increases the risk of complications like preeclampsia and fetal growth restriction and has lasting effects on offspring, extending from infancy to adulthood. Understanding how chronic hypoxia alters physiological adaptations to pregnancy and pregnancy outcomes is essential for high-altitude populations and for gaining broader insights into the mechanisms underlying reduced fetoplacental oxygenation in complicated pregnancy at sea level. This review summarizes current knowledge on physiological adaptations during pregnancy under hypoxic conditions. We describe key studies on the effects of high altitude and chronic hypoxia on pregnancy and examine the maternal, placental, fetal, and long-term physiological consequences. Finally, we review preclinical and clinical studies aimed at identifying interventions that could prevent or alleviate the adverse effects of chronic hypoxia on pregnancy outcomes and beyond.

Eccentric exercise-induced muscle damage (EIMD) impairs muscle function and recovery. While omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation has shown promise in mitigating EIMD, the role of their oxidation products (oxylipins) remains unclear. This study investigated the effects of 8-week n-3 PUFA supplementation on muscle recovery and its relationship with blood oxylipin profiles after EIMD in healthy men. Eighteen participants were randomly assigned into two groups: OMEGA (n = 9 28.0 ± 2.5 y; 2.5 g/d of DHA and 0.5 g/d of EPA) and PLACEBO (n = 9 21.4 ± 0.6 y; maltodextrin). Participants performed one bout of 100 unilateral isokinetic eccentric maximal voluntary contractions of the knee extensor muscles before and after an 8-week supplementation period. N-3 PUFA supplementation augmented plasma EPA- and DHA-derived oxylipins (p < 0.05) in the OMEGA group, which showed an attenuation of peak muscle maximum voluntary contraction loss (-15.4 ± 5.2%; p = 0.05) post-exercise compared to the PLACEBO group (1.3 ± 6.0%). There were no differences in muscles soreness between groups. Multivariate analyses identified body fat percentage and specific n-3 and n-6 PUFA-derived oxylipins as predictors of MVC loss after EIMD. In conclusion, the increased plasma levels of n-3 PUFA derived oxylipins following supplementation suggest a possible role for these lipid mediators in promoting muscle recovery.

Background: Obesity during pregnancy is related to adverse maternal and neonatal outcomes. Factors involved in these outcomes may include increased maternal insulin resistance, inflammation, oxidative stress, and nutrient mishandling. The placenta is the primary determinant of fetal outcomes, and its function can be impacted by maternal obesity. The aim of this study on mice was to determine the effect of obesity on maternal lipid handling, inflammatory and redox state, and placental oxidative stress, inflammatory signaling, and gene expression relative to female and male fetal growth. Methods: Female mice were fed control or obesogenic high-fat/high-sugar diet (HFHS) from 9 weeks prior to, and during, pregnancy. On day 18.5 of pregnancy, maternal plasma, and liver, placenta, and fetal serum were collected to examine the immune and redox states. The placental labyrinth zone (Lz) was dissected for RNA-sequencing analysis of gene expression changes. Results: the HFHS diet induced, in the dams, hepatic steatosis, oxidative stress (reduced catalase, elevated protein oxidation) and the activation of pro-inflammatory pathways (p38-MAPK), along with imbalanced circulating cytokine concentrations (increased IL-6 and decreased IL-5 and IL-17A). HFHS fetuses were asymmetrically growth-restricted, showing sex-specific changes in circulating cytokines (GM-CSF, TNF-α, IL-6 and IFN-γ). The morphology of the placenta Lz was modified by an HFHS diet, in association with sex-specific alterations in the expression of genes and proteins implicated in oxidative stress, inflammation, and stress signaling. Placental gene expression changes were comparable to that seen in models of intrauterine inflammation and were related to a transcriptional network involving transcription factors, LYL1 and PLAG1. Conclusion: This study shows that fetal growth restriction with maternal obesity is related to elevated oxidative stress, inflammatory pathways, and sex-specific placental changes. Our data are important, given the marked consequences and the rising rates of obesity worldwide.

Fetal growth restriction (FGR) is a common outcome in human suboptimal gestation and is related to prenatal origins of cardiovascular dysfunction in offspring. Despite this, therapy of human translational potential has not been identified. Using human umbilical and placental vessels and the chicken embryo model, we combined cellular, molecular, and functional studies to determine whether N-acetylcysteine (NAC) and hydrogen sulphide (H2S) protect cardiovascular function in growth-restricted unborn offspring. In human umbilical and placental arteries from control or FGR pregnancy and in vessels from near-term chicken embryos incubated under normoxic or hypoxic conditions, we determined the expression of the H2S gene CTH (i.e. cystathionine γ-lyase) (via quantitative PCR), the production of H2S (enzymatic activity), the DNA methylation profile (pyrosequencing) and vasodilator reactivity (wire myography) in the presence and absence of NAC treatment. The data show that FGR and hypoxia increased CTH expression in the embryonic/fetal vasculature in both species. NAC treatment increased aortic CTH expression and H2S production and enhanced third-order femoral artery dilator responses to the H2S donor sodium hydrosulphide in chicken embryos. NAC treatment also restored impaired endothelial relaxation in human third-to-fourth order chorionic arteries from FGR pregnancies and in third-order femoral arteries from hypoxic chicken embryos. This NAC-induced protection against endothelial dysfunction in hypoxic chicken embryos was mediated via nitric oxide independent mechanisms. Both developmental hypoxia and NAC promoted vascular changes in CTH DNA and NOS3 methylation patterns in chicken embryos. Combined, therefore, the data support that the effects of NAC and H2S offer a powerful mechanism of human translational potential against fetal cardiovascular dysfunction in complicated pregnancy. KEY POINTS: Gestation complicated by chronic fetal hypoxia and fetal growth restriction (FGR) increases a prenatal origin of cardiovascular disease in offspring, increasing interest in antenatal therapy to prevent against a fetal origin of cardiovascular dysfunction. We investigated the effects between N-acetylcysteine (NAC) and hydrogen sulphide (H2S) in the vasculature in FGR human pregnancy and in chronically hypoxic chicken embryos. Combining cellular, molecular, epigenetic and functional studies, we show that the vascular expression and synthesis of H2S is enhanced in hypoxic and FGR unborn offspring in both species and this acts to protect their vasculature. Therefore, the NAC/H2S pathway offers a powerful therapeutic mechanism of human translational potential against fetal cardiovascular dysfunction in complicated pregnancy.

Advances in understanding gene expression regulation through epigenetic mechanisms have contributed to elucidating the regulatory mechanisms of noncoding RNAs as pharmacological targets in several diseases. MicroRNAs (miRs) are a class of evolutionarily conserved, short, noncoding RNAs regulating in a concerted manner gene expression at the post-transcriptional level by targeting specific sequences of the 3'-untranslated region of mRNA. Conversely, mechanisms of cardiovascular disease (CVD) remain largely elusive due to their life-course origins, multifactorial pathophysiology, and co-morbidities. In this regard, CVD treatment with conventional medications results in therapeutic failure due to progressive resistance to monotherapy, which overlooks the multiple factors involved, and reduced adherence to poly-pharmacology approaches. Consequently, considering its role in regulating complete gene pathways, miR-based drugs have appreciably progressed into preclinical and clinical testing. This review summarizes the current knowledge about the mechanisms of miRs in cardiovascular disease, focusing specifically on describing how clinical chemistry and physics have improved the stability of the miR molecule. In addition, a comprehensive review of the main miRs involved in cardiovascular disease and the clinical trials in which these molecules are used as active pharmacological molecules is provided.

INTRODUCTION:Maternal obesity alters the immune function in the offspring. We hypothesize that maternal obesity and pro-inflammatory pathways induce leptin-related genes in neonatal monocytes, whereby high leptin levels enhance their inflammatory response. METHODS:Transcriptional profiles of cord blood leukocytes (CBL) in basal and pro-inflammatory conditions were studied to determine differentially expressed genes (DEG). The DNA methylation profile of CB monocytes (CBM) of neonates born to control BMI mothers and women with obesity was assayed to identify differentially methylated probes (DMP). CBM-derived macrophages were cultured with or without leptin (10-100 ng/ml) and then stimulated with lipopolysaccharide (LPS, 100 ng/ml) and interferon-gamma (20 ng/ml) to assess the induction of TNF-α and IL-10 transcripts. RESULTS:CBL from pregnancies with obesity (CBL-Ob) showed 12,183 DEG, affecting 49 out of 78 from the leptin pathway. Control CBM exposed to LPS showed 45 leptin-related DEG, an effect prevented by the co-exposure to LPS and IL-10. Conversely, CBM-Ob showed 5279 DMP enriched in insulin- and leptin-related genes, and Lasso regression of leptin-related DMP showed high predictive value for plasma leptin levels (r2 = 0.9897) and maternal BMI categories (AUC = 1). Chronic exposure to leptin increased TNF-α and decreased IL-10 levels in control BMI samples but not in Ob-CBM. Enhanced TNF-α induction after proinflammatory stimulation was observed in leptin-treated control BMI samples. DISCUSSION:Obesity in pregnancy is associated with a distinctive expression and DNA methylation profile of leptin-related genes in cord blood monocytes, meanwhile, leptin enhances the expression of pro-inflammatory cytokines upon stimulation with M1-skewing agents.

High-altitude (>2,500 m) residence increases the risk of pregnancy vascular disorders such as fetal growth restriction and preeclampsia, each characterized by impaired placental function. Genetic attributes of highland ancestry confer relative protection against vascular disorders of pregnancy at high altitudes. Although ion channels have been implicated in placental function regulation, neither their expression in high-altitude placentas nor their relationship to high-altitude preeclampsia has been determined. Here, we measured the expression of 26 ion-channel genes in placentas from preeclampsia cases and normotensive controls in La Paz, Bolivia (3,850 m). In addition, we correlated gene transcription to maternal and infant ancestry proportions. Gene expression was assessed by PCR, genetic ancestry evaluated by ADMIXTURE, and ion channel proteins localized by immunofluorescence. In preeclamptic placentas, 11 genes were downregulated (ABCC9, ATP2A2, CACNA1C, KCNE1, KCNJ8, KCNK3, KCNMA1, KCNQ1, KCNQ4, PKD2, and TRPV6) and two were upregulated (KCNQ3 and SCNN1G). KCNE1 expression was positively correlated with high-altitude Amerindian ancestry and negatively correlated with non-high altitude. SCNN1G was negatively correlated with African ancestry, despite minimal African admixture. Most ion channels were localized in syncytiotrophoblasts (Cav1.2, TRPP2, TRPV6, and Kv7.1), whereas expression of Kv7.4 was primarily in microvillous membranes, Kir6.1 in chorionic plate and fetal vessels, and MinK in stromal cells. Our findings suggest a role for differential placental ion channel expression in the development of preeclampsia. Functional studies are needed to determine processes affected by these ion channels in the placenta and whether therapies directed at modulating their activity could influence the onset or severity of preeclampsia.

Background: Biometrical and blood flow examinations are fundamental for assessing fetoplacental development during pregnancy. Guinea pigs have been proposed as a good model to study fetal development and related gestational complications; however, longitudinal growth and blood flow changes in utero have not been properly described. This study aimed to describe fetal and placental growth and blood flow of the main intrauterine vascular beds across normal guinea pig pregnancy and to discuss the relevance of this data for human pregnancy. Methods: Pregnant guinea pigs were studied from day 25 of pregnancy until term (day ~70) by ultrasound and Doppler assessment. The results were compared to human data from the literature. Results: Measurements of biparietal diameter (BPD), cranial circumference (CC), abdominal circumference, and placental biometry, as well as pulsatility index determination of umbilical artery, middle cerebral artery (MCA), and cerebroplacental ratio (CPR), were feasible to determine across pregnancy, and they could be adjusted to linear or nonlinear functions. In addition, several of these parameters showed a high correlation coefficient and could be used to assess gestational age in guinea pigs. We further compared these data to ultrasound variables from human pregnancy with high similarities. Conclusions: BPD and CC are the most reliable measurements to assess fetal growth in guinea pigs. Furthermore, this is the first report in which the MCA pulsatility index and CPR are described across guinea pig gestation. The guinea pig is a valuable model to assess fetal growth and blood flow distribution, variables that are comparable with human pregnancy.

PIEZO1 is a mechanosensitive cation channel implicated in shear stress-mediated endothelial-dependent vasorelaxation. Since altered shear stress patterns induce a pro-inflammatory endothelial environment, we analyzed transcriptional profiles of human endothelial cells to determine the effect of altered shear stress patterns and subsequent prooxidant and inflammatory conditions on PIEZO1 and mechanosensitive-related genes (MRG). In silico analyses were validated in vitro by assessing PIEZO1 transcript levels in both the umbilical artery (HUAEC) and vein (HUVEC) endothelium. Transcriptional profiling showed that PIEZO1 and some MRG associated with the inflammatory response were upregulated in response to high (15 dyn/cm2) and extremely high shear stress (30 dyn/cm2) in HUVEC. Changes in PIEZO1 and inflammatory MRG were paralleled by p65 but not KLF or YAP1 transcription factors. Similarly, PIEZO1 transcript levels were upregulated by TNF-alpha (TNF-α) in diverse endothelial cell types, and pre-treatment with agents that prevent p65 translocation to the nucleus abolished PIEZO1 induction. ChIP-seq analysis revealed that p65 bonded to the PIEZO1 promoter region, an effect increased by the stimulation with TNF-α. Altogether this data showed that NF-kappa B activation via p65 signaling regulates PIEZO1 expression, providing a new molecular link for prooxidant and inflammatory responses and mechanosensitive pathways in the endothelium.

La actividad física y ejercicio físico durante la gestación entregan beneficios tanto para la madre, al disminuir el riesgo de desarrollar condiciones como preeclampsia y diabetes gestacional, como para el feto, disminuyendo condiciones como la macrosomía y morbilidad respiratoria llevando a mejorar el resultado perinatal. Del mismo modo, una mejor condición física se asocia a resultados perinatales favorables. A nivel mundial, existen una serie de recomendaciones sobre los niveles de actividad física necesarios para obtener estos beneficios. La mayoría coincide en que se deben alcanzar al menos 150 minutos de actividad física moderada a la semana. A pesar de esto, la actividad física, el ejercicio y la condición física durante la gestación han sido poco explorados en Chile, existiendo una brecha en el conocimiento respecto a este tema. El objetivo de esta revisión es recopilar la evidencia disponible en Chile sobre actividad física, ejercicio y condición física durante la gestación, identificando las principales brechas de conocimiento respecto a este tema. Palabras clave: Actividad física, gestación, condición física. Abstract. Physical activity and exercise during pregnancy are beneficial for the mother, reducing the risk of developing conditions such as preeclampsia and gestational diabetes, as well as for the fetus by decreasing complications such as fetal macrosomia and respiratory outcomes, leading to an improved perinatal outcome. In the same way, a better physical fitness is associated to better perinatal outcomes. Worldwide, there are several recommendations regarding the appropriate physical activity levels necessary to obtain these benefits. Most agree that at least 150 minutes of moderate physical activity per week should be achieved. Despite this, physical activity, exercise, and physical fitness during pregnancy have been poorly explored in Chile, and thus there is a gap in knowledge on this subject. This review aims to compile the evidence available in Chile on physical activity, exercise, and physical fitness during pregnancy, identifying the main knowledge gaps on this topic. Keywords: Physical activity, pregnancy, fitness.