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1.
Cartilage ; : 19476035241241930, 2024 Apr 14.
Article in English | MEDLINE | ID: mdl-38616342

ABSTRACT

OBJECTIVES: While substantial progress has been made in engineering cartilaginous constructs for animal models, further research is needed to translate these methodologies for human applications. Evidence suggests that cultured autologous chondrocytes undergo changes in phenotype and gene expression, thereby affecting their proliferation and differentiation capacity. This study was designed to evaluate the expression of chondrogenic markers in cultured human articular chondrocytes from passages 3 (P3) and 7 (P7), beyond the current clinical recommendation of P3. METHODS: Cultured autologous chondrocytes were passaged from P3 up to P7, and quantitative polymerase chain reaction (qPCR) was used to assess mRNA expression of chondrogenic markers, including collagen type I (COLI), collagen type II (COLII), aggrecan (AGG), bone morphogenetic protein 4 (BMP4), transcription factor SOX-9 (SOX9), proteoglycan 4 (PGR4), and transformation-related protein 53 (p53), between P3 and P7. RESULTS: Except for AGG, no significant differences were found in the expression of markers between passages, suggesting the maintenance of chondrogenic potential in cultured chondrocytes. Differential expression identified between SOX9 and PGR4, as well as between COLI and SOX9, indicates that differences in chondrogenic markers are present between age groups and sexes, respectively. CONCLUSIONS: Overall, expression profiles of younger and male chondrocytes exhibit conversion of mature cartilage characteristics compared to their counterparts, with signs of dedifferentiation and loss of phenotype within-group passaging. These results may have implications in guiding the use of higher passaged chondrocytes for engineering constructs and provide a foundation for clinical recommendations surrounding the repair and treatment of articular cartilage pathology in both sexes.

2.
J Anat ; 244(6): 1093-1101, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38267217

ABSTRACT

The etiology of sirenomelia is currently unknown. Data are limited in comparing external and internal abnormalities using modern imaging technologies and molecular genetic analysis. The purpose of the current study was designed to compare external and internal anatomical defects in two cases of sirenomelia and Potter's sequence. Considered rare, Potter's sequence is a fetal disorder with characteristic features of bilateral renal agenesis, obstructive uropathy, atypical facial appearance, and limb malformations. The internal and external malformations of two term fetuses with sirenomelia and Potter's sequence were compared using assessment of external features, radiography and MRI on internal structures, and molecular genetic studies on sex determination. Data reveal that both fetuses were male and manifested with an overlapping but distinct spectrum of abnormalities. Principal differences were noted in the development of the ears, brain, urogenital system, lower limbs, pelvis, and vertebral column. Defects of the axial mesoderm are likely to underlie the abnormalities seen in both fetuses. The first one, which had only caudal defects, was found to have a spectrum of abnormalities most similar to those associated with more severe forms of the small pelvic outlet syndrome, although the structure and orientation of the sacrum and iliae were different from previously reported cases. The other had both caudal and cranial defects, and was most similar to those described in the axial mesodermal dysplasia syndrome. Defects associated with sirenomelia can be evaluated with standard gross anatomy examination, radiology, MRI, and modified PCR techniques to determine anatomical abnormalities and the sex of preserved specimens, respectively. Evidence indicated that sirenomelia could be developed via various etiologies.


Subject(s)
Ectromelia , Humans , Male , Ectromelia/genetics , Ectromelia/diagnostic imaging , Ectromelia/pathology , Female , Magnetic Resonance Imaging , Abnormalities, Multiple/genetics , Abnormalities, Multiple/diagnostic imaging , Pregnancy , Fetus/abnormalities , Fetus/diagnostic imaging
3.
POCUS J ; 8(1): 81-87, 2023.
Article in English | MEDLINE | ID: mdl-37152346

ABSTRACT

Point of care Ultrasound (POCUS) has been adopted into clinical practice across many fields of medicine. Undergraduate medical education programs have recognized the need to incorporate POCUS training into their curricula, traditionally done in small groups with in-person sessions. This method is resource intensive and requires sufficient equipment and expertise. These requirements are often cited as barriers for implementation. During the Coronavirus Disease 2019 (COVID-19) pandemic, POCUS education was required to adapt to physical distancing regulations, giving rise to novel teaching methods for POCUS. This article outlines the implementation of a POCUS teaching session before and during the pandemic. It describes how these innovations can scale POCUS teaching and overcome barriers moving forward. A flipped classroom model was implemented for all learners. Learners were given an introductory POCUS module before the scheduled in-person or virtual teaching session. Sixty-nine learners participated in conventional in-person teaching, while twenty-two learners participated in virtual teaching following the pandemic-related restrictions. Learners completed a written test before and following the teaching. In-person learners were assessed using an objective structured assessment of ultrasound skills (OSAUS) pre- and post-learning sessions. A follow-up survey was conducted three years after the teaching sessions were completed. Both in-person and virtual groups demonstrated statistically significant improvement in knowledge scores (p <0.0001). Both groups had similar post-test learning scores (74.2 ± 13.6% vs. 71.8 ± 14.5 %, respectively). On follow-up questionnaires, respondents indicate that they found our online and in-person modes of teaching helpful during their residency. POCUS education continues to face a variety of barriers, including limitations in infrastructure and expertise. This study describes an adapted POCUS teaching model that is scalable, uses minimal infrastructure and retains the interactivity of conventional small-group POCUS teaching. This program can serve as a blueprint for other institutions offering POCUS teaching, especially when conventional teaching methods are limited.

4.
Atherosclerosis ; 374: 1-10, 2023 06.
Article in English | MEDLINE | ID: mdl-37149970

ABSTRACT

As the global burden of atherosclerotic cardiovascular disease continues to rise, there is an increased demand for improved imaging techniques for earlier detection of atherosclerotic plaques and new therapeutic targets. Plaque lesions, vulnerable to rupture and thrombosis, are thought to be responsible for the majority of cardiovascular events, and are characterized by a large lipid core, a thin fibrous cap, and neovascularization. In addition to supplying the plaque core with increased inflammatory factors, these pathological neovessels are tortuous and leaky, further increasing the risk of intraplaque hemorrhage. Clinically, plaque neovascularization has been shown to be a significant and independent predictor of adverse cardiovascular outcomes. Microvessels can be detected through contrast-enhanced ultrasound (CEUS) imaging, however, clinical assessment in vivo is generally limited to qualitative measures of plaque neovascularization. There is no validated standard for quantitative assessment of the microvessel networks found in plaques. Advances in our understanding of the pathological mechanisms underlying plaque neovascularization and its significant role in the morbidity and mortality associated with atherosclerosis have made it an attractive area of research in translational medicine. Current areas of research include the development of novel therapeutic and diagnostic agents to target plaque neovascularization stabilization. With recent progress in nanotechnology, nanoparticles have been investigated for their ability to specifically target neovascularization. Contrast microbubbles have been similarly engineered to carry loads of therapeutic agents and can be visualized using CEUS. This review summarizes the pathogenesis, diagnosis, clinical significance of neovascularization, and importantly the emerging areas of theranostic tool development.


Subject(s)
Atherosclerosis , Plaque, Atherosclerotic , Humans , Plaque, Atherosclerotic/pathology , Precision Medicine , Atherosclerosis/diagnostic imaging , Atherosclerosis/therapy , Atherosclerosis/pathology , Neovascularization, Pathologic , Ultrasonography
5.
J Clin Lipidol ; 17(3): 315-326, 2023.
Article in English | MEDLINE | ID: mdl-37173161

ABSTRACT

Intraplaque neovascularization (IPN), a key feature of vulnerable carotid plaque, is associated with adverse cardiovascular (CV) events. Statin therapy has been shown to diminish and stabilize atherosclerotic plaque, but its effect on IPN is uncertain. This review investigated the effects of common pharmacologic anti-atherosclerotic therapies on carotid IPN. Electronic databases (MEDLINE, EMBASE and Cochrane Library) were searched from inception until July 13, 2022. Studies evaluating the effect of anti-atherosclerotic therapy on carotid IPN among adults with carotid atherosclerosis were included. Sixteen studies were eligible for inclusion. Contrast-enhanced ultrasound (CEUS) was the most common IPN assessment modality (n=8), followed by dynamic contrast-enhanced MRI (DCE-MRI) (n=4), excised plaque histology (n=3) and superb microvascular imaging (n=2). In fifteen studies, statins were the therapy of interest and one study assessed PCSK9 inhibitors. Among CEUS studies, baseline statin use was associated with a lower frequency of carotid IPN (median OR = 0.45). Prospective studies showed regression of IPN after 6-12 months of lipid-lowering therapy, with more regression observed in treated participants compared to untreated controls. Our findings suggest that lipid-lowering therapy with statins or PCSK9 inhibitors is associated with IPN regression. However, there was no correlation between change in IPN parameters and change in serum lipids and inflammatory markers in statin-treated participants, so it is unclear whether these factors are mediators in the observed IPN changes. Lastly, this review was limited by study heterogeneity and small sample sizes, so larger trials are needed to validate findings.


Subject(s)
Carotid Artery Diseases , Carotid Stenosis , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Plaque, Atherosclerotic , Adult , Humans , Proprotein Convertase 9 , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Prospective Studies , PCSK9 Inhibitors , Contrast Media , Carotid Arteries/diagnostic imaging , Carotid Arteries/pathology , Carotid Artery Diseases/complications , Carotid Artery Diseases/drug therapy , Carotid Artery Diseases/pathology , Plaque, Atherosclerotic/diagnostic imaging , Plaque, Atherosclerotic/drug therapy , Plaque, Atherosclerotic/pathology , Ultrasonography , Lipids
6.
Surg Radiol Anat ; 44(10): 1349-1353, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36155834

ABSTRACT

PURPOSE: To contribute to the documentation and consideration of the prevalence of the atlantomastoid muscle in humans. METHODS: Sixty formalin-fixed cadaveric sides were dissected for the presence of the atlantomastoid muscle (2 sides per donor). Laterality, origin, insertion, and other observable characteristics of the variant were recorded along with donor sex for comparative analyses. RESULTS: The atlantomastoid muscle was observed in nine sides (15%): two left side only, three right side only, and 2 bilaterally. The origin of the muscle was consistent from the transverse process of the atlas, lateral to both the insertion of obliquus capitis inferior and the origin of obliquus capitis superior. In one instance, the origin of atlantomastoid was continuous with the most superior tendinous slip of levator scapulae. The insertion of each atlantomastoid variant was the mastoid process, however, the precise location was variable. CONCLUSION: The atlantomastoid muscle is a common accessory muscle of the suboccipital region; the muscle was present in 15% of the cadaveric sides dissected in this study. Despite the notable prevalence of atlantomastoid muscles, there is little current literature dedicated to its study. Here, we document the first new information related to the prevalence of atlantomastoid since 1964 and discuss the development and potential clinical significance of the muscle.


Subject(s)
Superficial Back Muscles , Humans , Cadaver , Cross-Sectional Studies , Head , Mastoid
8.
J Dev Orig Health Dis ; 13(6): 706-718, 2022 12.
Article in English | MEDLINE | ID: mdl-35593438

ABSTRACT

Children of women with pre-eclampsia have increased risk of cardiovascular (CV) and metabolic disease in adult life. Furthermore, the risk of pregnancy complications is higher in daughters born to women affected by pre-eclampsia than in daughters born after uncomplicated pregnancies. While aberrant inflammation contributes to the pathophysiology of pregnancy complications, including pre-eclampsia, the contribution of maternal inflammation to subsequent risk of CV and metabolic disease as well as pregnancy complications in the offspring remains unclear. Here, we demonstrate that 24-week-old female rats (F1) born to dams (F0) exposed to lipopolysaccharide (LPS) during pregnancy (to induce inflammation) exhibited mild systolic dysfunction, increased cardiac growth-related gene expression, altered glucose tolerance, and coagulopathy; whereas male F1 offspring exhibited altered glucose tolerance and increased visceral fat accumulation compared with F1 sex-matched offspring born to saline-treated dams. Both male and female F1 offspring born to LPS-treated dams had evidence of anemia. Fetuses (F2) from F1 females born to LPS-treated dams were growth restricted, and this reduction in fetal growth was associated with increased CD68 positivity (indicative of macrophage presence) and decreased expression of glucose transporter-1 in their utero-placental units. These results indicate that abnormal maternal inflammation can contribute to increased risk of CV and metabolic disease in the offspring, and that the effects of inflammation may cross generations. Our findings provide evidence in support of early screening for CV and metabolic disease, as well as pregnancy complications in offspring affected by pre-eclampsia or other pregnancy complications associated with aberrant inflammation.


Subject(s)
Cardiovascular Diseases , Pre-Eclampsia , Prenatal Exposure Delayed Effects , Humans , Rats , Female , Pregnancy , Male , Animals , Fetal Growth Retardation , Pre-Eclampsia/etiology , Placenta/metabolism , Lipopolysaccharides/metabolism , Inflammation/metabolism , Cardiovascular Diseases/metabolism , Glucose/metabolism
10.
Biotechnol Bioeng ; 118(10): 4119-4128, 2021 10.
Article in English | MEDLINE | ID: mdl-34265075

ABSTRACT

A major shortcoming in cartilage tissue engineering is the low biosynthetic response of chondrocytes. While different strategies have been investigated, a novel approach may be to control nutrient metabolism. Although known for their anaerobic metabolism, chondrocytes are more synthetically active under conditions that elicit mixed aerobic-anaerobic metabolism. Here, we postulate this metabolic switch induces HIF-1α signaling resulting in improved growth. Transition to different metabolic states can result in the pooling of metabolites, several of which can stabilize HIF-1α by interfering with PHD2. Chondrocytes cultured under increased media availability accelerated tissue deposition with the greatest effect occurring at 2 ml/106 cells. Under higher media availability, metabolism switched from anaerobic to mixed aerobic-anaerobic. Around this transition, maximal changes in PHD2 activity, HIF-1α expression, and HIF-1 target gene expression were observed. Loss-of-function studies using YC-1 confirmed the involvement of HIF-1. Lastly, targeted metabolomic studies revealed that intracellular lactate and succinate correlated with PHD2 activity. This study demonstrates that cartilaginous tissue formation can be regulated by nutrient metabolism and that this response is mediated through changes in HIF-1α signaling. By harnessing this newly identified metabolic switch, engineered cartilage implants may be developed without the need for sophisticated methods which could aid translation to the clinic.


Subject(s)
Cartilage/metabolism , Chondrocytes/metabolism , Signal Transduction , Animals , Cartilage/cytology , Cattle , Cell Hypoxia , Chondrocytes/cytology , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Hypoxia-Inducible Factor-Proline Dioxygenases/metabolism
11.
J Am Soc Echocardiogr ; 34(11): 1184-1194, 2021 11.
Article in English | MEDLINE | ID: mdl-34129920

ABSTRACT

BACKGROUND: Intraplaque neovascularization (IPN) in advanced lesions of the carotid artery has been linked to plaque progression and risk of rupture. Quantitative measurement of IPN may provide a more powerful tool for the detection of such "vulnerable" plaque than the current visual scoring method. The aim of this study was to develop a phantom platform of a neovascularized atherosclerotic plaque within a carotid artery to assess new methods of quantifying IPN. METHODS: Ninety-two synthetic plaque models with various IPN architectures representing different ranges of IPN scoring were created and assessed using contrast-enhanced ultrasound. Intraplaque neovascularization volume was calculated from contrast infiltration in B mode. The plaque models were used to develop a testing platform for IPN quantification. A neovascularized enhancement ratio (NER) was calculated using commercially available software. The plaque model NERs were then compared to human plaque NERs (n = 42) to assess score relationship. Parametric mapping of dynamic intensity over time was used to differentiate IPN from calcified plaque regions. RESULTS: A positive correlation between NER and IPN volume (rho = 0.45; P < .0001) was found in the plaque models. Enhancement of certain plaque model types showed that they resembled human plaques, with visual grade scores of 0 (NER mean difference = 1.05 ± SE 2.45; P = .67), 1 (NER mean difference = 0.22 ± SE 3.26; P = .95), and 2 (NER mean difference = -0.84 ± SE 3.33; P = .80). An optimal cutoff for NER (0.355) identified grade 2 human plaques with a sensitivity of 95% and specificity of 91%. CONCLUSIONS: We developed a carotid artery model of neovascularized plaque and established a quantitative method for IPN using commercially available technology. We also developed an analysis method to quantify IPN in calcified plaques. This novel tool has the potential to improve clinical identification of vulnerable plaques, providing objective measures of IPN for cardiovascular risk assessment.


Subject(s)
Carotid Stenosis , Plaque, Atherosclerotic , Carotid Arteries/diagnostic imaging , Carotid Stenosis/diagnosis , Carotid Stenosis/diagnostic imaging , Contrast Media , Humans , Neovascularization, Pathologic/diagnostic imaging , Plaque, Atherosclerotic/diagnostic imaging , Ultrasonography
12.
Clin Anat ; 32(2): 224-230, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30281854

ABSTRACT

The adverse effects formaldehyde fixation has on tissues both gross anatomically and histologically are well documented. Consequently, researchers are seeking alternative embalming techniques that better preserve in vivo characteristics of tissues. Phenol-based embalming is one method that has shown promise in its ability to adequately preserve the in vivo qualities of tissues through preliminary explorations at the gross anatomical level. The literature on phenol-based embalming is currently scarce, especially with regard to its effects on tissues at the microscopic level. For the current study we aimed to document the histologic effects of a formaldehyde-free phenol-based embalming solution on neural tissue, with the hope of providing novel insight into the effects of soft-embalming on tissues at the microscopic level. Cerebral and cerebellar tissue obtained from porcine brains was fixed in phenol- and formaldehyde-based fixatives; the latter served as a control. Fixed samples were processed for histological analysis. The phenol-based embalming solution provided excellent preservation of the cerebral and cerebellar tissue morphology. Of note was the decrease in separation artifact seen in both tissue types relative to the control tissue, as well as anomalous circular artifacts in the white matter. The results of this study indicate that the phenol-based embalming solution preserves neural tissue at the histological level, perhaps superiorly in many aspects when compared to the formaldehyde-fixed samples. Further investigations of both gross anatomy and histology are recommended on the basis of these promising new findings to determine its potential utilities within research and education. Clin. Anat. 32:224-230, 2019. © 2018 Wiley Periodicals, Inc.


Subject(s)
Fixatives/pharmacology , Formaldehyde/pharmacology , Nerve Tissue/drug effects , Phenol/pharmacology , Preservation, Biological/methods , Animals , Cerebellum/drug effects , Cerebral Cortex/drug effects , Fixatives/adverse effects , Formaldehyde/adverse effects , Swine
13.
Mol Cell Biochem ; 449(1-2): 227-236, 2018 Dec.
Article in English | MEDLINE | ID: mdl-29802597

ABSTRACT

Pregnancy evokes many challenges on the maternal cardiovascular system that may unmask predispositions for future disease. This is particularly evident for women who develop pregnancy-related disorders, for example, pre-eclampsia and gestational diabetes or hypertension. Such pregnancy-related syndromes increase the risk for cardiovascular disease (CVD) postpartum. As a result, pregnancy has been termed as a cardiovascular stress test and an indicator or marker to predict the development of CVD later in life. In addition, pregnancy-related disorders impact the development of offspring also placing them at a higher risk for disease. Utilizing pregnancy as a physiological stressor, the current investigation sought to determine whether the cardiovascular system of offspring exposed to gestational hypertension in utero would respond adversely to the stress of pregnancy. Heterozygous atrial natriuretic peptide gene-disrupted (ANP+/-) offspring were generated by either crossing male wildtype ANP+/+ with female knockout ANP-/- to produce ANP+/-KO mice or crossing female wildtype ANP+/+ with male knockout ANP-/- to produce ANP+/-WT mice. To study the cardiovascular stress induced by pregnancy, female ANP+/-WT and ANP+/-KO mice were mated with male wildtype ANP+/+ mice to initiate pregnancy. Cardiac size and molecular expression of the renin-angiotensin (RAS) and natriuretic peptide systems (NPS) were compared between offspring groups. Our data demonstrate that gestational hypertension and lack of maternal ANP did not significantly impact the progression and regression of pregnancy-induced cardiac hypertrophy over gestation and postpartum in ANP+/- offspring. Additionally, the molecular cardiac expression of the RAS and NPS did not differ between offspring groups. Future investigation should assess potential differences in cardiac function and the impact of fetal-programming on offspring cardiovascular adaptations during pregnancy in more severe models of pregnancy-related hypertensive syndrome such as angiotensin II or isoproterenol infusion.


Subject(s)
Atrial Natriuretic Factor/deficiency , Cardiomegaly , Pregnancy Complications, Cardiovascular , Animals , Cardiomegaly/genetics , Cardiomegaly/metabolism , Cardiomegaly/pathology , Disease Models, Animal , Female , Male , Mice , Mice, Knockout , Pregnancy , Pregnancy Complications, Cardiovascular/genetics , Pregnancy Complications, Cardiovascular/metabolism , Pregnancy Complications, Cardiovascular/pathology
14.
Int J Cardiovasc Imaging ; 34(7): 1081-1090, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29464422

ABSTRACT

The carotid bifurcation is a common site of atherosclerotic plaque. Plaque development is thought to occur preferentially at geometrically predisposed areas such as arterial branch points. The aim of this study was to investigate the geometric and anatomical variables that contribute to the development of carotid plaque using three-dimensional (3D) ultrasound. Sixty-seven consecutive outpatients referred for elective coronary angiography underwent 3D carotid ultrasound scans for the purpose of carotid plaque quantification. Geometric quantification of the left and right carotid bulbs were performed retrospectively on this study population. Geometric values such as angle, area and length of the carotid bulb and the bifurcation were determined using QLAB software (Philips Healthcare). Plaque volume within the carotid bulb and artery branches was quantified using the stacked contour method. Pearson's correlation and linear regression analysis were used to determine the relationship between anatomical variables and plaque volume. The mean age for the total patient population was 65.9 ± 11.5 years. Carotid bulb inflow area (BIA) (r = 0.28, p = 0.001), bulb volume (BV) (r = 0.21, p = 0.01) and bifurcation angle (BifA) (r = 0.18, p = 0.04) showed a positive linear relationship with plaque volume. In contrast, internal carotid artery angle (ICAA) (r = - 0.18, p = 0.04) and bulb flare (r = - 0.20, p = 0.02) displayed a negative linear relationship with plaque volume. When adjusting for age and sex, only the BIA remained significant (ß = 0.18, p = 0.04). Geometric variables were identified as potential risk factors associated with plaque volume in the carotid bulb. Further analysis of the evolution of the BIA as well as the relationship to other geometric variables could create a stronger predictive model of atherosclerosis as well as assist in preoperative planning.


Subject(s)
Carotid Arteries/diagnostic imaging , Carotid Artery Diseases/diagnostic imaging , Plaque, Atherosclerotic/diagnostic imaging , Ultrasonography/methods , Aged , Carotid Arteries/pathology , Carotid Artery Diseases/pathology , Coronary Angiography , Female , Humans , Imaging, Three-Dimensional , Male , Middle Aged , Organ Size , Plaque, Atherosclerotic/pathology , Predictive Value of Tests , Retrospective Studies
15.
Tissue Eng Part A ; 24(5-6): 369-381, 2018 03.
Article in English | MEDLINE | ID: mdl-28548569

ABSTRACT

Low collagen accumulation in the extracellular matrix is a pressing problem in cartilage tissue engineering, leading to a low collagen-to-glycosaminoglycan (GAG) ratio and poor mechanical properties in neocartilage. Soluble factors have been shown to increase collagen content, but may result in a more pronounced increase in GAG content. Thyroid hormones have been reported to stimulate collagen and GAG production, but reported outcomes, including which specific collagen types are affected, are variable throughout the literature. Here we investigated the ability of thyroxine (T4) to preferentially stimulate collagen production, as compared with GAG, in articular chondrocyte-derived scaffold-free engineered cartilage. Dose response curves for T4 in pellet cultures showed that 25 ng/mL T4 increased the total collagen content without increasing the GAG content, resulting in a statistically significant increase in the collagen-to-GAG ratio, a fold change of 2.3 ± 1.2, p < 0.05. In contrast, another growth factor, TGFß1, increased the GAG content in excess of threefold more than the increase in collagen. In large scaffold-free neocartilage, T4 also increased the total collagen/DNA at 1 month and at 2 months (fold increases of 2.1 ± 0.8, p < 0.01 and 2.1 ± 0.4, p < 0.001, respectively). Increases in GAG content were not statistically significant. The effect on collagen was largely specific to collagen type II, which showed a 2.8 ± 1.6-fold increase of COL2A1 mRNA expression (p < 0.01). Western blots confirmed a statistically significant increase in type II collagen protein at 1 month (fold increase of 2.2 ± 1.8); at 2 months, the fold increase of 3.7 ± 3.3 approached significance (p = 0.059). Collagen type X protein was less than the 0.1 µg limit of detection. T4 did not affect COL10A1 and COL1A2 gene expression in a statistically significant manner. Biglycan mRNA expression increased 2.6 ± 1.6-fold, p < 0.05. Results of this study show that an optimized dosage of T4 is able to increase collagen type II content, and do so preferential to GAG. Moreover, the upregulation of COL2A1 gene expression and type II collagen protein accumulation, without a concomitant increase in collagens type I or type X, signifies a direct enhancement of chondrogenesis of hyaline articular cartilage without the induction of terminal differentiation.


Subject(s)
Cartilage, Articular/metabolism , Chondrocytes/metabolism , Collagen Type II/biosynthesis , Gene Expression Regulation/drug effects , Thyroxine/pharmacology , Tissue Engineering , Animals , Cartilage, Articular/cytology , Chondrocytes/cytology , Dose-Response Relationship, Drug , Male , Rabbits
16.
Biol Reprod ; 97(1): 143-152, 2017 Jul 01.
Article in English | MEDLINE | ID: mdl-28859286

ABSTRACT

INTRODUCTION: Pre-eclampsia is associated with increased risk of subsequent cardiovascular and metabolic disease in the affected mothers. While aberrant inflammation contributes to the pathophysiology of pre-eclampsia, it is unclear whether maternal inflammation contributes to the increased risk of disease. Here, we determined the effect of aberrant inflammation in pregnancy on cardiovascular and metabolic disease risk factors. METHODS: Wistar rats were administered low doses of lipopolysaccharide (LPS) on gestational days (GD) 13.5-16.5 to induce inflammation. Controls included pregnant rats treated with saline and nonpregnant rats treated with LPS or saline. We previously showed that LPS-treated pregnant rats exhibit key features of pre-eclampsia. Echocardiographic parameters, heart weight, blood pressure, blood lipids, pulse-wave velocity, and glucose tolerance, were assessed at 16 weeks postpartum. Messenger RNA levels of transcription factors associated with cardiac growth were measured in left ventricular tissue; histone modifications and global DNA methylation were determined in hearts and livers at GD 17.5 and at 16 weeks postpartum. RESULTS: Compared with saline-treated pregnant rats and nonpregnant rats treated with LPS or saline, LPS-treated pregnant rats exhibited left ventricular hypertrophy and increased blood cholesterol and low-density lipoprotein levels at 16 weeks postdelivery. LPS-treated rats had increased left ventricular mRNA levels of hypertrophy-associated transcription factors at GD 17.5 and increased levels of modified histones in hearts and livers at GD 17.5 and 16 weeks postpartum. Other parameters remained unchanged. CONCLUSION: Aberrant inflammation during pregnancy results in persistent alterations in maternal physiological parameters and epigenetic modifications that could contribute to the pathophysiology of cardiovascular disease.


Subject(s)
Inflammation/chemically induced , Lipopolysaccharides/toxicity , Pregnancy Complications, Cardiovascular , Animals , Blood Pressure , DNA/genetics , DNA/metabolism , Echocardiography , Female , Gene Expression Regulation , Heart , Histones/genetics , Histones/metabolism , Inflammation/complications , Pregnancy , Rats , Rats, Wistar , Risk Factors
17.
Cardiol Res ; 8(1): 1-6, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28275418

ABSTRACT

BACKGROUND: Polymorphisms within natriuretic peptide (NP) genes have been associated with clinical outcomes for cardiovascular disease (CVD), but no previous study has compared the effect of these polymorphisms between men and women. This study aimed to investigate the association between single nucleotide polymorphisms (SNPs) in key genes of the NP system and coronary angiographic outcomes, with the focus on the sexual dimorphism in the effects of these SNPs. METHODS: Patients undergoing clinically indicated coronary angiography (n = 513, 328 men and 185 women) were consented and genotyped for NPPA rs5065, NPPB rs198389 and NPR2 rs10758325. Patients were stratified into having normal coronaries, non-obstructive coronary artery disease (CAD) or obstructive CAD, based on the highest stenosis in any epicardial artery. Average luminal narrowing across all four arteries was derived to represent the overall atherosclerotic burden. RESULTS: The frequency of NPPB rs198389 AA genotype was significantly higher in women with obstructive CAD (P = 0.014). The same association was not observed in males. With respect to atherosclerotic burden, an association was found between the AA genotype and average luminal narrowing in women (P = 0.005), but not in men. CONCLUSIONS: The current study identified an association between an SNP of the NPPB gene and coronary atherosclerotic burden through angiographic evidence in women but not in men. These results suggest that B-type natriuretic peptide (BNP) may have more important involvement in the development of CAD in women compared to men, and as such, genotyping of the NPPB gene may serve as a potential biomarker to identify women with high risk for CAD.

18.
Front Biosci (Schol Ed) ; 9(1): 46-54, 2017 01 01.
Article in English | MEDLINE | ID: mdl-27814573

ABSTRACT

Hypoxia and inflammatory cytokine activation (H&I) are common processes in many acute and chronic diseases. Thus, a single vector that responds to both hypoxia and inflammatory cytokines, such as TNF-alpha, is useful for assesing the severity of such diseases. Adaptation to hypoxia is regulated primarily by hypoxia inducible transcription factor (HIF alpha) nuclear proteins that engage genes containing a hypoxia response element (HRE). Inflammation activates a multitude of cytokines, including TNF-alpha, that invariably modulate activation of the nuclear factor kappa B (NF-kB) transcription factor. We constructed a vector that encompassed both a hypoxia response element (HRE), and a NF-kappaB responsive element. We show that this vector was functionally responsive to both hypoxia and TNF-alpha, in vitro and in vivo. Thus, this vector might be suitable for the detection and assessment of hypoxia or TNF-alpha.


Subject(s)
Cell Hypoxia/physiology , Genetic Vectors/genetics , NF-kappa B/genetics , Response Elements , Tumor Necrosis Factor-alpha/pharmacology , Animals , Cell Hypoxia/genetics , Cell Line, Tumor , HEK293 Cells , Humans , Male , Mice , Mice, Transgenic , NF-kappa B/metabolism , Promoter Regions, Genetic
19.
Biol Reprod ; 93(6): 142, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26536903

ABSTRACT

Pregnancy induces cardiovascular adaptations in response to increased volume overload. Aside from the hemodynamic changes that occur during pregnancy, the maternal heart also undergoes structural changes. However, cardiac modulation in pregnancies complicated by gestational hypertension is incompletely understood. The objectives of the current investigation were to determine the role of the natriuretic peptide (NP) system in pregnancy and to assess alterations in pregnancy-induced cardiac hypertrophy between gestationally hypertensive and normotensive dams. Previously we have shown that mice lacking the expression of atrial NP (ANP; ANP(-/-)) exhibit a gestational hypertensive phenotype. In the current study, female ANP(+/+) and ANP(-/-) mice were mated with ANP(+/+) males. Changes in cardiac size and weight were evaluated across pregnancy at Gestational Days 15.5 and 17.5 and Postnatal Days 7, 14, and 28. Nonpregnant mice were used as controls. Physical measurement recordings and histological analyses demonstrated peak cardiac hypertrophy occurring at 14 days postpartum in both ANP(+/+) and ANP(-/-) dams with little to no change during pregnancy. Additionally, left ventricular expression of the renin-angiotensin system (RAS) and NP system was quantified by real-time quantitative polymerase chain reaction. Up-regulation of Agt and AT(1a) genes was observed late in pregnancy, while Nppa and Nppb genes were significantly up-regulated postpartum. Our data suggest that pregnancy-induced cardiac hypertrophy may be influenced by the RAS throughout gestation and by the NP system postpartum. Further investigations are required to gain a complete understanding of the mechanistic aspects of pregnancy-induced cardiac hypertrophy.


Subject(s)
Atrial Natriuretic Factor/metabolism , Blood Pressure/physiology , Cardiomegaly/physiopathology , Hypertension, Pregnancy-Induced/physiopathology , Angiotensins/genetics , Angiotensins/metabolism , Animals , Atrial Natriuretic Factor/genetics , Cardiomegaly/metabolism , Disease Models, Animal , Female , Hypertension, Pregnancy-Induced/metabolism , Mice , Mice, Knockout , Pregnancy , Receptor, Angiotensin, Type 1/genetics , Receptor, Angiotensin, Type 1/metabolism , Renin-Angiotensin System/physiology , Up-Regulation
20.
Mol Cell Biochem ; 408(1-2): 223-33, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26169981

ABSTRACT

The maternal system is challenged with many physiological changes throughout pregnancy to prepare the body to meet the metabolic needs of the fetus and for delivery. Many pregnancies, however, are faced with pathological stressors or complications that significantly impact maternal health. A shift in this paradigm is now beginning to investigate the implication of pregnancy complications on the fetus and their continued influence on offspring disease risk into adulthood. In this investigation, we sought to determine whether maternal hypertension during pregnancy alters the cerebral response of adult offspring to acute ischemic stroke. Atrial natriuretic peptide gene-disrupted (ANP(-/-)) mothers exhibit chronic hypertension that escalates during pregnancy. Through comparison of heterozygote offspring born from either normotensive (ANP(+/-WT)) or hypertensive (ANP(+/-KO)) mothers, we have demonstrated that offspring exposed to maternal hypertension exhibit larger cerebral infarct volumes following middle cerebral artery occlusion. Observation of equal baseline cardiovascular measures, cerebrovascular structure, and cerebral blood volumes between heterozygote offspring suggests no added influences on offspring that would contribute to adverse cerebral response post-stroke. Cerebral mRNA expression of endothelin and nitric oxide synthase vasoactive systems demonstrated up-regulation of Et-1 and Nos3 in ANP(+/-KO) mice and thus an enhanced acute vascular response compared to ANP(+/-WT) counterparts. Gene expression of Na(+)/K(+) ATPase channel isoforms, Atp1a1, Atp1a3, and Atp1b1, displayed no significant differences. These investigations are the first to demonstrate a fetal programming effect between maternal hypertension and adult offspring stroke outcome. Further mechanistic studies are required to complement epidemiological evidence of this phenomenon in the literature.


Subject(s)
Atrial Natriuretic Factor/genetics , Cerebral Infarction/pathology , Hypertension, Pregnancy-Induced/genetics , Prenatal Exposure Delayed Effects/pathology , Adult Children , Animals , Cerebral Infarction/etiology , Cerebral Infarction/genetics , Disease Models, Animal , Endothelins/genetics , Female , Humans , Mice , Nitric Oxide Synthase/genetics , Pregnancy , Prenatal Exposure Delayed Effects/etiology , Prenatal Exposure Delayed Effects/genetics
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