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Blood pressure (BP) displays a circadian rhythm and disruptions in this pattern elevate cardiovascular risk. Although both central and peripheral clock genes are implicated in these processes, the importance of vascular clock genes is not fully understood. BP, vascular reactivity, and the renin-angiotensin-aldosterone system display overt sex differences, but whether changes in circadian patterns underlie these differences is unknown. Therefore, we hypothesized that circadian rhythms and vascular clock genes would differ across sex and would be blunted by angiotensin II (ANG II)-induced hypertension. ANG II infusion elevated BP and disrupted circadian patterns similarly in both males and females. In females, an impact on heart rate (HR) and locomotor activity was revealed, whereas in males hypertension suppressed baroreflex sensitivity (BRS). A marked disruption in the vascular expression patterns of period circadian regulator 1 (Per1) and brain and muscle aryl hydrocarbon receptor nuclear translocator like protein 1 (Bmal1) was noted in both sexes. Vascular expression of the G protein-coupled estrogen receptor (Gper1) also showed diurnal synchronization in both sexes that was similar to that of Per1 and Per2 and disrupted by hypertension. In contrast, vascular expression of estrogen receptor 1 (Esr1) showed a diurnal rhythm and hypertension-induced disruption only in females. This study shows a strikingly similar impact of hypertension on BP rhythmicity, vascular clock genes, and vascular estrogen receptor expression in both sexes. We identified a greater impact of hypertension on locomotor activity and heart rate in females and on baroreflex sensitivity in males and also revealed a diurnal regulation of vascular estrogen receptors. These insights highlight the intricate ties between circadian biology, sex differences, and cardiovascular regulation. NEW & NOTEWORTHY: This study reveals that ANG II-induced hypertension disrupts the circadian rhythm of blood pressure in both male and female mice, with parallel effects on vascular clock gene and estrogen receptor diurnal patterns. Notably, sex-specific responses to hypertension in terms of locomotor activity, heart rate, and baroreflex sensitivity are revealed. These findings pave the way for chronotherapeutic strategies tailored to mitigate cardiovascular risks associated with disrupted circadian rhythms in hypertension. [ABSTRACT FROM AUTHOR]

Background: Sex hormones and sex chromosomes play a vital role in cardiovascular disease. Testosterone plays a crucial role in men's health. Lower testosterone level is associated with cardiovascular and cardiometabolic diseases, including inflammation, atherosclerosis, and type 2 diabetes. Testosterone replacement is beneficial or neutral to men's cardiovascular health. Testosterone deficiency is associated with cardiovascular events. Testosterone supplementation to hypogonadal men improves libido, increases muscle strength, and enhances mood. We hypothesized that sex chromosomes (XX and XY) interaction with testosterone plays a role in arterial stiffening. Methods: We used four core genotype male mice to understand the inherent contribution of sex hormones and sex chromosome complement in arterial stiffening. Age-matched mice were either gonadal intact or castrated at eight weeks plus an additional eight weeks to clear endogenous sex hormones. This was followed by assessing blood pressure, pulse wave velocity, echocardiography, and ex vivo passive vascular mechanics. Results: Arterial stiffening but not blood pressure was more significant in castrated than testes-intact mice independent of sex chromosome complement. Castrated mice showed a leftward shift in stress–strain curves and carotid wall thinning. Sex chromosome complement (XX) in the absence of testosterone increased collagen deposition in the aorta and Kdm6a gene expression. Conclusion: Testosterone deprivation increases arterial stiffening and vascular wall remodeling. Castration increases Col1α1 in male mice with XX sex chromosome complement. Our study shows decreased aortic contractile genes in castrated mice with XX than XY sex chromosomes. Plain Language Summary: Cardiovascular disease is the leading cause of death worldwide. Cardiovascular disease presents differently in men and women. While men develop plaque buildup in large arteries, women develop buildup in the microvessels in the heart. Arterial stiffening, which is the hardening of arteries, increases with age in both men and women. Aging, coupled with the decline in sex hormones, exacerbates cardiovascular disease in women compared to men. Men with XY sex chromosomes have higher circulating testosterone, while women with XX sex chromosomes have increased circulating estradiol. The potential benefits of sex hormone replacement therapy are shown in men and women. Indeed, testosterone replacement deficiency is associated with adverse cardiovascular outcomes in men. Whether adverse events are dependent or independent of sex hormones' interaction with sex chromosomes is unknown. This study used the four core genotype mice comprising males with either XX or XY sex chromosome complement. We show castration increases arterial stiffening and collagen deposition on the arterial wall. We also identified the escapee and smooth muscle contractile genes that may play a role in arterial stiffening. Our data suggests that testosterone deprivation mediates arterial stiffening and remodeling. Highlights: Castration increases pulse wave velocity independent of blood pressure in male FCG mice. Castration-mediated carotid artery leftward shift in stress–strain. Arterial remodeling, including collagen deposition and decrease in contractile genes, was more significant in mice with XX sex chromosome complement. [ABSTRACT FROM AUTHOR]

Increased body weight (BW) induces inappropriate renin–angiotensin system (RAS) activation. The activation of the intrarenal RAS is associated with increased urinary angiotensinogen (uAGT), blood pressure (BP), and kidney damage. Here, we examined uAGT excretion levels in young non-diabetic human subjects with overweight (OW) and non-diabetic mice with high-fat diet (HFD)-induced OW. Human subjects (women and men; 20–28 years old) included two groups: (a) overweight (OW, n = 17, BMI ≥ 25); and (b) controls (normal weight (NW; n = 26, BMI ≤ 25). In these subjects, we measured BP, albuminuria, and protein levels of uAGT by ELISA adjusted by urinary creatinine (expressed by uAGT/uCrea). Mice (female and male C57BL/6J mice, 8 ± 2 weeks of age) also included two groups: HFD or normal fat diet (NFD) fed for 8 weeks. We measured BW, fasting blood glucose (FBG), BP by telemetry, albuminuria, and uAGT by ELISA. In humans: (i) no significant changes were observed in BP, albuminuria, and FBG when comparing NW and OW subjects; (ii) multivariate logistic regression analysis of independent predictors related to uAGT/uCrea levels demonstrated a strong association between uAGT and overweight; (iii) urinary reactive oxygen species (ROS) were augmented in men and women with OW; (iv) the uAGT/uCrea ratio was higher in men with OW. However, the uAGT/uCrea values were lower in women even with OW. In mice: (i) males fed an HFD for 8 weeks became OW while females did not; (ii) no changes were observed either in FBG, BP, or albuminuria; (iii) kidney ROS were augmented in OW male mice after 28 weeks but not in females; (iv) OW male mice showed augmented excretion of uAGT but this was undetectable in females fed either NFD or HFD. In humans and mice who are OW, the urinary excretion of AGT differs between males and females and overcomes overt albuminuria. [ABSTRACT FROM AUTHOR]

Plasma soluble prorenin receptor (sPRR) displays sexual dimorphism and is higher in women with type 2 diabetes mellitus (T2DM). However, the contribution of plasma sPRR to the development of vascular complications in T2DM remains unclear. We investigated if plasma sPRR contributes to sex differences in the activation of the systemic renin-angiotensin-aldosterone system (RAAS) and vascular damage in a model of high-fat diet (HFD)-induced T2DM. Male and female C57BL/6J mice were fed either a normal fat diet (NFD) or an HFD for 28 wk to assess changes in blood pressure, cardiometabolic phenotype, plasma prorenin/renin, sPRR, and ANG II. After completing dietary protocols, tissues were collected from males to assess vascular reactivity and aortic reactive oxygen species (ROS). A cohort of male mice was used to determine the direct contribution of increased systemic sPRR by infusion. To investigate the role of ovarian hormones, ovariectomy (OVX) was performed at 32 wk in females fed either an NFD or HFD. Significant sex differences were found after 28 wk of HFD, where only males developed T2DM and increased plasma prorenin/renin, sPRR, and ANG II. T2DM in males was accompanied by nondipping hypertension, carotid artery stiffening, and aortic ROS. sPRR infusion in males induced vascular thickening instead of material stiffening caused by HFD-induced T2DM. While intact females were less prone to T2DM, OVX increased plasma prorenin/renin, sPRR, and systolic blood pressure. These data suggest that sPRR is a novel indicator of systemic RAAS activation and reflects the onset of vascular complications during T2DM regulated by sex. NEW & NOTEWORTHY High-fat diet (HFD) for 28 wk leads to type 2 diabetes mellitus (T2DM) phenotype, concomitant with increased plasma soluble prorenin receptor (sPRR), nondipping blood pressure, and vascular stiffness in male mice. HFD-fed female mice exhibiting a preserved cardiometabolic phenotype until ovariectomy revealed increased plasma sPRR and blood pressure. Plasma sPRR may indicate the status of systemic renin-angiotensin-aldosterone system (RAAS) activation and the onset of vascular complications during T2DM in a sex-dependent manner. [ABSTRACT FROM AUTHOR]

Intermittent hypoxia (IH) is a feature of obstructive sleep apnea (OSA), a condition highly associated with hypertension‐related cardiovascular diseases. Repeated episodes of IH contribute to imbalance of angiogenic growth factors in the hypertrophic heart, which is key in the progression of cardiovascular complications. In particular, the interaction between vascular endothelial growth factor (VEGF) and the kallikrein‐kinin system (KKS) is essential for promoting angiogenesis. However, researchers have yet to investigate experimental models of IH that reproduce OSA, myocardial angiogenesis, and expression of KKS components. We examined temporal changes in cardiac angiogenesis in a mouse IH model. Adult male C57BI/6 J mice were implanted with Matrigel plugs and subjected to IH for 1–5 weeks with subsequent weekly histological evaluation of vascularization. Expression of VEGF and KKS components was also evaluated. After 3 weeks, in vivo myocardial angiogenesis and capillary density were decreased, accompanied by a late increase of VEGF and its type 2 receptor. Furthermore, IH increased left ventricular myocardium expression of the B2 bradykinin receptor, while reducing mRNA levels of B1 receptor. These results suggest that in IH, an unexpected response of the VEGF and KKS systems could explain the reduced capillary density and impaired angiogenesis in the hypoxic heart, with potential implications in hypertrophic heart malfunction. [ABSTRACT FROM AUTHOR]

Background: The soluble prorenin receptor (sPRR), a member of the renin-angiotensin system (RAS), is elevated in plasma of patients with preeclampsia, hypertension, chronic kidney disease (CKD), and type 2 diabetes. Our goal was to examine the relationship between sPRR and RAS activation to define whether sexual dimorphisms in sPRR might explain sex disparities in renal outcomes in patients with type 2 diabetes. Methods: Two hundred sixty-nine participants were included in the study (mean age, 48 ± 16 years; 42% men, 58% women), including 173 controls and 96 subjects with type 2 diabetes. In plasma and urine, we measured sPRR, plasma renin activity (PRA), and prorenin. In the urine, we also measured angiotensinogen along with other biomarkers of renal dysfunction. Results: Plasma sPRR and PRA were significantly higher in women with type 2 diabetes compared to men. In these women, plasma sPRR was positively correlated with PRA, age, and body mass index (BMI). In contrast, in men the sPRR in urine but not in plasma positively correlated with eGFR in urine, but negatively correlated with urine renin activity, plasma glucose, age, and BMI. Conclusions: In patients with type 2 diabetes, sPRR contributes to RAS stimulation in a sex-dependent fashion. In diabetic women, increased plasma sPRR parallels the activation of systemic RAS; while in diabetic men, decreased sPRR in urine matches intrarenal RAS stimulation. sPRR might be a potential indicator of intrarenal RAS activation and renal dysfunction in men and women with type 2 diabetes. [ABSTRACT FROM AUTHOR]

Corneal avascularization is essential for normal vision. Several antiangiogenic factors were identified in cornea such as endostatin and angiostatin. Cathepsin V, which is highly expressed in the cornea, can hydrolyze human plasminogen to release angiostatin fragments. Herein, we describe a detailed investigation of the expression profile of cathepsins B, L, S and V in the human cornea and the role of cysteine peptidases in modulating angiogenesis both in vitro and in vivo . We used various methodological tools for this purpose, including real-time PCR, SDS-PAGE, western blotting, catalytic activity assays, cellular assays and induction of corneal neovascularity in rabbit eyes. Human corneal enzymatic activity assays revealed the presence of cysteine proteases that were capable of processing endogenous corneal plasminogen to produce angiostatin-like fragments. Comparative real-time analysis of cathepsin B, L, S and V expression revealed that cathepsin V was the most highly expressed, followed by cathepsins L, B and S. However, cathepsin V depletion revealed that this enzyme is not the major cysteine protease responsible for plasminogen degradation under non-pathological conditions. Furthermore, western blotting analysis indicated that only cathepsins B and S were present in their enzymatically active forms. In vivo analysis of angiogenesis demonstrated that treatment with the cysteine peptidase inhibitor E64 caused a reduction in neovascularization. Taken together, our results show that human corneal cysteine proteases are critically involved in angiogenesis. [ABSTRACT FROM AUTHOR]

Objective Thimet oligopeptidase ( TOP) is a metalloprotease that has been associated with peptide processing in several nervous system structures, and its substrates include several peptides such as bradykinin, amyloid beta (Aβ), and major histocompatibility complex ( MHC) class I molecules. As shown previously by our research group, patients with temporal lobe epilepsy (TLE) have a high level of kinin receptors as well as kallikrein, a kinin-releasing enzyme, in the hippocampus. Methods In this study, we evaluated the expression, distribution, and activity of TOP in the hippocampus of patients with TLE and autopsy-control tissues, through reverse-transcription polymerase chain reaction ( RT- PCR), enzymatic activity, Western blot, and immunohistochemistry. In addition, hippocampi of rats were analyzed using the pilocarpine-induced epilepsy model. Animals were grouped according to the epilepsy phases defined in the model as acute, silent, and chronic. Results Increased TOP mRNA expression, decreased protein levels and enzymatic activity were observed in tissues of patients, compared to control samples. In addition, decreased TOP distribution was also visualized by immunohistochemistry. Similar results were observed in tissues of rats during the acute phase of epilepsy model. However, increased TOP mRNA expression and no changes in immunoreactivity were found in the silent phase, whereas increased TOP mRNA expression and increased enzymatic activity were observed in the chronic phase. Significance The results show that these alterations could be related to a failure in the mechanisms involved in clearance of inflammatory peptides in the hippocampus, suggesting an accumulation of potentially harmful substances in nervous tissue such as Aβ, bradykinin, and antigenic peptides. These accumulations could be related to hippocampal inflammation observed in TLE subjects. [ABSTRACT FROM AUTHOR]

Abstract: Many studies indicate that thimet oligopeptidase (EC3.4.24.15; TOP) can be implicated in the metabolism of bioactive peptides, including dynorphin 1–8, α-neoendorphin, β-neoendorphin and GnRH. Furthermore, the higher levels of this peptidase are found in neuroendocrine tissue and testis. In the present study, we have evaluated the effect of acute cocaine administration in male rats on TOP specific activity and mRNA levels in prosencephalic brain areas related with the reward circuitry; ventral striatum, hippocampus, and frontal cortex. No significant differences on TOP specific activity were detected in the hippocampus and frontal cortex of cocaine treated animals compared to control vehicle group. However, a significant increase in activity was observed in the ventral striatum of cocaine treated-rats. The increase occurred in both, TOP specific activity and TOP relative mRNA amount determined by real time RT-PCR. As TOP can be implicated in the processing of many neuropeptides, and previous studies have shown that cocaine also alters the gene expression of proenkephalin and prodynorphin in the striatum, the present findings suggest that TOP changes in the brain could play important role in the balance of neuropeptide level correlated with cocaine effects. [Copyright &y& Elsevier]

Abstract: Some central effects of cocaine administration seem to be related to angiotensin II (Ang II) or its metabolites. Nonetheless, it is still an open question whether or not the levels of angiotensin I-converting enzyme (ACE), the main Ang II generating enzyme, are modified by cocaine administration. To evaluate the effect of acute and subchronic cocaine administration on ACE activity and mRNA expression, male rats were randomly assigned to saline or cocaine group. Acute and subchronic cocaine administration induced a significant increase in ACE activity and mRNA expression in the frontal cortex and striatum but not in the hippocampus. These results suggest that some of the Ang II related effects of cocaine upon the central nervous system can be mediated by changes on the expression and activity of ACE in the striatum and frontal cortex. [Copyright &y& Elsevier]

Proteases are essential either for the release of neuropeptides from active or inactive proteins or for their inactivation. Neuropeptides have a fundamental role in sleep-wake cycle regulation and their actions are also likely to be regulated by proteolytic processing. Using fluorescence resonance energy transfer substrates, specific protease inhibitors and real-time PCR we demonstrate changes in angiotensin I-converting enzyme (ACE) expression and proteolytic activity in the central nervous system in an animal model of paradoxical sleep deprivation during 96 h (PSD). Male rats were distributed into five groups (PSD, 24 h, 48 h and 96 h of sleep recovery after PSD and control). ACE activity and mRNA levels were measured in hypothalamus, hippocampus, brainstem, cerebral cortex and striatum tissue extracts. In the hypothalamus, the significant decrease in activity and mRNA levels, after PSD, was only totally reversed after 96 h of sleep recovery. In the brainstem and hippocampus, although significant, changes in mRNA do not parallel changes in ACE specific activity. Changes in ACE activity could affect angiotensin II generation, angiotensin 1-7, bradykinin and opioid peptides metabolism. ACE expression and activity modifications are likely related to some of the physiological changes (cardiovascular, stress, cognition, metabolism function, water and energy balance) observed during and after sleep deprivation. [ABSTRACT FROM AUTHOR]

Aging is a nonmodifiable risk factor for cardiovascular disease associated with arterial stiffening and endothelial dysfunction. We hypothesized that sex differences exist in vascular aging processes and would be attenuated by global deletion of the G protein-coupled estrogen receptor. Blood pressure was measured by tail-cuff plethysmography, pulse wave velocity (PWV) and echocardiography were assessed with high-resolution ultrasound, and small vessel reactivity was measured using wire myography in adult (25 wk) and middle-aged (57 wk) male and female mice. Adult female mice displayed lower blood pressure and PWV, but this sex difference was absent in middle-aged mice. Aging significantly increased PWV but not blood pressure in both sexes. Adult female carotids were more distensible than males, but this sex difference was lost during aging. Acetylcholine-induced relaxation was greater in female than male mice at both ages, and only males showed aging-induced changes in cardiac hypertrophy and function. GPER deletion removed the sex difference in PWV and ex vivo stiffness in adult mice. The sex difference in blood pressure was absent in KO mice and was associated with endothelial dysfunction in females. These findings indicate that the impact of aging on arterial stiffening and endothelial function is not the same in male and female mice. Moreover, nongenomic estrogen signaling through GPER impacted vascular phenotype differently in male and female mice. Delineating sex differences in vascular changes during healthy aging is an important first step in improving early detection and sex-specific treatments in our aging population. [ABSTRACT FROM AUTHOR]

Higher reproductive age is associated with an increased risk of gestational diabetes, pre-eclampsia, and severe vaginal tearing during delivery. Further, menopause is associated with vaginal stiffening. However, the mechanical properties of the vagina during reproductive aging before the onset of menopause are unknown. Therefore, the first objective of this study was to quantify the biaxial mechanical properties of the nulliparous murine vagina with reproductive aging. Menopause is further associated with a decrease in elastic fiber content, which may contribute to vaginal stiffening. Hence, our second objective was to determine the effect of elastic fiber disruption on the biaxial vaginal mechanical properties. To accomplish this, vaginal samples from CD-1 mice aged 2–14 months underwent extension-inflation testing protocols (n = 64 total; n = 16/age group). Then, half of the samples were randomly allocated to undergo elastic fiber fragmentation via elastase digestion (n = 32 total; 8/age group) to evaluate the role of elastic fibers. The material stiffness increased with reproductive age in both the circumferential and axial directions within the control and elastase-treated vaginas. The vagina demonstrated anisotropic mechanical behavior, and anisotropy increased with age. In summary, vaginal remodeling with reproductive age included increased direction-dependent material stiffness, which further increased following elastic fiber disruption. Further work is needed to quantify vaginal remodeling during pregnancy and postpartum with reproductive aging to better understand how age-related vaginal remodeling may contribute to an increased risk of vaginal tearing. [ABSTRACT FROM AUTHOR]

The intrarenal renin-angiotensin system is critical for the regulation of tubule sodium reabsorption, renal haemodynamics and blood pressure. The excretion of renin in urine can result from its increased filtration, the inhibition of renin reabsorption by megalin in the proximal tubule, or its secretion by the principal cells of the collecting duct. Modest increases in circulating or intrarenal angiotensin II (ANGII) stimulate the synthesis and secretion of angiotensinogen in the proximal tubule, which provides sufficient substrate for collecting duct-derived renin to form angiotensin I (ANGI). In models of ANGII-dependent hypertension, ANGII suppresses plasma renin, suggesting that urinary renin is not likely to be the result of increased filtered load. In the collecting duct, ANGII stimulates the synthesis and secretion of prorenin and renin through the activation of ANGII type 1 receptor (AT1R) expressed primarily by principal cells. The stimulation of collecting duct-derived renin is enhanced by paracrine factors including vasopressin, prostaglandin E2 and bradykinin. Furthermore, binding of prorenin and renin to the prorenin receptor in the collecting duct evokes a number of responses, including the non-proteolytic enzymatic activation of prorenin to produce ANGI from proximal tubule-derived angiotensinogen, which is then converted into ANGII by luminal angiotensin-converting enzyme; stimulation of the epithelial sodium channel (ENaC) in principal cells; and activation of intracellular pathways linked to the upregulation of cyclooxygenase 2 and profibrotic genes. These findings suggest that dysregulation of the renin-angiotensin system in the collecting duct contributes to the development of hypertension by enhancing sodium reabsorption and the progression of kidney injury. [ABSTRACT FROM AUTHOR]

Background: Androgens are important sex hormones in both men and women and are supplemented when endogenous levels are low, for gender transitioning, or to increase libido. Androgens also circulate at higher levels in women with polycystic ovarian syndrome, a condition that increases the risk for cardiovascular diseases including hypertension and arterial stiffness. Since our previous work shows an important role for the G protein-coupled estrogen receptor (GPER) in arterial stiffness, we hypothesized that other hormones including androgens may impact arterial stiffness in female mice via downregulation of GPER. Methods: The impact of the non-aromatizable androgen dihydrotestosterone (DHT), the glucocorticoid dexamethasone, and the progestin medroxyprogesterone acetate (all 100 nM for 24 h) on GPER and ERα expression was assessed in cultured vascular smooth muscle cells using droplet digital PCR (ddPCR). To assess the in vivo impact of the DHT-induced downregulation of GPER, female ovary-intact C57Bl/6 mice at 15–16 weeks of age were treated with silastic capsules containing DHT for 4 weeks, one with a dosage expected to mimic human male DHT levels and another to double the expected human concentration (n = 8–9/group). Results: In cultured vascular smooth muscle cells, GPER mRNA was decreased by DHT (P = 0.001) but was not impacted by dexamethasone or medroxyprogesterone. In contrast, ERα expression in cultured cells was significantly suppressed by all three hormones (P < 0.0001). In control mice or mice treated with a single or double dose of DHT, a dose-dependent increase in body weight was observed (control 22 ± 2 g, single dose 24 ± 2 g, double dose 26 ± 2 g; P = 0.0002). Intracarotid stiffness measured via pulse wave velocity showed a more than two-fold increase in both DHT-treated groups (control 1.9 ± 0.3 m/s, single dose 4.3 ± 0.8 m/s, double dose 4.8 ± 1.0 m/s). This increase in arterial stiffness occurred independent of changes in blood pressure (P = 0.59). Histological analysis of aortic sections using Masson's trichrome showed a significant decrease in collagen between the control group (24 ± 5%) and the double dose group (17 ± 3%, P = 0.007), despite no changes in aortic wall thickness or smooth muscle content. Lastly, ddPCR showed that in vivo DHT treatment decreased aortic expression of both GPER (control 20 ± 5, single dose 10.5 ± 5.6, double dose 10 ± 4 copies/ng; P = 0.001) and ERα (control 54 ± 2, single dose 24 ± 13, and double dose 23 ± 12 copies/ng; P = 0.003). Conclusions: These findings indicate that androgen promotes arterial stiffening and cardiovascular damage in female mice and is associated with decreased estrogen receptor expression. These data are important for transgender men, women using testosterone for fitness or reduced libido, as well as patients with polycystic ovarian syndrome. Plain language summary: The current study investigated the impact of other hormones on estrogen receptor expression and its impact on vascular health. In both cultured vascular cells and in vivo vascular tissue, dihydrotestosterone decreased the expression of estrogen receptors. Female mice treated with dihydrotestosterone also displayed increased body weight and arterial stiffness despite no change in blood pressure. These findings indicate that increases in testosterone may impact vascular health, which may be important clinically for transgender men, women using testosterone for fitness or reduced libido, as well as patients with polycystic ovarian syndrome. Highlights: Treatment of cultured vascular smooth muscle cells with other hormones, including dihydrotestoterone, significantly decreased the expression of estrogen receptors. In vivo treatment of female mice with dihydrotestosterone also reduced vascular estrogen receptor expression and was associated with increased arterial stiffness but not blood pressure. These results highlight the need to consider the hormonal milieu in when considering the impact of hormonal changes on vascular health. [ABSTRACT FROM AUTHOR]

Obesity is assumed to be a major cause of human essential hypertension; however, the mechanisms responsible for weight-related increase in blood pressure (BP) are not fully understood. The prevalence of hypertension induced by obesity has grown over the years, and the role of the renin-angiotensin-aldosterone system (RAAS) in this process continues to be elucidated. In this scenario, the ob/ob mice are a genetic obesity model generally used for metabolic disorder studies. These mice are normotensive even though they present several metabolic conditions that predispose them to hypertension. Although the normotensive trait in these mice is associated with the poor activation of sympathetic nervous system by the lack of leptin, we demonstrated that ob/ob mice present massively increased aminopeptidase A (APA) activity in the circulation. APA enzyme metabolizes angiotensin (ANG) II into ANG III, a peptide associated with intrarenal angiotensin type 2 (AT2) receptor activation and induction of natriuresis. In these mice, we found increased ANG-III levels in the circulation, high AT2 receptor expression in the kidney, and enhanced natriuresis. AT2 receptor blocking and APA inhibition increased BP, suggesting the ANG III-AT2 receptor axis as a complementary BP control mechanism. Circulating APA activity was significantly reduced by weight loss independently of leptin, indicating the role of fat tissue in APA production. Therefore, in this study we provide new data supporting the role of APA in BP control in ob/ob mouse strain. These findings improve our comprehension about obesity-related hypertension and suggest new tools for its treatment. [ABSTRACT FROM AUTHOR]

Background Proteolitics enzymes are essential in the release and metabolism of neuropeptides. The neuropeptides are related in the regulation of the functions of the central nervous system (SNC), in particular in the regulation of the states of vigil and sleep. Currently, few studies on the expression and activity of proteolitics enzymes, EC 24,11, EC 24, 15 and EC 24. 16, they possess important paper in conditions of sleep deprivation. Materials and methods We establish methods of enzymatic determination in brain of rats (group privation sleep and control). The hydrolysis of fluorescence substrate was detected in espectofluorimetre adjusted for emission 320nm and excitement 420nm. The plate was kept in compartment (37. C). The increase of fluorescence due the hydrolysis was registered and the values corrected for UAF/min/mg of protein. The sequences of hydrolysis was analyzed in system HPLC. Results Important alterations in the expression and activity of enzymes EC 24,11, EC 24,15 and EC 24. 16. The alterations are specific of functional structures of the SNC having increase or reduction in different regions (hippocampus and striatum). Conclusions From these evidences we will go to determine level of genetic expression and which alterations can be taken to the increase of the proteolitic activity. Using the methodology reaction in chain of polimerase in real time. [ABSTRACT FROM AUTHOR]

Changes in the maternal environment can induce fetal adaptations that result in the progression of chronic diseases in the offspring. The objective of the present study was to evaluate the effects of maternal chronic sleep restriction on blood pressure, renal function and cardiac baroreflex response on male offspring at adult age. Female 3-month-old Wistar rats were divided in two experimental groups: control (C) and chronic sleep restricted (CSR). Pregnancy was confirmed by vaginal smear. Chronic sleep restricted females were subjected to sleep restriction by the multiple platform technique for 20 h daily, between the 1st and 20th day of pregnancy. After birth, the litters were reduced to 6 rats per mother, and were designated as offspring from control (OC) and offspring from chronic sleep restricted (OCSR). Indirect blood pressure (BPi – tail cuff) was measured by plethysmography in male offspring at 3 months old. Following, the renal function and cardiac baroreflex response were analyzed. Values of BPi in OCSR were significantly higher compared to OC [OC: 127±2.6 (19); OCSR: 144±2.5 (17) mmHg]. The baroreflex sensitivity to the increase of blood pressure was reduced in OCSR [Slope: OC: −2.6±0.15 (9); OCRS: −1.6±0.13 (9)]. Hypothalamic activity of ACE2 was significantly reduced in OCSR compared to OC [OC: 97.4±15 (18); OSR: 60.2±3.6 (16) UAF/min/protein mg]. Renal function alteration was noticed by the increase in glomerular filtration rate (GFR) observed in OCSR [OC: 6.4±0.2 (10); OCSR: 7.4±0.3 (7)]. Chronic sleep restriction during pregnancy caused in the offspring hypertension, altered cardiac baroreflex response, reduced ACE-2 activity in the hypothalamus and renal alterations. Our data suggest that the reduction of sleeping time along the pregnancy is able to modify maternal homeostasis leading to functional alterations in offspring. [ABSTRACT FROM AUTHOR]

R6256 --> 849.39 --> Aging is a nonmodifiable risk factor for cardiovascular disease associated with arterial stiffening and cardiac dysfunction. We previously showed an important role for G protein‐coupled estrogen receptor (GPER) in modulating female protection from arterial stiffening. In this study, we hypothesized that aging would decrease vascular compliance in GPER knockout (ko) mice to a greater extent than wildtype (wt) mice. Adult (25 weeks) and middle‐aged (57 weeks) mice were subjected to high frequency ultrasound for pulse wave velocity (PWV), and structural remodeling in the carotid artery was assessed with biaxial pressure myography followed by constitutive modeling. Data was analyzed by 3‐way ANOVA and Sidak's post hoc tests. As we previously showed, PWV was significantly lower in adult female wt mice versus their male counterparts (1.4 ± 0.05 vs. 1.1 ± 0.02 m/s; P=0.0004) but was not different in adult ko mice (1.6 ± 0.07 vs 1.4 ± 0.08, P=0.20). Interestingly, PWV increased with aging in female but not male wt mice, so that the sex difference was lost (1.7 ± 0.03 vs 1.7 ± 0.06, P=0.99). Despite the lower PWV, circumferential linearized material stiffness in passive conditions was elevated in adult female wt versus male wt (1.9 ± 0.2 vs. 1.4 ± 0.2 MPa; P=0.02), but this sex difference was lost in middle‐aged wt mice (1.3 ± 0.1 vs. 1.2 ± 0.1 MPa; P=0.87). Aging significantly increased the ratio of thick to thin collagen only in male wt and female ko groups. We found that females but not males experience an increase in PWV at middle‐age along with a decrease in circumferential stiffness. In contrast, female GPER mice already display a higher PWV as adults, indicating that GPER deletion in females is a model of accelerated vascular aging. [ABSTRACT FROM AUTHOR]

Aim Of the Study: During type 2 diabetes (T2D) and hypertension there is stimulation of renal proximal tubule angiotensinogen (AGT), but whether urinary excretion of AGT (uAGT) is an indicator of glomerular damage or intrarenal RAS activation is unclear. We tested the hypothesis that elevations in uAGT can be detected in the absence of albuminuria in a mouse model of T2D.Methods: Male C57BL/6 mice (N = 10) were fed a high fat (HFD; 45% Kcal from fat) for 28 weeks, and the metabolic phenotype including body weight, blood pressures, glucose, insulin, ippGTT, HOMA-IR, and cholesterol was examined. In addition, kidney Ang II content and reactive oxygen species (ROS) was measured along with urinary albumin, creatinine, Ang II, and AGT.Results: All parameters consistent with T2D were present in mice after 12-14 weeks on the HFD. Systolic BP increased after 18 weeks in HFD but not NFD mice. Intrarenal ROS and Ang II concentrations were also increased in HFD mice. Remarkably, these changes paralleled the augmentation uAGT excretion (3.66 ± 0.50 vs. 0.92 ± 0.13 ng/mg by week 29; P < 0.01), which occurred in the absence of overt albuminuria.Conclusions: In HFD-induced T2D mice, increases in uAGT occur in the absence of overt renal injury, indicating that this biomarker accurately detects early intrarenal RAS activation. [ABSTRACT FROM AUTHOR]

Thimet oligopeptidase (THOP1) is thought to be involved in neuropeptide metabolism, antigen presentation, neurodegeneration, and cancer. Herein, the generation of THOP1 C57BL/6 knockout mice (THOP1−/−) is described showing that they are viable, have estrus cycle, fertility, and a number of puppies per litter similar to C57BL/6 wild type mice (WT). In specific brain regions, THOP1-/- exhibit altered mRNA expression of proteasome beta5, serotonin 5HT2a receptor and dopamine D2 receptor, but not of neurolysin (NLN). Peptidomic analysis identifies differences in intracellular peptide ratios between THOP1-/- and WT mice, which may affect normal cellular functioning. In an experimental model of multiple sclerosis THOP1-/- mice present worse clinical behavior scores compared to WT mice, corroborating its possible involvement in neurodegenerative diseases. THOP1-/- mice also exhibit better survival and improved behavior in a sepsis model, but also a greater peripheral pain sensitivity measured in the hot plate test after bradykinin administration in the paw. THOP1-/- mice show depressive-like behavior, as well as attention and memory retention deficits. Altogether, these results reveal a role of THOP1 on specific behaviors, immune-stimulated neurodegeneration, and infection-induced inflammation. [ABSTRACT FROM AUTHOR]