Control Spontaneously Hypertensive Rats Research Articles

Changes in the Urinary Metabolites in Losartan-Treated Spontaneously Hypertensive Rats

Introduction: This study examined the association of losartan induced changes in urinary metabolomic profile with the changes in blood pressure (BP) and renin-angiotensin- aldosterone system (RAAS) in spontaneously hypertensive rats (SHR). Methods: Male SHR were administered with either 0.5 mL of distilled water (control group, n=6) or 10 mg.kg -1 of losartan (group 2, n=6) daily by oral gavage for 4 weeks. Body weight, BP, food and water intake were measured weekly. At week 4, urine was collected for urinary electrolyte analysis and metabolite profiling, after which the animals were euthanised by decapitation and blood was collected for analysis of components of RAAS and electrolyte concentrations. Urine metabolite profile of SHR was determined using proton nuclear magnetic resonance ( 1 H-NMR) spectrometry combined with multivariate data analysis. Results: At week 4, losartan- treated SHR had significantly lower BP than non-treated SHR. There were no differences in water and food intake, body weight, serum and urinary electrolyte concentrations or in their urinary excretions between the two groups. No differences were evident in the components of RAAS except that the angiotensinogen level was significantly higher in losartan-treated SHR compared to non-treated SHR. Orthogonal partial least squares discriminant analysis (OPLS-DA) showed clear separation of urinary metabolites between control and losartan-treated SHR. Losartan-treated SHR group was separated from the control group by changes in the intermediates involved in glycine, serine and threonine metabolism. Conclusion: Antihypertensive effect of losartan in SHR seems to be associated with changes in urinary metabolite profile, particularly involving the metabolism of glycine, serine and threonine.

Comparative Assessment of the Activity of Racemic and Dextrorotatory Forms of Thioctic (Alpha-Lipoic) Acid in Low Back Pain: Preclinical Results and Clinical Evidences From an Open Randomized Trial.

Peripheral neuropathies, characterized by altered nociceptive and muscular functions, are related to oxidative stress. Thioctic acid is a natural antioxidant existing as two optical isomers, but most clinically used as racemic mixture. The present study investigated the central nervous system’s changes which followed loose-ligation-derived compression of sciatic nerve, the putative neuroprotective role of thioctic acid and the pain-alleviating effect on low-back pain suffering patients. Loose ligation of the right sciatic nerve was performed in spontaneously hypertensive rats (SHR), a model of increased oxidative stress, and in normotensive Wistar-Kyoto rats (WKY). Animals with sciatic nerve ligation were left untreated or were treated intraperitoneally for 15 days with 250 μmol·kg−1·die−1 of (+/−)-thioctic acid; 125 μmol·kg−1·die−1 of (+/−)-thioctic acid; 125 μmol·kg−1·die−1 of (+)-thioctic acid lysine salt; 125 μmol·kg−1·die−1 of (−)-thioctic acid; 300 μmol·kg−1·die−1 pregabalin. Control SHR and WKY rats received the same amounts of vehicle. The clinical trial NESTIORADE (Sensory-Motor Neuropathies of the Sciatic Nerve: Comparative evaluation of the effect of racemic and dextro-rotatory forms of thioctic acid) examined 100 patients (49 males and 51 females aged 53 ± 11 years) dividing them into two equal-numbered groups, each treated daily for 60 days with 600 mg of (+/−)-thioctic acid or (+)-thioctic acid, respectively. The trial was registered prior to patient enrollment at EudraCT website (OSSC Number: 2011-000964-81). In the preclinical study, (+)-thioctic acid was more active than (+/−)- or (−)-enantiomers in relieving pain and protecting peripheral nerve as well as in reducing oxidative stress and astrogliosis in the spinal cord. Main findings of NESTIORADE clinical trial showed a greater influence on painful symptomatology, a quicker recovery and a better impact on quality of life of (+)-thioctic acid vs. (+/−)-thioctic acid. These data may have a pharmacological and pharmacoeconomical relevance and suggest that thioctic acid, above all (+)-enantiomer, could be considered for treatment of low-back pain involving neuropathy.

Angiotensin-Converting Enzyme Inhibitor, Captopril, Improves Scar Healing in Hypertensive Rats.

Pathological cutaneous scars, with aberrant extracellular matrix accumulation, have multiple origins. Antihypertensive medications, such as calcium channel blockers, have been used to treat pathological scars. However, a relationship between angiotensin-converting enzyme (ACE) inhibitors, pathological scars, and blood pressure (BP) has never been reported. Here, we aimed to compare the differences in scar development and the effects of the administration of systemic ACE inhibitor on scar tissue in a normotensive rat, the Wistar Kyoto rat (WKY), a hypertensive rat, and the spontaneously hypertensive rat (SHR). Using an 8-mm punch, we created two full-thickness skin defects in a total of 32 rats (16 WKY and 16 SHR) to obtain a total of 64 wounds. We established control WKY (n = 16), captopril-treated WKY (n = 16), control SHR (n = 16), and captopril-treated SHR (n = 16) groups and started captopril (100 mg/g per day) treatment on day 21 in the appropriate groups. The BP of all groups was measured at 0, 3, and 5 weeks. The scar area was measured by histopathological examination, and scarring was expressed in terms of scar area and fibroblast and capillary counts. The expression of heat shock protein (HSP) 47, type I and III collagens, alpha-smooth muscle actin (α-SMA), Ki67, and vascular endothelial growth factor (VEGF) was investigated using immunohistochemistry. The scar area and fibroblast count were significantly higher in control SHR than in control WKY. The scar area, fibroblast count, and capillary count were significantly smaller in captopril-treated SHR than in control SHR. Immunostaining for α-SMA, Ki67, and VEGF also showed a noticeable decrease in scarring in the treated SHR compared with that in control SHR. Thus, BP affects scar development in a rat model, and an ACE inhibitor is more effective at reducing scars in hypertensive rats than in normotensive rats.

Ischemic Conditioning Ameliorated Hypertension and Vascular Remodeling of Spontaneously Hypertensive Rat via Inflammatory Regulation.

Vascular remodeling is an initial step in the development of hypertension. Limb remote ischemic conditioning (LRIC) is a physiological treatment that induces endogenous protective effect during acute ischemic injury. However, the impact of long-term LRIC on hypertension, a chronic disease, is unknown. In this study, we aimed to investigate the LRIC effect on blood pressure and vascular remodeling in spontaneously hypertensive rat (SHR) model and patients with prehypertension and early-stage hypertension. LRIC of rats was performed once a day for 6-weeks. Blood pressure, vascular remodeling (cross-sectional area, extracellular deposition, and smooth muscle cell area), inflammation (inflammatory factors, and inflammatory cells) were compared among normotensive Wistar-Kyoto rats (WKY), WKY RIC group, SHR control group, and SHR RIC. Long-term LRCI treatment (twice a day for 4-weeks) was performed on patients with prehypertension or early-stage hypertension. Blood pressure and pulse wave velocity (PWV) were analyzed before and after LRIC treatment. LRIC treatment decreased blood pressure in SHR (n = 9-10). LRIC ameliorated vascular remodeling by decreasing cross-sectional area, suppressing deposition of the extracellular matrix, and hypertrophy of smooth muscle cell in conduit artery and small resistance artery (n = 7). LRIC decreased proinflammatory factors while increasing the anti-inflammatory factors in the circulation (n = 5). LRIC decreased circulating monocyte and natural killer T-cell levels (n = 5). Furthermore, LRIC treatment decreased blood pressure and improved vascular stiffness in patients (n = 20). In conclusion, long term LRIC could decrease blood pressure and ameliorate vascular remodeling via inflammation regulation. LRIC could be a preventive treatment for people with blood pressure elevation or prehypertension.

Histological changes in the hippocampus of both cerebral hemispheres of Wistar and SHR rats under experimental chronic cerebral hypoperfusion

Сhronic cerebral hypoperfusion (ChCH) and arterial hypertension are the factors of risk for сerebrovascular diseases, nevertheless the underlying pathophysiological mechanisms remain unclear.Aim. To investigate histological hippocampal changes in both cerebral hemispheres of Wistar and SHR rats under the chronic cerebral hypoperfusion conditions.Маterials and methods. The experiments were carried out on male Wistar and SHR rats (6 weeks old, weight 95–100 g), which underwent occlusion of left common carotid artery to model ChCH. All manipulations were carried out in anesthetized with ketamine (60 mg/kg, i.p.) animals. In 8 weeks, the features of the hippocampal structure damage wer studied.Results. An interhemispheric difference in the level of hippocampal cells with the signs of nuclear fragmentation in the control Wistar and SHR rats with more pronounced indices in the latter on the left was shown. ChCH modeling caused hippocampal damage in both cerebral hemispheres. Under these conditions, the number of damaged hippocampal cells was higher in SHR than in Wistar rats on the left by 34.7 % (P < 0.05), and in the right hippocampus of both lines’ rats the increase in such cells was almost the same.Conclusion. Taken together, these data showed that an increase in the number of neurons with the signs of nuclear fragmentation under ChCH was observed in both rat lines, and the severity of changes was greater in SHR animals, which indicates an increased risk of structural brain damage in the presence of hypertension.

Downregulation of the Glo1 Gene Is Associated with Reduced Adiposity and Ectopic Fat Accumulation in Spontaneously Hypertensive Rats.

Methylglyoxal (MG), a potent precursor of advanced glycation end-products (AGE), is increased in metabolic disorders such as diabetes and obesity. MG and other dicarbonyl metabolites are detoxified by the glyoxalase system in which glyoxalase 1, coded by the Glo1 gene, serves as the rate-limiting enzyme. In this study, we analyzed the effects of Glo1 downregulation on glucose and lipid metabolism parameters in spontaneously hypertensive rats (SHR) by targeting the Glo1 gene (SHR-Glo1+/− heterozygotes). Compared to SHR wild-type animals, SHR-Glo1+/− rats showed significantly reduced Glo1 expression and lower GLO1 activity in tissues associated with increased MG levels. In contrast to SHR controls, SHR-Glo1+/− rats exhibited lower relative weight of epididymal fat, reduced ectopic fat accumulation in the liver and heart, and decreased serum triglycerides. In addition, compared to controls, SHR-Glo1+/− rats showed reduced serum insulin and increased basal and insulin stimulated incorporation of glucose into white adipose tissue lipids (lipogenesis). Reduced ectopic fat accumulation in the heart was associated with significantly increased pAMPK/AMPK ratio and GLUT4 activity. These results provide evidence that Glo1 downregulation in SHR is associated with reduced adiposity and ectopic fat accumulation, most likely mediated by AMPK activation in the heart.

Abstract 15555: Potential Cure for Hypertension? The Effect of Crispr Genome Editing

Hypertension is recognized as one of the largest contributors to the global burden of disease. Unfortunately, for the majority of patients, hypertension is poorly controlled due, in part, to poor medical compliance resulting from the need to take one or more drugs, often several times daily. An ideal therapy would be administered a single time but yield long-term blood pressure control. Under the appropriate condition, we hypothesize that this modality could potentially lead to a cure for hypertension. In this study, we investigated whether that sustained, and possibly life-long, reductions in blood pressure could be achieved via Crispr-Cas9 mediated disruption of a key gene in the RAAS, Angiotensinogen (AGT). In vitro, we demonstrated that expression of Crispr-Cas9 system in the BRL 3A rat liver cell line led to a significant reduction in AGT protein levels (75% reduction, N=3, P&lt;0.01). Delivery of the Crispr-Cas9 system into the liver via systemic delivery of the hepatocyte-targeting AAV8 reduced both AGT mRNA (70% reduction, N=5, P&lt;0.01) and circulating AGT protein (50% reduction, N=5, P&lt;0.01) and Ang II levels (33% reduction, n=5, P&lt;0.01). In the SHR model of hypertension, Crispr-Cas9 mediated loss of AGT expression reduced systolic blood pressure in adult animals with established hypertension (30-35mmHg decrease in both females and males, N=12, P&lt;0.001). Importantly, AGT gene disruption also prevented the spontaneous development of hypertension in young pre-hypertensive SHR (SHR control: 55-60mmHg increase in systolic blood pressure both female and male SHR; SHR plus Crispr-Cas9: 30-33 mmHg increase. N=12. P&lt;0.001). Importantly, in all the models studied, reductions in blood pressure were sustained for at least 4 months. Importantly, the partial disruption of the hepatic AGT gene was sufficient to control hypertension but did not block the renin-angiotensin response to cardiovascular stress such as sodium depletion. In summary, we have demonstrated that targeting the Crispr-Cas9 system to RAAS reduces blood pressure and may be a potential therapy to achieve safe and sustained, possibly life-long, control of hypertension and this approach maybe a cure for hypertension.

Proteomic identification of the proteins related to cigarette smoke-induced cardiac hypertrophy in spontaneously hypertensive rats

Smoking increases the risk of cardiovascular diseases. The present study was designed to determine the effects of 2-month exposure to cigarette smoke (CS) on proteins in the left ventricles of spontaneously hypertensive rats (SHR) and to identify the molecular targets associated with the pathogenesis/progression of CS-induced cardiac hypertrophy. SHR and Wistar Kyoto rats (WKY) were exposed to CS at low (2 puffs/min for 40 min) or high dose (2 puffs/min for 120 min), 5 days a week for 2 months. Using the two-dimensional fluorescence difference gel electrophoresis combined with MALDI-TOF/TOF tandem mass spectrometry, we compared differences in the expression levels of proteins in the whole left ventricles induced by long-term smoking. High-dose CS mainly caused cardiac hypertrophy in SHR, but not WKY, but no change in blood pressure. Proteomic analysis identified 30 protein spots with significant alterations, with 14 up-regulated and 16 down-regulated proteins in the left ventricles of CS-exposed SHR, compared with control SHR. Among these proteins, two members of the heat shock proteins (HSP70 and HSP20) showed significant up-regulation in the left ventricles of CS high-dose SHR, and the results were confirmed by western blot analysis. Our findings suggested that HSPs play an important role in regulation of CS-induced cardiac hypertrophy.

Protective Effect of Vitis labrusca Leaves Extract on Cardiovascular Dysfunction through HMGB1-TLR4-NFκB Signaling in Spontaneously Hypertensive Rats.

The Vitis labrusca is a grapevine that has antioxidant, neuroprotective, hepatoprotective, and anticarcinogenic activity. However, the effect of Vitis labrusca leaves on the cardiovascular system is yet to be ascertained. The present study was designed to investigate the effects of Vitis labrusca leaves extract (HP1) on cardiovascular remodeling in spontaneously hypertensive rats. Experiments were performed in rats and were randomly divided into the following groups: Wistar Kyoto rat (WKY), normal control group; spontaneously hypertensive rats (SHR), negative control group; SHR + Losa, positive control group (losartan, 10 mg/kg/daily, AT1 receptor blocker) and SHR + HP1 (100 mg/kg/daily). HP1 was orally administered daily for 4 weeks. The HP1 treatment significantly improved blood pressure, electrocardiographic parameters, and echocardiogram parameters compared to hypertensive rats. Additionally, the left ventricular (LV) remodeling and LV dysfunction were significantly improved in HP1-treated hypertensive rats. Furthermore, an increase in fibrotic area has been observed in hypertensive rats compared with WKY. However, administration of HP1 significantly attenuated cardiac fibrosis in hypertensive rats. Moreover, HP1 suppressed the expression of high mobility group box 1 (HMGB1), toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), receptor for advanced glycation end products (RAGE), and extracellular signal-regulated kinases (ERK1/2) induced by hypertensive rats, resulting in improved vascular remodeling. Therefore, these results suggest that HP1 can improve the cardiovascular remodeling in hypertensive rats, and the mechanisms may be related to the suppressive effect of HP1 on HMGB1-TLR4-NFκB signaling in the cardiovascular system. Thus, the protective role of the traditional herbal medicine HP1 may provide new insights into the development of therapeutic drugs on the development of hypertensive cardiovascular dysfunction.

Abstract P209: Androgen Receptor Antagonist, Bicalutamide, And Androgen Receptor Degradation Enhancer, Asc-j9, Decrease Blood Pressure Similarly In Male Spontaneously-hypertensive Rats.

Background: Men are at greater risk for cardiovascular disease (CVD) than women until after menopause. For this reason, androgens have been implicated as playing a role in CVD in men. We have studied the role that androgens play in mediating the hypertension (HT) in spontaneously-hypertensive rats (SHRs), and found that blood pressure (BP) is decreased with castration and increased with testosterone supplements. In addition, we found that androgen receptor (AR) antagonists reduce BP, but blockers of the conversion of testosterone to dihydrotestosterone have no effect on BP, suggesting that testosterone alone is capable of mediating HT in male SHR. Testosterone is known to induce genomic and non-genomic effects via binding to nuclear AR or via independent mechanisms caused by membrane-bound AR. It is unclear whether or not membrane-bound AR play a role in mediating HT in male SHRs. In the present study we tested the hypothesis that only nuclear AR, not membrane-bound AR, mediate the HT in male SHR. Methods: Male SHR (aged 13 months; n = 5 - 6 rats/group) were implanted with radiotelemeters, and after 2 weeks recovery, mean arterial pressure (MAP) was measured for 4 days (baseline). Then rats were given vehicle (dimethylacetamide, DMA, 1 ml/kg, s.c.); bicalutamide (BICA, nuclear AR antagonist; 5 mg/k/d, s.c.); or Asc-j9 (AR degradation enhancer, 50 mg/kg/d, s.c.) for 8 days while measuring their MAP. Asc-j9 degrades both nuclear and membrane-bound AR. Results: Both BICA and Asc-j9 reduced MAP in male SHRs (BICA: 171 ± 2 to 151 ± 1 mmHg, p &lt; 0.05; Asc-j9: 172 ± 3 to 148 ± 2 mmHg, p &lt; 0.05.). DMA vehicle also reduced MAP (176 ± 5 to 161 ± 4 mmHg, p &lt; 0.05). The decrease in the BICA and Asc-j9 groups was significantly different than the DMA group. Conclusion: In summary, AR degradation enhancer, that degrades both membrane-bound and nuclear AR, reduced MAP to similar level as nuclear AR antagonist in male SHR, suggesting that it is the nuclear AR that plays a greater role in mediating chronic BP control in male SHR. It is likely that membrane-bound AR may mediate more acute effects of androgen function independent of the BP.

Inhibition of the NFATc4/ERK/AKT Pathway and Improvement of Thiol-Specific Oxidative Stress by Dronedarone Possibly Secondary to the Reduction of Blood Pressure in an Animal Model of Ventricular Hypertrophy.

Untreated chronic hypertension causes left ventricular hypertrophy, which is related to the occurrence of atrial fibrillation. Dronedarone is an antiarrhythmic agent recently approved for atrial fibrillation. Our group previously demonstrated that dronedarone produced an early regression of left ventricular hypertrophy after 14 days of treatment in an experimental study. In this study, we analyze the possible mechanisms responsible for this effect. Ten-month-old male spontaneously hypertensive rats (SHRs, n = 16) were randomly divided into therapy groups: SHR-D, which received dronedarone, and hypertensive controls, SHR, which received saline. Ten-month-old male Wistar Kyoto rats (WKY, n = 8), which also received a saline solution, were selected as normotensive controls. After 14 days of treatment, echocardiographic measurements of the left ventricle were performed, blood samples were collected for thiol-specific oxidative stress analysis, and the left ventricles were processed for western blot analysis. Dronedarone significantly lowered the left ventricular mass index and relative wall thickness compared with the SHR control group, and no differences were observed between the SHR-D group and the WKY rats. Interestingly, the SHR-D group showed significantly decreased levels of nuclear factor of activated T cells 4 (p-NFATc4), extracellular-signal-regulated kinase 1/2 (p-ERK1/2), and protein kinase B (p-AKT) compared with the hypertensive controls without statistical differences when compared with the WKY rats. Moreover, the SHR control group showed elevated thiolated protein levels and protein thiolation index (PTI) compared with the WKY rats. After treatment with dronedarone, both parameters decreased with respect to the SHR control group until reaching similar levels to the WKY rats. Our study suggests that dronedarone produces inhibition of the NFATc4/ERK/AKT pathway and improvement of thiol-specific oxidative stress possibly secondary to the reduction of blood pressure in an animal model of ventricular hypertrophy.

Icariin modulates eNOS activity via effect on post-translational protein-protein interactions to improve erectile function of spontaneously hypertensive rats.

Type 5 phosphodiesterase inhibitor (PDE5I) has become the first-line treatment for erectile dysfunction (ED). However, its effective rate for hypertension ED is only 60%-70%. How to improve the efficacy of ED treatment is the focus of current research. To explore whether icariin can improve the erectile function of spontaneously hypertensive rats (SHR) by affecting post-translational protein-protein interactions to regulate endothelial nitric oxide synthetase (eNOS) activity. Twelve-week-old healthy male SHR rats and Wistar-Kyoto rats (WKY) were randomly divided into four groups: SHR control group, SHR+icariin (10mg/kg·d gavage) treatment group, WKY control group, and WKY+icariin (10mg/kg·d gavage) treatment group (n=5). After 4weeks, the maximum penile intracavernous pressure/mean arterial pressure (ICPmax/MAP), the expression of heat-shock protein 90 (Hsp90), caveolin-1, calmodulin, p-eNOS, and eNOS in penile cavernous tissue and the content of nitric oxide (NO) and cGMP were measured. The interaction between eNOS and Hsp90, caveolin-1, and calmodulin were detected by immunoprecipitation. The ICPmax/MAP in the SHR+icariin treatment group (0.08±0.01, 0.23±0.07, 0.40±0.05) was significantly higher than the SHR group (0.03±0.01, 0.13±0.03, 0.21±0.02) under 3V and 5V electrical stimulations (P<.05). Compared with the SHR group, the expression of HSP90, calmodulin, P-eNOS, eNOS, and P-eNOS/eNOS in the penile cavernous tissue of rats in the WKY group and the SHR+icariin treatment group were significantly increased (P<.05), and the expression of caveolin-1 was significantly decreased (P<.05). The NO content (2.16±0.22μmol/g) and cGMP concentration (3.69±0.12pmol/mg) in the SHR+icariin treatment group were significantly higher than those in the SHR group (1.01±0.14μmol/g, 2.31±0.22pmol/mg) (P<.05). Compared with the SHR group, the interaction between eNOS and HSP90 in the cavernosa of the rats in the SHR+icariin treatment group was significantly increased (P<.05), the interaction between eNOS and caveolin-1 was significantly decreased (P<.01), and the interaction between eNOS and calmodulin did not significantly change. Up-regulating the expression of HSP90 and calmodulin and inhibiting caveolin-1 in SHR corpus cavernosum, promoting the interaction between eNOS and HSP90, inhibiting the interaction between eNOS and caveolin-1, increasing p-eNOS/eNOS, may be the mechanism of icariin that improves SHR erectile function.

Antihypertensive Effects of Polyphenolic Extract from Korean Red Pine (Pinus densiflora Sieb. et Zucc.) Bark in Spontaneously Hypertensive Rats.

Korean red pine (Pinus densiflora Sieb. et Zucc.) bark is a by-product of the wood industry and contains a high level of antioxidative phenolics including flavonoids, which have a variety of beneficial health effects. This study aimed to investigate the antihypertensive effects of P. densiflora bark extract (Korean red pine bark extract; KRPBE) in spontaneously hypertensive rats (SHRs). A group of Wistar-Kyoto rats as a normotensive group was orally fed tap water. Four groups of SHRs were orally fed tap water, captopril (a positive control), 50 mg/kg/day of KRPBE, and 150 mg/kg/day of KRPBE, respectively. Blood pressure of rats was measured once every week for seven weeks of oral administration. After seven weeks, the lungs, kidneys, and serum were collected from rats, then angiotensin-converting enzyme (ACE) activity, angiotensin II content, and malondialdehyde (MDA) content were determined. Blood pressure of the captopril- and KRPBE-treated groups was significantly lower than that of the SHR control group. The ACE activity, angiotensin II content, and MDA content significantly decreased in the captopril- and KRPBE-treated groups than those in the SHR control group. High-performance liquid chromatography analysis revealed six phenolics in KRPBE: protocatechuic acid, procyanidin B1, catechin, caffeic acid, vanillin, and taxifolin. KRPBE, which contains plenty of antioxidative phenolics, has antihypertensive effects partly due to reduction of ACE activity and angiotensin II content, and its antioxidative effect.

Salvianolic Acid Alleviated Blood-Brain Barrier Permeability in Spontaneously Hypertensive Rats by Inhibiting Apoptosis in Pericytes via P53 and the Ras/Raf/MEK/ERK Pathway.

ObjectiveTo investigate the effect of salvianolic acid A (SA) on the permeability of blood–brain barrier (BBB) and brain microvascular pericyte apoptosis in spontaneously hypertensive rats (SHR).MethodsEvans Blue was used to determine the BBB permeability in control rats and SHR. Western blotting was used to evaluate the expression levels of relevant proteins in the pericytes isolated from the differentially treated animals. An in vitro model of hypertension was established by stimulating pericytes with angiopoietin-2 (Ang2). MTT assay was used to assess cell viability, and apoptosis and cell cycle distribution were analyzed by flow cytometry.ResultsSA attenuated BBB permeability in SHR in a dose-dependent manner. It downregulated pro-apoptotic proteins including p53, p21, Fas, FasL, cleaved-caspase 3/caspase 3 and Bax in the pericytes of SHR and upregulated CDK6, cyclin D1, CDK2, cyclin E and Bcl2. In addition, SA activated the Ras/Raf/MEK/ERK pathway in a dose-dependent manner by increasing the levels of Ras, Raf, p-MEK1, p-MEK2, p-ERK1 and p-ERK2. Finally, SA reduced Ang2-induced apoptosis of cerebral microvessels pericytes and decreased the proportion of cells in the G0/G1 phase of the cell cycle by inhibiting the p53 pathway and activating the Ras/Raf/MEK/ERK pathway.ConclusionSA reduced BBB permeability in spontaneously hypertensive rats, possibly by inhibiting Ang2-induced apoptosis of pericytes by activating the Ras/Raf/MEK/ERK pathway.

Early Postnatal Gut Microbiota Determines SHR Hypertension

Hypertension is regulated by immunological components. We have shown that spontaneously hypertensive rats (SHR) display a genetic abnormality in a large population of proinflammatory CD161+ immune cells. Although early postnatal gut microbiota is important for development of the immune system, this relationship has not been studied in hypertension. Cross‐fostering SHR pups by normotensive Wistar‐Kyoto (WKY) dams lowers the blood pressure in adulthood when cross‐fostering is initiated at a very young age. In this study, we tested whether early alteration in postnatal gut microbiota affect s the immune system and blood pressure of SHR. We first examined the microbial populations in the fecal samples of SHR and normotensive control WKY using 16s rDNA sequencing. We found that the newborn SHR (1‐week old) have abnormal gut microbiota that is qualitatively and quantitatively different from the newborns of normotensive WKY. The representation of the predominant bacterial phylum Proteobacteria was significantly less in 1‐week old SHR pups than in WKY (94% Proteobacteria in WKY vs. 65% in SHR neonates). Even within the phylum Proteobacteria, the colonizing genera in WKY and SHR differed dramatically. Whereas WKY microbiota was predominantly comprised of Escherichia‐Shigella (92.5%), SHR microbiota was represented by Klebsiella (34.7%) and Haemophilus (27.8%). In contrast, the representation of phylum Fermicutes in the neonatal SHR gut was greater than WKY (5% Fermicutes in WKY vs. 31% in SHR). We cross‐fostered newborn SHR pups by lactating WKY dams and measured the resulting changes in the gut microbiota, immune system and blood pressure. Cross‐fostering caused a dramatic shift in 1‐week old cross‐fostered SHR gut microbiota. The two major bacterial genera of phylum Proteobacteria, Klebsiella and Haemophilus, present in self‐fostered SHR pups, were depleted after cross‐fostering, and were replaced by the predominant genera of WKY (Escherichia‐Shigella). A proinflammatory CD161+ immune cell population in the spleen of cross‐fostered SHR was also reduced (30.7% in self‐fostered SHR vs. 12.6% in cross‐fostered SHR at 30 weeks of age) as was the systolic blood pressure in adult cross‐fostered SHR (SHR 204 mmHg vs. cross‐fostered SHR 177 mmHg, p= 0.02, n= 4 each group). Thus, cross‐fostering of SHR pups by WKY dams shifted the composition of their gut microbiota toward WKY within one week. Additionally, reduction in proinflammatory immune cells and lowering of systolic blood pressure were observed in cross‐fostered SHR. In summary, SHR have a congenital defect in their immune system that results in greater proinflammatory response associated with hypertension. Gut microbiota of the SHR is remarkably different from that of normotensive WKY, and likely contributes to SHR blood pressure by modulating early development of the immune system.Support or Funding InformationNational Institutes of Health Program Project Grant to FMA (HL 14388) VA Merit Review Award to MWC (1 I01BX001414), American Heart Association Innovative Research Grant to MVS (16IRG27260323).

Probiotics Prevent Dysbiosis and the Rise in Blood Pressure in Genetic Hypertension: Role of Short-Chain Fatty Acids.

The objective of this study is to determine the cardiovascular effects of the probiotics Bifidobacterium breve CECT7263 (BFM) and Lactobacillus fermentum CECT5716 (LC40), and the short chain fatty acids butyrate, and acetate in spontaneously hypertensive rats (SHR). Ten five-week old Wistar Kyoto rats (WKY) and fifty aged-matched SHR are randomly distributed into six groups: control WKY, control SHR, treated SHR-LC40, treated SHR-BMF, treated SHR-butyrate, and treated SHR-acetate. Chronic treatments with LC40 or BFM increase butyrate-producing bacteria and prevent the blood pressure increase in SHR. Oral treatment with butyrate or acetate also prevents the increase in both blood pressure and Firmicutes/Bacteroidetes (F/B) ratio. All treatments restore the Th17/Treg balance in mesenteric lymph nodes, normalized endotoxemia, and prevent the impairment of endothelium-dependent relaxation to acetylcholine, as a result of reduced NADPH oxidase-driven reactive oxygen species production. These protective effects might be mediated by both the reduction in vascular lipopolysaccharide (LPS)/toll-like receptor 4 (TLR4) pathway and the increase in Treg infiltration in the vasculature. The probiotics LC40 and BFM prevent dysbiosis and the development of endothelial dysfunction and high blood pressure in genetic hypertension. These effects seem to be related to endotoxemia reduction and to increase Treg accumulation in the vasculature.

JnK inhibitor 11H-indeno [1,2-b]chinoxalin-11-on-oxim sodium salt reduces the development of diastolic dysfunction in spontaneously hypertensive rats

Background. In arterial hypertension (HTN), diastolic dysfunction (DD) of the left ventricle (LV) makes a major contribution to the development of heart failure, so the treatment of DD is an important task. The role of the JNK-dependent pathway in myocardial remodeling in HTN is shown. Objective. To evaluate the effect of the new JNK inhibitor IQ-1S (11H-indeno [1,2-b]quinoxalin-11-one oxime sodium salt) on parameters of cardiac activity in SHR rats during the period of stable HTN and the formation of DD. Design and methods . The experiments were carried out on 5 normotensive Wistar-Kyoto (WKY) rats and 10 spontaneously hypertensive rats (SHRs); the experiments included animals that reached the age of 12 weeks. IQ- 1S (50 mg/kg) was administered intragastrically daily to the SHRs of the experimental group (n = 5) for 6 weeks. The WKY control animals (n = 5) and the SHRs (n = 5) received an equivolume amount of distilled water. Systolic blood pressure (SBP) was measured before and after the course of IQ-1S. At the end of the IQ-1S course, body mass (BM) and left ventricular mass (LVM) were evaluated, and contractile myocardial activity (intracardiac sensor) was recorded. Results. Before and after the IQ-1S course, the values of SBP in the control SHRs were higher than in WKY rats by 30 % and 53 %. After the administration of IQ-1S SHRs showed significantly lower SBP (by 13 %), the LVM/BM index (by 5 %) and the end-diastolic LV pressure (by 40 %) compared to the control SHRs. Conclusions. Our results confirm the ability of the JNK inhibitor IQ-1S to reduce blood pressure, myocardial hypertrophy and suppress the development of diastolic LV dysfunction in SHRs with the stable HTN.

Suppression of tooth movement-induced sclerostin expression using β-adrenergic receptor blockers.

Regulation of bone metabolism by the sympathetic nervous system has recently been clarified. Tooth movement is increased by increased bone metabolic turnover due to sympathetic activation. This study aimed to compare the effects of the β-adrenergic receptor (β-AR) blockers atenolol (β1-AR blocker), butoxamine (β2-AR blocker) and propranolol (non-selective β-AR blocker) on tooth movement in spontaneously hypertensive rats (SHR) with sympathicotonia. Spontaneously hypertensive rats were divided into the following four groups: an SHR control group and groups treated with 0.1mg/kg atenolol, 1mg/kg butoxamine or 1mg/kg propranolol (n=6 rats/group). Atenolol, butoxamine or propranolol was administered daily to each treatment group, and orthodontic force was applied using a closed-coil spring. Finally, immunohistochemical analysis was performed for receptor activator of nuclear factor kappa-B ligand (RANKL) and sclerostin (SOST). Atenolol, butoxamine and propranolol inhibited tooth movement and increased maxillary alveolar bone volume. Histological analysis revealed that these β-AR blockers decreased osteoclast activity on the compression side. Furthermore, immunohistochemical analysis revealed that atenolol, butoxamine and propranolol decreased the number of RANKL- and SOST-positive osteocytes on the compression side. β-AR blockers decreased tooth movement and downregulated SOST in osteocytes, accompanied by increasing alveolar bone resorption.

Efficacy of programmed labor protocol in providing shorter, safer and a relatively pain free delivery

Introduction: Labor is a multifactorial spontaneous process, which involves myometrial contractions, cervical ripening and dilatation, expulsion of the fetus in an orderly manner with minimal aids. The thought of labor produces anguish and apprehension in women. In an attempt to overcome the same this indigenously developed protocol for parturient women was designed to make labor a pleasant experience. Materials and Methods: This was a prospective randomized clinical trial. Total of 100 parturient women at term in active labor who attended labor room, GSL Medical College & Hospital, Rajahmundry were admitted between April 2013 to March 2014. The study group received programmed labor protocol and control group managed expectantly. All were low risk primigravid women. The women entered the study after taking an informed and written consent. Result: Mean duration of Active phase was 3.47.24 hrs&5.61 .21hrs in study and controls respectively. Mean cervical dilatation rate was 3.05 .58 cm/ hr in study and 1.15.05cm/ hrin controls. Complications seen during labor in the study group were prolonged 2nd stage in 4(8%). One had dilatation of arrest at 5cms for almost 4hrs and underwent LSCS. One had fetal distress at full dilatation and delivered by forceps.88% had no complications. Conclusion: Programmed labor group had faster cervical dilatation, shorter labors, excellent pain relief, No impact on LSCS rates, No compromise on Maternal or Neonatal safety. It reduces laboring women’s anxiety, apprehension associated with labor and makes it a pleasant and memorable event. It can be used as routine protocol in low risk gravid women at least in institution. Keywords: Programmed labor protocol, Low risk primigravid women, Duration of labor, APGAR score.

Chronic Mercury Exposure in Prehypertensive SHRs Accelerates Hypertension Development and Activates Vasoprotective Mechanisms by Increasing NO and H2O2 Production.

Mercury is a heavy metal associated with cardiovascular diseases. Studies have reported increased vascular reactivity without changes in systolic blood pressure (SBP) after chronic mercury chloride (HgCl2) exposure, an inorganic form of the metal, in normotensive rats. However, we do not know whether individuals in the prehypertensive phase, such as young spontaneously hypertensive rats (SHRs), are susceptible to increased arterial blood pressure. We investigated whether chronic HgCl2 exposure in young SHRs accelerates hypertension development by studying the vascular function of mesenteric resistance arteries (MRAs) and SBP in young SHRs during the prehypertensive phase. Four-week-old male SHRs were divided into two groups: the SHR control group (vehicle) and the SHR HgCl2 group (4weeks of exposure). The results showed that HgCl2 treatment accelerated the development of hypertension; reduced vascular reactivity to phenylephrine in MRAs; increased nitric oxide (NO) generation; promoted vascular dysfunction by increasing the production of reactive oxygen species (ROS), such as hydrogen peroxide (H2O2); increased Gp91Phox protein levels and in situ levels of superoxide anion (O2·-); and reduced vasoconstrictor prostanoid production compared to vehicle treatment. Although HgCl2 accelerated the development of hypertension, the HgCl2-exposed animals also exhibited a vasoprotective mechanism to counterbalance the rapid increase in SBP by decreasing vascular reactivity through H2O2 and NO overproduction. Our results suggest that HgCl2 exposure potentiates this vasoprotective mechanism against the early establishment of hypertension. Therefore, we are concluding that chronic exposure to HgCl2 in prehypertensive animals could enhance the risk for cardiovascular diseases.