Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085580 (essential hypertension)
 14,686 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previous studies have demonstrated that elevated plasma leptin concentrations are associated with essential hypertension. It has also recently been shown that leptin plays a promoting role in angiogenesis, and the vascular endothelium expresses the long form of leptin receptor. Those data led us to hypothesize that leptin might contribute to end-organ damage in hypertension. Thus, in the present study we evaluated the relationship between plasma leptin concentrations and hypertensive retinopathy (HR). One hundred and eleven patients newly diagnosed with essential hypertension [EHT; mean age, 43.5 +/-10.7 yr; body mass index (BMI), 28.1 +/- 4.4 kg/m2; male/female ratio, 71/40] and 79 healthy normotensive control subjects (NT; mean age, 43.6 +/- 9.2 yr; BMI, 28.2 +/- 3.3 kg/m2; male/female ratio, 50/29) were enrolled in the study. For the assessment of retinopathy according to the Keith-Wagener classification, direct and indirect ophthalmoscopy were performed in all subjects after dilatation of the pupils. Plasma leptin levels were significantly higher in EHT (11.8 +/- 11.1 ng/mL) than in NT (7.2 +/- 5.1 ng/mL) (P = 0.003). Plasma leptin concentrations were strongly correlated with BMI in both EHT (r = 0.45; P = 0.001) and NT (r = 0.38; P = 0.001) groups. Plasma leptin in patients with grade 2 HR (24.8 +/- 15.8 ng/mL; n = 22) was significantly higher than that in patients with grade 1 HR (16.1 +/- 4.9 ng/mL; n = 29; P = 0.001), grade 0 HR (5.1 +/- 3.1 ng/mL; n = 60; P = 0.001), and NT (P = 0.001). Plasma leptin in patients with grade 1 HR was also significantly higher than that in patients without retinopathy (P = 0.001) or in NT (P = 0.001). The estimated threshold of plasma leptin concentration for HR was 10.2 ng/mL. This critical leptin level served largely to separate patients with retinopathy from those without retinopathy. In summary, our results show that plasma leptin concentrations increase progressively with higher grades of hypertensive retinopathy even after correction for BMI, suggesting that a critical leptin level is needed for the development of retinopathy. Elevated concentrations of plasma leptin might be secondary to release of leptin by the vascular endothelium damaged by high blood pressure, as an epiphenomenon. However, a pathogenic role for leptin in hypertensive retinopathy cannot be excluded.
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PMID:Is leptin associated with hypertensive retinopathy? 1069 Aug 76

Five candidate genes including the lipoprotein lipase, leptin, leptin receptor, alpha-adducin and beta3 adrenergic receptor were selected to examine their possible contribution to essential hypertension (EH) in a Chinese population. On each side of the candidate gene loci, one to two highly polymorphic microsatellite markers were genotyped in 474 subjects recruited from 106 hypertension nuclear families in Shanghai. Both parametric and nonparametric linkage analyses were carried out using GENEHUNTER (version 2.0) after genotyping. Extended transmission disequilibrium testing (ETDT) was also conducted to detect preferential transmission of alleles to affected offspring. We failed to find the linkage between all these loci and EH by either parametric or nonparametric analysis, nor did we detect any significant transmission disequilibrium by ETDT. Our findings provide no support for a significant contribution of these five genes to the pathogenesis of EH among Shanghai people.
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PMID:Linkage analysis of five candidate genes and essential hypertension in 106 Chinese nuclear families. 1257 19

Obesity-induced hypertension and essential hypertension in lean patients are two different forms of hypertension. The main goal of this study was to test whether there are differences in biochemical parameters between subjects with obesity-associated hypertension and those with essential hypertension. We examined whether the biochemical responses to angiotensin-converting enzyme inhibitor (ACEI) ramipril therapy reveal properties of these two conditions that might explain the differences in clinical outcome. Before ramipril therapy, the hypertensive group exhibited increases in ACE activity (p<0.05), plasma malondialdehyde (MDA) concentration and the malondialdehyde/nitric oxide end-product ratio (MDA/NO(x)) (p<0.05), and decreases in xanthine oxidase (XO) activity (p<0.05) and plasma nitric oxide end-product (NO(x)) level (p<0.01). Before medication, plasma endothelin-1 (ET-1), plasma leptin, and leptin receptor levels were normal. Following ramipril treatment, ACE activity normalized. Before ACE inhibitor treatment, the obese-hypertensive group exhibited elevated levels of plasma ET-1 (p<0.05), plasma leptin (p<0.01), XO activity (p<0.05), plasma MDA and MDA/NO(x) (p<0.05), and reduced levels of plasma NO(x)(p<0.01) and leptin receptors (p<0.001). Following medication, the plasma NO(x) level, MDA/NO(x), and XO activity returned to normal while ACE activity decreased (p<0.001). In patients with essential hypertension, NO availability and ACE activity, and in those with obesity-associated hypertension, hyperleptinemic effects, NO level, endothelin-1 concentration and XO activity, may be important factors in the pathology.
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PMID:Different pathomechanisms of essential and obesity-associated hypertension in adolescents. 1689 99

Essential hypertension is associated with increased plasma leptin levels and decreased human soluble leptin receptor (hsLR) concentration. The aim of this study was to determine whether the concentration of hsLR differs among offspring of hypertensive compared with nonhypertensive parents. Subjects in the 2 groups were matched for age, sex, and body mass index. Forty-six (24 male, 22 female; mean age, 18+/-3 years; body mass index, 22.4+/-1.4 kg/m2) healthy offspring of hypertensive parents (group A) and 50 (28 male, 22 female; mean age, 18+/-3.2 years; body mass index, 22.6+/-1.7 kg/m2) healthy offspring of healthy parents (group B) were studied. The hsLR concentration (enzyme-linked immunosorbent assay method) and leptin plasma levels (radioimmunoassay method) were determined in the study population. Plasma leptin levels were significantly higher (10+/-5 vs 6+/-3 ng/mL; P<.001), while hsLR concentration was significantly lower (20+/-7 vs 29+/-8 U/mL; P<.001) in group A compared with group B. Our findings suggest that offspring of hypertensive parents have significantly higher plasma leptin levels and significantly lower hsLR concentrations compared with healthy offspring of healthy normotensive parents. Further studies are needed to determine the clinical significance of these observations.
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PMID:Human soluble leptin receptor concentration in healthy offspring of hypertensive parents. 1708 20

Renin-angiotensin system, metabolic abnormalities, and immune activity have a role in the pathogenesis of primary hypertension. We assessed the leukocyte mRNA expression of angiotensinogen, angiotensin converting enzyme, renin, angiotensin 2 type 1 receptor, CD14 molecule, adiponectin type 1 receptor, and leptin receptor in hypertensive children before and after nonpharmacological treatment. Leukocyte mRNA expression was measured by means of quantitative real-time reverse transcriptase-polymerase chain reaction in 23 hypertensive children before and after 6 months of nonpharmacological treatment based on dietary advice and physical activities. Twenty-three normotensive children matched for age, sex, and body mass index served as a control group. Before treatment patients had elevated expression of angiotensin converting enzyme and CD14 mRNA, decreased expression of angiotensinogen and angiotensin type 1 receptor mRNA, and unchanged expression of renin, adiponectin, and leptin receptors mRNA as compared with controls. Renin mRNA negatively correlated with 24-hour mean arterial pressure and carotid intima-media thickness. Six months of nonpharmacological treatment caused decrease of blood pressure and normalization of metabolic abnormalities. Renin, adiponectin, and leptin receptors mRNA expression decreased and were lower than in control group. Changes in blood pressure, left ventricular mass, carotid intima-media thickness, body mass index, and waist circumference did not correlate with changes in the expression of renin-angiotensin system genes, CD14, leptin, and adiponectin receptors mRNA. We conclude that leukocytes of hypertensive children displayed alterations in the expression of renin-angiotensin system genes as well as those of CD14. Nonpharmacological treatment resulted in downregulation of genes involved in renin-angiotensin activation and those engaged in leukocyte responses to adipokines.
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PMID:Altered genes profile of renin-angiotensin system, immune system, and adipokines receptors in leukocytes of children with primary hypertension. 2326 43

In order to explore the potential association between the leptin receptor (LEPR) gene polymorphisms and essential hypertension (EH) risk in the Northern Han Chinese population, we recruited 823 hypertensive subjects and 491 healthy control subjects from the Northern Han Chinese. Genotyping was performed to identify the Lys109Arg, Gln223Arg and Lys656Asn polymorphisms of the LEPR gene. Significant associations were found in a dominant genetic model ([GG+AG] vs. AA), P=0.007, odds ratio (OR)=3.697, 95% confidence interval (CI) 1.442-9.482), and in homozygote comparison (GG vs. AA, P=0.005, OR=3.890, 95% CI 1.501-10.077) for the Gln223Arg polymorphism. No significant association could be found between Lys109Arg or Lys656Asn polymorphism and EH risk. Linkage disequilibrium was detected between the Lys109Arg and Gln223Arg polymorphisms, and haplotype analyses identified that the G-A haplotype was a protective haplotype for EH. Our studies demonstrated that the LEPR Gln223Arg polymorphism had an important role in a patient's susceptibility to EH in the Northern Han Chinese population.
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PMID:Role of leptin receptor gene polymorphisms in susceptibility to the development of essential hypertension: a case-control association study in a Northern Han Chinese population. 2452 42

The adipokine leptin is expressed at higher concentrations in obese subjects, who also incidentally have a higher prevalence of hypertension. The pathogenesis of this obesity-related hypertension is controversial and is believed to be related to many factors including increased sympathetic activity, abnormalities of the renin-angiotensin system, sodium retention, and an endotheliopathy acting independently or in concert with increased circulating leptin. This review discusses the potential mechanisms through which changes in leptin signal transduction pathways in tissues with the leptin receptor, especially the hypothalamus, mediate the pathogenetic relationships between obesity and hypertension. The hypothesis is explored that leptin effects on blood pressure (BP) are meditated by the downstream effects of hypothalamic leptin signaling and ultimately result in activation of specific melanocortin receptors located on sympathetic neurons in the spinal cord. The physiological consequences of this sympathetic activation of the heart and kidney are activation of the renin-angiotensin system, sodium retention and circulatory expansion and finally, elevated BP. This sequence of events has been elegantly demonstrated with leptin infusion and gene knockout studies in animal models but has not been convincingly reproducibly confirmed in humans. Further studies in human subjects on the specific roles of hypothalamic leptin in essential hypertension are indicated as elucidation of the signaling pathways should provide better understanding of the role of weight loss in BP control and afford an additional mechanism for pharmacologic control of BP in adults and children at risk of cardiovascular disease.
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PMID:Leptin, Obesity, and Hypertension: A Review of Pathogenetic Mechanisms. 3287 6