Augmentation of Nitric Oxide Deficient Hypertension by High Salt Diet Is Associated With Reduced TNF-α Receptor Type 1 Expression in the Kidneys.

BACKGROUND: High salt (HS) intake induces an augmented hypertensive response to nitric oxide (NO) inhibition, though it causes minimal changes in blood pressure (BP) in NO intact condition. The cause of such augmentation is not known. HS induces tumor necrosis factor-alpha (TNFα) production that causes natriuresis via activation of its receptor type 1 (TNFR1). We hypothesized that NO deficiency reduces renal TNFR1 activity, leading to enhanced sodium retention and hypertension. METHODS: We examined the changes in renal TNFR1 protein expression (Immunohistochemistry analyses) after HS (4% NaCl) intake in wild-type mice (WT, C57BL6) treated with a NO synthase (NOS) inhibitor, nitro-l-arginine methyl ester (L-NAME; 0.05 mg/min/g; osmotic mini-pump), as well as in endothelial NOS knockout mice (eNOSKO) and compared the responses in WT mice with normal salt (NS; 0.3% NaCl) intake. BP was measured with tail-cuff plethysmography and 24-hour urine collections were made using metabolic cages. RESULTS: HS alone did not alter mean BP in untreated mice (76 ±â€…3 to 77 ±â€…1 mm Hg) but induced an augmented response in L-NAME treated (106 ±â€…1 vs. 97 ±â€…2 mm Hg) and in eNOSKO (107 ±â€…2 vs. 89 ±â€…3 mm Hg) mice. The percentage area of TNFR1 expression in renal tissue was higher in WT + HS (4.1 + 0.5%) than in WT + NS mice (2.7 ±â€…0.6%). However, TNFR1 expression was significantly lower in L-NAME treated WT + NS (0.9 ±â€…0.1%) and in eNOSKO + NS (1.4 ±â€…0.2%) than in both WT + NS and WT + HS mice. CONCLUSIONS: These data indicate that TNFR1 activity is downregulated in NO deficient conditions, which facilitates salt retention leading to augmented hypertension during HS intake.

Role of preservation methods using deep-freezing and liquid nitrogen in bone allograft characteristics: An in vitro study.

Bone grafting has emerged as a key solution in bone defect management such as allograft, graft of bone from another individual. However, bone allografts usually undergo rigorous preparation to eliminate immune-triggering elements. The deep-freezing methods may delay graft use, while cryopreservation using liquid nitrogen allows rapid freezing but may alter graft characteristics. The aim of this study was to investigate the post-preservation changes in bone allograft characteristics and to compare the effectiveness of deep-freezing and liquid nitrogen methods using animal model. An experimental study using a post-test only control group design was conducted. Fresh-frozen femoral cortical bone was obtained from male New Zealand white rabbits. Preservation by deep-freezing involved placing bone samples in a -80°C freezer for 30 days. For liquid nitrogen preservation, bone grafts were immersed in liquid nitrogen for 20 min, followed by a 15-min rest at room temperature and a final immersion in 0.9% sodium chloride at 30°C for 15 min. Bone samples then underwent evaluation of cell viability, compression, and bending tests. Cell viability test employed the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and the compression and bending tests used the Universal Testing Machine (UTM). Independent Student t-test or Mann-Whitney U test were used to compare the methods as appropriate. Our study found that the use of deep-freezing and liquid nitrogen resulted in similar outcomes for cell viability, compression, and bending tests, with p-values of 0.302, 0.745, and 0.512, respectively. Further exploration with larger sample sizes may help to optimize the methods for specific applications.

Continuum of care and longitudinal recovery in a 17-year-old athlete with second impact syndrome.

Second impact syndrome (SIS) is an uncommon, but devastating sports-related structural brain injury that results from a second head injury before complete recovery from an initial concussion. The pathophysiology of second impact syndrome is poorly understood, but is hypothesized to involve loss of autoregulation, diffuse cerebral edema, with progression to rapid brain herniation syndromes. Here, we present a case of second impact syndrome in an adolescent high school football player who experienced acute brain herniation and coma. Following stabilization, the patient underwent comprehensive, multidisciplinary rehabilitation in order to achieve significant recovery. A narrative detailing the patient's recovery from one-year post-injury is reviewed.

Personal exposure to household air pollution and lung function in rural Bangladesh: A population-based cross-sectional study.

We assessed whether personal exposure to household air pollution [PM2.5 and black carbon (BC)] is associated with lung functions (FEV1, FVC, and their ratio) in non-smoking adults in rural Bangladesh. We measured personal exposure to PM2.5 using gravimetric analysis of PM2.5 mass and BC by reflectance measurement between April 2016 and June 2019. The average 24-hour PM2.5 and BC concentration was 141.0µgm-3 and 13.8µgm-3 for females, and 91.7 µgm-3 and 10.1 µgm-3 for males, respectively. A 1 µgm-3 increase in PM2.5 resulted in a 0.02 ml reduction in FEV1, 0.43 ml reduction in FVC, and 0.004% reduction in FEV1/FVC. We also found a similar inverse relationship between BC and lung functions (9.6 ml decrease in FEV1 and 18.5 ml decrease in FVC per 1µgm-3 increase in BC). A higher proportion of non-smoking biomass fuel users (50.1% of the females and 46.7% of the males) had restrictive patterns of lung function abnormalities, which need further exploration.

Angiotensin II-induced renal angiotensinogen formation is enhanced in mice lacking tumor necrosis factor-alpha type 1 receptor.

In hypertension induced by angiotensin II (AngII) administration with high salt (HS) intake, intrarenal angiotensinogen (AGT) and tumor necrosis factor-alpha (TNF-α) levels increase. However, TNF-α has been shown to suppress AGT formation in cultured renal proximal tubular cells. We examined the hypothesis that elevated AngII levels during HS intake reduces TNF-α receptor type 1 (TNFR1) activity in the kidneys, thus facilitating increased intrarenal AGT formation. The responses to HS diet (4% NaCl) with chronic infusion of AngII (25 ng/min) via implanted minipump for 4 weeks were assessed in wild-type (WT) and knockout (KO) mice lacking TNFR1 or TNFR2 receptors. Blood pressure was measured by tail-cuff plethysmography, and 24-h urine samples were collected using metabolic cages prior to start (0 day) and at the end of 2nd and 4th week periods. The urinary excretion rate of AGT (uAGT; marker for intrarenal AGT) was measured using ELISA. HS +AngII treatment for 4 weeks increased mean arterial pressure (MAP) in all strains of mice. However, the increase in MAP in TNFR1KO (77 ± 2 to 115 ± 3 mmHg; n = 7) was significantly greater (p < 0.01) than in WT (76 ± 1 to 102 ± 2 mmHg; n = 7) or in TNFR2KO (78 ± 2 to 99 ± 5 mmHg; n = 6). The increase in uAGT at 4th week was also greater (p < 0.05) in TNFR1KO mice (6 ± 2 to 167 ± 75 ng/24 h) than that in WT (6 ± 3 to 46 ± 16 ng/24 h) or in TNFR2KO mice (8 ± 7 to 65 ± 44 ng/24 h). The results indicate that TNFR1 exerts a protective role by mitigating intrarenal AGT formation induced by elevated AngII and HS intake.

Angiotensin II-induced natriuresis is attenuated in knockout mice lacking the receptors for tumor necrosis factor-α.

Intravenous infusion of relatively higher doses of angiotensin II (AngII) elicits natriuresis as opposed to its usual anti-natruretic response. As AngII can induce tumor necrosis factor-α (TNFα) production which elicits natriuresis via its action on TNFα receptor type 1 (TNFR1), we hypothesize that the concomitant release of TNFα contributes to the natriuretic response to AngII. Responses to AngII infusion (1 ng min-1  g-1 for 75 min, iv) were evaluated in anesthetized knockout (KO) mice lacking TNFR1 (n = 6) and TNFR2 (TNFα receptor type 2; n = 6) and compared these responses with those in wild type (WT; n = 6) mice. Arterial pressure (AP) was recorded from a cannula placed in the carotid artery. Renal blood flow (RBF) and glomerular filtration rate (GFR) were measured by PAH and inulin clearances, respectively. Urine was collected from a catheter placed in the bladder. AngII caused similar increases (p < 0.05 vs basal values) in AP (WT, 37 ± 5%; TNFR1KO, 35 ± 4%; TNFR2KO, 30 ± 4%) and decreases (p < 0.05) in RBF (WT, -39 ± 5%; TNFR1KO, -28 ± 6%; TNFR2KO, -31 ± 4%) without significant changes in GFR (WT, -17 ± 7%; TNFR1KO, -18 ± 7%; TNFR2KO, -12 ± 7%). However, despite similar changes in AP and renal hemodynamics, AngII induced increases (p < 0.05) in urinary sodium excretion in WT (3916 ± 942%) were less in the KO strains, more or less in TNFR1KO (473 ± 170%) than in TNFR2KO (1176 ± 168%). These data indicate that TNF-α receptors, particularly TNFR1 are involved in the natriuretic response that occur during acute infusion of AngII and thus, plays a protective role in preventing excessive salt retention at clinical conditions associated with elevated AngII level.

Exposure to household air pollutants and endothelial dysfunction in rural Bangladesh: A cross-sectional study.

More than one third of world's population use biomass fuel for cooking that has been linked to an array of adverse health hazards including cardiovascular mortality and morbidity. As part of Bangladesh Global Environmental and Occupational Health (GEO Health) project, we assessed whether household air pollution (HAP) was associated with dysfunction in microvascular circulation (measured by reactive hyperemia index [RHI]). METHODS: We measured exposure to HAP (particulate matter [PM2.5], carbon monoxide [CO], and black carbon [BC]) for 48 hours of 200 healthy nonsmoker adult females who used biomass fuel for cooking. Exposure to PM2.5 and BC were measured using personal monitor, RTI MicroPEM (RTI International, NC) with an internal filter that had been both pre- and post-weighed to capture the deposited pollutants concentration. Lascar CO logger was used to measure CO. Endothelial function was measured by forearm blood flow dilatation response to brachial artery occlusion using RHI based on peripheral artery tonometry. A low RHI score (<1.67) indicates impaired endothelial function. RESULTS: Average 48 hours personal exposure to PM2.5 and BC were 144.15 µg/m3 (SD 61.26) and 6.35 µg/m3 (SD 2.18), respectively. Interquartile range for CO was 0.73 ppm (0.62-1.35 ppm). Mean logarithm of RHI (LnRHI) was 0.57 in current data. No statistically significant association was observed for LnRHI with PM2.5 (odds ratio [OR] = 0.97; 95% confidence interval [CI] = 0.92, 1.01; P = 0.16), BC (OR = 0.85; 95% CI = 0.72, 1.01; P = 0.07), and CO (OR = 0.89; 95% CI = 0.64, 1.25; P = 0.53) after adjusting for potential covariates. CONCLUSIONS: In conclusion, HAP was not associated with endothelial dysfunction among nonsmoking females in rural Bangladesh who used biomass fuel for cooking for years.

High-salt intake reduces renal tissue levels of inflammatory cytokines in mice.

High salt (HS) intake is usually considered as an aggravating factor to induce inflammatory renal injury. However, the changes in the renal levels of inflammatory cytokines during HS intake is not yet clearly defined. We hypothesize that HS increases renal levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) but decreases interleukin-10 (IL-10; anti-inflammatory cytokine) and these responses exacerbate in NO deficient conditions. Both wild-type (WT) and endothelial NO synthase knockout (eNOSKO) mice (~8 weeks old, n = 6 in each group) were given normal-salt (NS; 0.3% NaCl) and HS (4% NaCl) containing diets for 2 weeks. Systolic blood pressure (SBP) was determined by tail-cuff plethysmography and urine collections were made using metabolic cages. Basal SBP was higher in eNOSKO than WT mice (131 ± 7 vs 117 ± 3 mmHg; p < .05). HS intake for 2 weeks increased SBP in eNOSKO (161 ± 5 mmHg) but not in WT mice. In NS groups, the cytokine levels in renal tissues (measured using ELISA kits and expressed in pg/mg protein) were significantly higher in eNOSKO than WT mice (TNF-α, 624 ± 67 vs. 325 ± 73; IL-6, 619 ± 106 vs. 166 ± 61; IL-10, 6,087 ± 567 vs. 3,929 ± 378). Interestingly, these cytokine levels in HS groups were significantly less both in WT (TNF-α, 114 ± 17; IL-6, 81 ± 14; IL-10, 865 ± 130) and eNOSKO (TNF-α, 115 ± 18; IL-6, 56 ± 7; IL-10, 882 ± 141) mice. These findings indicate that HS induces downregulation of cytokines in the kidney. Such HS-induced reduction in cytokines, particularly TNF-α (a natriuretic agent), would facilitate more salt-retention, and thus, leading to salt-sensitive hypertension in NO deficient conditions.

Low Nitric Oxide Bioavailability Increases Renin Production in the Collecting Duct.

In the kidney, the stimulation of renin production by the collecting duct (CD-renin) contributes to the development of hypertension. The CD is a major nephron segment for the synthesis of nitric oxide (NO), and low NO bioavailability in the renal medulla is associated with hypertension. However, it is unknown whether NO regulates renin production in the CD. To test the hypothesis that low intrarenal NO levels stimulate the production of CD-renin, we first examined renin expression in the distal nephron segments of CD-eNOS deficient mice. In these mice, specific CD-renin immunoreactivity was increased compared to wild-type littermates; however, juxtaglomerular (JG) renin was not altered. To further assess the intracellular mechanisms involved, we then treated M-1 cells with either 1 mM L-NAME (L-arginine analog), an inhibitor of NO synthase activity, or 1 mM NONOate, a NO donor. Both treatments increased intracellular renin protein levels in M-1 cells. However, only the inhibition of NOS with L-NAME stimulated renin synthesis and secretion as reflected by the increase in Ren1C transcript and renin protein levels in the extracellular media, respectively. In addition, NONOate induced a fast mobilization of cGMP and intracellular renin accumulation. These response was partially prevented by guanylyl cyclase inhibition with ODQ (1H-[1,2,4] oxadiazolo[4,3-a]quinoxalin-1]. Accumulation of intracellular renin was blocked by protein kinase G (PKG) and protein kinase C (PKC) inhibitors. Our data indicate that low NO bioavailability increases CD-renin synthesis and secretion, which may contribute to the activation of intrarenal renin angiotensin system.

Phenology and growth of Fagus sylvatica and Quercus robur seedlings in response to temperature variation in the parental versus offspring generation.

Plants are known to respond to warming temperatures. Few studies, however, have included the temperature experienced by the parent plant in the experimental design, in spite of the importance of this factor for population dynamics. We investigated the phenological and growth responses of seedlings of two key temperate tree species (Fagus sylvatica and Quercus robur) to spatiotemporal temperature variation during the reproductive period (parental generation) and experimental warming of the offspring. To this end, we sampled oak and beech seedlings of different ages (1-5 years) from isolated mother trees and planted the seedlings in a common garden. Warming of the seedlings advanced bud burst in both species. In oak seedlings, higher temperatures experienced by mother trees during the reproductive period delayed bud burst in control conditions, but advanced bud burst in heated seedlings. In beech seedlings, bud burst timing advanced both with increasing temperatures during the reproductive period of the parents and with experimental warming of the seedlings. Relative diameter growth was enhanced in control oak seedlings but decreased with warming when the mother plant experienced higher temperatures during the reproductive period. Overall, oak displayed more plastic responses to temperatures than beech. Our results emphasise that temperature during the reproductive period can be a potential determinant of tree responses to climate change.

Publisher Correction: Protein-altering variants associated with body mass index implicate pathways that control energy intake and expenditure in obesity.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Protein-coding variants implicate novel genes related to lipid homeostasis contributing to body-fat distribution.

Body-fat distribution is a risk factor for adverse cardiovascular health consequences. We analyzed the association of body-fat distribution, assessed by waist-to-hip ratio adjusted for body mass index, with 228,985 predicted coding and splice site variants available on exome arrays in up to 344,369 individuals from five major ancestries (discovery) and 132,177 European-ancestry individuals (validation). We identified 15 common (minor allele frequency, MAF ≥5%) and nine low-frequency or rare (MAF <5%) coding novel variants. Pathway/gene set enrichment analyses identified lipid particle, adiponectin, abnormal white adipose tissue physiology and bone development and morphology as important contributors to fat distribution, while cross-trait associations highlight cardiometabolic traits. In functional follow-up analyses, specifically in Drosophila RNAi-knockdowns, we observed a significant increase in the total body triglyceride levels for two genes (DNAH10 and PLXND1). We implicate novel genes in fat distribution, stressing the importance of interrogating low-frequency and protein-coding variants.

Publisher Correction: Protein-altering variants associated with body mass index implicate pathways that control energy intake and expenditure in obesity.

In the published version of this paper, the name of author Emanuele Di Angelantonio was misspelled. This error has now been corrected in the HTML and PDF versions of the article.

Publisher Correction: Protein-altering variants associated with body mass index implicate pathways that control energy intake and expenditure in obesity.

In the version of this article originally published, one of the two authors with the name Wei Zhao was omitted from the author list and the affiliations for both authors were assigned to the single Wei Zhao in the author list. In addition, the ORCID for Wei Zhao (Department of Biostatistics and Epidemiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA) was incorrectly assigned to author Wei Zhou. The errors have been corrected in the HTML and PDF versions of the article.

Protein-altering variants associated with body mass index implicate pathways that control energy intake and expenditure in obesity.

Genome-wide association studies (GWAS) have identified >250 loci for body mass index (BMI), implicating pathways related to neuronal biology. Most GWAS loci represent clusters of common, noncoding variants from which pinpointing causal genes remains challenging. Here we combined data from 718,734 individuals to discover rare and low-frequency (minor allele frequency (MAF) < 5%) coding variants associated with BMI. We identified 14 coding variants in 13 genes, of which 8 variants were in genes (ZBTB7B, ACHE, RAPGEF3, RAB21, ZFHX3, ENTPD6, ZFR2 and ZNF169) newly implicated in human obesity, 2 variants were in genes (MC4R and KSR2) previously observed to be mutated in extreme obesity and 2 variants were in GIPR. The effect sizes of rare variants are ~10 times larger than those of common variants, with the largest effect observed in carriers of an MC4R mutation introducing a stop codon (p.Tyr35Ter, MAF = 0.01%), who weighed ~7 kg more than non-carriers. Pathway analyses based on the variants associated with BMI confirm enrichment of neuronal genes and provide new evidence for adipocyte and energy expenditure biology, widening the potential of genetically supported therapeutic targets in obesity.

Evidence for Prohypertensive, Proinflammatory Effect of Interleukin-10 During Chronic High Salt Intake in the Condition of Elevated Angiotensin II Level.

IL-10 (interleukin-10) has been suggested to play a protective role in angiotensin II (AngII)-induced cardiovascular disorders. This study examined the role of endogenous IL-10 in salt-sensitive hypertension and renal injury induced by AngII. Responses to chronic AngII (400 ng/min per kilogram body weight; osmotic minipump) infusion were evaluated in IL-10 gene knockout mice fed with either normal salt diet (0.3% NaCl) or high salt (HS; 4% NaCl) diet, and these responses were compared with those in wild-type mice. Normal salt diets or HS diets were given alone for the first 2 weeks and then with AngII treatment for an additional 2 weeks (n=6 in each group). Arterial pressure was continuously monitored by implanted radio-telemetry, and a 24-hour urine collection was performed by metabolic cages on the last day of the experimental period. Basal mean arterial pressure was lower in IL-10 gene knockout mice than in wild-type (98±3 versus 113±3 mm Hg) mice. Mean arterial pressure responses to normal salt/HS alone or to the AngII+normal salt treatment were similar in both strains. However, the increase in mean arterial pressure induced by the AngII+HS treatment was significantly lower in IL-10 gene knockout mice (15±5% versus 37±3%) compared with wild-type mice. Renal tissue endothelial nitric oxide synthase expression (≈3-folds) and urinary excretion of nitric oxide metabolites, nitrate/nitrite (1.2±0.1 versus 0.2±0.02 µmol/L/24 hours) were higher in IL-10 gene knockout mice compared with wild-type mice. These results indicate that an increase in nitric oxide production helps to mitigate salt-sensitive hypertension induced by AngII and suggest that a compensatory interaction between IL-10 and nitric oxide exists in modulating AngII-induced responses during HS intake.

Tumor necrosis factor-α, kidney function, and hypertension.

Hypertension is considered to be a low-grade inflammatory condition characterized by the presence of various proinflammatory cytokines. Tumor necrosis factor-α (TNF-α) is a constituent of the proinflammatory cytokines that is associated with salt-sensitive hypertension (SSH) and related renal injury. Elevated angiotensin II (ANG II) and other factors such as oxidative stress conditions promote TNF-α formation. Many recent studies have provided evidence that TNF-α exerts a direct renal action by regulating hemodynamic and excretory function in the kidney. The cytokine incites a strong natriuretic response and plays a part in regulation of the intrarenal renin-angiotensin system. The exact mechanistic role of TNF-α in the development of SSH is as yet poorly understood. While TNF-α antagonism has been shown to attenuate hypertensive responses in many hypertensive animal models, contrasting findings demonstrate that the direct systemic administration of TNF-α usually induces hypotensive as well as natriuretic responses, indicating a counterregulatory role of TNF-α in SSH. Differential activities of two cell surface receptors of TNF-α (receptor type 1 and type 2) may explain the contradictory functions of TNF-α in the setting of hypertension. This short review will evaluate ongoing research studies that investigate the action of TNF-α within the kidney and its role as an influential pathophysiological variable in the development of SSH and renal injury. This information may help to develop specific TNF-α receptor targeting as an effective treatment strategy in this clinical condition.

Drinking Water Salinity and Raised Blood Pressure: Evidence from a Cohort Study in Coastal Bangladesh.

BACKGROUND: Millions of coastal inhabitants in Southeast Asia have been experiencing increasing sodium concentrations in their drinking-water sources, likely partially due to climate change. High (dietary) sodium intake has convincingly been proven to increase risk of hypertension; it remains unknown, however, whether consumption of sodium in drinking water could have similar effects on health. OBJECTIVES: We present the results of a cohort study in which we assessed the effects of drinking-water sodium (DWS) on blood pressure (BP) in coastal populations in Bangladesh. METHODS: DWS, BP, and information on personal, lifestyle, and environmental factors were collected from 581 participants. We used generalized linear latent and mixed methods to model the effects of DWS on BP and assessed the associations between changes in DWS and BP when participants experienced changing sodium levels in water, switched from "conventional" ponds or tube wells to alternatives [managed aquifer recharge (MAR) and rainwater harvesting] that aimed to reduce sodium levels, or experienced a combination of these changes. RESULTS: DWS concentrations were highly associated with BP after adjustments for confounding factors. Furthermore, for each 100 mg/L reduction in sodium in drinking water, systolic/diastolic BP was lower on average by 0.95/0.57 mmHg, and odds of hypertension were lower by 14%. However, MAR did not consistently lower sodium levels. CONCLUSIONS: DWS is an important source of daily sodium intake in salinity-affected areas and is a risk factor for hypertension. Considering the likely increasing trend in coastal salinity, prompt action is required. Because MAR showed variable effects, alternative technologies for providing reliable, safe, low-sodium fresh water should be developed alongside improvements in MAR and evaluated in "real-life" salinity-affected settings. https://doi.org/10.1289/EHP659.

2-Methoxyestradiol Reduces Angiotensin II-Induced Hypertension and Renal Dysfunction in Ovariectomized Female and Intact Male Mice.

Cytochrome P450 1B1 protects against angiotensin II (Ang II)-induced hypertension and associated cardiovascular changes in female mice, most likely via production of 2-methoxyestradiol. This study was conducted to determine whether 2-methoxyestradiol ameliorates Ang II-induced hypertension, renal dysfunction, and end-organ damage in intact Cyp1b1-/-, ovariectomized female, and Cyp1b1+/+ male mice. Ang II or vehicle was infused for 2 weeks and administered concurrently with 2-methoxyestradiol. Mice were placed in metabolic cages on day 12 of Ang II infusion for urine collection for 24 hours. 2-Methoxyestradiol reduced Ang II-induced increases in systolic blood pressure, water consumption, urine output, and proteinuria in intact female Cyp1b1-/- and ovariectomized mice. 2-Methoxyestradiol also reduced Ang II-induced increase in blood pressure, water intake, urine output, and proteinuria in Cyp1b1+/+ male mice. Treatment with 2-methoxyestradiol attenuated Ang II-induced end-organ damage in intact Cyp1b1-/- and ovariectomized Cyp1b1+/+ and Cyp1b1-/- female mice and Cyp1b1+/+ male mice. 2-Methoxyestradiol mitigated Ang II-induced increase in urinary excretion of angiotensinogen in intact Cyp1b1-/- and ovariectomized Cyp1b1+/+ and Cyp1b1-/- female mice but not in Cyp1b1+/+ male mice. The G protein-coupled estrogen receptor 1 antagonist G-15 failed to alter Ang II-induced increases in blood pressure and renal function in Cyp1b1+/+ female mice. These data suggest that 2-methoxyestradiol reduces Ang II-induced hypertension and associated end-organ damage in intact Cyp1b1-/-, ovariectomized Cyp1b1+/+ and Cyp1b1-/- female mice, and Cyp1b1+/+ male mice independent of G protein-coupled estrogen receptor 1. Therefore, 2-methoxyestradiol could serve as a therapeutic agent for treating hypertension and associated pathogenesis in postmenopausal females, and in males.