Macrophage secretion of miR-106b-5p causes renin-dependent hypertension.

Myeloid cells are known mediators of hypertension, but their role in initiating renin-induced hypertension has not been studied. Vitamin D deficiency causes pro-inflammatory macrophage infiltration in metabolic tissues and is linked to renin-mediated hypertension. We tested the hypothesis that impaired vitamin D signaling in macrophages causes hypertension using conditional knockout of the myeloid vitamin D receptor in mice (KODMAC). These mice develop renin-dependent hypertension due to macrophage infiltration of the vasculature and direct activation of renal juxtaglomerular (JG) cell renin production. Induction of endoplasmic reticulum stress in knockout macrophages increases miR-106b-5p secretion, which stimulates JG cell renin production via repression of transcription factors E2f1 and Pde3b. Moreover, in wild-type recipient mice of KODMAC/miR106b-/- bone marrow, knockout of miR-106b-5p prevents the hypertension and JG cell renin production induced by KODMAC macrophages, suggesting myeloid-specific, miR-106b-5p-dependent effects. These findings confirm macrophage miR-106b-5p secretion from impaired vitamin D receptor signaling causes inflammation-induced hypertension.

Cold parenting is associated with cellular aging in offspring: A retrospective study.

BACKGROUND: Early life stress is a known risk factor for diseases and premature death. We tested whether parenting style impacts telomere length (TL), a cellular aging biomarker. METHODS: Information on parents' style of parenting was obtained from 199 participants in the Adventist Health Study-1 (AHS-1) who 27+ years later also enrolled in the AHS-2 where blood was collected for relative TL (rTL) assessment. RESULTS: Subjects describing their mothers' parenting style as cold had on average 25% smaller rTL compared to subjects not reporting a cold mother (1.89 vs 2.53). This association was greatest among those with less education, and those who stayed overweight/obese or put on weight during follow-up. CONCLUSIONS: These results support previous findings that early life stress may have health implications by promoting cellular aging, and expands these stressors to include cold parenting during an individuals' formative years. Higher education and normal weight seem to provide some resilience.

Ethnic Variations in Serum 25(OH)D Levels and Bone Ultrasound Attenuation Measurements in Blacks and Whites.

Vitamin D deficiency is more common in Blacks, yet Blacks have lower prevalence of bone fragility fractures or osteoporosis than Whites. Broadband ultrasound attenuation (BUA) has been used to explore the association between serum 25(OH)D levels and bone quality in White and non-white populations. We investigated serum 25(OH)D status with corresponding BUA measurements assessed cross sectionally in a cohort of 232 Blacks and 260 Whites, aged 30-95 years who were part of the calibration study of the large Adventist Health Study-2 (AHS-2). At the calibration clinics, calcaneal BUA was measured and blood drawn for serum 25(OH)D assessment. In multivariable analyses, BUA was negatively associated with age (ß-coefficient = -0.38; p < 0.0001) and positively associated with body mass index (BMI) (p (trend) < 0.0001) and positively, but non-significantly, associated with serum 25(OH)D levels. Also, as expected, females had lower BUA (ß-coefficient = -5.19; p < 0.05) and Blacks had higher BUA (ß-coefficient = 4.26; p < 0.05). Gender and race modified the relationship of serum 25(OH)D on BUA with a positive association in males (p (trend) ≤ 0.05), but no significant association in females after also controlling for menopausal status and hormone therapy. After also controlling for serum 25(OH)D levels, Black males had higher BUA than White men, but such differences were not found among the females. When stratifying on race, a positive association between serum 25(OH)D levels and BUA (p (trend) ≤ 0.05) was found in Blacks, but not among Whites. Further studies are needed to understand how racial/ethnic differences in serum 25(OH)D levels influence bone health.

The characterization of low-angle boundaries by EBSD.

A method of accurately measuring misorientations by electron backscatter diffraction (EBSD), which is an extension of that proposed by Wilkinson and based on the comparison of diffraction patterns, is described. The method has been applied to linescans, and found to improve the angular resolution by a factor of more than 30. The consequent improvement in determining misorientation axes is also analysed. Small changes of orientation very close to some low-angle boundaries were investigated and found to be artefacts of the analysis. Measurements of the area from which diffraction patterns are generated show this to be much larger than the effective spatial resolution of EBSD, and it is concluded that this may be a limiting factor in the use of EBSD for microstructural characterization.

Osteogenic protein-1 stimulates mRNA levels of BMP-6 and decreases mRNA levels of BMP-2 and -4 in human osteosarcoma cells.

Bone morphogenetic proteins (BMPs) are novel growth and differentiation factors that act on mesenchymal stem cells to initiate new bone formation in vivo and promote the growth and differentiation of cells in the osteoblastic lineage. In the present study, we examined the effects of recombinant human osteogenic protein-1 (also known as BMP-7) on the expression of related members of the BMP family using SaOS-2 and U2-OS, two human osteosarcoma cell strains. Evaluation of BMP-2, -4, and -6 mRNA expression indicates that OP-1 stimulated the mRNA levels of BMP-6 in both SaOS-2 cells (threefold) and U2-OS cells (fivefold) after 24 hours of treatment, while decreasing the mRNA levels of BMP-4 in SaOS-2 cells (80%) and BMP-2 and BMP-4 in U2-OS cells by 50% and 72%, respectively. BMP-2 mRNA expression, as examined by Northern blot analysis, was below detectable limits in SaOS-2 cultures. These results demonstrate that OP-1 modulates the mRNA expression of related members of the BMP family, suggesting a possible mode of action of OP-1 on the growth and differentiation of cells in the osteoblastic lineage in vitro.

Evidence that human bone cells in culture secrete insulin-like growth factor (IGF)-II and IGF binding protein-3 but not acid-labile subunit both under basal and regulated conditions.

Insulin-like growth factors (IGFs) are found in human circulation predominantly as part of a growth hormone (GH)-dependent complex of 125-150 kD, which is composed of three subunits: IGF-I or IGF-II, an acid stable IGF binding protein (IGFBP)-3, and an acid labile subunit (ALS). Although recent studies demonstrate that a number of cell types in culture secrete IGFs and IGFBP-3, very little is known with regard to the origin of circulating ALS. To test the hypothesis that human bone cells (HBCs), which produce abundant amounts of IGF-II and IGFBP-3, also produce ALS, we measured the IGF-I, IGF-II, IGFBP-3, and ALS levels using specific radioimmunoassays (RIAs) in the conditioned medium (CM) of untransformed normal HBCs and SaOS-2 osteosarcoma cells treated with various effectors (IGF-II, osteogenic protein-1 [OP-1, bone morphogenetic protein-7] and human GH) for 48 h. No detectable levels (< 3 ng/ml) of ALS were found in the CM of various HBC types under basal conditions. In contrast, CM collected from liver explants in culture contained significant amount of ALS prepared and assayed under identical conditions. The IGF-I level was also undetectable in the CM of various HBC types. In the IGF-II (3, 30 ng/ml)-treated HBC CM, the IGFBP-3 level was increased in a dose-dependent manner but neither IGF-I nor ALS could be detected. In the SaOS-2 cell culture, OP-1 (1, 100 ng/ml) increased both IGF-II and IGFBP-3 secretion but neither ALS nor IGF-I secretion. Treatment of HBCs with GH (1, 10, 100 ng/ml) had no significant effect on the secretion of either IGF-I, IGF-II, IGFBP-3, or ALS.(ABSTRACT TRUNCATED AT 250 WORDS)

Regulation of insulin-like growth factor system components by osteogenic protein-1 in human bone cells.

Bone morphogenetic proteins (BMPs) have the unique ability to convert mesenchymal cells into matrix-producing osteoblasts. To understand the mechanism(s) by which a BMP produces a multitude of effects on bone cells, we examined the effects of recombinant human osteogenic protein (OP)-1 (referred to as BMP-7) on the insulin-like growth factor (IGF) regulatory system, an important growth factor system in bone. After 48 h of treatment, OP-1 increased the level of IGF-II (3- and 2-fold, respectively, at 100 ng/ml) in the conditioned medium (CM) of SaOS-2 and TE85 human osteosarcoma cells with osteoblastic characteristics, whereas IGF-I levels were low to undetectable in the CM of either cell type. OP-1 treatment had no significant effect on the messenger RNA (mRNA) level for type 1 and type 2 IGF receptors. In TE85 and SaOS-2 cells, 100 ng/ml OP-1 increased the level of IGF binding protein (BP)-3 more than 10-fold, decreased the IGFBP-4 level by 50%, and increased the level of the 29-32.5 kDa IGFBP-5 3-fold in the CM as determined by analysis with Western ligand blot, Western immunoblot, and RIA. The effect of OP-1 on IGFBP production was time and dose dependent. The OP-1 induced changes in the levels of IGFBPs were associated with decreased IGFBP-3 and -5 protease activity (29% and 71%, respectively) and proportional changes in IGFBP mRNA levels. OP-1 increased the level of IGFBP-3 mRNA (2- and 10-fold, respectively, after 4 and 24 h of treatment at 100 ng/ml) and of IGFBP-5 mRNA (more than 5-fold after 24 h of treatment) but decreased the level of IGFBP-4 mRNA (> 50% after 24 h at 100 ng/ml). OP-1 treatment had no effect on IGFBP-4 protease activity. These results collectively demonstrate that OP-1 can act locally by modulating the IGF regulatory system, suggesting that the mitogenic/differentiative effect of OP-1 on human bone cells may in part be mediated via IGF-II by increasing its secretion, and by regulating the balance between the stimulatory (e.g. IGFBP-5) and inhibitory (e.g. IGFBP-4) classes of IGFBPs both at the level of production (mRNA) and at the level of degradation but not by up-regulating the IGF receptor.

Intravenous theophylline-induced excretion of calcium, magnesium and sodium in patients with recurrent asthmatic attacks.

Hypomagnesaemia in a woman treated with theophylline and albuterol because of recurrent asthmatic attacks prompted us to explore the effects of these drugs on the metabolism of magnesium, calcium, sodium and phosphate in such patients. Theophylline given intravenously to 10 females with recurrent asthmatic attacks increased total mean urinary excretion (mean +/- SEM, mmol 5 h-1) of Mg from 0.54 +/- 0.07 to 0.86 +/- 0.10; of Ca from 0.89 +/- 0.18 to 1.45 +/- 0.26; of Na from 22.9 +/- 7.5 to 49.4 +/- 9.5. Theophylline i.v. and an inhaled beta 2-agonist (albuterol) both increased the normal morning-till-noon serum concentration difference (mean +/- SEM, mmol l-1) in PO4 (from -0.13 +/- 0.04 to - 0.23 +/- 0.03 and -0.23 +/- 0.04, respectively) and reduced the normal increase in serum-K (from 0.25 +/- 0.07 to 0.06 +/- 0.08 and -0.13 +/- 0.09, respectively). Disproportional changes in serum and urinary levels of magnesium and calcium by theophylline i.v. is suggestive of Mg depletion of intracellular stores and a negative calcium balance. Theophylline, therefore, may exert adverse effects on the metabolism and urinary excretion of calcium and magnesium in subjects with recurrent asthmatic attacks.

Osteogenic protein-1 stimulates proliferation and differentiation of human bone cells in vitro.

The effect of recombinant human osteogenic protein-1 (OP-1) on proliferation and alkaline phosphatase (ALP) activity was studied using human bone cells in culture. TE85, osteosarcoma cells with osteoblastic characteristics and normal bone cells derived from mandible (HBM) were used. OP-1 stimulated 3H-thymidine incorporation in a dose dependent manner in TE85 (5-fold over vehicle control at 3-10 ng/ml) and HBM cells (1.8-fold at 100 ng/ml). In TE85 cells, OP-1 also increased cell number (2.4-fold over vehicle control at 3 ng/ml). OP-1 stimulated ALP activity in TE85 cells (4-fold over vehicle control at 30 ng/ml), but moderately inhibited ALP activity in HBM cells (to 67% of vehicle control at 100 ng/ml). Because 1,25(OH)2D3 has been shown to increase ALP activity in many cell types, we also studied if 1,25(OH)2D3 modulates the effects of OP-1 on ALP activity. In the presence of 10(-8) M 1,25(OH)2D3, a biphasic response occurred in TE85 and HBM cells with stimulation of ALP activity at low dose of OP-1 and inhibition at high dose. Thus, the effect of OP-1 on ALP activity appeared to be modulated by 1,25(OH)2D3. Our results suggest that OP-1 could be an important regulator of osteoblast proliferation and differentiation.

The Tromsø Survey: the Family Intervention study--the effect of intervention on some coronary risk factors and dietary habits, a 6-year follow-up.

While most intervention studies on coronary heart disease have focused on the high-risk person only, the present study used the family as the unit of intervention. In the study 1373 high-risk men, ages 30-54 years, were identified on the basis of high total cholesterol (TC) and/or low relative high-density lipoprotein cholesterol (HDL-C) (HDL-C/TC) following the 1979/1980 survey in Tromsø. The men and their families were randomly allocated to a control or intervention condition. The intervention families were given advice on diet, smoking, and exercise. At rescreening in 1986/1987, significantly lower risk factor levels were found in both the intervention men and their spouses compared with those in the control group. For children, the differences were small and mostly nonsignificant. Men, spouses, and children in the intervention group reported more favorable dietary habits than those in the control group. No differences were found in smoking or leisure time physical activity.

Cardiovascular risk factor levels in ethnic Hawaiians.

We report a cardiovascular risk factor survey of "native" Hawaiians 20-59 years old (70 percent, or 257), living on the Hawaiian Homestead lands on the island of Molokai, Hawaii. More than 60 percent of both sexes were overweight. Among males, 42 percent were smokers. The percent of the population with systolic blood pressure greater than 140 mm Hg or a diastolic pressure greater than 90 mm Hg or taking hypertensive medications was 14 percent of those ages 20-39 and 36 percent of those ages 40-59. The percent with serum cholesterol greater than or equal to 6.2 mmol/L ranged from 8 percent of those 20-29 years old to 46 percent in those 50-59 years old. Two percent of those ages 20-29 had a history of diabetes, or 2 + or greater glycosuria by dipstick, as did 23 percent of those ages 50-59. The majority of the known diabetics exhibited glycosuria and elevated glycohemoglobin levels, indicating poor control. Hypertension, although usually known to the participant, was frequently uncontrolled. From these data, it appears that among this group of Hawaiians major risk factors for cardiovascular disease were frequent, while at the same time the levels of awareness and/or control for most of these factors were low.

Wives of coronary high-risk men--are they also at higher risk? The Tromsø Heart Study.

Blood lipids, blood pressure, body mass index (BMI), smoking, dietary and exercise habits were studied in 911 wives of men with high risk for coronary heart disease (CHD). Following the 1979/80 Tromsø Survey, 1373 men, aged 30-54 years, were identified as having high risk for CHD (HDL-cholesterol/total cholesterol less than or equal to 17.6% and/or total cholesterol greater than or equal to 7.86 mmol l-1). Of the 1373 men, 911 individuals had wives who also attended the screening. These wives were compared to age-matched, married women in the general population. A significantly higher total cholesterol level (5.98 mmol l-1 vs. 5.78 mmol l-1), lower HDL-cholesterol/total cholesterol (30.01% vs. 31.58%), higher BMI and higher coronary risk score (4.55 vs. 3.82) was found among the wives of the high-risk men. Furthermore, a higher proportion of these individuals were daily cigarette smokers (47.3% vs. 42.1%), and had received fewer years of education. They also had more dietary habits associated with increased risk of CHD than other married women in the general population. Our findings support the hypothesis that members of the same household as a person with increased risk for CHD also have increased risk. This is most probably due to shared lifestyle.

The Tromsø Heart Study: family approach to intervention on CHD. Feasibility of risk factor reduction in high-risk persons--project description.

Intervention on high risk persons for CHD has shown varying results depending on the effectiveness of the intervention. Most studies have concentrated on the high-risk person only. The present study focuses on the high-risk family as an entity. 1,373 high-risk men, 30-55 years, were identified on the basis of high total cholesterol and/or low relative HDL (HDL-cholesterol/tot. cholesterol) in the Tromsø II screening in 1979/80, and randomly allocated to intervention or control group. The 673 men in the intervention group and their families, were offered advice to reduce their risk during two home visits and later by quarterly newsletters. Follow-up blood samples drawn 1.5 years following the home-visit, show a small reduction in total cholesterol and an increase in the ratio of HDL cholesterol/total cholesterol. Both the intervention and control group were invited to the examination in connection with the Tromsø III screening in 1986/87 and are being followed for 10 years on cardiovascular morbidity and mortality.

Predictive value of resting electrocardiograms for 12-year incidence of stroke in the Honolulu Heart Program.

The importance of electrocardiographic (ECG) abnormalities at baseline examination for subsequent risk of stroke was analyzed in a 12-year follow-up of 7,560 men in the Honolulu Heart Program, aged 45-68 years, who were free of coronary heart disease and stroke at baseline. Age-adjusted univariate analysis showed that men with major ST depression, left ventricular strain, left ventricular hypertrophy, major T wave inversion, and overall major ECG abnormalities had considerably higher (2.5-5.4 times) incidence rates of both thromboembolic and hemorrhagic stroke than those with normal baseline ECG. When blood pressure, age, cigarette smoking, alcohol consumption, fat intake, serum glucose concentration, serum uric acid concentration, years of education, and years lived in Japan were taken into consideration through multivariate analysis, the ECG abnormalities retained a significant relation with stroke. Our study demonstrates that resting ECG abnormalities are independent predictors of both thromboembolic and hemorrhagic stroke.

The predictive value of resting electrocardiograms for 12-year incidence of coronary heart disease in the Honolulu Heart Program.

The predictive value of electrocardiographic (ECG) abnormalities at baseline for subsequent risk of fatal and total coronary heart disease (CHD) was analyzed in a 12-year follow-up of 7682 men in the Honolulu Heart Program aged 45-68 who were free of CHD at baseline. Univariate analysis showed that men with major or minor ECG abnormalities, ST depression, high R wave, T-wave inversion, left ventricular hypertrophy or strain and premature ventricular contractions had considerably higher (2-10 fold) CHD incidence rates than those with normal ECG. When blood pressure, cigarette smoking, body mass index, alcohol use, physical activity, serum glucose, serum cholesterol, serum uric acid, age and years lived in Japan were taken into consideration through multivariate analysis, the ECG abnormalities retained significant associations with fatal and total CHD. This study demonstrated that resting ECG abnormalities were independent predictors of both total and fatal CHD.

The Tromsø Heart Study: comparison of information from a short food frequency questionnaire with a dietary history survey.

In a group of 528 men, 30-54 years old, answers to various questions about dietary habits given in a questionnaire were compared to corresponding information given in a dietary history interview two years later. High concordance was found between the two methods for questions concerning types of foods most commonly used. For most food items, the mean intake according to the dietary recall corresponds well with intake reported in the questionnaire. For food items used every day in easily recorded units (slices of bread, cups of coffee, glasses of milk), the frequency questionnaire can be used to rank individuals according to consumption. For other food items, the concordance is less satisfactory.