| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
(Hypertension. 1997;30:134-139.)
© 1997 American Heart Association, Inc.
Articles |
Increased Transforming Growth Factor-ß Production and Gene Expression by Peripheral Blood Monocytes of Hypertensive Patients
From the Department of Internal Medicine (E.P., C. Di F., G.B., M.D.G., F.C.) and Institutes of Human Pathology and Social Medicine (G.M., G.C.) and Immunology (M.R.), University of Chieti (Italy), Medical School.
Correspondence to Dr Ettore Porreca, Laboratorio di Fisiopatologia Medica Centro Servizi Biomedici, Via dei Vestini, Università G. D'Annunzio, 66013 Chieti, Italy.
 |
Abstract |
|---|
 Top Abstract IntroductionMethodsResultsDiscussionReferences |
|---|
Abstract Cultured human peripheral blood monocytes are known to secrete and express transforming growth factor-ß (TGF-ß), a multifunctional cytokine that can be involved in myocardial and vascular remodeling. In addition, monocytes/macrophages have been demonstrated to be colocalized with fibrosis of hypertrophied heart and in the vascular wall of hypertensive vessels. In this study, we tested TGF-ß production and mRNA expression in peripheral blood monocytes from hypertensive patients with myocardial hypertrophy and increased carotid myointimal thickness with respect to healthy normotensive control subjects. We found an increased TGF-ß activity in the conditioned medium of monocytes from hypertensive patients compared with control subjects as evaluated by inhibition of [3H]thymidine incorporation by mink lung epithelial cells (-83% and -18% in hypertensive and normotensive subjects; P<.001). Western blot analysis confirmed a significant difference in the amount of TGF-ß protein secreted in the conditioned medium of hypertensive patients compared with that of normotensive subjects. Finally, we also observed a 4.2- and 5.5-fold increase in the amount of TGF-ß1 and TGF-ß2 transcripts, respectively. Our results indicate an upregulation of the TGF-ß system in the peripheral blood monocytes of hypertensive patients with cardiovascular structural changes, suggesting a possible role of TGF-ß monocyte production in hypertensive disease.
Key Words: transforming growth factors • monocytes • heart hypertrophy • remodeling
|
Introduction |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Transforming growth factor-ß (TGF-ß) is a multifunctional cytokine that regulates many cellular functions, including cell growth and differentiation,1 2 modulation of extracellular matrix synthesis, and tissue repair,3 4 5 and may play an important role in regulating inflammation and immune responses.6 7 TGF-ß may also play a significant role in the vascular remodeling process8 and myocardial hypertrophy9 brought on by hypertension. TGF-ß1 mRNA has been found to be increased in the aorta of deoxycorticosterone-salt hypertensive rats compared with normotensive rats,10 and vascular smooth muscle cells of spontaneously hypertensive rats show an altered responsiveness to TGF-ß1 as well as autocrine TGF-ß expression.11 In vivo data indicate that infusion of TGF-ß1 or transfection of TGF-ß1 cDNA12 into injured arteries strongly accelerates lesion formation by increasing cellularity and extracellular matrix accumulation.
Myocardial fibrosis associated with hypertensive cardiac hypertrophy13 has been related to chronic elevations in circulating and/or local concentrations of stimulatory hormones.14 In this context, TGF-ß1, fibronectin, and collagen mRNA are induced in the thoracic-banded hypertrophied rat myocardium,15 and TGF-ß1 transcripts are increased in the myocyte fraction obtained from experimental myocardial hypertrophy induced by aortic constriction or after subcutaneous infusion of norepinephrine.16
In the present study, we evaluate the production and mRNA gene expression of TGF-ß in in vitro cultures of peripheral blood monocytes from hypertensive patients with cardiac hypertrophy and myointimal thickening with respect to healthy normotensive subjects. We used circulating leukocytic cells in accordance with the systemic nature of the structural remodeling process,14 since inflammatory cells are potential sources of TGF-ß in vivo,17 18 19 as well as monocytes that have been found in the subendothelium of spontaneously hypertensive rats,20 in myocardial perivascular sites, and colocalized with myocardial fibrosis in hypertrophied hearts.21 22 Finally, hypertension may enhance the responsiveness of endothelium to factors that promote monocyte adhesion,23 and atherosclerotic disease associated with hypertension is in turn characterized by an inflammofibroproliferative response in the vascular wall.24 Our results show an increased capacity of monocytes of hypertensive patients to produce active TGF-ß. This increased secretion was due to an unstimulated increase in mRNA expression of TGF-ß1 and TGF-ß2. These findings suggest that monocyte synthesis of TGF-ß may play a role in cardiovascular remodeling of hypertensive disease.
|
Methods |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Subjects
We studied 22 hypertensive patients (8 men, 14 women; mean age, 54±9 years) admitted to our Department of Internal Medicine with a history of previously untreated mild to moderate essential hypertension. All patients had appropriate clinical and laboratory evaluations to exclude secondary hypertension.25 Noncardiovascular conditions associated with a possible pathogenetic role for TGF-ß (ie, malignancy, acute and chronic liver disease, and connective tissue disease) were excluded after complete medical and laboratory examinations. The control subjects consisted of 22 consecutive normotensive blood donors (8 men, 14 women; mean age, 51±8 years) without acute or chronic illness; none of them reported any symptoms related to the cardiovascular system.
The general biochemical evaluation included plasma glucose concentration; serum lipid profile; and measurement of serum potassium, serum and urinary creatinine, and inflammatory reactants (erythrocyte sedimentation rate, C-reactive protein, white blood cells). Biochemical parameters were measured by routine laboratory methods. The study was approved by the Ethics Review Committee of the University of Chieti; all participants gave written informed consent.
Echocardiography and Carotid
Ultrasonography
All subjects underwent M-mode, two-dimensional, and Doppler
ultrasound performed with an ultrasound imaging system (Hewlett-Packard
77030A) equipped with a 2.5-MHz transducer. Left
ventricular (LV) dimensions were obtained from
two-dimensionally guided M-mode tracings according to the
recommendation of the American Society of
Echocardiography.26 LV mass was
calculated according to Penn Convention recommendations.27
LV mass was indexed by body surface area (LV mass index). The relative
wall thickness was measured at end diastole as the ratio of
2xPosterior Wall Thickness/LV Internal Dimensions.
Arterial wall thickness was evaluated by carotid ultrasonography performed with a 7.5-MHz transducer.28 Intima-media thickness was measured in both right and left common carotid arteries at least 1 cm below the carotid bifurcation. The intima-media thickness was defined as the distance from the leading edge of the lumen-intima interface of the far wall to the leading edge of the media-adventitia interface of the far wall. Measurements were taken at end diastole by electrocardiographic triggering. The mean of six measurements was used to derive an estimate of the overall intima-media thickness of the common carotid arteries. A repeat scan was made after 1 week to determine the reproducibility of the measurements. The coefficient of variation was 6.7%.
Isolation of Blood Monocytes and Cell Cultures
Peripheral heparinized blood was diluted 1:1 with
normal saline, and mononuclear cells were separated by a Ficoll-Hypaque
gradient (Pharmacia LKB Biotechnology Inc).29 30
Mononuclear cells were recovered at the interface, and
peripheral blood mononuclear cells were rendered
plasma-free and platelet-poor by washing three times with
HEPES-buffered (10 mmol/L) Hanks' balanced salt solution and
resuspended at the desired concentration in RPMI-1640 medium (GIBCO)
supplemented with 0.3 mg/mL L-glutamine, 80 µg/mL
gentamicin, and 5% heat-inactivated endotoxin-free fetal
calf serum. Aliquots (2.5-mL) were seeded into Petri dishes and
incubated at 37°C in a 5% CO2–humidified atmosphere for
60 minutes. After that time, the supernatants, which contained
nonadherent cells, were discarded, and the remaining adherent monocytes
(95% purity determined by fluorescein
isothiocyanate–labeled OKM5 staining) were cultured in RPMI-1640
medium supplemented with 0.3 mg/mL L-glutamine, 80 µg/mL
gentamicin, and 1% endotoxin-free fetal calf serum at a density of
3x106/mL in T75 flasks (Nunc). All cell cultures were
maintained at 37°C in a controlled humidified 95% air/5%
CO2 atmosphere. Viability of the cultured cells was
determined by trypan blue exclusion. The culture medium contained less
than 10 pg/mL of lipopolysaccharides, as determined by the
Limulus amebocyte lysate test.
Preparation of Monocyte Conditioned Medium and Mink Lung Epithelial
Cell DNA Synthesis Bioassay for Active TGF-ß
Conditioned medium (CM) from equal cell numbers of cultured
monocytes of patients and healthy control subjects was harvested after
24 hours and stored at -20°C before assay. As most TGF-ß is
secreted in a latent form that is biologically inactive,31
the monocyte CM was activated by acidification before the assay
using a standard protocol to examine the production of active
TGF-ß. Briefly, CM was acidified with 10% (vol/vol) of 1 mol/L
hydrochloric acid and incubated at room temperature for 60 minutes. An
equal amount of 1 mol/L sodium hydroxide solution was added for
neutralization, and the CM was added to the assay plates. TGF-ß
activity by monocytes was examined by a bioassay sensitive to
TGF-ß1 -ß2, and
-ß3.32 CCL-64 mink lung epithelial cells
(American Type Culture Collection) were plated in Dulbecco's modified
Eagle's medium plus 10% fetal calf serum at a density of
8x103 cells per 0.2 mL in 96-well plastic plates. After 20
hours, the medium was replaced, and aliquots of the test samples were
added in quadruplicate to monolayers. After 22 hours, DNA synthesis was
determined by pulsing for 4 hours with 0.5 µCi of
[3H]thymidine (2 µCi/mL, Amersham International plc).
The amount of radioactivity in the cells exposed to the test samples
was determined with a liquid scintillation counter (Packard
Instruments). A standard curve was constructed with increasing
concentrations of purified platelet human TGF-ß1 (R&D
System) in each experiment. In preliminary experiments, we tested
TGF-ß activity in the acidified CM of monocyte cultures of control
subjects and hypertensive patients at different dilutions. About 50%
inhibition was observed at dilutions of 1:4 and 1:16 CM for control
subjects and hypertensive patients, respectively. To test all samples,
we used a dilution of 1:8, which accurately detected TGF-ß activity
in the linear portion of its standard curve. On the basis of the
standard curve, TGF-ß levels were calculated by multiplying the
measured TGF-ß concentrations by the dilution factor and were
expressed as nanograms per milliliter.
For determination of the specificity of the inhibitory response, a purified IgG fraction of rabbit polyclonal neutralizing anti–TGF-ß (Pan-specific TGF-ß neutralizing antibody, R&D System) was added to the CM 1 hour before its addition to the mink lung epithelial cells.
Western Blot Analysis
CM of cultured mononuclear cells was collected after 24 hours,
centrifuged at 3500 rpm at 4°C, and concentrated with
centrifuge concentrators (Centripor; molecular weight cutoff,
10 000 D; Spectrum Microfuge). Aliquots (20 µL) of concentrated and
desalted supernatants were resuspended in 10 µL sample buffer
(50 mmol/L Tris-HCl [pH 6.8], 2% sodium dodecyl
sulfate, 0.1% bromophenol blue, 10% glycerol) and subjected to sodium
dodecyl sulfate–polyacrylamide gel electrophoresis on
a 15% acrylamide gel for 60 minutes at 180V using a
minigel vertical apparatus (Bio-Rad Laboratories, SrL).
Some samples were reduced with sample buffer plus 5%
ß-mercaptoethanol. For reference purposes, 10 ng human platelet
purified TGF-ß1 (R&D System) was coelectrophoresed in a
separate lane. Size-separated proteins were blotted onto Hybond ECL
membrane (Amersham International), saturated with a solution of 5%
nonfat milk in phosphate-buffered saline/0.1% Tween-20 (PBS/Tween-20),
and incubated for 60 minutes with rabbit polyclonal IgG antibody
directed against human TGF-ß (1:2000) (R&D System). The filters were
washed three times in PBS/Tween-20 and incubated for 60 minutes with
rabbit horseradish peroxidase–labeled conjugated anti-rabbit IgG
(1:3000) for 60 minutes at room temperature. The immune complex was
visualized with the ECL Western blot detection system (Amersham
International).
RNA Extraction and Northern Blot Analysis
RNA was purified from cultured adherent monocytes by a
modification of the guanidine hydrochloride extraction
method.33 Total RNA (5 µg) was fractionated on a 1%
formaldehyde agarose gel, transferred to nylon membranes (Hybond N,
Amersham International), and hybridized following the standard
procedure. Gel-purified fragments of DNA random primed with
32P (2x108 cpm/µg) were used for
hybridization. The probe used was human TGF-ß cDNA, 1.3-kb fragment,
which recognizes TGF-ß1 and TGF-ß2 isoforms
(a kind gift of Dr M.L. McGeidy, Laboratory of Tumor Immunology and
Biology, NIC, Bethesda, Md).
The sizes of the transcripts were indicated as relative to 18S and 28S rRNA, which were assumed to be 1.8 and 5.4 kb, respectively. Autoradiograms were prepared using exposure times of 18 hours. To compare the TGF-ß mRNA signals, we used a cDNA probe for GAPDH (American Type Culture Collection). A densitometer (Ultrascan XL, Pharmacia LKB) was used for normalization. The autoradiograms were scanned and peak areas measured for relative mRNA levels (TGF-ß mRNA/GAPDH) in the samples tested. Values were stored in a spreadsheet software program that produced a graphic representation of the signals.
Statistical Analysis
All data are reported as mean±SD. The significance of
differences between the two groups was evaluated by the Mann-Whitney
U test or Student's t test for unpaired data.
One-way ANOVA and the Student-Newman-Keuls test were performed when
appropriate. A value of P<.05 was considered statistically
significant.
|
Results |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Clinical, Biochemical, Echocardiographic, and Carotid Ultrasonographic Characteristics
The Table
shows clinical, biochemical, and
ultrasonographic findings in the control normotensive subjects and
hypertensive patients. There were no significant differences between
groups in sex, age, smoking habits, serum lipids values, platelets,
and white blood cell numbers. Biochemical parameters of
inflammatory reaction did not change in either group. By design, the
hypertensive patients had significantly higher systolic
(160±12 versus 124±10 mm Hg, P<.0001),
diastolic (102±6 versus 72±9, P<.0001), and
mean arterial (121±7 versus 89±8 mm Hg,
P<.0001) blood pressures than their normotensive
counterparts. LV mass index increase significantly in the hypertensive
patients with respect to control subjects (130±36 versus 104±31
g/m2, P<.05), as did relative wall thickness
(48.7±7.6 versus 40±10, P<.005) and intima-media
thickness (0.97±0.13 versus 0.69±0.11 mm,
P<.0001).
|
Detection of Biological Activity and TGF-ß Protein in Medium From
Monocyte Cultures
Mink Lung Epithelial Cell DNA Synthesis
It is well known that isolated monocytes secrete TGF-ß in a
latent form that can be activated by acidification. According
to the study by Assoian et al,18 the activity of untreated
CM from our monocyte cultures was very low, as tested in the mink lung
DNA synthesis assay. Thus, in all 44 subjects, we examined the
production of active TGF-ß in the monocyte CM after
acidification before the bioassay using a standard protocol, as
described in "Methods." Fig 1 (top) shows that the
mink lung cells responded to purified TGF-ß1 with a
dose-dependent decrease in DNA synthesis, expressed as a percentage of
basal [3H]thymidine incorporation (5400 cpm). CM from
monocyte cultures from hypertensive patients and control subjects was
added to parallel cultures of mink lung cells, and the effects on DNA
were synthesis examined. CM of monocyte cultures from hypertensive
patients and control subjects inhibited mink lung epithelial cell DNA
synthesis to 17±7% and 82±30% of control values, respectively
(P<.001) (Fig 1, top, open circles). Using the standard
curve generated with purified TGF-ß1, these levels of
inhibition equated to 1.76±0.2 ng/mL per 106 cells of
TGF-ß activity in the medium of normotensive subjects, which
increased 2.7-fold in the medium of hypertensive patients (4.8±0.5
ng/mL per 106 cells, P<.001).
|
) expressed as
percentage of basal [3H]thymidine incorporation (5400
cpm). CM from monocyte cultures was added to parallel cultures of mink
lung cells, and the effects on DNA synthesis were examined (top,
). Comparison with the standard curve and multiplication by the
dilution factor (1:8) yielded TGF-ß concentration in CM of monocyte
cultures. Open circles represent mean values obtained from
multiple sample (n=22 patients for each group). For each sample, four
measures of [3H]thymidine incorporation were made.
Bottom, Effect of a pan-specific TGF-ß neutralizing antibody (Ab-anti
TGFß) (0.1, 0.5, 5, and 10 µg/mL) on [3H]thymidine
uptake by mink lung cells induced by CM (c.m. in the figure) of
monocyte cultures from hypertensive patients. The antibody was added to
CM 1 hour before its addition to mink lung epithelial cells. Results
are mean±SD from four hypertensive patients. Data represent
the average of quadruplicate determinations. Nonspecific rabbit IgG (10
µg/mL) was used for comparison. NS indicates nonsignificant versus
control (C) by the Student-Newman-Keuls test.
The growth-inhibitory activity in the CM of monocytes was
due to TGF-ß because pretreatment of CM with a neutralizing antibody
abolished the growth-inhibitory effect. Fig 1
, bottom,
shows that the inhibitory effect on
[3H]thymidine incorporation observed for a sample from a
hypertensive patient was abolished after coincubation with 10 µg/mL
of neutralizing anti–TGF-ß. The same neutralizing activity was
observed for the small inhibition on [3H]thymidine
incorporation observed in control CM (data not shown).
Western Blot Analysis
To verify whether the increase in TGF-ß activity was due to an
increase of the protein growth factor secreted in the medium, we
performed Western blot analysis in six subjects per group. CM
secreted by human peripheral blood monocytes from control
subjects and hypertensive patients was collected after 24 hours of
culture, concentrated, and subjected to Western blot analysis.
With the use of a rabbit antibody prepared against several isoforms of
TGF-ß, a 25-kD peptide was detected in the medium of both
normotensive subjects and hypertensive patients (Fig 2).
According to the disulfide-linked 12.5-kD peptide
structure,2 reduction with ß-mercaptoethanol resulted in
a shift to a 12.5-kD form in the monocyte TGF-ß. An increase in the
amount of immunoreactive peptide was seen in the medium of monocyte
cultures from hypertensive patients compared to that from normotensive
subjects. Densitometric analysis of the Western blot showed a
fourfold increase in the amount of TGF-ß secreted by cultured
monocytes from hypertensive patients with respect to control subjects
(P<.001).
|
TGF-ß mRNA Expression
To study whether the increase in TGF-ß production in
hypertensive patients was due to a transcriptional upregulation, we
carried out a Northern blot experiment using a cDNA probe that
recognizes both TGF-ß1 and TGF-ß2 mRNA
sequences. Since previous studies showed similar levels of
TGF-ß1 transcripts in both activated and
nonactivated monocytes,18 19 we tested
"constitutive" mRNA expression in our peripheral
blood monocytes. Fig 3 shows
representative Northern blot analysis of TGF-ß mRNA
of three hypertensive patients and three control subjects after 24
hours of incubation. TGF-ß mRNA levels were calculated in relation to
GAPDH levels in the same sample. A 2.4- and 6.5-kb mRNA for
TGF-ß1 and TGF-ß2 were present in
control subjects and hypertensive patients. A significant increased
amount of TGF-ß1 and TGF-ß2 transcript was
detected in the monocytes of hypertensive patients compared with those
of control subjects. TGF-ß1 and TGF-ß2 mRNA
contents in 15 patients and 15 normotensive control subjects were
normalized to that of GAPDH mRNA as described in "Methods" and
expressed as mean densitometric absorbance units (Fig 4). The values of the densitometric ratios
(TGF-ß1 and TGF-ß2/GAPDH mRNA) showed mean
increases of 4.2- and 5.5-fold, respectively, in cultured monocytes of
hypertensive patients compared with control subjects.
|
|
|
Discussion |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
We designed the current study to examine TGF-ß production and its mRNA expression by human monocytes of hypertensive patients with cardiovascular structural changes. We tested a basic aspect of monocyte behavior in ex vivo cultures of peripheral blood monocytes of hypertensive patients with concentric hypertrophy and myointimal thickening with respect to healthy subjects. In CM from nonstimulated monocytes (24-hour collection), we first evaluated the biological activity of TGF-ß by bioassay on mink lung epithelial cells. A significantly greater inhibitory effect in [3H]thymidine incorporation of mink lung cells was observed in the CM of monocytes from hypertensive patients than in those from control subjects. To verify whether the increase in TGF-ß activity was due to transcriptional regulation, we performed Northern blot analysis for TGF-ß mRNA expression.
We found a significant mean increase of TGF-ß1 (4.2-fold) and TGF-ß2 (5.5-fold) transcripts in monocyte cultures of hypertensive patients with respect to normotensive control cultures after 24 hours of incubation. Western blot analysis performed on the CM from monocyte cultures further confirmed the previously observed differences in the mRNA amount and biological activity, showing a significant increase in the corresponding protein in cultures of monocytes from hypertensive patients. Thus, a spontaneous increase in TGF-ß production by mononuclear cells of hypertensive patients correlated with and enhanced expression of TGF-ß mRNA.
Our results support the hypothesis that monocytes/macrophages possibly recruited into the cardiovascular tissue may represent a significant source of TGF-ß. Thus, even though TGF-ß induction in hypertrophied myocardium after pressure overload has been demonstrated to be associated with the myocyte fraction,19 colocalization of fibroblastic activity with lymphocytes and macrophage infiltration in the hypertrophied myocardium suggest the possibility of a leukocytic origin of myocardial TGF-ß, which may play a role in the process of myocardial fibrosis.
Furthermore, upregulation of the TGF-ß system in monocytes of hypertensive patients supports the view of cellular (monocyte) involvement in the pathogenesis of atherosclerotic lesions associated with hypertension.34 35 In this setting, the observed association between LV hypertrophy and carotid atherosclerosis has been demonstrated to be independent of hypertensive blood pressure values,35 and attempts to reduce cardiovascular complications due to atherosclerosis with antihypertensive treatment have not always been successful.34 The significant increase in monocyte TGF-ß2 mRNA observed in our study agrees with other studies showing the involvement of TGF-ß2 in vascular remodeling and in vivo fibrosis36 37 38 and further supports a role for the TGF-ß system in the pathophysiology of vascular matrix remodeling.8 We did not evaluate the mechanisms involved in the increased expression of TGF-ß mRNA levels in the monocytes of hypertensive patients. However, induction of TGF-ß mRNA by autocrine or paracrine TGF-ß has been demonstrated in fibroblasts and vascular smooth muscle cells39 ; also, the growth-promoting effect of angiotensin has been shown to occur when angiotensin activates autocrine and paracrine growth factors, including TGF-ß.40 41 In this context, in the present study, we did not test the relationship between TGF-ß production/expression and the cardiovascular renin-angiotensin system, which also plays a significant role in cardiac and vascular hypertrophy and remodeling.42 However, interestingly, converting enzyme inhibitors prevent the increased monocyte/macrophage traffic throughout the arterial wall as well as myocardial fibrosis23 ; angiotensin II type 1 receptor antagonists inhibit the gene expression of TGF-ß1 and extracellular matrix in cardiac and vascular tissue of hypertensive rats43 ; and angiotensin II receptors have been demonstrated in human monocytes.44 Thus, a possible relationship between the renin-angiotensin and TGF-ß systems, possibly at the monocyte level, cannot be excluded.
In conclusion, our findings indicate that the source of TGF-ß in cardiovascular tissues during hypertensive disease may be of macrophage/monocytic origin. The increased TGF-ß production associated with increased mRNA expression observed in hypertensive patients demonstrates an upregulation of the TGF-ß system and also supports the possibilities that macrophage/monocytic cells infiltrate hypertrophic myocardium or that the vascular wall plays a significant role in the cardiovascular remodeling process.
|
Acknowledgments |
|---|
This work was partially supported by the ACRO Project of the National Research Council (CNR) and by AIRC. G.M. is supported by a fellowship from AIRC.
Received October 7, 1996; first decision October 29, 1996; accepted November 29, 1996.
|
References |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
1. Sporn MB, Roberts AB, Wakefield LM, Assonian RK. Transforming growth factor-ß: biological function and chemical structure. Science. 1986;233:532-534.
2. Massagué J. The transforming growth factor-beta family. Annu Rev Cell Biol. 1990;6:597-641.
3.
Sporn MB, Roberts AB. Transforming growth
factor-ß: recent progress and new challenges. J Cell
Biol. 1992;119:1017-1021.
4. Border WA, Ruoslanhti E. Transforming growth factor-ß in disease: the dark side of tissue repair. J Clin Invest. 1992;90:1-7.
5.
Border WA, Noble NA. Transforming growth factor
ß in tissue fibrosis. N Engl J Med. 1994;331:1286-1292.
6. Wahl SM, McCartney-Francis N, Mergenhagen SE. Inflammatory and immunomodulatory roles of TGF-ß. Immunol Today. 1989;10:258-261.[Medline] [Order article via Infotrieve]
7. Wahl S. Transforming growth factor beta (TGF-ß) in inflammation: a cause and a cure. J Clin Immunol. 1992;12:61-74.[Medline] [Order article via Infotrieve]
8.
Gibbons GH, Dzau VJ. The emerging concept of
vascular remodeling. N Engl J Med. 1994;330:1431-1438.
9. Frohlich ED, Apstein C, Chobanian AV, Devereux RB, Dustan HP, Dzau V, Fauad-Tarazi F, Horan MJ, Marcus M, Massie B, Pfeffer MA, Re RN, Roccella EJ, Savage D, Shub C. The heart in hypertension. N Engl J Med. 1992;327:998-1008.[Medline] [Order article via Infotrieve]
10. Sarzani R, Brecher P, Chobanian AV. Growth factor expression in aorta of normotensive and hypertensive rats. J Clin Invest. 1989;83:1404-1408.
11.
Agrotis A, Saltis J, Bobik A. Transforming
growth factor-ß1 gene activation and growth of smooth
muscle from hypertensive rats. Hypertension. 1994;23:593-599.
12.
Nabel EG, Shum L, Pompili VJ, Yang Z-Y, San H, Shu HB,
Liptay S, Gold L, Gordon D, Derynck R, Nabel GJ. Direct transfer
of transforming growth factor ß1 gene into arteries
stimulates fibrocellular hyperplasia. Proc Natl Acad Sci
U S A. 1993;90:10759-10763.
13.
Weber KT, Brilla CG. Pathological
hypertrophy and cardiac interstitium: fibrosis and
renin-angiotensin-aldosterone system.
Circulation. 1991;83:1849-1865.
14. Weber KT, Sun Y, Guarda E. Structural remodeling in hypertensive heart disease and the role of hormones. Hypertension. 1994;23(part 2):869-877.
15.
Villarreal FJ, Dillmann WH. Cardiac
hypertrophy-induced changes in mRNA levels for TGF-ß1,
fibronectin, and collagen. Am J Physiol. 1992;262:H1861-H1866.
16. Takahashi N, Calderone A, Izzo NJ, Maki TM, Marsh JD, Colucci WS. Hypertrophic stimuli induce transforming growth factor ß1 expression in rat ventricular myocytes. J Clin Invest. 1994;94:1470-1476.
17.
Kehrl JH, Wakefield LM, Roberts AB, Jakowlew S,
Alvarez-Mon M, Derynck R, Sporn MB, Fauci AS. Production
of transforming growth factor ß by human T lymphocytes and its
potential role in the regulation of T cell growth. J Exp
Med. 1986;163:1037-1050.
18.
Assoian RK, Fleurdelys BE, Stevenson HC, Miller PJ,
Madtes DK, Raines EW, Ross R, Sporn MB. Expression and secretion
of type beta transforming growth factor by activated human
macrophages. Proc Natl Acad Sci U S A. 1987;84:6020-6024.
19. Grotendorst GR, Smale G, Pencev D. Production of transforming growth factor beta by human peripheral blood monocytes and neutrophils. J Cell Physiol. 1989;140:396-402.[Medline] [Order article via Infotrieve]
20.
Clozel M, Kuhn H, Hefti F, Baumgartner HR.
Endothelial dysfunction and
subendothelial monocyte macrophages in
hypertension: effect of angiotensin converting enzyme
inhibition. Hypertension. 1991;18:132-141.
21.
Haller H, Behrend M, Park JK, Schaberg T, Luft FC,
Distler A. Monocyte infiltration and c-fms expression
in hearts of spontaneously hypertensive rats.
Hypertension. 1995;25:132-138.
22. Hinglais N, Heudes D, Nicoletti A, Mandet C, Laurent M, Bariety J, Michel J-B. Colocalization of myocardial fibrosis and inflammatory cells in rats. Lab Invest. 1994;70:286-294.[Medline] [Order article via Infotrieve]
23.
McCarron RM, Wang L, Siren AL, Spatz M, Hallenbeck
JM. Monocyte adhesion to cerebromicrovascular
endothelial cells derived from hypertensive and
normotensive rats. Am J Physiol. 1994;267:H2491-H2497.
24. Ross R. The pathogenesis of atherosclerosis: a perspective for 1990s. Nature (Lond). 1993;362:801-809.[Medline] [Order article via Infotrieve]
25. Muller FB, Laragh JH. Clinical evaluation and differential diagnosis of the individual hypertensive patient. In: Laragh JH, Brenner BM, eds. Hypertension: Pathophysiology, Diagnosis, and Management. New York, NY: Raven Press Publishers; 1990:1385-1396.
26.
Sahn DJ, De Maria A, Kisslo J, Weyman A.
Recommendation regarding quantitation in M-mode
echocardiography: results of a survey of
echocardiographic measurements.
Circulation. 1978;58:1072-1083.
27.
Devereux RB, Reichek N.
Echocardiographic determination of left
ventricular mass in man: anatomic validation of the
method. Circulation. 1977;55:613-618.
28.
Pignoli P, Tremoli E, Poli A, Oreste P, Paoletti
R. Intimal plus medial thickness of the arterial
wall: a direct measurement with ultrasound imaging.
Circulation. 1986;74:1399-1406.
29. Boyum A. Isolation of mononuclear cells and granulocytes from human blood. J Clin Lab Invest. 1968;21:77-89.[Medline] [Order article via Infotrieve]
30. Conti P, Panara MR, Barbacane R, Placido FC, Bongrazio M, Reale M, Dempsy RA, Fiore S. Blocking the interleukin-1 receptor inhibits leukotriene B4 and prostaglandin E2 generation in human monocyte cultures. Cell Immunol. 1992;145:199-209.[Medline] [Order article via Infotrieve]
31. Miyazono K, Yuki K, Takaku F, Wernstedt C, Kanzaki T, Olofsson A, Hellman U, Heldin CH. Latent forms of TGF-ß: structure and biology. Ann N Y Acad Sci. 1990;593:51-58.[Medline] [Order article via Infotrieve]
32. Danielpour DD, Dart LL, Flander KC, Roberts AB, Sporn MB. Immunodetection and quantification of two forms of transforming growth factor beta (TGF-ß1 and TGF-ß2) secreted by cells in culture. J Cell Physiol. 1989;138:79-86.[Medline] [Order article via Infotrieve]
33. Chomczynski P, Sacchi N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol chloroform extraction. Anal Biochem. 1987;162:156-159.[Medline] [Order article via Infotrieve]
34. Bondjers G, Glukhova M, Hansson GK, Postnov YV, Reidy MA, Schwartz SM. Hypertension and atherosclerosis: cause and effect, or two effects with one unknown cause? Circulation. 1991;84(suppl VI):VI-2-VI-16.
35. Roman MJ, Pickering TG, Schwartz JE, Pini R, Devereux RB. Association of carotid atherosclerosis and left ventricular hypertrophy. J Am Coll Cardiol. 1995;25:83-90.[Abstract]
36. Botney MD, Bahadori L, Gold LI. Vascular remodeling in primary pulmonary hypertension. Am J Pathol. 1994;144:286-295.[Abstract]
37. Connor TB, Roberts AB, Sporn MB, Danielpour D, Dart LL, Michels RG, de Bustyros S, Enger C, Kato H, Lansing M, Hayashi H, Glaser BM. Correlation of fibrosis and transforming growth factor-ß type 2 levels in the eye. J Clin Invest. 1989;83:1661-1666.
38.
Kulozik M, Hogg A, Lankat-Buttgereit B, Krieg T.
Co-localization of transforming growth factor ß2 with 
1(I)
procollagen mRNA in tissue sections of patients with systemic
sclerosis. J Clin Invest. 1990;86:917-922.
39. Hahn AWA, Resink TJ, Bemhardt J, Ferracin F, Buhler FR. Stimulation of autocrine platelet-derived growth factor AA-homodimer and transforming growth factor ß in vascular smooth muscle cells. Biochem Biophys Res Commun. 1991;178:1451-1458.[Medline] [Order article via Infotrieve]
40. Dzau VJ. Cell biology and genetics of angiotensin in cardiovascular disease. J Hypertens. 1994;12(suppl 4):S3-S10.
41. Dzau VJ. Circulating versus local renin-angiotensin system in cardiovascular homeostasis. Circulation. 1988;77(suppl I):I-4-I-13.
42.
Johnston CI. Tissue angiotensin
converting enzyme in cardiac and vascular hypertrophy,
repair, and remodeling. Hypertension. 1994;23:258-268.
43.
Kim S, Ohta K, Hamaguchi A, Omura T, Yukimura T, Miura
K, Inada Y, Ischimura Y, Chatani F, Iwao H.
Angiotensin II type I receptor antagonist
inhibits the gene expression of transforming growth factor-beta1 and
extracellular matrix in cardiac and vascular tissues of hypertensive
rats. J Pharmacol Exp Ther. 1995;273:509-515.
44. Thomas DW, Hoffman MD. Identification of macrophage receptors for angiotensin: a potential role in antigen uptake for T lymphocyte responses? J Immunol. 1984;132:2807-2812.[Abstract]
This article has been cited by other articles:
 |
|
 |
|
  M. Saura, C. Zaragoza, B. Herranz, M. Griera, L. Diez-Marques, D. Rodriguez-Puyol, and M. Rodriguez-Puyol Nitric Oxide Regulates Transforming Growth Factor-{beta} Signaling in Endothelial Cells Circ. Res., November 25, 2005; 97(11): 1115 - 1123. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Peng, O. A. Carretero, D. R. Brigstock, N. Oja-Tebbe, and N.-E. Rhaleb Ac-SDKP Reverses Cardiac Fibrosis in Rats With Renovascular Hypertension Hypertension, December 1, 2003; 42(6): 1164 - 1170. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Romano, M. T. Guagnano, G. Pacini, S. Vigneri, A. Falco, M. Marinopiccoli, M. R. Manigrasso, S. Basili, and G. Davi Association of Inflammation Markers with Impaired Insulin Sensitivity and Coagulative Activation in Obese Healthy Women J. Clin. Endocrinol. Metab., November 1, 2003; 88(11): 5321 - 5326. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. J. Lindsberg and A. J. Grau Inflammation and Infections as Risk Factors for Ischemic Stroke Stroke, October 1, 2003; 34(10): 2518 - 2532. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Porreca, C. Di Febbo, G. Baccante, M. Di Nisio, and F. Cuccurullo Increased transforming growth factor-beta1 circulating levels and production in human monocytes after 3-hydroxy-3-methyl-glutaryl-coenzyme a reductase inhibition with pravastatin J. Am. Coll. Cardiol., June 5, 2002; 39(11): 1752 - 1757. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Dorffel, C. Latsch, B. Stuhlmuller, S. Schreiber, S. Scholze, G. R. Burmester, and J. Scholze Preactivated Peripheral Blood Monocytes in Patients With Essential Hypertension Hypertension, July 1, 1999; 34(1): 113 - 117. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Bobik, A. Agrotis, P. Kanellakis, R. Dilley, A. Krushinsky, V. Smirnov, E. Tararak, M. Condron, and G. Kostolias Distinct Patterns of Transforming Growth Factor-ß Isoform and Receptor Expression in Human Atherosclerotic Lesions : Colocalization Implicates TGF-ß in Fibrofatty Lesion Development Circulation, June 8, 1999; 99(22): 2883 - 2891. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Suthanthiran, B. Li, J. O. Song, R. Ding, V. K. Sharma, J. E. Schwartz, and P. August Transforming growth factor-beta 1 hyperexpression in African-American hypertensives: A novel mediator of hypertension and/or target organ damage PNAS, March 28, 2000; 97(7): 3479 - 3484. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||