Transforming growth factor-beta1 levels in hypertensive patients: association with body mass index and leptin.

Abstract

BACKGROUND:

Transforming growth factor-beta1 (TGF-beta1) has been demonstrated to be overexpressed in hypertension. Leptin, an adipocyte product, has been shown to play a role in obesity-related hypertension and in vitro studies demonstrated a biologic interaction between leptin and TGF-beta1. Thus, we evaluate a possible in vivo association between TGF-beta1, body mass index (BMI), and leptin circulating levels in hypertensive subjects.

METHODS:

Blood samples for fasting leptin and TGF-beta1, were evaluated in 29 overweight, 46 obese, and 29 nonobese hypertensive patients before and after a 12-week calorie-restricted diet. Monocyte cultures were used for in vitro experiments.

RESULTS:

Transforming growth factor-beta1 was significantly elevated in hypertensive obese patients (n = 46) as compared with TGF-beta1 levels of hypertensive patients with normal BMI (n = 29) (8. 9 +/- 3 ng/mL v 4.4 +/- 2; P < .001). The circulating levels of TGF-beta1 were associated with BMI and leptin levels in an univariate analysis (r = 0.59, P < .0001; r = 0.62, P < .0001, respectively) and these associations were still present after stepwise multivariate analysis. Weight loss of 10% produced a parallel decrease in TGF-beta1 (from 8.9 +/- 3 ng/mL to 5.3 +/- 2.8 ng/mL; P < .01) and leptin levels (from 30 +/- 24 ng/mL to 17 +/- 14; P < .05). In vitro experiments showed that leptin is able to induce a dose-dependent increase in TGF-beta1 production and mRNA expression in human monocyte cultures.

CONCLUSIONS:

Our data indicate that TGF-beta1 levels are positively associated with BMI and leptin levels in hypertensive patients and suggest that adipose tissue may be an important determinant of TGF-beta1 levels possibly by a leptin-dependent pathway.

• Authors: Ettore Porreca, Concetta Di Febbo, Ester Vitacolonna, Giovanna Baccante, Augusto Di Castelnuovo, Antonio Angelini, Francesca Febo, Marcello Di Nisio, Franco Cuccurullo
• Journal: American journal of hypertension (Am J Hypertens) Vol. 15 Issue 9 Pg. 759-65 (Sep 2002) ISSN: 0895-7061 [Print] United States
• PMID: 12219869 (Publication Type: Evaluation Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Leptin
• RNA, Messenger
• Transforming Growth Factor beta

Topics

• Adult
• Blood Pressure (physiology)
• Body Mass Index
• Female
• Gene Expression (genetics)
• Humans
• Hypertension (blood, complications, physiopathology)
• In Vitro Techniques
• Leptin (blood)
• Male
• Middle Aged
• Obesity (blood, complications, physiopathology)
• RNA, Messenger (genetics)
• Regression Analysis
• Transforming Growth Factor beta (blood, genetics)
• Weight Loss (physiology)