Effects of Tanshinone VI on the Hypertrophy of Cardiac Myocytes and Fibrosis of Cardiac Fibroblasts of Neonatal Rats

Abstract

The possible effects of tanshinone VI (tsh), a diterpene from the root of Tan-Shen (Salvia miltiorrhiza, Bunge (Labiatae)) on hypertrophy and fibrosis in cultured neonatal rat cardiac myocytes and fibroblasts were examined. Tsh had no significant effect on protein synthesis, which was evaluated by [³ H]-leucine incorporation into the acid insoluble fraction in the cells, in the absence of stimulatory factors in cardiac myocytes. The amount of protein produced in cardiac myocytes was increased by 10 ^{- 8} M endothelin-1 (ET-1), 10 ^{- 6} M phenylephrine (PE), or 10 ^{- 8} M insulin-like growth factor-1 (IGF-1), suggesting that hypertrophy of cardiac myocytes in vitro was induced by these factors. The ET-1-, PE-, or IGF-1-induced increase in protein synthesis was attenuated by treatment with 10 ^{- 5} M tsh. Treatment with 10 ^{- 5} M tsh significantly decreased the synthesis of collagen by cardiac fibroblasts, which was evaluated by [³ H]-proline incorpolation into acid-insoluble fraction of the fiblobrasts, in the absence of stimulatory factors for the production. Fetal bovine serum (FBS) or IGF-1 increased collagen synthesis in a concentration-dependent manner. The increase at 5 % FBS or 10 ^{- 8} M IGF-1 was inhibited by 10 ^{- 5} M tsh. Fibroblast-conditioned medium (FB-CM) increased protein synthesis in cardiac myocytes in a concentration-dependent manner (10˜ - 100 %). Tsh attenuated the FB-CM-induced increase in protein synthesis by cardiac myocytes. These results show that tsh may attenuate the humoral factor-induced hypertrophy of cardiac myocytes and fibrosis of cardiac fibroblasts. The findings suggest that tsh may improve the development of cardiac remodeling under pathophysiological conditions.

Abbreviations

ANP:atrial natriuretic peptide

DMEM:Dulbecco-modified Eagle's medium

ET-1:endothelin-1

FB-CM:fibroblast-conditioned medium

FBS:fetal bovine serum

IGF-1:insulin-like growth factor-1

PE:phenylephrine

tsh:tanshinone VI

Key words

Collagen - culture - fibroblasts - hypertrophy - myocytes - tanshinone VI - Salvia miltiorrhiza - Lamiaceae

References

• 1 Horio T, Nishikimi T, Yoshihara F, Matsuo H, Takishita S, Kangawa K. Inhibitory regulation of hypertrophy by endogenous atrial natriuretic peptide in cultured cardiac myocytes.  Hypertension. 2000;  35 19-24
• 2 Yoshida H, Takahashi M, Tanonaka K, Maki T, Nasa Y, Takeo S. Effects of ACE inhibition and angiotensin II type 1 receptor blockade on cardiac function and G proteins in rats with chronic heart failure.  Br J Pharmacol. 2001;  134 150-60
• 3 Chien K R, Zhu H, Knowlton K U, Miller-Hance W, van-Bilsen M, O’Brien T X, Evans S M. Transcriptional regulation during cardiac growth and development.  Ann Rev Physiol. 1993;  55 77-95
• 4 Huang X, Yang B, Huang H, Xu Y, Hu Z. Studies on the active principles of Dan-Shen III. Search for plant resources containing tanshinone II-A.  Chih Wu Hsueh. 1980;  22 98-100
• 5 Chen Z. Chinese traditional medicines. Some recent studies of Chinese medical plants.  Kagaku no Ryoiki. 1981;  35 494-501
• 6 Takeo S, Tanonaka K, Hirai K, Kawaguchi K, Ogawa M, Yagi A, Fujimoto K. Beneficial effect of tan-shen, an extract from the root of Salvia, on post-hypoxic recovery of cardiac contractile force.  Biochem Pharmacol. 1990;  40 1137-43
• 7 Harada M, Itoh H, Nakagawa O, Ogawa Y, Miyamoto Y, Kuwahara K, Ogawa E, Igaki T, Yamashita J, Masuda I, Yoshimasa T, Tanaka I, Saito Y, Nakao K. Significance of ventricular myocytes and nonmyocytes interaction during cardiocyte hypertrophy: evidence for endothelin-1 as a paracrine hypertrophic factor from cardiac nonmyocytes.  Circulation. 1997;  96 3737-44
• 8 Kuwahara K, Saito Y, Harada M, Ishikawa M, Ogawa E, Miyamoto Y, Hamanaka I, Kamitani S, Kajiyama N, Takahashi N, Nakagawa O, Masuda I, Nakao K. Involvement of cardiotrophin-1 in cardiac myocyte-nonmyocyte interactions during hypertrophy of rat cardiac myocytes in vitro .  Circulation. 1999;  100 1116-24
• 9 Maki T, Horio T, Yoshihara F, Tokudome T, Suga S, Kawano Y, Takeo S, Kangawa K. Endogenous insulin-like growth factor-1 promotes collagen production and myocyte hypertrophy in an autocrine and paracrine manner in cultured neonatal rat cardiac fibroblasts and myocytes.  Circulation. 2001;  104 II-186
• 10 Yagi A, Fujimoto K, Tanonaka K, Hirai K, Takeo S. Possible active components of Tan-Shen (Salvia miltiorrhiza) for protection of the myocardium against ischemia-induced derangements.  Planta Med. 1989;  55 51-4
• 11 Okamura N, Kobayashi K, Yagi A, Kitazawa T, Shimomura K. High-performance liquid chromatography of abietane-type compounds.  J Chromatogr. 1991;  542 317-26
• 12 Maki T, Horio T, Yoshihara F, Suga S, Takeo S, Matsuo H, Kangawa K. Effect of neutral endopeptidase inhibitor on endogenous atrial natriuretic peptide as a paracrine factor in cultured cardiac fibroblasts.  Br J Pharmacol. 2000;  131 1204-10
• 13 Ebensperger R, Acevedo E, Melendez J, Corbalan R, Acevedo M, Sapag-Hagar M, Jalil J E, Lavandero S. Selective increase in cardiac IGF-1 in a rat model of ventricular hypertrophy.  Biochem Biophys Res Commun. 1998;  243 20-4
• 14 Mulder P, Richard V, Derumeaux G, Hogie M, Henry J P, Lallemand F, Compagnon P, Mace B, Comoy E, Letac B, Thuillez C. Role of endogenous endothelin in chronic heart failure: effect of long- term treatment with an endothelin antagonist on survival, hemodynamics, and cardiac remodeling.  Circulation. 1997;  96 1976-82
• 15 Esler M, Kaye D. Sympathetic nervous system activation in essential hypertension, cardiac failure and psychosomatic heart disease.  J Cardiovasc Pharmacol. 2000;  35 S1-7
• 16 Sakai S, Miyauchi T, Kobayashi M, Yamaguchi I, Goto K, Sugishita Y. Inhibition of myocardial endothelin pathway improves long-term survival in heart failure.  Nature. 1996;  384 353-5
• 17 Donohue T J, Dworkin L D, Lango M N, Fliegner K, Lango R P, Benstein J A, Slater W R, Catanese V M. Induction of myocardial insulin-like growth factor-I gene expression in left ventricular hypertrophy.  Circulation. 1994;  89 799-809
• 18 Maki T, Nasa Y, Yamaguchi F, Yoshida H, Mori M, Takada T, Horikawa E, Okano K, Takeo S. Long-term treatment with neutral endopeptidase inhibitor improves cardiac function and reduces natriuretic peptides in rats with chronic heart failure.  Cardiovasc Res. 2001;  51 608-17