Identification of nocamycin biosynthetic gene cluster from Saccharothrix syringae NRRL B-16468 and generation of new nocamycin derivatives by manipulating gene cluster.

Background: Nocamycins I and II, produced by the rare actinomycete Saccharothrix syringae, belong to the tetramic acid family natural products. Nocamycins show potent antimicrobial activity and they hold great potential for antibacterial agent design. However, up to now, little is known about the exact biosynthetic mechanism of nocamycin.

[Effect of tanshinone II(A) on expression of different components in renin-angiotensin system of left ventricles of hypertensive rats].

Objective: To investigate the effect of tanshinone II(A) on the expression of different components in the renin-angiotensin system of left ventricles of renal hypertensive rats.

Method: The renal hypertension model was established in rats by the two-kidney-one-clip (2K1C) method. In the experiment, all of the rats were randomly divided into four groups (n = 15 per group) before the operation: the sham-operated (Sham) group, the hypertensive model (Model) group, the low-dose tanshinone II(A) group and the high-dose tanshinone II(A) group.

Tetramethylpyrazine inhibits angiotensin II-induced cardiomyocyte hypertrophy and tumor necrosis factor-α secretion through an NF-κB-dependent mechanism.

Tetramethylpyrazine (TMP), a bioactive compound isolated from the Chinese herb, Ligusticum wallichii Franchat, has been reported to play a protective role in cardiac diseases. However, the cellular and molecular mechanisms behind the protective effects of TMP on the heart remain to be elucidated. In this study, we aimed to determine the effects of TMP on angiotensin II (Ang II)-induced hypertrophy in neonatal rat cardiomyocytes and its possible mechanisms of action.

Endothelin-1 stimulates the expression of L-type Ca2+ channels in neonatal rat cardiomyocytes via the extracellular signal-regulated kinase 1/2 pathway.

The cardiac L-type Ca(2+) channel current (I(Ca,L)) plays an important role in controlling both cardiac excitability and excitation-contraction coupling and is involved in the electrical remodeling during postnatal heart development and cardiac hypertrophy. However, the possible role of endothelin-1 (ET-1) in the electrical remodeling of postnatal and diseased hearts remains unclear. Therefore, the present study was designed to investigate the transcriptional regulation of I(Ca,L) mediated by ET-1 in neonatal rat ventricular myocytes using the whole-cell patch-clamp technique, quantitative RT-PCR and Western blotting.