Antitumoral, antihypertensive, antimicrobial, and antioxidant effects of an octanuclear copper(II)-telmisartan complex with an hydrophobic nanometer hole.

A new Cu(II) complex with the antihypertensive drug telmisartan, [Cu8Tlm16]·24H2O (CuTlm), was synthesized and characterized by elemental analysis and electronic, FTIR, Raman and electron paramagnetic resonance spectroscopy. The crystal structure (at 120 K) was solved by X-ray diffraction methods. The octanuclear complex is a hydrate of but otherwise isostructural to the previously reported [Cu8Tlm16] complex. [Cu8Tlm16]·24H2O crystallizes in the tetragonal P4/ncc space group with a = b = 47.335(1), c = 30.894(3) Å, Z = 4 molecules per unit cell giving a macrocyclic ring with a double helical structure. The Cu(II) ions are in a distorted bipyramidal environment with a somewhat twisted square basis, cis-coordinated at their core N2O2 basis to two carboxylate oxygen and two terminal benzimidazole nitrogen atoms. Cu8Tlm16 has a toroidal-like shape with a hydrophobic nanometer hole, and their crystal packing defines nanochannels that extend along the crystal c-axis. Several biological activities of the complex and the parent ligand were examined in vitro. The antioxidant measurements indicate that the complex behaves as a superoxide dismutase mimic with improved superoxide scavenger power as compared with native sartan. The capacity of telmisartan and its copper complex to expand human mesangial cells (previously contracted by angiotensin II treatment) is similar to each other. The antihypertensive effect of the compounds is attributed to the strongest binding affinity to angiotensin II type 1 receptor and not to the antioxidant effects. The cytotoxic activity of the complex and that of its components was determined against lung cancer cell line A549 and three prostate cancer cell lines (LNCaP, PC-3, and DU 145). The complex displays some inhibitory effect on the A549 line and a high viability decrease on the LNCaP (androgen-sensitive) line. From flow cytometric analysis, an apoptotic mechanism was established for the latter cell line. Telmisartan and CuTlm show antibacterial and antifungal activities in various strains, and CuTlm displays improved activity against the Staphylococcus aureus strain as compared with unbounded copper(II).

Tripeptides as Integrin-Linked Kinase Modulating Agents Based on a Protein-Protein Interaction with α-Parvin.

Integrin-linked kinase (ILK) has emerged as a controversial pseudokinase protein that plays a crucial role in the signaling process initiated by integrin-mediated signaling. However, ILK also exhibits a scaffolding protein function inside cells, controlling cytoskeletal dynamics, and has been related to non-neoplastic diseases such as chronic kidney disease (CKD). Although this protein always acts as a heterotrimeric complex bound to PINCH and parvin adaptor proteins, the role of parvin proteins is currently not well understood. Using in silico approaches for the design, we have generated and prepared a set of new tripeptides mimicking an α-parvin segment. These derivatives exhibit activity in phenotypic assays in an ILK-dependent manner without altering kinase activity, thus allowing the generation of new chemical probes and drug candidates with interesting ILK-modulating activities.

Tweak up-regulates endothelin-1 system in mouse and human endothelial cells.

AIM: To analyse the ability of TWEAK to modify the endothelin system, particularly endothelin-1 (ET-1) and endothelin-converting enzyme-1 (ECE-1), studying the intracellular mechanisms implied. TNF-like weak inducer of apoptosis (TWEAK) is a member of TNF superfamily; it has different biological functions such as inflammation, angiogenesis, proliferation, and apoptosis. TWEAK and fibroblast growth-factor-inducible 14 are expressed in different cell types, including endothelial and smooth muscle cells. Despite their presence in endothelial cells, the effect of TWEAK on endothelial function is incompletely defined. METHODS AND RESULTS: In cells, TWEAK induced protein (Western blot) and mRNA (quantitative polymerase chain reaction) expression of ECE-1. Results were related to transcriptional changes, as ECE-1 promoter activity (transfection assays) was also increased. Transfections with serial deletions of ECE-1 promoter suggest a potential role for AP-1 and NFkB, which were confirmed by electrophoretic mobility shift assays. When AP-1 or NFkB activations were inhibited by specific inhibitors of AP-1, PD-98059 (Erk1/2 inhibitor), or SP-600125 (JNK inhibitor), and also with an inhibitor of NFKB and PDTC, TWEAK effect was partially blocked in both cases, suggesting that both transcription factors are implied in ECE-1 regulation. Moreover, the endothelial changes induced by TWEAK were also tested in vivo, using 3-month-old male CD-1 mice treated with TWEAK 10 µg/kg body weight for 24 h, finding similar effects, a rise in ET-1 production (enzyme-linked immunosorbent assay), and ECE-1 expression in aorta and lung tissues. Mice showed slight hypertension after 4 h of treatment, which disappeared at 24 h. CONCLUSIONS: In pathological situations such as chronic inflammation, TWEAK could be more harmful through this effect at endothelial level. Pharmacological blockade of this cytokine could prevent the haemodynamic and structural changes related to an increased ET-1 synthesis.