The novel piperazine-containing compound LQFM018: Necroptosis cell death mechanisms, dopamine D4 receptor binding and toxicological assessment.

Piperazine is a promising scaffold for drug development due to its broad spectrum of biological activities. Based on this, the new piperazine-containing compound LQFM018 (2) [ethyl 4-((1-(4-chlorophenyl)-1H-pyrazol-4-yl)methyl)piperazine-1-carboxylate] was synthetized and some biological activities investigated. In this work, we described its ability to bind aminergic receptors, antiproliferative effects as well as the LQFM018 (2)-triggered cell death mechanisms, in K562 leukemic cells, by flow cytometric analyses. Furthermore, acute oral systemic toxicity and potential myelotoxicity assessments of LQFM018 (2) were carried out. LQFM018 (2) was originally obtained by molecular simplification from LASSBio579 (1), an analogue compound of clozapine, with 33% of global yield. Binding profile assay to aminergic receptors showed that LQFM018 (2) has affinity for the dopamine D4 receptor (Ki = 0.26 µM). Moreover, it showed cytotoxicity in K562 cells, in a concentration and time-dependent manner; IC50 values obtained were 399, 242 and 119 µM for trypan blue assay and 427, 259 and 50 µM for MTT method at 24, 48 or 72 h, respectively. This compound (427 µM) also promoted increase in LDH release and cell cycle arrest in G2/M phase. Furthermore, it triggered necrotic morphologies in K562 cells associated with intense cell membrane rupture as confirmed by Annexin V/propidium iodide double-staining. LQFM018 (2) also triggered mitochondrial disturb through loss of ΔΨm associated with increase of ROS production. No significant accumulation of cytosolic cytochrome c was verified in treated cells. Furthermore, it was verified an increase of expression of TNF-R1 and mRNA levels of CYLD with no involviment in caspase-3 and -8 activation and NF-κB in K562 cells. LQFM018 (2) showed in vitro myelotoxicity potential, but it was orally well tolerated and classified as UN GHS category 5 (LD50 > 2000-5000 mg/Kg). Thus, LQFM018 (2) seems to have a non-selective action considering hematopoietic cells. In conclusion, it is suggested LQFM018 (2) promotes cell death in K562 cells via necroptotic signaling, probably with involvement of dopamine D4 receptor. These findings open new perspectives in cancer therapy by use of necroptosis inducing agents as a strategy of reverse cancer cell chemoresistance.

Adenosine A2A receptor agonist prevents cardiac remodeling and dysfunction in spontaneously hypertensive male rats after myocardial infarction.

BACKGROUND: This work evaluated the hypothesis that 3,4-methylenedioxybenzoyl-2-thienylhydrazone (LASSBio-294), an agonist of adenosine A2A receptor, could be beneficial for preventing cardiac dysfunction due to hypertension associated with myocardial infarction (MI). METHODS: Male spontaneously hypertensive rats (SHR) were randomly divided into four groups (six animals per group): sham-operation (SHR-Sham), and myocardial infarction rats (SHR-MI) were treated orally either with vehicle or LASSBio-294 (10 and 20 mg.kg-1.d-1) for 4 weeks. Echocardiography and in vivo hemodynamic parameters measured left ventricle (LV) structure and function. Exercise tolerance was evaluated using a treadmill test. Cardiac remodeling was accessed by LV collagen deposition and tumor necrosis factor α expression. RESULTS: Early mitral inflow velocity was significantly reduced in the SHR-MI group, and there was significant recovery in a dose-dependent manner after treatment with LASSBio-294. Exercise intolerance observed in the SHR-MI group was prevented by 10 mg.kg-1.d-1 of LASS-Bio-294, and exercise tolerance exceeded that of the SHR-Sham group at 20 mg.kg-1.d-1. LV end-diastolic pressure increased after MI, and this was prevented by 10 and 20 mg.kg-1.d-1 of LASSBio-294. Sarcoplasmic reticulum Ca2+ ATPase levels were restored in a dose-dependent manner after treatment with LASSBio-294. Fibrosis and inflammatory processes were also counteracted by LASSBio-294, with reductions in LV collagen deposition and tumor necrosis factor α expression. CONCLUSION: In summary, oral administration of LASSBio-294 after MI in a dose-dependent manner prevented the development of cardiac dysfunction, demonstrating this compound's potential as an alternative treatment for heart failure in the setting of ischemic heart disease with superimposed chronic hypertension.

Antihypertensive profile of 2-thienyl-3,4-methylenedioxybenzoylhydrazone is mediated by activation of the A2A adenosine receptor.

Several N-acylhydrazone derivatives synthesized from safrole have been found to promote intense vasodilation and antihypertensive activity. The present work describes the synthesis and antihypertensive profile of 2-thienyl-3,4-methylenedioxybenzoylhydrazone (LASSBio-1027), a new analogue of the lead compound 3,4-methylenedioxybenzoyl-2-thienylhydrazone. Thoracic aortas from Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR) were prepared for isometric tension recording. Noninvasive blood pressure measurements were made during 14 days of intraperitoneal (10 mg/kg) or oral (20 mg/kg) administration of LASSBio-1027. LASSBio-1027 exhibited partially endothelium-dependent vasorelaxant activity, which was attenuated in the presence of l-NAME, glibenclamide, or ZM 241385. LASSBio-1027 exhibited an antihypertensive effect in SHR during 14 days of intraperitoneal or oral administration, but did not induce a hypotensive effect in normotensive WKY rats. LASSBio-1027-induced vascular relaxation of aortas from WKY rats was mediated by the activation of A(2A) adenosine receptors. Docking studies and binding assays suggested that LASSBio-1027 has affinity for A(2A) and A(3) adenosine receptors. This new N-acylhydrazone derivative represents a potential strategy for the treatment of arterial hypertension.

Synthesis and anti-platelet activity of novel arylsulfonate--acylhydrazone derivatives, designed as antithrombotic candidates.

In this work, we describe a new class of promising anti-platelet drug candidates with significant antithrombotic activity in vivo. This new series of compounds was structurally planned by modification of known thrombin inhibitors based on the use of acylhydrazone subunit, as a nonpeptide scaffold, and variations at P1 moiety. Three different families of arylsulfonate-acylhydrazone derivatives were designed. The bioassays indicated the first class of derivatives represented by 4f (LASSBio-693) and 4j (LASSBio-743), which were active in inhibiting the platelet aggregation induced by thrombin. The second class represented by compounds 4e (LASSBio-774) and 4h (LASSBio-480) that selectively inhibit the platelet aggregation involving TXA(2) formation. Finally, the third class of derivatives was identified acting as a novel symbiotic agent able to inhibit the platelet aggregation induced by collagen or AA and by thrombin, represented by compounds 4b (LASSBio-694) and 4g (LASSBio-770).

Design, synthesis and antiinflammatory activity of novel phthalimide derivatives, structurally related to thalidomide.

As part of an ongoing effort to develop new thalidomide analogues as antiinflammatory lead-candidates, this paper describes the synthesis and antiinflammatory activity of novel N-phenyl-phthalimide functionalized derivatives (4a-d, 5a,b, 6a,b). The target compounds were assayed in an acute lung inflammatory model and all compounds were able to inhibit TNF-alpha production and subsequent neutrophil recruitment in the LPS-acute lung inflammatory model.

Synthesis and anti-inflammatory activity of phthalimide derivatives, designed as new thalidomide analogues.

This paper describes the synthesis and anti-inflammatory activity of new N-phenyl-phthalimide sulfonamides (3a-e) and the isosters N-phenyl-phthalimide amides (4a-e), designed as hybrids of thalidomide (1) and aryl sulfonamide phosphodiesterase inhibitor (2). In these series, compound 3e (LASSBio 468), having a sulfonyl-thiomorpholine moiety, showed potent inhibitory activity on LPS-induced neutrophil recruitment with ED(50)=2.5mg kg(-1), which was correlated with its inhibitory effect on TNF-alpha level.