Discovery of Potent and Selective A Antagonists with Efficacy in Animal Models of Parkinson's Disease and Depression.

Adenosine A receptor (AAdoR) antagonism is a nondopaminergic approach to Parkinson's disease treatment that is under development. Earlier we had reported the therapeutic potential of 7-methoxy-4-morpholino-benzothiazole derivatives as AAdoR antagonists. We herein described a novel series of [1,2,4]triazolo[5,1-]purin-2-one derivatives that displays functional antagonism of the A receptor with a high degree of selectivity over A, A, and A receptors.

Design and synthesis of novel xanthine derivatives as potent and selective A adenosine receptor antagonists for the treatment of chronic inflammatory airway diseases.

Adenosine induces bronchial hyperresponsiveness and inflammation in asthmatics through activation of A adenosine receptor (AAdoR). Selective antagonists have been shown to attenuate airway reactivity and improve inflammatory conditions in pre-clinical studies. Hence, the identification of novel, potent and selective AAdoR antagonist may be beneficial for the potential treatment of asthma and Chronic Obstructive Pulmonary Disease (COPD).

Design, Synthesis of Novel, Potent, Selective, Orally Bioavailable Adenosine A Receptor Antagonists and Their Biological Evaluation.

Our initial structure-activity relationship studies on 7-methoxy-4-morpholino-benzothiazole derivatives featured by aryloxy-2-methylpropanamide moieties at the 2-position led to identification of compound 25 as a potent and selective A adenosine receptor (AAdoR) antagonist with reasonable ADME and pharmacokinetic properties. However, poor intrinsic solubility and low to moderate oral bioavailability made this series unsuitable for further development. Further optimization using structure-based drug design approach resulted in discovery of potent and selective adenosine A receptor antagonists bearing substituted 1-methylcyclohexyl-carboxamide groups at position 2 of the benzothiazole scaffold and endowed with better solubility and oral bioavailability.

A adenosine receptor antagonists: Design, synthesis and biological evaluation of novel xanthine derivatives.

AdoR is a low affinity adenosine receptor that functions by Gs mediated elevation of cAMP and subsequent downstream signaling. The receptor has been implicated in lung inflammatory disorders like COPD and asthma. Several potent and selective AAdoR antagonists have been reported in literature, however most of the compounds suffer from poor pharmacokinetic profile.

Differential expression and role of p21cip/waf1 and p27kip1 in TNF-alpha-induced inhibition of proliferation in human glioma cells.

Background: The role of TNF-alpha in affecting the fate of tumors is controversial, while some studies have reported apoptotic or necrotic effects of TNF-alpha, others provide evidence that endogenous TNF-alpha promotes growth and development of tumors. Understanding the mechanism(s) of TNF-alpha mediated growth arrest will be important in unraveling the contribution of tissue associated macrophages in tumor resistance. The aim of this study was to investigate the role of Cyclin Dependent Kinase Inhibitors (CDKI)--21cip/waf1 and p27kip1 in TNF-alpha mediated responses in context with p53 and activation of NF-kappaB and Akt pathways.

ROS-triggered caspase 2 activation and feedback amplification loop in beta-carotene-induced apoptosis.

Reactive oxygen species (ROS) and caspases 8, 9, and 3 are reported to be crucial players in apoptosis induced by various stimuli. Recently, caspase 2 has been implicated in stress-induced apoptosis but the exact mechanism remains unclear. In this study, we report that ROS generation led to activation of caspase 2 during beta-carotene-induced apoptosis in the human leukemic T cell line Molt 4.

Upregulation of survivin in G2/M cells and inhibition of caspase 9 activity enhances resistance in staurosporine-induced apoptosis.

Survivin, a member of the inhibitor of apoptosis (IAP) gene family, plays an important role in both the regulation of cell cycle and the inhibition of apoptosis, and is frequently overexpressed in many tumor types. In neuroblastomas, the expression of survivin correlates with a more aggressive and histologically unfavorable disease. Survivin is predominantly a cytoplasmic protein that is expressed in a cell cycle-dependent manner, increasing in the G2/M phase of the cell cycle followed by a rapid decline in the G1 phase.