Carboxyamidotriazole: a novel inhibitor of both cAMP-phosphodiesterases and cGMP-phosphodiesterases

A modular systems biological modelling framework studies cyclic nucleotide signaling in platelets

BACKGROUND

The cyclic nucleotides cAMP and cGMP inhibit platelet activation. Different platelet signaling modules work together. We develop here a modelling framework to integrate different signaling modules and apply it to platelets.

RESULTS

We introduce a novel standardized bilinear coupling mechanism allowing sub model debugging and standardization of coupling with optimal data driven modelling by methods from optimization. Besides cAMP signaling our model considers specific cGMP effects including external stimuli by drugs. Moreover, the output of the cGMP module serves as input for a modular model of VASP phosphorylation and for the activity of cAMP and cGMP pathways in platelets. Experimental data driven modeling allows us to design models with quantitative output. We use the condensed information about involved regulation and system responses for modeling drug effects and obtaining optimal experimental settings. Stepwise further validation of our model is given by direct experimental data.

CONCLUSIONS

We present a general framework for model integration using modules and their stimulus responses. We demonstrate it by a multi-modular model for platelet signaling focusing on cGMP and VASP phosphorylation. Moreover, this allows to estimate drug action on any of the inhibitory cyclic nucleotide pathways (cGMP, cAMP) and is supported by experimental data.

Recent advances in nanoscale materials for antibody-based cancer theranostics

The quest for advanced management tools or options of various cancers has been on the rise to efficiently reduce their risks of mortality without the demerits of conventional treatments (e.g., undesirable side effects of the medications on non-target tissues, non-targeted distribution, slow clearance of the administered drugs, and the development of drug resistance over the duration of therapy). In this context, nanomaterials-antibody conjugates can offer numerous advantages in the development of cancer theranostics over conventional delivery systems (e.g., highly specific and enhanced biodistribution of the drug in targeted tissues, prolonged systemic circulation, low toxicity, and minimally invasive molecular imaging). This review comprehensively discusses and evaluates recent advances in the application of nanomaterial-antibody bioconjugates for cancer theranostics for the further advancement in the control of diverse cancerous diseases. Further, discussion is expanded to cover the various challenges and limitations associated with the design and development of nanomaterial-antibody conjugates applicable towards better management of cancer.

Isatin-azole hybrids and their anticancer activities

Isatin and azole moieties, which have the ability to form various noncovalent interactions with different therapeutic targets, are common pharmacophores in drug development. Isatin and azole derivatives possess promising in vitro and in vivo anticancer activity, and many of them, such as semaxanib, sunitinib, and carboxyamidotriazole, could be used to treat various cancers. Thus, it is conceivable that hybridization of the isatin moiety with azole may provide a valuable therapeutic intervention for the treatment of cancer. Substantial efforts have been made to develop isatin-azole hybrids as novel anticancer agents, and some of the isatin-azole hybrids exhibited considerable activity. This review emphasizes isatin-azole hybrids with potential anticancer activity, covering articles published between 2010 and 2019. The structure-activity relationships as well as the mechanisms of action are also discussed to provide insights for the rational design of more effective candidates.

Effect of fermented Cordyceps sinensis on doxorubicin‑induced cardiotoxicity in rats

Cordyceps sinensis (CS) is a prominent medicinal herb in traditional Chinese medicine, and fermented CS is frequently used as a substitute for natural CS. Doxorubicin (DOX), an antitumor drug used in chemotherapy, is limited by its poor cardiotoxicity. The aim of the present study was to evaluate the protective effect of fermented CS against DOX-induced cardiotoxicity and the potential underlying mechanisms. Male Sprague-Dawley rats (180–200 g) were randomly assigned to seven different treatment groups: Normal control, DOX control, DOX+captopril (0.05 g/kg), 0.75, 1.5 and 3 g/kg DOX+CS, and the CS (1.5 g/kg) control. Histopathological changes, cardiac energy metabolism, cyclic adenosine monophosphate (cAMP) signaling and the associated mRNA expression of AMP-activated protein kinase (AMPK) were then evaluated. Fermented CS decreased the left ventricular weight index, heart weight index and mortality; however, it increased diastolic blood pressure and mean arterial pressure. In addition, it shortened the duration of the QRS complex and Sα-T segment, decreased serum creatine kinase (CK) and aspartate aminotransferase activity, inhibited histopathological changes and reduced brain natriuretic peptide content. Treatment with fermented CS also increased the activities of superoxide dismutase and glutathione peroxidase, reduced malondialdehyde content, increased the mitochondrial activities of Na⁺K⁺-adenosine 5′-triphosphate (ATP) ase, Ca²⁺Mg²⁺-ATPase and CK, and increased the creatine phosphate/ATP ratio and AMP/ATP ratio. Furthermore, it decreased the ATP/adenosine 5′-diphosphate (ADP) ratio, upregulated AMPKα2 expression, reduced the activity of serum phosphodiesterases (PDEs) and increased myocardial cAMP content. The results of the present study demonstrated that fermented CS attenuated DOX-induced cardiotoxicity by inhibiting myocardial hypertrophy and myocardial damage, ameliorating systolic function and the antioxidant enzyme system, improving cardiac energy metabolism, depressing the activities of PDEs, and by upregulating the cAMP and AMPK signaling pathways. Thus, fermented CS may be a candidate for the prevention of DOX-induced cardiotoxicity, cardiac energy impairment and against a number of cardiac diseases.

The rational search for PDE10A inhibitors from Sophora flavescens roots using pharmacophore‑ and docking‑based virtual screening

Phosphodiesterase 10A (PDE10A) has been confirmed to be an important target for the treatment of central nervous system (CNS) disorders. The purpose of the present study was to identify PDE10A inhibitors from herbs used in traditional Chinese medicine. Pharmacophore and molecular docking techniques were used to virtually screen the chemical molecule database of Sophora flavescens, a well‑known Chinese herb that has been used for improving mental health and regulating the CNS. The pharmacophore model generated recognized the common functional groups of known PDE10A inhibitors. In addition, molecular docking was used to calculate the binding affinity of ligand‑PDE10A interactions and to investigate the possible binding pattern. Virtual screening based on the pharmacophore model and molecular docking was performed to identify potential PDE10A inhibitors from S. flavescens. The results demonstrated that nine hits from S. flavescens were potential PDE10A inhibitors, and their biological activity was further validated using literature mining. A total of two compounds were reported to inhibit cyclic adenosine monophosphate phosphodiesterase, and one protected against glutamate‑induced oxidative stress in the CNS. The remaining six compounds require further bioactivity validation. The results of the present study demonstrated that this method was a time‑ and cost‑saving strategy for the identification of bioactive compounds from traditional Chinese medicine.

Therapeutic efficacy of carboxyamidotriazole on 2,4,6-trinitrobenzene sulfonic acid-induced colitis model is associated with the inhibition of NLRP3 inflammasome and NF-κB activation

Excess proinflammatory cytokines owing to the activation of NF-κB and NLRP3 inflammasome play the key role in inflammatory bowel disease (IBD). Previously, we reported the anti-inflammatory activity of carboxyamidotriazole (CAI) resulting from decreasing cytokines. Therefore, we investigated the therapeutic effects of CAI in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced rat colitis and the involvement of CAI action with NLRP3 inflammasome and NF-κB pathway. CAI was orally administered to TNBS-induced colitis rat. The severity of colitis was assessed, and NLRP3 inflammasome, NF-κB pathway and cytokines were determined. Our results showed that CAI significantly reduced weight loss and disease activity index (DAI) scores in colitis rats and alleviated the colonic macroscopic signs and pathological damage. In addition, the intestinal inflammatory markers and permeability index were markedly ameliorated by CAI treatment. The decreased levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, IL-18 were also detected in the colon tissues of CAI-treated colitis rats. Moreover, the activation of NLRP3 inflammasome in inflamed colon was significantly suppressed by showing an obvious reduction in the NLRP3 and activated caspase-1 levels. Furthermore, CAI reduced NF-κB p65 expression and IκBα phosphorylation and degradation in colitis rats. Therefore, CAI attenuates TNBS-induced colitis, which may be attributed to its inhibition of NLRP3 inflammasome and NF-κB activation, and down-regulation of proinflammatory cytokines. These results provide further understanding of the intestinal anti-inflammatory effect of CAI and highlight it as a potential drug for the treatment of IBD.

Carboxyamidotriazole alleviates muscle atrophy in tumor-bearing mice by inhibiting NF-κB and activating SIRT1

Cancer cachexia is a complex disorder characterized by inflammatory responses, and it is associated with poor performance status and high mortality rate of cancer patients. Carboxyamidotriazole (CAI), a noncytotoxic chemotherapy agent, shows anti-inflammatory features in the treatment of many diseases. Here, we investigated the preventive and therapeutic effects of CAI on muscle loss that occurred in mice with advanced Lewis lung carcinoma (LLC). The carcass weights of CAI-treated mice were significantly higher than that of mice in the vehicle group from Day 19 to the end of the study. The gastrocnemius and epididymal adipose tissue weights were also increased by CAI treatment. The protective mechanisms might be attributed to the following points: CAI treatment inhibited the proteolysis in muscles by decreasing expressions of muscle-specific FoxO3 transcription factor and ubiquitin E3 ligases (MuRF1 and atrogin1). Moreover, CAI restricted the NF-κB signaling, downregulated the level of TNF-α in muscle and both TNF-α and IL-6 levels in serum, directly stimulated SIRT1 activity in vitro, and increased SIRT1 content in muscle. These results indicate that CAI can alleviate muscle wasting and is a promising drug against lung cancer cachexia.

A short review on structure and role of cyclic-3',5'-adenosine monophosphate-specific phosphodiesterase 4 as a treatment tool

Cyclic nucleotide phosphodiesterases (PDEs) are known as a super-family of enzymes which catalyze the metabolism of the intracellular cyclic nucleotides, cyclic-3',5'-adenosine monophosphate (cAMP), and cyclic-3',5'-guanosine monophosphate that are expressed in a variety of cell types that can exert various functions based on their cells distribution. The PDE4 family has been the focus of vast research efforts over recent years because this family is considered as a prime target for therapeutic intervention in a number of inflammatory diseases such as asthma, chronic obstructive pulmonary disease, and rheumatoid arthritis, and it should be used and researched by pharmacists. This is because the major isoform of PDE that regulates inflammatory cell activity is the cAMP-specific PDE, PDE4. This review discusses the relationship between PDE4 and its inhibitor drugs based on structures, cells distribution, and pharmacological properties of PDE4 which can be informative for all pharmacy specialists.

Phosphodiesterase-5 Inhibitors: Action on the Signaling Pathways of Neuroinflammation, Neurodegeneration, and Cognition

Phosphodiesterase type 5 inhibitors (PDE5-Is) have recently emerged as a potential therapeutic strategy for neuroinflammatory, neurodegenerative, and memory loss diseases. Mechanistically, PDE5-Is produce an anti-inflammatory and neuroprotection effect by increasing expression of nitric oxide synthases and accumulation of cGMP and activating protein kinase G (PKG), the signaling pathway of which is thought to play an important role in the development of several neurodiseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). The aim of this paper was to review present knowledge of the signaling pathways that underlie the use of PDE5-Is in neuroinflammation, neurogenesis, learning, and memory.