The discovery, design and synthesis of potent agonists of adenylyl cyclase type 2 by virtual screening combining biological evaluation

Cobalt(II)-Catalyzed [2 + 2 + 2]/[4 + 2] Cycloaddition of 1,6-Heptadiynes with Maleimides

An efficient method for the synthesis of the polycyclic molecules via cobalt-catalyzed [2 + 2 + 2] followed by [4 + 2] consecutive cycloaddition reaction strategy has been devised. Sequential cycloaddition reactions of substituted 1,6-diynes with maleimides have been performed. This tandem cycloaddition approach has yielded polyheterocyclic compounds exhibiting remarkable diastereoselectivity and achieving yields ranging from good to excellent. Additionally, a potential reaction mechanism has been proposed to explain the observed cycloaddition process.

Functional and pathological roles of adenylyl cyclases in various diseases

Adenylyl cyclases (ADCYs) produce the second messengers cAMP, which is crucial for a number of cellular activities. There are ten isoforms in the mammalian ADCY family including nine transmembrane adenylyl cyclases (tmAC) and one soluble adenylyl cyclase (sAC/ADCY10). There have been numerous studies demonstrating the importance of ADCYs in the development of a wide range of diseases, including cardiovascular disease, neurological disease, liver disease, and tumors. The classification, structure and regulation of ADCYs are discussed in this overview, which is followed by an analysis of how ADCYs are involved in various disorders and how they are used as a therapeutic tool. Our objective is to get a more thorough understanding of ADCYs to aid future study and provide novel ideas for the treatment of particular diseases.

Synthesis of Aryl Naphthoquinones and Maleimides via Pd(II)-Catalyzed Template-Assisted m-C(sp2)-H Functionalization Reaction

An efficient approach for the synthesis of substituted aryl naphthoquinones via a Pd(II)-catalyzed template-assisted m-C(sp2)-H bond functionalization reaction of arylmethane sulfonates have been demonstrated. The method involves usage of less expensive and abundant pharmacologically important scaffold naphthoquinone. A wide range of arylmethane sulfonates were examined and found to be compatible with the protocol. The protocol has also been further extended to the synthesis of various substituted aryl maleimide scaffolds. A plausible reaction mechanism has also been proposed to account for the selective distal m-C(sp2)-H bond functionalization reaction.

Biochemical pharmacology of adenylyl cyclases in cancer

Globally, despite extensive research and pharmacological advancement, cancer remains one of the most common causes of mortality. Understanding the signaling pathways involved in cancer progression is essential for the discovery of new drug targets. The adenylyl cyclase (AC) superfamily comprises glycoproteins that regulate intracellular signaling and convert ATP into cyclic AMP, an important second messenger. The present review highlights the involvement of ACs in cancer progression and suppression, broken down for each specific mammalian AC isoform. The precise mechanisms by which ACs contribute to cancer cell proliferation and invasion are not well understood and are variable among cancer types; however, AC overactivation, along with that of downstream regulators, presents a potential target for novel anticancer therapies. The expression patterns of ACs in numerous cancers are discussed. In addition, we highlight inhibitors of AC-related signaling that are currently under investigation, with a focus on possible anti-cancer strategies. Recent discoveries with small molecules regarding more direct modulation AC activity are also discussed in detail. A more comprehensive understanding of different components in AC-related signaling could potentially lead to the development of novel therapeutic strategies for personalized oncology and might enhance the efficacy of chemoimmunotherapy in the treatment of various cancers.

Integrating network toxicology and molecular docking to explore the toxicity of the environmental pollutant butyl hydroxyanisole: An example of induction of chronic urticaria

The study aimed to comprehensively investigate environmental pollutants' potential toxicity and underlying molecular mechanisms, focusing on chronic urticaria (CU) induced by butylated hydroxyanisole (BHA) exposure, further drawing public awareness regarding the potential risks of environmental pollutants, applying ChEMBL, STITCH, and SwissTargetPrediction databases to predict the targets of BHA, CTD, GeneCards, and OMIM databases to collect the relevant targets of CU. Ultimately, we identified 81 potential targets of BHA-induced CU and extracted 31 core targets, including TNF, SRC, CASP3, BCL2, IL2, and MMP9. GO and KEGG enrichment analyses revealed that these core targets were predominantly involved in cancer signaling, estrogen and endocrine resistance pathways. Furthermore, molecular docking confirmed the ability of BHA to bind with core targets. The onset and development of CU may result from BHA by affecting multiple immune signaling pathways. Our study elucidated the molecular mechanisms of BHA toxicity and its role in CU induction, providing the basis for preventing and treating chronic urticaria associated with environmental BHA exposure.

Structural insights into membrane adenylyl cyclases, initiators of cAMP signaling

Membrane adenylyl cyclases (ACs) catalyze the conversion of ATP to the ubiquitous second messenger cAMP. As effector proteins of G protein-coupled receptors and other signaling pathways, ACs receive and amplify signals from the cell surface, translating them into biochemical reactions in the intracellular space and integrating different signaling pathways. Despite their importance in signal transduction and physiology, our knowledge about the structure, function, regulation, and molecular interactions of ACs remains relatively scarce. In this review, we summarize recent advances in our understanding of these membrane enzymes.

Rhodium(III)-Catalyzed C-H Cascade Annulation of Arylhydrazines with 2-Diazo-1,3-indandiones for the Synthesis of Tetracyclic Indeno[1,2-b]indoles

An efficient approach for the preparation of tetracyclic indeno[1,2-b]indoles via Rh(III)-catalyzed C-H cascade annulation between arylhydrazines and diazo indan-1,3-diones has been established. In addition, a series of indeno[1,2-b]indoles were obtained in up to 96% yield with a wide range of substrates and high functional group tolerance. Finally, the diverse transformations of the desired products demonstrate the synthetic utility and utilization of this protocol.

Concise Synthesis of Spirocyclic Dihydrophthalazines through Spiroannulation Reactions of Aryl Azomethine Imines with Cyclic Diazo Compounds

Spiroannulation reactions are fundamental and invaluable for the synthesis of spirocyclic compounds. Presented herein are novel cascade reactions of aryl azomethine imines with cyclic diazo compounds leading to the formation of spirocyclic dihydrophthalazine derivatives. Based on experimental mechanistic studies, the formation of the title products is believed to go through azomethine imine-assisted cylcometalation, Rh-carbene formation through dediazonization, and migratory insertion followed by reductive elimination and azomethine imine ring opening. Control experiments revealed that air acts as an effective and sustainable co-oxidant to facilitate the cascade reaction. In general, this concise synthesis of the unprecedented spirocyclic dihydrophthalazine derivatives has advantages such as easily accessible substrates, good functional group compatibility, mild reaction conditions, high efficiency and selectivity, and excellent atom-economy. In addition, the value of this protocol is underlined by its ready scalability and divergent derivation of products.

Isoforskolin, an adenylyl cyclase activator, attenuates cigarette smoke-induced COPD in rats

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by limited airflow due to pulmonary and alveolar abnormalities from exposure to cigarette smoke (CS). Current therapeutic drugs are limited and the development of novel treatments to prevent disease progression is challenging. Isoforskolin (ISOF) from the plant Coleus forskohlii is an effective activator of adenylyl cyclase (AC) isoforms. Previously we found ISOF could attenuate acute lung injury in animal models, while the effect of ISOF on COPD has not been elucidated.

PURPOSE

In this study, we aimed to evaluate the efficacy of ISOF on COPD and reveal its potential mechanisms.

METHODS

A rat model of COPD was established by long-term exposure to CS, then the rats were orally administered with ISOF (0.5, 1 and 2 mg/kg). The pulmonary function, lung morphology, inflammatory cells and cytokines in serum or bronchoalveolar lavage fluid (BALF) were evaluated. Transcriptomics, proteomics and network pharmacology analysis were utilized to identify potential mechanisms of ISOF. Droplet digital PCR was used to detect the mRNA expression of AC1-10 in donor lung tissues. AC activation was determined in recombinant human embryonic kidney 293 (HEK293) cells stably expressing human AC isoforms. In addition, ISOF caused trachea relaxation ex vivo were assessed in isolated trachea rings from guinea pigs.

RESULTS

ISOF significantly ameliorated pathological damage of lung tissue and improved pulmonary function in COPD rats. ISOF treatment decreased the number of inflammatory cells in peripheral blood, and also the levels of pro-inflammatory cytokines in serum and BALF. Consistent with omics-based analyses, ISOF markedly downregulated the mTOR level in lung tissue. Flow cytometry analysis revealed that ISOF treatment reduced the ratio of Th17/Treg cells in peripheral blood. Furthermore, the expression levels of AC1 and AC2 are relatively higher than other AC isoforms in normal lung tissues, and ISOF could potently activate AC1 and AC2 in vitro and significantly relax isolated guinea pig trachea.

CONCLUSION

Collectively, our studies suggest that ISOF exerts its anti-COPD effect by improving lung function, anti-inflammation and trachea relaxation, which may be related to AC activation, mTOR signaling and Th17/Treg balance.

Exploring the biochemical properties of three polyphenol oxidases from blueberry (Vaccinium corymbosum L.)

Purification of blueberry polyphenol oxidase (PPO) has not been substantially progressed for a long time, which leads to little further study. We purified three PPOs from blueberries for the first time by modified Native-Page. The PPO-2 consists of two subunits (68 and 36 kDa), whereas PPO-3 and PPO-4 contain only one subunit (36 kDa). The optimum pH and temperature of PPO-2, PPO-3, and PPO-4 were 5.8-6.2 and 40 °C-45 °C with catechol as a substrate. The optimal substrates for them were all catechol (K_m = 14.91, 7.19, and 11.20, respectively). High-pressure processing (HPP) had a limited inhibitory effect on the three PPOs. The activities of PPO-2, PPO-3, and PPO-4 were significantly reduced with increased SDS concentration. The binding of substrate to catalytic cavity is related to the residues His76, His209, His213, Gly228, and Phe230. The carbonyl group of residue Gly228 is one of the key sites for screening substrates.