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Elaeodendron is a genus of tiny trees, shrubs, vines, and herbs consisting of about 23 species. It is used in traditional medicine and has a wide range of pharmacological activities. From the plants in this genus, flavonoids, terpenoids, cardiac glycosides, and cardenolides have been isolated. Elaeodendron species have been the subject of numerous in vitro investigations; however, not many vivo studies are available. Preclinical investigations have also revealed antiviral, anti-HIV, anticancer, antiproliferative, antioxidant, antifungal, anti-inflammation, cytotoxic, anti-plasmodial, anti-arthritic, antibacterial, and anti-diabetic activities. Bioactive substances found in Elaedendron that function in a variety of ways are related to these biological processes. Several databases, including PubMed, Scopus, etc., were searched using keywords such as “Elaeodendron”, “chemical constituents”, “anti-cancer”, “anti-viral”, “pharmacology”, etc., to perform a comprehensive review of the current literature. In this sense, this review intends to provide the most recent developments in the ethnomedical use of Elaeodendron species, and their therapeutic benefits and bioactive compounds. Many species of this genus are reported to be toxic. To provide stronger scientific support for their conventional usage, more in vivo and clinical research for mechanism-based pharmacological evaluation as well as toxicological studies should be carried out in the future.

In this Letter we describe structure-activity relationship (SAR) studies conducted in five distinct regions of a new 2-amino-N-phenylacetamides series of Slack potassium channel inhibitors exemplified by recently disclosed high-throughput screening (HTS) hit VU0606170 (4). New analogs were screened in a thallium (Tl

Human neuropeptide Y receptors (Y1R, Y2R, Y4R, and Y5R) belong to the superfamily of G protein-coupled receptors and play an important role in the regulation of food intake and energy metabolism. We identified and characterized the first selective Y4R allosteric antagonist (S)-VU0637120, an important step toward validating Y receptors as therapeutic targets for metabolic diseases. To obtain insight into the antagonistic mechanism of (S)-VU0637120, we conducted a variety of in vitro, ex vivo, and in silico studies. These studies revealed that (S)-VU0637120 selectively inhibits native Y4R function and binds in an allosteric site located below the binding pocket of the endogenous ligand pancreatic polypeptide in the core of the Y4R transmembrane domains. Taken together, our studies provide a first-of-its-kind tool for probing Y4R function and improve the general understanding of allosteric modulation, ultimately contributing to the rational development of allosteric modulators for peptide-activated G protein-coupled receptors (GPCRs).

Malignant migrating partial seizures of infancy is a rare, devastating form of epilepsy most commonly associated with gain-of-function mutations in the potassium channel, Slack. Not only is this condition almost completely pharmacoresistant, there are not even selective drug-like tools available to evaluate whether inhibition of these overactivated, mutant Slack channels may represent a viable path forward toward new antiepileptic therapies. Therefore, we used a high-throughput thallium flux assay to screen a drug-like, 100 000-compound library in search of inhibitors of both wild-type and a disease-associated mutant Slack channel. Using this approach, we discovered VU0606170, a selective Slack channel inhibitor with low micromolar potency. Critically, VU0606170 also proved effective at significantly decreasing the firing rate in overexcited, spontaneously firing cortical neuron cultures. Taken together, our data provide compelling evidence that selective inhibition of Slack channel activity can be achieved with small molecules and that inhibition of Slack channel activity in neurons produces efficacy consistent with an antiepileptic effect. Thus, the identification of VU0606170 provides a much-needed tool for advancing our understanding of the role of the Slack channel in normal physiology and disease as well as its potential as a target for therapeutic intervention.

Background Although NGLY1 is known as a pivotal enzyme that catalyses the deglycosylation of denatured glycoproteins, information regarding the responses of human cancer and normal cells to NGLY1 suppression is limited. Methods We examined how NGLY1 expression affects viability, tumour growth, and responses to therapeutic agents in melanoma cells and an animal model. Molecular mechanisms contributing to NGLY1 suppression-induced anticancer responses were revealed by systems biology and chemical biology studies. Using computational and medicinal chemistry-assisted approaches, we established novel NGLY1-inhibitory small molecules. Results Compared with normal cells, NGLY1 was upregulated in melanoma cell lines and patient tumours. NGLY1 knockdown caused melanoma cell death and tumour growth retardation. Targeting NGLY1 induced pleiotropic responses, predominantly stress signalling-associated apoptosis and cytokine surges, which synergise with the anti-melanoma activity of chemotherapy and targeted therapy agents. Pharmacological and molecular biology tools that inactivate NGLY1 elicited highly similar responses in melanoma cells. Unlike normal cells, melanoma cells presented distinct responses and high vulnerability to NGLY1 suppression. Conclusion Our work demonstrated the significance of NGLY1 in melanoma cells, provided mechanistic insights into how NGLY1 inactivation leads to eradication of melanoma with limited impact on normal cells, and suggested that targeting NGLY1 represents a novel anti-melanoma strategy.

Human neuropeptide Y receptors (Y

Background Helicobacter pylori is a bacterium that affects about 50% of the world population and, despite being often asymptomatic, it is responsible of several gastric diseases, from gastritis to gastric cancer. The protein Lpp20 (HP1456) plays an important role in bacterium survival and host colonization, but the possibility that it might be involved in the etiology of H. pylori-related disorders is an unexplored issue. Lpp20 is a lipoprotein bound to the external membrane of the bacterium, but it is also secreted inside vesicles along with other two proteins of the same operon, i.e. HP1454 and HP1457. Results In this study we determined the crystal structure of Lpp20 and we found that it has a fold similar to a carcinogenic factor released by H. pylori, namely Tipα. We demonstrate that Lpp20 promotes cell migration and E-cadherin down-regulation in gastric cancer cells, two events recalling the epithelial–mesenchymal transition (EMT) process. Differently from Tipα, Lpp20 also stimulates cell proliferation. Conclusions This identifies Lpp20 as a new pathogenic factor produced by H. pylori that promotes EMT and thereby the progression of cancer to the metastatic state.

Although NGLY1 is known as a pivotal enzyme that catalyzes the deglycosylation of denatured glycoproteins, information regarding the responses of human cancer and normal cells to NGLY1 suppression is limited. While studying the NGLY1 deficiency-caused neurodevelopmental variations in patients with a congenital deglycosylation disorder, we made an intriguing discovery that the expression of NGLY1 appears to be dysregulated in human melanoma cells. We have examined how NGLY1 expression affects viability, tumor growth, and responses to therapeutic agents in melanoma cells and an animal model. Molecular mechanisms contributing to NGLY1 suppression-induced anticancer responses were revealed by systems biology and chemical biology studies. Using computational and medicinal chemistry-assisted approaches, we established novel NGLY1-inhibitory small molecules. Compared with normal cells, NGLY1 was upregulated in melanoma cell lines and patient tumors. NGLY1 knockdown caused melanoma cell death and tumor growth retardation. Targeting NGLY1 in melanoma cells induced pleiotropic responses, predominantly stress signaling-associated apoptosis and cytokine surges, which synergize with the antimelanoma activity of standard chemotherapy and targeted therapy agents. Pharmacologic and molecular biology tools that inactivate NGLY1 elicited highly similar responses in melanoma cells. Unlike normal cells, melanoma cells presented distinct responses and high vulnerability to NGLY1 suppression. Our work demonstrated the significance of NGLY1 in melanoma cells, provided mechanistic insights into how NGLY1 inactivation leads to eradication of melanoma with limited impact on normal cells, and suggested that targeting NGLY1 represents a novel antimelanoma strategy with the opportunity of a broad therapeutic window. Citation Format: Victor Lin, Ashwini Zolekar, Nigam Mishra, Yin Ying Ho, Hamed Hayatshahi, Abhishek Parab, Rohit Sampat, Xiaoyan Liao, Peter Hoffmann, Jin Liu, Kyle Emmitte, Yu-Chieh Wang. Identification of NGLY1-mediated protein deglycosylation as a vulnerable point in melanoma [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr A28.