The monoamine neurotransmitter, 5-Hydroxytryptamine or serotonin, is derived from tryptophan and synthesized both centrally and systemically. Fourteen structurally and functionally distinct receptor subtypes have been identified for serotonin, each of which mediates the neurotransmitter's effects through a range of downstream signaling molecules and effectors. Although it is most frequently described for its role in the etiology of neuropsychiatric and mood disorders, serotonin has been implicated in a slew of fundamental physiological processes, including apoptosis, mitochondrial biogenesis, cell proliferation and migration. Its roles as the neurotransmitter have also emerged in pathogenic conditions ranging from anorexia nervosa to cancer. This has necessitated the understanding of the signaling mechanisms underlying the serotonergic system, which led us to construct a consolidative pathway map, which will provide as a resource for future biomedical investigation on this pathway. Using a set of stringent NetPath annotation criteria, we manually curated molecular reactions associated with serotonin and its receptors from publicly available literature; the reaction categories included molecular associations, activation/inhibition, post-translation modification, transport, and gene regulation at transcription and translational level. We identified 90 molecules in serotonin-serotonin receptor pathway. We submitted the curated data to NetPath, a publicly available database of human signaling pathways, in order to enable the wider scientific community to readily access data and contribute further to this pathway.

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Background. With 214 million cases and 438,000 deaths in 2015, malaria remains one of the deadliest infectious diseases in tropical countries. Several species of the protozoan Plasmodium cause malaria. However, almost all the fatalities are due to Plasmodium falciparum, a species responsible for the severest cases including cerebral malaria. Immune response to Plasmodium falciparum infection is mediated by the production of pro-inflammatory cytokines, chemokines and growth factors whose actions are crucial for the control of the parasites. Following this response, the induction of anti-inflammatory immune mediators downregulates the inflammation thus preventing its adverse effects such as damages to various organs and death.Methods. We performed a retrospective, nonprobability sampling study using clinical data and sera samples from patients, mainly adults, suffering of non-cerebral or cerebral malaria in Dakar, Sénégal. Healthy individuals residing in the same area were included as controls. We measured the serum levels of 29 biomarkers including growth factors, chemokines, inflammatory and anti-inflammatory cytokines.Results. We found an induction of both pro- and anti-inflammatory immune mediators during malaria. The levels of pro-inflammatory biomarkers were higher in the cerebral malaria than in the non-cerebral malaria patients. In contrast, the concentrations of anti-inflammatory cytokines were comparable in these two groups or lower in CM patients. Additionally, four pro-inflammatory biomarkers were significantly increased in the deceased of cerebral malaria compared to the survivors. Regarding organ damage, kidney failure was significantly associated with death in adults suffering of cerebral malaria.Conclusions. Our results suggest that a poorly controlled inflammatory response determines a bad outcome in African adults suffering of cerebral malaria.

Bradykinin, a member of the kallikrein‐kinin system (KKS), is associated with an inflammatory response pathway with diverse vascular permeability functions, including thrombosis and blood coagulation. In majority, bradykinin signals through Bradykinin Receptor B2 (B2R). B2R is a G protein‐coupled receptor (GPCR) coupled to G protein family such as Gαqs, Gαq/Gα11, Gαi1, and Gβ1γ2. B2R stimulation leads to the activation of a signaling cascade of downstream molecules such as phospholipases, protein kinase C, Ras/Raf‐1/MAPK, and PI3K/AKT and secondary messengers such as inositol‐1,4,5‐trisphosphate, diacylglycerol and Ca2+ ions. These secondary messengers modulate the production of nitric oxide or prostaglandins. Bradykinin‐mediated signaling is implicated in inflammation, chronic pain, vasculopathy, neuropathy, obesity, diabetes, and cancer. Despite the biomedical importance of bradykinin, a resource of bradykinin‐mediated signaling pathway is currently not available. Here, we developed a pathway resource of signaling events mediated by bradykinin. By employing data mining strategies in the published literature, we describe an integrated pathway reaction map of bradykinin consisting of 233 reactions. Bradykinin signaling pathway events included 25 enzyme catalysis reactions, 12 translocations, 83 activation/inhibition reactions, 11 molecular associations, 45 protein expression and 57 gene regulation events. The pathway map is made publicly available on the WikiPathways Database with the ID URL: https://www.wikipathways.org/index.php/Pathway:WP5132. The bradykinin‐mediated signaling pathway map will facilitate the identification of novel candidates as therapeutic targets for diseases associated with dysregulated bradykinin signaling.

Calcium/calmodulin‐dependent protein kinase kinase 2 (CAMKK2) is a serine/threonine‐protein kinase belonging to the Ca2+/calmodulin‐dependent protein kinase subfamily. CAMKK2 has an autocatalytic site, which gets exposed when Ca2+/calmodulin (CAM) binds to it. This results in autophosphorylation and complete activation of CAMKK2. The three major known downstream targets of CAMKK2 are 5′‐adenosine monophosphate (AMP)‐activated protein kinase (AMPKα), calcium/calmodulin‐dependent protein kinase 1 (CAMK1) and calcium/calmodulin‐dependent protein kinase 4 (CAMK4). Activation of these targets by CAMKK2 is important for the maintenance of different cellular and physiological processes within the cell. CAMKK2 is found to be important in neuronal development, bone remodeling, adipogenesis, and systemic glucose homeostasis, osteoclastgensis and postnatal myogensis. CAMKK2 is reported to be involved in pathologies like Duchenne muscular dystrophy, inflammation, osteoporosis and bone remodeling and is also reported to be overexpressed in prostate cancer, hepatic cancer, ovarian and gastric cancer. CAMKK2 is involved in increased cell proliferation and migration through CAMKK2/AMPK pathway in prostate cancer and activation of AKT in ovarian cancer. Although CAMKK2 is a molecule of great importance, a public resource of the CAMKK2 signaling pathway is currently lacking. Therefore, we carried out detailed data mining and documentation of the signaling events associated with CAMKK2 from published literature and developed an integrated reaction map of CAMKK2 signaling. This resulted in the cataloging of 285 reactions belonging to the CAMKK2 signaling pathway, which includes 33 protein–protein interactions, 74 post‐translational modifications, 7 protein translocation events, and 22 activation/inhibition events. Besides, 124 gene regulation events and 25 activator/inhibitors involved in CAMKK2 activation were also cataloged. The CAMKK2 signaling pathway map data is made freely accessible through WikiPathway database (https://www.wikipathways.org/index.php/Pathway:WP4874). We expect that data on a signaling map of CAMKK2 will provide the scientific community with an improved platform to facilitate further molecular as well as biomedical investigations on CAMKK2 and its utility in the development of biomarkers and therapeutic targets.

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Although CAMKK2 is overexpressed in several cancers, its role and relevant downstream signaling pathways in gastric cancer (GC) are poorly understood. Treatment of AGS GC cells with a CAMKK2 inhibitor, STO‐609, resulted in decreased cell proliferation, cell migration, invasion, colony‐forming ability, and G1/S‐phase arrest. Quantitative phosphoproteomics in AGS cells with the CAMKK2 inhibitor led to the identification of 9603 unique phosphosites mapping to 3120 proteins. We observed decreased phosphorylation of 1101 phosphopeptides (1.5‐fold) corresponding to 752 proteins upon CAMKK2 inhibition. Bioinformatics analysis of hypo‐phosphorylated proteins revealed enrichment of MAPK1/MAPK3 signaling. Kinase enrichment analysis of hypo‐phosphorylated proteins using the X2K Web tool identified ERK1, cyclin‐dependant kinase 1 (CDK1), and CDK2 as downstream substrates of CAMKK2. Moreover, inhibition of CAMKK2 and MEK1 resulted in decreased phosphorylation of ERK1, CDK1, MCM2, and MCM3. Immunofluorescence results were in concordance with our mass spectroscopy data and Western blot analysis results. Taken together, our data reveal the essential role of CAMKK2 in the pathobiology of GC through the activation of the MEK/ERK1 signaling cascade.

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