Role and therapeutic potential of dietary ketone bodies in lymph vessel growth

LERN, NAVBOLymphatic vessels (LVs), lined by lymphatic endothelial cells (LECs), are indispensable for life. However, the role of metabolism in LECs has been incompletely elucidated. In our study, it is reported that LEC-specific loss of OXCT1, a key enzyme of ketone body oxidation, reduces LEC proliferation, migration and vessel sprouting in vitro and impairs lymphangiogenesis in development and disease in Prox1ΔOXCT1 mice. Mechanistically, OXCT1 silencing lowers acetyl-CoA levels, tricarboxylic acid cycle metabolite pools, and nucleotide precursor and deoxynucleotide triphosphate levels required for LEC proliferation. Ketone body supplementation to LECs induces the opposite effects. Notably, elevation of lymph ketone body levels by a high-fat, low-carbohydrate ketogenic diet or by administration of the ketone body β-hydroxybutyrate increases lymphangiogenesis after corneal injury and myocardial infarction. Intriguingly, in a mouse model of microsurgical ablation of LVs in the tail, which repeats features of acquired lymphedema in humans, the ketogenic diet improves LV function and growth, reduces infiltration of anti-lymphangiogenic immune cells and decreases edema, suggesting a novel dietary therapeutic opportunity.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Ésteres del ácido fumárico para el tratamiento de la psoriasis, una enfermedad dependiente de angiogén

In 1959, the German chemist Schweckendiek postulated that psoriasis, a disease he himself suffered from, was caused by an alteration of the citric acid cycle and that an external addition of fumaric acid could reverse this pathology. Schweckendiek tried to test his hypothesis by ingesting fumaric acid esters (FAEs), as fumaric acid in its free form is highly irritating, and found that his psoriasis improved. Following the discovery of this capability of the FAEs, a pharmaceutical company named “Fumapharm” was born that began to market fumaric acid ester capsules whose dosage was one tablet three times a day, defining a maximum daily dose of 1.2 g.En 1959,el químico alemán Schweckendiek postuló que la psoriasis, enfermedad que él mismo padecía, era causada por una alteración del ciclo del ácido cítrico y que una adición externa de ácido fumárico podría revertirse dicha patología. Schweckendiek intentó probar su hipótesis ingiriendo ésteres de ácido fumárico (EAF), ya que el ácido fumárico en su forma libre es altamente irritante., y comprobó que su psoriasis mejoraba. Tras el descubrimiento de esta capacidad de los FAEs, nació una compañía farmaceútica bajo el nombre de “Fumapharm” que empezó a comercializar unas cápsulas de ésteres de fumárico cuya posología era un comprimido tres veces al día, definiendo una dosis máxima diaria de 1,2

Novel application assigned to toluquinol: inhibition of lymphangiogenesis by interfering with VEGF-C/VEGFR-3 signalling pathway

BACKGROUND AND PURPOSE Lymphangiogenesis is an important biological process associated with the pathogenesis of several diseases, including metastatic dissemination, graft rejection, lymphoedema and other inflammatory disorders. The development of new drugs that block lymphangiogenesis has become a promising therapeutic strategy. In this study, we investigated the ability of toluquinol, a 2-methyl-hydroquinone isolated from the culture broth of the marine fungus Penicillium sp. HL-85-ALS5-R004, to inhibit lymphangiogenesis in vitro, ex vivo and in vivo. EXPERIMENTAL APPROACH We used human lymphatic endothelial cells (LECs) to analyse the effect of toluquinol in 2D and 3D in vitro cultures and in the ex vivo mouse lymphatic ring assay. For in vivo approaches, the transgenic Fli1:eGFPy1 zebrafish, mouse ear sponges and cornea models were used. Western blotting and apoptosis analyses were carried out to search for drug targets. KEY RESULTS Toluquinol inhibited LEC proliferation,migration, tubulogenesis and sprouting of new lymphatic vessels. Furthermore, toluquinol induced apoptosis of LECs after 14 h of treatment in vitro, blocked the development of the thoracic duct in zebrafish and reduced the VEGF-C-induced lymphatic vessel formation and corneal neovascularization in mice. Mechanistically, we demonstrated that this drug attenuates VEGF-C-induced VEGFR-3 phosphorylation in a dose-dependentmanner and suppresses the phosphorylation of Akt and ERK1/2. CONCLUSIONS AND IMPLICATIONS Based on these findings, we propose toluquinol as a new candidate with pharmacological potential for the treatment of lymphangiogenesis-related pathologies. Notably, its ability to suppress corneal neovascularization paves the way for applications in vascular ocular pathologies.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. This work has been supported by personal funding by FP7-PEOPLE-2013-IEF Marie Curie Postdoctoral Fellowship (MGC). Acknowledged are the supporting grants from the Action de Recherche Concertée (ARC) (Université de Liège), the Fonds de la Recherche Scientifique-FNRS (F.R.S.-FNRS), the Foundation Against Cancer (foundation of public interest), the Centre Anticancéreux près l’Université de Liège, the Fonds Léon Fredericq (University of Liège), the Interuniversity Attraction Poles Programme-Belgian Science Policy (all from Belgium) and the Plan National Cancer (« Service Public Federal » from Belgium). Research in the lab of A.R.Q. and M.A.M. was supported by grants BIO2014-56092-R (MINECO and FEDER) and P12-CTS-1507 (Andalusian Government and FEDER)

Immunomodulatory properties of the lymphatic endothelium in the tumor microenvironment

The tumor microenvironment (TME) is an intricate complex and dynamic structure composed of various cell types, including tumor, stromal and immune cells. Within this complex network, lymphatic endothelial cells (LECs) play a crucial role in regulating immune responses and influencing tumor progression and metastatic dissemination to lymph node and distant organs. Interestingly, LECs possess unique immunomodulatory properties that can either promote or inhibit anti-tumor immune responses. In fact, tumor-associated lymphangiogenesis can facilitate tumor cell dissemination and metastasis supporting immunoevasion, but also, different molecular mechanisms involved in LEC-mediated anti-tumor immunity have been already described. In this context, the crosstalk between cancer cells, LECs and immune cells and how this communication can shape the immune landscape in the TME is gaining increased interest in recent years. In this review, we present a comprehensive and updated report about the immunomodulatory properties of the lymphatic endothelium within the TME, with special focus on primary tumors and tumor-draining lymph nodes. Furthermore, we outline emerging research investigating the potential therapeutic strategies targeting the lymphatic endothelium to enhance anti-tumor immune responses. Understanding the intricate mechanisms involved in LEC-mediated immune modulation in the TME opens up new possibilities for the development of innovative approaches to fight cancer

A course-based undergraduate research experience to illustrate the early stages of the drug discovery process

We have implemented at the University of Málaga (Spain) a new course-based undergraduate research experience (CURE) to involve undergraduate students of Science in a real-world scientific problem. Within the topic “Let's find acetylcholinesterase inhibitors as new drug candidates for the treatment of Alzheimer's”, students have been engaged into the early stages of the drug discovery process. Working in groups of 4–5 persons, they have searched information in databases, proposed solutions to the driving question and designed protocols to carry them out in vitro and in silico. Overall, the implementation of this experience has been very satisfactory in terms of academic performance and students' perception. This article reports a session from the virtual international 2021 IUBMB/ASBMB workshop, “Teaching Science on Big Data”.This work was supported by the University of Málaga (Spain) funds granted to the educational innovation projects PIE19-086. Open access funded by Universidad de Málaga/CBUA

AD0157, a pyrrolidinedione fungal metabolite, inhibits angiogenesis by targeting the Akt signaling pathway

In the course of a screening program for the inhibitors of angiogenesis from marine sources, AD0157, a pyrrolidinedione fungal metabolite, was selected for its angiosupressive properties. AD0157 inhibited the growth of endothelial and tumor cells in culture in the micromolar range. Our results show that subtoxic doses of this compound inhibit certain functions of endothelial cells, namely, differentiation, migration and proteolytic capability. Inhibition of the mentioned essential steps of in vitro angiogenesis is in agreement with the observed antiangiogenic activity, substantiated by using two in vivo angiogenesis models, the chorioallantoic membrane and the zebrafish embryo neovascularization assays, and by the ex vivo mouse aortic ring assay. Our data indicate that AD0157 induces apoptosis in endothelial cells through chromatin condensation, DNA fragmentation, increases in the subG1 peak and caspase activation. The data shown here altogether indicate for the first time that AD0157 displays antiangiogenic effects, both in vitro and in vivo, that are exerted partly by targeting the Akt signaling pathway in activated endothelial cells. The fact that these effects are carried out at lower concentrations than those required for other inhibitors of angiogenesis makes AD0157 a new promising drug candidate for further evaluation in the treatment of cancer and other angiogenesis-related pathologies. [Our experimental work is supported by grant P12-CTS-1507 (Andalusian Government and FEDER) and funds from group BIO-267 (Andalusian Government). The "CIBER de Enfermedades Raras" is an initiative from the ISCIII (Spain). This communication has the support of a travel grant "Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech"].Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Bringing Light to Science Undergraduate Students: A Successful Laboratory Experiment Illustrating the Principles and Applications of Bioluminescence

Although many laboratory experiments are available to illustrate spectrophotometric or fluorometric methods, few of them introduce the use of luminometry to students. Bioluminescence, a subtype of chemiluminescence, is produced when an enzyme-catalyzed chemical reaction gives rise to light emission. Despite the advantages of bioluminescent methods, including sensitivity and specificity, and their increasing use in experimental sciences and biomedical laboratories, their presence in courses is almost nonexistent. The luciferase-catalyzed enzymatic reaction has generated a myriad of practical applications, including those derived from the measurement of the ATP consumed in the reaction. In particular, the measurement of ATP levels in drinking or stored waters directly correlates with their bacteria content, facilitating the development of rapid methods for detecting bacterial contamination. This avoids the long waiting time associated with traditional microbiological methods, based on the growth of the microorganisms in a suitable culture medium. Over the past two years at the University of Malaga, we have implemented a new laboratory experiment for undergraduate chemistry and biochemistry students. In this experiment, students detected bacterial contamination in water by quantifying ATP with the luciferase-catalyzed reaction. The experiment was successfully implemented in two different formats, either as a full project developed by students throughout the entire duration of the academic course, or as a short protocol, carried out in a single laboratory session. Between them, a whole range of intermediate options could be arranged by educators to suit their course requirements and the learning objectives to be achieved by students.This work was supported by the University of Malaga (Spain) funds granted to the educational innovation projects PIE19-086 and PIE19-057, and the Spanish Ministry of Science, Innovation and Universities Grant EDU2017-82197-P

Antioxidant potential of an anthraquinone metabolite isolated from a marine fungus.

Marine ecosystem is a fruitful source of many pharmacologically active. In particular, a number of marine anthraquinones and their derivatives, have been studied for their potential as anticancer and antimetastatic agents, although little is known about their antiangiogenic activities. In addition, there is some controversy regarding the poor antioxidant effect of these marine secondary metabolites. In this study, we describe for the first time the antiangiogenic activity of an anthraquinone, isolated from a marine fungus, which was evidenced in vitro by the inhibition of the activated endothelial cells survival, proliferation, and differentiation into tubelike structures. Furthermore, we have demonstrated its protective effect against reactive oxygen species (ROS), especially in presence of hydrogen peroxide, a potent prooxidant agent. These results were evidenced by a reduced ROS production and an increased redox capacity of cells after treatment with this anthraquinone, evidenced through the staining with DCFHDA and the sulfhydryl groups determination, respectively. The observation that this compound appears to present a more potent effect in tumor than in endothelial cells, suggests a putative selectivity. All these results highlight the need for further study of this molecule as a potential therapeutic agent for cancer and other angiogenesisdependent diseases.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Antiangiogenic potential of an anthraquinone metabolite isolated from a marine fungus.

This is a communication in the format of a posterThe potential of marine organisms to yield bioactive molecules is vast and largely unexplored. Significantly, certain bioactive compounds derived from the marine environment have already received approval as anticancer drugs1. Among the multitude of bioactive compounds found in marine organisms, anthraquinones represent a notable class of molecules, with over 200 structurally related compounds having been isolated from diverse species of marine fungi2. Danthron (1,8-dihydroxy-9,10-anthraquinone) serves as an exemplary member of anthraquinones, possessing anti-tumoral and anti-angiogenic properties that have yet to be fully elucidated. Therefore, the primary objective of this study was to comprehensively investigate and understand these specific properties.Funding: Funding: Projects PID2019-105010RB-I00 (Ministry of Science and Innovation, Government of Spain), UMA18-FEDERJA-220 and P20_00257 (Junta de Andalucía-FEDER) The assistance to the congress has an help from the Plan Propio de Investigación (UMA). Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Modeling pre-metastatic lymphvascular niche in the mouse ear sponge assay.

Lymphangiogenesis, the formation of new lymphatic vessels, occurs in primary tumors and in draining lymph nodes leading to pre-metastatic niche formation. Reliable in vivo models are becoming instrumental for investigating alterations occurring in lymph nodes before tumor cell arrival. In this study, we demonstrate that B16F10 melanoma cell encapsulation in a biomaterial, and implantation in the mouse ear, prevents their rapid lymphatic spread observed when cells are directly injected in the ear. Vascular remodeling in lymph nodes was detected two weeks after sponge implantation, while their colonization by tumor cells occurred two weeks later. In this model, a huge lymphangiogenic response was induced in primary tumors and in pre-metastatic and metastatic lymph nodes. In control lymph nodes, lymphatic vessels were confined to the cortex. In contrast, an enlargement and expansion of lymphatic vessels towards paracortical and medullar areas occurred in pre-metastatic lymph nodes. We designed an original computerized-assisted quantification method to examine the lymphatic vessel structure and the spatial distribution. This new reliable and accurate model is suitable for in vivo studies of lymphangiogenesis, holds promise for unraveling the mechanisms underlying lymphatic metastases and pre-metastatic niche formation in lymph nodes, and will provide new tools for drug testing