Autophagy, physiology and cell pathology

Autophagy plays an important role in human pathologies, such as myopathies and neurodegenerative diseases. Moreover, metabolic disease processes such as diabetes and pancreatitis, as well as tumor cells and cancer chemotherapy, activate autophagy. Furthermore, a selective type of autophagy of pancreatic zymogen granules has been discovered and characterized as a protective cellular process triggered by acute pancreatitis. In this review we describe the physiological bases and molecular mechanisms in the autophagic process and the possible role of autophagy in human disease. Understanding the events and molecular mechanisms of this complex cellular process will help in the design of new strategies for more effective diagnosis and treatment.Fil: Vaccaro, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; Argentin

Beclin 1

Beclin 1/ATG6/Vps30 (UniProtKB/Swiss-Prot Q14457) is a 450 amino-acids length protein, with three domains; BH3 (aminoacid 114 to 123), Coiled Coil domain (CCD; aminoacid 144 to 269) and the Evolutionarily Conserved Domain (ECD; aminoacid 244 to 337). BH3 proteins are part of the Bcl-2 family; they are pro-apoptotic damage sensors that play an important role in protecting against cancer (1). The BH3-only domain of Beclin 1 can interact with Bcl-2 and Bcl-XL (2;3). Both cellular and viral Bcl-2 (vBcl-2), or more specifically ER-targeted Bcl-2, inhibit Beclin 1-dependent autophagy by interfering with the Beclin 1-PtdIns 3-kinase interaction (PI3K) and the Beclin 1-associated PI3K activity (3,4). The interaction between Bcl-2 and Beclin 1 is greatly reduced upon starvation, which suggests that the dissociation of Bcl-2 from Beclin1 is important for activating autophagy. We demonstrated that, VMP1 (Vacuole Membrane Protein 1) displaces Bcl-2 from Beclin 1, partitioning Beclin 1 to the autophagic pathway (Molejon et al., Sci Rep. 2012; In press).Fil: Molejon, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; ArgentinaFil: Ropolo, Alejandro Javier. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; ArgentinaFil: Vaccaro, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; Argentin

Translational Pancreatology. New Approaches in the Development of Novel Biomarkers as Screening Methodologies for Pancreatic Cancer

Pancreatic Ductal Adenocarcinoma (PDAC) is one of the rare cancers for which no significant improvements in diagnosis and therapy have been made in the last 30 years. Despite considerable progress the median survival of most patients is 5 to 6 months. Currently, 80% of patients diagnosed with pancreatic adenocarcinoma present with locally invasive and/or metastatic disease, resulting in a poor 5-year survival of <5%. Hence, less than 20% of patients with PDAC undergo potentially curative surgery, whereas the remaining patients, can only be offered palliative treatment. Only 15–20% of patients undergo resection. The development of a diagnostic tool for early detection of patients with this malignancy may significantly impact their prognosis. Pancreatic cancer has a strong correlation between tumor stage and prognosis. The size of the tumors is also important in a general sense, the smaller ones have metastases less frequently than the larger ones at the time of diagnosis and, therefore, are more likely to be cured by surgery. Therefore, it is evident that the earliest detection of cancers is one of the keys to reducing deaths from these diseases and this includes the cancer of the pancreas with its high mortality rates. However, effective early diagnosis remains difficult and depends mainly on imaging modalities and the development of screening methodologies with highly sensitive and specific biomarkers. This review summarizes recent advances in effective screening for early diagnosis of PDAC using novel molecular biomarkers discovered from various studies including protein biomarkers, mutant DNA templates identified in the circulation in blood samples (ctDNA), DNA promoter hypermethylation and measurement of microRNA as other possible noninvasive biomarker for early detection of Pancreatic Cancer. These data have high translational relevance and suggest that early detection is the key issue for improving the prognosis of this aggressive disease. Although many biomarkers for early detection of Pancreatic Cancer (PC) have been discovered through various methods, effective panels of noninvasive biomarkers for screening and early detection of Pancreatic Ductal Adenocarcinoma (PDAC) are not available yet. The increased number of translational studies would be able to provide this remarkable diagnostic tool in a near future. Nevertheless, larger scale and rigorous validation is required before their application in the clinic. ofPDAC using novel molecular biomarkers discovered from various studies including proteinbiomarkers, mutant DNA templates identified in the circulation in blood samples (ctDNA),DNA promoter hypermethylation and measurement of microRNA as other possiblenoninvasive biomarker for early detection of Pancreatic Cancer.These data have high translational relevance and suggest that early detection is the keyissue for improving the prognosis of this aggressive disease. Although many biomarkers forearly detection of Pancreatic Cancer (PC) have been discovered through various methods,effective panels of noninvasive biomarkers for screening and early detection of PancreaticDuctal Adenocarcinoma (PDAC) are not available yet.The increased number of translational studies would be able to provide this remarkablediagnostic tool in a near future. Nevertheless,Fil: Vaccaro, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Resnik, Roxana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; Argentin

Macroautophagy and the oncogene-induced senescence

The oncogene-induced senescence is emerging as a potent tumor suppressor mechanism and as a possible therapeutic target. Macroautophagy is intimately linked to the senescence condition setup, although its role has not been elucidated yet. Here, we discuss up-to-date concepts of senescence-related macroautophagy and evaluate the current trend of this growing research field, which has relevance in future perspectives toward therapeutic options against cancer.Fil: Grasso, Daniel Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Vaccaro, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Bioquímica y Medicina Molecular; Argentin

Glycoconjugation: An approach to cancer therapeutics

Cancer constitutes the second leading cause of death globally and is consideredto have been responsible for an estimated 9.6 million fatalities in 2018. Although treatments against gastrointestinal tumors have recently advanced, those interventions can only be applied to a minority of patients at the time ofdiagnosis. Therefore, new therapeutic options are necessary for advanced stagesof the disease. Glycosylation of antitumor agents, has been found to improvepharmacokinetic parameters, reduce side effects, and expand drug half-life incomparison with the parent compounds. In addition, glycosylation of therapeuticagents has been proven to be an effective strategy for their targeting tumor tissue, thereby reducing the doses of the glycodrugs administered to patients. This review focusses on the effect of the targeting properties of glycosylated antitumor agents on gastrointestinal tumors.Fil: Molejon, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Weiz, Gisela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Breccia, Javier Dario. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Vaccaro, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; Argentin

The VMP1-Beclin 1 interaction regulates autophagy induction

Fil: Molejon, Maria Ines. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; Argentina;Fil: Ropolo, Alejandro Javier. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; Argentina;Fil: Lo Ré, Andrea Emilia. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; Argentina;Fil: Boggio, Veronica Ines. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; Argentina;Fil: Vaccaro, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; Argentina

Secretory Autophagy and Its Relevance in Metabolic and Degenerative Disease

Proteins to be secreted through so-called “conventional mechanisms” are characterized by the presence of an N-terminal peptide that is a leader or signal peptide, needed for access to the endoplasmic reticulum and the Golgi apparatus for further secretion. However, some relevant cytosolic proteins lack of this signal peptides and should be secreted by different unconventional or “non-canonical” processes. One form of this unconventional secretion was named secretory autophagy (SA) because it is specifically associated with the autophagy pathway. It is defined by ATG proteins that regulate the biogenesis of the autophagosome, its representative organelle. The canonical macroautophagy involves the fusion of the autophagosomes with lysosomes for content degradation, whereas the SA pathway bypasses this degradative process to allow the secretion. ATG5, as well as other factors involved in autophagy such as BCN1, are also activated as part of the secretory pathway. SA has been recognized as a new mechanism that is becoming of increasing relevance to explain the unconventional secretion of a series of cytosolic proteins that have critical biological importance. Also, SA may play a role in the release of aggregation-prone protein since it has been related to the autophagosome biogenesis machinery. SA requires the autophagic pathway and both, secretory autophagy and canonical degradative autophagy are at the same time, integrated and highly regulated processes that interact in ultimate cross-talking molecular mechanisms. The potential implications of alterations in SA, its cargos, pathways, and regulation in human diseases such as metabolic/aging pathological processes are predictable. Further research of SA as potential target of therapeutic intervention is deserved.Fil: González, Claudio Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Resnik, Roxana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Vaccaro, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; Argentin

Efecto antitumoral de compuestos glicoconjugados sobre cultivos primarios de células de cáncer de páncreas obtenidas por ecoendoscopía

El adenocarcinoma pancreático (PDAC), que constituye el 90% de los cánceres de páncreas, es la cuarta causa mundial de muertes relacionadas al cáncer. Debido a sus características moleculares y genéticas, PDAC pertenece al grupo de tumores con más resistencia al tratamiento quimioterápico. En la actualidad, las opciones terapéuticas disponibles incluyen la cirugía, la radiación, la quimioterapia, la inmunoterapia y drogas dirigidas. Sin embargo, la mayoría de los tratamientos son paliativos, con el objeto de disminuir los síntomas relacionados con la enfermedad. Por lo tanto, nuestro objetivo es evaluar el efecto de un compuesto glicosilado, la hidroquinona-rutinósido, sobre células tumorales pancreáticas primarias con el fin de buscar mayor efectividad de los tratamientos quimioterápicos actuales. Encontramos que la utilización de glicocompuestos como segunda línea de terapia mejora significativamente el efecto antitumoral de la gemcitabina. Estos resultados sugieren un potencial interés en la utilización de compuestos glicoconjugados como terapias complementarias a los tratamientos estándares contra el cáncer.Pancreatic ductal adenocarcinoma (PDAC), which constitutes 90% of pancreatic cancers, is the fourth leading cause of cancer-related deaths in the world. PDAC belongs to one of the most chemo resistant cancers, in part due to its molecularand genetics features. Currently, available therapeutic options are surgery, radiation, chemotherapy, and immunotherapy. Most of the available treatments are palliative, with the objective of relieving disease-related symptoms. Our aim was to evaluate the antitumoral effect as a second line therapy, of enzymatically glycosylated compounds, hydroquinone-rutinoside, on primary pancreatic tumoral cells. We found that glycoconjugates combined with antitumor agents, such as gemcitabine, improved single-treatment effects. These findings suggest that emerging trends towards glycoconjugates could be a promising approach for cancer therapies.Fil: Molejon, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Weiz, Gisela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Tellechea, Juan Ignacio. Institución Médica Profensa; ArgentinaFil: Breccia, Javier Dario. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Vaccaro, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; Argentin

Autophagy dysregulation in diabetic kidney disease: From pathophysiology to pharmacological interventions

Diabetic kidney disease (DKD) is a frequent, potentially devastating complication of diabetes mellitus. Several factors are involved in its pathophysiology. At a cellular level, diabetic kidney disease is associated with many structural and functional alterations. Autophagy is a cellular mechanism that transports intracytoplasmic components to lysosomes to preserve cellular function and homeostasis. Autophagy integrity is essential for cell homeostasis, its alteration can drive to cell damage or death. Diabetic kidney disease is associated with profound autophagy dysregulation. Autophagy rate and flux alterations were described in several models of diabetic kidney disease. Some of them are closely linked with disease progression and severity. Some antidiabetic agents have shown significant effects on autophagy. A few of them have also demonstrated to modify disease progression and improved outcomes in affected patients. Other drugs also target autophagy and are being explored for clinical use in patients with diabetic kidney disease. The modulation of autophagy could be relevant for the pharmacological treatment and prevention of this disease in the future. Therefore, this is an evolving area that requires further experimental and clinical research. Here we discuss the relationship between autophagy and Diabetic kidney disease and the potential value of autophagy modulation as a target for pharmacological intervention.Fil: González, Claudio Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; Argentina. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Carro Negueruela, María Paula. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Santamarina, Catalina Nicora. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Resnik, Roxana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Vaccaro, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; Argentina. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; Argentin