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Autophagy, a catabolic process orchestrating the degradation of proteins and organelles within lysosomes, is pivotal for maintaining cellular homeostasis. However, its dual role in cancer involves preventing malignant transformation while fostering progression and therapy resistance. Vacuole Membrane Protein 1 (VMP1) is an essential autophagic protein whose expression, per se, triggers autophagy, being present in the whole autophagic flux. In pancreatic cancer, VMP1-whose expression is linked to the Kirsten Rat Sarcoma Virus (KRAS) oncogene-significantly contributes to disease promotion, progression, and chemotherapy resistance. This investigation extends to breast cancer, colon cancer, hepatocellular carcinoma, and more, highlighting VMP1's nuanced nature, contingent on specific tissue contexts. The examination of VMP1's interactions with micro-ribonucleic acids (miRNAs), including miR-21, miR-210, and miR-124, enhances our understanding of its regulatory network in cancer. Additionally, this article discusses VMP1 gene fusions, especially with ribosomal protein S6 kinase B1 (RPS6KB1), shedding light on potential implications for tumor malignancy. By deciphering the molecular mechanisms linking VMP1 to cancer progression, this exploration paves the way for innovative therapeutic strategies to disrupt these pathways and potentially improve treatment outcomes.

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Autophagy is a tightly regulated catabolic process involved in the degradation and recycling of proteins and organelles. Ubiquitination plays an important role in the regulation of autophagy. Vacuole Membrane Protein 1 (VMP1) is an essential autophagy protein. The expression of VMP1 in pancreatic cancer stem cells carrying the activated Kirsten rat sarcoma viral oncogene homolog (KRAS) triggers autophagy and enables therapy resistance. Using biochemical and cellular approaches, we identified ubiquitination as a post-translational modification of VMP1 from the initial steps in autophagosome biogenesis. VMP1 remains ubiquitinated as part of the autophagosome membrane throughout autophagic flux until autolysosome formation. However, VMP1 is not degraded by autophagy, nor by the ubiquitin-proteasomal system. Mass spectrometry and immunoprecipitation showed that the cell division cycle protein cdt2 (Cdt2), the substrate recognition subunit of the E3 ligase complex associated with cancer, cullin-RING ubiquitin ligase complex 4 (CRL4), is a novel interactor of VMP1 and is involved in VMP1 ubiquitination. VMP1 ubiquitination decreases under the CRL inhibitor MLN4924 and increases with Cdt2 overexpression. Moreover, VMP1 recruitment and autophagosome formation is significantly affected by CRL inhibition. Our results indicate that ubiquitination is a novel post-translational modification of VMP1 during autophagy in human tumor cells. VMP1 ubiquitination may be of clinical relevance in tumor-cell-therapy resistance.

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The coronavirus disease pandemic, which profoundly reshaped the world in 2019 (COVID-19), and is currently ongoing, has affected over 200 countries, caused over 500 million cumulative cases, and claimed the lives of over 6.4 million people worldwide as of August 2022. The causative agent is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Depicting this virus' life cycle and pathogenic mechanisms, as well as the cellular host factors and pathways involved during infection, has great relevance for the development of therapeutic strategies. Autophagy is a catabolic process that sequesters damaged cell organelles, proteins, and external invading microbes, and delivers them to the lysosomes for degradation. Autophagy would be involved in the entry, endo, and release, as well as the transcription and translation, of the viral particles in the host cell. Secretory autophagy would also be involved in developing the thrombotic immune-inflammatory syndrome seen in a significant number of COVID-19 patients that can lead to severe illness and even death. This review aims to review the main aspects that characterize the complex and not yet fully elucidated relationship between SARS-CoV-2 infection and autophagy. It briefly describes the key concepts regarding autophagy and mentions its pro- and antiviral roles, while also noting the reciprocal effect of viral infection in autophagic pathways and their clinical aspects.

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OBJECTIVES: Stroke epidemiology varies among different populations. The burden of stroke is high in low- and middle-income countries. Reliable population data is needed to assess the impact of stroke and to develop policies aimed to improve stroke care in our region. EstEPA is a population-based project assessing prevalence, incidence, mortality and burden of stroke in General Villegas Department, Buenos Aires, Argentina (pop=30,864 inhabitants). We determined incidence of stroke (first-ever and recurrent stroke) and stroke case-fatality rate from 2017 to 2020. METHODS: First-ever strokes, recurrent strokes and transient ischemic attacks were ascertained and case-fatality rate was obtained. Diagnoses were based on standard AHA/WHO definitions. Study population included all persons residing in General Villegas during the three-year period. Hospitals, households, nursing homes, death certificates and several overlapping sources were surveyed. RESULTS: We assessed 92,592 person-years. There were 155 cerebrovascular events aged 70 years (SD ± 13 years), of which 115 were first-ever strokes (74%), 21 recurrent strokes (13.5%) and 19 transient ischemic attacks (12.5%). The crude overall incidence rate of first-ever strokes was 124.2 per 100,000 population (86.9 per 100,000 [95% CI 58.5-115.2] when standardized by WHO World population and 109.7 per 100,000 [95% CI 89.7-129.8] when standardized by Argentine population) and 317.0 per 100,000 population in subjects older than 40 years. Case fatality rate at 30 days of first-ever strokes was 27%. CONCLUSION: In this population-based comprehensive stroke epidemiological study in Argentina, first-ever stroke incidence in an urban population was 124.2 per 100,000 population (86.9 per 100,000 adjusted by the WHO World population). This is lower than the incidence in other countries in the region and similar to a recent incidence study in Argentina. It is also comparable to reported incidence in most middle- and high-income countries. Stroke case-fatality rate was comparable to other population-based Latin-American studies.

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Hemax® is an epoetin alfa product developed by Biosidus S.A. in Argentina at the end of the 1980s and has been present in that market since 1991. The initial presentation was a lyophilized powder containing albumin as stabilizer, to best adapt to environmental conditions in developing countries; more recently, a prefilled syringe, albumin-free presentation was developed, since this presentation has become the preferred standard in many markets. The primary objective was to compare the pharmacokinetic profile of different formulations of epoetin alfa after a single subcutaneous administration to healthy volunteers of 40 000 IU of Eprex/Erypo® and Hemax® PFS. This clinical trial was conceived following an open-label, randomized, three-way three-period cross-over balanced, and sequential design. The study was conducted on 24 healthy volunteers. To analyze similarity between Hemax® PFS and the innovator product, Eprex®, area under the curve (AUC) and Cmax of both products have been compared. The 90% CI lower limit for the geometric mean ratios was higher than 80% for any comparisons, and the 90% CI upper limit for these geometric ratios was below 125% for all the comparisons made, thus demonstrating equivalence between both products. The comparison between Hemax® PFS and Eprex® resulted in similar 90% CI for Cmax , AUC(0-120 h) and AUC(0-inf) ratios, all of them within the 80-125% interval, with a power above 95% for each ratio. These findings suggest biosimilar patterns for absorption velocity (with Tmax close to 15 h), absorption extent, and elimination (with an elimination half-life close to 25-30 h for each formulation).

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BACKGROUND: Hepcidin is a protein that regulates the metabolism of iron. In addition, a high iron load can cause insulin resistance and subsequent diabetes. OBJECTIVE: To investigate the association between hepcidin levels and glucose, insulin, lipids, HOMA-IR, and inflammatory markers, C reactive protein (CRP), ferritin, Lp (a), and leucocytes, in indigenous school children living at 4000 m above sea level. Data were collected cross-sectionally from the four schools in San Antonio de los Cobres (SAC). BMI, glucose, insulin, lipids, CRP, hemoglobin, leucocytes, iron, ferritin, transferrin, and hepcidin levels were obtained. RESULTS: Three hundred and seventy-six children (170 males) aged 9.6 ± 2.3 y were included. Fifty-five(15.2 %) children were underweight, 28 (7.4 %) overweight and 10 (2.7 %) obese. Univariate analysis showed a significant inverse correlation between hepcidin and glucose (r = -0.14) and HOMA-IR (r = -0.30). Furthermore, hepcidin was found to be directly and significantly correlated with Lp(a) (r = 0.18), leucocytes (r = 0.24,) CRP (r = 0.32), and ferritin (r = 0.32). Multiple linear regression analysis indicated that hepcidin was significantly and inversely associated with glucose and BMI and directly with Lp(a), CRP, leucocytes, and ferritin; adjusted for age and gender (R2 0.26). CONCLUSION: In this study, which included indigenous children living at high altitudes (4000 m), hepcidin was significantly and inversely associated with glucose and BMI and directly associated with inflammatory markers such as CRP, Lp(a), leucocytes, and ferritin, suggesting that hepcidin could be a reliable marker of future type 2 diabetes.

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Objective: To determine if the triglycerides and glucose index (TyG) can be used as a marker for insulin resistance (IR) in Argentinean schoolchildren according to age and sex. Methods: Anthropometric data, blood glucose levels, lipid profiles, and insulin levels were measured. The TyG index was defined by Ln [fasting triglyceride (mg/dL)* fasting glucose (mg/dL)/2]. A comparison of the ability of TyG to identify children with IR was performed using receiver operating characteristic (ROC) curves and the area under the ROC (AUROC) curve. IR was defined as HOMA-IR > III quartile. Results: A total of 915 (528, 57.7% males) apparently healthy schoolchildren, aged 9.3 ± 2.2, were evaluated. The AUROC using the HOMA-IR > III quartile as the dichotomous variable showed that TyG was a fair marker to identify IR (0.65, 95% CI, 0.61-0.69; p < 0.01). There was a significantly higher TyG AUROC in males (0.69, 95% CI, 0.63-0.75; p < 001) than in females (0.60, 95% CI, 0.54-0.66; p < 0.01). When children were divided according to age into two groups (5.0-9.9 and 10.0-14.9-year-olds); younger children (0.64, 95% CI, 0.58-0.69; p < 0.011) and older children (0.62, 95% CI, 0.55-0.68; p = 0.01) had a similar and fair AUROC. However, when children were divided by age and sex, females older than ten had a non-significant AUROC (0.53, 95% CI, 0.42-0.63; p = 0.61). The TyG index compared with HOMA-IR had low sensitivity and specificity, ranging from 0.62 to 0.56. Conclusion: The TyG index had a fair AUROC with low sensitivity and specificity, indicating poor discrimination in identifying IR in apparently healthy Argentinean children. The ability to use TyG for screening purposes seems limited in Argentinean schoolchildren.

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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.

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BACKGROUND: The association between central obesity and cardiometabolic complications justifies exploring its association in normal-weight and overweight/obese (OW/OB) schoolchildren. OBJECTIVE: To describe cardiometabolic markers in four groups according to BMI/WC categories: (i) normal weight with central OB; (ii) normal weight without central OB; (iii) OW/OB with central OB and (iv) OW/OB without central OB, in a sample of Argentinean schoolchildren. METHODS: A cross-sectional study of 1264 Argentinean schoolchildren (624 F), aged 9.5 ± 2.2 years was performed between November 2013 and 2015. Children's anthropometric measures, blood pressure (BP), glucose, lipids, and insulin were measured. Children were divided into four groups: (i) normal weight with central OB; (ii) normal weight without central OB; (iii) OW/OB with central OB and (iv) OW/OB without central OB. RESULTS: The prevalence of normal-weight children without central OB was 64.3% (796), normal weight with central OB 5% (66), OW/OB without central OB 11% (137), and OW/OB with central OB 21% (265). Normal weight with central OB had significantly higher triglycerides than normal-weight children without central OB (86 vs 70 mg/dL, respectively) and OW/OB children without central OB (81 vs 77 mg/dL). Multiple linear regression analyses showed that age, systolic BP, HDL-C, triglycerides, and maternal WC were significantly associated with children's WC; R2 = 0.50 as well as children's BMI; R2 = 0.37. CONCLUSION: This study found that children with central OB might be at future higher cardiometabolic risk than those without central OB independently of the presence of OW/OB. However, future longitudinal studies should be performed to confirm these findings.