Dehydroascorbic acid sensitizes cancer cells to system xc- inhibition-induced ferroptosis by promoting lipid droplet peroxidation.

Since the discovery of ferroptosis, it has been postulated that this type of cell death could be utilized in treatments for cancer. Unfortunately, several highly aggressive tumor models are resistant to the pharmacological induction of ferroptosis. However, with the use of combined therapies, it is possible to recover sensitivity to ferroptosis in certain cellular models. Here, we discovered that co-treatment with the metabolically stable ferroptosis inducer imidazole ketone erastin (IKE) and the oxidized form of vitamin C, dehydroascorbic acid (DHAA), is a powerful therapy that induces ferroptosis in tumor cells previously resistant to IKE-induced ferroptosis. We determined that DHAA and IKE + DHAA delocalize and deplete GPX4 in tumor cells, specifically inducing lipid droplet peroxidation, which leads to ferroptosis. Moreover, in vivo, IKE + DHAA has high efficacy with regard to the eradication of highly aggressive tumors such as glioblastomas. Thus, the use of IKE + DHAA could be an effective and safe therapy for the eradication of difficult-to-treat cancers.

Hyperglycemia increases SCO-spondin and Wnt5a secretion into the cerebrospinal fluid to regulate ependymal cell beating and glucose sensing.

Hyperglycemia increases glucose concentrations in the cerebrospinal fluid (CSF), activating glucose-sensing mechanisms and feeding behavior in the hypothalamus. Here, we discuss how hyperglycemia temporarily modifies ependymal cell ciliary beating to increase hypothalamic glucose sensing. A high level of glucose in the rat CSF stimulates glucose transporter 2 (GLUT2)-positive subcommissural organ (SCO) cells to release SCO-spondin into the dorsal third ventricle. Genetic inactivation of mice GLUT2 decreases hyperglycemia-induced SCO-spondin secretion. In addition, SCO cells secrete Wnt5a-positive vesicles; thus, Wnt5a and SCO-spondin are found at the apex of dorsal ependymal cilia to regulate ciliary beating. Frizzled-2 and ROR2 receptors, as well as specific proteoglycans, such as glypican/testican (essential for the interaction of Wnt5a with its receptors) and Cx43 coupling, were also analyzed in ependymal cells. Finally, we propose that the SCO-spondin/Wnt5a/Frizzled-2/Cx43 axis in ependymal cells regulates ciliary beating, a cyclic and adaptive signaling mechanism to control glucose sensing.

Role of Muscle Ultrasound for the Study of Frailty in Elderly Patients with Diabetes: A Pilot Study.

BACKGROUND: Sarcopenia and diabetes contribute to the development of frailty. Therefore, accessible methods, such as muscle ultrasounds (MUSs), to screen for sarcopenia should be implemented in clinical practice. METHODS: We conducted a cross-sectional pilot study including 47 patients with diabetes (mean age: 77.72 ± 5.08 years, mean weight: 75.8 kg ± 15.89 kg, and body mass index: 31.19 ± 6.65 kg/m2) categorized as frail by the FRAIL Scale or Clinical Frailty Scale and confirmed by Fried's Frailty Phenotype or Rockwood's 36-item Frailty Index. We used the SARC-F questionnaire to identify sarcopenia. The Short Physical Performance Battery (SPPB) and the Timed Up and Go (TUG) tests were used to assess physical performance and the risk of falls, respectively. In addition, other variables were measured: fat-free mass (FFM) and Sarcopenia Risk Index (SRI) with the bioimpedance analysis (BIA); thigh muscle thickness (TMT) of the quadriceps with MUS; and hand-grip strength with dynamometry. RESULTS: We observed correlations between the SARC-F and FFM (R = -0.4; p < 0.002) and hand-grip strength (R = -0.5; p < 0.0002), as well as between the TMT and FFM of the right leg (R = 0.4; p < 0.02) and the SRI (R = 0.6; p < 0.0001). We could predict sarcopenia using a logistic regression model with a ROC curve (AUC = 0.78) including FFM, handgrip strength, and TMT. The optimal cut-off point for maximum efficiency was 1.58 cm for TMT (sensitivity = 71.4% and specificity = 51.5%). However, we did not observe differences in the TMT among groups of greater/less frailty based on the SARC-F, SPPB, and TUG (p > 0.05). CONCLUSIONS: MUSs, which correlated with the BIA (R = 0.4; p < 0.02), complemented the diagnosis, identifying regional sarcopenia of the quadriceps in frail patients with diabetes and improving the ROC curve to AUC = 0.78. In addition, a TMT cut-off point for the diagnosis of sarcopenia of 1.58 cm was obtained. Larger studies to validate the MUS technique as a screening strategy are warranted.

The Medtronic 780G advanced hybrid closed-loop system achieves and maintains good glycaemic control in type 1 diabetes adults despite previous treatment.

INTRODUCTION: Improvements in continuous glucose monitoring (CGM) in recent years have changed the treatment of type 1 diabetes (T1D) by permitting the automation of glucose control. The Minimed 780G advanced hybrid closed-loop (ACHL) system adapts basal infusion rates and delivers auto-correction boluses in order to achieve a user-decided glucose target (100, 110 or 120mg/dL). This study set out to evaluate the effectiveness of the Medtronic 780G system in real-life conditions over 6 months. MATERIALS AND METHODS: Prospective study that included T1D subjects previously treated with insulin pump without CGM (pump group) or with sensor-augmented pump with predictive low-glucose suspend (SAP-PLGS group) who started with the Minimed 780G system. Sensor and pump data from baseline, and at 1, 3 and 6 months were downloaded and HbA1c was recorded at baseline and at 6 months. RESULTS: Fifty T1D subjects were included; 25 were previous SAP-PLGS 640G users and 25 used 640G without CGM. 66% were female, 48.6 (40-57) years of age with 20 (12-31.5) years of diabetes duration. Time in range (TIR) improved in the total cohort from baseline to 6 months (69% (57.7-76) vs. 74% (70-82); p=0.01 as did HbA1c (7.6% (7.1-7.8) vs. 7.0% (6.8-7.5); p<0.001), with improvement in times <54, >180 and >250mg/dL. Outcomes at 6 months did not differ between groups, although the SAP-PLGS subjects were prone to hypoglycaemia and the pump group mainly presented suboptimal metabolic control. CONCLUSION: The AHCL Medtronic Minimed 780G system achieves and maintains good glycaemic control over 6 months in real-life conditions in different profiles of T1D subjects.

Role of Excessive Weight Gain During Gestation in the Risk of ADHD in Offspring of Women With Gestational Diabetes.

CONTEXT: Although attention-deficit/hyperactivity disorder (ADHD) has been associated with gestational diabetes mellitus (GDM) and maternal obesity, excessive weight gain (EWG) during pregnancy has scarcely been evaluated. OBJECTIVE: This study aimed to assess the joint effect of maternal weight and EWG on the risk of ADHD in offspring of GDM pregnancies. METHODS: In this cohort study of singleton births >22 weeks of gestation of women with GDM between 1991 and 2008, gestational weight gain above the National Academy of Medicine (NAM) recommendations was classified into EWG. Cox-regression models estimated the effect of maternal pregestational weight and EWG on the risk of ADHD (identified from medical records), adjusted for pregnancy outcomes and GDM-related variables. RESULTS: Of 1036 children who were included, with a median follow-up of 17.7 years, 135 (13%) were diagnosed with ADHD. ADHD rates according to pregestational maternal weight were 1/14 (7.1%) for underweight, 62/546 (11.4%) for normal weight, 40/281 (14.2%) for overweight, and 32/195 (16.4%) for obesity. Only maternal obesity was independently associated with ADHD (HRadjusted 1.66 [95% CI, 1.07-2.60]), but not maternal overweight or EWG. On evaluating the joint contribution of maternal weight and EWG, maternal obesity with EWG was associated with the highest risk of ADHD (vs normal weight without EWG; HRadjusted 2.13 [95% CI, 1.14-4.01]). Pregestational obesity without EWG was no longer associated (HRadjusted 1.36 [95% CI, 0.78-2.36]). CONCLUSION: Among GDM pregnancies, pregestational obesity was associated with a higher risk of ADHD in offspring. Nonetheless, when gestational weight gain was taken into account, only the joint association of obesity and EWG remained significant.

Pharmacological targets for the induction of ferroptosis: Focus on Neuroblastoma and Glioblastoma.

Neuroblastomas are the main extracranial tumors that affect children, while glioblastomas are the most lethal brain tumors, with a median survival time of less than 12 months, and the prognosis of these tumors is poor due to multidrug resistance. Thus, the development of new therapies for the treatment of these types of tumors is urgently needed. In this context, a new type of cell death with strong antitumor potential, called ferroptosis, has recently been described. Ferroptosis is molecularly, morphologically and biochemically different from the other types of cell death described to date because it continues in the absence of classical effectors of apoptosis and does not require the necroptotic machinery. In contrast, ferroptosis has been defined as an iron-dependent form of cell death that is inhibited by glutathione peroxidase 4 (GPX4) activity. Interestingly, ferroptosis can be induced pharmacologically, with potential antitumor activity in vivo and eventual application prospects in translational medicine. Here, we summarize the main pathways of pharmacological ferroptosis induction in tumor cells known to date, along with the limitations of, perspectives on and possible applications of this in the treatment of these tumors.

Usefulness of Muscle Ultrasound to Study Sarcopenic Obesity: A Pilot Case-Control Study.

Background and objectives: Sarcopenic obesity (SO) is an emerging problem, especially in candidates for bariatric surgery (BS). We hypothesized that musculoskeletal ultrasound (MUS), a simple and accessible method, could be a reliable index of SO. Materials and Methods: A cross-sectional pilot study including 122 subjects (90 cases and 32 controls, 73% female, mean age: 51.2 years) who underwent BS was conducted at University Hospital Mútua Terrassa. The lean mass (LM) was calculated by bioelectrical impedance analysis (BIA) and the thigh muscle thickness (TMT) by MUS. To identify the subjects with SO by BIA, we used skeletal muscle index (SMI). The validity of MUS was determined using the ROC curve. Results: The mean BMI in the obesity group was 44.22 kg/m2. We observed a correlation between the LM and SMI assessed by BIA and the TMT assessed by MUS (R = 0.46, p < 0.001). This correlation was maintained at significant levels in the SO group (n = 40): R = 0.79; p = 0.003). The TMT assessed by MUS was able to predict SMI using BIA (AUC 0.77; 95% CI: 0.68242 to 0.84281). The optimal cut-off point for maximum efficiency was 1.57 cm in TMT (sensitivity = 75.6% and specificity = 71.1%). Conclusions: The TMT of the quadriceps assessed by US is a useful tool for identifying subjects with SO. Larger studies to validate this simple low-cost screening strategy are warranted.

Influence of Maternal Diabetes on the Risk of Neurodevelopmental Disorders in Offspring in the Prenatal and Postnatal Periods.

BACKGROUND: This study aimed to evaluate the influence of maternal diabetes in the risk of neurodevelopmental disorders in offspring in the prenatal and postnatal periods. METHODS: This cohort study included singleton gestational diabetes mellitus (GDM) pregnancies >22 weeks' gestation with live newborns between 1991 and 2008. The control group was randomly selected and matched (1:2) for maternal age, weeks of gestation and birth year. Cox regression models estimated the effect of GDM on the risk of attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and maternal type 2 diabetes mellitus (T2DM). Moreover, interaction between maternal T2DM and GDM-ADHD relationship was evaluated. RESULTS: Children (n=3,123) were included (1,073 GDM; 2,050 control group). The median follow-up was 18.2 years (interquartile range, 14.2 to 22.3) (n=323 with ADHD, n=36 with ASD, and n=275 from women who developed T2DM). GDM exposure was associated with ADHD (hazard ratio [HR]crude, 1.67; 95% confidence interval [CI], 1.33 to 2.07) (HRadjusted, 1.64; 95% CI, 1.31 to 2.05). This association remained significant regardless of the treatment (diet or insulin) and diagnosis after 26 weeks of gestation. Children of mothers who developed T2DM presented higher rates of ADHD (14.2 vs. 10%, P=0.029). However, no interaction was found when T2DM was included in the GDM and ADHD models (P>0.05). GDM was not associated with an increased risk of ASD (HRadjusted, 1.46; 95% CI, 0.74 to 2.84). CONCLUSION: Prenatal exposure to GDM increases the risk of ADHD in offspring, regardless of GDM treatment complexity. However, postnatal exposure to maternal T2DM was not related to the development of ADHD.

SVCT2 Overexpression and Ascorbic Acid Uptake Increase Cortical Neuron Differentiation, Which Is Dependent on Vitamin C Recycling between Neurons and Astrocytes.

During brain development, sodium-vitamin C transporter (SVCT2) has been detected primarily in radial glial cells in situ, with low-to-absent expression in cerebral cortex neuroblasts. However, strong SVCT2 expression is observed during the first postnatal days, resulting in increased intracellular concentration of vitamin C. Hippocampal neurons isolated from SVCT2 knockout mice showed shorter neurites and low clustering of glutamate receptors. Other studies have shown that vitamin C-deprived guinea pigs have reduced spatial memory, suggesting that ascorbic acid (AA) and SVCT2 have important roles in postnatal neuronal differentiation and neurite formation. In this study, SVCT2 lentiviral overexpression induced branching and increased synaptic proteins expression in primary cultures of cortical neurons. Analysis in neuroblastoma 2a (Neuro2a) and human subventricular tumor C3 (HSVT-C3) cells showed similar branching results. SVCT2 was mainly observed in the cell membrane and endoplasmic reticulum; however, it was not detected in the mitochondria. Cellular branching in neuronal cells and in a previously standardized neurosphere assay is dependent on the recycling of vitamin C or reduction in dehydroascorbic acid (DHA, produced by neurons) by glial cells. The effect of WZB117, a selective glucose/DHA transporter 1 (GLUT1) inhibitor expressed in glial cells, was also studied. By inhibiting GLUT1 glial cells, a loss of branching is observed in vitro, which is reproduced in the cerebral cortex in situ. We concluded that vitamin C recycling between neurons and astrocyte-like cells is fundamental to maintain neuronal differentiation in vitro and in vivo. The recycling activity begins at the cerebral postnatal cortex when neurons increase SVCT2 expression and concomitantly, GLUT1 is expressed in glial cells.

Two Distinct Faces of Vitamin C: AA vs. DHA.

Historically, vitamin C has been associated with many regulatory processes that involve specific signaling pathways. Among the most studied signaling pathways are those involved in the regulation of aging, differentiation, neurotransmission, proliferation, and cell death processes in cancer. This wide variety of regulatory effects is due to the fact that vitamin C has a dual mechanism of action. On the one hand, it regulates the expression of genes associated with proliferation (Ccnf and Ccnb1), differentiation (Sox-2 and Oct-4), and cell death (RIPK1 and Bcl-2). At the same time, vitamin C can act as a regulator of kinases, such as MAPK and p38, or by controlling the activation of the NF-kB pathway, generating chronic responses related to changes in gene expression or acute responses associated with the regulation of signal transduction processes. To date, data from the literature show a permanent increase in processes regulated by vitamin C. In this review, we critically examine how vitamin C regulates these different cellular programs in normal and tumor cells.

The SEEN comprehensive clinical survey of adult obesity: Executive summary. / Abordaje clínico integral SEEN de la obesidad en la edad adulta: resumen ejecutivo.

Obesity is one of the great challenges in healthcare nowadays with important implications for health so requiring comprehensive management. This document aims to establish practical and evidence-based recommendations for the diagnosis and management of in Spain, from the perspective of the clinical endocrinologist. A position statement has been made that can be consulted at www.seen.es, and that has been agreed by the Obesity Group of the Spanish Society of Endocrinology and Nutrition (GOSEEN), together with the Nutrition Area (NutriSEEN) and the Working Group of Endocrinology, Nutrition and Physical Exercise (GENEFSEEN).

Obesidad sarcopénica: un nuevo reto en la clínica práctica / Sarcopenic obesity: a new challenge in the clinical practice

La obesidad sarcopénica se ha asociado con mayor discapacidad y morbimortalidad. Sin embargo, todavía existen pocos estudios sobre el papel de la sarcopenia en las comorbilidades asociadas a la obesidad en individuos con edad inferior a 65 años. La etiopatogenia es multifactorial pero parece que los mediadores inflamatorios y la resistencia a la insulina desempeñan un papel relevante. Aunque no existe un consenso claro sobre su definición y métodos diagnósticos, hay un creciente interés por disponer de biomarcadores que ayuden a su detección y seguimiento. Respecto al tratamiento, se postula el abordaje multimodal, que básicamente se fundamenta en recomendaciones dietéticas, ejercicio y eventualmente cirugía bariátrica

Sarcopenic obesity has been associated with greater disability, morbidity and mortality. However, at present, there are few studies regarding the role of sarcopenia in the evolution of the comorbidities associated with obesity in individuals less than 65 years of age. The pathogenesis is multifactorial and uncompletely ilucidated, but it seems that inflammatory mediators and insulin resistance play an important role. Although there is no clear consensus on its definition and diagnostic methods, there is a growing interest in finding biomarkers useful for the detection and monitoring. Regarding the treatment, a multimodal approach is recomended, based on dietary recommendations, exercise and eventually bariatric surgery

Sarcopenic obesity: a new challenge in the clinical practice. / Obesidad sarcopénica: un nuevo reto en la clínica práctica.

Sarcopenic obesity has been associated with greater disability, morbidity and mortality. However, at present, there are few studies regarding the role of sarcopenia in the evolution of the comorbidities associated with obesity in individuals less than 65 years of age. The pathogenesis is multifactorial and uncompletely ilucidated, but it seems that inflammatory mediators and insulin resistance play an important role. Although there is no clear consensus on its definition and diagnostic methods, there is a growing interest in finding biomarkers useful for the detection and monitoring. Regarding the treatment, a multimodal approach is recomended, based on dietary recommendations, exercise and eventually bariatric surgery.

Vitamin C controls neuronal necroptosis under oxidative stress.

Under physiological conditions, vitamin C is the main antioxidant found in the central nervous system and is found in two states: reduced as ascorbic acid (AA) and oxidized as dehydroascorbic acid (DHA). However, under pathophysiological conditions, AA is oxidized to DHA. The oxidation of AA and subsequent production of DHA in neurons are associated with a decrease in GSH concentrations, alterations in glucose metabolism and neuronal death. To date, the endogenous molecules that act as intrinsic regulators of neuronal necroptosis under conditions of oxidative stress are unknown. Here, we show that treatment with AA regulates the expression of pro- and antiapoptotic genes. Vitamin C also regulates the expression of RIPK1/MLKL, whereas the oxidation of AA in neurons induces morphological alterations consistent with necroptosis and MLKL activation. The activation of necroptosis by AA oxidation in neurons results in bubble formation, loss of membrane integrity, and ultimately, cellular explosion. These data suggest that necroptosis is a target for cell death induced by vitamin C.

Inhibition of Hypothalamic MCT4 and MCT1-MCT4 Expressions Affects Food Intake and Alters Orexigenic and Anorexigenic Neuropeptide Expressions.

Feeding behavior regulation is a complex process, which depends on the central integration of different signals, such as glucose, leptin, and ghrelin. Recent studies have shown that glial cells known as tanycytes that border the basal third ventricle (3V) detect glucose and then use glucose-derived signaling to inform energy status to arcuate nucleus (ARC) neurons to regulate feeding behavior. Monocarboxylate transporters (MCT) 1 and MCT4 are localized in the cellular processes of tanycytes, which could facilitate monocarboxylate release to orexigenic and anorexigenic neurons. We hypothesize that MCT1 and MCT4 inhibitions could alter the metabolic communication between tanycytes and ARC neurons, affecting feeding behavior. We have previously shown that MCT1 knockdown rats eat more and exhibit altered satiety parameters. Here, we generate MCT4 knockdown rats and MCT1-MCT4 double knockdown rats using adenovirus-mediated transduction of a shRNA into the 3V. Feeding behavior was evaluated in MCT4 and double knockdown animals, and neuropeptide expression in response to intracerebroventricular glucose administration was measured. MCT4 inhibition produced a decrease in food intake, contrary to double knockdown. MCT4 inhibition was accompanied by a decrease in eating rate and mean meal size and an increase in mean meal duration, parameters that are not changed in the double knockdown animals with exception of eating rate. Finally, we observed a loss in glucose regulation of orexigenic neuropeptides and abnormal expression of anorexigenic neuropeptides in response to fasting when these transporters are inhibited. Taken together, these results indicate that MCT1 and MCT4 expressions in tanycytes play a role in feeding behavior regulation.

Time to Diagnosis in Cushing's Syndrome: A Meta-Analysis Based on 5367 Patients.

CONTEXT: Signs and symptoms of Cushing's syndrome (CS) overlap with common diseases, such as the metabolic syndrome, obesity, osteoporosis, and depression. Therefore, it can take years to finally diagnose CS, although early diagnosis is important for prevention of complications. OBJECTIVE: The aim of this study was to assess the time span between first symptoms and diagnosis of CS in different populations to identify factors associated with an early diagnosis. DATA SOURCES: A systematic literature search via PubMed was performed to identify studies reporting on time to diagnosis in CS. In addition, unpublished data from patients of our tertiary care center and 4 other centers were included. STUDY SELECTION: Clinical studies reporting on the time to diagnosis of CS were eligible. Corresponding authors were contacted to obtain additional information relevant to the research question. DATA EXTRACTION: Data were extracted from the text of the retrieved articles and from additional information provided by authors contacted successfully. From initially 3326 screened studies 44 were included. DATA SYNTHESIS: Mean time to diagnosis for patients with CS was 34 months (ectopic CS: 14 months; adrenal CS: 30 months; and pituitary CS: 38 months; P < .001). No difference was found for gender, age (<18 and ≥18 years), and year of diagnosis (before and after 2000). Patients with pituitary CS had a longer time to diagnosis in Germany than elsewhere. CONCLUSIONS: Time to diagnosis differs for subtypes of CS but not for gender and age. Time to diagnosis remains to be long and requires to be improved.

Author Correction: Adenovirus-mediated suppression of hypothalamic glucokinase affects feeding behavior.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Factors influencing cardiometabolic risk profile in patients with psoriasis.

BACKGROUND: Psoriasis has been associated with metabolic syndrome and with an increased cardiovascular risk especially in patients with severe disease. The goal of this study was to estimate the prevalence of metabolic syndrome and other cardiovascular risk factors and its association with the psoriasis severity, sex and age. METHODS: Consecutive patients with psoriasis were enrolled in a prospective study over a 1-year period. Blood samples were collected. Psoriasis area and severity index (PASI) and body surface area scores and two dermatology quality of life (DQOL) questionnaires were used to evaluate psoriasis severity and the impact of the disease. RESULTS: Altogether 178 patients were included, of whom 44% had moderate-severe psoriasis. The overall prevalence of metabolic syndrome was 30% (men 34%, women 26%) without significant differences between patients with severe and mild disease. Age and menopause appeared to increase the risk for metabolic syndrome. Patients with severe psoriasis smoked more heavily, were more likely to have diabetes or insulin resistance and had higher homocysteine and lower high density lipoprotein cholesterol (HDL-C) levels than patients with mild psoriasis (P < 0.05). In women, a higher waist circumference was observed. Women had higher HDL-C levels and lower smoking and alcohol consumption rates. In accordance with the systematic coronary risk evaluation system, 18% of the patients had a high 10-year risk of fatal cardiovascular disease. CONCLUSIONS: Psoriasis severity was associated with diabetes, insulin-resistance, smoking habit and higher cardiovascular risk. Metabolic syndrome was related to age and menopause but not to psoriasis severity.