Effects of Type 2 Diabetes on the Neuropsychological Profile in Mild Cognitive Impairment.

Background: Diabetes is one of the main risk factors for developing mild cognitive impairment (MCI) and Alzheimer's disease. Most studies have demonstrated a worse performance in executive function, verbal fluency, and information processing speed in patients with diabetes. Objective: To assess the cognitive functioning of persons with type 2 diabetes and amnesic mild cognitive impairment (aMCI-T2DM) compared to persons with aMCI without diabetes and persons without diabetes or aMCI as controls, to understand the role of diabetes in the neuropsychological profile. Methods: Cross-sectional study involving a sample of 83 patients, ranging in age from 61 to 85 years and divided into three groups: aMCI-T2DM (27 patients), aMCI (29 patients), Controls (27 individuals). All the participants undertook an exhaustive neuropsychological assessment (auditory-verbal and visual memory, attention, information processing speed, language, executive function, and depression). Results: Both groups of aMCI patients performed significantly worse than the controls in all the neuropsychological tests. A significant linear tendency (p trend < 0.05) was found between groups, with the aMCI-T2DM group presenting worse results in global cognition assessed by the Mini-Mental State Examination and Montreal Cognitive Assessment; Rey-Osterrieth Complex Figure Test; Auditory Verbal Learning Test; Trail Making Test A and B, Verbal Fluency Test, and Hamilton Depression Rating Scale. Conclusions: aMCI patients with or without diabetes showed worse cognitive function compared to persons without diabetes or aMCI. Additionally, aMCI patients without T2DM presented a different cognitive profile than aMCI patients with T2DM, which tended towards presenting worse cognitive functions such as global cognition, memory, attention, executive function, and language.

Effects of GLP-1 receptor agonists on neurological complications of diabetes.

Emerging evidence suggests that treatment with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) could be an interesting treatment strategy to reduce neurological complications such as stroke, cognitive impairment, and peripheral neuropathy. We performed a systematic review to examine the evidence concerning the effects of GLP-1 RAs on neurological complications of diabetes. The databases used were Pubmed, Scopus and Cochrane. We selected clinical trials which analysed the effect of GLP-1 RAs on stroke, cognitive impairment, and peripheral neuropathy. We found a total of 19 studies: 8 studies include stroke or major cardiovascular events, 7 involve cognitive impairment and 4 include peripheral neuropathy. Semaglutide subcutaneous and dulaglutide reduced stroke cases. Liraglutide, albiglutide, oral semaglutide and efpeglenatide, were not shown to reduce the number of strokes but did reduce major cardiovascular events. Exenatide, dulaglutide and liraglutide improved general cognition but no significant effect on diabetic peripheral neuropathy has been reported with GLP-1 RAs. GLP-1 RAs are promising drugs that seem to be useful in the reduction of some neurological complications of diabetes. However, more studies are needed.

Insulin-Related Biomarkers in Cerebrospinal Fluid in Mild Cognitive Impairment and Alzheimer's Disease: A Systematic Review.

BACKGROUND: Glucose metabolism and insulin signaling alterations play an important role in Alzheimer's disease (AD) pathogenesis. Researchers have extensively attempted to characterize the exact pathophysiological mechanisms in the cerebrospinal fluid (CSF), as evidence concerning this fluid biomarkers is expected to enhance AD diagnosis' specificity and accuracy and serve as an early disease detection tool. There is controversy about insulin levels in the CSF relationship with mild cognitive impairment (MCI) and AD. OBJECTIVE: This systematic review provides an overview of the state-of-the-art knowledge about insulin-related CSF biomarkers in AD and MCI. METHODS: We performed a qualitative systematic literature review of reported data of CSF glucose, insulin, or insulin-related molecules in humans with AD or MCI, consulting the electronic databases Medline, Scopus, Web of Science, Cochrane, and BASE until May 2022. RESULTS: We selected 19 studies, 10 of them reporting data on CSF insulin and 8 on insulin-related molecules like growth factors or their binding proteins. They predominantly found decreased levels of CSF insulin and increased levels of CSF insulin-related growth factors and their binding proteins. CONCLUSION: Due to the studies' protocols and results heterogeneity, we recommend a larger database of clinical trials with similar characteristics for a better understanding of this relationship.

Melodic Intonation Therapy in Post-Stroke Non-Fluent Aphasia and Its Effects on Brain Plasticity.

Melodic Intonation Therapy (MIT) is one of the most well-known therapies for the rehabilitation of speech in patients with non-fluent aphasia and which is thought to promote right-hemisphere involvement in language processing. This review focuses on the study of language lateralization and/or neuroplastic reorganization with neuroimaging and/or neurophysiological techniques in non-fluent aphasic patients post-stroke during or after MIT. A systematic search was carried out according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) in databases (PubMed, Scopus, EMBASE, Dialnet, Web of Science, Cochrane) with the keywords melodic intonation therapy, neuroimaging, functional magnetic resonance, and positron emission tomography and the boolean operators AND and OR. Articles including patients of all ages and either sex with any type of aphasia post-stroke and in any language, which studied language lateralization and/or neuroplastic reorganization after or during MIT were included. Articles which did not achieve the objectives, revisions and conferences were excluded. Different results were obtained from the 16 studies included in the review: predominantly greater activation of the right hemisphere but also of the left hemisphere or both. MIT is an effective therapy to rehabilitate non-fluent aphasic patients post-stroke. It involves different neurobiological mechanisms and depends on multiple individual factors. Studies with larger samples are necessary.

Cognitive Functioning and Cortical Brain Thickness in Acromegaly Patients: A Pilot study.

OBJECTIVE: Cognitive effects in acromegaly patients are poorly understood and the mechanisms involved are still unclear. The aim of this study was to evaluate the cognitive function, depression, and quality of life of acromegaly patients treated with pegvisomant versus somatostatin analogues (SRLs) and to analyze the effect of the different treatments on cognition and possible structural brain changes. METHODS: This cross-sectional study involved 23 acromegaly patients divided into two groups according to treatment modality: One group of 9 patients treated with pegvisomant and another group of 14 patients treated with SRLs. All participants underwent blood analysis, neuropsychological tests, depression tests, quality of life assessment, and 3-Tesla magnetic resonance imaging. RESULTS: We found no significant differences between groups in the neuropsychological tests, depression or quality of life; nor in the whole-brain cortical thickness. In the SRL group, the volume of the thalamus correlated positively with executive function, a correlation not found in the pegvisomant group. In addition, the pegvisomant group had significantly higher levels of insulin than the SRL group. CONCLUSIONS: In conclusion, in this pilot study, the type of pharmacological treatment in patients with acromegaly and good glycemic control did not influence the cognitive function and cortical brain thickness. However, pegvisomant could play a neuroprotective role on the thalamus that will have to be demonstrated with larger samples in future studies.

Antidiabetic Drugs in Alzheimer's Disease and Mild Cognitive Impairment: A Systematic Review.

INTRODUCTION: Considering that Alzheimer's disease (AD) and diabetes mellitus share pathophysiological features and AD remains with no cure, antidiabetic drugs like intranasal insulin, glitazones, metformin, and liraglutide are being tested as a potential treatment. OBJECTIVE: The aim of this systematic review was to assess the efficacy of antidiabetic drugs in patients with AD, mild cognitive impairment (MCI), or subjective cognitive complaints (SCCs). Cognition was studied as the primary outcome and modulation of AD biomarkers, and imaging was also assessed as a secondary outcome. METHODS: We conducted a search in the electronic databases PubMed/MEDLINE, EMBASE, and Scopus seeking clinical trials evaluating the effect on cognition of antidiabetic drugs in patients with AD, MCI, or SCCs. RESULTS: A total of 23 articles were found eligible. Intranasal regular insulin improved verbal memory in most studies, especially in apoE4- patients, but results in other cognitive domains were unclear. Detemir improved cognition after 2 months of treatment, but it did not after 4 months. Pioglitazone improved cognition in diabetic patients with AD or MCI in 3 clinical trials, but it is controversial as 2 other studies did not show effect. Metformin and liraglutide showed promising results, but further research is needed as just 2 clinical trials involved each of these drugs. Almost all drugs tested were shown to modulate AD biomarkers and imaging. CONCLUSIONS: Intranasal insulin, pioglitazone, metformin, and liraglutide are promising drugs that could be useful in the treatment of AD. However, many questions remain to be answered in future studies, so no particular antidiabetic drug can currently be recommended to treat AD.

ACROSTART: A retrospective study of the time to achieve hormonal control with lanreotide Autogel treatment in Spanish patients with acromegaly.

OBJECTIVES: The ACROSTART study was intended to determine the time to achieve normalization of GH and IGF-I levels in responding patients with acromegaly administered different dosage regimens of lanreotide Autogel (Somatuline® Autogel®). METHODS: From March 2013 to October 2013, clinical data from 57 patients from 17 Spanish hospitals with active acromegaly treated with lanreotide for ≥4 months who achieved hormonal control (GH levels <2.5ng/ml and/or normalized IGF-I levels in ≥2 measurements) were analyzed. The primary objective was to determine the time from start of lanreotide treatment to hormonal normalization. RESULTS: Median patient age was 64 years, 21 patients were male, 39 patients had undergone surgery, and 14 patients had received radiotherapy. Median hormonal values at start of lanreotide treatment were: GH, 2.6ng/ml; IGF-I, 1.6×ULN. The most common starting dose of lanreotide was 120mg (29 patients). The main initial regimens were 60mg/4 weeks (n=13), 90mg/4 weeks (n=6), 120mg/4 weeks (n=13), 120mg/6 weeks (n=6), and 120mg/8 weeks (n=9). An initial treatment regimen with a long interval (≥6 weeks) was administered in 25 patients. Mean duration of lanreotide treatment was 68 months (7-205). Median time to achieve hormonal control was 4.9 months. Injections were managed without healthcare assistance in 13 patients. Median number of visits to endocrinologists until hormonal control was achieved was 3. Fifty-one patients were "satisfied"/"very satisfied" with treatment and 49 patients did not miss any dose. CONCLUSIONS: Real-life treatment with lanreotide Autogel resulted in early hormonal control in responding patients, with high treatment adherence and satisfaction despite disparity in starting doses and dosing intervals.

Treatment adherence to pegvisomant in patients with acromegaly in Spain: PEGASO study.

PURPOSE: The burden of chronic daily subcutaneous administration of pegvisomant on adherence has not been previously studied. This study was aimed to determine the adherence to pegvisomant treatment in acromegaly patients in the real-world clinical practice setting in Spain. METHODS: Multicenter, observational, descriptive, cross-sectional study in patients with acromegaly treated with pegvisomant for at least 12 months. Patient adherence was indirectly determined by Batalla and Haynes-Sackett questionnaires and directly by prescription record review. Additionally, treatment satisfaction was assessed by the Treatment Satisfaction with Medicines Questionnaire (SATMED-Q) and treatment convenience by an ad-hoc Pegvisomant questionnaire. Errors in reconstitution and administration process were determined by direct observation. RESULTS: 108 patients were included in the analysis. Rates of adherence varied from 60.7 to 92.1% and did not correlate with disease control. Older patient age and alternative schedules other than daily pegvisomant dosing were associated with lower adherence. Treatment satisfaction and convenience was high, with a mean (SD) total SATMED-Q score of 74.6 ± 15.4 over 100 and a total ad-hoc Pegvisomant questionnaire score of 71.2 ± 15.2 over 100. 34.3% of patients made mistakes during the reconstitution /administration process. CONCLUSIONS: Patient adherence to pegvisomant was high (60.7-92.1%), but more than a third of the patients in the study made mistakes during the administration process, with a potential impact on disease control. Besides dosing compliance, correct administration of medication should be carefully assessed in these patients.

Music Therapy in Parkinson's Disease.

OBJECTIVES: Parkinson's disease (PD) is a chronic progressive neurologic disorder involving degeneration of the dopaminergic system. Its clinical manifestations include motor and nonmotor symptoms. Several nonpharmacologic therapies, such as music therapy (MT), have recently been developed in order to improve the clinical manifestations of this disease. The aim of this narrative literature review is to analyze the scientific evidence for the therapeutic effects of music in PD. DESIGN: We undertook a search in the databases of PubMed, PsycINFO, Scopus, MEDLINE, and Science Direct. SETTINGAND PARTICIPANTS: Inclusion criteria were articles including persons with PD rehabilitated with an MT intervention. MEASURES: Keywords used were music therapy, Parkinson's disease, auditory cueing, non-motor symptoms, motor symptoms, and quality of life. RESULTS: We detected a total of 27 articles, all of which analyzed the therapeutic effects of MT in PD. Of these, 20 studies analyzed the effects in motor symptoms (16 showed beneficial effects and 4, nonbeneficial effects); 9 studies analyzed the effects in nonmotor symptoms, 7 of which demonstrated beneficial effects; and 8 studies analyzed the effects on quality of life, with 6 reporting benefits. None of the articles analyzing nonmotor symptoms and quality of life showed negative effects. CONCLUSIONS/IMPLICATIONS: Most of the studies analyzed demonstrated that MT has beneficial effects for the nonpharmacologic treatment of motor and nonmotor symptoms and quality of life of persons with PD. The use of music as a therapeutic tool combined with conventional therapies should be taken into account.

Brain Functional Connectivity Is Modified by a Hypocaloric Mediterranean Diet and Physical Activity in Obese Women.

Functional magnetic resonance imaging (fMRI) in the resting state has shown altered brain connectivity networks in obese individuals. However, the impact of a Mediterranean diet on cerebral connectivity in obese patients when losing weight has not been previously explored. The aim of this study was to examine the connectivity between brain structures before and six months after following a hypocaloric Mediterranean diet and physical activity program in a group of sixteen obese women aged 46.31 ± 4.07 years. Before and after the intervention program, the body mass index (BMI) (kg/m²) was 38.15 ± 4.7 vs. 34.18 ± 4.5 (p < 0.02), and body weight (kg) was 98.5 ± 13.1 vs. 88.28 ± 12.2 (p < 0.03). All subjects underwent a pre- and post-intervention fMRI under fasting conditions. Functional connectivity was assessed using seed-based correlations. After the intervention, we found decreased connectivity between the left inferior parietal cortex and the right temporal cortex (p < 0.001), left posterior cingulate (p < 0.001), and right posterior cingulate (p < 0.03); decreased connectivity between the left superior frontal gyrus and the right temporal cortex (p < 0.01); decreased connectivity between the prefrontal cortex and the somatosensory cortex (p < 0.025); and decreased connectivity between the left and right posterior cingulate (p < 0.04). Results were considered significant at a voxel-wise threshold of p ≤ 0.05, and a cluster-level family-wise error correction for multiple comparisons of p ≤ 0.05. In conclusion, functional connectivity between brain structures involved in the pathophysiology of obesity (the inferior parietal lobe, posterior cingulate, temporo-insular cortex, prefrontal cortex) may be modified by a weight loss program including a Mediterranean diet and physical exercise.

BIM-23A760 influences key functional endpoints in pituitary adenomas and normal pituitaries: molecular mechanisms underlying the differential response in adenomas.

Chimeric somatostatin/dopamine compounds such as BIM-23A760, an sst2/sst5/D2 receptors-agonist, have emerged as promising new approaches to treat pituitary adenomas. However, information on direct in vitro effects of BIM-23A760 in normal and tumoral pituitaries remains incomplete. The objective of this study was to analyze BIM-23A760 effects on functional parameters (Ca2+ signaling, hormone expression/secretion, cell viability and apoptosis) in pituitary adenomas (n = 74), and to compare with the responses of normal primate and human pituitaries (n = 3-5). Primate and human normal pituitaries exhibited similar sst2/sst5/D2 expression patterns, wherein BIM-23A760 inhibited the expression/secretion of several pituitary hormones (specially GH/PRL), which was accompanied by increased sst2/sst5/D2 expression in primates and decreased Ca2+ concentration in human cells. In tumoral pituitaries, BIM-23A760 also inhibited Ca2+ concentration, hormone secretion/expression and proliferation. However, BIM-23A760 elicited stimulatory effects in a subset of GHomas, ACTHomas and NFPAs in terms of Ca2+ signaling and/or hormone secretion, which was associated with the relative somatostatin/dopamine-receptors levels, especially sst5 and sst5TMD4. The chimeric sst2/sst5/D2 compound BIM-23A760 affects multiple, clinically relevant parameters on pituitary adenomas and may represent a valuable therapeutic tool. The relative ssts/D2 expression profile, particularly sst5 and/or sst5TMD4 levels, might represent useful molecular markers to predict the ultimate response of pituitary adenomas to BIM-23A760.

The pro-/anti-inflammatory effects of different fatty acids on visceral adipocytes are partially mediated by GPR120.

PURPOSE: This study examines whether G-protein coupled receptor 120 (GPR120) is involved in the pro-/anti-inflammatory effects of different types of fatty acids (FAs) in human visceral adipocytes, and whether these effects may be altered in obesity, a state with a chronic inflammation. METHODS: Pro-/anti-inflammatory effects of palmitic, oleic, linoleic and docosahexaenoic acids on human visceral adipocytes were tested in mature adipocytes from non-obese and morbidly obese (MO) subjects. Also, the effects of these FAs were tested when the GPR120 gene was silenced. RESULTS: In adipocytes from non-obese subjects, palmitic and linoleic acids increased TNF-α and IL-6 mRNA expression (p < 0.05), and decreased IL-10 and adiponectin expression (p < 0.05). However, oleic and docosahexaenoic acids (DHA) produced the opposite effect (p < 0.05). In adipocytes from MO subjects, all FAs used increased TNF-α and IL-6 expression (p < 0.05). Palmitic and linoleic acids decreased IL-10 and adiponectin expression (p < 0.05), but oleic acid and DHA did not have significant effects. Only oleic acid increased adiponectin expression (p < 0.05). The effects of FAs on TNF-α, IL-6, IL-10 and adiponectin expression in non-obese and MO subjects were significantly annulled when the GPR120 gene was silenced in visceral adipocytes differentiated from human mesenchymal stem cells. CONCLUSIONS: FAs are capable of directly acting on visceral adipocytes to modulate differently TNF-α, IL-6, IL-10 and adiponectin expression, with a different and greater effect in MO subjects. These effects are largely annulled when GPR120 expression was silenced, which suggests that they could be mediated by GPR120.

Octreotide and pasireotide (dis)similarly inhibit pituitary tumor cells in vitro.

Somatostatin analogs (SSA) are the mainstay of pharmacological treatment for pituitary adenomas. However, some patients escape from therapy with octreotide, a somatostatin receptor 2 (sst2)-preferring SSA, and pasireotide, a novel multi-sst-preferring SSA, may help to overcome this problem. It has been proposed that correspondence between sst1-sst5 expression pattern and SSA-binding profile could predict patient's response. To explore the cellular/molecular features associated with octreotide/pasireotide response, we performed a parallel comparison of their in vitro effects, evaluating sst1-sst5 expression, intracellular Ca2+ signaling ([Ca2+]i), hormone secretion and cell viability, in a series of 85 pituitary samples. Somatotropinomas expressed sst5>sst2, yet octreotide reduced [Ca2+]i more efficiently than pasireotide, while both SSA similarly decreased growth hormone release/expression and viability. Corticotropinomas predominantly expressed sst5, but displayed limited response to pasireotide, while octreotide reduced functional endpoints. Non-functioning adenomas preferentially expressed sst3 but, surprisingly, both SSA increased cell viability. Prolactinomas mainly expressed sst1 but were virtually unresponsive to SSA. Finally, both SSA decreased [Ca2+]i in normal pituitaries. In conclusion, both SSA act in vitro on pituitary adenomas exerting both similar and distinct effects; however, no evident correspondence was found with the sst1-sst5 profile. Thus, it seems plausible that additional factors, besides the simple abundance of a given sst, critically influence the SSA response.

A Probabilistic Model for Cushing's Syndrome Screening in At-Risk Populations: A Prospective Multicenter Study.

CONTEXT: Cushing's syndrome (CS) is challenging to diagnose. Increased prevalence of CS in specific patient populations has been reported, but routine screening for CS remains questionable. To decrease the diagnostic delay and improve disease outcomes, simple new screening methods for CS in at-risk populations are needed. OBJECTIVE: To develop and validate a simple scoring system to predict CS based on clinical signs and an easy-to-use biochemical test. DESIGN: Observational, prospective, multicenter. SETTING: Referral hospital. PATIENTS: A cohort of 353 patients attending endocrinology units for outpatient visits. INTERVENTIONS: All patients were evaluated with late-night salivary cortisol (LNSC) and a low-dose dexamethasone suppression test for CS. MAIN OUTCOME MEASURES: Diagnosis or exclusion of CS. RESULTS: Twenty-six cases of CS were diagnosed in the cohort. A risk scoring system was developed by logistic regression analysis, and cutoff values were derived from a receiver operating characteristic curve. This risk score included clinical signs and symptoms (muscular atrophy, osteoporosis, and dorsocervical fat pad) and LNSC levels. The estimated area under the receiver operating characteristic curve was 0.93, with a sensitivity of 96.2% and specificity of 82.9%. CONCLUSIONS: We developed a risk score to predict CS in an at-risk population. This score may help to identify at-risk patients in non-endocrinological settings such as primary care, but external validation is warranted.

Alzheimer's like brain changes correlate with low adiponectin plasma levels in type 2 diabetic patients.

AIM: To study the association between adiponectin plasma levels, and gray matter brain volume and cerebral glucose metabolism in a group of type 2 diabetes patients. METHODS: We studied 25 type 2 diabetes patients and 25 age- and gender-matched healthy control participants. Biochemical analysis and structural cerebral magnetic resonance imaging, including voxel-based morphometry and (18)-fluorodeoxyglucose positron emission tomography, were performed. The gray matter volumes and metabolism changes were analyzed using statistical parametric mapping (SPM8). RESULTS: Lower levels of adiponectin correlated with a lower gray matter volume in temporal regions and with reduced cerebral glucose metabolism in temporal regions (p<0.001), adjusted for age, gender, education, and the presence of at least one epsilon 4 allele for the apolipoprotein E (APOEε4 genotype). CONCLUSIONS: Positive correlations between adiponectin plasma levels and both gray matter volume and cerebral glucose metabolism were found, predominantly in temporal regions, as in Alzheimer's disease. Adiponectin might be a biomarker for the cognitive decline associated with type 2 diabetic patients.

Effect of Roux-en-Y gastric bypass-induced weight loss on the transcriptomic profiling of subcutaneous adipose tissue.

BACKGROUND: The changes in the transcriptomic profiling of subcutaneous adipose tissue (SAT) when weight loss stabilizes after a Roux-en-Y gastric bypass (RYGB) are still largely unknown. OBJECTIVES: To investigate the changes produced in SAT gene expression of morbidly obese women when their weight loss stabilizes 2 years after RYGB. SETTING: University hospital. METHODS: SAT biopsies of the periumbilical area were taken before and 2 years after RYGB. Gene expression levels were assessed by microarray analysis and significant differences in gene expression were validated by real-time quantitative polymerase chain reaction. The findings were also confirmed in an independent population of morbidly obese women. RESULTS: Microarray analysis revealed that the overexpressed differentially expressed genes have a prominent role in the pathways involved in biosynthetic processes, especially lipid or carboxylic ones (stearoyl-Coenzyme A desaturase-1, fatty acid desaturase-1, fatty acid elongase-6, ATP citrate lyase, fatty acid synthase, lipin-1, monoacylglycerol O-acyltransferase, patatin-like phospholipase domain containing-3, phosphate cytidylyltransferase-2, cholesteryl ester transfer protein, transmembrane 7 superfamily member 2, pyruvate carboxylase, and glycogen synthase 2). Most of the underexpressed differentially expressed genes are related with immune system and inflammation processes (immune responses, response to stress, cell death, regulation of biological quality, immune effector process, the response to endogenous stimulus, and the response to other types of stimulus). CONCLUSION: An improvement of the SAT inflammatory and immune profile and an induction of genes involved in the regulation of lipid metabolism are shown when weight loss stabilizes 2 years after RYGB. Most of the genes shown are clearly linked to obesity and other metabolic disorders.

The expression of genes involved in jejunal lipogenesis and lipoprotein synthesis is altered in morbidly obese subjects with insulin resistance.

The dyslipidemia associated with type 2 diabetes mellitus (T2DM) is an important risk factor for atherosclerotic cardiovascular disease. However, until now little attention has been paid to the role that the intestine might have. The aim of this research was to determine the relation between insulin resistance and intestinal de novo lipogenesis/lipoprotein synthesis in morbidly obese subjects and to study the effect of insulin on these processes. Jejunal mRNA expression of the different genes involved in the intestinal de novo lipogenesis/lipoprotein synthesis was analyzed in three groups of morbidly obese subjects: Group 1 with low insulin resistance (MO-low-IR), group 2 with high insulin resistance (MO-high-IR), and group 3 with T2DM and treatment with metformin (MO-metf-T2DM). In addition, intestinal epithelial cells (IECs) from MO-low-IR were incubated with different doses of insulin/glucose. In Group 2 (MO-high-IR), the jejunal mRNA expression levels of apo A-IV, ATP-citrate lyase (ACLY), pyruvate dehydrogenase (lipoamide) beta (PDHB), and sterol regulatory element-binding protein-1c (SREBP-1c) were significantly higher and acetyl-CoA carboxylase alpha (ACC1) and fatty-acid synthase lower than in Group 1 (MO-low-IR). In Group 3 (MO-metf-T2DM), only the ACLY and PDHB mRNA expressions were significantly higher than in Group 1 (MO-low-IR). The mRNA expression of most of the genes studied was significantly linked to insulin and glucose levels. The incubation of IEC with different doses of insulin and glucose produced a higher expression of diacylglycerol acyltransferase 2, microsomal triglyceride transfer protein, apo A-IV, SREBP-1c, and ACC1 when both, glucose and insulin, were at a high concentration. However, with only high insulin levels, there were higher apo A-IV, PDHB and SREBP-1c expressions, and a lower ACLY expression. In conclusion, the jejunum of MO-high-IR has a decreased mRNA expression of genes involved in de novo fatty-acid synthesis and an increase of genes involved in acetyl-CoA and lipoprotein synthesis. This effect is attenuated by metformin. In addition, the expression of most of the genes studied was found to be regulated by insulin.

C-peptide modifies leptin and visfatin secretion in human adipose tissue.

OBJECTIVE: The effects of C-peptide on adipose tissue, an organ involved in the development of obesity and insulin resistance, are not yet well known. The aim of this study was to determine whether C-peptide could be involved in the regulation of the adipocytokine synthesis in human visceral adipose tissue. METHODS: The association between C-peptide and different serum adipocytokines, with an intravenous glucose tolerance test (IVGTT), and in an in vitro study in subjects without obesity and in subjects with morbid obesity were analyzed. RESULTS: In different multiple regression analysis models, C-peptide and C-peptide increase above basal levels during total IVGTT and between 0 and 10 min were associated positively with leptin and negatively with visfatin. Rhodamine-labeled C-peptide binds to human adipocytes, and this binding was blocked with excess of unlabeled C-peptide. Exposure of human visceral explants and adipocytes from subjects with morbid obesity to C-peptide at 1 and 10 nM induced a significant increase in leptin and a decrease in visfatin secretion. In subjects without obesity, these C-peptide effects were found mainly at 10 nM. These effects can be inhibited by phosphatidylinositol 3-kinase (PI3K) or protein kinase B (PKB) inhibitors. CONCLUSIONS: C-peptide may be involved in the regulation of leptin and visfatin secretion, molecules intimately involved in energy homeostasis processes, through PI3K or PKB pathways.

In1-ghrelin splicing variant is overexpressed in pituitary adenomas and increases their aggressive features.

Pituitary adenomas comprise a heterogeneous subset of pathologies causing serious comorbidities, which would benefit from identification of novel, common molecular/cellular biomarkers and therapeutic targets. The ghrelin system has been linked to development of certain endocrine-related cancers. Systematic analysis of the presence and functional implications of some components of the ghrelin system, including native ghrelin, receptors and the recently discovered splicing variant In1-ghrelin, in human normal pituitaries (n = 11) and pituitary adenomas (n = 169) revealed that expression pattern of ghrelin system suffers a clear alteration in pituitary adenomasas compared with normal pituitary, where In1-ghrelin is markedly overexpressed. Interestingly, in cultured pituitary adenoma cells In1-ghrelin treatment (acylated peptides at 100 nM; 24-72 h) increased GH and ACTH secretion, Ca(2+) and ERK1/2 signaling and cell viability, whereas In1-ghrelin silencing (using a specific siRNA; 100 nM) reduced cell viability. These results indicate that an alteration of the ghrelin system, specially its In1-ghrelin variant, could contribute to pathogenesis of different pituitary adenomas types, and suggest that this variant and its related ghrelin system could provide new tools to identify novel, more general diagnostic, prognostic and potential therapeutic targets in pituitary tumors.

[Glucagon-like peptide-1 (GLP-1) mimetics: a new treatment for Alzheimer's disease?]. / Análogos del glucagon-like peptide-1 (GLP-1): ¿una nueva estrategia de tratamiento para la enfermedad de Alzheimer?

INTRODUCTION: The glucagon-like peptide-1 (GLP-1) mimetics are an established therapeutic option for patients with type 2 diabetes. However, the properties of the GLP-1 mimetics go beyond the strict metabolic control of the patients with diabetes. The neuroprotective effects of GLP-1 have been shown in recent studies opening new areas of research in neurodegenerative diseases such as Alzheimer's disease (AD), among others. AIM. Systematic review including experimental studies and human clinical trials demonstrating the neuroprotective properties of GLP-1 mimetics in AD. DEVELOPMENT: The experimental studies that have been conducted in rodent models of AD have demonstrated the neuroprotective properties of GLP-1 in the central nervous system reducing beta-amyloid plaques, the oxidative stress and the inflammatory brain response. Clinical trials in patients with cognitive impairment and AD testing the effects of GLP-1 analogs have recently started. CONCLUSION: The GLP-1 analogs have neuroprotective properties. Considering that type 2 diabetes is a risk factor for cognitive impairment and dementia, the benefits of GLP-1 mimetics on cognition must be considered. Likewise, the GLP-1 mimetics represent a promising treatment for neurodegenerative diseases such as AD.

TITLE: Analogos del glucagon-like peptide-1 (GLP-1): una nueva estrategia de tratamiento para la enfermedad de Alzheimer?Introduccion. Los analogos del glucagon-like peptide-1 (GLP-1) son una opcion terapeutica establecida en los pacientes con diabetes tipo 2. Sin embargo, las propiedades de los analogos del GLP-1 van mas alla del control estrictamente metabolico del paciente diabetico. Los efectos neuroprotectores de los analogos del GLP-1 se han puesto de manifiesto en estudios recientes y han abierto nuevos campos de investigacion en trastornos neurodegenerativos como la enfermedad de Alzheimer (EA), entre otros. Objetivo. Revision sistematica de los estudios experimentales y ensayos clinicos en humanos que demuestran las propiedades neuroprotectoras de los analogos del GLP-1 en la EA. Desarrollo. Los estudios experimentales que se han llevado a cabo en modelos de roedores con EA demuestran las propiedades neuroprotectoras de los analogos del GLP-1 sobre el sistema nervioso central que reducen las placas de beta-amiloide, el estres oxidativo y la respuesta inflamatoria cerebral. Recientemente se han puesto en marcha estudios con analogos del GLP-1 en humanos con deterioro cognitivo y EA. Conclusiones. Los analogos del GLP-1 presentan propiedades neuroprotectoras. Al considerarse la diabetes tipo 2 un factor de riesgo para el deterioro cognitivo y la demencia, deben considerarse los beneficios de los analogos del GLP-1 sobre la cognicion. Del mismo modo, los analogos del GLP-1 suponen un tratamiento prometedor en la EA.