Hypothesis of the neuroendocrine cortisol pathway gene role in the comorbidity of depression, type 2 diabetes, and metabolic syndrome

Causal relationship between diabetes and depression: A bidirectional Mendelian randomization study

OBJECTIVE

This study explores the causal relationship between diabetes and depression using a two-sample Mendelian Randomization (TSMR) method.

METHODS

The study selected single nucleotide polymorphisms (SNPs) closely associated with diabetes and depression in European populations from the Genome-Wide Association Study (GWAS) database, to serve as instrumental variables (IVs). The main evaluation method was inverse variance weighted analysis (IVW), supplemented by verification using Weighted median, Weighted mode, and MR Egger methods. The Odds Ratio (OR) and 95 % Confidence Interval (CI) were used as the main evaluation indicators, along with sensitivity analysis.

RESULTS

This study found a negative correlation between diabetes and depression, suggesting that diabetes may reduce the risk of depression [IVW(FE): OR: 0.901, 95 % CI: 0.823 to 0.987; P = 0.025 < 0.05]. This finding was further confirmed by the Weighted median [OR: 0.844, 95 % CI: 0.730 to 0.974; P = 0.021 < 0.05] and Weighted mode method [OR: 0.766, 95 % CI: 0.637 to 0.921; P = 0.006 < 0.05]. However, the reverse showed no causal relationship between depression and diabetes (P > 0.05). Sensitivity analysis found no pleiotropy, and there were no large influences from individual SNPs on the result's robustness; the results are stable and reliable.

CONCLUSION

For the first time, this study using TSMR analysis found a negative correlation between diabetes and the risk of depression onset in European populations, suggesting that diabetes might reduce the risk of depression. But as the mechanisms are still unclear, these findings warrant further study.

Interactome analysis implicates class II transactivator (CIITA) in depression and other neuroinflammatory disorders

PURPOSE

Inappropriate inflammatory responses within the nervous system (neuroinflammation) have been implicated in several neurological conditions. Class II transactivator (CIITA), a principal regulator of the major histocompatibility complex II (MHCII), is known to play essential roles in inflammation. Hence, CIITA and its interactors could be potentially involved in multiple neurological disorders. However, the molecular mechanisms underlying CIITA-mediated neuroinflammation (NI) are yet to be understood.

MATERIALS AND METHODS

In this regard, we analyzed the potential involvement of CIITA and its interactome in the regulation of neuroinflammation. In the present study, using various computational tools, we aimed (1) to identify NI-related proteins, (2) to filter the critical interactors in the CIITA-NI network, and (3) to analyze the protein-disease interactions and the associated molecular pathways through which CIITA could influence neuroinflammation.

RESULTS

CIITA was found to interact with P T GS2, GSK3B, and NR3C1 and may influence depressive disorders. Further, the IL4/IL13 pathway was found to be potentially underlying the CIITA-interactomemediated effects on neurological disorders. Moreover, CIITA was found to be connected to genes associated with depressive disorder through IL4, wherein CIITA was found to be potentially involved in depressive disorders through IL-4/IL-13 and hippo pathways. However, the present study is based on the existing data on protein interactomes and could be re-evaluated as newer interactions are discovered. Also, the functional mechanisms of CIITA's roles in neuroinflammation must be evaluated further.

CONCLUSION

Notwithstanding these limitations, the results presented here, could form a basis for further experimental studies to assess CIITA as a potential therapeutic target in managing depression and other neuroinflammatory disorders.

PI3K-AKT-mTOR signaling pathway regulates autophagy of hippocampal neurons in diabetic rats with chronic unpredictable mild stress

It is reported that the co-morbidities of diabetes and depression will be a new challenge for humanity. However, the underlying mechanism is not clear. The present study investigated the histopathology, autophagy of hippocampal neurons, and the PI3K-AKT- mTOR signaling pathway in type 2 diabetes with depression（T2DD） rats. The results showed that, the chronic unpredictable mild stress (CUMS), Type 2 diabetes mellitus (T2DM) and T2DD in rats were induced successfully. Compared with the CUMS and T2DM groups, the T2DD group performed significantly fewer autonomic activities in the open-field test, and longer immobile in the force swimming test, and increasing of Corticosterone (CORT) in blood. The number of pyknotic neurons at cornu ammonis 1 (CA1) and dentate gyrus (DG) of the hippocampus in T2DD was significantly increased compared with CUMS and T2DM groups. Moreover, compared with the CUMS and T2DM groups, the mitochondrial autophagosomes were most abundant in the T2DD group. As shown in western blot and immunofluorescence, compared with the control group, in the CUMS, T2DM and T2DD groups, significantly increased expression of Beclin-1 and LC3B and decreased P62 were detected. In the PC12 cells, the relative amount of parkin and LC3B in the CORT+HG group was significantly higher than that in the CORT and HG groups. Compared with the control group, p-AKT/AKT and p-mTOR/mTOR in CUMS, T2DM and T2DD groups were significantly decreased. Compared with the CUMS group, p-AKT/AKT, p-PI3K/PI3K and p-mTOR/mTOR in the T2DD group exhibited further decrease. Similar results were obtained in PC12 cells in vitro. It is suggests that memory and cognitive impairment in rats with co-morbidities of diabetes and depression might be related with hippocampal neuronal damage and autophagy increase, which was involved in the PI3K-AKT-mTOR signaling pathway.

Association of metabolic syndrome and its components with the risk of depressive symptoms: A systematic review and meta-analysis of cohort studies

BACKGROUND

The purpose of this meta-analysis was to quantitatively analyze the association between metabolic syndrome (MetS) and the risk of depressive symptoms.

METHODS

Three electronic databases (PubMed, Embase, and PsycINFO) were searched for articles published through February 15, 2022. Cohort studies evaluating the association between MetS and depressive symptoms were selected for inclusion in this study. A random-effects model was used to evaluate the pooled estimates of MetS, including each of its components, associated with depressive symptoms.

RESULTS

A total of 11 cohort studies were selected including >2.65 million participants. There was a significant association between MetS and depressive symptoms risk, albeit with a high degree of heterogeneity (relative risk = 1.29, 95 % confidence interval: 1.12-1.48; I2 = 79.3 %). This association was consistently significant in Western countries, but it was not significant in Asian countries. When stratified by sex, age, and geographical region, MetS and its components exhibited varying degrees of association with depressive symptoms.

CONCLUSIONS

MetS is a risk factor for depressive symptoms. Further large-scale prospective cohort studies are required to confirm our findings.

A new model for the treatment of type 2 diabetes mellitus based on rhythm regulations under the framework of psychosomatic medicine: a real-world study

We aimed to explore a new treatment model for type 2 diabetes mellitus (DM) based on rhythm regulation under the framework of psychosomatic medicine. Using psychotropics as rhythm regulators, 178 patients with DM were evaluated and divided into three groups: the antidiabetic treatment group (AT group), psychotropic treatment group (PT group), and combined antidiabetic + psychotropic treatment group (combined group), for a course of 16 weeks. The West China Psychiatry Association (WCPA) Somatic Symptom Classification Scale (SSCS) was used to evaluate each patient. The levels of hormones in the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-thyroid axes and of blood glucose and glycosylated hemoglobin (HbA1c) were evaluated both before and after treatment. After the treatment, the blood glucose and HbA1c levels in all three groups were lower than those at baseline. Furthermore, the incidence of the abnormal HPA axis in the PT group was significantly decreased (P = 0.003), while the incidence of the abnormal HPA axis in the combined group was 0.0%. The five factor scores of the SSCS in the PT and combined groups after treatment were both significantly low (P < 0.01). Both the incidence of abnormal neuroendocrine axes and SSCS scores in the AT group showed no significant difference before and after treatment. "Blood glucose control + rhythm regulation" should be considered as optimised treatment goals for DM. Moreover, some psychotropics could be used as biorhythm regulators, which have good potential value for clinical application.Clinical trial registration number: ChiCTR1800019064. Name of trial registration: Reinterpretation of mechanism and the optimization of treatment for non-infectious chronic diseases under the "stress-dysrhythmia" theory hypothesis. The full trial protocol can be accessed at the Chinese Clinical Trial Registry ( http://www.chictr.org.cn/ ).

Targeting the Arginine Vasopressin V1b Receptor System and Stress Response in Depression and Other Neuropsychiatric Disorders

A healthy stress response is critical for good mental and overall health and promotes neuronal growth and adaptation, but the intricately balanced biological mechanisms that facilitate a stress response can also result in predisposition to disease when that equilibrium is disrupted. The hypothalamic-pituitary-adrenal (HPA) axis neuroendocrine system plays a critical role in the body's response and adaptation to stress, and vasopressinergic regulation of the HPA axis is critical to maintaining system responsiveness during chronic stress. However, exposure to repeated or excessive physical or emotional stress or trauma can shift the body's stress response equilibrium to a "new normal" underpinned by enduring changes in HPA axis function. Exposure to early life stress due to adverse childhood experiences can also lead to lasting neurobiological changes, including in HPA axis function. HPA axis impairment in patients with depression is considered among the most reliable findings in biological psychiatry, and chronic stress has been shown to play a major role in the pathogenesis and onset of depression and other neuropsychiatric disorders. Modulating HPA axis activity, for example via targeted antagonism of the vasopressin V_1b receptor, is a promising approach for patients with depression and other neuropsychiatric disorders associated with HPA axis impairment. Despite favorable preclinical indications in animal models, demonstration of clinical efficacy for the treatment of depressive disorders by targeting HPA axis dysfunction has been challenging, possibly due to the heterogeneity and syndromal nature of depressive disorders. Measures of HPA axis function, such as elevated cortisol levels, may be useful biomarkers for identifying patients who may benefit from treatments that modulate HPA axis activity. Utilizing clinical biomarkers to identify subsets of patients with impaired HPA axis function who may benefit is a promising next step in fine-tuning HPA axis activity via targeted antagonism of the V_1b receptor.

Re-interpretation of the mechanism of type 2 diabetes mellitus based on a framework of psychosomatic medicine: a real-world study

OBJECTIVE

Using bipolar disorder (BD) as a control, we explored the possible developmental process of impaired glucose metabolism rhythm.

METHODS

In total, 441 subjects (77, 162, 134, 54, and 14 in the pre-diabetes [pre-DM], DM, BD, BD + pre-DM, and BD + DM groups, respectively) and 160 controls were included. All subjects were assessed using the Neuroticism Extraversion Openness Five-Factor Inventory (NEO-FFI). The hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-thyroid (HPT) axes were measured.

RESULTS

Cluster analysis showed that the BD, BD + DM, and DM groups were classified as the 'disease group, the BD + pre-DM group as the 'mixed period group', and the pre-DM group as the 'pre-disease group'. The conscientiousness factor scores of the NEO-FFI in the 'disease group' were higher than the norm but lower than the norm in the 'pre-disease group'. The scores of neurotic factors in the 'pre-disease' and 'mixed period' groups were both significantly higher than that in the 'disease group' (corrected p &lt; 0.001). The incidences of the abnormal HPA axis decreased gradually from the 'pre-disease group' to the 'mixed period group' then to the 'disease group', while those of the HPT axis slightly increased at first and then significantly decreased. The overall prediction rate of the multiple logistic regression model was 92.7%.

CONCLUSION

This study suggests that progression of pre-diabetes to DM is a continuous process from local abnormalities to rhythm disorder of glucose metabolism. This understanding can be applied to the whole course management and early intervention of DM and to the future development of optimised treatment based on rhythm regulation.

TRIAL REGISTRATION

Clinical trial registration number: ChiCTR1800019064. Name of trial registration: Identify and the optimization of treatment for non-infectious chronic diseases under the "stress-dysrhythmia" theory hypothesis (Registration date: 24/10/2018). The full trial protocol can be accessed at the Chinese Clinical Trial Registry ( http://www.chictr.org.cn/ ).

Familial Linkage and Association of the NR3C1 Gene with Type 2 Diabetes and Depression Comorbidity

Impairment in the hypothalamic-pituitary-adrenal (HPA) axis and cortisol pathway may be major contributing factors to the common pathogenesis of major depressive disorders (MDD) and type 2 diabetes (T2D). A significant player in the neuroendocrine HPA axis and cortisol response is the glucocorticoid receptor (GR), which is encoded by the nuclear receptor subfamily 3 group C member (NR3C1) gene. Variants in the NR3C1 gene have been reported in patients with MDD and obesity and found to confer reduced risk for quantitative metabolic traits and T2D in Cushing syndrome; variants have not been reported in T2D and MDD-T2D comorbid patients. We studied 212 original Italian families with a rich family history for T2D and tested 24 single nucleotide polymorphisms (SNPs) in the NR3C1 gene for linkage to and linkage disequilibrium (LD) with T2D and MDD across different inheritance models. We identified a total of 6 novel SNPs significantly linked/in LD to/with T2D (rs6196, rs10482633, rs13186836, rs13184611, rs10482681 and rs258751) and 1 SNP (rs10482668) significantly linked to/in LD with both T2D and MDD. These findings expand understanding of the role that NR3C1 variants play in modulating the risk of T2D-MDD comorbidity. Replication and functional studies are needed to confirm these findings.

Molecular Mechanisms of the Neuroprotective Effect of Methylene Blue

Methylene blue (MB) is the first fully synthetic compound that had found its way into medicine over 120 years ago as a treatment against malaria. MB has been approved for the treatment of methemoglobinemia, but there are premises for its repurposing as a neuroprotective agent based on the efficacy of this compound demonstrated in the models of Alzheimer's, Parkinson's, and Huntington's diseases, traumatic brain injury, amyotrophic lateral sclerosis, depressive disorders, etc. However, the goal of this review was not so much to focus on the therapeutic effects of MB in the treatment of various neurodegeneration diseases, but to delve into the mechanisms of direct or indirect effect of this drug on the signaling pathways. MB can act as an alternative electron carrier in the mitochondrial respiratory chain in the case of dysfunctional electron transport chain. It also displays the anti-inflammatory and anti-apoptotic effects, inhibits monoamine oxidase (MAO) and nitric oxide synthase (NOS), activates signaling pathways involved in the mitochondrial pool renewal (mitochondrial biogenesis and autophagy), and prevents aggregation of misfolded proteins. Comprehensive understanding of all aspects of direct and indirect influence of MB, and not just some of its effects, can help in further research of this compound, including its clinical applications.

Comorbidity of Novel CRHR2 Gene Variants in Type 2 Diabetes and Depression

The corticotropin-releasing hormone receptor 2 (CRHR2) gene encodes CRHR2, contributing to the hypothalamic–pituitary–adrenal stress response and to hyperglycemia and insulin resistance. CRHR2−/− mice are hypersensitive to stress, and the CRHR2 locus has been linked to type 2 diabetes and depression. While CRHR2 variants confer risk for mood disorders, MDD, and type 2 diabetes, they have not been investigated in familial T2D and MDD. In 212 Italian families with type 2 diabetes and depression, we tested 17 CRHR2 single nucleotide polymorphisms (SNPs), using two-point parametric-linkage and linkage-disequilibrium (i.e., association) analysis (models: dominant-complete-penetrance-D1, dominant-incomplete-penetrance-D2, recessive-complete-penetrance-R1, recessive-incomplete-penetrance-R2). We detected novel linkage/linkage-disequilibrium/association to/with depression (3 SNPs/D1, 2 SNPs/D2, 3 SNPs/R1, 3 SNPs/R2) and type 2 diabetes (3 SNPs/D1, 2 SNPs/D2, 2 SNPs/R1, 1 SNP/R2). All detected risk variants are novel. Two depression-risk variants within one linkage-disequilibrium block replicate each other. Two independent novel SNPs were comorbid while the most significant conferred either depression- or type 2 diabetes-risk. Although the families were primarily ascertained for type 2 diabetes, depression-risk variants showed higher significance than type 2 diabetes-risk variants, implying CRHR2 has a stronger role in depression-risk than type 2 diabetes-risk. In silico analysis predicted variants’ dysfunction. CRHR2 is for the first time linked to/in linkage-disequilibrium/association with depression-type 2 diabetes comorbidity and may underlie the shared genetic pathogenesis via pleiotropy.

Implication of Melanocortin Receptor Genes in the Familial Comorbidity of Type 2 Diabetes and Depression

The melanocortin receptors are G-protein-coupled receptors, which are essential components of the hypothalamic–pituitary–adrenal axis, and they mediate the actions of melanocortins (melanocyte-stimulating hormones: α-MSH, β-MSH, and γ-MSH) as well as the adrenocorticotropin hormone (ACTH) in skin pigmentation, adrenal steroidogenesis, and stress response. Three melanocortin receptor genes (MC1R, MC2R, and MC5R) contribute to the risk of major depressive disorder (MDD), and one melanocortin receptor gene (MC4R) contributes to the risk of type 2 diabetes (T2D). MDD increases T2D risk in drug-naïve patients; thus, MDD and T2D commonly coexist. The five melanocortin receptor genes might confer risk for both disorders. However, they have never been investigated jointly to evaluate their potential contributing roles in the MDD-T2D comorbidity, specifically within families. In 212 Italian families with T2D and MDD, we tested 11 single nucleotide polymorphisms (SNPs) in the MC1R gene, 9 SNPs in MC2R, 3 SNPs in MC3R, 4 SNPs in MC4R, and 2 SNPs in MC5R. The testing used 2-point parametric linkage and linkage disequilibrium (LD) (i.e., association) analysis with four models (dominant with complete penetrance (D1), dominant with incomplete penetrance (D2), recessive with complete penetrance (R1), and recessive with incomplete penetrance (R2)). We detected significant (p ≤ 0.05) linkage and/or LD (i.e., association) to/with MDD for one SNP in MC2R (rs111734014) and one SNP in MC5R (rs2236700), and to/with T2D for three SNPs in MC1R (rs1805007 and rs201192930, and rs2228479), one SNP in MC2R (rs104894660), two SNPs in MC3R (rs3746619 and rs3827103), and one SNP in MC4R genes (Chr18-60372302). The linkage/LD/association was significant across different linkage patterns and different modes of inheritance. All reported variants are novel in MDD and T2D. This is the first study to report risk variants in MC1R, MC2R, and MC3R genes in T2D. MC2R and MC5R genes are replicated in MDD, with one novel variant each. Within our dataset, only the MC2R gene appears to confer risk for both MDD and T2D, albeit with different risk variants. To further clarity the role of the melanocortin receptor genes in MDD-T2D, these findings should be sought among other ethnicities as well.

A Systematic Review and Meta-Analysis of the Prevalence and Risk Factors of Depression in Type 2 Diabetes Patients in China

Background

The prevalence of type 2 diabetes mellitus (T2DM) is increasing in China. Depression in patients with T2DM interferes with blood glucose management, leads to poor treatment outcomes, and has a high risk of dementia and cardiovascular event. We conducted this systematic review and meta-analysis to evaluate the prevalence of depression in patients with T2DM in China and explore potential risk factors associated with depression in T2DM.

Methods

We conducted a literature search in MEDLINE/PubMed, EMBASE, the Cochrane Library, the Chinese Biomedical Literature Database (CBM), the China National Knowledge Infrastructure (CNKI), the Chinese Science and Technology Periodical Database (VIP), and the Wanfang Database from their inception to February 25, 2022 to include population-based, cross-sectional surveys that investigated the prevalence of depression in Chinese T2DM patients and studied possible risk factors. Gray literature and reference lists were also manually searched. We used the Agency for Healthcare Research and Quality methodology checklist to assess the risk of bias in the included studies. Two reviewers screened studies, extracted data, and evaluated the risk of bias independently. The primary outcome was the pooled prevalence of depression in Chinese T2DM patients, and the secondary outcomes included potential risk factors for depression in T2DM patients. R (version 3.6.1) and Stata (version 12.0) software were used for data synthesis.

Results

We included 48 reports that identified 108,678 subjects. Among the included reports, 4 were rated as low risk of bias, 40 moderate risks of bias, and 4 high risks of bias. The prevalence of depression in T2DM patients in China was 25.9% (95% CI 20.6%-31.6%). The prevalence of depression was higher in women (OR = 1.36, 95% CI 1.19-1.54), subjects ≥60 years (OR = 1.56, 95% CI 1.14-2.14), with a primary school or lower education (vs. middle or high school education (OR = 1.49, 95% CI 1.16 - 1.92); vs. college degree or higher education (OR = 1.84, 95% CI 1.16 - 2.92), with a duration of T2DM ≥ 10 years (OR = 1.68, 95% CI 1.11-2.54), with complications (OR = 1.90, 95% CI 1.53-2.36), insulin users (OR = 1.46, 95% CI 1.09-1.96) and individuals living alone (OR = 2.26, 95% CI 1.71-2.98). T2DM patients with current alcohol use had a lower prevalence of depression (OR = 0.70, 95% CI 0.58-0.86). Prevalence varied from 0.8 to 52.6% according to different instruments used to detect depression.

Conclusion

The prevalence of depression in T2DM patients is remarkable in China. Potential risk factors of depression in T2DM patients included women, age ≥ 60 years, low educational level, complications, duration of diabetes ≥ 10 years, insulin use, and living alone. High-quality epidemiological investigations on the prevalence of depression in Chinese T2DM patients are needed to better understand the status of depression in T2DM.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42020182979.

Genetics and antiepileptic mood stabilizer treatment response in bipolar disorder: what do we know?

Antiepileptic mood stabilizers (AED-MS) are often used to treat bipolar disorder (BD). Similar to other mood disorder medications, AED-MS treatment response varies between patients. Identification of biomarkers associated with treatment response may ultimately help with the delivery of individualized treatment and lead to improved treatment efficacy. Here, we conducted a narrative review of the current knowledge of the pharmacogenomics of AED-MS (valproic acid, lamotrigine and carbamazepine) treatment response in BD, including genetic contributions to AED-MS pharmacokinetics. Genes involved in neurotransmitter systems and drug transport have been shown to be associated with AED-MS treatment response. As more studies are conducted, and experimental and analytical methods advance, knowledge of AED-MS pharmacogenomics is expected to grow and contribute to precision medicine in BD.

Rhythm of Fetoplacental 11β-Hydroxysteroid Dehydrogenase Type 2 - Fetal Protection From Morning Maternal Glucocorticoids

CONTEXT

Excess glucocorticoids impact fetal health. Maternal glucocorticoids peak in early morning. Fetoplacental 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) inactivates cortisol to cortisone, protecting the fetus from high glucocorticoids. However, time-specific alterations of human fetoplacental 11β-HSD2 have not been studied.

OBJECTIVE

We hypothesized that fetoplacental 11β-HSD2 activity shows time-specific alteration and acute affective or anxiety disorders impact fetoplacental 11β-HSD2 activity.

METHODS

In this observational study we investigated 78 pregnant European women undergoing amniocentesis (15.9 ± 0.9 weeks of gestation). Amniotic fluid was collected (8:00 to 16:30 hours) for analysis of fetoplacental 11β-HSD2 activity, using cortisol (F):cortisone (E) ratio in amniotic fluid, E/(E + F). Fetoplacental 11β-HSD2 rhythm and association with "acute affective or anxiety disorder" (patients with at least one of: a major depressive episode, specific phobia, panic disorder, generalized anxiety disorder, mixed anxiety and depressive disorder) and "acute anxiety disorder" (one of: panic disorder, generalized anxiety disorder, mixed anxiety, depressive disorder), assessed using Mini International Neuropsychiatric Interview, were investigated.

RESULTS

Activity of 11β-HSD2 correlated with time of amniocentesis, peaking in the morning (r = -0.398; P < 0.001) and increased with acute affective or anxiety disorder (mean [M] = 0.70 vs M = 0.74; P = 0.037) and acute anxiety disorder (M = 0.70 vs M = 0.75; P = 0.016). These associations remained significant when controlling for confounders. 11β-HSD2 activity correlated negatively with pre-pregnancy body mass index (r = -0.225; P = 0.047).

CONCLUSION

Our study indicates a time-specific alteration of fetoplacental 11β-HSD2 activity with peaking levels in the morning, demonstrating a mechanism of fetal protection from the morning maternal glucocorticoid surge.

A Comprehensive Analysis of Unique and Recurrent Copy Number Variations in Alzheimer's Disease and its Related Disorders

BACKGROUND

Copy number variations (CNVs) play an important role in the genetic etiology of various neurological disorders, including Alzheimer's disease (AD). Type 2 diabetes mellitus (T2DM) and major depressive disorder (MDD) were shown to have share mechanisms and signaling pathways with AD.

OBJECTIVE

We aimed to assess CNVs regions that may harbor genes contributing to AD, T2DM, and MDD in 67 Saudi familial and sporadic AD patients, with no alterations in the known genes of AD and genotyped previously for APOE.

METHODS

DNA was analyzed using the CytoScan-HD array. Two layers of filtering criteria were applied. All the identified CNVs were checked in the Database of Genomic Variants (DGV).

RESULTS

A total of 1086 CNVs (565 gains and 521 losses) were identified in our study. We found 73 CNVs harboring genes that may be associated with AD, T2DM or MDD. Nineteen CNVs were novel. Most importantly, 42 CNVs were unique in our studied cohort existing only in one patient. Two large gains on chromosomes 1 and 13 harbored genes implicated in the studied disorders. We identified CNVs in genes that encode proteins involved in the metabolism of amyloid-β peptide (AGRN, APBA2, CR1, CR2, IGF2R, KIAA0125, MBP, RER1, RTN4R, VDR and WISPI) or Tau proteins (CACNAIC, CELF2, DUSP22, HTRA1 and SLC2A14).

CONCLUSION

The present work provided information on the presence of CNVs related to AD, T2DM, and MDD in Saudi Alzheimer's patients.

Elevated Circulating LINC-P21 Serves as a Diagnostic Biomarker of Type 2 Diabetes Mellitus and Regulates Pancreatic β-cell Function by Sponging miR-766-3p to Upregulate NR3C2

OBJECTIVE

The purpose of this study was to evaluate the clinical value and biological function of long non-coding RNA (lncRNA) LINC-P21 in type 2 diabetes mellitus (T2DM), and explore the underlying mechanisms.

METHODS

The expression of LINC-P21 was estimated using quantitative real-time PCR. The functional role of LINC-P21 was explored by gain- and loss-of-function experiments. INS-1 cell proliferation was analyzed using a cell counting kit-8 (CCK-8)assay, and the glucose-stimulated insulin secretion was measured using an ELISA kit. The miRNAs that might be sponged by LINC-P21 were analyzed, and the subsequent target genes were predicted and assessed in INS-1 cells.

RESULTS

Serum expression of LINC-P21 was elevated in T2DM patients, which was correlated with fasting blood glucose levels and disease diagnosis. The glucose-stimulated insulin secretion and the proliferation of INS-1 cells were enhanced by LINC-P21 knockdown, but the overexpression of LINC-P21 led to opposite effects. miR-766-3p could be directly inhibited by LINC-P21 in INS-1 cells and reverse the effects of LINC-P21 on β-cell function. Additionally, NR3C2 was determined as a target of miR-766-3p, which could be positively regulated by LINC-P21 and had same effects with LINC-P21 on INS-1 cell proliferation and insulin secretion.

CONCLUSION

All the data demonstrated that serum elevated LINC-P21 and decreased miR-766-3p serve as candidate diagnostic biomarkers in T2DM patients. LINC-P21 acts as a potential regulator in insulin secretion and proliferation of pancreatic β-cells through targeting miR-766-3p to upregulate NR3C2.

Clinical Evidence of Antidepressant Effects of Insulin and Anti-Hyperglycemic Agents and Implications for the Pathophysiology of Depression-A Literature Review

Close connections between depression and type 2 diabetes (T2DM) have been suggested by many epidemiological and experimental studies. Disturbances in insulin sensitivity due to the disruption of various molecular pathways cause insulin resistance, which underpins many metabolic disorders, including diabetes, as well as depression. Several anti-hyperglycemic agents have demonstrated antidepressant properties in clinical trials, probably due to their action on brain targets based on the shared pathophysiology of depression and T2DM. In this article, we review reports of clinical trials examining the antidepressant effect of these medications, including insulin, metformin, glucagon like peptide-1 receptor agonists (GLP-1RA), and peroxisome proliferator-activated receptor (PPAR)-γ agonists, and briefly consider possible molecular mechanisms underlying the associations between amelioration of insulin resistance and improvement of depressive symptoms. In doing so, we intend to suggest an integrative perspective for understanding the pathophysiology of depression.

Association of FKBP5 genotype with depressive symptoms in patients with coronary heart disease: a prospective study

Depression and coronary heart disease (CHD) are prevalent and often co-occurring disorders. Both have been associated with a dysregulated stress system. As a central element of the stress system, the FKBP5 gene has been shown to be associated with depression. In a prospective design, this study aims to investigate the association of FKBP5 with depressive symptoms in CHD patients. N = 268 hospitalized CHD patients were included. Depressive symptoms were measured using the Hospital Anxiety and Depression Scale (HADS-D) at four time points (baseline, and after 1 month, 6 months, and 12 months). The functional FKBP5 single-nucleotide polymorphism (SNP) rs1360780 was selected for genotyping. Linear regression models showed that a higher number of FKBP5 C alleles was associated with more depressive symptoms in CHD patients both at baseline (p = 0.015) and at 12-months follow-up (p = 0.025) after adjustment for confounders. Further analyses revealed that this effect was driven by an interaction of FKBP5 genotype with patients’ prior CHD course. Specifically, only in patients with a prior myocardial infarction or coronary revascularization, more depressive symptoms were associated with a higher number of C alleles (baseline: p = 0.046; 1-month: p = 0.026; 6-months: p = 0.028). Moreover, a higher number of C alleles was significantly related to a greater risk for dyslipidemia (p = .016). Our results point to a relevance of FKBP5 in the association of the two stress-related diseases depression and CHD.

Shared (epi)genomic background connecting neurodegenerative diseases and type 2 diabetes

The progressive aging of populations has resulted in an increased prevalence of chronic pathologies, especially of metabolic, neurodegenerative and movement disorders. In particular, type 2 diabetes (T2D), Alzheimer’s disease (AD) and Parkinson’s disease (PD) are among the most prevalent age-related, multifactorial pathologies that deserve particular attention, given their dramatic impact on patient quality of life, their economic and social burden as well the etiopathogenetic mechanisms, which may overlap in some cases. Indeed, the existence of common triggering factors reflects the contribution of mutual genetic, epigenetic and environmental features in the etiopathogenetic mechanisms underlying T2D and AD/PD. On this subject, this review will summarize the shared (epi)genomic features that characterize these complex pathologies. In particular, genetic variants and gene expression profiles associated with T2D and AD/PD will be discussed as possible contributors to determine the susceptibility and progression to these disorders. Moreover, potential shared epigenetic modifications and factors among T2D, AD and PD will also be illustrated. Overall, this review shows that findings from genomic studies still deserves further research to evaluate and identify genetic factors that directly contribute to the shared etiopathogenesis. Moreover, a common epigenetic background still needs to be investigated and characterized. The evidences discussed in this review underline the importance of integrating large-scale (epi)genomic data with additional molecular information and clinical and social background in order to finely dissect the complex etiopathogenic networks that build up the “disease interactome” characterizing T2D, AD and PD.

Atorvastatin ameliorates depressive behaviors and neuroinflammatory in streptozotocin-induced diabetic mice

Depression is a chronic and progressive syndrome and commonly associated with several neuropsychiatric comorbidities, of which depression is the most studied. It has been demonstrated that statins also have anti-inflammatory and immunomodulatory properties, which being explored for potential benefits in depression. However, the role of statins in the treatment of diabetes-related depression has not been well examined. Herein, we investigated the effects of atorvastatin on depressive behaviors and neuroinflammation in streptozotocin-induced diabetic mice. Our data indicated that oral administration of atorvastatin at 10 or 20 mg/kg for 3 weeks markedly ameliorated diabetes-associated depressive behaviors reflected by better performance in sucrose preference test (SPT), tail suspension test (TST), and novelty-suppressed feeding test (NSFT). The study further showed that atrovastatin decreased the expression of nucleus NF-κB p65 expression and ameliorated neuroinflammatory responses in prefrontal cortex as evidenced by less Iba-1-positive cells and lower inflammatory mediators including IL-1β and TNF-α. As expected, atorvastatin-treated diabetic mice exhibited significant improvement of hyperlipidemia rather than hyperglycemia. These results suggest that atorvastatin has the potential to be employed as a therapy for diabetes-related depression.

The Importance of DS-14 and HADS Questionnaires in Quantifying Psychological Stress in Type 2 Diabetes Mellitus

Background and Objectives: The comorbid association between type 2 diabetes mellitus (T2DM) and a psychological profile characterized by depression and/or anxiety has been reported to increase the risk of coronary heart disease (CAD), the most striking macrovascular complication of diabetes. The purpose of the present study was to quantify anxiety, depression and the presence of type D personality, and to correlate the scores obtained with cardiovascular risk factors and disease severity in diabetic patients. Materials and methods: The retrospective study included 169 clinically stable diabetic patients divided into two groups: group 1 without macrovascular complications (n = 107) and group 2 with CAD, stroke and/or peripheral vascular disease (n = 62). A biochemical analysis and an assessment of psychic stress by applying the Hospital Anxiety and Depression Scale (HADS)and the Type D scale (DS-14) to determine anxiety, depression and D personality scores were done in all patients. Statistical analysis was made using SPSSv17 and Microsoft Excel, non-parametric Kruskal-Wallis and Mann-Whitney tests. Results: Following application of the HAD questionnaire for the entire group (n = 169), anxiety was present in 105 patients (62.2%), and depression in 96 patients (56.8%). Group 2 showed significantly higher anxiety scores compared to group 1 (p = 0.014), while depression scores were not significantly different. Per entire group, analysis of DS-14 scores revealed social inhibition (SI) present in 56 patients (33%) and negative affectivity (NA) in 105 patients (62%). TheDS-14 SI score was significantly higher in group 2 compared to group 1 (p = 0.036). Type D personality, resulting from scores above 10 in both DS-14 parameter categories, was present in 51 patients of the study group (30%). There was a direct and significant correlation (r = 0.133, p = 0.025) between the Hospital Anxiety and Depression Scale-Anxiety (HAD-A) score and the LDL-c values. Conclusions: The results of this study demonstrated that more than a half of patients with diabetes had anxiety and/or depression and one third had Type D personality, sustaining that monitoring of emotional state and depression should be included in the therapeutic plan of these patients. New treatment strategies are needed to improve the well-being of diabetic patients with psychological comorbidities.

Neuroendocrine drivers of risk and resilience: The influence of metabolism & mitochondria

The manifestation of risk versus resilience has been considered from varying perspectives including genetics, epigenetics, early life experiences, and type and intensity of the challenge with which the organism is faced. Although all of these factors are central to determining risk and resilience, the current review focuses on what may be a final common pathway: metabolism. When an organism is faced with a perturbation to the environment, whether internal or external, appropriate energy allocation is essential to resolving the divergence from equilibrium. This review examines the potential role of metabolism in the manifestation of stress-induced neural compromise. In addition, this review details the current state of knowledge on neuroendocrine factors which are poised to set the tone of the metabolic response to a systemic challenge. The goal is to provide an essential framework for understanding stress in a metabolic context and appreciation for key neuroendocrine signals.

Co-shared genetics and possible risk gene pathway partially explain the comorbidity of schizophrenia, major depressive disorder, type 2 diabetes, and metabolic syndrome

Schizophrenia (SCZ) and major depressive disorder (MDD) in treatment-naive patients are associated with increased risk for type 2 diabetes (T2D) and metabolic syndrome (MetS). SCZ, MDD, T2D, and MetS are often comorbid and their comorbidity increases cardiovascular risk: Some risk genes are likely co-shared by them. For instance, transcription factor 7-like 2 (TCF7L2) and proteasome 26S subunit, non-ATPase 9 (PSMD9) are two genes independently reported as contributing to T2D and SCZ, and PSMD9 to MDD as well. However, there are scarce data on the shared genetic risk among SCZ, MDD, T2D, and/or MetS. Here, we briefly describe T2D, MetS, SCZ, and MDD and their genetic architecture. Next, we report separately about the comorbidity of SCZ and MDD with T2D and MetS, and their respective genetic overlap. We propose a novel hypothesis that genes of the prolactin (PRL)-pathway may be implicated in the comorbidity of these disorders. The inherited predisposition of patients with SCZ and MDD to psychoneuroendocrine dysfunction may confer increased risk of T2D and MetS. We illustrate a strategy to identify risk variants in each disorder and in their comorbid psychoneuroendocrine and mental-metabolic dysfunctions, advocating for studies of genetically homogeneous and phenotype-rich families. The results will guide future studies of the shared predisposition and molecular genetics of new homogeneous endophenotypes of SCZ, MDD, and metabolic impairment.

Relationship between Meditation and Waking Salivary Cortisol Secretion among Long-Term MBSR Instructors

Background: A potential relationship between long-term meditation practice and stress reduction remains virtually unexplored. The purpose of this study was to characterize stress using salivary waking cortisol in a group of long-term meditators with training in the Mindfulness-Based Stress Reduction (MBSR) program. Materials and Methods: Four salivary cortisol samples were collected from meditators (n = 84) during the first hour of awakening. The waking cortisol rhythm was summarized using cortisol area under the curve (AUC) with respect to increased secretion above baseline (AUCI) and cortisol AUC above ground (above zero, AUCG); data on meditation duration and depth, perceived stress, and other covariates were collected via self-reported questionnaire. Results: Individuals in the highest quartile of years meditating (> 26 years) had statistically significantly elevated AUCG values (p = 0.01) as compared to individuals in the lowest quartile of years meditating (≤10 years). This relationship was more pronounced among individuals waking at or before 6: 30 a.m. Conclusions: Overall, an increasing number of years of meditation practice was related to a higher waking cortisol response. These intriguing findings warrant additional exploration, as the stress response can be complex.

Effect of lethal yellow (AY) mutation and photoperiod alterations on mouse behavior

Decrease in natural illumination in fall/winter months causes depressive-like seasonal affective disorders in vulnerable individuals. Obesity is another risk factor of depression. The lethal yellow (AY) mutation causes ectopic expression of agouti protein in the brain. Mice heterozygous for AY mutation (AY/a) are obese compared to their wild-type littermates (a/a). The main aims of the study were to investigate the effects of AY mutation, photoperiod and the interaction between these factors on daily activity dynamics, feeding, locomotor and exploratory activities, anxiety-related and depressive-like behaviors in mild stress condition. Six weeks old mouse males of AY/a and a/a lines were divided into four groups eight animals each and exposed to long- (14 h light and 10 h darkness) or short- (4 h light and 20 h darkness) day conditions for 28 days. Then the behavior of these mice was successively investigated in the home cage, open field, elevated plus-maze and forced swim tests. We did not observed any effect of AY mutation on the general activity, water and food consumption in the home cage; locomotion and exploration in the open field test; anxiety-related behavior in the open field and elevated plus-maze tests. At the same time, AY mutation increased depressive-like immobility time in the forced swim test (F1.28 = 20.03, p = 0.00012). Shortday conditions decreased nocturnal activity in the home cage, as well as locomotion (F1.28 = 16.33, p = 0.0004) and exploration (F1.28 = 16.24, p < 0.0004) in the open field test. Moreover, short-day exposition decreased time spent in the center of the open field (F1.28 = 6.57, p = 0.016) and in the open arms of the elevated plus-maze (F1.28 = 12.08, p = 0.0017) tests and increased immobility time in the forced swim test (F1.28 = 9.95, p = 0.0038). However, no effect of the interaction between AY mutation and photoperiod on immobility time in the forced swim test was observed. Therefore, short-day photoperiod and AY mutation increased depressive-like behavior in the forced swim test by means of different mechanisms.

Both Basal and Acute Restraint Stress-Induced c-Fos Expression Is Influenced by Age in the Extended Amygdala and Brainstem Stress Centers in Male Rats

The hypothalamus-pituitary-adrenal axis (HPA) is the main regulator of the stress response. The key of the HPA is the parvocellular paraventricular nucleus of the hypothalamus (pPVN) controlled by higher-order limbic stress centers. The reactivity of the HPA axis is considered to be a function of age, but to date, little is known about the background of this age-dependency. Sporadic literature data suggest that the stress sensitivity as assessed by semi-quantitation of the neuronal activity marker c-Fos may also be influenced by age. Here, we aimed at investigating the HPA activity and c-Fos immunoreactivity 2 h after the beginning of a single 60 min acute restraint stress in eight age groups of male Wistar rats. We hypothesized that the function of the HPA axis (i.e., pPVN c-Fos and blood corticosterone (CORT) level), the neuronal activity of nine stress-related limbic areas (i.e., magnocellular PVN (mPVN), medial (MeA), central (CeA), basolateral nuclei of the amygdala, the oval (ovBNST), dorsolateral (dlBNST), dorsomedial (dmBNST), ventral and fusiform (fuBNST) divisions of the bed nucleus of the stria terminalis (BNST)), and two brainstem stress centers such as the centrally projecting Edinger-Westphal nucleus (cpEW) and dorsal raphe nucleus (DR) show age dependency in their c-Fos response. The somatosensory barrel cortex area (S1) was evaluated to test whether the age dependency is specific for stress-centers. Our results indicate that the stress-induced rise in blood CORT titer was lower in young age reflecting relatively low HPA activity. All 12 stress-related brain areas showed c-Fos response that peaked at 2 months of age. The magnitude of c-Fos immunoreactivity correlated negatively with age in seven regions (MeA, CeA, ovBNST, dlBNST, dmBNST, fuBNST and pPVN). Unexpectedly, the CeA, ovBNST and cpEW showed a considerable basal c-Fos expression in 1-month-old rats which decreased with age. The S1 showed a U-shaped age-related dynamics in contrast to the decline observed in stress centers. We conclude that the age- and brain area dependent dynamics in stress-induced neuronal activity pattern may contribute to the age dependance of the stress reactivity. Further studies are in progress to determine the neurochemical identity of neurons showing age-dependent basal and/or stress-induced c-Fos expression.

Type 2 diabetes and cardiometabolic risk may be associated with increase in DNA methylation of FKBP5

Background

Subclinical hypercortisolism and hypothalamic-pituitary-adrenal (HPA) axis dysfunction are associated with type 2 diabetes (T2DM), cardiovascular disease, and metabolic dysfunction. Intronic methylation of FKBP5 has been implicated as a potential indicator of chronic cortisol exposure. Our overall objective in this study was to determine the association of chronic cortisol exposure, measured via percent methylation of FKBP5 at intron 2, with percent glycosylated hemoglobin (HbA1c), low-density lipoprotein cholesterol (LDL-cholesterol), waist circumference (WC), and body mass index (BMI), in a clinic-based sample of 43 individuals with T2DM.

Results

Greater percent methylation of the FKBP5 intron 2 at one CpG-dinucleotide region was significantly associated with higher HbA1c (β = 0.535, p = 0.003) and LDL cholesterol (β = 0.344, p = 0.037) and a second CpG-dinucleotide region was significantly associated with higher BMI and WC (β = 0.516, p = 0.001; β = 0.403, p = 0.006, respectively).

Conclusions

FKBP5 methylation may be a marker of higher metabolic risk in T2DM, possibly secondary to higher exposure to cortisol. Further work should aim to assess the longitudinal association of FKBP5 with cardiovascular disease and glycemic outcomes in T2DM as a first step in understanding potential preventive and treatment-related interventions targeting the HPA axis.

Ablation of somatostatin cells leads to impaired pancreatic islet function and neonatal death in rodents

The somatostatin (SST)-secreting cells were mainly distributed in the pancreatic islets, brain, stomach and intestine in mammals and have many physiological functions. In particular, the SST-secreting δ cell is the third most common cell type in the islets of Langerhans. Recent studies have suggested that dysregulation of paracrine interaction between the pancreatic δ cells and β cells results in impaired glucose homeostasis and contributes to diabetes development. However, direct evidence of the functional importance of SST cells in glucose homeostasis control is still lacking. In the present study, we specifically ablated SST-secreting cells by crossing Sst-cre transgenic mice with R26 ^DTA mice (Sst ^Cre R26 ^DTA ). The Sst ^Cre R26 ^DTA mice exhibited neonatal death. The life spans of these mice with severe hypoglycemia were extended by glucose supplementation. Moreover, we observed that SST cells deficiency led to increased insulin content and excessive insulin release, which might contribute to the observed hypoglycemia. Unexpectedly, although SST is critical for the regulation of insulin content, factors other than SST that are produced by pancreatic δ cells via their endogenous corticotropin-releasing hormone receptor 2 (CRHR2) activity play the main roles in maintaining normal insulin release, as well as neonatal glucose homeostasis in the resting state. Taken together, our results identified that the SST cells in neonatal mouse played critical role in control of insulin release and normal islet function. Moreover, we provided direct in vivo evidence of the functional importance of the SST cells, which are essential for neonatal survival and the maintenance of glucose homeostasis.

The Bidirectional Relationship between Diabetes and Depression: A Literature Review

Diabetes is a major public health problem worldwide. Depression is a serious mental condition that decreases mental and physical functioning and reduces the quality of life. Several lines of evidence suggest a bidirectional relationship between diabetes and depression: diabetes patients are twice as likely to experience depression than nondiabetic individuals. In contrast, depression increases the risk of diabetes and interferes with its daily self-management. Diabetes patients with depression have poor glycemic control, reduced quality of life, and an increased risk of diabetes complications, consequently having an increased mortality rate. Conflicting evidence exists on the potential role of factors that may account for or modulate the relationship between diabetes and depression. Therefore, this review aims to highlight the most notable body of literature that dissects the various facets of the bidirectional relationship between diabetes and depression. A focused discussion of the proposed mechanisms underlying this relationship is also provided. We systematically reviewed the relevant literature in the PubMed database, using the keywords “Diabetes AND Depression”. After exclusion of duplicate and irrelevant material, literature eligible for inclusion in this review was based on meta-analysis studies, clinical trials with large sample sizes (n≥1,000), randomized clinical trials, and comprehensive national and cross-country clinical studies. The evidence we present in this review supports the pressing need for long, outcome-oriented, randomized clinical trials to determine whether the identification and treatment of patients with these comorbid conditions will improve their medical outcomes and quality of life.

Conditions Associated with Essential Tremor in Veterans: A Potential Role for Chronic Stress

Background

Increased depression, hearing loss, dementia, alcoholism, and mortality in essential tremor patients remain unexplained. We investigated whether conditions associated with tremor are linked to chronic stress.

Methods

The FY2013 Veterans Affairs database was queried for 38 selected dual diagnosis combinations in 5,854,223 veterans aged 21–95 years.

Results

Post-traumatic stress disorder, anxiety, and depression were the most common psychiatric diagnoses in tremor patients, with the odds ratio exceeding 2 in all 15-year cohorts. Depending on age, patients with essential tremor were more likely than those without to have obsessive–compulsive disorder, bipolar illness, schizophrenia, use tobacco and abuse alcohol, have hypertension, obesity, hyperlipidemia, diabetes, vitamin D deficiency, coronary and cerebrovascular diseases, congestive heart failure, stroke, asthma, hypothyroidism, irritable bowel syndrome, renal insufficiency, alcoholic liver disease, hearing loss, glaucoma, macular degeneration, migraine, epilepsy, idiopathic polyneuropathy, history of head trauma, and ‘Alzheimer’s dementia. In contrast, lung and colorectal cancer, amyotrophic lateral sclerosis, psychostimulant abuse, and rheumatoid arthritis were not more common.

Discussion

Post-traumatic stress disorder, anxiety, and depression, strongly associated with essential tremor, are known risk factors for poor health habits, tobacco use and alcohol abuse; collectively these are risk factors for vascular disease, with further negative health consequences for multiple organ systems. As essential tremor is associated with all these conditions, we propose that chronic stress is not only responsible for the conditions associated with tremor but in some cases itself directly and indirectly induces essential tremor, so that tremor and poor health share a common cause.

Association of Established Thyroid-stimulating Hormone and Free Thyroxine Genetic Variants with Hashimoto's Thyroiditis

Hashimoto's thyroiditis (HT), the most frequent autoimmune thyroid disease (AITD), is characterized by chronic inflammation of the thyroid gland that usually results in hypothyroidism. Thyroid-stimulating hormone (TSH) and free thyroxine (FT4) levels are used as clinical determinants of thyroid function. The main aim of this study was to explore the association of established TSH and FT4 genetic variants with HT. We performed a case-control analysis using 23 genetic markers in 200 HT patients and 304 controls. Additionally, we tested the association of selected variants with several thyroid-related quantitative traits in HT cases only. Two genetic variants showed nominal association with HT: rs11935941 near NR3C2 gene (p = 0.0034, OR = 0.57, 95% CI = 0.39-0.83) and rs1537424 near MBIP gene (p = 0.0169, OR = 0.72, 95% CI = 0.55-0.94). Additionally, three SNPs showed nominal association with thyroglobulin antibody (TgAb) levels: rs4804416 in INSR gene (p = 0.0073, β = -0.51), rs6435953 near IGFBP5 gene (p = 0.0081, β = 0.75), and rs1537424 near MBIP gene (p = 0.0117, β = 0.49). GLIS3 genetic variant rs10974423 showed nominal association with thyroid peroxidase antibody (TPOAb) levels (p = 0.0465, β = -0.56) and NRG1 genetic variant rs7825175 was nominally associated with thyroid gland volume (p = 0.0272, β = -0.18). All detected loci were previously related to thyroid function or pathology. Findings from our study suggest biological relevance of NR3C2 and MBIP with HT, although these loci require additional confirmation in a larger replication study.

CHRONIC UNPREDICTABLE MILD STRESS PROGRESSIVELY DISTURBS GLUCOSE METABOLISM AND APPETITE HORMONES IN RATS

Context

Chronic stress is characterized by increased release of catecholamines, glucocorticoids and other neurohumoral factors, predisposing individuals to obesity, insulin resistance and vascular disease, pathologies considered priority health problems. Study of alterations induced by stress on metabolism in association with food intake modulatory hormones (insulin, leptin and ghrelin) is mandatory.

Objective

This research studied temporal course during 60 days of chronic unpredictable mild stress (CUMS) on glucose and lipids metabolism, and on the neuroendocrine system that regulates appetite-satiety balance.

Materials and Methods

Wistar rats were exposed to CUMS for 20, 40 and 60 days. Corticosterone stayed high during 60 days of CUMS; after 40 days, body weight, cholesterol and triglycerides decreased and glucose intolerance was evident at day 60; insulin and ghrelin increased at 20 and 40 days, respectively; leptin decreased after day 20. Data suggest that 60 days of CUMS progressively disturb metabolism of carbohydrates and lipids as well as food intake regulatory hormones, affecting the metabolism, and can lead to the development of chronic degenerative diseases, such as cardiovascular disease, metabolic syndrome and type 2 diabetes.

Increased prevalence of depression and anxiety among subjects with metabolic syndrome and known type 2 diabetes mellitus - a population-based study

OBJECTIVES

The metabolic syndrome (MetS) is a cluster of cardiovascular risk factors associated with high cardiovascular morbidity and mortality. The MetS and its elements have been linked to anxiety and depressive disorders. The aim of the current cross-sectional study was to assess the prevalence of depression and anxiety, measured by the Zung Self-Rating Scale in subjects with and without the metabolic syndrome and diabetes.

METHODS

A total of 2111 adults were included, 1155 female, age 47.6 (13.7) and 956 male, age 45.2 (13.5). All participants filled questionnaires covering current and past disorders and medication, smoking and family history. Zung self-rating depression and anxiety scales were completed. Body weight, height and waist circumference were measured, BMI was calculated, serum glucose and lipids were measured.

RESULTS

Depression (SDSi) and anxiety scores (SASi) were higher in the females and increased with age (p < 0.001). SDSi was higher in the females and males with metabolic syndrome (MetS) (50.9 ± 9.8 vs. 45.9 ± 8.9, p < 0.001 and 42.7 ± 9.2 vs. 40.5 ± 7.9 p < 0.001, respectively). SASi was higher in the MetS subjects (females 50.59 ± 11.35 vs. 45.97 ± 10.58, p < 0.001; males 40.48 ± 10.1 vs. 38.04 ± 8.42, p < 0.001). Both SDSi and SASi were higher in the subjects with known diabetes than in those with normal glucose tolerance (Mann-Whitney both p < 0,001). Positive depressive scores were more prevalent in subjects with MetS than those without (females 54% vs. 31.6%, p < 0.001; males 22.7% vs. 12.3%, p < 0.001). Depression and anxiety were more prevalent in the subjects with known diabetes than in those with normal glucose tolerance but not in the newly-diagnosed diabetes. The OR for depressiveness was 2.0 (1.3; 2.6) in subjects with MetS and 4.2 (2.3; 7.8) in those with known diabetes.

CONCLUSIONS

In conclusion, depressiveness and anxiety were associated positively with age and female gender and were more prevalent among subjects with MetS and known diabetes mellitus.

Modeling the Sex Differences and Interindividual Variability in the Activity of the Hypothalamic-Pituitary-Adrenal Axis

Significant sex differences exist in the activity of the hypothalamic-pituitary-adrenal (HPA) axis. These differences are thought to contribute to the disparity in the prevalence of various autoimmune and infectious diseases between males and females. We used a mathematical model of the HPA axis to evaluate the hypothesis that differential sensitivity and negative feedback of the HPA axis network are causal factors for the observed sex differences in its activity. In doing so, we implicitly accounted for the differential influence of gonadal hormones on the HPA axis. Furthermore, we determined whether the putative mechanisms responsible for differences in basal HPA axis activity might also contribute to the observed differences in its stimulus-driven response. Model simulations predicted that the female HPA axis has greater adrenal sensitivity and weaker negative feedback. We identified two distinct sex-specific parameter spaces that generate corticosterone profiles in qualitative agreement with experimental results. We propose that these parameter subspaces indicate the interindividual variability in the regulatory mechanisms of the HPA axis. Furthermore, the model predicts that the maintenance of homeostatic rhythms in response to chronic stress requires specific regulatory adaptations resulting in a phenotype of allostatically driven chronic stress-sensitization. We propose that these adaptations indicate a physiological cost of adaptation to chronic stress. Model simulations suggest that individuals with high adrenal sensitivity are more vulnerable to chronic stress sensitization and might be more susceptible to the development of neuropsychiatric disorders. These results contribute to the study of sex differences in physiological feedback systems within a quantitative framework.

Banxia-houpu decoction restores glucose intolerance in CUMS rats through improvement of insulin signaling and suppression of NLRP3 inflammasome activation in liver and brain

ETHNOPHARMACOLOGICAL RELEVANCE

Banxia-houpu decoction is a famous formula in traditional Chinese medicine (TCM) with the powerful anti-depressant activity.

AIM OF THE STUDY

This study aimed to investigate the effect of Banxia-houpu decoction on glucose intolerance associated with anhedonia in chronic unpredictable mild stress (CUMS) rats, then to explore its underlying pharmacological mechanisms.

MATERIALS AND METHODS

After 6-week CUMS procedure, male Wistar rats were given Banxia-houpu decoction (3.29 and 6.58g/kg, intragastrically) for 6 weeks. Sucrose solution consumption test was employed to evaluate the anhedonia behavior. Oral glucose tolerance test (OGTT) was used to determine glucose tolerance. Serum levels of corticosterone, corticotropin-releasing factor (CRF), insulin and interleukin-1 beta (IL-1β) were measured by commercial enzyme-linked immunosorbent assay kits, respectively. Furthermore, the key proteins for insulin signaling, as well as nod-like receptor family pyrin domain containing 3 (NLRP3) inflammasome, were analyzed by Western blot in periphery liver and brain regions hypothalamus, hippocampus and prefrontal cortex, respectively.

RESULTS

Banxia-houpu decoction significantly increased sucrose solution consumption and decreased serum corticosterone and CRF levels in CUMS rats, further demonstrating its antidepressant activity. More importantly, Banxia-houpu decoction improved glucose tolerance in OGTT in this animal model. Furthermore, it protected against CUMS-induced insulin signaling impairment in the liver, as well as hypothalamus and prefrontal cortex in rats. Although without significant effect on serum IL-1β levels, Banxia-houpu decoction inhibited NLRP3 inflammasome activation in the liver, hypothalamus, hippocampus and prefrontal cortex of CUMS rats, respectively.

CONCLUSIONS

The present study demonstrates that Banxia-houpu decoction suppresses NLRP3 inflammasome activation and improves insulin signaling impairment in both periphery liver and brain regions in CUMS rats, possibly contributing to its anti-depressive effect with glucose tolerance improvement. These results may provide the evidence that Banxia-houpu decoction is a potential antidepressant with the advantage to reduce the risk of comorbid depression with type 2 diabetes mellitus.

HPA axis in major depression: cortisol, clinical symptomatology and genetic variation predict cognition

The hypothalamic-pituitary-adrenal (HPA) axis has been implicated in the pathophysiology of a variety of mood and cognitive disorders. Neuroendocrine studies have demonstrated HPA axis overactivity in major depression, a relationship of HPA axis activity to cognitive performance and a potential role of HPA axis genetic variation in cognition. The present study investigated the simultaneous roles HPA axis activity, clinical symptomatology and HPA genetic variation play in cognitive performance. Patients with major depression with psychotic major depression (PMD) and with nonpsychotic major depression (NPMD) and healthy controls (HC) were studied. All participants underwent a diagnostic interview and psychiatric ratings, a comprehensive neuropsychological battery, overnight hourly blood sampling for cortisol and genetic assessment. Cognitive performance differed as a function of depression subtype. Across all subjects, cognitive performance was negatively correlated with higher cortisol, and PMD patients had higher cortisol than did NPMDs and HCs. Cortisol, clinical symptoms and variation in genes, NR3C1 (glucocorticoid receptor; GR) and NR3C2 (mineralocorticoid receptor; MR) that encode for GRs and MRs, predicted cognitive performance. Beyond the effects of cortisol, demographics and clinical symptoms, NR3C1 variation predicted attention and working memory, whereas NR3C2 polymorphisms predicted memory performance. These findings parallel the distribution of GR and MR in primate brain and their putative roles in specific cognitive tasks. HPA axis genetic variation and activity were important predictors of cognition across the entire sample of depressed subjects and HR. GR and MR genetic variation predicted unique cognitive functions, beyond the influence of cortisol and clinical symptoms. GR genetic variation was implicated in attention and working memory, whereas MR was implicated in verbal memory.

Comparison of hair thyroid hormones between first-episode and recurrent patients with depression in female Chinese

OBJECTIVE

The aim of this study was to compare hair thyroid hormone (TH) levels among first-episode patients with major depressive disorder (F-MDD), recurrent patients with major depressive disorder (R-MDD) and healthy controls (HC).

METHODS

The Hamilton Depression Scale (HAMD) and Hamilton Anxiety Scale (HAMA) were used to evaluate the clinical symptoms of patients. Electrochemiluminescence immunoassay was used to measure the hair TH levels. We compared the differences in hair TH levels among F-MDD patients, R-MDD patients, and HC.

RESULTS

Before the disease episode, hair T3 levels differed significantly between F-MDD patients and HC. In the disease episode, hair T3 levels differed significantly between F-MDD or R-MDD patients and HC; and hair T4 levels differed significantly between R-MDD patients and HC. Hair T3 levels significantly negative correlated with HAMD scores in F-MDD patients.

CONCLUSIONS

Our findings suggested that disease duration of recurring episodes of depression may influence hair TH levels.

Posttraumatic stress disorder: A metabolic disorder in disguise?

Posttraumatic stress disorder (PTSD) is a heterogeneous psychiatric disorder that affects individuals exposed to trauma and is highly co-morbid with other adverse health outcomes, including cardiovascular disease and obesity. The unique pathophysiological feature of PTSD is the inability to inhibit fear responses, such that individuals suffering from PTSD re-experience traumatic memories and are unable to control psychophysiological responses to trauma-associated stimuli. However, underlying alterations in sympathetic nervous system activity, neuroendocrine systems, and metabolism associated with PTSD are similar to those present in traditional metabolic disorders, such as obesity and diabetes. The current review highlights existing clinical, translational, and preclinical data that support the notion that underneath the primary indication of impaired fear inhibition, PTSD is itself also a metabolic disorder and proposes altered function of inflammatory responses as a common underlying mechanism. The therapeutic implications of treating PTSD as a whole-body condition are significant, as targeting any underlying biological system whose activity is altered in both PTSD and metabolic disorders, (i.e. HPA axis, sympathetic nervous systems, inflammation) may elicit symptomatic relief in individuals suffering from these whole-body adverse outcomes.

Evidence of Polygenic Adaptation in the Systems Genetics of Anthropometric Traits

Many signals of natural selection have been identified in the human genome. However, except for some single-locus mechanisms, most molecular processes generating these adaptation signals are still unknown. We developed an approach that integrates datasets related to genome-wide association studies (GWAS) with information about systems biology and genetic signatures of natural selection to identify evidence of polygenic adaptation. Specifically, we focused on five anthropometric measurements: body mass index (BMI), height, waist-to-hip ratio adjusted for BMI (WHR), and waist circumference adjusted for BMI (WC), and sex differences for WHR and WC. We performed an enrichment analysis for signals of natural selection in protein interaction networks associated with anthropometric traits in European populations. The adaptation signals-enriched gene networks associated highlighted epistatic interactions in the context of polygenic selection for the investigated traits. These polygenic mechanisms indicated intriguing selective mechanisms related to the anthropometric traits: adult locomotory behavior for BMI, infection resistance for height, interplay between lipid transport and immune systems for WHR, and female-specific polygenic adaptation for WHR and WC. In conclusion, we observed evidence of polygenic adaptation in the context of systems genetics of anthropometric traits that indicates polygenic mechanisms related to the natural selection in European populations.

A Systematic, Multi-domain Review of Mobile Smartphone Apps for Evidence-Based Stress Management

CONTEX

Chronic stress presents a growing, pervasive burden in healthcare, and mobile smartphone applications (apps) have the potential to deliver evidence-based stress management strategies. This review identified and evaluated stress management apps across domains of (1) evidence-based content; (2) transparency in app development; and (3) functionality of the app interface.

EVIDENCE ACQUISITION

The iOS App Store was systematically searched. Apps with descriptions indicating that they targeted the intended audience and included evidence-related terminology, at least one evidence-based stress management strategy, and behavior change components were downloaded and evaluated by two independent raters across the three domains of evidence-based content, transparency, and functionality.

EVIDENCE SYNTHESIS

A total of 902 apps were identified based on 21 searches. Of these, 60 met study criteria and were downloaded and evaluated between April and June 2015. Twenty (33%) ultimately did not deliver an evidence-based strategy. Of the delivered strategies, the most common were mindfulness and meditation (73%) and diaphragmatic breathing (25%). On average, apps addressed half of the transparency criteria, and nearly all (85%) were acceptable across usability criteria. A total of 32 apps included both evidence-based content and exhibited no problems with usability or functionality; apps affiliated with a non-profit, research-engaged institution comprised 31% of these.

CONCLUSIONS

This review evaluated 60 iOS apps for stress management across domains of evidence-based content, transparency, and functionality; these apps have the potential to effectively supplement medical care. Findings further indicate that a comprehensive, multi-domain approach can distinguish apps that use evidence-based strategies from those that do not.

Sertraline inhibits increases in body fat and carbohydrate dysregulation in adult female cynomolgus monkeys

Selective serotonin reuptake inhibitor (SSRI) antidepressants are widely prescribed for depression and other disorders. SSRIs have become one of the most commonly used drugs in the United States, particularly by women. Acute effects on body composition and carbohydrate metabolism have been reported, but little is known regarding the effects of chronic SSRI use. We evaluated the effects of chronic administration of a commonly prescribed SSRI, sertraline HCl, on body weight and composition, fat distribution, carbohydrate metabolism, as well as activity, in adult female depressed and nondepressed cynomolgus monkeys (Macaca fascicularis; n=42) using a placebo-controlled, longitudinal, randomized study design. Phenotypes were evaluated prior to and after 18 months of oral sertraline (20mg/kg) or placebo. Over the 18 month treatment period, the placebo group experienced increases in body weight, body fat (visceral and subcutaneous) fasting insulin concentrations, and homeostasis model assessment of insulin resistance scores (HOMA-IR). Sertraline treatment prevented increases in body weight, fat, insulin, and HOMA-IR (all p<0.05), without significantly altering activity levels. Sertraline treatment altered adiponectin in an unusual way - reducing circulating adiponectin in depressed monkeys without affecting fat mass or body weight. Deleterious effects on adiponectin, a potentially insulin-sensitizing and atheroprotective protein, may result in adverse effects on cardiovascular health despite otherwise beneficial effects on body composition and carbohydrate metabolism.

Early-life experiences and the development of adult diseases with a focus on mental illness: The Human Birth Theory

In mammals, early adverse experiences, including mother-pup interactions, shape the response of an individual to chronic stress or to stress-related diseases during adult life. This has led to the elaboration of the theory of the developmental origins of health and disease, in particular adult diseases such as cardiovascular and metabolic disorders. In addition, in humans, as stated by Massimo Fagioli's Human Birth Theory, birth is healthy and equal for all individuals, so that mental illness develop exclusively in the postnatal period because of the quality of the relationship in the first year of life. Thus, this review focuses on the importance of programming during the early developmental period on the manifestation of adult diseases in both animal models and humans. Considering the obvious differences between animals and humans we cannot systematically move from animal models to humans. Consequently, in the first part of this review, we will discuss how animal models can be used to dissect the influence of adverse events occurring during the prenatal and postnatal periods on the developmental trajectories of the offspring, and in the second part, we will discuss the role of postnatal critical periods on the development of mental diseases in humans. Epigenetic mechanisms that cause reversible modifications in gene expression, driving the development of a pathological phenotype in response to a negative early postnatal environment, may lie at the core of this programming, thereby providing potential new therapeutic targets. The concept of the Human Birth Theory leads to a comprehension of the mental illness as a pathology of the human relationship immediately after birth and during the first year of life.

Dopamine-prolactin pathway potentially contributes to the schizophrenia and type 2 diabetes comorbidity

Schizophrenia (SCZ) and type 2 diabetes (T2D) are clinically associated, and common knowledge attributes this association to side effects of antipsychotic treatment. However, even drug-naive patients with SCZ are at increased risk for T2D. Dopamine dysfunction has a central role in SCZ. It is well-known that dopamine constitutively inhibits prolactin (PRL) secretion via the dopamine receptor 2 (DR2D). If dopamine is increased or if dopamine receptors hyperfunction, PRL may be reduced. During the first SCZ episode, low PRL levels are associated with worse symptoms. PRL is essential in human and social bonding, as well as it is implicated in glucose homeostasis. Dopamine dysfunction, beyond contributing to SCZ symptoms, may lead to altered appetite and T2D. To our knowledge, there are no studies of the genetics of the SCZ-T2D comorbidity focusing jointly on the dopamine and PRL pathway in the attempt to capture molecular heterogeneity correlated to possible disease manifestation heterogeneity. In this dopamine-PRL pathway-focused-hypothesis-driven review on the association of SCZ with T2D, we report a specific revision of what it is known about PRL and dopamine in relation to what we theorize is one of the missing links between the two disorders. We suggest that new studies are necessary to establish the genetic role of PRL and dopamine pathway in SCZ-T2D comorbidity.

Abuse in Childhood or Adolescence and Gestational Diabetes: A Retrospective Cohort Study

INTRODUCTION

Early life abuse has been linked to later Type 2 diabetes, but its association with gestational diabetes has not been examined. The aim of this study was to examine the association between childhood and adolescent abuse victimization and risk of gestational diabetes in the Nurses' Health Study II.

METHODS

Participants were asked about experiences of physical and sexual abuse in childhood or adolescence in 2001 and about history of pregnancy complications in 2009. Mothers of singleton live births who provided information on their abuse history comprised the study sample. Modified Poisson regression was used to estimate risk ratios and 95% CIs for gestational diabetes as a function of physical and sexual abuse victimization. Analyses were conducted in 2014-2015.

RESULTS

Of 45,550 women in the analysis, 8% reported severe physical abuse and 11% reported forced sexual activity in childhood or adolescence. Approximately 3% (n=3,181) of pregnancies were complicated by gestational diabetes. In adjusted models, severe physical abuse was associated with a 42% greater gestational diabetes risk (risk ratio=1.42, 95% CI=1.21, 1.66) relative to no physical abuse. Forced sexual activity was associated with a 30% greater risk (95% CI=1.14, 1.49). Women with histories of both physical and sexual abuse were at higher risk than women exposed to a single type of abuse. These associations were not explained by overweight status in early adulthood or prior to pregnancy.

CONCLUSIONS

Childhood and adolescent victimization is associated with increased risk of gestational diabetes in adult women.

Antidepressant-like effect of simvastatin in diabetic rats

Diabetes mellitus is accompanied by hormonal and neurochemical changes that can be associated with anxiety and depression. I investigated the antidepressant effect of simvastatin (SMV) on diabetic rats. Rats were divided into control (CTR) and streptozotocin-induced diabetic (STZ) groups and were orally administered 0, 5, or 10 mg/kg of SMV daily for 14 days, then exposed to the forced swimming test (FST). Our results showed that diabetic rats had higher immobility duration than the CTR rats, and SMV decreased this depressive-like behavior in the diabetic rats. However, clomipramine lowered the immobility time in the CTR and STZ rats. STZ decreased serotonin concentration in the hippocampus, which was reversed by SMV and clomipramine. The dopamine concentration in the hippocampus decreased in the STZ groups compared with the CTR groups. However, SMV and clomipramine had no significant effect on the dopamine levels in either the CTR or STZ groups. Corticosterone levels were increased in the untreated STZ group; SMV and clomipramine significantly decreased corticosterone levels in the STZ groups, but had no effect on the CTR groups. In conclusion, SMV exerts an antidepressant-like effect on diabetic rats that are submitted to the FST. The antidepressant-like effect of SMV in the FST appears to be mediated, at least in part, by the biochemical changes to the blood levels of corticosterone and of serotonin concentration in the hippocampus.

The effect of a preparation of minerals, vitamins and trace elements on the cardiac gene expression pattern in male diabetic rats

Background

Diabetic patients have an increased risk of developing cardiovascular diseases, which are the leading cause of death in developed countries. Although multivitamin products are widely used as dietary supplements, the effects of these products have not been investigated in the diabetic heart yet. Therefore, here we investigated if a preparation of different minerals, vitamins, and trace elements (MVT) affects the cardiac gene expression pattern in experimental diabetes.

Methods

Two-day old male Wistar rats were injected with streptozotocin (i.p. 100 mg/kg) or citrate buffer to induce diabetes. From weeks 4 to 12, rats were fed with a vehicle or a MVT preparation. Fasting blood glucose measurement and oral glucose tolerance test were performed at week 12, and then total RNA was isolated from the myocardium and assayed by rat oligonucleotide microarray for 41012 oligonucleotides.

Results

Significantly elevated fasting blood glucose concentration and impaired glucose tolerance were markedly improved by MVT-treatment in diabetic rats at week 12. Genes with significantly altered expression due to diabetes include functional clusters related to cardiac hypertrophy (e.g. caspase recruitment domain family, member 9; cytochrome P450, family 26, subfamily B, polypeptide; FXYD domain containing ion transport regulator 3), stress response (e.g. metallothionein 1a; metallothionein 2a; interleukin-6 receptor; heme oxygenase (decycling) 1; and glutathione S-transferase, theta 3), and hormones associated with insulin resistance (e.g. resistin; FK506 binding protein 5; galanin/GMAP prepropeptide). Moreover the expression of some other genes with no definite cardiac function was also changed such as e.g. similar to apolipoprotein L2; brain expressed X-linked 1; prostaglandin b2 synthase (brain). MVT-treatment in diabetic rats showed opposite gene expression changes in the cases of 19 genes associated with diabetic cardiomyopathy. In healthy hearts, MVT-treatment resulted in cardiac gene expression changes mostly related to immune response (e.g. complement factor B; complement component 4a; interferon regulatory factor 7; hepcidin).

Conclusions

MVT-treatment improved diagnostic markers of diabetes. This is the first demonstration that MVT-treatment significantly alters cardiac gene expression profile in both control and diabetic rats. Our results and further studies exploring the mechanistic role of individual genes may contribute to the prevention or diagnosis of cardiac complications in diabetes.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-015-0248-6) contains supplementary material, which is available to authorized users.

Ancestral experience as a game changer in stress vulnerability and disease outcomes

Stress is one of the most powerful experiences to influence health and disease. Through epigenetic mechanisms, stress may generate a footprint that propagates to subsequent generations. Programming by prenatal stress or adverse experience in parents, grandparents, or earlier generations may thus be a critical determinant of lifetime health trajectories. Changes in regulation of microRNAs (miRNAs) by stress may enhance the vulnerability to certain pathogenic factors. This review explores the hypothesis that miRNAs represent stress-responsive elements in epigenetic regulation that are potentially heritable. Recent findings suggest that miRNAs are key players linking adverse early environments or ancestral stress with disease risk, thus they represent useful predictive disease biomarkers. Since miRNA signatures of disease are potentially heritable, big data management platforms will be vital to harness multi-generational information and capture succinct yet potent biomarkers capable of directing preventative treatments. This feature would offer a unique window of opportunity to advance personalized medicine.