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Summary: Long non-coding RNAs (lncRNAs) are emerging as crucial regulators of beta cell function. Here, we show that an lncRNA-transcribed antisense to Pax6, annotated as Pax6os1/PAX6-AS1, was upregulated by high glucose concentrations in human as well as murine beta cell lines and islets. Elevated expression was also observed in islets from mice on a high-fat diet and patients with type 2 diabetes. Silencing Pax6os1/PAX6-AS1 in MIN6 or EndoC-βH1 cells increased several beta cell signature genes’ expression. Pax6os1/PAX6-AS1 was shown to bind to EIF3D, indicating a role in translation of specific mRNAs, as well as histones H3 and H4, suggesting a role in histone modifications. Important interspecies differences were found, with a stronger phenotype in humans. Only female Pax6os1 null mice fed a high-fat diet showed slightly enhanced glucose clearance. In contrast, silencing PAX6-AS1 in human islets enhanced glucose-stimulated insulin secretion and increased calcium dynamics, whereas overexpression of the lncRNA resulted in the opposite phenotype.

Abstract Background The complex aetiology of type 1 diabetes (T1D), characterised by a detrimental cross‐talk between the immune system and insulin‐producing beta cells, has hindered the development of effective disease‐modifying therapies. The discovery that the pharmacological activation of LRH‐1/NR5A2 can reverse hyperglycaemia in mouse models of T1D by attenuating the autoimmune attack coupled to beta cell survival/regeneration prompted us to investigate whether immune tolerisation could be translated to individuals with T1D by LRH‐1/NR5A2 activation and improve islet survival. Methods Peripheral blood mononuclear cells (PBMCs) were isolated from individuals with and without T1D and derived into various immune cells, including macrophages and dendritic cells. Cell subpopulations were then treated or not with BL001, a pharmacological agonist of LRH‐1/NR5A2, and processed for: (1) Cell surface marker profiling, (2) cytokine secretome profiling, (3) autologous T‐cell proliferation, (4) RNAseq and (5) proteomic analysis. BL001‐target gene expression levels were confirmed by quantitative PCR. Mitochondrial function was evaluated through the measurement of oxygen consumption rate using a Seahorse XF analyser. Co‐cultures of PBMCs and iPSCs‐derived islet organoids were performed to assess the impact of BL001 on beta cell viability. Results LRH‐1/NR5A2 activation induced a genetic and immunometabolic reprogramming of T1D immune cells, marked by reduced pro‐inflammatory markers and cytokine secretion, along with enhanced mitohormesis in pro‐inflammatory M1 macrophages and mitochondrial turnover in mature dendritic cells. These changes induced a shift from a pro‐inflammatory to an anti‐inflammatory/tolerogenic state, resulting in the inhibition of CD4+ and CD8+ T‐cell proliferation. BL001 treatment also increased CD4+/CD25+/FoxP3+ regulatory T‐cells and Th2 cells within PBMCs while decreasing CD8+ T‐cell proliferation. Additionally, BL001 alleviated PBMC‐induced apoptosis and maintained insulin expression in human iPSC‐derived islet organoids. Conclusion These findings demonstrate the potential of LRH‐1/NR5A2 activation to modulate immune responses and support beta cell viability in T1D, suggesting a new therapeutic approach. Key Points LRH‐1/NR5A2 activation in inflammatory cells of individuals with type 1 diabetes (T1D) reduces pro‐inflammatory cell surface markers and cytokine release. LRH‐1/NR5A2 promotes a mitohormesis‐induced immuno‐resistant phenotype to pro‐inflammatory macrophages. Mature dendritic cells acquire a tolerogenic phenotype via LRH‐1/NR5A2‐stimulated mitochondria turnover. LRH‐1/NR5A2 agonistic activation expands a CD4+/CD25+/FoxP3+ T‐cell subpopulation. Pharmacological activation of LRH‐1/NR5A2 improves the survival iPSC‐islets‐like organoids co‐cultured with PBMCs from individuals with T1D.

BackgroundIn the United States, racial and ethnic disparities in substance use treatment outcomes are persistent, especially among underrepresented minority (URM) populations. Technology-based interventions (TBIs) for substance use treatment show promise in reducing barriers to evidence-based treatment, yet no studies have described how TBIs may impact racial or ethnic health equity. ObjectiveThis study explored whether TBIs in substance use treatment research promote health equity among people who identify as African American or Black, Hispanic or Latino, and American Indian or Alaska Native through their inclusion in research. We explored whether research that includes the aforementioned groups consciously considers race and/or ethnicity beyond including these populations as participants. MethodsWe conducted a scoping review of 5 electronic databases to identify TBIs in substance use treatment studies published in English between January 2000 and March 2021. Studies were included if ≥50% of participants identified as African American or Black, Hispanic or Latino, or American Indian or Alaska Native when combined. Included studies were evaluated for conscious consideration of race and ethnicity in at least one manuscript section. Finally, we conducted a critical appraisal of each study’s potential to facilitate insights into the impact of a TBI for members of specific URM groups. ResultsOf 6897 titles and abstracts screened and 1158 full-text articles assessed for eligibility, nearly half (532/1158, 45.9%) of the full-text articles were excluded due to the absence of data on race, ethnicity, or not meeting the aforementioned demographic eligibility criteria. Overall, 110 studies met the inclusion criteria. Study designs included 39.1% (43/110) randomized trials, and 35.5% (39/110) feasibility studies. In total, 47.3% (52/110) of studies used computer-based interventions, including electronic screening, brief interventions, and referrals to treatment, whereas 33.6% (37/110) used interactive voice response, ecological momentary assessment or interventions, or SMS text messaging via mobile phones. Studies focused on the following substances: alcohol or drugs (45/110, 40.9%), alcohol alone (26/110, 23.6%), opioids (8/110, 7.3%), cannabis (6/110, 5.5%), cocaine (4/110, 3.6%), and methamphetamines (3/110, 2.7%). Of the studies that consciously considered race or ethnicity (29/110, 26.4%), 6.4% (7/110) explicitly considered race or ethnicity in all manuscript sections. Overall, 28.2% (31/110) of the studies were critically appraised as having a high confidence in the interpretability of the findings for specific URM groups. ConclusionsWhile the prevalence of TBIs in substance use treatment has increased recently, studies that include and consciously consider URM groups are rare, especially for American Indian or Alaska Native and Hispanic or Latino groups. This review highlights the limited research on TBIs in substance use treatment that promotes racial and ethnic health equity and provides context, insights, and direction for researchers working to develop and evaluate digital technology substance use interventions while promoting health equity.

BACKGROUND: Approximately 10% of patients hospitalized with community-acquired pneumonia (CAP) are bacteremic. Bacteremic Streptococcus pneumoniae pneumonia (BSPP) is the number one cause of mortality, representing up to 70% of all CAP deaths. In fact, all CAP guidelines have identified this issue as one of the most important issues when establishing their recommendations.

The adulteration of food products, including honeys and syrups, is of growing concern in global food markets. Detecting adulterated food products can be difficult using traditional analytical methodologies because of complex sample matrices or poor separation of key compounds. NMR is an analytical tool that circumvents some of these issues by providing a snapshot of chemical components in a sample mixture with minimal and unbiased sample preparation. In this upper-year undergraduate and graduate laboratory, students are introduced to NMR as an analytical tool through the analysis of a honey or syrup sample of their choice. Simple sugars in honeys or syrups are quantified using a single point internal standard, while the NMR signals arising from the complex organic mixture of amino acids, proteins, carbohydrates, and oils found in these syrups are compared against a sample data set using principal component analysis. The experiment highlights the benefits and challenges of NMR as an analytical tool, demonstrating the simplicity of sample preparation and single-point calibration, as well as the limitations of instrument sensitivity and signal resolving power.

A multiomic approach shows that long-term exposure to the Acly inhibitor SB-204990 modulates molecular mechanisms associated with aging.

Abstract Cancer-related cognitive impairment (CRCI) is one of the most concerning conditions experienced by patients living with cancer and has a major impact on their quality of life. Available cognitive assessment tools are too time consuming for day-to-day clinical setting assessments. Importantly, although shorter, screening tools such as the Montreal Cognitive Assessment or the Mini-Mental State Evaluation have demonstrated a ceiling effect in persons with cancer, and thus fail to detect subtle cognitive changes expected in patients with CRCI. This study addresses this lack of cognitive screening tools by developing a novel tool, the Fast Cognitive Evaluation (FaCE). A population of 245 patients with 11 types of cancer at different illness and treatment time-points was enrolled for the analysis. FaCE was developed using Rasch Measurement Theory, a model that establishes the conditions for a measurement tool to be considered a rating scale. FaCE shows excellent psychometric properties. The population size was large enough to test the set of items (item-reliability-index=0.96). Person-reliability (0.65) and person-separation (1.37) indexes indicate excellent internal consistency. FaCE’s scale is accurate (reliable) with high discriminant ability between cognitive levels. Within the average testing time of five minutes, FaCE assesses the main cognitive domains affected in CRCI. FaCE is a rapid, reliable, and sensitive tool for detecting even minimal cognitive changes over time. This can contribute to early and appropriate interventions for better quality of life in patients with CRCI. In addition, FaCE could be used as a measurement tool in research exploring cognitive disorders in cancer survivors.

Summary: XLF/Cernunnos is a component of the ligation complex used in classical non-homologous end-joining (cNHEJ), a major DNA double-strand break (DSB) repair pathway. We report neurodevelopmental delays and significant behavioral alterations associated with microcephaly in Xlf−/− mice. This phenotype, reminiscent of clinical and neuropathologic features in humans deficient in cNHEJ, is associated with a low level of apoptosis of neural cells and premature neurogenesis, which consists of an early shift of neural progenitors from proliferative to neurogenic divisions during brain development. We show that premature neurogenesis is related to an increase in chromatid breaks affecting mitotic spindle orientation, highlighting a direct link between asymmetric chromosome segregation and asymmetric neurogenic divisions. This study reveals thus that XLF is required for maintaining symmetric proliferative divisions of neural progenitors during brain development and shows that premature neurogenesis may play a major role in neurodevelopmental pathologies caused by NHEJ deficiency and/or genotoxic stress.

Type 1 diabetes mellitus (T1DM) is an autoimmune disorder specifically targeting pancreatic islet beta cells. Despite many efforts focused on identifying new therapies able to counteract this autoimmune attack and/or stimulate beta cells regeneration, TD1M remains without effective clinical treatments providing no clear advantages over the conventional treatment with insulin. We previously postulated that both the inflammatory and immune responses and beta cell survival/regeneration must be simultaneously targeted to blunt the progression of disease. Umbilical cord-derived mesenchymal stromal cells (UC-MSC) exhibit anti-inflammatory, trophic, immunomodulatory and regenerative properties and have shown some beneficial yet controversial effects in clinical trials for T1DM. In order to clarify conflicting results, we herein dissected the cellular and molecular events derived from UC-MSC intraperitoneal administration (i.p.) in the RIP-B7.1 mouse model of experimental autoimmune diabetes. Intraperitoneal (i.p.) transplantation of heterologous mouse UC-MSC delayed the onset of diabetes in RIP-B7.1 mice. Importantly, UC-MSC i. p. transplantation led to a strong peritoneal recruitment of myeloid-derived suppressor cells (MDSC) followed by multiple T-, B- and myeloid cells immunosuppressive responses in peritoneal fluid cells, spleen, pancreatic lymph nodes and the pancreas, which displayed significantly reduced insulitis and pancreatic infiltration of T and B Cells and pro-inflammatory macrophages. Altogether, these results suggest that UC-MSC i. p. transplantation can block or delay the development of hyperglycemia through suppression of inflammation and the immune attack.

Extracellular vesicles (EVs), especially exosomes (50 to 150 nm), have been shown to play important roles in a wide range of physiological and pathological processes, including metabolic diseases such as Diabetes Mellitus (DM). In the last decade, several studies have demonstrated how EVs are involved in cell-to-cell communication. EVs are enriched in proteins, mRNAs and non-coding RNAs (miRNAs, long non-coding RNAs and circRNAS, among others) which are transferred to recipient cells and may have a profound impact in either their survival or functionality. Several studies have pointed out the contribution of exosomal miRNAs, such as miR-l42-3p and miR-26, in the development of Type 1 and Type 2 DM (T1DM and T2DM), respectively. In addition, some miRNA families such as miR-let7 and miR-29 found in exosomes have been associated with both types of diabetes, suggesting that they share common etiological features. The knowledge about the role of exosomal long non-coding RNAs in this group of diseases is more immature, but the exosomal lncRNA MALAT1 has been found to be elevated in the plasma of individuals with T2DM, while more than 169 lncRNAs were reported to be differentially expressed between healthy donors and people with T1DM. Here, we review the current knowledge about exosomal non-coding RNAs in DM and discuss their potential as novel biomarkers and possible therapeutic targets.

Summary: LRH-1/NR5A2 is implicated in islet morphogenesis postnatally, and its activation using the agonist BL001 protects islets against apoptosis, reverting hyperglycemia in mouse models of Type 1 Diabetes Mellitus. Islet transcriptome profiling revealed that the expression of PTGS2/COX2 is increased by BL001. Herein, we sought to define the role of LRH-1 in postnatal islet morphogenesis and chart the BL001 mode of action conferring beta cell protection. LRH-1 ablation within developing beta cells impeded beta cell proliferation, correlating with mouse growth retardation, weight loss, and hypoglycemia leading to lethality. LRH-1 deletion in adult beta cells abolished the BL001 antidiabetic action, correlating with beta cell destruction and blunted Ptgs2 induction. Islet PTGS2 inactivation led to reduced PGE2 levels and loss of BL001 protection against cytokines as evidenced by increased cytochrome c release and cleaved-PARP. The PTGER1 antagonist—ONO-8130—negated BL001-mediated islet survival. Our results define the LRH-1/PTGS2/PGE2/PTGER1 signaling axis as a key pathway mediating BL001 survival properties.

BackgroundTechnology-based interventions (TBIs; ie, web-based and mobile interventions) have the potential to promote health equity in substance use treatment (SUTx) for underrepresented groups (people who identify as African American/Black, Hispanic/Latinx, and American Indian/Alaskan Native) by removing barriers and increasing access to culturally relevant effective treatments. However, technologies (emergent and more long-standing) may have unintended consequences that could perpetuate health care disparities among people who identify as a member of one of the underrepresented groups. Health care research, and SUTx research specifically, is infrequently conducted with people who identify with these groups as the main focus. Therefore, an improved understanding of the literature at the intersection of SUTx, TBIs, and underrepresented groups is warranted to avoid exacerbating inequities and to promote health equity. ObjectiveThis study aims to explore peer-reviewed literature (January 2000-March 2021) that includes people who identify as a member of one of the underrepresented groups in SUTx research using TBIs. We further seek to explore whether this subset of research is race/ethnicity conscious (does the research consider members of underrepresented groups beyond their inclusion as study participants in the introduction, methods, results, or discussion). MethodsFive electronic databases (MEDLINE, Scopus, Cochrane Library, CINAHL, and PsycInfo) were searched to identify SUTx research using TBIs, and studies were screened for eligibility at the title/abstract and full-text levels. Studies were included if their sample comprised of people who identify as a member of one of the underrepresented groups at 50% or more when combined. ResultsTitle/abstract and full-text reviews were completed in 2021. These efforts netted a sample of 185 studies that appear to meet inclusionary criteria. Due to the uniqueness of tobacco relative to other substances in the SUTx space, as well as the large number of studies netted, we plan to separately publish a scoping review on tobacco-focused studies that meet all other criteria. Filtering for tobacco-focused studies (n=31) netted a final full-text sample for a main scoping review of 154 studies. The tobacco-focused scoping review manuscript is expected to be submitted for peer review in Spring 2022. The main scoping review data extraction and data validation to confirm the accuracy and consistency of data extraction across records was completed in March 2022. We expect to publish the main scoping review findings by the end of 2022. ConclusionsResearch is needed to increase our understanding of the range and nature of TBIs being used in SUTx research studies with members of underrepresented groups. The planned scoping review will highlight research at this intersection to promote health equity. International Registered Report Identifier (IRRID)DERR1-10.2196/34508

Background and Aims: The synthetic atypical cannabinoid Abn-CBD, a cannabidiol (CBD) derivative, has been recently shown to modulate the immune system in different organs, but its impact in obesity-related meta-inflammation remains unstudied. We investigated the effects of Abn-CBD on metabolic and inflammatory parameters utilizing a diet-induced obese (DIO) mouse model of prediabetes and non-alcoholic fatty liver disease (NAFLD).Materials and Methods: Ten-week-old C57Bl/6J mice were fed a high-fat diet for 15 weeks, following a 2-week treatment of daily intraperitoneal injections with Abn-CBD or vehicle. At week 15 mice were obese, prediabetic and developed NAFLD. Body weight and glucose homeostasis were monitored. Mice were euthanized and blood, liver, adipose tissue and pancreas were collected and processed for metabolic and inflammatory analysis.Results: Body weight and triglycerides profiles in blood and liver were comparable between vehicle- and Abn-CBD-treated DIO mice. However, treatment with Abn-CBD reduced hyperinsulinemia and markers of systemic low-grade inflammation in plasma and fat, also promoting white adipose tissue browning. Pancreatic islets from Abn-CBD-treated mice showed lower apoptosis, inflammation and oxidative stress than vehicle-treated DIO mice, and beta cell proliferation was induced. Furthermore, Abn-CBD lowered hepatic fibrosis, inflammation and macrophage infiltration in the liver when compared to vehicle-treated DIO mice. Importantly, the balance between hepatocyte proliferation and apoptosis was improved in Abn-CBD-treated compared to vehicle-treated DIO mice.Conclusions: These results suggest that Abn-CBD exerts beneficial immunomodulatory actions in the liver, pancreas and adipose tissue of DIO prediabetic mice with NAFLD, thus protecting tissues. Therefore, Abn-CBD and related compounds could represent novel pharmacological strategies for managing obesity-related metabolic disorders.

Mesenchymal stem cells (MSCs) are among the most frequently used cell type for regenerative medicine. A large number of studies have shown the beneficial effects of MSC-based therapies to treat different pathologies, including neurological disorders, cardiac ischemia, diabetes, and bone and cartilage diseases. However, the therapeutic potential of MSCs in cancer is still controversial. While some studies indicate that MSCs may contribute to cancer pathogenesis, emerging data reported the suppressive effects of MSCs on cancer cells. Because of this reality, a sustained effort to understand when MSCs promote or suppress tumor development is needed before planning a MSC-based therapy for cancer. Herein, we provide an overview on the therapeutic application of MSCs for regenerative medicine and the processes that orchestrates tissue repair, with a special emphasis placed on cancer, including central nervous system tumors. Furthermore, we will discuss the current evidence regarding the double-edged sword of MSCs in oncological treatment and the latest advances in MSC-based anti-cancer agent delivery systems.

Summary: Deciphering the mechanisms that regulate the quiescence of adult neural stem cells (NSCs) is crucial for the development of therapeutic strategies based on the stimulation of their endogenous regenerative potential in the damaged brain. We show that LeXbright cells sorted from the adult mouse subventricular zone exhibit all the characteristic features of quiescent NSCs. Indeed, they constitute a subpopulation of slowly dividing cells that is able to enter the cell cycle to regenerate the irradiated niche. Comparative transcriptomic analyses showed that they express hallmarks of NSCs but display a distinct molecular signature from activated NSCs (LeX+EGFR+ cells). Particularly, numerous membrane receptors are expressed on quiescent NSCs. We further revealed a different expression pattern of Syndecan-1 between quiescent and activated NSCs and demonstrated its role in the proliferation of activated NSCs. Our data highlight the central role of the stem cell microenvironment in the regulation of quiescence in adult neurogenic niches. : In this article, Boussin, Mouthon, and colleagues provide transcriptomic profiles of quiescent and activated neural stem cells. They report on the use of Syndecan-1 as a marker to purify long-term proliferating stem cells. Keywords: neural stem cells, cell sorting, microarray, quiescence, syndecan-1, irradiation, adult neurogenic niches, neurogenesis

Type 1 diabetes mellitus (T1DM) is characterized by beta cell loss because of an autoimmune attack. Here the authors show that an agonist for LRH-1/NR5A2, a nuclear receptor known to be protective against beta cell apoptosis, inhibits immune-mediated inflammation and hyperglycemia in T1DM mouse models.

Abstract Background Rates of cesarean delivery are continuously increasing in industrialized countries, with repeated cesarean accounting for about a third of all cesareans. Women who have undergone a first cesarean are facing a difficult choice for their next pregnancy, i.e.: (1) to plan for a second cesarean delivery, associated with higher risk of maternal complications than vaginal delivery; or (b) to have a trial of labor (TOL) with the aim to achieve a vaginal birth after cesarean (VBAC) and to accept a significant, but rare, risk of uterine rupture and its related maternal and neonatal complications. The objective of this trial is to assess whether a multifaceted intervention would reduce the rate of major perinatal morbidity among women with one prior cesarean. Methods/design The study is a stratified, non-blinded, cluster-randomized, parallel-group trial of a multifaceted intervention. Hospitals in Quebec are the units of randomization and women are the units of analysis. As depicted in Figure 1, the study includes a 1-year pre-intervention period (baseline), a 5-month implementation period, and a 2-year intervention period. At the end of the baseline period, 20 hospitals will be allocated to the intervention group and 20 to the control group, using a randomization stratified by level of care. Medical records will be used to collect data before and during the intervention period. Primary outcome is the rate of a composite of major perinatal morbidities measured during the intervention period. Secondary outcomes include major and minor maternal morbidity; minor perinatal morbidity; and TOL and VBAC rate. The effect of the intervention will be assessed using the multivariable generalized-estimating-equations extension of logistic regression. The evaluation will include subgroup analyses for preterm and term birth, and a cost-effectiveness analysis. Discussion The intervention is designed to facilitate: (1) women’s decision-making process, using a decision analysis tool (DAT), (2) an estimate of uterine rupture risk during TOL using ultrasound evaluation of low-uterine segment thickness, (3) an estimate of chance of TOL success, using a validated prediction tool, and (4) the implementation of best practices for intrapartum management. Trial registration Current Controlled Trials, ID: ISRCTN15346559 . Registered on 20 August 2015.

Abstract LH-21 is a triazol derivative that has been described as a low-permeant neutral CB1 antagonist, though its pharmacology is still unclear. It has been associated with anti-obesity actions in obese rats. However, its role in preventing type 2 diabetes (T2D) onset have not been studied yet. Given CB1 receptors remain as potential pharmacological targets to fight against obesity and T2D, we wanted to explore the metabolic impact of this compound in an animal model of obesity and pre-diabetes as well as the lack of relevant actions in related central processes such as anxiety. C57BL/6J mice were rendered obese and pre-diabetic by feeding a high-fat diet for 15 weeks and then treated with LH-21 or vehicle for two weeks. Food intake, body weight and glucose handling were assessed, together with other relevant parameters. Behavioural performance was evaluated by the open field test and the elevated plus maze. LH-21 did not affect food intake nor body weight but it improved glucose handling, displaying tissue-specific beneficial actions. Unexpectedly, LH-21 induced anxiolysis and reverted obesity-induced anxiety, apparently through GPR55 receptor. These results suggest that LH-21 can be a new candidate to fight against diabetes onset. Indeed, this compound shows potential in counteracting obesity-related anxiety.

Type 1 diabetes mellitus (T1DM) is defined as an autoimmune disease that targets the selective destruction of islet insulin-producing beta cells by infiltrating immune cells (insulitis). As a result, the organism is no longer able to produce insulin and develops hyperglycaemia and, if untreated, death. Despite advances in medical device technology and insulin analogues as well as strives in generating in vitro insulin-producing cells, there is still no robust therapy to substitute and protect beta cells that are lost in T1DM. Clinical trials aimed at blocking the immune-mediated beta cell destruction have had moderate success leaving a gap in our understanding of disease aetiology. Such breach in knowledge may stem from the oversight that inhibiting the immune attack likely impairs beta cell regeneration and emphasizes a fundamental paradigm in the approach to treat the disease: A non-mutually exclusive strategy in which the uncontrolled self-directed inflammatory immune response (and not the global immune system) as well as beta cell regeneration are exquisitely fine tuned in order to successfully regain immunological tolerance and restoration of a functional beta cell mass. As such, defining factors that can guide a pro-inflammatory immune cell destructive environment towards an anti-inflammatory environment facilitating beta cell survival and stimulate regeneration would define an unprecedented class of immune-regenerative therapeutic agents for T1DM. In our recent study we identify the liver receptor homolog 1 (LRH-1, also known as NR5A2) as a ‘druggable’ target that fulfills these criteria restoring glycemic control in various mouse models of T1DM as well as improving human islet survival and function both in vitro and in vivo (Nat Comms, 9:1488).

Identifying the mechanisms controlling quiescence and activation of neural stem cells (NSCs) is crucial for understanding brain repair. Here, we demonstrate that Hedgehog (Hh) signaling actively regulates different pools of quiescent and proliferative NSCs in the adult ventricular-subventricular zone (V-SVZ), one of the main brain neurogenic niches. Specific deletion of the Hh receptor Patched in NSCs during adulthood upregulated Hh signaling in quiescent NSCs, progressively leading to a large accumulation of these cells in the V-SVZ. The pool of non-neurogenic astrocytes was not modified, whereas the activated NSC pool increased after a short period, before progressively becoming exhausted. We also showed that Sonic Hedgehog regulates proliferation of activated NSCs in vivo and shortens both their G1 and S-G2/M phases in culture. These data demonstrate that Hh orchestrates the balance between quiescent and activated NSCs, with important implications for understanding adult neurogenesis under normal homeostatic conditions or during injury.

Background : Low positive affect is closely related to common pathological responses to childhood adversity, including posttraumatic stress disorder (PTSD) and depression, but little is known about how the characteristics of early adversity experiences might be related to positive affect in adulthood. Objective : This study aimed to explore whether low positive affect is related to specific childhood adversities, including abuse, neglect, caretaker dysfunction, and low childhood social support. Method : Using structured interviews and self-report measure data collected from 173 adult psychiatric inpatients, this study examined the relationship between positive affect and symptoms of psychopathology, as well as how the number of types of abuse experienced, severity of adversity types (physical abuse and sexual abuse), childhood environment (childhood social support, neglect, and caretaker dysfunction), and number of non-abuse traumas related to positive affect. Results: Positive affect was significantly negatively related to several symptoms of psychopathology, including depression, dissociation, self-destructive behavior, PTSD, and global psychopathology. Individuals who experienced both physical and sexual abuse reported significantly less positive affect than those with only physical or no abuse experiences. Lower positive affect was predicted by lower childhood social support and greater severity of sexual abuse, with both factors accounting for unique variance in positive affect. Conclusion : These results suggest that individuals who experience multiple types of early adversity, more severe sexual abuse experiences, and less social support are at risk of psychological difficulties. Given the relatively strong association between positive affect and childhood social support, interventions to foster social support may be a means of increasing positive affect among individuals exposed to childhood adversity.

Elevated plasma concentration of the pro-atherogenic oxidized low density lipoprotein cholesterol (LDL) triggers adverse effects in pancreatic beta-cells and is associated with type 2 diabetes. Here, we investigated whether the endoplasmic reticulum (ER) stress is a key player coupling oxidative stress to beta-cell dysfunction and death elicited by human oxidized LDL. We found that human oxidized LDL activates ER stress as evidenced by the activation of the inositol requiring 1α, and the elevated expression of both DDIT3 (also called CHOP) and DNAJC3 (also called P58IPK) ER stress markers in isolated human islets and the mouse insulin secreting MIN6 cells. Silencing of Chop and inhibition of ER stress markers by the chemical chaperone phenyl butyric acid (PBA) prevented cell death caused by oxidized LDL. Finally, we found that oxidative stress accounts for activation of ER stress markers induced by oxidized LDL. Induction of Chop/CHOP and p58IPK/P58IPK by oxidized LDL was mimicked by hydrogen peroxide and was blocked by co-treatment with the N-acetylcystein antioxidant. As a conclusion, the harmful effects of oxidized LDL in beta-cells requires ER stress activation in a manner that involves oxidative stress. This mechanism may account for impaired beta-cell function in diabetes and can be reversed by antioxidant treatment.