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Why Publish in the Journal of eScience Librarianship?

Wed, 04/27/2016 - 11:42am

Promotional flyer for the Journal of eScience Librarianship (JeSLIB), an open access, peer-reviewed journal published by the Lamar Soutter Library at UMass Medical School. JeSLIB advances the theory and practice of librarianship with a special focus on services related to data-driven research in the physical, biological, social, and medical sciences, including public health.

Improving Viral Protease Inhibitors to Counter Drug Resistance

Tue, 04/26/2016 - 2:10pm

Drug resistance is a major problem in health care, undermining therapy outcomes and necessitating novel approaches to drug design. Extensive studies on resistance to viral protease inhibitors, particularly those of HIV-1 and hepatitis C virus (HCV) protease, revealed a plethora of information on the structural and molecular mechanisms underlying resistance. These insights led to several strategies to improve viral protease inhibitors to counter resistance, such as exploiting the essential biological function and leveraging evolutionary constraints. Incorporation of these strategies into structure-based drug design can minimize vulnerability to resistance, not only for viral proteases but for other quickly evolving drug targets as well, toward designing inhibitors one step ahead of evolution to counter resistance with more intelligent and rational design.

The Role of Librarians in Data Science: A Call to Action

Tue, 04/26/2016 - 11:21am

Many academic institutions and their libraries have developed research data services, but sometimes institutional objectives, professional organizations, and librarians’ current and future roles aren’t always in sync. In this issue of the Journal of eScience Librarianship, librarians report on moving forward with various services, but frequently face institutional and professional obstacles.

Health Policy 101: A Video for Future Clinicians

Mon, 04/25/2016 - 4:18pm

During my two-week health policy clerkship, my interprofessional group learned a tremendous amount about the current state of health policy. When speaking to our peers, it was clear that many students, both in the GSN and medical school, knew very little about this topic. Our group realized that clinicians are the heart of moving this issue forward, and therefore, educating future clinicians is critical.

When attempting to locate educational tools for future clinicians on health policy, very little was available. This discovery became the reason why I chose to develop an online resource for future clinicians. Due to my previous career in marketing, I determined that a short video, that is easily accessible online, would be a great way to educate current and future UMass Medical students.

The goal of the video is to educate current and future UMass Medical students on the current state of health policy in Massachusetts, and motivate students to become an activate participant in the policy transformation discussion.

The video is available online by clicking here: https://youtu.be/HKVraUGeeFs

For any questions about the video, please contact Stephanie.salvi@umassmed.edu.

Adolescent Sexual Health in Barre, Massachusetts

Mon, 04/25/2016 - 4:18pm

Like many public school systems across the country, cuts to funding have impacted the availability of sexual health education for youth in Barre, Massachusetts. Barre Family Health Center, a federally qualified community health center, in partnership with students from University of Massachusetts Medical School are attempting to fill the gap with Girl Talk!, a curriculum developed to promote empowerment, self-awareness and health to youth. Girl Talk! is a 10 week program for girls ages 10 to 12, focusing on sexual health while also promoting self-esteem, safety & communication through dynamic activities. We evaluated the efficacy of the program using qualitative interviews with participants and their parents. Based on initial data from the inaugural session, several topics have been added to the curriculum including bullying, self-harm, safe social media use, and eating disorders. We have also begun conducting a needs assessment for building a program to include boys, called Guy Talk!. This curriculum will parallel Girl Talk! with particular attention to the needs that boys have surrounding sexual health. To reach more of the community and make sexual health information more available to youth, we have developed a multi-faceted approach by building a partnership with the local high school, parents, and student groups. We feel this comprehensive approach to sexual health promotion in the community, which connects the local health center, high school, and youth is both sustainable and essential for the health of individuals, families, and community.

Family Practice Based Interventions to Reduce Stress in Parents

Mon, 04/25/2016 - 4:18pm

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders typically diagnosed before the age of three that effect the child’s behavior, communication and social skills. Although a pediatric neuropsychologist often confirms a diagnosis of this disorder, the primary care provider is highly involved in the ongoing care of the autistic child. It is well researched that parenting a child with ASD is correlated with high levels of stress, anxiety and depression. While the current interventions for the child with ASD vastly improve the child lifetime outcomes, there are few programs in place beyond “support group” to address the specific mental health needs of the parent caring for a child with ASD. This research asks how a family-practice-based peer support group with rotations of primary care providers, nursing staff, occupational/physical therapists, and mental health counselors compared to standard ASD intervention alone affects the stress experienced by parents of children with autism over a one year period. A literature search of PubMed, The Cochrane Library, Scopus, Eric and PsychINFO yielded six appropriate articles for a literature review. The outcomes of these studies were reviewed, compared and summarized, and it was concluded that although the interventions examined in the literature varied in modality, length and setting, there was sufficient evidence to suggest that the above mentioned intervention would result in decreased stress in parents of children with ASD. Further research is needed to determine how best to determine which modes of intervention are most appropriate for specific stressful triggers.

Excitatory transmission onto AgRP neurons is regulated by cJun NH2-terminal kinase 3 in response to metabolic stress

Sun, 04/24/2016 - 10:16pm

The cJun NH2-terminal kinase (JNK) signaling pathway is implicated in the response to metabolic stress. Indeed, it is established that the ubiquitously expressed JNK1 and JNK2 isoforms regulate energy expenditure and insulin resistance. However, the role of the neuron-specific isoform JNK3 is unclear. Here we demonstrate that JNK3 deficiency causes hyperphagia selectively in high fat diet (HFD)-fed mice. JNK3 deficiency in neurons that express the leptin receptor LEPRb was sufficient to cause HFD-dependent hyperphagia. Studies of sub-groups of leptin-responsive neurons demonstrated that JNK3 deficiency in AgRP neurons, but not POMC neurons, was sufficient to cause the hyperphagic response. These effects of JNK3 deficiency were associated with enhanced excitatory signaling by AgRP neurons in HFD-fed mice. JNK3 therefore provides a mechanism that contributes to homeostatic regulation of energy balance in response to metabolic stress.

Combined Activities of JNK1 and JNK2 in Hepatocytes Protect Against Toxic Liver Injury

Sun, 04/24/2016 - 10:16pm

BACKGROUND and AIMS: c-Jun N-terminal kinase (JNK) 1 and JNK2 are expressed in hepatocytes and have overlapping and distinct functions. JNK proteins are activated via phosphorylation in response to acetaminophen- or carbon tetrachloride (CCl4)-induced liver damage; the level of activation correlates with the degree of injury. SP600125, a JNK inhibitor, has been reported to block acetaminophen-induced liver injury. We investigated the role of JNK in drug-induced liver injury (DILI) in liver tissue from patients and in mice with genetic deletion of JNK in hepatocytes.

METHODS: We studied liver sections from patients with DILI (due to acetaminophen, phenprocoumon, nonsteroidal anti-inflammatory drugs, or autoimmune hepatitis) or patients without acute liver failure (controls) collected from a DILI Biobank in Germany. Levels of total and activated (phosphorylated) JNK were measured by immunohistochemistry and Western blotting. Mice with hepatocyte-specific deletion of Jnk1 (Jnk1(Deltahepa)) or combination of Jnk1 and Jnk2 (Jnk(Deltahepa)), as well as Jnk1-floxed C57BL/6 (control) mice, were given injections of CCl4 (to induce fibrosis) or acetaminophen (to induce toxic liver injury). We performed gene expression microarray and phosphoproteomic analyses to determine mechanisms of JNK activity in hepatocytes.

RESULTS: Liver samples from DILI patients contained more activated JNK, predominantly in nuclei of hepatocytes and in immune cells, than healthy tissue. Administration of acetaminophen to Jnk(Deltahepa) mice produced a greater level of liver injury than that observed in Jnk1(Deltahepa) or control mice, based on levels of serum markers and microscopic and histologic analysis of liver tissues. Administration of CCl4 also induced stronger hepatic injury in Jnk(Deltahepa) mice, based on increased inflammation, cell proliferation, and fibrosis progression, compared with Jnk1(Deltahepa) or control mice. Hepatocytes from Jnk(Deltahepa) mice given acetaminophen had an increased oxidative stress response, leading to decreased activation of adenosine monophosphate-activated protein kinase, total protein adenosine monophosphate-activated protein kinase levels, and pJunD and subsequent necrosis. Administration of SP600125 before or with acetaminophen protected Jnk(Deltahepa) and control mice from liver injury.

CONCLUSIONS: In hepatocytes, JNK1 and JNK2 appear to have combined effects in protecting mice from CCl4- and acetaminophen-induced liver injury. It is important to study the tissue-specific functions of both proteins, rather than just JNK1, in the onset of toxic liver injury. JNK inhibition with SP600125 shows off-target effects.

Fibroblast Growth Factor 21 Mediates Glycemic Regulation by Hepatic JNK

Fri, 04/22/2016 - 3:35pm

The cJun NH2-terminal kinase (JNK)-signaling pathway is implicated in metabolic syndrome, including dysregulated blood glucose concentration and insulin resistance. Fibroblast growth factor 21 (FGF21) is a target of the hepatic JNK-signaling pathway and may contribute to the regulation of glycemia. To test the role of FGF21, we established mice with selective ablation of the Fgf21 gene in hepatocytes. FGF21 deficiency in the liver caused marked loss of FGF21 protein circulating in the blood. Moreover, the protective effects of hepatic JNK deficiency to suppress metabolic syndrome in high-fat diet-fed mice were not observed in mice with hepatocyte-specific FGF21 deficiency, including reduced blood glucose concentration and reduced intolerance to glucose and insulin. Furthermore, we show that JNK contributes to the regulation of hepatic FGF21 expression during fasting/feeding cycles. These data demonstrate that the hepatokine FGF21 is a key mediator of JNK-regulated metabolic syndrome.

Regulation of Adipose Tissue Inflammation and Insulin Resistance by MAPK Phosphatase 5

Fri, 04/22/2016 - 3:34pm

Obesity and metabolic disorders such as insulin resistance and type 2 diabetes have become a major threat to public health globally. The mechanisms that lead to insulin resistance in type 2 diabetes have not been well understood. In this study, we show that mice deficient in MAPK phosphatase 5 (MKP5) develop insulin resistance spontaneously at an early stage of life and glucose intolerance at a later age. Increased macrophage infiltration in white adipose tissue of young MKP5-deficient mice correlates with the development of insulin resistance. Glucose intolerance in MKP5-deficient mice is accompanied by significantly increased visceral adipose weight, reduced AKT activation, enhanced p38 activity, and increased inflammation in visceral adipose tissue when compared with wild-type (WT) mice. Deficiency of MKP5 resulted in increased inflammatory activation in macrophages. These findings thus demonstrate that MKP5 critically controls inflammation in white adipose tissue and the development of metabolic disorders.

Presynaptic c-Jun N-terminal Kinase 2 regulates NMDA receptor-dependent glutamate release

Fri, 04/22/2016 - 3:34pm

Activation of c-Jun N-terminal kinase (JNK) signaling pathway is a critical step for neuronal death occurring in several neurological conditions. JNKs can be activated via receptor tyrosine kinases, cytokine receptors, G-protein coupled receptors and ligand-gated ion channels, including the NMDA glutamate receptors. While JNK has been generally associated with postsynaptic NMDA receptors, its presynaptic role remains largely unexplored. Here, by means of biochemical, morphological and functional approaches, we demonstrate that JNK and its scaffold protein JIP1 are also expressed at the presynaptic level and that the NMDA-evoked glutamate release is controlled by presynaptic JNK-JIP1 interaction. Moreover, using knockout mice for single JNK isoforms, we proved that JNK2 is the essential isoform in mediating this presynaptic event. Overall the present findings unveil a novel JNK2 localization and function, which is likely to play a role in different physiological and pathological conditions.

p38alpha MAPK is required for tooth morphogenesis and enamel secretion

Fri, 04/22/2016 - 3:33pm

An improved understanding of the molecular pathways that drive tooth morphogenesis and enamel secretion is needed to generate teeth from organ cultures for therapeutic implantation or to determine the pathogenesis of primary disorders of dentition (Abdollah, S., Macias-Silva, M., Tsukazaki, T., Hayashi, H., Attisano, L., and Wrana, J. L. (1997) J. Biol. Chem. 272, 27678-27685). Here we present a novel ectodermal dysplasia phenotype associated with conditional deletion of p38alpha MAPK in ectodermal appendages using K14-cre mice (p38alpha(K14) mice). These mice display impaired patterning of dental cusps and a profound defect in the production and biomechanical strength of dental enamel because of defects in ameloblast differentiation and activity. In the absence of p38alpha, expression of amelogenin and beta4-integrin in ameloblasts and p21 in the enamel knot was significantly reduced. Mice lacking the MAP2K MKK6, but not mice lacking MAP2K MKK3, also show the enamel defects, implying that MKK6 functions as an upstream kinase of p38alpha in ectodermal appendages. Lastly, stimulation with BMP2/7 in both explant culture and an ameloblast cell line confirm that p38alpha functions downstream of BMPs in this context. Thus, BMP-induced activation of the p38alpha MAPK pathway is critical for the morphogenesis of tooth cusps and the secretion of dental enamel.

Impaired JNK signaling cooperates with KrasG12D expression to accelerate pancreatic ductal adenocarcinoma

Fri, 04/22/2016 - 3:33pm

The c-Jun N-terminal protein kinase (JNK) and its two direct activators, namely the mitogen-activated protein kinase (MAPK) kinase 4 (MKK4) and MKK7, constitute a signaling node frequently mutated in human pancreatic ductal adenocarcinoma (PDAC). Here we demonstrate the cooperative interaction of endogenous expression of Kras(G12D) with loss-of-function mutations in mkk4 or both, mkk4 and mkk7 genes in the pancreas. More specifically, impaired JNK signaling in a subpopulation of Pdx1-expressing cells dramatically accelerated the appearance of Kras(G12D)-induced acinar-to-ductal metaplasia and pancreatic intraepithelial neoplasias, which rapidly progressed to invasive PDAC within 10 weeks of age. Furthermore, inactivation of mkk4/mkk7 compromised acinar regeneration following acute inflammatory stress by locking damaged exocrine cells in a permanently de-differentiated state. Therefore, we propose that JNK signaling exerts its tumor suppressive function in the pancreas by antagonizing the metaplastic conversion of acinar cells toward a ductal fate capable of responding to oncogenic stimulation.

Mnk2 alternative splicing modulates the p38-MAPK pathway and impacts Ras-induced transformation

Fri, 04/22/2016 - 3:32pm

The kinase Mnk2 is a substrate of the MAPK pathway and phosphorylates the translation initiation factor eIF4E. In humans, MKNK2, the gene encoding for Mnk2, is alternatively spliced yielding two splicing isoforms with differing last exons: Mnk2a, which contains a MAPK-binding domain, and Mnk2b, which lacks it. We found that the Mnk2a isoform is downregulated in breast, lung, and colon tumors and is tumor suppressive. Mnk2a directly interacts with, phosphorylates, activates, and translocates p38alpha-MAPK into the nucleus, leading to activation of its target genes, increasing cell death and suppression of Ras-induced transformation. Alternatively, Mnk2b is pro-oncogenic and does not activate p38-MAPK, while still enhancing eIF4E phosphorylation. We further show that Mnk2a colocalization with p38alpha-MAPK in the nucleus is both required and sufficient for its tumor-suppressive activity. Thus, Mnk2a downregulation by alternative splicing is a tumor suppressor mechanism that is lost in some breast, lung, and colon tumors.

TNF and MAP kinase signalling pathways

Fri, 04/22/2016 - 3:32pm

The binding of tumour necrosis factor alpha (TNFalpha) to cell surface receptors engages multiple signal transduction pathways, including three groups of mitogen-activated protein (MAP) kinases: extracellular-signal-regulated kinases (ERKs); the cJun NH2-terminal kinases (JNKs); and the p38 MAP kinases. These MAP kinase signalling pathways induce a secondary response by increasing the expression of several inflammatory cytokines (including TNFalpha) that contribute to the biological activity of TNFalpha. MAP kinases therefore function both upstream and down-stream of signalling by TNFalpha receptors. Here we review mechanisms that mediate these actions of MAP kinases during the response to TNFalpha.

Analysis of in vitro insulin-resistance models and their physiological relevance to in vivo diet-induced adipose insulin resistance

Fri, 04/22/2016 - 3:32pm

Diet-induced obesity (DIO) predisposes individuals to insulin resistance, and adipose tissue has a major role in the disease. Insulin resistance can be induced in cultured adipocytes by a variety of treatments, but what aspects of the in vivo responses are captured by these models remains unknown. We use global RNA sequencing to investigate changes induced by TNF-alpha, hypoxia, dexamethasone, high insulin, and a combination of TNF-alpha and hypoxia, comparing the results to the changes in white adipose tissue from DIO mice. We found that different in vitro models capture distinct features of DIO adipose insulin resistance, and a combined treatment of TNF-alpha and hypoxia is most able to mimic the in vivo changes. Using genome-wide DNase I hypersensitivity followed by sequencing, we further examined the transcriptional regulation of TNF-alpha-induced insulin resistance, and we found that C/EPBbeta is a potential key regulator of adipose insulin resistance.

Acyl-CoA synthetase 1 is induced by Gram-negative bacteria and lipopolysaccharide and is required for phospholipid turnover in stimulated macrophages

Fri, 04/22/2016 - 3:31pm

The enzyme acyl-CoA synthetase 1 (ACSL1) is induced by peroxisome proliferator-activated receptor alpha (PPARalpha) and PPARgamma in insulin target tissues, such as skeletal muscle and adipose tissue, and plays an important role in beta-oxidation in these tissues. In macrophages, however, ACSL1 mediates inflammatory effects without significant effects on beta-oxidation. Thus, the function of ACSL1 varies in different tissues. We therefore investigated the signals and signal transduction pathways resulting in ACSL1 induction in macrophages as well as the consequences of ACSL1 deficiency for phospholipid turnover in LPS-activated macrophages. LPS, Gram-negative bacteria, IFN-gamma, and TNFalpha all induce ACSL1 expression in macrophages, whereas PPAR agonists do not. LPS-induced ACSL1 expression is dependent on Toll-like receptor 4 (TLR4) and its adaptor protein TRIF (Toll-like receptor adaptor molecule 1) but does not require the MyD88 (myeloid differentiation primary response gene 88) arm of TLR4 signaling; nor does it require STAT1 (signal transducer and activator of transcription 1) for maximal induction. Furthermore, ACSL1 deletion attenuates phospholipid turnover in LPS-stimulated macrophages. Thus, the regulation and biological function of ACSL1 in macrophages differ markedly from that in insulin target tissues. These results suggest that ACSL1 may have an important role in the innate immune response. Further, these findings illustrate an interesting paradigm in which the same enzyme, ACSL1, confers distinct biological effects in different cell types, and these disparate functions are paralleled by differences in the pathways that regulate its expression.

Activation of p38 MAPK in CD4 T cells controls IL-17 production and autoimmune encephalomyelitis

Fri, 04/22/2016 - 3:31pm

Although several transcription factors have been shown to be critical for the induction and maintenance of IL-17 expression by CD4 Th cells, less is known about the role of nontranscriptional mechanisms. Here we show that the p38 MAPK signaling pathway is essential for in vitro and in vivo IL-17 production by regulating IL-17 synthesis in CD4 T cells through the activation of the eukaryotic translation initiation factor 4E/MAPK-interacting kinase (eIF-4E/MNK) pathway. We also show that p38 MAPK activation is required for the development and progression of both chronic and relapsing-remitting forms of experimental allergic encephalomyelitis (EAE), the principal autoimmune model of multiple sclerosis. Furthermore, we show that regulation of p38 MAPK activity specifically in T cells is sufficient to modulate EAE severity. Thus, mechanisms other than the regulation of gene expression also contribute to Th17 cell effector functions and, potentially, to the pathogenesis of other Th17 cell-mediated diseases.

p38 MAPK-mediated regulation of Xbp1s is crucial for glucose homeostasis

Fri, 04/22/2016 - 3:30pm

Here we show that p38 mitogen-activated protein kinase (p38 MAPK) phosphorylates the spliced form of X-box binding protein 1 (Xbp1s) on its Thr48 and Ser61 residues and greatly enhances its nuclear migration in mice, whereas mutation of either residue to alanine substantially reduces its nuclear translocation and activity. We also show that p38 MAPK activity is markedly reduced in the livers of obese mice compared with lean mice. Further, we show that activation of p38 MAPK by expression of constitutively active MAP kinase kinase 6 (MKK6Glu) greatly enhances nuclear translocation of Xbp1s, reduces endoplasmic reticulum stress and establishes euglycemia in severely obese and diabetic mice. Hence, our results define a crucial role for phosphorylation on Thr48 and Ser61 of Xbp1s in the maintenance of glucose homeostasis in obesity, and they suggest that p38 MAPK activation in the livers of obese mice could lead to a new therapeutic approach to the treatment of type 2 diabetes.

The Ino80 complex prevents invasion of euchromatin into silent chromatin

Fri, 04/22/2016 - 2:27pm

Here we show that the Ino80 chromatin remodeling complex (Ino80C) directly prevents euchromatin from invading transcriptionally silent chromatin within intergenic regions and at the border of euchromatin and heterochromatin. Deletion of Ino80C subunits leads to increased H3K79 methylation and noncoding RNA polymerase II (Pol II) transcription centered at the Ino80C-binding sites. The effect of Ino80C is direct, as it blocks H3K79 methylation by Dot1 in vitro. Heterochromatin stimulates the binding of Ino80C in vitro and in vivo. Our data reveal that Ino80C serves as a general silencing complex that restricts transcription to gene units in euchromatin.