SnapShot: Neuronal Regulation of Aging.

Aging is characterized by loss of homeostasis across multiple tissues. The nervous system governs whole-body homeostasis by communicating external and internal signals to peripheral tissues. Here, we highlight neuronal mechanisms and downstream outputs that regulate aging and longevity. Targeting these neuronal pathways may be a novel strategy to promote healthy aging. To view this SnapShot, open or download the PDF.

Neuronal CRTC-1 governs systemic mitochondrial metabolism and lifespan via a catecholamine signal.

Low energy states delay aging in multiple species, yet mechanisms coordinating energetics and longevity across tissues remain poorly defined. The conserved energy sensor AMP-activated protein kinase (AMPK) and its corresponding phosphatase calcineurin modulate longevity via the CREB regulated transcriptional coactivator (CRTC)-1 in C. elegans. We show that CRTC-1 specifically uncouples AMPK/calcineurin-mediated effects on lifespan from pleiotropic side effects by reprogramming mitochondrial and metabolic function. This pro-longevity metabolic state is regulated cell nonautonomously by CRTC-1 in the nervous system. Neuronal CRTC-1/CREB regulates peripheral metabolism antagonistically with the functional PPARα ortholog, NHR-49, drives mitochondrial fragmentation in distal tissues, and suppresses the effects of AMPK on systemic mitochondrial metabolism and longevity via a cell-nonautonomous catecholamine signal. These results demonstrate that while both local and distal mechanisms combine to modulate aging, distal regulation overrides local contribution. Targeting central perception of energetic state is therefore a potential strategy to promote healthy aging.

Splicing factor 1 modulates dietary restriction and TORC1 pathway longevity in C. elegans.

Ageing is driven by a loss of transcriptional and protein homeostasis and is the key risk factor for multiple chronic diseases. Interventions that attenuate or reverse systemic dysfunction associated with age therefore have the potential to reduce overall disease risk in the elderly. Precursor mRNA (pre-mRNA) splicing is a fundamental link between gene expression and the proteome, and deregulation of the splicing machinery is linked to several age-related chronic illnesses. However, the role of splicing homeostasis in healthy ageing remains unclear. Here we demonstrate that pre-mRNA splicing homeostasis is a biomarker and predictor of life expectancy in Caenorhabditis elegans. Using transcriptomics and in-depth splicing analysis in young and old animals fed ad libitum or subjected to dietary restriction, we find defects in global pre-mRNA splicing with age that are reduced by dietary restriction via splicing factor 1 (SFA-1; the C. elegans homologue of SF1, also known as branchpoint binding protein, BBP). We show that SFA-1 is specifically required for lifespan extension by dietary restriction and by modulation of the TORC1 pathway components AMPK, RAGA-1 and RSKS-1/S6 kinase. We also demonstrate that overexpression of SFA-1 is sufficient to extend lifespan. Together, these data demonstrate a role for RNA splicing homeostasis in dietary restriction longevity and suggest that modulation of specific spliceosome components may prolong healthy ageing.

Corrigendum: Splicing factor 1 modulates dietary restriction and TORC1 pathway longevity in C. elegans.

This corrects the article DOI: 10.1038/nature20789.

Impact of Checklist Use on Wellness and Post-Elective Surgery Appointments in a Veterinary Teaching Hospital.

Cognitive functioning is often compromised with increasing levels of stress and fatigue, both of which are often experienced by veterinarians. Many high-stress fields have implemented checklists to reduce human error. The use of these checklists has been shown to improve the quality of medical care, including adherence to evidence-based best practices and improvement of patient safety. Although it has been recognized that veterinary medicine would likely demonstrate similar benefits, there have been no published studies to date evaluating the use of checklists for improving quality of care in veterinary medicine. The purpose of the current study was to evaluate the impact of checklists during wellness and post-elective surgery appointments conducted by fourth-year veterinary students within their Community Practice rotation at a US veterinary teaching hospital. Students were randomly assigned to one of two groups: those who were specifically asked to use the provided checklists during appointments, and those who were not asked to use the checklists but had them available. Two individuals blinded to the study reviewed the tapes of all appointments in each study group to determine the amount and type of medical information offered by veterinary students. Students who were specifically asked to use the checklists provided significantly more information to owners, with the exception of keeping the incision clean. Results indicate the use of checklists helps students provide more complete information to their clients, thereby potentially enhancing animal care.

Fragment-Based Discovery of a Series of Allosteric-Binding Site Modulators of ß-Glucocerebrosidase.

ß-Glucocerebrosidase (GBA/GCase) mutations leading to misfolded protein cause Gaucher's disease and are a major genetic risk factor for Parkinson's disease and dementia with Lewy bodies. The identification of small molecule pharmacological chaperones that can stabilize the misfolded protein and increase delivery of degradation-prone mutant GCase to the lysosome is a strategy under active investigation. Here, we describe the first use of fragment-based drug discovery (FBDD) to identify pharmacological chaperones of GCase. The fragment hits were identified by using X-ray crystallography and biophysical techniques. This work led to the discovery of a series of compounds that bind GCase with nM potency and positively modulate GCase activity in cells.

Living in dressings and bandages: findings from workshops with people with Epidermolysis bullosa.

Epidermolysis bullosa (EB) is an inherited disorder causing extensive, painful skin blistering and wounds. Currently, there is no cure and the focus of care is on the clinical management of the skin and other affected body systems, together with supportive care to individuals and families. The wound care for Epidermolysis bullosa (WEB) project is a collaboration with adults with EB, carers, clinical nurse specialists, a designer and manufacturers to develop novel products for EB wound care. This article reports the findings from workshops with adults with EB, their carers and clinical nurse specialists, together with observations of dressing changes. A cluster of significant limitations were revealed in the performance of wound care products, designed to cover a single wound, when they are used to cover extensive and whole body wounds. A working hypothesis for EB wound care was developed from the findings, together with design concepts and new products for EB wound care. In addition, a model of user engagement in medical device development and evaluation has been tested.

Effects of infiltration of the incision site with bupivacaine on postoperative pain and incisional healing in dogs undergoing ovariohysterectomy.

OBJECTIVE: To determine the effects of infiltration of the incision site with bupivacaine hydrochloride as part of a multimodal analgesia protocol (incisional block) on postoperative analgesia and incisional healing. DESIGN: Randomized controlled clinical trial. ANIMALS: 92 shelter-owned female dogs undergoing routine ovariohysterectomy. PROCEDURES: As part of a multimodal analgesic protocol for ovariohysterectomy, dogs received 1 of the following treatments at the incision site: no injection (26 dogs), preincisional infiltration with saline (0.9% NaCl) solution (12 dogs) or bupivacaine (21 dogs), or postincisional infiltration with bupivacaine (33 dogs). Postoperative pain was assessed with the Glasgow pain scale and response to mechanical stimulation with von Frey filaments. Incisions were monitored for signs of inflammation (edema, erythema, and discharge) and complications in wound healing. RESULTS: There was no difference in pain scores or response to mechanical stimulation over time among treatments. There were no significant differences in incisional edema or discharge among treatments. There was significantly more erythema in dogs that received preincisional infiltration with saline solution at 4 hours after surgery and less erythema in dogs that received postincisional infiltration with bupivacaine at 24 hours after surgery, compared with other treatments. The number of complications for dogs that had preincisional infiltration of bupivacaine was higher than for dogs that had other treatments; complications included excessive inflammation, splenic laceration, and herniation. CONCLUSIONS AND CLINICAL RELEVANCE: No additional analgesic benefit was found in dogs that underwent local bupivacaine infiltration as part of a multimodal analgesic protocol for ovariohysterectomy.

Neuronal TORC1 modulates longevity via AMPK and cell nonautonomous regulation of mitochondrial dynamics in C. elegans.

Target of rapamycin complex 1 (TORC1) and AMP-activated protein kinase (AMPK) antagonistically modulate metabolism and aging. However, how they coordinate to determine longevity and if they act via separable mechanisms is unclear. Here, we show that neuronal AMPK is essential for lifespan extension from TORC1 inhibition, and that TORC1 suppression increases lifespan cell non autonomously via distinct mechanisms from global AMPK activation. Lifespan extension by null mutations in genes encoding raga-1 (RagA) or rsks-1 (S6K) is fully suppressed by neuronal-specific rescues. Loss of RAGA-1 increases lifespan via maintaining mitochondrial fusion. Neuronal RAGA-1 abrogation of raga-1 mutant longevity requires UNC-64/syntaxin, and promotes mitochondrial fission cell nonautonomously. Finally, deleting the mitochondrial fission factor DRP-1 renders the animal refractory to the pro-aging effects of neuronal RAGA-1. Our results highlight a new role for neuronal TORC1 in cell nonautonomous regulation of longevity, and suggest TORC1 in the central nervous system might be targeted to promote healthy aging.

Issues and challenges of involving users in medical device development.

BACKGROUND: User engagement has become a central tenet of health-care policy. This paper reports on a case study in progress that highlights user engagement in the research process in relation to medical device development. OBJECTIVES: To work with a specific group of medical device users to uncover unmet needs, translating these into design concepts, novel technologies and products. To validate a knowledge transfer model that may be replicated for a range of medical device applications and user groups. METHODS: In depth qualitative case study to elicit and analyse user needs. The focus is on identifying design concepts for medical device applications from unmet needs, and validating these in an iterative feedback loop to the users. RESULTS: The case study has highlighted three interrelated challenges: ensuring unmet needs drive new design concepts and technology development; managing user expectations and managing the research process. CONCLUSION: Despite the challenges, active participation of users is crucial to developing usable and clinically effective devices.

A model of user engagement in medical device development.

PURPOSE: The purpose of this paper is to address three topical themes: user involvement in health services research; determining the value of new medical technologies in patient care pathways, furthering knowledge related to quality in health and social care; and knowledge exchange between manufacturers, health service supply chain networks and device users. The model is being validated in a case study in progress. The latter is a "proving ground" study for a translational research company. Medical devices play a pivotal role in the management of chronic diseases, across all care settings. Failure to engage users in device development inevitably affects the quality of clinical outcomes. A model of user engagement is presented, turning unmet needs for medical devices into viable commercial propositions. DESIGN/METHODOLOGY/APPROACH: A case study investigating the perceptions of individuals with Epidermolysis Bullosa (EB), their lay and professional carers into unmet needs. EB is an inherited condition affecting the skin and mucosal linings that leads to blistering and wounds. FINDINGS: Qualitative data are being collected to generate understanding of unmet needs and wound care products. These needs are being translated into new design concepts and prototypes. Prototypes will be evaluated in an n = 1 experimental design, generating quantitative outcomes data. ORIGINALITY/VALUE: There are generalisations from the case study, and the model outlined. New products for managing EB wounds can logically benefit other groups. The model is transferable to other clinical problems, which can benefit from research and technological advances that are integral to clinical needs and care.

Rates of intraoperative complications and conversion to laparotomy during laparoscopic ovariectomy performed by veterinary students: 161 cases (2010-2014).

OBJECTIVE To assess rates of intraoperative complications and conversion to laparotomy associated with supervised veterinary students performing laparoscopic ovariectomy in dogs. DESIGN Retrospective case series. ANIMALS 161 female shelter dogs for which elective laparoscopic ovariectomy had been performed by supervised senior (fourth-year) veterinary students from 2010 through 2014. PROCEDURES Medical records of all dogs were reviewed and data collected regarding duration of surgery, surgical complications and other characteristics, and whether conversion to laparotomy was required. RESULTS Laparoscopic ovariectomy was performed with a 2-cannula technique and a 10-mm vessel-sealing device for hemostasis in all dogs. A Veress needle was used for initial insufflation in 144 (89.4%) dogs; method of insufflation was not reported for the remaining 17 (10.6%) dogs. Mean ± SD duration of surgery was 114.90 ± 33.40 minutes. Surgical complications, all classified as minor blood loss, occurred in 24 (14.9%) dogs. These included splenic puncture during insertion of the Veress needle (n = 20 [12.4%]) and minor bleeding from the ovarian pedicle (4 [2.5%]). Splenic puncture required no intervention, and ovarian pedicle bleeding required application of the vessel-sealing device an additional time to control the bleeding. Two ovaries were dropped in the abdominal cavity at the time of removal. Both were retrieved without complication. Conversion to laparotomy was not required for any dog. All dogs were discharged from the hospital within 24 hours after surgery. CONCLUSIONS AND CLINICAL RELEVANCE Laparoscopic ovariectomy in dogs was performed safely by closely supervised novice surgeons, with only minor intraoperative complications encountered and no need for conversion to laparotomy.

Dietary Restriction and AMPK Increase Lifespan via Mitochondrial Network and Peroxisome Remodeling.

Mitochondrial network remodeling between fused and fragmented states facilitates mitophagy, interaction with other organelles, and metabolic flexibility. Aging is associated with a loss of mitochondrial network homeostasis, but cellular processes causally linking these changes to organismal senescence remain unclear. Here, we show that AMP-activated protein kinase (AMPK) and dietary restriction (DR) promote longevity in C. elegans via maintaining mitochondrial network homeostasis and functional coordination with peroxisomes to increase fatty acid oxidation (FAO). Inhibiting fusion or fission specifically blocks AMPK- and DR-mediated longevity. Strikingly, however, preserving mitochondrial network homeostasis during aging by co-inhibition of fusion and fission is sufficient itself to increase lifespan, while dynamic network remodeling is required for intermittent fasting-mediated longevity. Finally, we show that increasing lifespan via maintaining mitochondrial network homeostasis requires FAO and peroxisomal function. Together, these data demonstrate that mechanisms that promote mitochondrial homeostasis and plasticity can be targeted to promote healthy aging.

The nurse's role in contributing to new device development.

Nurses are in an ideal position to use their clinical observations to highlight unmet needs in relation to device use. This paper explores issues that relate to medical devices. An overview is given of the medical device field and examples are given from a survey of the healthcare literature to determine the level of user involvement in device development.

AMPK as a Pro-longevity Target.

Chronic, age-associated diseases are already among the leading causes of morbidity and death in the world, a problem exacerbated by the rapidly rising proportion of elderly in the global population. This emergent epidemic represents the next great challenge for biomedical science and public health. Fortunately, decades of studies into the biology of aging have provided a head start by revealing an evolutionarily conserved network of genes that controls the rate and quality of the aging process itself and which can thereby be targeted for protection against age-onset disease. A number of dietary, genetic, and pharmacological interventions, including dietary restriction (DR) and the biguanide metformin, can extend healthy lifespan and reduce the incidence of multiple chronic conditions. Many of these interventions recurrently involve a core network of nutrient sensors: AMP-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR), the insulin/insulin-like growth factor signaling pathway (IIS), and the sirtuins. Here, we will summarize how AMPK acts downstream of these pro-longevity interventions and within this network of nutrient sensors to control the cell and physiological processes important for defining how well we age.

Comparison of NK-1 Receptor Antagonist (Maropitant) to Morphine as a Pre-Anaesthetic Agent for Canine Ovariohysterectomy.

OBJECTIVE: To compare the NK-1 receptor antagonist maropitant to morphine during and after surgery in dogs undergoing ovariohysterectomy (OHE). METHODS: 30 healthy female dogs were randomly divided to receive either a pre-anaesthetic dose of morphine (0.5 mg/kg SQ) or maropitant (1 mg/kg, SQ) prior to OHE. Anaesthesia was induced with propofol and maintained with isoflurane. Expired isoflurane concentration, heart rate (HR), systolic arterial pressure (SAP) and respiratory rate were measured. Post-operative pain scores and appetite were evaluated during the recovery period. Rescue analgesia (morphine 0.1 mg/kg IV) was administered as needed post-operatively based on blinded pain score assessments. RESULTS: Although clinically comparable; during surgical stimulation, the maropitant group had lower HR (108±18 vs 115±24 bpm; p = 0.04), lower SAP (114±23 vs 125±23 mmHg; p = 0.003) and required slightly lower percent of isoflurane anaesthetic (1.35±0.2 vs 1.51±0.4%; p = 0.005), when compared to the morphine group. In the recovery period, the maropitant group had lower pain scores at extubation (1.7±0.7 vs 3.4±2.3; p = 0.0001) and were more likely to eat within 3 hours after extubation (64.7 vs 15.3%). However, post-operative rescue analgesia requirements were similar between groups. All other measured parameters were similar between groups. The overall difference observed between groups was small and all monitored and measured parameters were within the expected range for anesthetized dogs. CLINICAL SIGNIFICANCE: No major differences in cardiorespiratory parameters or anaesthetic requirements were observed between maropitant and morphine when used as a pre-anesthetic agent for OHE. Further studies are necessary to fully elucidate the benefits of maropitant as a pre-anaesthetic agent for canine OHE.

DNP-KLH Yields Changes in Leukocyte Populations and Immunoglobulin Isotype Use with Different Immunization Routes in Zebrafish.

Distinct methods are required for inducing mucosal versus systemic immunity in mammals for vaccine protection at the tissues most commonly breached by pathogens. Understanding of mucosal immunization in teleost fish is needed to combat aquaculture disease, understand emerging ecological threats, and know how vertebrate adaptive immunity evolved. Here, we quantitatively measured expression levels of IgM as well as the teleost mucosal immunoglobulin, IgZ/IgT, in zebrafish given an antigen systemically via intraperitoneal (i.p.) injection or mucosally via bath immersion. Both immunoglobulin isotypes and the B cell activating factor gene transcription was induced in fish injected with antigen as compared to saline injected or antigen immersed fish, though these failed to reach statistical significance. Here we provide additional reference hematology for this model species. Differential blood counts revealed a greater lymphocyte percentage in both i.p. and immersed fish, with increase in large lymphocyte counts and decrease in neutrophils. These humoral adaptive gene transcription and cytological data should provide a foundation for more studies connecting immunology in this dominant developmental and genetic fish model to other species where mucosal immunization is of greater commercial importance.

SIRT3: A Central Regulator of Mitochondrial Adaptation in Health and Disease.

SIRT3 is a NAD(+)-dependent deacetylase that regulates the function of numerous mitochondrial proteins with roles in metabolism, oxidative stress, and cell survival. It is emerging as an instrumental regulator of the mitochondrial adaptive responses to stress, including metabolic reprogramming and enhancing antioxidant defense mechanisms. Here, we discuss the role that SIRT3 plays at both a cellular and physiological level and consider its involvement in disease. Mitochondrial dysfunction is a key contributing factor in many diseases; however, the mechanisms involved are often not well understood, and few targeted therapies exist. If manipulation of SIRT3 proves to be beneficial in disease states, then it could be a promising target for novel therapies.

CNS SIRT3 expression is altered by reactive oxygen species and in Alzheimer's disease.

Progressive mitochondrial dysfunction contributes to neuronal degeneration in age-mediated disease. An essential regulator of mitochondrial function is the deacetylase, sirtuin 3 (SIRT3). Here we investigate a role for CNS Sirt3 in mitochondrial responses to reactive oxygen species (ROS)- and Alzheimer's disease (AD)-mediated stress. Pharmacological augmentation of mitochondrial ROS increases Sirt3 expression in primary hippocampal culture with SIRT3 over-expression being neuroprotective. Furthermore, Sirt3 expression mirrors spatiotemporal deposition of ß-amyloid in an AD mouse model and is also upregulated in AD patient temporal neocortex. Thus, our data suggest a role for SIRT3 in mechanisms sensing and tackling ROS- and AD-mediated mitochondrial stress.