c-Abl Phosphorylates MFN2 to Regulate Mitochondrial Morphology in Cells under Endoplasmic Reticulum and Oxidative Stress, Impacting Cell Survival and Neurodegeneration

The endoplasmic reticulum is a subcellular organelle key in the control of synthesis, folding, and sorting of proteins. Under endoplasmic reticulum stress, an adaptative unfolded protein response is activated; however, if this activation is prolonged, cells can undergo cell death, in part due to oxidative stress and mitochondrial fragmentation. Here, we report that endoplasmic reticulum stress activates c-Abl tyrosine kinase, inducing its translocation to mitochondria. We found that endoplasmic reticulum stress-activated c-Abl interacts with and phosphorylates the mitochondrial fusion protein MFN2, resulting in mitochondrial fragmentation and apoptosis. Moreover, the pharmacological or genetic inhibition of c-Abl prevents MFN2 phosphorylation, mitochondrial fragmentation, and apoptosis in cells under endoplasmic reticulum stress. Finally, in the amyotrophic lateral sclerosis mouse model, where endoplasmic reticulum and oxidative stress has been linked to neuronal cell death, we demonstrated that the administration of c-Abl inhibitor neurotinib delays the onset of symptoms. Our results uncovered a function of c-Abl in the crosstalk between endoplasmic reticulum stress and mitochondrial dynamics via MFN2 phosphorylation.

Impact of a Multifaceted, Pharmacist-Led Intervention on Psychotropic Medication Use for Residents of Aged Care Facilities: A Parallel Cluster Randomized Controlled Trial

OBJECTIVE

To investigate the effect of a multifaceted intervention on reduction in psychotropic medication use, falls, agitation, emergency department (ED) visits, and hospitalization in residential aged care facilities (RACFs).

DESIGN

Parallel cluster randomized controlled trial. RACFs were randomized to the multifaceted intervention, Medication Management Consultancy (MMC) (n = 5) or control (n = 6) groups. MMC, comprising online education, medication audits, and resources on psychotropic medications and nonpharmacological strategies, educates RACF staff to help reduce the use of antipsychotic medication among RACF residents through a comprehensive understanding of behavioral and psychological symptoms of dementia.

SETTING AND PARTICIPANTS

A total of 439 residents from 11 RACFs in Western Australia.

METHODS

The primary outcome was change in monthly total equivalent doses (mg) of antipsychotic, antidepressant, and benzodiazepine medication use over 12 months compared with a control group. Clinical outcomes included falls, restraints, agitation, ED visits, hospitalization, and knowledge of psychotropic medications among RACF staff at pre- and postintervention were measured. The duration of the intervention was 3 to 6 months. Data were collected at T0 (baseline), T1 (6 months), and T2 (12 months).

RESULTS

The MMC group showed a significant 44% reduction in antipsychotic use compared with the control group at T1 (incidence rate ratios [IRR], 0.56; 95% CI, 0.32-0.99; P = .048) and also significantly reduced the number of ED visits at T1 (IRR, 0.15; 95% CI, 0.06-0.35; P < .0005) and T2 (IRR, 0.04; 95% CI, 0.01-0.13; P < .0005). Staff knowledge about psychotropic medications improved significantly from T0 to T1 and from T0 to T2. Reduction in antidepressant use at either T1 or T2 and benzodiazepine use, compared with control, at T1 and T2 were not significantly different. Other clinical outcomes showed limited impact.

CONCLUSION AND IMPLICATIONS

The MMC intervention reduced the use of antipsychotics and ED visits and improved staff knowledge in RACFs, which impacts the safety and quality of aged care in Australia.

Beta 3-adrenoceptor agonism ameliorates early-life stress-induced visceral hypersensitivity in male rats

Visceral hypersensitivity, a hallmark of disorders of the gut-brain axis, is associated with exposure to early-life stress (ELS). Activation of neuronal β3-adrenoceptors (AR) has been shown to alter central and peripheral levels of tryptophan and reduce visceral hypersensitivity. In this study, we aimed to determine the potential of a β3-AR agonist in reducing ELS-induced visceral hypersensitivity and possible underlying mechanisms. Here, ELS was induced using the maternal separation (MS) model, where Sprague Dawley rat pups were separated from their mother in early life (postnatal day 2-12). Visceral hypersensitivity was confirmed in adult offspring using colorectal distension (CRD). CL-316243, a β3-AR agonist, was administered to determine anti-nociceptive effects against CRD. Distension-induced enteric neuronal activation as well as colonic secretomotor function were assessed. Tryptophan metabolism was determined both centrally and peripherally. For the first time, we showed that CL-316243 significantly ameliorated MS-induced visceral hypersensitivity. Furthermore, MS altered plasma tryptophan metabolism and colonic adrenergic tone, while CL-316243 reduced both central and peripheral levels of tryptophan and affected secretomotor activity in the presence of tetrodotoxin. This study supports the beneficial role of CL-316243 in reducing ELS-induced visceral hypersensitivity, and suggests that targeting the β3-AR can significantly influence gut-brain axis activity through modulation of enteric neuronal activation, tryptophan metabolism, and colonic secretomotor activity which may synergistically contribute to offsetting the effects of ELS.

Age-associated deficits in social behaviour are microbiota-dependent

Aging is associated with remodelling of immune and central nervous system responses resulting in behavioural impairments including social deficits. Growing evidence suggests that the gut microbiome is also impacted by aging, and we propose that strategies to reshape the aged gut microbiome may ameliorate some age-related effects on host physiology. Thus, we assessed the impact of gut microbiota depletion, using an antibiotic cocktail, on aging and its impact on social behavior and the immune system. Indeed, microbiota depletion in aged mice eliminated the age-dependent deficits in social recognition. We further demonstrate that although age and gut microbiota depletion differently shape the peripheral immune response, aging induces an accumulation of T cells in the choroid plexus, that is partially blunted following microbiota depletion. Moreover, an untargeted metabolomic analysis revealed age-dependent alterations of cecal metabolites that are reshaped by gut microbiota depletion. Together, our results suggest that the aged gut microbiota can be specifically targeted to affect social deficits. These studies propel the need for future investigations of other non-antibiotic microbiota targeted interventions on age-related social deficits both in animal models and humans.

Caspase-8 and FADD prevent spontaneous ZBP1 expression and necroptosis

The absence of Caspase-8 or its adapter, Fas-associated death domain (FADD), results in activation of receptor interacting protein kinase-3 (RIPK3)- and mixed-lineage kinase-like (MLKL)-dependent necroptosis in vivo. Here, we show that spontaneous activation of RIPK3, phosphorylation of MLKL, and necroptosis in Caspase-8- or FADD-deficient cells was dependent on the nucleic acid sensor, Z-DNA binding protein-1 (ZBP1). We genetically engineered a mouse model by a single insertion of FLAG tag onto the N terminus of endogenous MLKL (Mlkl^FLAG/FLAG), creating an inactive form of MLKL that permits monitoring of phosphorylated MLKL without activating necroptotic cell death. Casp8^-/-Mlkl^FLAG/FLAG mice were viable and displayed phosphorylated MLKL in a variety of tissues, together with dramatically increased expression of ZBP1 compared to Casp8^+/+ mice. Studies in vitro revealed an increased expression of ZBP1 in cells lacking FADD or Caspase-8, which was suppressed by reconstitution of Caspase-8 or FADD. Ablation of ZBP1 in Casp8^-/-Mlkl^FLAG/FLAG mice suppressed spontaneous MLKL phosphorylation in vivo. ZBP1 expression and downstream activation of RIPK3 and MLKL in cells lacking Caspase-8 or FADD relied on a positive feedback mechanism requiring the nucleic acid sensors cyclic GMP-AMP synthase (cGAS), stimulator of interferon genes (STING), and TBK1 signaling pathways. Our study identifies a molecular mechanism whereby Caspase-8 and FADD suppress spontaneous necroptotic cell death.

Sublethal cytochrome c release generates drug-tolerant persister cells

Drug-tolerant persister cells (persisters) evade apoptosis upon targeted and conventional cancer therapies and represent a major non-genetic barrier to effective cancer treatment. Here, we show that cells that survive treatment with pro-apoptotic BH3 mimetics display a persister phenotype that includes colonization and metastasis in vivo and increased sensitivity toward ferroptosis by GPX4 inhibition. We found that sublethal mitochondrial outer membrane permeabilization (MOMP) and holocytochrome c release are key requirements for the generation of the persister phenotype. The generation of persisters is independent of apoptosome formation and caspase activation, but instead, cytosolic cytochrome c induces the activation of heme-regulated inhibitor (HRI) kinase and engagement of the integrated stress response (ISR) with the consequent synthesis of ATF4, all of which are required for the persister phenotype. Our results reveal that sublethal cytochrome c release couples sublethal MOMP to caspase-independent initiation of an ATF4-dependent, drug-tolerant persister phenotype.

Bone Turnover Markers Including Undercarboxylated Osteocalcin Are Associated With Mortality Risk in Older Men

Osteocalcin in its undercarboxylated form (ucOC) may influence diabetes risk; however, its relationship with all-cause and cause-specific mortality is unclear. Whether other bone turnover markers (BTMs) are associated with mortality risk differently from ucOC also remains uncertain. Our aim was to determine associations of serum ucOC with all-cause and cause-specific mortality and compare these with the corresponding associations of serum total osteocalcin (TOC), procollagen type I N-propeptide (PINP), and collagen type 1 C-terminal cross-linked telopeptide (CTX) in older men. We conducted a prospective cohort study of 3871 community-dwelling men, aged 77.0 ± 3.6 years at baseline, followed for a median of 12.3 years. Exposure variables were ucOC, TOC, PINP, and CTX concentrations assayed in serum. Outcomes were incidence of all deaths and deaths due to cardiovascular disease (CVD) or cancer, ascertained using death registry data. Cox regression analyses adjusted for cardiovascular risk factors and prevalent CVD and for prevalent cancer in analyses of cancer-related mortality. Higher concentrations of ucOC, PINP, and CTX were associated with all-cause mortality (hazard ratio [HR] per 1 standard deviation increase: ucOC 1.12, 95% confidence interval [CI] 1.06-1.18, p < 0.001; PINP HR = 1.06, 95% CI 1.01-1.11, p = 0.009; CTX HR = 1.13, 95% CI 1.08-1.19, p < 0.001), but TOC was not associated. Similar results were found after excluding men with an incident fracture during follow-up. Higher ucOC and CTX were associated with CVD mortality (ucOC HR per 1 SD increase 1.13, 95% CI 1.05-1.22, p = 0.001; CTX HR = 1.12, 95% CI 1.04-1.20, p = 0.003), but this result was not significant in competing risks analysis. Higher CTX was also associated with cancer mortality (HR = 1.12, 95% CI 1.01-1.23, p = 0.024). In conclusion, in older men, higher bone turnover, assessed by BTMs including ucOC, is a biomarker for all-cause mortality risk. Undercarboxylated osteocalcin was a more informative biomarker for this outcome than TOC. Higher CTX was associated with all-cause and cancer-related mortality. Further evaluation of causality and potential underlying mechanisms is warranted. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Distinct post-sepsis induced neurochemical alterations in two mouse strains

Sepsis associated encephalopathy, occurs in 70% of severe septic cases, following which survivors exhibit long-term cognitive impairment or global loss of cognitive function. Currently there is no clearly defined neurochemical basis of septic encephalopathy. Moreover, the lingering neurological complications associated with the severe acute respiratory syndrome CoV 2 (SARS-CoV-2) and the significant worsening in outcomes for those individuals with SARS-Cov-2 following sepsis underscore the need to define factors underlying the susceptibility to acute toxic encephalitis. In this study, differential neurochemical sequelae in response to sepsis (lipopolysaccharide (LPS)-induced endotoxemia and caecal ligation and puncture (CLP)), were evaluated in two inbred mouse strains, known to differ in behaviour, immune profile, and neurotransmitter levels, namely BALB/c and C57BL/6J. It was hypothesized that these strains would differ in sepsis severity, cytokine profile, peripheral tryptophan metabolism and central monoamine turnover. BALB/c mice exhibited more pronounced sickness behavioural scores, hypothermia, and significant upregulation of cytokines in the LPS model relative to C57BL/6J mice. Increased plasma kynurenine/tryptophan ratio, hippocampal serotonin and brainstem dopamine turnover were evident in both strains, but the magnitude was greater in BALB/c mice. In addition, CLP significantly enhanced kynurenine levels and hippocampal serotonergic and dopaminergic neurotransmission in C57BL/6J mice. Overall, these studies depict consistent changes in kynurenine, serotonin, and dopamine post sepsis. Further evaluation of these monoamines in the context of septic encephalopathy and cognitive decline is warranted. Moreover, these data suggest the continued evaluation of altered peripheral kynurenine metabolism as a potential blood-based biomarker of sepsis.

Atrial Arrhythmia Ablation in Patients With D-Transposition of the Great Arteries and Atrial Switch

BACKGROUND

Patients with D-transposition of the great arteries and atrial switch have a high incidence of atrial arrhythmias. We sought to analyze the arrhythmia substrate, ablation strategies, and outcomes for catheter ablation in this population.

METHODS

An in-depth analysis of all clinical and procedural data in patients with D-transposition of the great arteries, atrial baffles, and atrial arrhythmia ablation was performed.

RESULTS

A cohort of 32 patients (72% male, mean age 38±7 years) underwent ablation for non-AV nodal reentrant tachycardia atrial arrhythmias, and 4 patients underwent AV nodal reentrant tachycardia ablation. Cavotricuspid isthmus flutter (CTI-flutter) was the most common arrhythmia, encountered in 75% of patients, followed by scar-related intraatrial reentrant tachycardia (non-CTI intraatrial reentrant tachycardia, 53%) and focal atrial tachycardia (focal atrial tachycardia, 6%). Among the 32 patients, 26 underwent 31 procedures at our institution. For patients with prior outside intervention, the index ablation at our institution revealed CTI-dependent flutter in 3/5 cases. However, redo ablation after an index ablation with demonstrated bidirectional CTI block revealed different/new arrhythmia substrates (80% non-CTI intraatrial reentrant tachycardia, 40% focal atrial tachycardia). Achieving bidirectional block across the CTI often required ablating on both sides of the baffle (retroaortic access, 81%; using a baffle leak, 11.5%; or transbaffle puncture, 7.7%). Combined approaches were necessary in 19% to reach the critical tissue. Acute procedural success was 81%, and recurrence was documented in 58% of patients. Despite recurrence, clinical arrhythmia burden was significantly reduced post-ablation (P<0.001), with rare episodes, amenable to antiarrhythmic therapy. Redo ablation was required in 5 (19%) patients and uncovered new arrhythmia substrates. AV nodal reentrant tachycardia ablation also required transbaffle approaches in 3/4 patients.

CONCLUSIONS

CTI-dependent flutter was the most common arrhythmia in patients with Dextro-Transposition of the Great Arteries and atrial switch. Transbaffle approaches were often necessary, and, provided that bidirectional CTI block was achieved at the index ablation, late recurrence was due to different arrhythmia mechanisms. Despite recurrence, ablation was associated with significant clinical improvement.

Differing Methodologies Are Required to Estimate Prevalence of Dementia: Single Study Types Are No Longer Reliable

Population-based surveys were used to estimate community prevalence of dementia, but have low response fractions due, among other things, to difficulties in obtaining informed consent from people with diminished capacity. Cohort studies of younger people are subject to recruitment bias and non-random drop-outs. Dementia registries can delineate sub-types of dementia but have limited population coverage and are costly to maintain. Administrative datasets have low costs but may be subject to selection bias and uncertain sensitivity. We propose that astute combination of methodologies, including assessment of coverage and validity of administrative datasets, is the most cost-effective process to estimate and monitor community prevalence.

Investigating the potential of fish oil as a nutraceutical in an animal model of early life stress

Background: Early life stress is a key predisposing factor for depression and anxiety disorders. Selective serotonin re-uptake inhibitors (SSRI) are frequently used as the first line of pharmacology treatment for depression but have several negative qualities, i.e. a delay or absence of effectiveness and negative side-effects. Therefore, there is a growing need for new nutraceutical-based strategies to blunt the effects of adverse-life events.Objectives: This study aimed to use the maternal separation model in rats to test the efficacy of fish oil dietary supplementation, on its own and in conjunction with the SSRI anti-depressant fluoxetine, as a treatment for depressive and anxiety-like symptoms associated with early life stress.Methods: Behavioural tests (open field test, elevated plus maze test and forced swim test) and biochemical markers (corticosterone, BDNF, brain fatty acids and short chain fatty acids) were used to analyse the effects of the dietary treatments. Gut microbial communities and relating metabolites (SCFA) were analysed to investigate possible changes in the microbiota-gut-brain axis.Results: Maternally separated rats showed depressive-like behaviours in the forced swim and open field tests. These behaviours were prevented significantly by fluoxetine administration and in part by fish oil supplementation. Associated biochemical changes reported include altered brain fatty acids, significantly lower plasma corticosterone levels (AUC) and reduced brain stem serotonin turnover, compared to untreated, maternally separated (MS) rats. Untreated MS animals had significantly lower ratios of SCFA producers such as Caldicoprobacteraceae, Streptococcaceae, Rothia, Lachnospiraceae_NC2004_group, and Ruminococcus_2, along with significantly reduced levels of total SCFA compared to non-separated animals. Compared to untreated MS animals, animals fed fish oil had significantly higher Bacteroidetes and Prevotellaceae and reduced levels of butyrate, while fluoxetine treatment resulted in significantly higher levels of Neochlamydia, Lachnoclostridium, Acetitomaculum and Stenotrophomonas and, acetate and propionate.Conclusion: Despite the limitations in extrapolating from animal behavioural data and the notable differences in pharmacokinetics between rodents and humans, the results of this study provide a further advancement into the understanding of some of the complex systems within which nutraceuticals and pharmaceuticals effect the microbiota-gut-brain axis.

Conservation psychology strategies for collaborative planning and impact evaluation

Conservation psychology principles can be useful for aligning organizations and scaling up conservation programs to increase impact while strategically engaging partners and communities. We can use findings and recommendations from conservation psychology to inform organizational collaborations between zoos and aquariums to maximize efficiency and coordination. In this study, we developed and evaluated a collaborative conservation initiative for monarch butterflies built with conservation psychology principles. We present our process for collaborative program planning and the resultant collective conservation plan as well as our formative evaluation findings after 1-year of collaboration. We share best practices for group facilitation and conservation planning along with our evaluation instruments to support future collaborative conservation initiatives.

Dietary Milk Phospholipids Attenuate Chronic Stress-Induced Changes in Behavior and Endocrine Responses across the Lifespan

SCOPE

Increasing scientific evidence is validating the use of dietary strategies to support and improve brain health throughout the lifespan, with tailored nutritional interventions catering for specific life stages. Dietary phospholipid supplementations in early life and adulthood are shown to alleviate some of the behavioral consequences associated with chronic stress. This study aims to explore the protective effects of a tailored phospholipid-enriched buttermilk on behavioral and endocrine responses induced by chronic psychosocial stress in adulthood, and to compare these effects according to the life stage at which the supplementation is started.

METHODS AND RESULTS

A novel developed phospholipid-enriched dairy product is assessed for its effects on social, anxiety- and depressive-like behaviors, as well as the stress response and cognitive performance following chronic psychosocial stress in C57BL/6J mice, with supplementation beginning in adulthood or early life. Milk phospholipid supplementation from birth protects adult mice against chronic stress-induced changes in endocrine response to a subsequent acute stressor and reduces innate anxiety-like behavior in non-stressed animals. When starting in adulthood, the dietary intervention reverses the anxiety-like phenotype caused by chronic stress exposure.

CONCLUSION

Dairy-derived phospholipids exert differential protective effects against chronic psychosocial stress depending on the targeted life stage and duration of the dietary supplementation.

Interlaboratory collaboration to determine the performance of the Randox food diagnostics biochip array technology for the simultaneous quantitative detection of seven mycotoxins in feed

An inter-laboratory collaborative study was performed to evaluate the performance of the Biochip Array Technology (BAT) Myco 7 method. The Myco 7 Array is a method which simultaneously and quantitatively detects 20 mycotoxins including aflatoxins B1, B2, G1 and G2, ochratoxin A, deoxynivalenol, zearalenone, fumonisin B1, B2 and B3 and T-2 and HT-2 toxin. The BAT Myco 7 method was collaboratively evaluated by nine government and private Association of American Feed Control Officials (AAFCO) laboratories. Samples were analysed in a proficiency testing round format. Seventeen blind samples were analysed on the same equipment using Myco 7 kits. 99% of the results fell within an acceptable Z-score range of -2|<Z<|+2. Deoxynivalenol had a 100% Z-score pass rate, while a 99% pass was recorded for aflatoxins, zearalenone, ochratoxin A and fumonisins. T-2 toxin had a 97% Z-score pass rate. HorRat analysis for reproducibility used a range of 0.3<|HorRat|≤2. The target was met for deoxynivalenol, zearalenone, T-2 and HT-2 toxin, and aflatoxins B1, B2, G1 and G2 assays. Fumonisins and ochratoxin A assays had a 93% and 94% pass, respectively. The reproducibility co-efficiency of variation was between 16 and 20% meeting set criterion of <40% and is, therefore, fit-for-purpose for use in the AAFCO control programs for mycotoxins.

Estrous cycle and ovariectomy-induced changes in visceral pain are microbiota-dependent

Visceral hypersensitivity (VH) is a hallmark of many functional gastrointestinal disorders including irritable bowel syndrome and is categorized by a dull, diffuse sensation of abdominal pain. Recently, the gut microbiota has been implicated in VH in male mice, but the effects in females have yet to be explored fully. To this end, we now show that somewhat surprisingly, female germ-free mice have similar visceral pain responses to colorectal distension (CRD) as their conventional controls. However, we show that although sensitivity to CRD is estrous cycle stage-dependent in conventional mice, it is not in germ-free mice. Further, ovariectomy (OVX) induced VH in conventional but not germ-free mice, and induced weight gain regardless of microbiota status. Finally, we show that estrogen-replacement ameliorated OVX-induced VH. Taken together, this study provides evidence for a major role of female sex hormones and the gut microbiota in sensation of visceral pain in females.

Microbiota from young mice counteracts selective age-associated behavioral deficits

The gut microbiota is increasingly recognized as an important regulator of host immunity and brain health. The aging process yields dramatic alterations in the microbiota, which is linked to poorer health and frailty in elderly populations. However, there is limited evidence for a mechanistic role of the gut microbiota in brain health and neuroimmunity during aging processes. Therefore, we conducted fecal microbiota transplantation from either young (3-4 months) or old (19-20 months) donor mice into aged recipient mice (19-20 months). Transplant of a microbiota from young donors reversed aging-associated differences in peripheral and brain immunity, as well as the hippocampal metabolome and transcriptome of aging recipient mice. Finally, the young donor-derived microbiota attenuated selective age-associated impairments in cognitive behavior when transplanted into an aged host. Our results reveal that the microbiome may be a suitable therapeutic target to promote healthy aging.

Mapping O2 concentration in ex-vivo tissue samples on a fast PLIM macro-imager

O2 PLIM microscopy was employed in various studies, however current platforms have limitations in sensitivity, image acquisition speed, accuracy and general usability. We describe a new PLIM imager based on the Timepix3 camera (Tpx3cam) and its application for imaging of O2 concentration in various tissue samples stained with a nanoparticle based probe, NanO2-IR. Upon passive staining of mouse brain, lung or intestinal tissue surface with minute quantities of NanO2-IR or by microinjecting the probe into the lumen of small or large intestine fragments, robust phosphorescence intensity and lifetime signals were produced, which allow mapping of O2 in the tissue within 20 s. Inhibition of tissue respiration or limitation of O2 diffusion to tissue produced the anticipated increases or decreases in O2 levels, respectively. The difference in O2 concentration between the colonic lumen and air-exposed serosal surface was around 140 µM. Furthermore, subcutaneous injection of 5 µg of the probe in intact organs (a paw or tail of sacrificed mice) enabled efficient O2 imaging at tissue depths of up to 0.5 mm. Overall, the PLIM imager holds promise for metabolic imaging studies with various ex vivo models of animal tissue, and also for use in live animals.

Noncanonical function of an autophagy protein prevents spontaneous Alzheimer's disease

Noncanonical functions of autophagy proteins have been implicated in neurodegenerative conditions, including Alzheimer's disease (AD). The WD domain of the autophagy protein Atg16L is dispensable for canonical autophagy but required for its noncanonical functions. Two-year-old mice lacking this domain presented with robust β-amyloid (Aβ) pathology, tau hyperphosphorylation, reactive microgliosis, pervasive neurodegeneration, and severe behavioral and memory deficiencies, consistent with human disease. Mechanistically, we found this WD domain was required for the recycling of Aβ receptors in primary microglia. Pharmacologic suppression of neuroinflammation reversed established memory impairment and markers of disease pathology in this novel AD model. Therefore, loss of the Atg16L WD domain drives spontaneous AD in mice, and inhibition of neuroinflammation is a potential therapeutic approach for treating neurodegeneration and memory loss. A decline in expression of ATG16L in the brains of human patients with AD suggests the possibility that a similar mechanism may contribute in human disease.

Warfarin therapy in atrial fibrillation: assessment of patient knowledge of risks and benefits

Patients with atrial fibrillation are at an increased risk for stroke, and many benefits from anticoagulation. Despite the emergence of direct oral anticoagulants, many patients continue to rely on warfarin for their anticoagulation due to logistical, pharmacokinetic, clinical, or patient preference issues. Previous work has suggested that outcomes of warfarin therapy are related to patient education/knowledge. We assessed knowledge of indications, benefits, and complications of warfarin therapy in 99 randomly selected patients enrolled in the Warfarin Anticoagulation Clinic at the Mayo Clinic in Florida who were taking warfarin for non-valvular atrial fibrillation. Patients were labeled as 'knowledgeable' or 'not knowledgeable' regarding warfarin therapy according to the results of a cross-sectional questionnaire. The majority of patients in both the knowledgeable and not knowledgeable groups displayed understanding that they were taking warfarin for atrial fibrillation (valvular vs non-valvular atrial fibrillation was not an included answer choice). However, there was a clear lack of knowledge amongst patients with atrial fibrillation in both groups about their stroke risk while on and off warfarin, and their risk of major bleeding or adverse events related to their warfarin therapy. There was only a significant difference between the two groups regarding their knowledge of what increases or decreases the risk of bleeding while on warfarin. There was no major difference between the groups with regards to demographic and medical characteristics, except that 'not knowledgeable' patients tended to have more peripheral vascular disease, ulcer disease, and moderate-severe renal disease compared to 'knowledgeable' patients.

Polyphenols selectively reverse early-life stress-induced behavioural, neurochemical and microbiota changes in the rat

There is a growing emphasis on the role of the microbiota-gut-brain axis as modulator of host behaviour and as therapeutic target for neuropsychiatric disorders. In addition, accumulating evidence suggests that early-life stress can exert long-lasting changes on the brain and microbiota, and this early adversity is associated with increased risk for developing depression in later life. The maternal separation (MS) model in rats is a robust paradigm to study the effects of early-life stress on the microbiota-gut-brain axis. Recently, we have shown that polyphenols, naturally occurring compounds associated with several health benefits, have anti-stress effects in in vitro models. In this study, we assess the therapeutic potential of a variety of both flavonoid and non-flavonoid polyphenols in reversing the impact of MS on behaviour and the microbiota-gut-brain axis. Rats underwent a dietary intervention with the naturally-derived polyphenols xanthohumol and quercetin, as well as with a phlorotannin extract for 8 weeks. Treatment with polyphenols prevented the depressive- and anxiety-like behaviours induced by MS, where xanthohumol effects were correlated with rescue of BDNF plasma levels. In addition, MS resulted in altered brain levels of 5-hydroxyindoleacetic acid (5-HIAA) and dopamine, accompanied by abnormal elevation of plasma corticosterone. Although polyphenols did not reverse neurotransmitter imbalance, xanthohumol normalised corticosterone levels in MS rats. Finally, we explored the impact of MS and polyphenolic diets on the gut microbiota. We observed profound changes in microbial composition and diversity produced by MS condition and by xanthohumol treatment. Moreover, functional prediction analysis revealed that MS results in altered enrichment of pathways associated with microbiota-brain interactions that are significantly reversed by xanthohumol treatment. These results suggest that naturally-derived polyphenols exert antidepressant-like effects in MS rats, which mechanisms could be potentially mediated by HPA regulation, BDNF levels rescue and modulation of the microbiota-gut-brain axis.

Caspase-8-Dependent Inflammatory Responses Are Controlled by Its Adaptor, FADD, and Necroptosis

Cell death pathways regulate various homeostatic processes. Autoimmune lymphoproliferative syndrome (ALPS) in humans and lymphoproliferative (LPR) disease in mice result from abrogated CD95-induced apoptosis. Because caspase-8 mediates CD95 signaling, we applied genetic approaches to dissect the roles of caspase-8 in cell death and inflammation. Here, we describe oligomerization-deficient Caspase-8^{F122GL123G/F122GL123G} and non-cleavable Caspase-8^D387A/D387A mutant mice with defective caspase-8-mediated apoptosis. Although neither mouse developed LPR disease, removal of the necroptosis effector Mlkl from Caspase-8^D387A/D387A mice revealed an inflammatory role of caspase-8. Ablation of one allele of Fasl, Fadd, or Ripk1 prevented the pathology of Casp8^D387A/D387AMlkl^-/- animals. Removing both Fadd alleles from these mice resulted in early lethality prior to post-natal day 15 (P15), which was prevented by co-ablation of either Ripk1 or Caspase-1. Our results suggest an in vivo role of the inflammatory RIPK1-caspase-8-FADD (FADDosome) complex and reveal a FADD-independent inflammatory role of caspase-8 that involves activation of an inflammasome.

Metabolome and microbiome profiling of a stress-sensitive rat model of gut-brain axis dysfunction

Stress negatively impacts gut and brain health. Individual differences in response to stress have been linked to genetic and environmental factors and more recently, a role for the gut microbiota in the regulation of stress-related changes has been demonstrated. However, the mechanisms by which these factors influence each other are poorly understood, and there are currently no established robust biomarkers of stress susceptibility. To determine the metabolic and microbial signatures underpinning physiological stress responses, we compared stress-sensitive Wistar Kyoto (WKY) rats to the normo-anxious Sprague Dawley (SD) strain. Here we report that acute stress-induced strain-specific changes in brain lipid metabolites were a prominent feature in WKY rats. The relative abundance of Lactococcus correlated with the relative proportions of many brain lipids. In contrast, plasma lipids were significantly elevated in response to stress in SD rats, but not in WKY rats. Supporting these findings, we found that the greatest difference between the SD and WKY microbiomes were the predicted relative abundance of microbial genes involved in lipid and energy metabolism. Our results provide potential insights for developing novel biomarkers of stress vulnerability, some of which appear genotype specific.

A Comprehensive Plasma Metabolomics Dataset for a Cohort of Mouse Knockouts within the International Mouse Phenotyping Consortium

Mouse knockouts facilitate the study ofgene functions. Often, multiple abnormal phenotypes are induced when a gene is inactivated. The International Mouse Phenotyping Consortium (IMPC) has generated thousands of mouse knockouts and catalogued their phenotype data. We have acquired metabolomics data from 220 plasma samples from 30 unique mouse gene knockouts and corresponding wildtype mice from the IMPC. To acquire comprehensive metabolomics data, we have used liquid chromatography (LC) combined with mass spectrometry (MS) for detecting polar and lipophilic compounds in an untargeted approach. We have also used targeted methods to measure bile acids, steroids and oxylipins. In addition, we have used gas chromatography GC-TOFMS for measuring primary metabolites. The metabolomics dataset reports 832 unique structurally identified metabolites from 124 chemical classes as determined by ChemRICH software. The GCMS and LCMS raw data files, intermediate and finalized data matrices, R-Scripts, annotation databases, and extracted ion chromatograms are provided in this data descriptor. The dataset can be used for subsequent studies to link genetic variants with molecular mechanisms and phenotypes.

Heat-killed lactobacilli alter both microbiota composition and behaviour

Recently it has been proposed to expand the definition of psychobiotics (beneficial bacteria (probiotics) or support for such bacteria (prebiotics) that positively impact mental health) to any exogenous influence whose effect on the brain is bacterially-mediated. This definition would include inactivated microorganisms with anxiolytic and antidepressant effects. The use of inactivated microorganisms has several advantages over living organisms, including no risk of infection in vulnerable individuals and ease of use in terms of storage and delivery options. It has been reported that consumption of inactivated microorganisms can affect behaviour, particularly in chronic or prolonged stress situations, but effects on healthy populations have not been investigated to the same extent. Also, only limited data is available on the effects of inactivated microorganisms on the microbiota of healthy individuals (animal or human). Therefore, we investigated the effect of feeding a standard mouse chow which incorporates ADR-159, a heat-killed fermentate generated by two Lactobacillus strains, on the behaviour and microbiota of healthy mice. Prolonged consumption of ADR-159 diet had no adverse effect on anthropometrics or general health, but the ADR-159 fed animals demonstrated increased sociability and lower baseline corticosterone levels (stress hormone). The diet also led to subtle but significant changes in the microbiota, with less abundant taxa being most affected. The behavioural, biochemical and microbiological results provide a new light on the impact of inactivated microorganisms and their metabolites on the social behaviour and microbiota of healthy mice.

Effect of companion presence on maternal satisfaction during neuraxial catheter placement for labor analgesia: a randomized clinical trial

BACKGROUND

Neuraxial labor analgesia is frequently achieved after placing an epidural catheter under sterile conditions. There is no consensus on the risk versus benefit of allowing a parturient's companion to remain during the procedure. We sought to assess the effect of the presence of a companion on maternal satisfaction and anxiety during neuraxial catheter placement for labor analgesia.

METHODS

Healthy nulliparous parturients planning to receive neuraxial labor analgesia after admission to labor, and who had a companion with them at the time of interview, were randomized to having a companion present or not present in the labor and delivery room during neuraxial catheter placement. Participants completed questionnaires to assess maternal anxiety, pain catastrophizing and health literacy. Satisfaction was scored on 5-point Likert scale (1- highly dissatisfied, 2- dissatisfied, 3- neutral, 4- satisfied, 5- highly satisfied).

RESULTS

A total of 143 participants completed the study. The Wilcoxon-Mann-Whitney odds ratio for a random pair of satisfaction scores for a woman with her companion present compared with companion not present was 1.93 (95% CI 1.30 to 2.81, P=0.001). Anxiety scores were decreased following the procedure (P=0.39) in both groups. Eighty-nine percent of women randomized to companion not present would have preferred to have a companion present (P <0.001) compared with only one with their companion present who would have preferred her companion to be not present (P=0.99).

CONCLUSION

Maternal satisfaction can be improved with the presence of a companion in the labor and delivery room at the time of neuraxial catheter placement for labor analgesia.

Just So Stories about the Evolution of Apoptosis

Apoptosis is a form of active cell death engaged by developmental cues as well as many different cellular stresses in which the dying cell essentially 'packages' itself for removal. The process of apoptotic cell death, as defined at the molecular level, is unique to the Metazoa (animals). Yet active cell death exists in non-animal organisms, and in some cases molecules involved in such death show some sequence similarities to those involved in apoptosis, leading to extensive speculation regarding the evolution of apoptosis. Here, we examine such speculation from the perspective of the functional properties of molecules of the mitochondrial apoptotic cell death pathway. We suggest scenarios for the evolution of one pathway of apoptosis, the mitochondrial pathway, and consider how they might be tested. We conclude with a 'Just So Story' of how the mitochondrial pathway of apoptosis might have evolved during eukaryotic evolution.

ESCRT-III Acts Downstream of MLKL to Regulate Necroptotic Cell Death and Its Consequences

The activation of mixed lineage kinase-like (MLKL) by receptor-interacting protein kinase-3 (RIPK3) results in plasma membrane (PM) disruption and a form of regulated necrosis, called necroptosis. Here, we show that, during necroptosis, MLKL-dependent calcium (Ca²⁺) influx and phosphatidylserine (PS) exposure on the outer leaflet of the plasma membrane preceded loss of PM integrity. Activation of MLKL results in the generation of broken, PM "bubbles" with exposed PS that are released from the surface of the otherwise intact cell. The ESCRT-III machinery is required for formation of these bubbles and acts to sustain survival of the cell when MLKL activation is limited or reversed. Under conditions of necroptotic cell death, ESCRT-III controls the duration of plasma membrane integrity. As a consequence of the action of ESCRT-III, cells undergoing necroptosis can express chemokines and other regulatory molecules and promote antigenic cross-priming of CD8⁺ T cells.

Transferring the blues: Depression-associated gut microbiota induces neurobehavioural changes in the rat

The gut microbiota interacts with the host via neuroimmune, neuroendocrine and neural pathways. These pathways are components of the brain-gut-microbiota axis and preclinical evidence suggests that the microbiota can recruit this bidirectional communication system to modulate brain development, function and behaviour. The pathophysiology of depression involves neuroimmune-neuroendocrine dysregulation. However, the extent to which changes in gut microbiota composition and function mediate the dysregulation of these pathways is unknown. Thirty four patients with major depression and 33 matched healthy controls were recruited. Cytokines, CRP, Salivary Cortisol and plasma Lipopolysaccharide binding protein were determined by ELISA. Plasma tryptophan and kynurenine were determined by HPLC. Fecal samples were collected for 16s rRNA sequencing. A Fecal Microbiota transplantation was prepared from a sub group of depressed patients and controls and transferred by oral gavage to a microbiota-deficient rat model. We demonstrate that depression is associated with decreased gut microbiota richness and diversity. Fecal microbiota transplantation from depressed patients to microbiota-depleted rats can induce behavioural and physiological features characteristic of depression in the recipient animals, including anhedonia and anxiety-like behaviours, as well as alterations in tryptophan metabolism. This suggests that the gut microbiota may play a causal role in the development of features of depression and may provide a tractable target in the treatment and prevention of this disorder.

Local visual perception bias in children with high-functioning autism spectrum disorders; do we have the whole picture?

OBJECTIVE

While local bias in visual processing in children with autism spectrum disorders (ASD) has been reported to result in difficulties in recognizing faces and facially expressed emotions, but superior ability in disembedding figures, associations between these abilities within a group of children with and without ASD have not been explored.

METHODS

Possible associations in performance on the Visual Perception Skills Figure-Ground test, a face recognition test and an emotion recognition test were investigated within 25 8-12-years-old children with high-functioning autism/Asperger syndrome, and in comparison to 33 typically developing children.

RESULTS

Analyses indicated a weak positive correlation between accuracy in Figure-Ground recognition and emotion recognition. No other correlation estimates were significant.

CONCLUSION

These findings challenge both the enhanced perceptual function hypothesis and the weak central coherence hypothesis, and accentuate the importance of further scrutinizing the existance and nature of local visual bias in ASD.

DiPALS: Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis - a randomised controlled trial

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease resulting in death, usually from respiratory failure, within 2-3 years of symptom onset. Non-invasive ventilation (NIV) is a treatment that when given to patients in respiratory failure leads to improved survival and quality of life. Diaphragm pacing (DP), using the NeuRx/4(®) diaphragm pacing system (DPS)™ (Synapse Biomedical, Oberlin, OH, USA), is a new technique that may offer additional or alternative benefits to patients with ALS who are in respiratory failure.

OBJECTIVE

The Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis (DiPALS) trial evaluated the effect of DP on survival over the study duration in patients with ALS with respiratory failure.

DESIGN

The DiPALS trial was a multicentre, parallel-group, open-label, randomised controlled trial incorporating health economic analyses and a qualitative longitudinal substudy.

PARTICIPANTS

Eligible participants had a diagnosis of ALS (ALS laboratory-supported probable, clinically probable or clinically definite according to the World Federation of Neurology revised El Escorial criteria), had been stabilised on riluzole for 30 days, were aged ≥ 18 years and were in respiratory failure. We planned to recruit 108 patients from seven UK-based specialist ALS or respiratory centres. Allocation was performed using 1 : 1 non-deterministic minimisation.

INTERVENTIONS

Participants were randomised to either standard care (NIV alone) or standard care (NIV) plus DP using the NeuRX/4 DPS.

MAIN OUTCOME MEASURES

The primary outcome was overall survival, defined as the time from randomisation to death from any cause. Secondary outcomes were patient quality of life [assessed by European Quality of Life-5 Dimensions, three levels (EQ-5D-3L), Short Form questionnaire-36 items and Sleep Apnoea Quality of Life Index questionnaire]; carer quality of life (EQ-5D-3L and Caregiver Burden Inventory); cost-utility analysis and health-care resource use; tolerability and adverse events. Acceptability and attitudes to DP were assessed in a qualitative substudy.

RESULTS

In total, 74 participants were randomised into the trial and analysed, 37 participants to NIV plus pacing and 37 to standard care, before the Data Monitoring and Ethics Committee advised initial suspension of recruitment (December 2013) and subsequent discontinuation of pacing (on safety grounds) in all patients (June 2014). Follow-up assessments continued until the planned end of the study in December 2014. The median survival (interquartile range) was 22.5 months (lower quartile 11.8 months; upper quartile not reached) in the NIV arm and 11.0 months (6.7 to 17.0 months) in the NIV plus pacing arm, with an adjusted hazard ratio of 2.27 (95% confidence interval 1.22 to 4.25; p = 0.01).

CONCLUSIONS

Diaphragmatic pacing should not be used as a routine treatment for patients with ALS in respiratory failure.

FUTURE WORK

It may be that certain population subgroups benefit from DP. We are unable to explain the mechanism behind the excess mortality in the pacing arm, something the small trial size cannot help address. Future research should investigate the mechanism by which harm or benefit occurs further.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN53817913.

FUNDING

This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 45. See the HTA programme website for further project information. Additional funding was provided by the Motor Neurone Disease Association of England, Wales and Northern Ireland.

Characterization of RIPK3-mediated phosphorylation of the activation loop of MLKL during necroptosis

Mixed lineage kinase domain-like pseudokinase (MLKL) mediates necroptosis by translocating to the plasma membrane and inducing its rupture. The activation of MLKL occurs in a multimolecular complex (the 'necrosome'), which is comprised of MLKL, receptor-interacting serine/threonine kinase (RIPK)-3 (RIPK3) and, in some cases, RIPK1. Within this complex, RIPK3 phosphorylates the activation loop of MLKL, promoting conformational changes and allowing the formation of MLKL oligomers, which migrate to the plasma membrane. Previous studies suggested that RIPK3 could phosphorylate the murine MLKL activation loop at Ser345, Ser347 and Thr349. Moreover, substitution of the Ser345 for an aspartic acid creates a constitutively active MLKL, independent of RIPK3 function. Here we examine the role of each of these residues and found that the phosphorylation of Ser345 is critical for RIPK3-mediated necroptosis, Ser347 has a minor accessory role and Thr349 seems to be irrelevant. We generated a specific monoclonal antibody to detect phospho-Ser345 in murine cells. Using this antibody, a series of MLKL mutants and a novel RIPK3 inhibitor, we demonstrate that the phosphorylation of Ser345 is not required for the interaction between RIPK3 and MLKL in the necrosome, but is essential for MLKL translocation, accumulation in the plasma membrane, and consequent necroptosis.

Streptozotocin-induced type-1-diabetes disease onset in Sprague-Dawley rats is associated with an altered intestinal microbiota composition and decreased diversity

There is a growing appreciation that microbiota composition can significantly affect host health and play a role in disease onset and progression. This study assessed the impact of streptozotocin (STZ)-induced type-1-diabetes (T1D) on intestinal microbiota composition and diversity in Sprague-Dawley rats, compared with healthy controls over time. T1D was induced by injection of a single dose (60 mg STZ kg(-1)) of STZ, administered via the intraperitoneal cavity. Total DNA was isolated from faecal pellets at weeks 0 (pre-STZ injection), 1, 2 and 4 and from caecal content at week 5 from both healthy and T1D groups. High-throughput 16S rRNA sequencing was employed to investigate intestinal microbiota composition. The data revealed that although intestinal microbiota composition between the groups was similar at week 0, a dramatic impact of T1D development on the microbiota was apparent post-STZ injection and for up to 5 weeks. Most notably, T1D onset was associated with a shift in the Bacteroidetes : Firmicutes ratio (P<0.05), while at the genus level, increased proportions of lactic acid producing bacteria such as Lactobacillus and Bifidobacterium were associated with the later stages of T1D progression (P<0.05). Coincidently, T1D increased caecal lactate levels (P<0.05). Microbial diversity was also reduced following T1D (P<0.05). Principle co-ordinate analyses demonstrated temporal clustering in T1D and control groups with distinct separation between groups. The results provide a comprehensive account of how T1D is associated with an altered intestinal microbiota composition and reduced microbial diversity over time.

Antibacterial validation of electrogenerated hypochlorite using carbon-based electrodes

This proof-of-concept study explores the novel use of carbon-based electrodes for the electrochemical generation of hypochlorite and compares the antimicrobial efficacy against commercial hypochlorite solution. Antimicrobial concentrations of hypochlorite were generated using pad-printed carbon and carbon fibre electrodes, yielding up to 0·027% hypochlorite in 60 min and 0·1% hypochlorite in 15 min, respectively, in a nondivided assembly. The minimum inhibitory concentration (MIC) of the electrogenerated hypochlorite produced using carbon fibre electrodes was established for four medically important bacteria (Pseudomonas aeruginosa and Staphylococcus aureus approx. 0·025%, Escherichia coli and Enterococcus faecalis approx. 0·012%) and found to be in agreement with those determined using commercial hypochlorite solution. Therefore, carbon-based electrodes, particularly carbon fibre, have proven effective for the generation of antimicrobial concentrations of hypochlorite. The similarity of the MIC values to commercial hypochlorite solutions suggests that the antimicrobial efficacy is derived from the quantified hypochlorite generated and not due to marked cogeneration of reactive oxygen species, as identified for other assemblies. As such, the application of carbon electrodes may be suitable for the local production of hypochlorite for healthcare antisepsis.

SIGNIFICANCE AND IMPACT OF THE STUDY

Carbon fibre electrodes can rapidly generate antimicrobial concentrations of hypochlorite; as such, these cheap and commercially available electrodes are proposed for the local production of hypochlorite for healthcare antisepsis. Importantly, the antimicrobial properties of the electrochemically generated hypochlorite mirror those of commercial hypochlorite, suggesting this is not enhanced by the cogeneration of reactive oxygen species. This illustrates the potential use of disposable carbon electrodes for localized small-volume production of hypochlorite for surface and skin cleansing, and opens a broader scope of research into the exploitation of carbon electrodes for this application.

Investigation of Cardiovascular Effects of Tetrahydro-β-carboline sstr3 antagonists

Antagonism of somatostatin subtype receptor 3 (sstr3) has emerged as a potential treatment of Type 2 diabetes. Unfortunately, the development of our first preclinical candidate, MK-4256, was discontinued due to a dose-dependent QTc (QT interval corrected for heart rate) prolongation observed in a conscious cardiovascular (CV) dog model. As the fate of the entire program rested on resolving this issue, it was imperative to determine whether the observed QTc prolongation was associated with hERG channel (the protein encoded by the human Ether-à-go-go-Related Gene) binding or was mechanism-based as a result of antagonizing sstr3. We investigated a structural series containing carboxylic acids to reduce the putative hERG off-target activity. A key tool compound, 3A, was identified from this SAR effort. As a potent sstr3 antagonist, 3A was shown to reduce glucose excursion in a mouse oGTT assay. Consistent with its minimal hERG activity from in vitro assays, 3A elicited little to no effect in an anesthetized, vagus-intact CV dog model at high plasma drug levels. These results afforded the critical conclusion that sstr3 antagonism is not responsible for the QTc effects and therefore cleared a path for the program to progress.

Caspase-8, RIPK1 and FADD regulate cell death and caspase-1 activation during yersinia infection (INM3P.438)

Programmed cell death is an evolutionarily conserved response to infection that can promote host defense or microbial virulence. Pathogens manipulate various immune signaling pathways through the activity of specific virulence factors that access the host cell cytosol. Cell death is a major consequence of infection with pathogenic Y. pseudotuberculosis and requires the effector YopJ, a potent inhibitor of NF-κB and MAPK signaling. However, the pathways that regulate cell death in response to Yersinia infection and the precise mechanism by which cell death mediates protective immunity are not well understood. We find a novel requirement for caspase-8, receptor interacting protein 1 (RIPK1) and Fas-associated protein with death domain (FADD) in Yersinia-induced cell death and pro-inflammatory caspase-1 activation. Moreover, mice deficient in caspase-8 were highly susceptible to Yersinia infection and were unable to sustain innate cytokine production. We hypothesize that activation of these pathways during Yersinia infection may induce specific pro-inflammatory signals that shape innate and adaptive responses and promote microbial clearance.

Home telemonitoring or structured telephone support programmes after recent discharge in patients with heart failure: systematic review and economic evaluation

BACKGROUND

Remote monitoring (RM) strategies have the potential to deliver specialised care and management to patients with heart failure (HF).

OBJECTIVE

To determine the clinical effectiveness and cost-effectiveness of home telemonitoring (TM) or structured telephone support (STS) strategies compared with usual care for adult patients who have been recently discharged (within 28 days) from acute care after a recent exacerbation of HF.

DATA SOURCES

Fourteen electronic databases (including MEDLINE, EMBASE, PsycINFO and The Cochrane Library) and research registers were searched to January 2012, supplemented by hand-searching relevant articles and contact with experts. The review included randomised controlled trials (RCTs) or observational cohort studies with a contemporaneous control group that included the following RM interventions: (1) TM (including cardiovascular implanted monitoring devices) with medical support provided during office hours or 24/7; (2) STS programmes delivered by human-to-human contact (HH) or human-to-machine interface (HM).

REVIEW METHODS

A systematic review and network meta-analysis (where appropriate) of the clinical evidence was carried out using standard methods. A Markov model was developed to evaluate the cost-effectiveness of different RM packages compared with usual care for recently discharged HF patients. TM 24/7 or using cardiovascular monitoring devices was not considered in the economic model because of the lack of data and/or unsuitability for the UK setting. Given the heterogeneity in the components of usual care and RM interventions, the cost-effectiveness analysis was performed using a set of costing scenarios designed to reflect the different configurations of usual care and RM in the UK.

RESULTS

The literature searches identified 3060 citations. Six RCTs met the inclusion criteria and were added to the 15 trials identified from the previous systematic reviews giving a total of 21 RCTs included in the systematic review. No trials of cardiovascular implanted monitoring devices or observational studies met the inclusion criteria. The methodological quality of the studies varied widely and reporting was generally poor. Compared with usual care, RM was beneficial in reducing all-cause mortality for STS HH [hazard ratio (HR) 0.77, 95% credible interval (CrI) 0.55 to 1.08], TM during office hours (HR 0.76, 95% CrI 0.49 to 1.18) and TM 24/7 (HR 0.49, 95% CrI 0.20 to 1.18); however, these results were statistically inconclusive. The results for TM 24/7 should be treated with caution because of the poor methodological quality of the only included study in this network. No favourable effect on mortality was observed with STS HM. Similar reductions were observed in all-cause hospitalisations for TM interventions, whereas STS interventions had no major effect. A sensitivity analysis, in which a study was excluded because it provided better-than-usual support to the control group, showed larger beneficial effects for most outcomes, particularly for TM during office hours. In the cost-effectiveness analyses, TM during office hours was the most cost-effective strategy with an estimated incremental cost-effectiveness ratio (ICER) of £11,873 per quality-adjusted life-year (QALY) compared with usual care, whereas STS HH had an ICER of £228,035 per QALY compared with TM during office hours. STS HM was dominated by usual care. Similar results were observed in scenario analyses performed using higher costs of usual care, higher costs of STS HH and lower costs of TM during office hours.

LIMITATIONS

The RM interventions included in the review were heterogeneous in terms of monitored parameters and HF selection criteria and lacked detail in the components of the RM care packages and usual care (e.g. communication protocols, routine staff visits and resources used). As a result, the economic model developed scenarios for different RM classifications and their costs were estimated using bottom-up costing methods. Although the users can decide which of these scenarios is most representative of their setting, uncertainties still remain about the assumptions made in the estimation of these costs. In addition, the model assumed that the effectiveness of the interventions was constant over time, irrespective of the duration of deployment, and that the intervention was equally effective in different age/severity groups.

CONCLUSION

Despite wide variation in usual care and RM strategies, cost-effectiveness analyses suggest that TM during office hours was an optimal strategy (in most costing scenarios). However, clarity was lacking among descriptions of the components of RM packages and usual care and there was a lack of robust estimation of costs. Further research is needed in these areas.

STUDY REGISTRATION

PROSPERO registration no. CRD42011001368.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.