Factors Associated with Resilience Among Older People Living with HIV.

Resilience, a measure of stress coping ability, may be important in helping older people (age 50+) living with HIV (PLWH) age successfully, but limited data exist regarding factors that contribute to resilience for this group. This study uses the Connor-Davidson Resilience Scale 2 (CD-RISC2) to assess resilience, based on a cross-sectional analysis of 1047 older PLWH. Bivariate linear regression models were used to identify predictor variables that had a relationship with resilience. Those variables were then included in a multivariable linear regression model, which was pared using backward selection. In the multivariable model, higher income and greater interpersonal support were associated with greater resilience, whereas depression and anxiety were associated with lower resilience. Relevant interventions that address these issues, such as increasing opportunities for social support and increasing screening for and treatment of depression and anxiety, are identified as potential pathways to increase resilience among older PLWH.

Utility and Impact of the Implementation of Same-Day, Self-administered Electronic Patient-Reported Outcomes Assessments in Routine HIV Care in two North American Clinics.

The PROgress study assessed the value and feasibility of implementing web-based patient-reported outcomes assessments (PROs) within routine HIV care at two North American outpatient clinics. People with HIV (PWH) completed PROs on a tablet computer in clinic before their routine care visit. Data collection included PROs from 1632 unique PWH, 596 chart reviews, 200 patient questionnaires, and 16 provider/staff questionnaires. During an initial setup phase involving 200 patients, PRO results were not delivered to providers; for all subsequent patients, providers received PRO results before the consultation. Chart review demonstrated that delivery of PRO results to providers improved patient-provider communication and increased the number of complex health and behavioral issues identified, recorded, and acted on, including suicidal ideation (88% with vs 38% without PRO feedback) and anxiety (54% with vs 24% without PRO feedback). In post-visit questionnaires, PWH (82%) and providers (82%) indicated that the PRO added value to the visit.

Relationship Between Polypharmacy and Quality of Life Among People in 24 Countries Living With HIV.

INTRODUCTION: People living with HIV (PLHIV) have greater risk of having multiple health conditions. We measured the relationship between increased medication and overall quality of life among PLHIV from 24 countries. METHODS: We analyzed data for 2,112 adult PLHIV on antiretroviral therapy (ART) in 24 countries who completed the 2019 Positive Perspectives survey. Polypharmacy was defined as taking 5 or more pills a day or currently taking medications for 5 or more conditions. Outcomes were self-rated overall health, treatment satisfaction, and self-reported virologic control. New treatment concerns were issues not prioritized at ART initiation but now deemed paramount. Data were analyzed with descriptive and multivariable statistics. RESULTS: Overall prevalence of polypharmacy was 42.1%. People reporting polypharmacy had significantly poorer health outcomes independent of existing comorbidities; their odds of treatment satisfaction, optimal overall health, and virologic control were lower by 27.0% (adjusted odds ratio [AOR] = 0.73; 95% CI, 0.59-0.91), 36.0% (AOR = 0.64; 95% CI, 0.53-0.78), and 46.0% (AOR = 0.54, 95% CI, 0.42-0.70), respectively, compared with those without polypharmacy (all P < .05). Most PLHIV (56.6%) were concerned about taking more medicines as they age, and 73.1% were interested in ARTs with fewer medicines. Top reasons for switching ART among those who had ever switched (n = 1,550) were to reduce severity and frequency of side effects (45.3%), number of pills (35.0%), or number of medicines (26.8%). People reporting polypharmacy had significantly higher odds of having new concerns relative to when they initiated ART, regarding risks of drug-drug interactions (AOR = 1.32; 95% CI, 1.02-1.71) and side effects (AOR = 1.31; 95% CI, 1.02-1.68). CONCLUSION: Polypharmacy was associated with poorer health-related outcomes among PLHIV. Many PLHIV expressed concerns about side effects of ART. Clinicians should carefully consider patient preferences, comorbidities, and drug profiles when prescribing ART.

PRO-Act: a healthcare provider workshop outlining the added value of implementing PROs in routine HIV practice.

Patient Reported Outcomes (PROs) are an evidenced way of adding value to routine clinical care. As a source of unique information on the effect of a medical condition and its treatment from the patients' perspective (Mercieca-Bebber et al. in Patient Relat Outcome Meas 9: 353-367, https://doi.org/10.2147/PROM.S156279 , 2018), PROs allow for an improved assessment in routine clinical care of symptoms, side effects, functional outcomes (physical, sexual, social, emotional, cognitive functioning), and health-related quality of life (HRQoL). By helping to align healthcare providers' interventions with what matters most to the patient, PROs contribute to the individualized choice of Anti-Retroviral Therapy (Carfora et al. in PLoS ONE 17(4): e0267030, https://doi.org/10.1371/journal.pone.0267030 , 2022) as a paramount component of tailored and person-centred care management, in routine clinical practice. This article outlines a practical framework and process tested in Portugal to raise awareness of PROs' added value, and to help guide first steps in the implementation and seamless integration of PROs, in routine HIV care.

Waitlist-controlled trial of an online intervention to address mental health among older people living with HIV.

Background: Older people living with HIV (PLWH) often experience elevated levels of depression, anxiety, and loneliness.Methods: This waitlist-controlled trial examined the effectiveness of online audio mindfulness lessons in impacting these feelings among older PLWH.Results: Among 214 participants, the mean (SD) age was 60.4 (5.9) years, 89% were male, and 69% were white. After 25 days, the intervention group showed significant improvements versus the waitlist control group in symptoms of depression (20.3% improvement, p < .01) and symptoms of anxiety (22.4% improvement, p = .03), but not in loneliness as measured by a Daily Diary (12.9% improvement, p = .07) or the 3-Item Loneliness Scale (4.8% improvement, p = .27). Secondary analyses among participants with elevated baseline symptoms of depression showed a 26.3% improvement (p < .01), with a moderate effect size (Hedge's g = 0.69). Similarly, those with elevated baseline symptoms of anxiety showed a 25.6% improvement (p < .01), a moderate effect size (g = 0.54), while those with moderate or severely elevated loneliness showed an 18.9% improvement in daily loneliness (p < .01), a moderate effect size (g = 0.55).Conclusion: This waitlist-controlled trial is the first to show that a series of brief, online audio mindfulness lessons improves mental health outcomes among older PLWH. For many patients, this intervention may offer relief that is both accessible and affordable.

Implementation of a Nurse-Delivered Cognitive Behavioral Therapy for Adherence and Depression of People Living with HIV in Korea.

BACKGROUND: Cognitive behavioral therapy for adherence and depression (CBT-AD) performed by clinical psychologists is an effective treatment for improving the depression in people living with HIV (PLWH). However, because access to clinical psychologists is limited in most clinics, CBT-AD is rarely performed for PLWH in Korea. This pilot study evaluates whether CBT-AD can be effectively performed by a nurse trained and supervised by a clinical psychologist, with a view to the wider provision of CBT-AD. MATERIALS AND METHODS: One clinical psychologist developed manuals, educated and supervised one nurse. PLWH with depression or adherence to self-reported antiretroviral therapy <90% were enrolled, and CBT-AD was conducted once weekly for 12 sessions. PLWH were assessed for adherence by visual analog scale, Beck depression inventory (BDI) for depression, PozQoL for quality of life, and Berger's 40-item stigma scale for stigma at baseline, after the 6th, 12th session, at 4-, and 8-months after CBT-AD. Acceptability for PLWH and feasibility for providers were evaluated through surveys. RESULTS: Five male PLWH have completed the study protocols (mean age 29.2 years). All study participants showed improving depression (mean BDI at baseline 33.0 ± 7.0, and after the 12th session 13.4 ± 3.5), and the effect was maintained at the 8-month follow-up (BDI 15.4 ± 6.4). Quality of life showed a tendency to improve (mean PozQoL at baseline 28.0 ± 7.7, after 12th session 36.8 ± 4.4, and at the 8-month follow-up 38.2 ± 7.9), but stigma did not show clear improvement (Berger's 40-item stigma scale at baseline 121.0 ± 3.9, after 12th session 107.6 ± 8.8. and at the 8-month follow-up 107.6 ± 5.0). All study participants received great help from CBT-AD and expressed their desire to continue. All providers agreed that nurse-delivered CBT-AD could be implemented in routine clinical practice. CONCLUSION: Our findings suggest that a nurse-delivered CBT-AD could be feasible and acceptable for PLWH through structured interventions. It has been shown to have the potential to help PLWH, especially for their depression and quality of life. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03823261.

Feasibility of implementing a same-day electronic screening tool for clinical assessment to measure patient-reported outcomes for eliciting actionable information on adherence to HIV medication and related factors in a busy Canadian urban HIV clinic.

BACKGROUND: An optimal adherence to antiretroviral therapy (ART) is fundamental for suppression of HIV viral load and favourable treatment outcomes. Patient-reported outcomes (PROs) are effective tools for improving patient-provider communication and focusing providers' awareness on current health problems. The objectives of this analysis were (1) to determine the feasibility of implementing an electronic screening tool to measure PROs in a Canadian HIV clinic to obtain information on ART adherence and related factors and (2) to determine the factors related to sub-optimal adherence. METHODS: This implementation research with a convenience sample of 600 people living with HIV (PLWH) was conducted in a busy, academic, urban HIV clinic in Toronto, Canada. PLWH were approached to participate in PRO assessments just prior to their in-clinic appointments, including health-related domains such as mental health, housing, nutrition, financial stress and medication adherence, and responses were summarized on a single sheet available for providers to review. Feasibility of implementing PROs was assessed by quantifying response rate, completion rate, time taken and participation rate. Medication adherence was elicited by self-report of the percentage of prescribed HIV medications taken in the last month. Unadjusted and adjusted odds ratios were estimated from logistic regression models to identify factors associated with adherence of <95%. RESULTS: Of the 748 PLWH invited to participate, 692 (participation rate: 92.5%) completed the PRO assessments as standard of care in clinic. Of these, 600 consented to the use of their PRO results for research and were included in this analysis. The average response rate to the ART-related questions was 96.8% and mean completion rate was 95.5%. The median time taken to complete the assessment was 12.0 (IQR = 8.4-17.3) min, adjusted 8.7 (IQR = 7.2-10.8) min. 445 (74.9%) of participants were male, and 153 (26.2%) reported dissatisfaction with ART. 105 (19.7%) of the PLWH reported ART adherence of <95%. Multivariable logistic regression identified the following risk factors for sub-optimal adherence: dissatisfaction with ART (OR = 2.30, 95% CI 1.38-3.83), not having a family doctor or not visiting a family doctor in last year (OR = 1.69, 95% CI 1.02-2.79). CONCLUSION: Collecting self-reported health information from PLWH through PROs in a busy urban clinic was feasible and can provide relevant information to healthcare providers on issues related to adherence. This has a potential to help in individualizing ambulatory care.

Risk Factors for Suboptimal Adherence Identified by Patient-Reported Outcomes Assessments in Routine HIV Care at 2 North American Clinics.

Purpose: Use of patient-reported outcomes assessments (PROs) can improve patient-provider communication and focus provider attention on current health issues. This analysis examines the association between suboptimal antiretroviral therapy (ART) adherence and factors obtained through PROs among people with HIV (PWH) at 2 North American outpatient clinics. Patients and Methods: Immediately before a clinic visit, PWH completed self-administered PROs. Unadjusted and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated from logistic regression models to identify sociodemographic and health-related factors (satisfaction with ART, difficulty meeting housing costs, depression, intimate partner violence, risk of malnutrition, smoking status, alcohol use, and substance use) associated with suboptimal adherence (defined as self-reporting <95% or <80% adherence). Multiple imputation was performed to account for missing data in the multivariate analyses. Results: Of 1632 PWH, 1239 (76%) responded to the adherence assessment; of these, 268 (22%) and 106 (9%) reported <95% and <80% adherence, respectively. Of 1580 PWH who responded, 354 (22%) were dissatisfied with their HIV medication. Of responding PWH, 19% reported moderate-to-severe depression, 23% indicated they were at risk of malnutrition, 34% were current smokers, and 62% reported substance use in the past 3 months. Dissatisfaction with ART was significantly associated with <95% and <80% adherence in the unadjusted analysis (unadjusted OR [95% CI], 3.38 [2.51-4.56] and 4.26 [2.82-6.42], respectively) and adjusted analysis (adjusted OR [95% CI], 2.76 [1.91-4.00] and 3.28 [1.95-5.52], respectively); significance remained after multiple imputation. In adjusted analyses, no risk of malnutrition was significantly associated with reduced odds of <95% adherence after multiple imputation (adjusted OR [95% CI], 0.714 [0.511-0.997]); no other factors were associated with <95% or <80% adherence. Conclusion: These results suggest that implementation of PROs evaluating treatment satisfaction may provide value to adherence management in routine HIV care.

Do ART and Chemsex Drugs Get Along? Potential Drug-Drug Interactions in a Cohort of People Living with HIV Who Engaged in Chemsex: A Retrospective Observational Study.

INTRODUCTION: People living with HIV (PLWH) who engaged in chemsex are at risk of potential drug-drug interactions (pDDIs) with recreational drugs. This study aimed to characterize pDDIs between antiretroviral treatment (ART) and chemsex drugs and evaluate their association with unscheduled relevant hospital consultations. METHODS: We conducted a single-center, retrospective, observational study in a series of gay, bisexual, and other men who have sex with men (gbMSM) living with HIV who engaged in chemsex and who attended a tertiary hospital in Barcelona, Spain, from February 2018 through August 2019. Associations between all recorded pDDIs and relevant unscheduled consultations were estimated using the incidence rate (IR) per 100 person-years of those events compared between patients with no pDDI (green flag) or moderate severity pDDI (orange flag) with patients with high severity pDDI (red flag) using the incidence rate ratio (IRR). RESULTS: Among 172 PLWH engaged in chemsex, 249 ART regimens were prescribed: 44% based on integrase inhibitors, 30% on boosted ART, and 26% based on non-nucleoside reverse transcriptase inhibitors. The substances and recreational drugs most frequently used were erectile dysfunction agents (83%), methamphetamine (79%), GHB (77%), and alkyl nitrites (71%). Polydrug use was reported in 52%. We observed 2048 pDDIs. Of these, 23% were orange flag pDDIs; 88% related to boosted ARTs. The IR of the 285 unscheduled relevant episodes in patients with orange flag pDDIs was 64.67 (95% CI 40.07-89.28). The IRR of green flag pDDIs was 1.05 (95% CI 0.60-1.8; p = 0.876). CONCLUSION: One in four pDDIs were of moderate severity but no significant increase in the incidence of unscheduled relevant consultations was observed. A high number of unscheduled consultations, predominantly for psychiatric events and intoxication, were observed. Beyond using non-boosted ART to minimize pDDIs, other factors related to the practice of chemsex must be addressed, in order to offer a better approach.

Improving the continuum of care monitoring in Brazilian HIV healthcare services: An implementation science approach.

OBJECTIVE: To evaluate the impact of an intervention improving the continuum of care monitoring (CCM) within HIV public healthcare services in São Paulo, Brazil, and implementing a clinical monitoring system. This system identified three patient groups prioritized for additional care engagement: (1) individuals diagnosed with HIV, but not receiving treatment (the treatment gap group); (2) individuals receiving treatment for >6 months with a detectable viral load (the virologic failure group); and (3) patients lost to follow-up (LTFU). METHODS: The implementation strategies included three training sessions, covering system logistics, case discussions, and development of maintenance goals. These strategies were conducted within 30 HIV public healthcare services (May 2019 to April 2020). After each training session, professionals shared their experiences with CCM at regional meetings. Before and after the intervention, providers were invited to answer 23 items from the normalization process theory questionnaire (online) to understand contextual factors. The mean item scores were compared using the Mann-Whitney U test. The RE-AIM implementation science framework (evaluating reach, effectiveness, adoption, implementation, and maintenance) was used to evaluate the integration of the CCM. RESULTS: In the study, 47 (19.3%) of 243 patients with a treatment gap initiated treatment, 456 (49.1%) of 928 patients with virologic failure achieved suppression, and 700 of 1552 (45.1%) LTFU patients restarted treatment. Strategies for the search and reengagement of patients were developed and shared. Providers recognized the positive effects of CCM on their work and how it modified existing activities (3.7 vs. 4.4, p<0.0001, and 3.9 vs. 4.1, p<0.05); 27 (90%) centers developed plans to sustain routine CCM. CONCLUSION: Implementing CCM helped identify patients requiring more intensive attention. This intervention led to changes in providers' perceptions of CCM and care and management processes, which increased the number of patients engaged across the care continuum and improved outcomes.

Network generation enhances interpretation of proteomic data from induced apoptosis.

Thirteen proteins (identified with 2-D gels and MALDI-TOF MS) are significantly altered during staurosporine-induced apoptosis in SH-SY5Y cells. To gain further insight into the integrated cellular response to apoptosis, we have investigated whether a network can be generated of direct and indirect interactions between these 13 proteins. A network that contains 12 out of the 13 proteins was generated using Ingenuity Pathway Analysis (IPA) and this network is dominated (89%) by direct protein-protein interactions. This network scored 34 with IPA. Bootstrapping 1000 random lists of 13 proteins suggested that the frequency of this score occurring by chance was 1 in 500. We examined whether subsets of proteins such as HSPs, which were elevated after staurosporine, had a disproportionate impact on the network generated. There was no evidence that any subset of 8 from the 13 proteins contributed disproportionately to the network. Network generation, using IPA, identified common features (such as endoplasmic reticular stress protein interactions) in apoptotic studies from different laboratories. The generation of protein interaction networks clearly enhances the interpretation of proteomic data, but only when interpreted cautiously, particularly in respect of statistical analyses.

Why are eligible patients not prescribed aspirin in primary care? A qualitative study indicating measures for improvement.

BACKGROUND: Despite evidence-based guidelines, aspirin prescribing for the secondary prevention of stroke is sub-optimal. Little is known about why general practitioners do not prescribe aspirin to indicated patients. We sought to identify and describe factors that lead general practitioners (GPs) not to prescribe aspirin to eligible stroke patients. This was the first stage of a study exploring the need for and means of improving levels of appropriate aspirin prescribing. METHOD: Qualitative interviews with 15 GPs in the West Midlands. RESULTS: Initially, many GPs did not regard their prescribing as difficult or sub-optimal. However on reflection, they gave several reasons that lead to them not prescribing aspirin for eligible patients or being uncertain. These include: difficulties in applying generic guidelines to individuals presenting in consultations, patient resistance to taking aspirin, the prioritisation of other issues in a time constrained consultation and problems in reviewing the medication of existing stroke patients. CONCLUSION: In order to improve levels of appropriate aspirin prescribing, the nature and presentation risk information available to GPs and patients must be improved. GPs need support in assessing the risks and benefits of prescribing for patients with combinations of complicating risk factors, while means of facilitating improved GP-patient dialogue are required to help address patient uncertainty. A decision analysis based support system is one option. Decision analysis could synthesise current evidence and identify risk data for a range of patient profiles commonly presenting in primary care. These data could then be incorporated into a user-friendly computerised decision support system to help facilitate improved GP-patient communication. Measures of optimum prescribing based upon aggregated prescribing data must be interpreted with caution. It is not possible to assess whether low levels of prescribing reflect appropriate or inappropriate use of aspirin in specific patients where concordance between the GP and the patient is practised.

Barriers to the adoption of computerised decision support systems in general practice consultations: a qualitative study of GPs' perspectives.

INTRODUCTION: Computerised decision support systems are increasingly important in primary care for the practice of evidence-based medicine and the development of shared GP-patient decision making. However, despite their emergence, such systems have not been entirely embraced by GPs. There is little qualitative research exploring practical barriers to the adoption of decision support systems in this setting. METHOD: Qualitative interviews with 15 GPs in the West Midlands. RESULTS: Several practical barriers were identified to the use of computerised support systems in primary care consultations. These included limitations of practitioners' IT skills, problems for GPs in understanding the risk output of systems and GP concerns about communicating risk sufficiently well to patients. Concerns over the time implications of using a system in a consultation was also identified as a barrier. CONCLUSION: Designers of decision support systems for use in primary care consultations must account for the practical needs of users when developing computerised support systems. Systems must be acceptable to the format of a consultation, include definitions of what output means, and help facilitate dialogue between the GP and the patient.

The development and evaluation of a computerised decision support system for primary care based upon 'patient profile decision analysis'.

OBJECTIVE: To develop and evaluate in primary care a computerised decision support system for the management of stroke patients based upon 'patient profile decision analysis'. DESIGN: The decision support system incorporated the findings of 960 Markov models examining the decision to prescribe aspirin in the secondary prevention of stroke. The models reflected each combination of nine risk factors that determined a patient's profile. The evaluation comprised a qualitative interview and a questionnaire administered before and after the general practitioners (GPs) were given access to the support system. SETTING: Primary care. PARTICIPANTS: 15 GPs from the West Midlands. MAIN OUTCOME MEASURES: Decision certainty scoring of hypothetical patient vignettes. Qualitative perceptions of the applicability and acceptability of the system for primary care. RESULTS: After using the system, GPs were more certain of their decision making and made decisions more in line with national guidelines. Quantitative results further suggested that the system made decision making easier, improved feelings of being supported, improved the quality of decision making and increased satisfaction. Qualitative themes included that GPs thought the system could clarify their own decision making and improve GP-patient dialogue. CONCLUSIONS: The feasibility of individualised decision analysis for general practice has been questioned. Patient profile decision analysis, however, may be a valuable means of harnessing some of the advantages of the methodology to produce more patient-specific guidelines for primary care.

Determining patient characteristics for decision analysis support systems using anonymized electronic patient records.

While decision analysis has the potential to improve treatment decisions, the quality of patient specific data has hindered its development. Experience with the General Practice Research Database (GPRD) indicated the possibility of generating such data. The example developed concerns the probability of recurrent stroke and the risks and benefits of treatment with aspirin. Eight criteria were systematically applied to identify suitable patients from the 664,241 cohort of patients in the West Midlands GPRD. The risk of recurrent stroke was estimated using survival analysis, yielding multivariate hazard ratios for 960 patient profiles. These were used to populate a decision analysis model. The study highlights how decision analysis can introduce evidence-based information into the consultation. Data can be transformed into information for the increasingly complex world of general practice. This can clarify the risks and benefits of prescribing, assist GP-patient dialogue and promote shared decision-making.

The utility of functional interaction and cluster analysis in CNS proteomics.

Proteomic studies offer enormous potential for gaining insight into cellular dynamics and disease processes. An immediate challenge for enhancing the utility of proteomics in translational research lies in methods of handling and interpreting the large datasets generated. Publications rarely extend beyond lists of proteins, putatively altered derived from basic statistics. Here we describe two additional distinct approaches (with particular strengths and limitations) that will enhance the analysis of proteomic datasets. Arithmetic and functional cluster analyses have been performed on proteins found differentially regulated in human glioma. These two approaches highlight (i) subgroups of proteins that may be co-regulated and play a role in glioma pathophysiology, and (ii) functional protein interactions that may improve comprehension of the biological mechanisms involved. A coherent proteomic strategy which involves both arithmetic and functional clustering, (together with careful consideration of conceptual limitations), is imperative for quantitative proteomics to deliver and advance the biological understanding of disease of the CNS. A strategy which combines arithmetic analysis and bioinformatics of protein-protein interactions is both generally applicable and will facilitate the interpretation of proteomic data.

Patients' experiences of a community pharmacy-led medicines management service.

Medicines management services provided by community pharmacists have been proposed as one means to ensure that patients receive all the medicines they may benefit from in the English National Health Service. These services may also offer ways of addressing the historic under-utilization of community pharmacists' clinical skills and expertise. Medicines management services differ significantly from the dispensing and medicines sales roles traditionally associated with community pharmacy, particularly in relation to the provision for pharmacists to make recommendations to both patients and doctors about pharmacological treatment and lifestyle management. This paper describes patients' experiences of a medicines management service provided by community pharmacists for people with coronary heart disease, delivered in England. It draws on findings from semistructured, face-to-face interviews with 49 patients recruited from pilot sites delivering the service. Findings suggest that although patients cautiously welcomed the opportunity to consult with a pharmacist about their medicines, they had reservations about them making recommendations about treatment, and many still regarded the doctor as the health professional 'in charge' of their medicines. The implications of these findings are discussed in light of the developing sociological literature on pharmacy and medicines usage.

Apoptosis induced by staurosporine alters chaperone and endoplasmic reticulum proteins: Identification by quantitative proteomics.

Apoptosis contributes to cell death after cerebral ischaemia. A quantitative proteomics approach has been employed to define alterations in protein levels in apoptosis induced with staurosporine (STS). Human neuroblastoma derived SH-SY5Y cells were treated with STS (500 nM for 6 h) to induce apoptosis. Quantitative 2-DE was used to determine the changing protein levels with MALDI-TOF MS identification of proteins. Of the 154 proteins analysed, 13 proteins were significantly altered as a result of the apoptotic stimulus; ten of the proteins showed an increase in level with STS and were identified as heat shock cognate 71 (Hsc71), two isoforms of heat shock protein 70 (Hsp70), glucose regulated protein 78 (GRP78), F-actin capping protein, stress-induced phosphoprotein 1, chromatin assembly factor 1 (CAF-1), protein disulphide isomerase A3 (PDI A3) precursor, transitional ER ATPase and actin interacting protein 1 (AIP 1). Three proteins which displayed significant decrease in levels with STS were identified as tubulin, vimentin and glucose regulated protein 94 (GRP94). The functional roles and subcellular locations of these proteins collectively indicate that STS-induced apoptosis provokes induces an unfolded protein response involving molecular chaperones, cochaperones and structural proteins indicative of ER stress.

Differential proteomics analysis of synaptic proteins identifies potential cellular targets and protein mediators of synaptic neuroprotection conferred by the slow Wallerian degeneration (Wlds) gene.

Non-somatic synaptic and axonal compartments of neurons are primary pathological targets in many neurodegenerative conditions, ranging from Alzheimer disease through to motor neuron disease. Axons and synapses are protected from degeneration by the slow Wallerian degeneration (Wld(s)) gene. Significantly the molecular mechanisms through which this spontaneous genetic mutation delays degeneration remain controversial, and the downstream protein targets of Wld(s) resident in non-somatic compartments remain unknown. In this study we used differential proteomics analysis to identify proteins whose expression levels were significantly altered in isolated synaptic preparations from the striatum of Wld(s) mice. Eight of the 16 proteins we identified as having modified expression levels in Wld(s) synapses are known regulators of mitochondrial stability and degeneration (including VDAC1, Aralar1, and mitofilin). Subsequent analyses demonstrated that other key mitochondrial proteins, not identified in our initial screen, are also modified in Wld(s) synapses. Of the non-mitochondrial proteins identified, several have been implicated in neurodegenerative diseases where synapses and axons are primary pathological targets (including DRP-2 and Rab GDP dissociation inhibitor beta). In addition, we show that downstream protein changes can be identified in pathways corresponding to both Ube4b (including UBE1) and Nmnat1 (including VDAC1 and Aralar1) components of the chimeric Wld(s) gene, suggesting that full-length Wld(s) protein is required to elicit maximal changes in synaptic proteins. We conclude that altered mitochondrial responses to degenerative stimuli are likely to play an important role in the neuroprotective Wld(s) phenotype and that targeting proteins identified in the current study may lead to novel therapies for the treatment of neurodegenerative diseases in humans.

Metabolism of trans, trans-muconaldehyde, a cytotoxic metabolite of benzene, in mouse liver by alcohol dehydrogenase Adh1 and aldehyde reductase AKR1A4.

The reductive metabolism of trans, trans-muconaldehyde, a cytotoxic metabolite of benzene, was studied in mouse liver. Using an HPLC-based stopped assay, the primary reduced metabolite was identified as 6-hydroxy-trans, trans-2,4-hexadienal (OH/CHO) and the secondary metabolite as 1,6-dihydroxy-trans, trans-2,4-hexadiene (OH/OH). The main enzymes responsible for the highest levels of reductase activity towards trans, trans-muconaldehyde were purified from mouse liver soluble fraction first by Q-sepharose chromatography followed by either blue or red dye affinity chromatography. In mouse liver, trans, trans-muconaldehyde is predominantly reduced by an NADH-dependent enzyme, which was identified as alcohol dehydrogenase (Adh1). Kinetic constants obtained for trans, trans-muconaldehyde with the native Adh1 enzyme showed a Vmax of 2141+/-500 nmol/min/mg and a Km of 11+/-4 microM. This enzyme was inhibited by pyrazole with a KI of 3.1+/-0.57 microM. Other fractions were found to contain muconaldehyde reductase activity independent of Adh1, and one enzyme was identified as the NADPH-dependent aldehyde reductase AKR1A4. This showed a Vmax of 115 nmol/min/mg and a Km of 15+/-2 microM and was not inhibited by pyrazole.