TMEM164 is an acyltransferase that forms ferroptotic C20:4 ether phospholipids.

Ferroptosis is an iron-dependent form of cell death driven by oxidation of polyunsaturated fatty acid (PUFA) phospholipids. Large-scale genetic screens have uncovered a specialized role for PUFA ether phospholipids (ePLs) in promoting ferroptosis. Understanding of the enzymes involved in PUFA-ePL production, however, remains incomplete. Here we show, using a combination of pathway mining of genetic dependency maps, AlphaFold-guided structure predictions and targeted lipidomics, that the uncharacterized transmembrane protein TMEM164-the genetic ablation of which has been shown to protect cells from ferroptosis-is a cysteine active center enzyme that selectively transfers C20:4 acyl chains from phosphatidylcholine to lyso-ePLs to produce PUFA ePLs. Genetic deletion of TMEM164 across a set of ferroptosis-sensitive cancer cell lines caused selective reductions in C20:4 ePLs with minimal effects on C20:4 diacyl PLs, and this lipid profile produced a variable range of protection from ferroptosis, supportive of an important but contextualized role for C20:4 ePLs in this form of cell death.

A programme evaluation of 'First Steps': A peer-conceived, developed and led self-management intervention for people after a Parkinson's diagnosis.

OBJECTIVE: A diagnosis of Parkinson's often leads to uncertainty about the future and loss of perceived control. Peer support may offer a means to address these concerns and promote self-management. DESIGN: A programme evaluation of the feasibility and potential effects of 'First Steps', utilising a pragmatic step wedge approach. Comparing First Steps (intervention) to (control) conditions.Setting: In the community at four sites in southern England.Participants: Newly diagnosed (≤ 12months) people with Parkinson's.Intervention: First Steps was a 2-day peer-conceived, developed and led intervention to support self-management.Main measures: At 0, 12 and 24 weeks anxiety and depression (Hospital, Anxiety and Depression Scale, HADS), daily functioning (World Health Organisation Disability Assessment Schedule, WHODAS), physical activity, quality of life (EQ5D), carer strain and service utilisation were assessed. RESULTS: Between February 2018 and July 2019, 36 participants were enrolled into intervention and 21 to control conditions, all were included in statistical analysis. Lost to follow up was n = 1 (intervention) and n = 1 adverse event was reported (control, unrelated). Of the 36 allocated to the intervention n = 22 participants completed both days of First Steps during the study period. Completion of outcome measures was >95% at 24 weeks. Small effects favouring the intervention were found for HADS (odds ratio (OR) = 2.06, 95% confidence interval (CI) 0.24:17.84), Carer Strain Index (OR = 2.22, 95% CI 0.5:9.76) and vigorous (d = 0.42, 95% CI -0.12:0.97) and total physical activity (d = 0.41, 95% CI -0.13:0.95). EQ5D, WHOSDAS and service utilisation, was similar between groups. CONCLUSIONS: First Steps was feasible and safe and we found potential to benefit physical activity, mental health and carer strain. Further research with longer-term follow up is warranted.

Phospholipase Cγ2 regulates endocannabinoid and eicosanoid networks in innate immune cells.

Human genetic studies have pointed to a prominent role for innate immunity and lipid pathways in immunological and neurodegenerative disorders. Our understanding of the composition and function of immunomodulatory lipid networks in innate immune cells, however, remains incomplete. Here, we show that phospholipase Cγ2 (PLCγ2 or PLCG2)-mutations in which are associated with autoinflammatory disorders and Alzheimer's disease-serves as a principal source of diacylglycerol (DAG) pools that are converted into a cascade of bioactive endocannabinoid and eicosanoid lipids by DAG lipase (DAGL) and monoacylglycerol lipase (MGLL) enzymes in innate immune cells. We show that this lipid network is tonically stimulated by disease-relevant human mutations in PLCγ2, as well as Fc receptor activation in primary human and mouse macrophages. Genetic disruption of PLCγ2 in mouse microglia suppressed DAGL/MGLL-mediated endocannabinoid-eicosanoid cross-talk and also caused widespread transcriptional and proteomic changes, including the reorganization of immune-relevant lipid pathways reflected in reductions in DAGLB and elevations in PLA2G4A. Despite these changes, Plcg2-/- mice showed generally normal proinflammatory cytokine and chemokine responses to lipopolysaccharide treatment, instead displaying a more restricted deficit in microglial activation that included impairments in prostaglandin production and CD68 expression. Our findings enhance the understanding of PLCγ2 function in innate immune cells, delineating a role in cross-talk with endocannabinoid/eicosanoid pathways and modulation of subsets of cellular responses to inflammatory stimuli.

ABHD12 and LPCAT3 Interplay Regulates a Lyso-phosphatidylserine-C20:4 Phosphatidylserine Lipid Network Implicated in Neurological Disease.

PHARC (polyneuropathy, hearing loss, cerebellar ataxia, retinitis pigmentosa, and cataract) is a human neurological disorder caused by deleterious mutations in the ABHD12 gene, which encodes an integral membrane lyso-phosphatidylserine (lyso-PS) lipase. Pharmacological or genetic disruption of ABHD12 leads to higher levels of lyso-PS lipids in human cells and the central nervous system (CNS) of mice. ABHD12 loss also causes rapid rewiring of PS content, resulting in selective increases in the level of arachidonoyl (C20:4) PS and decreases in the levels of other PS species. The biochemical basis for ABHD12-dependent PS remodeling and its pathophysiological significance remain unknown. Here, we show that genetic deletion of the lysophospholipid acyltransferase LPCAT3 blocks accumulation of brain C20:4 PS in mice lacking ABHD12 and concurrently produces hyper-increases in the level of lyso-PS in these animals. These lipid changes correlate with exacerbated auditory dysfunction and brain microgliosis in mice lacking both ABHD12 and LPCAT3. Taken together, our findings reveal that ABHD12 and LPCAT3 coordinately regulate lyso-PS and C20:4 PS content in the CNS and point to lyso-PS lipids as the likely bioactive metabolites contributing to PHARC-related neuropathologies.

Selective blockade of the lyso-PS lipase ABHD12 stimulates immune responses in vivo.

ABHD12 metabolizes bioactive lysophospholipids, including lysophosphatidylserine (lyso-PS). Deleterious mutations in human ABHD12 cause the neurological disease PHARC, and ABHD12-/- mice display PHARC-like phenotypes, including hearing loss, along with elevated brain lyso-PS and features of stimulated innate immune cell function. Here, we develop a selective and in vivo-active inhibitor of ABHD12 termed DO264 and show that this compound elevates lyso-PS in mouse brain and primary human macrophages. Unlike ABHD12-/- mice, adult mice treated with DO264 exhibited minimal perturbations in auditory function. On the other hand, both DO264-treated and ABHD12-/- mice displayed heightened immunological responses to lymphocytic choriomeningitis virus (LCMV) clone 13 infection that manifested as severe lung pathology with elevated proinflammatory chemokines. These results reveal similarities and differences in the phenotypic impact of pharmacological versus genetic blockade of ABHD12 and point to a key role for this enzyme in regulating immunostimulatory lipid pathways in vivo.

Monoacylglycerol Lipase Inhibition in Human and Rodent Systems Supports Clinical Evaluation of Endocannabinoid Modulators.

Monoacylglycerol lipase (MGLL) is the primary degradative enzyme for the endocannabinoid 2-arachidonoylglycerol (2-AG). The first MGLL inhibitors have recently entered clinical development for the treatment of neurologic disorders. To support this clinical path, we report the pharmacological characterization of the highly potent and selective MGLL inhibitor ABD-1970 [1,1,1,3,3,3-hexafluoropropan-2-yl 4-(2-(8-oxa-3-azabicyclo[3.2.1]octan-3-yl)-4-chlorobenzyl)piperazine-1-carboxylate]. We used ABD-1970 to confirm the role of MGLL in human systems and to define the relationship between MGLL target engagement, brain 2-AG concentrations, and efficacy. Because MGLL contributes to arachidonic acid metabolism in a subset of rodent tissues, we further used ABD-1970 to evaluate whether selective MGLL inhibition would affect prostanoid production in several human assays known to be sensitive to cyclooxygenase inhibitors. ABD-1970 robustly elevated brain 2-AG content and displayed antinociceptive and antipruritic activity in a battery of rodent models (ED50 values of 1-2 mg/kg). The antinociceptive effects of ABD-1970 were potentiated when combined with analgesic standards of care and occurred without overt cannabimimetic effects. ABD-1970 also blocked 2-AG hydrolysis in human brain tissue and elevated 2-AG content in human blood without affecting stimulated prostanoid production. These findings support the clinical development of MGLL inhibitors as a differentiated mechanism to treat pain and other neurologic disorders.

Toward an Emerging Role for Motivational Interviewing in Primary Care.

PURPOSE OF REVIEW: Implementing Motivational Interviewing (MI) in primary care settings has been problematic due in part to persistent gaps in knowledge. Examples include poor understanding of how to effectively train persons to conduct MI, or of which aspects of MI-related communication are associated with better outcomes for patients. This review describes how recent research findings addressing the knowledge gaps support a growing role for MI in primary care. RECENT FINDINGS: Two trials of MI training combined classroom time with ongoing coaching and feedback, resulting in enhanced MI ability relative to a control arm where PCPs received minimal or no MI training. A third MI training trial excluded coaching and feedback, failing to increase use of MI. Adding to a growing list of behavioral health-related problems for which MI training has shown some effectiveness, a trial of training PCPs to use MI with depressed patients was associated with significantly improved depressive symptoms. Moreover, aspects of the PCPs' MI-related language and patients' arguments for positive behavior changes, "change talk," appeared to explain the positive effects of MI training on depression outcome. MI-training approaches have improved such that PCPs and possibly other clinic staff may want to consider MI training as a way to more effectively support their patients as they address behavioral health-related problems (e.g., tobacco use). MI training should focus on eliciting "change talk" from patients. Researchers and funding agencies might collaborate to continue closing knowledge gaps in the MI literature.

Psychological Attributes of Ultramarathoners.

INTRODUCTION: As the popularity of ultramarathon participation increases, there still exists a lack of understanding of the unique psychological characteristics of ultramarathon runners. The current study sought to investigate some of the psychological and behavioral factors that are involved in ultramarathon running. METHODS: We obtained information from participants of the Bear Chase Trail Race via an online survey. This race is a single-day, multidistance race consisting of a 10 k, half marathon, 50 k, 50 mi, and 100 k run in Lakewood, Colorado, at a base altitude of 1680 m with total altitude in climbs ranging from 663 to 2591 m. We correlated information from the Exercise Addiction Inventory and the Patient Health Questionnaire-2 and demographic information with race finish times. RESULTS: Out of 200 runners who started the race, 98 (48%) completed the survey. Over half of the runners were men (61.2%), and the average age was 39.0 years (SD±8.9; range 21-64 years). A number of respondents (20%) screened positive for exercise addiction concerns. Approximately 20% of our sample screened positive for depressive symptoms (Patient Health Questionnaire-2 score >3). The majority of participants reported receiving strong social support from current partners with regard to their ultramarathon running training time and goals. CONCLUSIONS: Although only a screening, the number of positive screens on the Exercise Addiction Inventory suggests use of screening measures with an ultramarathon running population. Athletes with positive screening tests should be fully evaluated for depression and exercise addiction because this would enable appropriate athlete support and treatment referral.

Lost employment potential and supporting people with Parkinson's to stay in work: insights from a Pan European cross-sectional survey.

PURPOSE: To explore, in a European cohort of people living with Parkinson's (PD), issues affecting employment and economic consequences, considering age at diagnosis. MATERIALS AND METHODS: A cross-sectional survey (European convenience sample). Inclusion criteria were ≥18 years, a PD diagnosis and in work when diagnosed. Data were collected online on demographics, employment status, occupation, and perceived health. For those no longer in paid work, time from diagnosis until loss of employment, reasons for leaving and enablers to stay in work were ascertained. RESULTS: Between April and November 2019, n = 692 enrolled and n = 560 were eligible. Those who had lost paid work (n = 190, 34%) reported worse fatigue, sleep, and general health than those still in work (p < 0.05). Average annual income reduced from €26973.48 ± 12013.22 (year-1) to €14843.85 ± 16969.84 (year-10). Post-diagnosis lost employment potential was 20.1 (95% confidence interval (CI): 16.6-23.6) years at career establishment, 9.8 (95%CI: 8.9-10.7) years at mid working and 1.2 (95%CI: 0.6-1.6) years for those nearing retirement age. A greater proportion of individuals at career establishment age reported dexterity, eating, sleep, fatigue, and anxiety as factors for leaving work (p < 0.05). CONCLUSIONS: This study confirms lost productivity after a PD diagnosis, especially in those with many years of potential employment ahead. The study also identified potential targets for interventions. Clinical trial registration: Clincaltrials.gov (NCT03905954).Implications for rehabilitationPeople with Parkinson's diagnosed at career establishment or at mid working age risk losing many years of potential employment.Most people with Parkinson's do not receive early intervention to support self-management of problems identified with leaving work early, such as fatigue.Adaptations to the work environment and more flexible working patterns were identified factors that may help people remain in work.

Colorado Family Physicians and Medical Marijuana: Has Recreational Marijuana Changed Physician Attitudes and Behaviors?

INTRODUCTION: Medical marijuana is permitted in 36 states; 15 states allow recreational marijuana use. Previous surveys showed that family physicians were concerned about the physical and mental health effects of medical marijuana use, but the impact of recreational marijuana legalization and liberalization of marijuana laws on physician attitudes is unknown. METHODS: A survey was distributed to 1582 members of the Colorado Academy of Family Physicians' listserv, with items on individual and practice characteristics and experience with and attitudes toward medical marijuana. The results of this survey were compared with that of a nearly identical survey conducted with the same group in 2011. RESULTS: The proportion of family physician respondents in Colorado recommending medical marijuana to patients was the same in 2020 as in 2011 at 31%; 53% of physicians said that legislation allowing recreational marijuana did not change their approach to medical marijuana with patients. Family physicians were more likely to be in favor of legalization of recreational marijuana in 2020 than in 2011. CONCLUSIONS: Marijuana decriminalization and a robust marijuana economy in Colorado have not led to more family physicians recommending marijuana to patients, but there is now greater support for the legalization of recreational marijuana among family physicians.

LPCAT3 Inhibitors Remodel the Polyunsaturated Phospholipid Content of Human Cells and Protect from Ferroptosis.

LPCAT3 is an integral membrane acyltransferase in the Lands cycle responsible for generating C20:4 phospholipids and has been implicated in key biological processes such as intestinal lipid absorption, lipoprotein assembly, and ferroptosis. Small-molecule inhibitors of LPCAT3 have not yet been described and would offer complementary tools to genetic models of LPCAT3 loss, which causes neonatal lethality in mice. Here, we report the discovery by high-throughput screening of a class of potent, selective, and cell-active inhibitors of LPCAT3. We provide evidence that these compounds inhibit LPCAT3 in a biphasic manner, possibly reflecting differential activity at each subunit of the LPCAT3 homodimer. LPCAT3 inhibitors cause rapid rewiring of polyunsaturated phospholipids in human cells that mirrors the changes observed in LPCAT3-null cells. Notably, these changes include not only the suppression of C20:4 phospholipids but also corresponding increases in C22:4 phospholipids, providing a potential mechanistic explanation for the partial but incomplete protection from ferroptosis observed in cells with pharmacological or genetic disruption of LPCAT3.

Profiling of MicroRNA Targets Using Activity-Based Protein Profiling: Linking Enzyme Activity to MicroRNA-185 Function.

MicroRNAs (miRNAs) act as cellular signal transducers through repression of protein translation. Elucidating targets using bioinformatics and traditional quantitation methods is often insufficient to uncover global miRNA function. Herein, alteration of protein function caused by miRNA-185 (miR-185), an immunometabolic miRNA, was determined using activity-based protein profiling, transcriptomics, and lipidomics. Fluorophosphonate-based activity-based protein profiling of miR-185-induced changes to human liver cells revealed that exclusively metabolic serine hydrolase enzymes were regulated in activity, some with roles in lipid and endocannabinoid metabolism. Lipidomic analysis linked enzymatic changes to levels of cellular lipid species, such as components of very-low-density lipoprotein particles. Additionally, inhibition of one miR-185 target, monoglyceride lipase, led to decreased hepatitis C virus levels in an infectious model. Overall, the approaches used here were able to identify key functional changes in serine hydrolases caused by miR-185 that are targetable pharmacologically, such that a small molecule inhibitor can recapitulate the miRNA phenotype.

Targeting glioblastoma signaling and metabolism with a re-purposed brain-penetrant drug.

The highly lethal brain cancer glioblastoma (GBM) poses a daunting challenge because the blood-brain barrier renders potentially druggable amplified or mutated oncoproteins relatively inaccessible. Here, we identify sphingomyelin phosphodiesterase 1 (SMPD1), an enzyme that regulates the conversion of sphingomyelin to ceramide, as an actionable drug target in GBM. We show that the highly brain-penetrant antidepressant fluoxetine potently inhibits SMPD1 activity, killing GBMs, through inhibition of epidermal growth factor receptor (EGFR) signaling and via activation of lysosomal stress. Combining fluoxetine with temozolomide, a standard of care for GBM, causes massive increases in GBM cell death and complete tumor regression in mice. Incorporation of real-world evidence from electronic medical records from insurance databases reveals significantly increased survival in GBM patients treated with fluoxetine, which was not seen in patients treated with other selective serotonin reuptake inhibitor (SSRI) antidepressants. These results nominate the repurposing of fluoxetine as a potentially safe and promising therapy for patients with GBM and suggest prospective randomized clinical trials.

Discovery and Optimization of Selective and in Vivo Active Inhibitors of the Lysophosphatidylserine Lipase α/ß-Hydrolase Domain-Containing 12 (ABHD12).

ABHD12 is a membrane-bound hydrolytic enzyme that acts on the lysophosphatidylserine (lyso-PS) and lysophosphatidylinositol (lyso-PI) classes of immunomodulatory lipids. Human and mouse genetic studies point to a key role for the ABHD12-(lyso)-PS/PI pathway in regulating (neuro)immunological functions in both the central nervous system and periphery. Selective inhibitors of ABHD12 would offer valuable pharmacological probes to complement genetic models of ABHD12-regulated (lyso)-PS/PI metabolism and signaling. Here, we provide a detailed description of the discovery and activity-based protein profiling (ABPP) guided optimization of reversible thiourea inhibitors of ABHD12 that culminated in the identification of DO264 as a potent, selective, and in vivo active ABHD12 inhibitor. We also show that DO264, but not a structurally related inactive control probe (S)-DO271, augments inflammatory cytokine production from human THP-1 macrophage cells. The in vitro and in vivo properties of DO264 designate this compound as a suitable chemical probe for studying the biological functions of ABHD12-(lyso)-PS/PI pathways.

A Qualitative Study on the Impact of First Steps-A Peer-led Educational Intervention for People Newly Diagnosed with Parkinson's Disease.

Aim: The dual aim of this research was to consider the impact of providing the First Steps program on the stories of people with Parkinson's Disease (PD) and to investigate the psychosocial and emotional mechanisms which may explain this impact. Methods: A qualitative study using a subtle realist paradigm and hermeneutic phenomenological methodology was undertaken. A single semi-structured interview was used to consider the impact and experiences of people with PD who completed either the intervention (2-day peer-led behavior intervention using storytelling 6-8 weeks apart) or received telephone support calls as part of the active control group. Descriptive statistics and a narrative analysis were undertaken on the results. Results: Forty-two participants were invited to participate, forty of whom completed the interview. This included 18 from the intervention group and 22 from the active control group. The intervention group identified the value of the program as worth-while, demonstrating improved exercise behavior and coping mechanisms following the intervention. Three major stories (the affirmed, the validated and the transformed story) identified the impact of the intervention. Three internal mechanisms (perceived control, hope and action, and the individual's mind set) alongside three social mechanisms (social comparison, social control and the first opportunity to share with peers) appeared to explain this impact. Conclusion: This study provides exciting and novel evidence of the impact of a peer-led psycho-educational intervention for people newly diagnosed with PD. Further research is needed to consider the impact of stories-based approaches on participants and consider a critical evaluation of the mechanisms which may explain changes in stories and self-reported behaviour.

Oncogene Amplification in Growth Factor Signaling Pathways Renders Cancers Dependent on Membrane Lipid Remodeling.

Advances in DNA sequencing technologies have reshaped our understanding of the molecular basis of cancer, providing a precise genomic view of tumors. Complementary biochemical and biophysical perspectives of cancer point toward profound shifts in nutrient uptake and utilization that propel tumor growth and major changes in the structure of the plasma membrane of tumor cells. The molecular mechanisms that bridge these fundamental aspects of tumor biology remain poorly understood. Here, we show that the lysophosphatidylcholine acyltransferase LPCAT1 functionally links specific genetic alterations in cancer with aberrant metabolism and plasma membrane remodeling to drive tumor growth. Growth factor receptor-driven cancers are found to depend on LPCAT1 to shape plasma membrane composition through enhanced saturated phosphatidylcholine content that is, in turn, required for the transduction of oncogenic signals. These results point to a genotype-informed strategy that prioritizes lipid remodeling pathways as therapeutic targets for diverse cancers.

Competencies to Guide a Leadership Curriculum for Family Medicine Chief Residents.

BACKGROUND AND OBJECTIVES: Chief resident leadership competencies are neither clear nor standardized. The goal of this project was to identify specific leadership skills for chief residents and to develop a self-assessment tool. METHODS: Chief residents from 10 family medicine residencies participated in focus groups to identify leadership skills required to be an effective chief resident. The ideas generated by participants were grouped into 10 competencies and a self-assessment tool was developed. The tool has been used to help chief residents self-assess their leadership strengths and weaknesses, and to identify teaching priorities for biannual leadership workshops. RESULTS: The self-assessment instrument was completed by 83 chief residents over 5 years. Mean ratings range from 3.19 to 3.57 on a 5-point scale (low to high competency). The self-ratings of residents starting their chief year compared to residents at the end of their chief year showed an increase in 9 of the 10 competencies. CONCLUSIONS: The leadership competencies are a useful tool to identify training priorities and to help chief residents or other leaders within a residency program identify skills for further development.

Lack of Communication about Medical Marijuana Use between Doctors and Their Patients.

INTRODUCTION: Medical marijuana is now permitted in most states, but it is not clear whether primary care physicians (PCPs) are aware of or recommend its use in their patients. METHODS: We distributed paired surveys to PCPs and their patients to assess the frequency of patient marijuana use and communication with PCPs about use. RESULTS: Of 242 patients surveyed, 22% reported marijuana use in the past 6 months, and 61% of these identified as medical marijuana users. PCPs did not complete state forms to recommend medical marijuana for any of the surveyed medical marijuana users. PCPs were aware of marijuana use in their patients only 53% of the time. PCPs identified conditions they believed could be adversely affected by marijuana use in 31% of users. CONCLUSION: There is poor communication between patients and PCPs about medical marijuana use, which is being sanctioned by physicians other than patients' PCPs. We suggest more frequent assessment of and discussion about marijuana use in patients, particularly in states that have approved medical marijuana.

Clinical Inquiries: Does exercise relieve vasomotor menopausal symptoms?

No. Exercise doesn't decrease the frequency or severity of vasomotor menopausal symptoms in perimenopausal and postmenopausal women (strength of recommendation: A, systematic review of randomized controlled trials [RCTs] and consistent RCT).

PURLs: Direct oral anticoagulants or warfarin for A fib?

A recent study evaluated the effectiveness of 3 direct oral anticoagulants and warfarin in patients with atrial fibrillation. So which agents came out on top?