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1.
Genome Biol ; 25(1): 81, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38553769

ABSTRACT

The use of single-cell technologies for clinical applications requires disconnecting sampling from downstream processing steps. Early sample preservation can further increase robustness and reproducibility by avoiding artifacts introduced during specimen handling. We present FixNCut, a methodology for the reversible fixation of tissue followed by dissociation that overcomes current limitations. We applied FixNCut to human and mouse tissues to demonstrate the preservation of RNA integrity, sequencing library complexity, and cellular composition, while diminishing stress-related artifacts. Besides single-cell RNA sequencing, FixNCut is compatible with multiple single-cell and spatial technologies, making it a versatile tool for robust and flexible study designs.


Subject(s)
Genomics , RNA , Humans , Animals , Mice , Tissue Fixation/methods , Reproducibility of Results , Sequence Analysis, RNA/methods , RNA/genetics , Genomics/methods , Single-Cell Analysis/methods
4.
AIDS ; 38(1): 21-29, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37289582

ABSTRACT

OBJECTIVES: Data are lacking on the virologic efficacy and durability of modern antiretroviral treatment (ART) regimens during pregnancy. We compared virologic outcomes at delivery among women receiving dolutegravir versus other ART and the rate of change of the initial pregnancy regimen. DESIGN: Single-site retrospective cohort between 2009 and 2019. METHODS: We used univariable and multivariable generalized estimating equations to model the relationship between the maternal ART anchor and the proportion of women with a detectable viral load (greater than or equal to 20 HIV RNA copies/mL of plasma) closest to delivery (suboptimal virologic control) and with a detectable viral load at any time in the third trimester. We also compared changes in ART during pregnancy. RESULTS: We evaluated 230 pregnancies in 173 mothers. Rates of optimal virologic control at delivery did not significantly differ in mothers who received dolutegravir (93.1%), rilpivirine (92.1%), boosted darunavir (82.6%), or efavirenz (76.9%) but were significantly lower among mothers receiving atazanavir (49.0%) or lopinavir (40.9%). The odds of having a detectable viral load at any time in the third trimester was also higher for atazanavir and lopinavir. Raltegravir, elvitegravir, or bictegravir were used in less than 10 mothers at delivery, which precluded statistical analyses. The frequency of change in ART was significantly higher in mothers who initially received elvitegravir (68%) or efavirenz (47%) than dolutegravir (18%). CONCLUSION: Dolutegravir-containing, rilpivirine-containing, and boosted darunavir-containing regimens conferred excellent virologic control in pregnancy. Atazanavir and lopinavir, elvitegravir, and efavirenz were associated with either high rates of virologic failure or regimen change during pregnancy.


Subject(s)
Anti-HIV Agents , HIV Infections , Female , Humans , Pregnancy , Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Pregnant Women , Lopinavir/therapeutic use , Atazanavir Sulfate/therapeutic use , Darunavir/therapeutic use , Retrospective Studies , Benzoxazines/therapeutic use , Rilpivirine/therapeutic use , Anti-Retroviral Agents/therapeutic use , Viral Load
5.
PLoS One ; 18(6): e0276473, 2023.
Article in English | MEDLINE | ID: mdl-37307279

ABSTRACT

BACKGROUND: Antiretroviral therapy (ART) decreases perinatal HIV transmission, but concerns exist regarding maternal and infant safety. We compared the incidence of congenital malformations and other adverse outcomes in pregnancies exposed to integrase inhibitor (INSTI) versus non-INSTI ART. SETTING: Single-site review of all pregnancies among women living with HIV between 2008 and 2018. METHODS: We used binomial family generalized estimating equations to model the relationship of congenital anomalies and pregnancy outcomes with exposure to INSTI or dolutegravir (DTG) versus non-INSTI ART. RESULTS: Among 257 pregnancies, 77 women received ≥1 INSTI (54 DTG, 14 elvitegravir, 15 raltegravir), 167 received non-INSTI, and 3 had missing data. Fifty congenital anomalies were identified in 36 infants. Infants with first-trimester DTG or any first-trimester INSTI exposure had higher odds of congenital anomalies than infants with first-trimester non-INSTI exposure (OR = 2.55; 95%CI = 1.07-6.10; OR = 2.61; 95%CI = 1.15-5.94, respectively). Infants with INSTI exposure after the second trimester had no increased odds of anomalies. Women with INSTI exposure had higher odds of preeclampsia (OR = 4.73; 95%CI = 1.70-13.19). Among women who received INSTI, grade ≥3 laboratory abnormalities were noted in 2.6% while receiving the INSTI and 3.9% while not receiving the INSTI, versus 16.2% in women who received non-INSTI. There was no association between INSTI exposure and other pregnancy outcomes. CONCLUSION: In our cohort, first-trimester INSTI exposure was associated with increased rates of congenital anomalies and use of INSTI during pregnancy was associated with preeclampsia. These findings underscore the need for continued monitoring of the safety of INSTI in pregnancy.


Subject(s)
Abnormalities, Drug-Induced , HIV Integrase Inhibitors , Maternal Exposure , Infant , HIV Infections/drug therapy , HIV Integrase Inhibitors/adverse effects , HIV Integrase Inhibitors/therapeutic use , Maternal Exposure/adverse effects , Abnormalities, Drug-Induced/epidemiology , Pregnancy Trimester, First , Pre-Eclampsia/chemically induced , Anti-Retroviral Agents/adverse effects , Retrospective Studies , Cohort Studies , Humans , Male , Female , Pregnancy , Infant, Newborn
7.
Clin Gastroenterol Hepatol ; 21(6): 1598-1606.e5, 2023 06.
Article in English | MEDLINE | ID: mdl-36642291

ABSTRACT

BACKGROUND & AIMS: Safety of biologic agents is a key consideration in patients with inflammatory bowel disease (IBD) and active or recent cancer. We compared the safety of tumor necrosis factor (TNF)-α antagonists vs non-TNF biologics in patients with IBD with active or recent cancer. METHODS: We conducted a multicenter retrospective cohort study of patients with IBD and either active cancer (cohort A) or recent prior cancer (within ≤5 years; cohort B) who were treated with TNFα antagonists or non-TNF biologics after their cancer diagnosis. Primary outcomes were progression-free survival (cohort A) or recurrence-free survival (cohort B). Safety was compared using inverse probability of treatment weighting with propensity scores. RESULTS: In cohort A, of 125 patients (483.8 person-years of follow-up evaluation) with active cancer (age, 54 ± 15 y, 75% solid-organ malignancy), 10 of 55 (incidence rate [IR] per 100 py, 4.4) and 9 of 40 (IR, 10.4) patients treated with TNFα antagonists and non-TNF biologics had cancer progression, respectively. There was no difference in the risk of progression-free survival between TNFα antagonists vs non-TNF biologics (hazard ratio, 0.76; 95% CI, 0.25-2.30). In cohort B, of 170 patients (513 person-years of follow-up evaluation) with recent prior cancer (age, 53 ± 15 y, 84% solid-organ malignancy; duration of remission, 19 ± 19 mo), 8 of 78 (IR, 3.4) and 5 of 66 (IR 3.7) patients treated with TNFα antagonists and non-TNF biologics had cancer recurrence, respectively. The risk of recurrence-free survival was similar between both groups (hazard ratio, 0.94; 95% CI, 0.24-3.77). CONCLUSIONS: In patients with IBD with active or recent cancer, TNFα antagonists and non-TNF biologics have comparable safety. The choice of biologic should be dictated by IBD disease severity in collaboration with an oncologist.


Subject(s)
Biological Products , Inflammatory Bowel Diseases , Neoplasms , Humans , Adult , Middle Aged , Aged , Tumor Necrosis Factor-alpha , Biological Factors , Retrospective Studies , Inflammatory Bowel Diseases/drug therapy , Inflammatory Bowel Diseases/chemically induced , Neoplasms/epidemiology , Neoplasms/chemically induced , Tumor Necrosis Factor Inhibitors , Biological Products/adverse effects
8.
Mayo Clin Proc Innov Qual Outcomes ; 6(5): 484-487, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35966031

ABSTRACT

Although corticosteroid therapy is the standard of care for all patients hospitalized with severe coronavirus disease 2019 (COVID-19), the studies demonstrating the mortality-benefit ratio of corticosteroids were limited to fully evaluate their adverse effects. To determine the severity of corticosteroid-induced hyperglycemia in patients with and without diabetes mellitus, we retrospectively collected data from the medical records of patients hospitalized with COVID-19 before and after corticosteroids were the standard of care. Corticosteroid-induced hyperglycemia was more severe in patients hospitalized with COVID-19 with diabetes than those without diabetes. Additionally, patients with diabetes required higher doses of correctional insulin per day when on corticosteroid therapy, suggesting that intensive point-of-care glucose monitoring could be limited in patients without diabetes mellitus and support cautionary use of corticosteroids in patients with COVID-19 discharged with supplemental oxygen.

9.
Matern Child Health J ; 26(10): 1976-1982, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36002697

ABSTRACT

INTRODUCTION: Despite significant improvements in recent years, maternal and neonatal health outcomes remain poor in many regions of the world. One such area is in the remote mountainous regions of Nepal. The purpose of this study is to describe the current antenatal care practices and delivery support in a mountainous district of Nepal. METHODS: This study took place in Solukhumbu District between December 2015 and February 2018. A household survey was created using evidence-based maternal and neonatal care indicators. Women who had delivered within the previous two years were surveyed regarding antenatal and delivery care they received. A standardized health facility survey was used to evaluate the operational status of health facilities. The study was approved by the Nepal Ministry of Health and the University of Utah IRB. RESULTS: A total of 487 households and 19 facilities were surveyed. 35.7% (174/487) of deliveries occurred in a health facility (hospital, primary health care center or birthing center). 35.2% (171/486) of deliveries were attended by a skilled birth attendant. 52.8% (47/89) of women who did not deliver in a facility noted that transportation issues and not having sufficient time to travel during labor prevented them from delivering in a facility. No health posts had staff trained in obstetric and neonatal emergencies. DISCUSSION: The majority of women in Solukhumbu District do not receive high quality antenatal and delivery care. An intervention that would make antenatal care and delivery support more accessible could improve maternal and infant outcomes in this district and other similar regions.


Subject(s)
Birthing Centers , Maternal Health Services , Perinatal Care , Child , Delivery, Obstetric , Female , Health Facilities , Health Services Accessibility , Humans , Infant, Newborn , Nepal/epidemiology , Pregnancy , Prenatal Care
10.
Front Pediatr ; 10: 894627, 2022.
Article in English | MEDLINE | ID: mdl-35783327

ABSTRACT

Background: Many women living with HIV (WLHIV) are co-infected with cytomegalovirus (CMV), Toxoplasma gondii (T gondii), and/or hepatitis C virus (HCV). The rates of congenital or perinatal transmission of these co-infections are not well defined in the current era, when most WLHIV receive antiretroviral therapy (ART) during pregnancy. Methods: Retrospective review of infants of WLHIV born between 2009-2019. Mothers were screened for antibodies to CMV, T. gondii, and HCV; chronic HCV infection was confirmed using plasma RNA PCR. Infants whose mothers had positive/unknown serostatus were screened for CMV using urine or saliva DNA PCR or culture at ≤3 weeks of life; T. gondii using serology at ≤1 month; and HCV using plasma RNA PCR at ≤6 months and serology at ≥12 months. Results: The study included 264 infants from 255 pregnancies in 191 mothers. At delivery, the median (IQR) CD4 count was 569 (406-748) cells/mm3 and plasma HIV load was 0 (0-24) RNA copies/mL. Among 243 infants born to CMV-seropositive (209) or CMV-missed serostatus (25) mothers, 163 (67.1%) were tested for CMV. Four infants had CMV detected, resulting in a rate of congenital infection of 2.5%. Among 65 infants from 54 (21.2%) pregnancies in T. gondii-seropositive women and 8 in women with unknown T. gondii-serostatus, one acquired congenital toxoplasmosis in the setting of acute maternal T. gondii infection. There were no episodes of vertical transmission from mothers with latent toxoplasmosis. Among 18 infants from 13 (5.1%) pregnancies in HCV RNA PCR-positive women and 4 in women with unknown HCV serostatus, there were no congenital or perinatal HCV transmissions. Conclusions: In a US cohort of pregnant WLHIV on ART, we identified high maternal CMV seroprevalence and a high rate of congenital CMV infection. We did not identify any congenital or perinatal transmissions of T. gondii or HCV among mothers who had latent or chronic infections. Our data support screening pregnant WLHIV and their infants for CMV and suggest that the rates of congenital and perinatal T. gondii and HCV infections among infants born to WLHIV on ART may be lower in the era of effective ART.

11.
J Nutr Health Aging ; 26(6): 637-651, 2022.
Article in English | MEDLINE | ID: mdl-35718874

ABSTRACT

Sarcopenia and frailty are highly prevalent conditions in older hospitalized patients, which are associated with a myriad of adverse clinical outcomes. This paper, prepared by a multidisciplinary expert working group from the Australian and New Zealand Society for Sarcopenia and Frailty Research (ANZSSFR), provides an up-to-date overview of current evidence and recommendations based on a narrative review of the literature for the screening, diagnosis, and management of sarcopenia and frailty in older patients within the hospital setting. It also includes suggestions on potential pathways to implement change to encourage widespread adoption of these evidence-informed recommendations within hospital settings. The expert working group concluded there was insufficient evidence to support any specific screening tool for sarcopenia and recommends an assessment of probable sarcopenia/sarcopenia using established criteria for all older (≥65 years) hospitalized patients or in younger patients with conditions (e.g., comorbidities) that may increase their risk of sarcopenia. Diagnosis of probable sarcopenia should be based on an assessment of low muscle strength (grip strength or five times sit-to-stand) with sarcopenia diagnosis including low muscle mass quantified from dual energy X-ray absorptiometry, bioelectrical impedance analysis or in the absence of diagnostic devices, calf circumference as a proxy measure. Severe sarcopenia is represented by the addition of impaired physical performance (slow gait speed). All patients with probable sarcopenia or sarcopenia should be investigated for causes (e.g., chronic/acute disease or malnutrition), and treated accordingly. For frailty, it is recommended that all hospitalized patients aged 70 years and older be screened using a validated tool [Clinical Frailty Scale (CFS), Hospital Frailty Risk Score, the FRAIL scale or the Frailty Index]. Patients screened as positive for frailty should undergo further clinical assessment using the Frailty Phenotype, Frailty Index or information collected from a Comprehensive Geriatric Assessment (CGA). All patients identified as frail should receive follow up by a health practitioner(s) for an individualized care plan. To treat older hospitalized patients with probable sarcopenia, sarcopenia, or frailty, it is recommended that a structured and supervised multi-component exercise program incorporating elements of resistance (muscle strengthening), challenging balance, and functional mobility training be prescribed as early as possible combined with nutritional support to optimize energy and protein intake and correct any deficiencies. There is insufficient evidence to recommend pharmacological agents for the treatment of sarcopenia or frailty. Finally, to facilitate integration of these recommendations into hospital settings organization-wide approaches are needed, with the Spread and Sustain framework recommended to facilitate organizational culture change, with the help of 'champions' to drive these changes. A multidisciplinary team approach incorporating awareness and education initiatives for healthcare professionals is recommended to ensure that screening, diagnosis and management approaches for sarcopenia and frailty are embedded and sustained within hospital settings. Finally, patients and caregivers' education should be integrated into the care pathway to facilitate adherence to prescribed management approaches for sarcopenia and frailty.


Subject(s)
Frailty , Sarcopenia , Aged , Aged, 80 and over , Australia , Frail Elderly , Frailty/diagnosis , Frailty/therapy , Geriatric Assessment , Hand Strength/physiology , Humans , New Zealand , Sarcopenia/diagnosis , Sarcopenia/therapy
12.
Clin Gastroenterol Hepatol ; 20(2): 455-457, 2022 02.
Article in English | MEDLINE | ID: mdl-33647465

ABSTRACT

Microscopic colitis (MC) is a disease characterized by chronic watery diarrhea secondary to colonic inflammation. Endoscopically, the mucosa is usually normal but biopsies show characteristic histologic findings.1.


Subject(s)
Colitis, Microscopic , Colitis , Antibodies, Monoclonal, Humanized/therapeutic use , Biopsy , Chronic Disease , Colitis/drug therapy , Colitis/pathology , Colitis, Microscopic/drug therapy , Colitis, Microscopic/pathology , Diarrhea/drug therapy , Diarrhea/pathology , Humans
13.
J Nutr Health Aging ; 25(7): 824-853, 2021.
Article in English | MEDLINE | ID: mdl-34409961

ABSTRACT

The human ageing process is universal, ubiquitous and inevitable. Every physiological function is being continuously diminished. There is a range between two distinct phenotypes of ageing, shaped by patterns of living - experiences and behaviours, and in particular by the presence or absence of physical activity (PA) and structured exercise (i.e., a sedentary lifestyle). Ageing and a sedentary lifestyle are associated with declines in muscle function and cardiorespiratory fitness, resulting in an impaired capacity to perform daily activities and maintain independent functioning. However, in the presence of adequate exercise/PA these changes in muscular and aerobic capacity with age are substantially attenuated. Additionally, both structured exercise and overall PA play important roles as preventive strategies for many chronic diseases, including cardiovascular disease, stroke, diabetes, osteoporosis, and obesity; improvement of mobility, mental health, and quality of life; and reduction in mortality, among other benefits. Notably, exercise intervention programmes improve the hallmarks of frailty (low body mass, strength, mobility, PA level, energy) and cognition, thus optimising functional capacity during ageing. In these pathological conditions exercise is used as a therapeutic agent and follows the precepts of identifying the cause of a disease and then using an agent in an evidence-based dose to eliminate or moderate the disease. Prescription of PA/structured exercise should therefore be based on the intended outcome (e.g., primary prevention, improvement in fitness or functional status or disease treatment), and individualised, adjusted and controlled like any other medical treatment. In addition, in line with other therapeutic agents, exercise shows a dose-response effect and can be individualised using different modalities, volumes and/or intensities as appropriate to the health state or medical condition. Importantly, exercise therapy is often directed at several physiological systems simultaneously, rather than targeted to a single outcome as is generally the case with pharmacological approaches to disease management. There are diseases for which exercise is an alternative to pharmacological treatment (such as depression), thus contributing to the goal of deprescribing of potentially inappropriate medications (PIMS). There are other conditions where no effective drug therapy is currently available (such as sarcopenia or dementia), where it may serve a primary role in prevention and treatment. Therefore, this consensus statement provides an evidence-based rationale for using exercise and PA for health promotion and disease prevention and treatment in older adults. Exercise prescription is discussed in terms of the specific modalities and doses that have been studied in randomised controlled trials for their effectiveness in attenuating physiological changes of ageing, disease prevention, and/or improvement of older adults with chronic disease and disability. Recommendations are proposed to bridge gaps in the current literature and to optimise the use of exercise/PA both as a preventative medicine and as a therapeutic agent.


Subject(s)
Aging/physiology , Exercise , Frailty , Health Promotion , Quality of Life , Aged , Exercise/physiology , Exercise Therapy/standards , Frailty/prevention & control , Humans , Phenotype , Sedentary Behavior
14.
Nucleic Acids Res ; 49(18): e105, 2021 10 11.
Article in English | MEDLINE | ID: mdl-34255842

ABSTRACT

Translation of eukaryotic mRNAs begins with binding of their m7G cap to eIF4E, followed by recruitment of other translation initiation factor proteins. We describe capCLIP, a novel method to comprehensively capture and quantify the eIF4E (eukaryotic initiation factor 4E) 'cap-ome' and apply it to examine the biological consequences of eIF4E-cap binding in distinct cellular contexts. First, we use capCLIP to identify the eIF4E cap-omes in human cells with/without the mTORC1 (mechanistic target of rapamycin, complex 1) inhibitor rapamycin, there being an emerging consensus that rapamycin inhibits translation of TOP (terminal oligopyrimidine) mRNAs by displacing eIF4E from their caps. capCLIP reveals that the representation of TOP mRNAs in the cap-ome is indeed systematically reduced by rapamycin, thus validating our new methodology. capCLIP also refines the requirements for a functional TOP sequence. Second, we apply capCLIP to probe the consequences of phosphorylation of eIF4E. We show eIF4E phosphorylation reduces overall eIF4E-mRNA association and, strikingly, causes preferential dissociation of mRNAs with short 5'-UTRs. capCLIP is a valuable new tool to probe the function of eIF4E and of other cap-binding proteins such as eIF4E2/eIF4E3.


Subject(s)
Eukaryotic Initiation Factor-4E/metabolism , RNA Caps/metabolism , RNA, Messenger/metabolism , HeLa Cells , Humans , Protein Binding , Protein Biosynthesis
15.
J Nutr Health Aging ; 25(1): 25-32, 2021.
Article in English | MEDLINE | ID: mdl-33367459

ABSTRACT

BACKGROUND: Osteosarcopenia is a geriatric syndrome defined by the concomitant presence of osteopenia/osteoporosis (loss of bone mineral density (BMD)) and sarcopenia (loss of muscle mass and/or function), which increases the risk of falls, fractures, and premature mortality. OBJECTIVE: To examine the efficacy of non-pharmacological (exercise and/or nutritional) interventions on musculoskeletal measures and outcomes in osteosarcopenic adults by reviewing findings from randomized controlled trials (RCTs). METHODS: This review was registered at PROSPERO (registration number: CRD42020179292) and conducted in accordance with the PRISMA guidelines. Electronic databases were searched for RCTs assessing the effect of at least one non-pharmacological intervention (any form of exercise and/or supplementation with protein, vitamin D, calcium or creatine) on any musculoskeletal measure/outcome of interest (BMD, bone strength/turnover, muscle mass and strength, physical performance, falls/fractures) in adults with osteosarcopenia as defined by any proposed criteria. RESULTS: Two RCTs (of n=106 older osteosarcopenic adults (≥65 years)) assessing the effects of progressive resistance training (RT) (via resistance bands or machines; 2-3 times/week; ~60 minutes in duration) were eligible for inclusion. The two RCTs demonstrated moderate quality evidence that RT increases muscle mass, strength, and quality, with changes in strength and quality occurring before muscle mass (12 vs 28 weeks). There was low quality evidence that RT increases lumbar spine BMD and maintains total hip BMD when performed for 12 and 18 months, respectively, and moderate quality evidence that RT has no effect on markers of bone turnover or physical performance. No major adverse effects were recorded in either of the RCTs. There were no eligible RCTs examining the impact of nutritional interventions. CONCLUSION: Chronic RT is safe and effective at potentiating gains in muscle mass, strength, and quality, and increasing or maintaining BMD in older osteosarcopenic adults. No RCT has examined the effects of protein, vitamin D, calcium, or creatine against a control/placebo in this high-risk population.


Subject(s)
Osteoporosis/therapy , Sarcopenia/therapy , Aged , Female , Humans , Male , Middle Aged
17.
Cell Mol Life Sci ; 78(1): 249-270, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32170339

ABSTRACT

eIF4E plays key roles in protein synthesis and tumorigenesis. It is phosphorylated by the kinases MNK1 and MNK2. Binding of MNKs to eIF4G enhances their ability to phosphorylate eIF4E. Here, we show that mTORC1, a key regulator of mRNA translation and oncogenesis, directly phosphorylates MNK2 on Ser74. This suppresses MNK2 activity and impairs binding of MNK2 to eIF4G. These effects provide a novel mechanism by which mTORC1 signaling impairs the function of MNK2 and thereby decreases eIF4E phosphorylation. MNK2[S74A] knock-in cells show enhanced phosphorylation of eIF4E and S6K1 (i.e., increased mTORC1 signaling), enlarged cell size, and increased invasive and transformative capacities. MNK2[Ser74] phosphorylation was inversely correlated with disease progression in human prostate tumors. MNK inhibition exerted anti-proliferative effects in prostate cancer cells in vitro. These findings define a novel feedback loop whereby mTORC1 represses MNK2 activity and oncogenic signaling through eIF4E phosphorylation, allowing reciprocal regulation of these two oncogenic pathways.


Subject(s)
Eukaryotic Initiation Factor-4E/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Mechanistic Target of Rapamycin Complex 1/metabolism , Protein Serine-Threonine Kinases/metabolism , Animals , Cell Cycle Checkpoints/drug effects , Cell Line , Cell Proliferation/drug effects , Eukaryotic Initiation Factor-4E/antagonists & inhibitors , Humans , Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Intracellular Signaling Peptides and Proteins/genetics , Male , Mechanistic Target of Rapamycin Complex 1/antagonists & inhibitors , Mice , Mice, Inbred BALB C , Mice, Transgenic , Morpholines/pharmacology , Mutagenesis, Site-Directed , Phosphorylation/drug effects , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Protein Binding , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/genetics , Signal Transduction/drug effects , Tuberous Sclerosis Complex 2 Protein/genetics , Tuberous Sclerosis Complex 2 Protein/metabolism
18.
J Neurochem ; 157(4): 1086-1101, 2021 05.
Article in English | MEDLINE | ID: mdl-32892352

ABSTRACT

The regulation of protein synthesis is a vital and finely tuned process in cellular physiology. In neurons, this process is very precisely regulated, as which mRNAs undergo translation is highly dependent on context. One of the most prominent regulators of protein synthesis is the enzyme eukaryotic elongation factor kinase 2 (eEF2K) that regulates the elongation stage of protein synthesis. This kinase and its substrate, eukaryotic elongation factor 2 (eEF2) are important in processes such as neuronal development and synaptic plasticity. eEF2K is regulated by multiple mechanisms including Ca2+ -ions and the mTORC1 signaling pathway, both of which play key roles in neurological processes such as learning and memory. In such settings, the localized control of protein synthesis is of crucial importance. In this work, we sought to investigate how the localization of eEF2K is controlled and the impact of this on protein synthesis in neuronal cells. In this study, we used both SH-SY5Y neuroblastoma cells and mouse cortical neurons, and pharmacologically and/or genetic approaches to modify eEF2K function. We show that eEF2K activity and localization can be regulated by its binding partner Homer1b/c, a scaffolding protein known for its participation in calcium-regulated signaling pathways. Furthermore, our results indicate that this interaction is regulated by the mTORC1 pathway, through a known phosphorylation site in eEF2K (S396), and that it affects rates of localized protein synthesis at synapses depending on the presence or absence of this scaffolding protein.


Subject(s)
Elongation Factor 2 Kinase/metabolism , Homer Scaffolding Proteins/metabolism , Mechanistic Target of Rapamycin Complex 1/metabolism , Neurons/metabolism , Protein Biosynthesis/physiology , Animals , Bicuculline/pharmacology , Cells, Cultured , GABA-A Receptor Antagonists/pharmacology , Humans , Mice , Phosphorylation , Protein Biosynthesis/drug effects , Signal Transduction/drug effects
19.
Res Q Exerc Sport ; 92(4): 630-638, 2021 Dec.
Article in English | MEDLINE | ID: mdl-32658597

ABSTRACT

Accurate determinations of individuals' one-repetition maximum (1RM) are critical when evaluating the effectiveness of an exercise intervention involving progressive resistance training (RT). Traditional ("bottom-up"; BT) testing methods involve progressions from low to maximal loads and are commonly used in clinical and laboratory environments. Concerns about the reliability of BT testing in certain populations suggest a different technique may be more effective. Purpose: To compare the reliability and effectiveness of traditional 1RM testing to a novel technique (TDT) involving progressive load reductions and a starting intensity equal to 130% of exercisers' estimated 1RM. Method: 70 healthy adults (age = 45.03 ± 25.64 y) with diverse RT experience were randomized into a reliability testing trial (RTT; n = 33) or an optimal method trial (OMT; n = 37). Subjects in the RTT performed either TDT or BT on 3 occasions separated by ≥ 72 hours, while subjects in the OMT performed each method once in random order on separate days. Results: No significant differences in percent coefficient of variation were observed between BT and TDT for either exercise used in the study (pneumatic seated chest press: Hedge's g = 0.25, p = .49; pneumatic recumbent leg press: Hedge's g = 0.12, p = .74). TDT was not found to produce significantly higher 1RM values than BT in any group. Conclusion: TDT does not appear to facilitate more reliable 1RM estimates than BT. Further research is needed to determine the stability of these findings across levels of exercisers' age, sex, and previous RT experience.


Subject(s)
Muscle Strength , Resistance Training , Adult , Aged , Exercise , Humans , Middle Aged , Reproducibility of Results , Weight Lifting , Young Adult
20.
Mol Metab ; 42: 101054, 2020 12.
Article in English | MEDLINE | ID: mdl-32712434

ABSTRACT

OBJECTIVES: Diet-driven obesity is increasingly widespread. Its consequences pose major challenges to human health and health care systems. There are MAP kinase-interacting kinases (MNKs) in mice, MNK1 and MNK2. Studies have demonstrated that mice lacking either MNK1 or MNK2 were partially protected against high-fat diet (HFD)-induced weight gain and insulin resistance. The aims of this study were to evaluate the phenotype of mice lacking both MNKs when given an HFD, to assess whether pharmacological inhibition of MNK function also protects against diet-induced obesity (DIO) and its consequences and to probe the mechanisms underlying such protection. METHODS: Male wild-type (WT) C57Bl6 mice or mice lacking both MNK1 and MNK2 (double knockout, DKO) were fed an HFD or control diet (CD) for up to 16 weeks. In a separate study, WT mice were also given an HFD for 6 weeks, after which half were treated with the recently-developed MNK inhibitor ETC-206 daily for 10 more weeks while continuing an HFD. Metabolites and other parameters were measured, and the expression of selected mRNAs and proteins was assessed. RESULTS: MNK-DKO mice were almost completely protected from HFD-induced obesity. Higher energy expenditure (EE) in MNK-DKO mice was observed, which probably reflects the changes in a number of genes or proteins linked to lipolysis, mitochondrial function/biogenesis, oxidative metabolism, and/or ATP consumption. The MNK inhibitor ETC-206 also prevented HFD-induced weight gain, confirming that the activity of the MNKs facilitates weight gain due to excessive caloric consumption. CONCLUSIONS: Disabling MNKs in mice, either genetically or pharmacologically, strongly prevents weight gain on a calorie-rich diet. This finding likely results from increased energy utilisation, involving greater ATP consumption, mitochondrial oxidative metabolism, and other processes.


Subject(s)
Protein Serine-Threonine Kinases/genetics , Weight Gain/drug effects , Animals , Cell Respiration , Diet, High-Fat , Energy Metabolism , Insulin/metabolism , Insulin Resistance/genetics , Insulin Resistance/physiology , Lipid Metabolism , Male , Mice , Mice, Inbred C57BL , Mitogen-Activated Protein Kinase Kinases/metabolism , Obesity/metabolism , Oxidative Stress/drug effects , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/metabolism , Weight Gain/genetics , Weight Gain/physiology
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