Markers Of Atrophy Research Articles

Dark tea extract attenuates age-related muscle loss by suppressing oxidative stress and inflammation in skeletal muscle of mice

Dark tea (DT), a tea post-fermented by the Eurotium cristatum fungus, is known to attenuate oxidative damage and chronic inflammation. It also extends the lifespan of Caenorhabditis elegans fed a high-sugar diet. However, its impact on age-related muscle loss in mice is unclear. We divided 65-week-old male C57BL/6 mice into three groups: old control received the AIN-93 M diet, while the 0.15DT and 0.3DT groups had 0.15 % and 0.3 % DT for 9 weeks. As a result, DT improved grip strength, treadmill performance, muscle weight, and size in aged mice. It reduced cellular senescence, muscle atrophy markers, and angiopoietin-like 2 expression, while increasing sirtuin 1 protein levels in aged mice. Additionally, DT lowered malondialdehyde content and pro-inflammatory cytokine levels and enhanced total antioxidant capacity and enzymes, ultimately attenuating mitochondrial dysfunction in skeletal muscle. Therefore, our results suggest DT attenuates age-related muscle atrophy by alleviating oxidative stress, mitochondrial dysfunction, and inflammation.

Investigation of perfusion impairment in degenerative cervical myelopathy beyond the site of cord compression

The aim of this study was to determine tissue-specific blood perfusion impairment of the cervical cord above the compression site in patients with degenerative cervical myelopathy (DCM) using intravoxel incoherent motion (IVIM) imaging. A quantitative MRI protocol, including structural and IVIM imaging, was conducted in healthy controls and patients. In patients, T2-weighted scans were acquired to quantify intramedullary signal changes, the maximal canal compromise, and the maximal cord compression. T2*-weighted MRI and IVIM were applied in all participants in the cervical cord (covering C1–C3 levels) to determine white matter (WM) and grey matter (GM) cross-sectional areas (as a marker of atrophy), and tissue-specific perfusion indices, respectively. IVIM imaging resulted in microvascular volume fraction (F\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$F$$\\end{document}), blood velocity (D∗\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$D^{*}$$\\end{document}), and blood flow (F·D∗\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$F \\cdot D^{*}$$\\end{document}) indices. DCM patients additionally underwent a standard neurological clinical assessment. Regression analysis assessed associations between perfusion parameters, clinical outcome measures, and remote spinal cord atrophy. Twenty-nine DCM patients and 30 healthy controls were enrolled in the study. At the level of stenosis, 11 patients showed focal radiological evidence of cervical myelopathy. Above the stenosis level, cord atrophy was observed in the WM (− 9.3%; p = 0.005) and GM (− 6.3%; p = 0.008) in patients compared to healthy controls. Blood velocity (BV) and blood flow (BF) indices were decreased in the ventral horns of the GM (BV: − 20.1%, p = 0.0009; BF: − 28.2%, p = 0.0008), in the ventral funiculi (BV: − 18.2%, p = 0.01; BF: − 21.5%, p = 0.04) and lateral funiculi (BV: − 8.5%, p = 0.03; BF: − 16.5%, p = 0.03) of the WM, across C1–C3 levels. A decrease in microvascular volume fraction was associated with GM atrophy (R = 0.46, p = 0.02). This study demonstrates tissue-specific cervical perfusion impairment rostral to the compression site in DCM patients. IVIM indices are sensitive to remote perfusion changes in the cervical cord in DCM and may serve as neuroimaging biomarkers of hemodynamic impairment in future studies. The association between perfusion impairment and cervical cord atrophy indicates that changes in hemodynamics caused by compression may contribute to the neurodegenerative processes in DCM.

Eldecalcitol prevents muscle loss and osteoporosis in disuse muscle atrophy via NF-κB signaling in mice

We investigated the effect of eldecalcitol on disuse muscle atrophy. C57BL/6J male mice aged 6 weeks were randomly assigned to control, tail suspension (TS), and TS-eldecalcitol–treated groups and were injected intraperitoneally twice a week with either vehicle (control and TS) or eldecalcitol at 3.5 or 5 ng for 3 weeks. Grip strength and muscle weights of the gastrocnemius (GAS), tibialis anterior (TA), and soleus (SOL) were determined. Oxidative stress was evaluated by malondialdehyde, superoxide dismutase, glutathione peroxidase, and catalase. Bone microarchitecture was analyzed using microcomputed tomography. The effect of eldecalcitol on C2C12 myoblasts was analyzed by measuring myofibrillar protein MHC and the atrophy markers Atrogin-1 and MuRF-1 using immunofluorescence. The influence of eldecalcitol on NF-κB signaling pathway and vitamin D receptor (VDR) was assessed through immunofluorescence, (co)-immunoprecipitation, and VDR knockdown studies. Eldecalcitol increased grip strength (P < 0.01) and restored muscle loss in GAS, TA, and SOL (P < 0.05 to P < 0.001) induced by TS. An improvement was noted in bone mineral density and bone architecture in the eldecalcitol group. The impaired oxidative defense system was restored by eldecalcitol (P < 0.05 to P < 0.01 vs. TS). Eldecalcitol (10 nM) significantly inhibited the expression of MuRF-1 (P < 0.001) and Atrogin-1 (P < 0.01), increased the diameter of myotubes (P < 0.05), inhibited the expression of P65 and P52 components of NF-κB and P65 nuclear location, thereby inhibiting NF-κB signaling. Eldecalcitol promoted VDR binding to P65 and P52. VDR signaling is required for eldecalcitol-mediated anti-atrophy effects. In conclusion, eldecalcitol exerted its beneficial effects on disuse-induced muscle atrophy via NF-κB inhibition.

Association of Glycemic Variability With Imaging Markers of Vascular Burden, β-Amyloid, Brain Atrophy, and Cognitive Impairment.

We aimed to investigate the association between glycemic variability (GV) and neuroimaging markers of white matter hyperintensities (WMH), beta-amyloid (Aβ), brain atrophy, and cognitive impairment. This was a retrospective cohort study that included participants without dementia from a memory clinic. They all had Aβ PET, brain MRI, and standardized neuropsychological tests and had fasting glucose (FG) levels tested more than twice during the study period. We defined GV as the intraindividual visit-to-visit variability in FG levels. Multivariable linear regression and logistic regression were used to identify whether GV was associated with the presence of severe WMH and Aβ uptake with DM, mean FG levels, age, sex, hypertension, and presence of APOE4 allele as covariates. Mediation analyses were used to investigate the mediating effect of WMH and Aβ uptake on the relationship between GV and brain atrophy and cognition. Among the 688 participants, the mean age was 72.2 years, and the proportion of female participants was 51.9%. Increase in GV was predictive of the presence of severe WMH (coefficient [95% CI] 1.032 [1.012-1.054]; p = 0.002) and increased Aβ uptake (1.005 [1.001-1.008]; p = 0.007). Both WMH and increased Aβ uptake partially mediated the relationship between GV and frontal-executive dysfunction (GV → WMH → frontal-executive; direct effect, -0.319 [-0.557 to -0.080]; indirect effect, -0.050 [-0.091 to -0.008]) and memory dysfunction (GV → Aβ → memory; direct effect, -0.182 [-0.338 to -0.026]; indirect effect, -0.067 [-0.119 to -0.015]), respectively. In addition, increased Aβ uptake completely mediated the relationship between GV and hippocampal volume (indirect effect, -1.091 [-2.078 to -0.103]) and partially mediated the relationship between GV and parietal thickness (direct effect, -0.00101 [-0.00185 to -0.00016]; indirect effect, -0.00016 [-0.00032 to -0.000002]). Our findings suggest that increased GV is related to vascular and Alzheimer risk factors and neurodegenerative markers, which in turn leads to subsequent cognitive impairment. Furthermore, GV can be considered a potentially modifiable risk factor for dementia prevention.

Chronic atrophic gastritis: focus on diagnosis

Currently, chronic atrophic gastritis is a risk factor for the development of gastric cancer. Data on the prevalence of chronic atrophic gastritis in Russia and the world are limited. Among the adult population of St. Petersburg aged 21 to 81 years, the prevalence of histologically verified chronic atrophic gastritis is 5.3%. Moreover, the chances of developing chronic atrophic gastritis in people over the age of 60 years compared to the group of 45–59 years are 2.5 times higher (95% confidence interval 1.5–4.1).&#x0D; Morphological verification of the Operative Link for Gastritis Assessment diagnosis is not carried out in clinical practice in most cases. However, this method remains the most reliable method for timely verification of chronic atrophic gastritis, including chronic atrophic gastritis of mixed origin (autoimmune gastritis and Helicobacter pylori-associated gastritis), especially in the case of a seronegative variant of autoimmune gastritis.&#x0D; Also, in addition to the heterogeneity of epidemiological data on chronic atrophic gastritis, there is disagreement about how to confirm its etiology as well as about the correlation of serological markers of atrophy and histological stage.

DBC1maintains skeletal muscle integrity by enhancing myogenesis and preventing myofibre wasting.

Skeletal muscle atrophy, particularly ageing-related muscular atrophy such as sarcopenia, is a significant health concern. Despite its prevalence, the underlying mechanisms remain poorly understood, and specific approved medications are currently unavailable. Deleted in breast cancer 1 (DBC1) is a well-known regulator of senescence, metabolism or apoptosis. Recent reports suggest that DBC1 may also potentially regulate muscle function, as mice lacking DBC1 exhibit weakness and limpness. However, the function of DBC1 in skeletal muscle and its associated molecular mechanisms remain unknown, thus prompting the focus of this study. Tibialis anterior (TA) muscle-specific DBC1 knockdown C57BL/6J male mice were generated through a single injection of 2.00 E+11vg of adeno-associated virus 9 delivering single-guide RNA for DBC1. Grip strength and endurance were assessed 2months later, followed by skeletal muscle harvest. Muscle atrophy model was generated by cast immobilization of the mouse hindlimb for 2weeks. Molecular markers of atrophy were probed in muscles upon termination. Cardiotoxin (CTX) was injected in TA muscles of DBC1 knockdown mice, and muscle regeneration was assessed by immunohistochemistry, quantitative PCR and western blotting. DBC1 knockdown C2C12 cells and myotubes were investigated using immunofluorescence staining, Seahorse, immunohistology, fluorescence-activated cell sorting and RNA-sequencing analyses. DBC1 knockdown in skeletal muscle of young mice led to signatures of muscle atrophy, including a 28% reduction in muscle grip force (P=0.023), a 54.4% reduction in running distance (P=0.002), a 14.3% reduction in muscle mass (P=0.007) and significantly smaller myofibre cross-sectional areas (P<0.0001). DBC1 levels decrease in age-related or limb immobilization-induced atrophic mouse muscles and overexpress DBC1-attenuated atrophic phenotypes in these mice. Muscle regeneration was hampered in mice with CTX-induced muscle injury by DBC1 knockdown, as evidenced by reductions in myofibre cross-sectional areas of regenerating myofibres with centralized nuclei (P<0.0001), percentages of MyoG+ nuclei (P<0.0001) and fusion index (P<0.0001). DBC1 transcriptionally regulated mouse double minute 2 (MDM2), which mediated ubiquitination and degradation of forkhead box O3 (FOXO3). Increased FOXO3 proteins hampered myogenesis in DBC1 knockdown satellite cells by compromising around 50% of mitochondrial functions (P<0.001) and exacerbated atrophy in DBC1 knockdown myofibres by activating the ubiquitin-proteasome and autophagy-lysosome pathways. DBC1 is essential in maintaining skeletal muscle integrity by protecting against myofibres wasting and enhancing muscle regeneration via FOXO3. This research highlights the significance of DBC1 for healthy skeletal muscle function and its connection to muscular atrophy.

Association of ambient air pollution with cognitive functioning and structural brain damage: The Maastricht Study

AbstractBackgroundDementia prevention poses one of the biggest challenges to our ageing society (1,2). Next to individual modifiable risk factors, shared environmental risk factors have been linked to dementia risk. Exposure to air pollution has been identified as a new candidate risk factor which on a population level carries more risk than well‐established risk factors such as hypertension and type‐2 diabetes (1). This study aimed to investigate the association between exposure to air pollutants with cognitive functioning and markers of structural brain damage next to and above individual risk factors.MethodCross‐sectional data from the population‐based cohort (N = 4,154; mean age 59.27±8.54 years, 50.12% women) of The Maastricht Study (3) was used and matched to address‐based data from the Geoscience andHealth Cohort Consortium of average exposure to particulate matter (&lt;2.5mg and &lt;10mg), NO2 and soot over the years 2013‐2018. Cognitive functioning was assessed through a neuropsychological test battery. Standardized volumes of grey matter, white matter, cerebrospinal fluid, and presence of cerebral small vessel disease were derived from 3‐Tesla MRI. Individual risk factors were added as one covariate, using the validated Lifestyle for Brain Health score (4). Binary logistic and multiple linear regression analyses tested the associations between air pollutants and the outcome measures. Likelihood‐ratio tests were performed to compare the extensive models.ResultWe found a curvilinear association relating particulate matter exposure in the mid to higher range to lower grey matter and higher cerebrospinal fluid volume, independent of age, sex, education, and LIBRA score. There was no association between air pollutant exposure and cognitive functioning or markers of cerebral small vessel disease.ConclusionIn this population‐based cohort, average to high exposure to particulate matter was related to an increase in markers of brain atrophy, showing important implications for environmental and public health policymaking.

LPS-Induced Modifications in Macrophage Transcript and Secretion Profiles Are Linked to Muscle Wasting and Glucose Intolerance.

Macrophages are versatile immune cells that play crucial roles in tissue repair, immune defense, and the regulation of immune responses. In the context of skeletal muscle, they are vital for maintaining muscle homeostasis but macrophage-induced chronic inflammation can lead to muscle dysfunction, resulting in skeletal muscle atrophy characterized by reduced muscle mass and impaired insulin regulation and glucose uptake. Although the involvement of macrophage-secreted factors in inflammation-induced muscle atrophy is well-established, the precise intracellular signaling pathways and secretion factors affecting skeletal muscle homeostasis require further investigation. This study aimed to explore the regulation of macrophage-secreted factors and their impact on muscle atrophy and glucose metabolism. By employing RNA sequencing (RNA-seq) and proteome array, we uncovered that factors secreted by lipopolysaccharide (LPS)-stimulated macrophages upregulated markers of muscle atrophy and pro-inflammatory cytokines, while concurrently reducing glucose uptake in muscle cells. The RNA-seq analysis identified alterations in gene expression patterns associated with immune system pathways and nutrient metabolism. The utilization of gene ontology (GO) analysis and proteome array with macrophage-conditioned media revealed the involvement of macrophage-secreted cytokines and chemokines associated with muscle atrophy. These findings offer valuable insights into the regulatory mechanisms of macrophage-secreted factors and their contributions to muscle-related diseases.

Association of plasma Alzheimer’s and neurodegenerative disease biomarkers with brain volume loss and cognitive decline

AbstractBackgroundAlthough plasma Alzheimer’s disease (AD) and neurodegenerative disease biomarkers have been associated with reduced cognition and lower brain volume, few studies have examined whether plasma biomarkers measured in predominately cognitively unimpaired adults are associated with longitudinal brain volume loss and cognitive decline. Using data from the Baltimore Longitudinal Study of Aging (BLSA), we examined whether plasma biomarkers of AD pathology (Aß42/40, phosphorylated tau [pTau‐181]), reactive astrogliosis (glial fibrillary acidic protein [GFAP]), and neuronal injury (neurofilament light chain [NfL]) were associated with longitudinal brain volume loss and cognitive decline.MethodPlasma biomarkers (Aß42/40, pTau‐181, GFAP, NfL) were measured using Quanterix SIMOA assays. Baseline visits were considered the earliest visits that had concurrent 3T MRI scans and plasma biomarker measurements, and the earliest visits that had concurrent cognitive assessments and plasma biomarker measurements. Composite Z scores were computed to reflect 5 cognitive domains (Figure 1). Linear mixed effects models adjusted for baseline age, sex, race, education, estimated glomerular filtration rate, and total intracranial volume (brain volume analyses), were used to examine the association of plasma biomarkers with baseline and longitudinal brain volume and cognition. False Discovery Rate correction was used to adjust for multiple comparisons.ResultBrain volume analyses included 628 participants (mean age±SD: 71.0±10.2; Table 1) with an average of 3.3 MRI scans over 4.7 years. Cognition analyses included 686 participants (mean age±SD: 71.4±10.1) with an average of 3.9 cognitive assessments over 5.7 years. Although Aß42/40 was unrelated to brain volume changes, higher pTau‐181 was associated with longitudinal declines in total gray matter volume and regional declines in medial temporal regions. Higher GFAP was associated with longitudinal increases in ventricular volume, whereas NfL was not associated with brain volume change (Table 2). Both lower Aß42/40 and higher pTau‐181 were associated with a decline in verbal memory. Additionally, lower Aß42/40 was associated with a decline in visuospatial performance. Further, higher GFAP was associated with a decline in verbal fluency (Figure 1).ConclusionPlasma biomarkers of AD pathology and astrogliosis may serve as markers of future brain atrophy and cognitive decline.

Association of plasma biomarkers with imaging markers of brain atrophy and white matter disease across three neurodegenerative diseases and cerebrovascular disease

AbstractBackgroundIt is necessary to better understand the value of plasma biomarkers in reflecting ongoing neurodegenerative processes before widespread use as diagnostic and prognostic tools in specialized clinics and as markers of disease progression in trials. Herein, we investigate their association with imaging markers of brain atrophy and white matter disease across three common neurodegenerative diseases and cerebrovascular disease.MethodPatients from the curated multi‐site Ontario Neurodegenerative Disease Research Initiative (ONDRI) were included in this study, classified by diagnostic group: Alzheimer’s disease/Mild cognitive impairment (AD/MCI, n = 126, age = 71.0±8.2, 55%M), frontotemporal dementia (FTD, n = 53, age = 67.8±7.1, 64%M), Parkinson’s disease (PD, n = 140, age = 67.9±6.3, 78%M) and cerebrovascular disease (CVD, n = 161, age = 69.2±7.4, 68%M). Plasma concentrations of Aβ40 and Aβ42 (Aβ42/40 ratio), glial fibrillary acidic protein (GFAP), neurofilament light (NfL) and phosphorylated‐tau181 (p‐tau181) were measured using high‐sensitivity Simoa assays. Volumes of regional grey matter, ventricular cerebrospinal fluid, white matter hyperintensities, perivascular spaces, lacunes and strokes were extracted using the semi‐automated SABRE pipeline on 3T structural MRI sequences harmonized across sites. Fractions of supratentorial total intracranial volume were used when appropriate. Linear regression models controlling for age and sex were used to test the association between plasma biomarkers and MRI variables in each group separately.ResultIn AD/MCI, higher levels of GFAP, NfL and p‐tau181 were all associated with extensive grey matter atrophy, ventricular expansion and, excluding p‐tau181, with increased white matter hyperintensities. In FTD, increased Aβ42/40 ratio was associated with frontal grey matter atrophy, and higher levels of NfL were associated with ventricular expansion. In PD, higher levels of NfL were associated with frontal, temporal and hippocampal grey matter atrophy. In CVD, higher levels of GFAP and NfL were associated with temporal and subcortical grey matter atrophy and ventricular expansion. Higher levels of GFAP were also associated with enlarged perivascular spaces, while higher levels of NfL were associated with increased lacunes. Finally, still in CVD, higher levels of GFAP and p‐tau181 were associated with increased stroke volumes.ConclusionExcluding Aβ42/40, plasma biomarkers appear to reflect various levels of brain atrophy in all neurodegenerative diseases studied, but reflect markers of white matter disease only in AD/MCI and CVD.

Physical activity of mice on dietary sulfur amino acid restriction is influenced by age of diet initiation and biological sex

Please use the attached pdf file for corrections.Sulfur amino acid restriction (SAAR)—the reduction of methionine and cysteine concentrations either in the diet or by genetic manipulation—promotes health span and extends lifespan, but its effects on physical activity remain unclear. We investigated whether age of diet initiation and biological sex could influence physical activity in mice fed either a control diet (CF, 0.86% methionine w/w) or SAAR (0.12% methionine w/w). Quadriceps femoris muscle mass is smaller in SAAR than in CF mice. Young mice fed a chronic SAAR diet at 8 weeks of age exhibited improved wire hang and running wheel activities compared to young CF mice, while aged mice showed comparable results. The effects of chronic SAAR on physical activity was mildly influenced by sex as observed in middle-aged male SAAR mice who showed minor improvements than CF males while middle-aged females displayed no discernible effects. Muscle mass is minimally affected by changes in markers of protein synthesis, autophagy and atrophy. Improvements to physical activity in young SAAR mice could be partially attributed to increased skeletal muscle mitochondrial activity. Furthermore, SAAR in C2C12 myotubes increased citrate synthase protein expression and enhanced succinyl dehydrogenase enzyme activity compared to CF myotubes. Overall, our data reveal that SAAR can improve mouse physical activity without compromising muscle proteostasis. This is partially due to enhanced mitochondrial activity, but the effects are influenced by age of diet initiation and sex.

LOCAL AND SYSTEMIC MEDIATORS OF SKELETAL MUSCLE WASTING IN HUMANS FOLLOWING ACUTE TRAUMA

AbstractIntroductionSkeletal muscle wasting is an important clinical issue following acute traumatic injury, and can delay recovery and cause permanent functional disability particularly in the elderly. However, the fundamental mechanisms involved in trauma-induced muscle wasting remain poorly defined and therapeutic interventions are limited.ObjectivesTo characterise local and systemic mediators of skeletal muscle wasting in elderly patients following acute trauma.MethodsExperiments were approved by a local NHS Research Ethics Committee and all participants provided written informed consent. Vastus lateralis biopsies and serum samples were taken from human male and female patients shortly after acute trauma injury in lower limbs (n=6; mean age 78.7±4.4 y) and compared to age-matched controls (n=6; mean age 72.6±6.3 y). Atrogenes and upstream regulators (MuRF1; MAFbx; IL6, TNFα, PGC-1α) mRNA expression was assessed in muscle samples via RT-qPCR. Serum profiling of inflammatory markers (e.g. IL6, TNFα, IL1β) was further performed via multiplex assays. To determine whether systemic factors induced by trauma directly affect muscle phenotype, differentiated primary human myotubes were treated in vitro with serum from controls or trauma patients (pooled; n=3 each) in the final 24 hours of differentiation. Cells were then fixed, stained for myogenin and imaged to determine minimum ferret diameter. Statistical significance was determined at P&lt;0.05.ResultsThere was an increase in skeletal muscle mRNA expression for E3 ligase MAFbx and inflammatory cytokine IL-6 (4.6 and 21.5-fold respectively; P&lt;0.05) in trauma patients compared to controls. Expression of myogenic determination factor MyoD and regulator of mitochondrial biogenesis PGC-1α was lower in muscle of trauma patients vs controls (0.5 and 0.39-fold respectively; P&lt;0.05). In serum, trauma patients showed increased concentrations of circulating pro-inflammatory cytokines IL-6 (14.5 vs. 0.3 pg/ml; P&lt;0.05) and IL-16 (182.7 vs. 85.2 pg/ml; P&lt;0.05) compared to controls. Primary myotube experiments revealed serum from trauma patients induced atrophy (32% decrease in diameter) compared to control serum-treated cells (P&lt;0.001).ConclusionSkeletal muscle from patients following acute trauma injury showed greater expression of atrophy and inflammatory markers. Trauma patient serum exhibited higher circulating pro-inflammatory cytokine concentrations. Primary human myotubes treated with serum from trauma patients showed significant atrophy compared to healthy serum-treated controls. We speculate a mechanism(s) acting via circulating factors may contribute to skeletal muscle pathology following acute trauma.Declaration of Interest(b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Fuzhuan brick tea extract ameliorates obesity-induced skeletal muscle atrophy by alleviating mitochondrial dysfunction in mice

Fuzhuan brick tea (FBT) is a post-fermented tea fermented by the fungus Eurotium cristatum and is mainly produced in Hunan Province, China. Our previous study revealed that FBT extract prevents obesity by increasing energy expenditure and mitochondrial content in mice. Therefore, in this study, we hypothesized that FBT extract could be effective in alleviating obesity-induced muscle atrophy by addressing mitochondrial dysfunction, and aimed to explore the underlying molecular mechanism of FBT extract in high-fat diet-induced obese mice. FBT extract increased skeletal muscle weight and size, myosin heavy chain isoforms, and muscle performance in obese mice. Additionally, FBT extract reduced obesity-induced intramuscular lipids, skeletal muscle inflammation, and the expression of skeletal muscle atrophy markers, and increased the expression of fibronectin type III domain-containing protein 5 in skeletal muscles. Obesity-induced skeletal muscle mitochondrial dysfunction was improved by FBT extract as analyzed through mitochondrial morphology, fatty acid oxidation, respiratory chain complexes, and mitochondrial dynamics and biogenesis. Epigallocatechin, a major bioactive compound in FBT extract, attenuated palmitic acid-induced muscle atrophy by regulating mitochondrial functions in C2C12 cells. In conclusion, FBT extract may prevent obesity-induced muscle atrophy by alleviating mitochondrial dysfunction in mice.

STAREE-Mind Imaging Study: a randomised placebo-controlled trial of atorvastatin for prevention of cerebrovascular decline and neurodegeneration in older individuals

IntroductionCerebrovascular disease and neurodegeneration are causes of cognitive decline and dementia, for which primary prevention options are currently lacking. Statins are well-tolerated and widely available medications that potentially have neuroprotective...

Disease progression model anchored around clinical diagnosis in longitudinal cohorts: example of Alzheimer’s disease and related dementia

BackgroundAlzheimer’s disease and related dementia (ADRD) are characterized by multiple and progressive anatomo-clinical changes including accumulation of abnormal proteins in the brain, brain atrophy and severe cognitive impairment. Understanding the sequence and timing of these changes is of primary importance to gain insight into the disease natural history and ultimately allow earlier diagnosis. Yet, modeling changes over disease course from cohort data is challenging as the usual timescales (time since inclusion, chronological age) are inappropriate and time-to-clinical diagnosis is available on small subsamples of participants with short follow-up durations prior to diagnosis. One solution to circumvent this challenge is to define the disease time as a latent variable.MethodsWe developed a multivariate mixed model approach that realigns individual trajectories into the latent disease time to describe disease progression. In contrast with the existing literature, our methodology exploits the clinical diagnosis information as a partially observed and approximate reference to guide the estimation of the latent disease time. The model estimation was carried out in the Bayesian Framework using Stan. We applied the methodology to the MEMENTO study, a French multicentric clinic-based cohort of 2186 participants with 5-year intensive follow-up. Repeated measures of 12 ADRD markers stemmed from cerebrospinal fluid (CSF), brain imaging and cognitive tests were analyzed.ResultsThe estimated latent disease time spanned over twenty years before the clinical diagnosis. Considering the profile of a woman aged 70 with a high level of education and APOE4 carrier (the main genetic risk factor for ADRD), CSF markers of tau proteins accumulation preceded markers of brain atrophy by 5 years and cognitive decline by 10 years. However we observed that individual characteristics could substantially modify the sequence and timing of these changes, in particular for CSF level of Abeta _{42}.ConclusionBy leveraging the available clinical diagnosis timing information, our disease progression model does not only realign trajectories into the most homogeneous way. It accounts for the inherent residual inter-individual variability in dementia progression to describe the long-term anatomo-clinical degradations according to the years preceding clinical diagnosis, and to provide clinically meaningful information on the sequence of events.Trial registrationclinicaltrials.gov, NCT01926249. Registered on 16 August 2013.

Abstract P232: New Anti-contractile Effect Of Skeletal Muscle Is Lost In Hypertension

Since the discovery of the anti-contractile effect of perivascular adipose tissue (PVAT), it has been established that it has a crucial role in vascular function and diseases, including hypertension. However, PVAT has a minimal role in arteries surrounded by skeletal muscles (SM) compared to other vessels. During physical exercise, SM releases several factors ("myokines") that can modulate blood flow, but it is unclear if SM directly controls vascular tone in physiological conditions. The type of SM, glycolytic or oxidative, may also affect vascular dynamics. We hypothesized that SM exhibits an anti-contractile effect crucial for vascular function, which is lost in hypertension. Femoral (FA) and carotid (CA) arteries, adjacent to glycolytic and oxidative SM, respectively, from male and female SHR and Wistar (W) (12-weeks old) rats were mounted in a wire myograph in the absence (-SM) or presence (+SM) of attached or de-attached SM. Concentration-response curves (1nM-100μM) to serotonin (5-HT), phenylephrine (Phe), and thromboxane A2 analog (U46619) were performed. The presence of SM reduced contraction in FA from male (AUC 5-HT: -SM: 442±1 vs. +SM 339±2; p&gt;0.05) and female W rats (AUC: 5-HT: -SM 258.7 ± 18.5 vs. +SM 277±21; p&gt;0.05). Similarly, SM-induced anti-contractile effects were observed in Phe and U46619 curves and in de-attached SM. The anti-contractile effect was absent in W rats CA (AUC: 5-HT: Male: -SM 270±19 vs. +SM 257 ± 25; Female: -SM 250±35 vs. +SM 258±32). Lactate dehydrogenase inhibitor (GSK2837808A, 10nM) abolished the SM anti-contractile effect. In SHR, this anti-contractile effect in FA was not observed (AUC: 5-HT: -SM 103±27 vs. +SM 94±25). FA from SHR showed hypo-contractility to 5-HT (32%) and increased smoothelin expression, an atrophy marker, when measured by Western blot (AU: FA: W: 22861±4504 vs. SHR: 6065±1026; p&gt;0.05). Tests of plantarflexion were performed in vivo to assess SM function. SHR showed a reduction in tetanic contraction (27%), isometric twitch force (27%), and fatigue (22%). These data reveal a new anti-contractile effect of glycolytic SM mediated by lactate and lost in hypertension. Therefore, paracrine and endocrine factors from SM represent a new frontier of vascular physiology research.

Computer-Based Diagnosis of Celiac Disease by Quantitative Processing of Duodenal Endoscopy Images.

Celiac disease (CD) is a lifelong chronic autoimmune systemic disease that primarily affects the small bowel of genetically susceptible individuals. The diagnostics of adult CD currently rely on specific serology and the histological assessment of duodenal mucosa on samples taken by upper digestive endoscopy. Because of several pitfalls associated with duodenal biopsy sampling and histopathology, and considering the pediatric no-biopsy diagnostic criteria, a biopsy-avoiding strategy has been proposed for adult CD diagnosis also. Several endoscopic changes have been reported in the duodenum of CD patients, as markers of villous atrophy (VA), with good correlation with serology. In this setting, an opportunity lies in the automated detection of these endoscopic markers, during routine endoscopy examinations, as potential case-finding of unsuspected CD. We collected duodenal endoscopy images from 18 CD newly diagnosed CD patients and 16 non-CD controls and applied machine learning (ML) and deep learning (DL) algorithms on image patches for the detection of VA. Using histology as standard, high diagnostic accuracy was seen for all algorithms tested, with the layered convolutional neural network (CNN) having the best performance, with 99.67% sensitivity and 98.07% positive predictive value. In this pilot study, we provide an accurate algorithm for automated detection of mucosal changes associated with VA in CD patients, compared to normally appearing non-atrophic mucosa in non-CD controls, using histology as a reference.

Cortical atrophy on baseline computed tomography imaging predicts clinical outcome in patients undergoing endovascular treatment for acute ischemic stroke

ObjectiveMultiple variables beyond the extent of recanalization can impact the clinical outcome after acute ischemic stroke due to large vessel occlusions. Here, we assessed the influence of small vessel disease and cortical atrophy on clinical outcome using native cranial computed tomography (NCCT) in a large single-center cohort.MethodsA total of 1103 consecutive patients who underwent endovascular treatment (EVT) due to occlusion of the middle cerebral artery territory were included. NCCT data were visually assessed for established markers of age-related white matter changes (ARWMC) and brain atrophy. All images were evaluated separately by two readers to assess the inter-observer variability. Regression and machine learning models were built to determine the predictive relevance of ARWMC and atrophy in the presence of important baseline clinical and imaging metrics.ResultsPatients with favorable outcome presented lower values for all measured metrics of pre-existing brain deterioration (p < 0.001). Both ARWMC (p < 0.05) and cortical atrophy (p < 0.001) were independent predictors of clinical outcome at 90 days when controlled for confounders in both regression analyses and led to a minor improvement of prediction accuracy in machine learning models (p < 0.001), with atrophy among the top-5 predictors.ConclusionNCCT-based cortical atrophy and ARWMC scores on NCCT were strong and independent predictors of clinical outcome after EVT.Clinical relevance statementVisual assessment of cortical atrophy and age-related white matter changes on CT could improve the prediction of clinical outcome after thrombectomy in machine learning models which may be integrated into existing clinical routines and facilitate patient selection.Key Points• Cortical atrophy and age-related white matter changes were quantified using CT-based visual scores.• Atrophy and age-related white matter change scores independently predicted clinical outcome after mechanical thrombectomy and improved machine learning–based prediction models.• Both scores could easily be integrated into existing clinical routines and prediction models.

Association of spermidine blood levels with microstructure of sleep—implications from a population-based study

Deteriorations in slow wave sleep (SWS) have been linked to brain aging and Alzheimer’s disease (AD), possibly due to its key role in clearance of amyloid-beta and tau (Aß/tau), two pathogenic hallmarks of AD. Spermidine administration has been shown to improve sleep quality in animal models. So far, the association between spermidine levels in humans and parameters of SWS physiology are unknown but may be valuable for therapeutic strategies. Data from 216 participants (age range 50–81 years) of the population-based Study of Health in Pomerania TREND were included in our analysis. We investigated associations between spermidine plasma levels, key parameters of sleep macroarchitecture and microarchitecture that were previously associated with AD pathology, and brain health measured via a marker of structural brain atrophy (AD score). Higher spermidine levels were significantly associated with lower coupling between slow oscillations and spindle activity. No association was evident for SWS, slow oscillatory, and spindle activity throughout non-rapid eye movement sleep. Furthermore, elevated spermidine blood levels were significantly associated with a higher AD score, while sleep markers revealed no association with AD score. The association between higher spermidine levels and brain health was not mediated by coupling between slow oscillations and spindle activity. We report that higher spermidine blood levels are associated not only with deteriorated brain health but also with less advantageous markers of sleep quality in older adults. Future studies need to evaluate whether sleep, spermidine, and Aß/tau deposition are interrelated and whether sleep may play a mediating role.

Abstract P2144: Irisin, An Exercise-induced Myokine, Exhibits Protective Effects In Glucocorticoid-induced Cardiac Muscle Dysfunctions

Myocardial infarction caused by pharmacological substances, such as anti-inflammatory drugs, is a serious adverse drug effect in the cardiovascular system that often causes heart failure. Dexamethasone (DEX), a synthetic glucocorticoid, is commonly used as potent anti-inflammatory and immunosuppressive drugs, but is classified as one of the prime suspects of drug-induced acute myocardial infarction. High dose of DEX increased oxidative stress of the heart, induced myocardial degeneration and cardiomyocyte apoptosis and impaired cardiac contraction. Thus, therapeutic approaches are required to alleviate glucocorticoids-induced cardiotoxicity and prevent DEX-mediated cardiac complications. Exercise-induced secretion of irisin showed the beneficial effects against cardiovascular diseases on energy metabolism, anti-oxidant effects, and decreased inflammation and apoptosis by promoting mitochondria biogenesis, decreasing oxidative stress and inflammatory responses, and regulating intracellular calcium signaling. In this study, we investigate the endocrine effects of muscle-secreted irisin against DEX-induced cardiotoxicity. We engineered anisotropic human induced-pluripotent stem cell-derived cardiomyocyte tissues and designed three experimental groups: control, dex treatment, and dex plus irisin treatment. We then analyze the tissues with qPCR, immunostaining (muscle atrophy markers), contractility assay, and oxygen consumption assay to evaluate the protective effects of irisin on DEX-induced cardiac injury. Injured cardiac tissues showed systolic dysfunction by decreasing oxygen consumption, increasing muscle atrophy marker (MuRF-1), and significantly reducing systolic contractile force, but not diastolic stress. In contrast, these DEX-induced maladaptive responses was alleviated by irisin pretreatment by reducing proteolytic activity and muscle atrophy signaling pathways and promoting mitochondria biogenesis. In conclusion, our micro-physiological system showed the therapeutic effects of irisin against DEX-induced cardiotoxicity.