scholarly journals The caloric restriction fallacy, rodent diet aids and the tumor suppression theory of aging

2021 ◽  
Author(s):  
Alexander Wolf
Keyword(s):  
Life Span ◽  
Caloric Restriction ◽  
Tumor Suppression ◽  
Molecular Mechanisms ◽  
Mouse Strains ◽  
Control Group ◽  
Obese Mouse ◽  
Healthy Weight ◽  
Nicotinamide Mononucleotide ◽  
Theory Of Aging

Understanding the molecular mechanisms of normal aging is a prerequisite to significantly increase human health span. Caloric restriction (CR), which delays aging in most animal models, serves as a yardstick to evaluate interventions extending life span. However, mice given unlimited access to food suffer severe obesity and benefits from CR might be through reducing obesity-associated mortality. Health gains from CR depend on the control mice being gluttonous enough and less obese mouse strains benefit far less from CR. Most pharmacologic interventions reported to mimic CR and increase life span in mice, including resveratrol, rapamycin, nicotinamide mononucleotide and metformin, also reduce mouse body weight. In primates, CR does not delay aging unless the control group is eating enough to suffer from obesity-related disease. Human survival peaks at a BMI achievable without CR. CR mimetics are just diet aids and CR should not be regarded as increasing longevity in healthy weight individuals. Instead, I propose the tumor suppression theory of aging: most phenotypes of aging are the consequence of tumor-suppressive cell senescence that has evolved to limit the tumorigenic potential of clonally expanding cells. A variant of the somatic mutation theory of aging, oncogenic mutations and clonal expansion (opposed to functional impairment) are postulated as the most relevant consequence of somatic mutations. Irreversible cell cycle arrest, accumulating senescent cells, the senescence-associated secretory phenotype and subsequent stem cell depletion eventually cause tissue dysfunction, loss of regeneration and the majority, if not most, phenotypes of aging.

Recent approaches for isolating and culturing mouse bone marrow-derived mesenchymal stromal stem cells

2020 ◽  
Vol 15 ◽  
Author(s):  
Basem M. Abdallah ◽  
Hany M. Khattab
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Molecular Mechanisms ◽  
Replicative Senescence ◽  
Cellular Heterogeneity ◽  
High Yield ◽  
Mouse Strains ◽  
Mouse Bone Marrow ◽  
Differentiation Potential ◽  
Stromal Stem Cells

: The isolation and culture of murine bone marrow-derived mesenchymal stromal stem cells (mBMSCs) have attracted great interest in terms of the pre-clinical applications of stem cells in tissue engineering and regenerative medicine. In addition, culturing mBMSCs is important for studying the molecular mechanisms of bone remodelling using relevant transgenic mice. Several factors have created challenges in the isolation and high-yield expansion of homogenous mBMSCs; these factors include low frequencies of bone marrow-derived mesenchymal stromal stem cells (BMSCs) in bone marrow, variation among inbred mouse strains, contamination with haematopoietic progenitor cells (HPCs), the replicative senescence phenotype and cellular heterogeneity. In this review, we provide an overview of nearly all protocols used for isolating and culturing mBMSCs with the aim of clarifying the most important guidelines for culturing highly purified mBMSC populations retaining in vitro and in vivo differentiation potential.

scholarly journals The Integrated RNA Landscape of Renal Preconditioning against Ischemia-Reperfusion Injury

2020 ◽  
Vol 31 (4) ◽  
pp. 716-730 ◽  
Author(s):  
Marc Johnsen ◽  
Torsten Kubacki ◽  
Assa Yeroslaviz ◽  
Martin Richard Späth ◽  
Jannis Mörsdorf ◽  
...  
Keyword(s):  
Gene Expression ◽  
Reperfusion Injury ◽  
Caloric Restriction ◽  
Molecular Mechanisms ◽  
Target Genes ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Hypoxic Preconditioning ◽  
Preventive Strategies ◽  
Gene Expression Signatures

BackgroundAlthough AKI lacks effective therapeutic approaches, preventive strategies using preconditioning protocols, including caloric restriction and hypoxic preconditioning, have been shown to prevent injury in animal models. A better understanding of the molecular mechanisms that underlie the enhanced resistance to AKI conferred by such approaches is needed to facilitate clinical use. We hypothesized that these preconditioning strategies use similar pathways to augment cellular stress resistance.MethodsTo identify genes and pathways shared by caloric restriction and hypoxic preconditioning, we used RNA-sequencing transcriptome profiling to compare the transcriptional response with both modes of preconditioning in mice before and after renal ischemia-reperfusion injury.ResultsThe gene expression signatures induced by both preconditioning strategies involve distinct common genes and pathways that overlap significantly with the transcriptional changes observed after ischemia-reperfusion injury. These changes primarily affect oxidation-reduction processes and have a major effect on mitochondrial processes. We found that 16 of the genes differentially regulated by both modes of preconditioning were strongly correlated with clinical outcome; most of these genes had not previously been directly linked to AKI.ConclusionsThis comparative analysis of the gene expression signatures in preconditioning strategies shows overlapping patterns in caloric restriction and hypoxic preconditioning, pointing toward common molecular mechanisms. Our analysis identified a limited set of target genes not previously known to be associated with AKI; further study of their potential to provide the basis for novel preventive strategies is warranted. To allow for optimal interactive usability of the data by the kidney research community, we provide an online interface for user-defined interrogation of the gene expression datasets (http://shiny.cecad.uni-koeln.de:3838/IRaP/).

scholarly journals Molecular mechanisms of Zika virus teratogenesis from animal studies: a systematic review protocol

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Gabriela Elis Wachholz ◽  
Julia do Amaral Gomes ◽  
Juliano André Boquett ◽  
Fernanda Sales Luiz Vianna ◽  
Lavínia Schuler-Faccini ◽  
...  
Keyword(s):  
Systematic Review ◽  
Animal Models ◽  
Zika Virus ◽  
Methodological Quality ◽  
Molecular Mechanisms ◽  
Grey Literature ◽  
Standard Form ◽  
Teratogenic Effect ◽  
Control Group

Abstract Background Due to the diversity of studies in animal models reporting that molecular mechanisms are involved in the teratogenic effect of the Zika virus (ZIKV), the objective of the present study is to evaluate the methodological quality of these studies, as well as to demonstrate which genes and which molecular pathways are affected by ZIKV in different animal models. Methods This search will be performed in four databases: PubMed/MEDLINE, EMBASE, Web of Science, and Scopus, as well as in the grey literature. The studies selection process will be reported through the PRISMA Statement diagram model. All studies describing the molecular mechanisms possibly involved in the development of malformations caused by embryonic/fetal ZIKV exposure in animal models with an appropriate control group and methodology will be included (including, for instance, randomized and non-randomized studies). All animals used as experimental models for ZIKV teratogenesis may be included as long as exposure to the virus occurred during the embryonic/fetal period. From the selected studies, data will be extracted using a previously prepared standard form. Bias risk evaluation will be conducted following the SYRCLE’s Risk of Bias tool. All data obtained will be tabulated and organized by outcomes (morphological and molecular). Discussion With the proposed systematic review, we expect to present results about the methodological quality of the published studies with animal models that investigated the molecular mechanisms involved in the teratogenic effect of ZIKV, as well as to show the studies with greater reliability. Systematic review registration PROSPERO CRD42019157316

scholarly journals Ultrafine particles altered gut microbial population and metabolic profiles in a sex-specific manner in an obese mouse model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kundi Yang ◽  
Mengyang Xu ◽  
Jingyi Cao ◽  
Qi Zhu ◽  
Monica Rahman ◽  
...  
Keyword(s):  
Ultrafine Particles ◽  
Microbial Population ◽  
Phosphate Buffer Solution ◽  
Biodiesel Fuel ◽  
Control Group ◽  
Obese Mouse ◽  
Rrna Gene ◽  
Obese Mice ◽  
Microbial Composition ◽  
Increased Risk

AbstractEmerging evidence has highlighted the connection between exposure to air pollution and the increased risk of obesity, metabolic syndrome, and comorbidities. Given the recent interest in studying the effects of ultrafine particle (UFP) on the health of obese individuals, this study examined the effects of gastrointestinal UFP exposure on gut microbial composition and metabolic function using an in vivo murine model of obesity in both sexes. UFPs generated from light-duty diesel engine combustion of petrodiesel (B0) and a petrodiesel/biodiesel fuel blend (80:20 v/v, B20) were administered orally. Multi-omics approaches, including liquid chromatography–mass spectrometry (LC–MS) based targeted metabolomics and 16S rRNA gene sequence analysis, semi-quantitatively compared the effects of 10-day UFP exposures on obese C57B6 mouse gut microbial population, changes in diversity and community function compared to a phosphate buffer solution (PBS) control group. Our results show that sex-specific differences in the gut microbial population in response to UFP exposure can be observed, as UFPs appear to have a differential impact on several bacterial families in males and females. Meanwhile, the alteration of seventy-five metabolites from the gut microbial metabolome varied significantly (ANOVA p < 0.05) across the PBS control, B0, and B20 groups. Multivariate analyses revealed that the fuel-type specific disruption to the microbial metabolome was observed in both sexes, with stronger disruptive effects found in females in comparison to male obese mice. Metabolic signatures of bacterial cellular oxidative stress, such as the decreased concentration of nucleotides and lipids and increased concentrations of carbohydrate, energy, and vitamin metabolites were detected. Furthermore, blood metabolites from the obese mice were differentially affected by the fuel types used to generate the UFPs (B0 vs. B20).

scholarly journals Improved response of human gingival fibroblasts to titanium coated with micro-/nano-structured tantalum

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Chu-nan Zhang ◽  
Lin-yi Zhou ◽  
Shu-jiao Qian ◽  
Ying-xin Gu ◽  
Jun-yu Shi ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Underlying Mechanism ◽  
Cell Number ◽  
Human Gingival Fibroblasts ◽  
Superior Performance ◽  
Control Group ◽  
Human Gingival Fibroblast ◽  
Gingival Fibroblast ◽  
Gingival Fibroblasts ◽  
Integrin Β1

Abstract Objectives This study aims to evaluate the ability of tantalum-coated titanium to improve human gingival fibroblasts’ adhesion, viability, proliferation, migration performance, and the potential molecular mechanisms. Materials and methods Titanium plates were divided into two groups: (1) no coating (Ti, control), (2) Tantalum-coated titanium (Ta-coated Ti). All samples were characterized by scanning electronic microscopy, surface roughness, and hydrophilicity. Fibroblasts’ performance were analyzed by attached cell number at 1 h, 4 h, and 24 h, morphology at 1 h and 4 h, viability at 1 day, 3 days, 5 days, and 7 days, recovery after wounding at 6 h, 12 h, and 24 h. RT-PCR, western blot were applied to detect attachment-related genes’ expression and protein synthesis at 4 h and 24 h. Student’s t test was used for statistical analysis. Results Tantalum-coated titanium demonstrates a layer of homogeneously distributed nano-grains with mean diameter of 25.98 (± 14.75) nm. It was found that after tantalum deposition, human gingival fibroblasts (HGFs) adhesion, viability, proliferation, and migration were promoted in comparison to the control group. An upregulated level of Integrin β1 and FAK signaling was also detected, which might be the underlying mechanism. Conclusion In the present study, adhesion, viability, proliferation, migration of human gingival fibroblasts are promoted on tantalum-coated titanium, upregulated integrin β1 and FAK might contribute to its superior performance, indicating tantalum coating can be applied in transmucosal part of dental implant. Clinical significance Tantalum deposition on titanium surfaces can promote human gingival fibroblast adhesion, accordingly forming a well-organized soft tissue sealing and may contribute to a successful osseointegration.

scholarly journals Cellular Response against Oxidative Stress, a Novel Insight into Lupus Nephritis Pathogenesis

2021 ◽  
Vol 11 (8) ◽  
pp. 693
Author(s):  
Corina Daniela Ene ◽  
Simona Roxana Georgescu ◽  
Mircea Tampa ◽  
Clara Matei ◽  
Cristina Iulia Mitran ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Lupus Nephritis ◽  
Cellular Response ◽  
Molecular Mechanisms ◽  
Control Group ◽  
Dna Repair Mechanisms ◽  
Glycation End Products ◽  
Repair Mechanisms ◽  
Low Levels ◽  
Defective Dna Repair

The interaction of reactive oxygen species (ROS) with lipids, proteins, nucleic acids and hydrocarbonates promotes acute and chronic tissue damage, mediates immunomodulation and triggers autoimmunity in systemic lupus erythematous (SLE) patients. The aim of the study was to determine the pathophysiological mechanisms of the oxidative stress-related damage and molecular mechanisms to counteract oxidative stimuli in lupus nephritis. Our study included 38 SLE patients with lupus nephritis (LN group), 44 SLE patients without renal impairment (non-LN group) and 40 healthy volunteers as control group. In the present paper, we evaluated serum lipid peroxidation, DNA oxidation, oxidized proteins, carbohydrate oxidation, and endogenous protective systems. We detected defective DNA repair mechanisms via 8-oxoguanine-DNA-glycosylase (OGG1), the reduced regulatory effect of soluble receptor for advanced glycation end products (sRAGE) in the activation of AGE-RAGE axis, low levels of thiols, disulphide bonds formation and high nitrotyrosination in lupus nephritis. All these data help us to identify more molecular mechanisms to counteract oxidative stress in LN that could permit a more precise assessment of disease prognosis, as well as developing new therapeutic targets.

scholarly journals Changes on proteomic and metabolomic profile in serum of mice induced by chronic exposure to tramadol

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shukun Jiang ◽  
Guojie Liu ◽  
Huiya Yuan ◽  
Enyu Xu ◽  
Wei Xia ◽  
...  
Keyword(s):  
Chronic Exposure ◽  
Molecular Mechanisms ◽  
Fatty Acid Biosynthesis ◽  
Serum Proteins ◽  
Enzyme Inhibitor ◽  
Bile Secretion ◽  
Control Group ◽  
Protein Digestion ◽  
Metabolomic Profile ◽  
Apolipoprotein C

AbstractTramadol is an opioid used as an analgesic for treating moderate or severe pain. The long-term use of tramadol can induce several adverse effects. The toxicological mechanism of tramadol abuse is unclear. Limited literature available indicates the change of proteomic profile after chronic exposure to tramadol. In this study, we analyzed the proteomic and metabolomic profile by TMT-labeled quantitative proteomics and untargeted metabolomics between the tramadol and the control group. Proteomic analysis revealed 31 differential expressed serum proteins (9 increased and 22 decreased) in tramadol-treated mice (oral, 50 mg/kg, 5 weeks) as compared with the control ones. Bioinformatics analysis showed that the dysregulated proteins mainly included: enzyme inhibitor-associated proteins (i.e. apolipoprotein C-III (Apoc-III), alpha-1-antitrypsin 1–2 (Serpina 1b), apolipoprotein C-II (Apoc-II), plasma protease C1 inhibitor, inter-alpha-trypsin inhibitor heavy chain H3 (itih3)); mitochondria-related proteins (i.e. 14-3-3 protein zeta/delta (YWHAZ)); cytoskeleton proteins (i.e. tubulin alpha-4A chain (TUBA4A), vinculin (Vcl)). And we found that the differential expressed proteins mainly involved in the pathway of the protein digestion and absorption. Metabolomics analysis revealed that differential expressed metabolites mainly involved in protein ingestion and absorption, fatty acid biosynthesis, steroid hormone biosynthesis and bile secretion. Our overall findings revealed that chronic exposure to tramadol changed the proteomic and metabolomic profile of mice. Moreover, integrated proteomic and metabolomic revealed that the protein digestion and absorption is the common enrichment KEGG pathway. Thus, the combination of proteomics and metabolomics opens new avenues for the research of the molecular mechanisms of tramadol toxicity.

scholarly journals Application of Clinical Decision Support System to Assist Breast Cancer Patients with Lifestyle Modifications during the COVID-19 Pandemic: A Randomised Controlled Trial

Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 2115
Author(s):  
Panos Papandreou ◽  
Aristea Gioxari ◽  
Frantzeska Nimee ◽  
Maria Skouroliakou
Keyword(s):  
Breast Cancer ◽  
Quality Of Life ◽  
Decision Support ◽  
Clinical Decision Support ◽  
Clinical Decision ◽  
Control Group ◽  
Healthy Weight ◽  
Lifestyle Modifications ◽  
Randomised Controlled

Clinical decision support systems (CDSS) are data aggregation tools based on computer technology that assist clinicians to promote healthy weight management and prevention of cardiovascular diseases. We carried out a randomised controlled 3-month trial to implement lifestyle modifications in breast cancer (BC) patients by means of CDSS during the COVID-19 pandemic. In total, 55 BC women at stages I-IIIA were enrolled. They were randomly assigned either to Control group, receiving general lifestyle advice (n = 28) or the CDSS group (n = 27), to whom the CDSS provided personalised dietary plans based on the Mediterranean diet (MD) together with physical activity guidelines. Food data, anthropometry, blood markers and quality of life were evaluated. At 3 months, higher adherence to MD was recorded in the CDSS group, accompanied by lower body weight (kg) and body fat mass percentage compared to control (p < 0.001). In the CDSS arm, global health/quality of life was significantly improved at the trial endpoint (p < 0.05). Fasting blood glucose and lipid levels (i.e., cholesterol, LDL, triacylglycerols) of the CDSS arm remained unchanged (p > 0.05) but were elevated in the control arm at 3 months (p < 0.05). In conclusion, CDSS could be a promising tool to assist BC patients with lifestyle modifications during the COVID-19 pandemic.

scholarly journals The potential renal toxicity of silver nanoparticles after repeated oral exposure and its underlying mechanisms

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Hamed Nosrati ◽  
Manijeh Hamzepoor ◽  
Maryam Sohrabi ◽  
Massoud Saidijam ◽  
Mohammad Javad Assari ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Molecular Mechanisms ◽  
Renal Toxicity ◽  
Periodic Acid ◽  
Critical Role ◽  
Oral Exposure ◽  
Control Group ◽  
Rt Pcr ◽  
Periodic Acid Schiff

Abstract Background Silver nanoparticles (AgNPs) can accumulate in various organs after oral exposure. The main objective of the current study is to evaluate the renal toxicity induced by AgNPs after repeated oral exposure and to determine the relevant molecular mechanisms. Methods In this study, 40 male Wistar rats were treated with solutions containing 30, 125, 300, and 700 mg/kg of AgNPs. After 28 days of exposure, histopathological changes were assessed using hematoxylin-eosin (H&E), Masson’s trichrome, and periodic acid-Schiff (PAS) staining. Apoptosis was quantified by TUNEL and immunohistochemistry of caspase-3, and the level of expression of the mRNAs of growth factors was determined using RT-PCR. Results Histopathologic examination revealed degenerative changes in the glomeruli, loss of tubular architecture, loss of brush border, and interrupted tubular basal laminae. These changes were more noticeable in groups treated with 30 and 125 mg/kg. The collagen intensity increased in the group treated with 30 mg/kg in both the cortex and the medulla. Apoptosis was much more evident in middle-dose groups (i.e., 125 and 300 mg/kg). The results of RT-PCR indicated that Bcl-2 and Bax mRNAs upregulated in the treated groups (p < 0.05). Moreover, the data related to EGF, TNF-α, and TGF-β1 revealed that AgNPs induced significant changes in gene expression in the groups treated with 30 and 700 mg/kg compared to the control group. Conclusion Our observations showed that AgNPs played a critical role in in vivo renal toxicity.

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