scholarly journals Immunosenescence of Polymorphonuclear Neutrophils

2010 ◽  
Vol 10 ◽  
pp. 145-160 ◽  
Author(s):  
Inga Wessels ◽  
Judith Jansen ◽  
Lothar Rink ◽  
Peter Uciechowski

All immune cells are affected by aging, contributing to the high susceptibility to infections and increased mortality observed in the elderly. The effect of aging on cells of the adaptive immune system is well documented. In contrast, knowledge concerning age-related defects of polymorphonuclear neutrophils (PMN) is limited. During the past decade, it has become evident that in addition to their traditional role as phagocytes, neutrophils are able to secrete a wide array of immunomodulating molecules. Their importance is underlined by the finding that genetic defects that lead to neutropenia increase susceptibility to infections. Whereas there is consistence about the constant circulating number of PMN throughout aging, the abilities of tissue infiltration, phagocytosis, and oxidative burst of PMN from aged donors are discussed controversially. Furthermore, there are numerous discrepancies betweenin vivoandin vitroresults, as well as between results for murine and human PMN. Most of the reported functional changes can be explained by defective signaling pathways, but further research is required to get a detailed insight into the underlying molecular mechanisms. This could form the basis for drug development in order to prevent or treat age-related diseases, and thus to unburden the public health systems.

1998 ◽  
Vol 111 (6) ◽  
pp. 759-767
Author(s):  
G. Herrmann ◽  
P. Brenneisen ◽  
M. Wlaschek ◽  
J. Wenk ◽  
K. Faisst ◽  
...  

Premature aging of the skin is a prominent side effect of psoralen photoactivation, a treatment used widely for various skin disorders. The molecular mechanisms underlying premature aging upon psoralen photoactivation are as yet unknown. Here we show that treatment of fibroblasts with 8-methoxypsoralen (8-MOP) and subsequent ultraviolet A (UVA) irradiation resulted in a permanent switch of mitotic to stably postmitotic fibroblasts which acquired a high level of de novo expression of SA-beta-galactosidase, a marker for fibroblast senescence in vitro and in vivo. A single exposure of fibroblasts to 8-MOP/UVA resulted in a 5.8-fold up-regulation of two matrix-degrading enzymes, interstitial collagenase (MMP-1) and stromelysin-1 (MMP-3), over a period of >120 days, while TIMP-1, the major inhibitor of MMP-1 and MMP-3, was only slightly induced. This imbalance between matrix-degrading metalloproteases and their inhibitor may lead to connective tissue damage, a hallmark of premature aging. Superoxide anion and hydrogen peroxide, but not singlet oxygen, were identified as important intermediates in the downstream signaling pathway leading to these complex fibroblast responses upon psoralen photoactivation. Collectively, the end phenotype induced upon psoralen photoactivation shares several criteria of senescent cells. In the absence of detailed molecular data on what constitutes normal aging, it is difficult to decide whether the changes reported here reflect mechanisms underlying normal cellular aging/senescence or rather produce a mimic of cellular aging/senescence by quite different pathways.


2021 ◽  
Author(s):  
Ran Mei ◽  
Xichun Cui ◽  
Lili Zheng ◽  
Li Jingyi

Abstract Background: Breast cancer (BRCA) is the most common type of women's cancer with a high incidence. The function of gamma-aminobutyric acid A receptor θ subunit (GABRQ) has been studied in other cancers. The results demonstrated that the expression levels of GABRQ were closely associated with tumor prognosis. However, the functions and mechanisms of GABRQ in BRCA remain unclear.Materials and methods: We used the public genome datasets and a tissue microarray (TMA) cohort to analyze the GABRQ expression levels. We performed Immunohistochemistry (IHC) and Western blot to determine GABRQ expression in BRCA cell lines and tissues. Cell proliferation was assessed by EDU assay and colony formation assay. Transwell assay was carried out to investigate the cell invasion ability in vitro and Xenograft nude mouse model was constructed to test the function of GABRQ on tumor growth in vivo. Moreover, we utilized bioinformatic analysis to identify the potential molecular mechanisms mediated by GABRQ modification in BRCA.Results: GABRQ was markedly up-regulated in BRCA tissues, and the expression levels of GABRQ were closely associated with BRCA prognosis. Functional analysis elucidated that knockdown of GABRQ could suppress BRCA cell growth and invasion in vitro, and inhibit tumor development in vivo. Moreover, we found that GABRQ overexpression activated the EMT signaling pathway.Conclusions: These results demonstrated that the function of GABRQ in BRCA progression provided potential prognostic predictors for BRCA patients.


2020 ◽  
Vol 12 ◽  
Author(s):  
Ai Qing Yu ◽  
Jie Wang ◽  
Xiao Jia Zhou ◽  
Ke Yu Chen ◽  
You De Cao ◽  
...  

Cellular senescence is implicated in several lines of aging-related disorders. However, the potential molecular mechanisms by which cellular senescence modulates age-related pathologies remain largely unexplored. Herein, we report that the density of sympathetic fibers (SFs) is significantly elevated in naturally aged mouse tissues and human colon adenoma tissues compared to the SFs densities in the corresponding young mouse tissues and human non-lesion colon tissues. A dorsal root ganglion (DRG)-human diploid fibroblast coculture assay revealed that senescent cells promote the outgrowth of SFs, indicating that the senescent cells induce recruitment of SFs in vitro. Additionally, subcutaneous transplantation of 2BS fibroblasts in nude mice shows that transplanted senescent 2BS fibroblasts promote SFs infiltration. Intra-articular senolytic molecular injection can reduce SFs density and inhibit SFs infiltration caused by senescent cells in osteoarthritis (OA), suggesting senescent cells promote the infiltration of SFs in vivo in aged tissues. Notably, the elevated level of SFs contributes to impaired cognitive function in naturally aged mice, which can be reversed by treatment with propranolol hydrochloride, a non-selective β receptor blocker that inhibits sympathetic nerve activity (SNA) by blocking non-selective β receptors. Additionally, 6-hydroxydopamine (6-OHDA)-induced sympathectomy improved hepatic sympathetic overactivity mediated hepatic steatosis in high fat diet (HFD)-fed APOE knockout mice (APOE−/− mice) by reducing hepatic SNA. Taken together, this study concludes that senescent cell-secreted netrin-1 mediated SFs outgrowth and infiltration, which contributes to aging-related disorders, suggesting that clearing senescent cells or inhibiting SNA is a promising therapeutic strategy for improving sympathetic nervous system (SNS) hyperactivity-induced aging-related pathologies.


2021 ◽  
Vol 8 ◽  
Author(s):  
Delany Rodriguez ◽  
Daryl A. Taketa ◽  
Roopa Madhu ◽  
Susannah Kassmer ◽  
Dinah Loerke ◽  
...  

Vascular diseases affect over 1 billion people worldwide and are highly prevalent among the elderly, due to a progressive deterioration of the structure of vascular cells. Most of our understanding of these age-related cellular changes comes from in vitro studies on human cell lines. Further studies of the mechanisms underlying vascular aging in vivo are needed to provide insight into the pathobiology of age-associated vascular diseases, but are difficult to carry out on vertebrate model organisms. We are studying the effects of aging on the vasculature of the invertebrate chordate, Botryllus schlosseri. This extracorporeal vascular network of Botryllus is transparent and particularly amenable to imaging and manipulation. Here we use a combination of transcriptomics, immunostaining and live-imaging, as well as in vivo pharmacological treatments and regeneration assays to show that morphological, transcriptional, and functional age-associated changes within vascular cells are key hallmarks of aging in B. schlosseri, and occur independent of genotype. We show that age-associated changes in the cytoskeleton and the extracellular matrix reshape vascular cells into a flattened and elongated form and there are major changes in the structure of the basement membrane over time. The vessels narrow, reducing blood flow, and become less responsive to stimuli inducing vascular regression. The extracorporeal vasculature is highly regenerative following injury, and while age does not affect the regeneration potential, newly regenerated vascular cells maintain the same aged phenotype, suggesting that aging of the vasculature is a result of heritable epigenetic changes.


Beverages ◽  
2018 ◽  
Vol 4 (4) ◽  
pp. 96 ◽  
Author(s):  
Paula Silva ◽  
David Vauzour

Alzheimer’s and Parkinson’s diseases are the most common age-related and predominantly idiopathic neurodegenerative disorders of unknown pathogenesis. Although there are both clinical and neuropathological features of these diseases that are different, they also share some common aetiologies, such as protein aggregation, mitochondrial dysfunction, oxidative stress, and neuroinflammation. Epidemiological, in vitro and in vivo evidences suggest an inverse correlation between wine consumption and the incidence of neurodegenerative disorders. Wine benefits are, in large part, attributable to the intake of specific polyphenols, which mediate cell function under both normal and pathological conditions. In this review, we aim to provide an overview of the role that wine consumption plays in delaying neurodegenerative disorders. We discuss animal and in vitro studies in support of these actions and we consider how their biological mechanisms at the cellular level may underpin their physiological effects. Together, these data indicate that polyphenols present in wine may hold neuroprotective potential in delaying the onset of neurodegenerative disorders.


2020 ◽  
Vol 8 (Suppl 2) ◽  
pp. A15.1-A15
Author(s):  
CA Reichel ◽  
L Mittmann ◽  
J Schaubächer ◽  
R Hennel ◽  
G Zuchtriegel ◽  
...  

BackgroundBeyond their well-established role in host defense, neutrophils are increasingly recognized to contribute to the pathogenesis of malignant tumors. Recently, ageing of mature neutrophils in the systemic circulation has been identified to be critical for these immune cells to properly unfold their anti-infectious properties. The role of neutrophil ageing in cancer is still unknown.Material and MethodsEmploying syngeneic mouse models of head and neck squamous cell carcinoma (cell line SCC VII) and breast cancer (cell line 4T1), cytokine expression (by multiplex ELISA), neutrophil trafficking (by multi-channel in vivo microscopy and flow cytometry), and neutrophil function (in vitro assays) were analyzed.ResultsHere, we show that signals released during early tumor growth promote excessive biological ageing of circulating neutrophils as indicated by age-related changes in their molecular repertoire. These events facilitate the accumulation of these highly reactive immune cells in malignant lesions and endow them with potent pro-tumorigenic functions. In particular, excessively aged neutrophils release neutrophil elastase which, in turn, stimulates the proliferation of cancer cells. Counteracting accelerated biological ageing of circulating neutrophils by blocking the chemokine receptor CXCR2 effectively suppressed tumor growth.ConclusionsOur experimental data uncover a potent self-sustaining mechanism of malignant tumors in fostering pro-tumorigenic phenotypic and functional changes in circulating neutrophils, thus supporting tumor progression. Interference with this aberrant process might provide a novel, already pharmacologically targetable strategy for cancer therapy. This study was supported by Deutsche Forschungsgemeinschaft (DFG), Sonderforschungsbereich (SFB) 914.Disclosure InformationC.A. Reichel: None. L. Mittmann: None. J. Schaubächer: None. R. Hennel: None. G. Zuchtriegel: None. M. Canis: None. O. Gires: None. F. Krombach: None. L. Holdt: None. S. Brandau: None. T. Vogl: None. K. Lauber: None. B. Uhl: None.


2016 ◽  
Vol 27 (3) ◽  
pp. 271-281 ◽  
Author(s):  
Mrinmay Chakrabarti ◽  
Arabinda Das ◽  
Supriti Samantaray ◽  
Joshua A. Smith ◽  
Naren L. Banik ◽  
...  

AbstractEstrogen (EST) is a steroid hormone that exhibits several important physiological roles in the human body. During the last few decades, EST has been well recognized as an important neuroprotective agent in a variety of neurological disorders in the central nervous system (CNS), such as spinal cord injury (SCI), traumatic brain injury (TBI), Alzheimer’s disease, and multiple sclerosis. The exact molecular mechanisms of EST-mediated neuroprotection in the CNS remain unclear due to heterogeneity of cell populations that express EST receptors (ERs) in the CNS as well as in the innate and adaptive immune system. Recent investigations suggest that EST protects the CNS from injury by suppressing pro-inflammatory pathways, oxidative stress, and cell death, while promoting neurogenesis, angiogenesis, and neurotrophic support. In this review, we have described the currently known molecular mechanisms of EST-mediated neuroprotection and neuroregeneration in SCI and TBI. At the same time, we have emphasized on the recent in vitro and in vivo findings from our and other laboratories, implying potential clinical benefits of EST in the treatment of SCI and TBI.


2017 ◽  
Vol 26 (9) ◽  
pp. 1520-1529 ◽  
Author(s):  
Payal Ganguly ◽  
Jehan J. El-Jawhari ◽  
Peter V. Giannoudis ◽  
Agata N. Burska ◽  
Frederique Ponchel ◽  
...  

Aging at the cellular level is a complex process resulting from accumulation of various damages leading to functional impairment and a reduced quality of life at the level of the organism. With a rise in the elderly population, the worldwide incidence of osteoporosis (OP) and osteoarthritis (OA) has increased in the past few decades. A decline in the number and “fitness” of mesenchymal stromal cells (MSCs) in the bone marrow (BM) niche has been suggested as one of the factors contributing to bone abnormalities in OP and OA. It is well recognized that MSCs in vitro acquire culture-induced aging features such as gradual telomere shortening, increased numbers of senescent cells, and reduced resistance to oxidative stress as a result of serial population doublings. In contrast, there is only limited evidence that human BM-MSCs “age” similarly in vivo. This review compares the various aspects of in vitro and in vivo MSC aging and suggests how our current knowledge on rejuvenating cultured MSCs could be applied to develop future strategies to target altered bone formation processes in OP and OA.


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