ABT-263 enhanced bacterial phagocytosis of macrophages in aged mouse through Beclin-1-dependent autophagy

Abstract Background Sepsis is a critical challenge for the older adults as the immune function is less responsive by aging. Although cell numbers seem preserved in the older adults, macrophages present age-related function decline, which including reduced chemokines, phagocytosis, and autophagy. ABT-263, an inhibitor of the anti-apoptotic protein Bcl-2, is reported had a senolytic effect which can selectively clear the senescent cells in vivo and rejuvenate the aged tissues. Methods We treated the aged (12–16 months) and young (4–6 months) C57BL/6 mouse with ABT-263, then gave the animals cecal slurry injection to induce sepsis to observe the effect of senolytic compound ABT-263 on the survival rate of sepsis. Additionally, we isolated peritoneal macrophages from the aged mouse to investigate the cell function and molecular mechanism. 3-methyladenine (3-MA), a phosphatidylinositol 3-kinases (PI3K) inhibitor, and rapamycin, an autophagy-enhancer, were used to block or mimic the autophagy, respectively. RT-PCR and Western Blot were used to detect autophagy related gene and protein changes in sepsis. EGFP-expressing E. coli was used as a marker to evaluate the phagocytic ability of macrophages. Results The results showed ABT-263 treatment improved the survival rate of sepsis in the aged mouse which related to autophagy, while blocking the autophagy can eliminate this effect. It is revealed that ABT-263 enhanced the phagocytic ability of the peritoneal macrophages by increasing the Trem-2 receptor. Additionally, ABT-263 blocked the binding of Bcl-2 to Beclin-1, thus induced Beclin-1-dependent autophagy. Conclusion ABT-263 enhanced the macrophage function in aged mouse by increasing the Trem-2 receptors and inducing a beclin-1-dependent autophagy, consequently, protected the aged mouse from sepsis.

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ABT-263 enhanced bacterial phagocytosis of macrophages in aged mouse through Beclin-1-dependent autophagy

10.21203/rs.3.rs-19857/v2 ◽

2020 ◽

Author(s):

Yu Zhang ◽

Li-hua Tang ◽

Jia Lu ◽

Li-ming Xu ◽

Bao-li Cheng ◽

...

Keyword(s):

Survival Rate ◽

Cell Function ◽

The Elderly ◽

Peritoneal Macrophages ◽

Beclin 1 ◽

Aged Mouse ◽

Phagocytic Ability ◽

Age Related ◽

Slurry Injection

Abstract Background: Sepsis is a critical challenge for the elderly population as the immune function is less responsive by aging. Although cell numbers seem preserved in the elderly, macrophages present age-related function decline, which including reduced chemokines, phagocytosis, and autophagy. ABT-263, an inhibitor of the anti-apoptotic protein Bcl-2, is reported had a senolytic effect which can selectively clear the senescent cells in vivo and rejuvenate the aged tissues.Methods: We treated the aged (12-16 months) and young (4-6 months) C57BL/6 mouse with ABT-263, then gave the animals cecal slurry injection to induce sepsis to observe the effect of senolytic compound ABT-263 on the survival rate of sepsis. Additionally, we isolated peritoneal macrophages from the aged mouse to investigate the cell function and molecular mechanism. 3-methyladenine (3-MA), a phosphatidylinositol 3-kinases (PI3K) inhibitor, and rapamycin, an autophagy-enhancer, were used to block or mimic the autophagy, respectively. RT-PCR and Western Blot were used to detect autophagy related gene and protein changes in sepsis. EGFP-expressing E. Coli was used as a marker to evaluate the phagocytic ability of macrophages. Results: The results showed ABT-263 treatment improved the survival rate of sepsis in the aged mouse which related to autophagy, while blocking the autophagy can eliminate this effect. It is revealed that ABT-263 enhanced the phagocytic ability of the peritoneal macrophages by increasing the Trem-2 receptor. Additionally, ABT-263 blocked the binding of Bcl-2 to Beclin-1, thus induced Beclin-1-dependent autophagy. Conclusion: ABT-263 enhanced the macrophage function in aged mouse by increasing the Trem-2 receptors and inducing a beclin-1-dependent autophagy, consequently, protected the aged mouse from sepsis.

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Senolytic compound ABT-263 improved senescent macrophages function by inducing autophagy and protected the aged mouse from sepsis

10.21203/rs.3.rs-19857/v1 ◽

2020 ◽

Author(s):

Yu Zhang ◽

Li-hua Tang ◽

Jia Lu ◽

Li-ming Xu ◽

Bao-li Cheng ◽

...

Keyword(s):

Survival Rate ◽

Cell Function ◽

The Elderly ◽

Peritoneal Macrophages ◽

Aged Mouse ◽

Phagocytic Ability ◽

Age Related ◽

Apoptotic Protein ◽

Slurry Injection

Abstract Sepsis is a critical challenge for the elderly population as the immune function is less responsive by aging. Although cell numbers seem preserved in the elderly, macrophages present age-related function decline, which including reduced chemokines, phagocytosis, and autophagy. ABT-263, an inhibitor of the anti-apoptotic protein Bcl2, is reported had a senolytic effect which can selectively clear the senescent cells in vivo and rejuvenate the aged tissues. Therefore, we treated the aged mouse with ABT-263 and used cecal slurry injection to induce sepsis to observe its effect on the survival rate of sepsis. Besides, we isolated peritoneal macrophages from the aged mouse to investigate the cell function and molecular mechanism. 3-methyladenine (3-MA), a phosphatidylinositol 3-kinases (PI3K) inhibitor, and rapamycin, an autophagy-enhancer, were used to block or mimic the autophagy, respectively. EGFP-expressing E. Coli was used as a marker to evaluate the phagocytic ability of macrophages. The results showed ABT-263 treatment improved the survival rate of sepsis in the aged mouse which related to autophagy. Additionally, It is revealed that ABT-263 induced autophagy and enhanced the phagocytic ability of the peritoneal macrophages. However, blocking the autophagy can eliminate this effect. In conclusion, ABT-263 enhanced the macrophage function by inducing autophagy, consequently, protected the aged mouse from sepsis.

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Aging and dietary modulation of elastase and interleukin-1 beta secretion

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1995.268.1.r208 ◽

1995 ◽

Vol 268 (1) ◽

pp. R208-R213 ◽

Cited By ~ 3

Author(s):

J. G. Cannon ◽

M. A. Fiatarone ◽

M. Meydani ◽

J. Gong ◽

L. Scott ◽

...

Keyword(s):

Arachidonic Acid ◽

Cell Function ◽

Interleukin 1 ◽

Lipid Peroxide ◽

Arachidonic Acid Metabolism ◽

Interleukin 1 Beta ◽

Tension Development ◽

Age Related

Aging is associated with diminished immune function that may stem from alterations in arachidonic acid metabolism and lipid peroxidation. This study sought to determine if dietary modification of fatty acids influenced neutrophil and monocyte secretion after an in vivo inflammatory stress in older human subjects. Volunteers participated in protocols that forced their quadriceps muscles to lengthen during tension development (eccentric stress). These protocols can cause inflammatory foci in the muscle as well as alterations in circulating leukocyte function. In this study, in vivo neutrophil degranulation was assessed by plasma elastase concentrations, and mononuclear cell function was assessed by interleukin-1 beta (IL-1 beta) secretion in vitro. In response to eccentric stress, older subjects (> 60 yr old) taking a placebo had no apparent elastase response, whereas those taking fish oil supplements responded with a 142% increase in plasma elastase (P = 0.011), similar to responses of younger reference subjects (< 33 yr old) taking no supplement. Overall, elastase responses correlated with individual plasma arachidonic acid-to-eicosapentaenoic acid ratios (r = -0.881, P = 0.004). Thus apparent age-related differences in elastase release were reconciled by individual differences in fatty acid nutriture. No significant temporal changes in urinary lipid peroxide excretion or IL-1 beta secretion were observed; however, age-associated differences were found.

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Impact of endoplasmic reticulum stress on oocyte aging mechanisms

MHR Basic science of reproductive medicine ◽

10.1093/molehr/gaaa040 ◽

2020 ◽

Vol 26 (8) ◽

pp. 567-575

Author(s):

Isao Takehara ◽

Hideki Igarashi ◽

Jun Kawagoe ◽

Koki Matsuo ◽

Kyoko Takahashi ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Er Stress ◽

Embryo Development ◽

Oocyte Quality ◽

Initiation Factor ◽

Aged Mouse ◽

Age Related ◽

Initiation Factor 2 ◽

Aging Mechanisms

Abstract Endoplasmic reticulum (ER) stress is associated with several aging-related diseases; however, the mechanism underlying age-related deterioration of oocyte quality is unclear. Here, we used post-ovulatory, in vivo aged mouse oocytes as a model. Super-ovulated oocytes harvested from the oviduct at 14 h and 20 h post-hCG injection were designated as ‘fresh’ and ‘aged’, respectively. Embryo development following IVF was compared between fresh, aged and ER stress-induced oocytes. Expression of the ER stress marker GRP78 was examined at each stage. To evaluate the effect of salubrinal, an ER stress suppressor, on embryo development following IVF, expression levels of GRP78 and phospho-eukaryotic initiation factor 2 alpha were compared between aged and salubrinal-treated aged oocytes. Embryo transfer of salubrinal-treated aged oocytes was performed to examine the safety of salubrinal. Similar to aged oocytes, ER stress-induced oocytes showed lower fertilization rates and poor embryo development. Following IVF, expression of GRP78 decreased with embryo development. GRP78 expression was significantly higher in aged oocytes than in fresh oocytes. Salubrinal lowered GRP78 levels and improved embryo development. No adverse effect of salubrinal treatment was found on the birth weight of pups or on organogenesis in mice. The limitation of this study was that protein kinase-like ER kinase was the only ER stress pathway examined; the role of IRE1 and ATF6 pathways was not considered. Nevertheless, salubrinal can significantly improve embryo development in in vivo aged oocytes undergoing ER stress. Hence, regulation of ER stress might represent a promising therapeutic strategy to overcome poor oocyte quality.

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IL-6 increases B-cell IgG production in a feed-forward proinflammatory mechanism to skew hematopoiesis and elevate myeloid production

Blood ◽

10.1182/blood-2009-07-230631 ◽

2010 ◽

Vol 115 (23) ◽

pp. 4699-4706 ◽

Cited By ~ 49

Author(s):

Kenichiro Maeda ◽

Harshini Mehta ◽

Douglas A. Drevets ◽

K. Mark Coggeshall

Keyword(s):

B Cell ◽

Peritoneal Macrophages ◽

Direct Result ◽

Feed Forward ◽

Splenic Macrophages ◽

Age Related ◽

Show Evidence ◽

Igg Receptors ◽

Src Homology 2 Domain

Abstract Src homology 2 domain-containing inositol 5-phosphatase (SHIP−/−) animals display an age-related increase in interleukin-6 (IL-6), a decrease in B lymphopoiesis, and an elevation in myelopoiesis. We investigated the origin of the IL-6 production and show that it is largely produced by peritoneal and splenic macrophages. IL-6 production by these macrophages is not a direct result of the loss of SHIP: IL-6 production is not spontaneous, is absent from bone marrow-derived macrophages, declines with prolonged culture of macrophages, and requires a stimulus present in vivo. The IL-6–rich peritoneal cavity of SHIP−/− mice shows more than 700-fold more immunoglobulin G (IgG) than wild-type, approximately 20% of which is aggregated or in an immune complex and contains B220+ cells that secrete IgG. The SHIP-deficient peritoneal macrophages show evidence of IgG receptor stimulation. Animals lacking both the signal-transducing γ-chain of IgG receptors and SHIP or Ig and SHIP produce less IL-6. The data indicate a feed-forward process in which peripheral macrophages, responding through IgG receptors to secreted IgG, produce IL-6, to support further B-cell production of IgG. Because of the proinflammatory phenotype of SHIP−/− animals, these findings emphasize the importance of IL-6–neutralizing strategies in autoimmune and proinflammatory diseases.

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In Vivo Brain Glutathione is Higher in Older Age and Correlates with Mobility

10.1101/2020.10.14.339507 ◽

2020 ◽

Author(s):

K. E. Hupfeld ◽

H. W. Hyatt ◽

P. Alvarez Jerez ◽

M. Mikkelsen ◽

C. J. Hass ◽

...

Keyword(s):

Oxidative Stress ◽

Older Adults ◽

Motor Performance ◽

Resonance Spectroscopy ◽

Younger Adults ◽

Age Related ◽

Brain Oxidative Stress ◽

Brain Antioxidants ◽

Insight Into

AbstractBrain markers of oxidative damage increase with advancing age. In response, brain antioxidant levels may also increase with age, although this has not been well investigated. Here we used edited magnetic resonance spectroscopy to quantify endogenous levels of glutathione (GSH, one of the most abundant brain antioxidants) in 37 young (mean: 21.8 (2.5) years; 19 F) and 23 older adults (mean: 72.8 (8.9) years; 19 F). Accounting for age-related atrophy, we identified higher frontal and sensorimotor GSH levels for the older compared to the younger adults. For the older adults only, higher sensorimotor (but not frontal) GSH was correlated with poorer balance, gait, and manual dexterity. This suggests a regionally-specific relationship between higher brain oxidative stress levels and motor performance declines with age. We suggest these findings reflect a compensatory upregulation of GSH in response to increasing brain oxidative stress with normal aging. Together, these results provide insight into age differences in brain antioxidant levels and implications for motor function.

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Integrated In Vivo Quantitative Proteomics and Nutrient Tracing Reveals Age-Related Metabolic Rewiring of Pancreatic β Cell Function

Cell Reports ◽

10.1016/j.celrep.2018.11.031 ◽

2018 ◽

Vol 25 (10) ◽

pp. 2904-2918.e8 ◽

Cited By ~ 11

Author(s):

Matthew Wortham ◽

Jacqueline R. Benthuysen ◽

Martina Wallace ◽

Jeffrey N. Savas ◽

Francesca Mulas ◽

...

Keyword(s):

Quantitative Proteomics ◽

Cell Function ◽

Pancreatic Β Cell ◽

Β Cell ◽

Age Related ◽

Β Cell Function

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Senescent Cell-Secreted Netrin-1 Modulates Aging-Related Disorders by Recruiting Sympathetic Fibers

Frontiers in Aging Neuroscience ◽

10.3389/fnagi.2020.507140 ◽

2020 ◽

Vol 12 ◽

Author(s):

Ai Qing Yu ◽

Jie Wang ◽

Xiao Jia Zhou ◽

Ke Yu Chen ◽

You De Cao ◽

...

Keyword(s):

Cellular Senescence ◽

Molecular Mechanisms ◽

Human Colon ◽

Senescent Cell ◽

Aged Mouse ◽

Age Related ◽

Mouse Tissues ◽

6 Hydroxydopamine

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.

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Caffeine Inhibits Choroidal Neovascularization Through Mitigation of Inflammatory and Angiogenesis Activities

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.737426 ◽

2021 ◽

Vol 9 ◽

Author(s):

Christine M. Sorenson ◽

Yong-Seok Song ◽

Ismail S. Zaitoun ◽

Shoujian Wang ◽

Barbara A. Hanna ◽

...

Keyword(s):

Neurodegenerative Diseases ◽

Choroidal Neovascularization ◽

Cell Function ◽

Ex Vivo ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Retinal Pigment Epithelial Cells ◽

Endothelial Cell Migration ◽

Age Related

Adenosine receptors (AR) are widely expressed in a variety of tissues including the retina and brain. They are involved in adenosine-mediated immune responses underlying the onset and progression of neurodegenerative diseases. The expression of AR has been previously demonstrated in some retinal cells including endothelial cells and retinal pigment epithelial cells, but their expression in the choroid and choroidal cells remains unknown. Caffeine is a widely consumed AR antagonist that can influence inflammation and vascular cell function. It has established roles in the treatment of neonatal sleep apnea, acute migraine, and post lumbar puncture headache as well as the neurodegenerative diseases such as Parkinson and Alzheimer. More recently, AR antagonism with caffeine has been shown to protect preterm infants from ischemic retinopathy and retinal neovascularization. However, whether caffeine impacts the development and progression of ocular age-related diseases including neovascular age-related macular degermation remains unknown. Here, we examined the expression of AR in retinal and choroidal tissues and cells. We showed that antagonism of AR with caffeine or istradefylline decreased sprouting of thoracic aorta and choroid/retinal pigment epithelium explants in ex vivo cultures, consistent with caffeine’s ability to inhibit endothelial cell migration in culture. In vivo studies also demonstrated the efficacy of caffeine in inhibition of choroidal neovascularization and mononuclear phagocyte recruitment to the laser lesion sites. Istradefylline, a specific AR 2A antagonist, also decreased choroidal neovascularization. Collectively, our studies demonstrate an important role for expression of AR in the choroid whose antagonism mitigate choroidal inflammatory and angiogenesis activities.

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Integrated in vivo quantitative proteomics and nutrient tracing reveals age-related metabolic rewiring of pancreatic β-cell function

10.1101/451542 ◽

2018 ◽

Author(s):

Matthew Wortham ◽

Jacqueline R. Benthuysen ◽

Martina Wallace ◽

Jeffrey N. Savas ◽

Francesca Mulas ◽

...

Keyword(s):

Cell Function ◽

Coupling Factor ◽

Pancreatic Β Cell ◽

Β Cell ◽

Age Related ◽

Β Cell Function ◽

One Year ◽

Old Mice ◽

Age Related Changes

SummaryPancreatic β-cell physiology changes substantially throughout life; yet, the mechanisms that drive these changes are poorly understood. Here, we performed comprehensive in vivo quantitative proteomic profiling of pancreatic islets from adolescent and one-year-old mice. The analysis revealed striking differences in abundance of enzymes controlling glucose metabolism. We show that these changes in protein abundance are associated with higher activities of glucose metabolic enzymes involved in coupling factor generation as well as increased activity of the coupling factor-dependent amplifying pathway of insulin secretion. Nutrient tracing and targeted metabolomics demonstrated accelerated accumulation of glucose-derived metabolites and coupling factors in islets from one-year-old mice, indicating that age-related changes in glucose metabolism contribute to improved glucose-stimulated insulin secretion with age. Together, our study provides the first in-depth characterization of age-related changes in the islet proteome and establishes metabolic rewiring as an important mechanism for age-associated changes in β-cell function.

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