1
|
Kwon PK, Kim SW, De R, Jeong SW, Kim KT. Isoprocurcumenol Supports Keratinocyte Growth and Survival through Epidermal Growth Factor Receptor Activation. Int J Mol Sci 2021; 22:ijms222212579. [PMID: 34830467 PMCID: PMC8625800 DOI: 10.3390/ijms222212579] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/15/2021] [Accepted: 11/19/2021] [Indexed: 02/04/2023] Open
Abstract
Although proliferation of keratinocytes, a major type of skin cells, is a key factor in maintaining the function of skin, their ability to proliferate tends to diminish with age. To solve such a problem, researchers in medical and skin cosmetic fields have tried to utilize epidermal growth factor (EGF), but achieved limited success. Therefore, a small natural compound that can mimic the activity of EGF is highly desired in both medical and cosmetic fields. Here, using the modified biosensor system, we observed that natural small-compound isoprocurcumenol, which is a terpenoid molecule derived from turmeric, can activate EGFR signaling. It increased the phosphorylation of ERK and AKT, and upregulated the expression of genes related to cell growth and proliferation, such as c-myc, c-jun, c-fos, and egr-1. In addition, isoprocurcumenol induced the proliferation of keratinocytes in both physical and UVB-induced cellular damage, indicative of its function in skin regeneration. These findings reveal that EGF-like isoprocurcumenol promotes the proliferation of keratinocytes and further suggest its potential as an ingredient for medical and cosmetics use.
Collapse
Affiliation(s)
- Paul Kwangho Kwon
- Research Institute of Industrial Science and Technology, Pohang 37673, Gyeongbuk, Korea; (P.K.K.); (S.W.J.)
| | - Sung Wook Kim
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Gyeongbuk, Korea; (S.W.K.); (R.D.)
| | - Ranjit De
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Gyeongbuk, Korea; (S.W.K.); (R.D.)
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang 37673, Gyeongbuk, Korea
| | - Sung Woo Jeong
- Research Institute of Industrial Science and Technology, Pohang 37673, Gyeongbuk, Korea; (P.K.K.); (S.W.J.)
| | - Kyong-Tai Kim
- Research Institute of Industrial Science and Technology, Pohang 37673, Gyeongbuk, Korea; (P.K.K.); (S.W.J.)
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Gyeongbuk, Korea; (S.W.K.); (R.D.)
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang 37673, Gyeongbuk, Korea
- Correspondence:
| |
Collapse
|
2
|
Yasuda S, Nomi T, Hokuto D, Yoshikawa T, Matsuo Y, Sho M. Liver Regeneration After Major Liver Resection for Hepatocellular Carcinoma in the Elderly. J INVEST SURG 2018; 33:332-338. [PMID: 30388925 DOI: 10.1080/08941939.2018.1517839] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Background: With an aging population, more elderly patients are being considered for hepatic resection for hepatocellular carcinoma (HCC). This study aimed to evaluate postoperative outcomes including liver regeneration after major hepatectomy for HCC in the elderly.Methods: We assessed 41 patients who underwent major hepatectomy (≥3 segments) at our institute between 2000 and 2013. Patients were divided into two age groups, elderly group (age ≥70 years, n = 23) and younger group (age <70 years, n = 18). Clinicopathological data and outcomes were retrospectively compared. To evaluate the effect of aging on liver regeneration, we measured liver volumes preoperatively and at 1 and 6 months after liver resection using a 3D simulation imaging system.Results: Overall and major complications after hepatectomy were not different between elderly and younger groups, and no case of mortality was recorded. Moreover, recurrence-free and overall survivals were similar in both groups. With regard to liver regeneration, no differences were observed between elderly and younger groups at 1 and 6 months after liver resection. Baseline liver functions were comparable between the groups. Furthermore, the only factor associated with liver regeneration was resected liver volume (R2 = 0.631, p < 0.001). Age was not correlated with liver regeneration rate (R2 = 0.00537, p = 0.695).Conclusions: Liver regeneration after major hepatectomy for HCC was not affected by age and that resected liver volume is an important factor for liver regeneration. Short- and long-term outcomes after major hepatectomy were similar in elderly and younger patients.
Collapse
Affiliation(s)
- Satoshi Yasuda
- Department of Surgery, Nara Medical University, 840 Shijo-cho Kashihara-shi, Nara 634-8522, Japan
| | - Takeo Nomi
- Department of Surgery, Nara Medical University, 840 Shijo-cho Kashihara-shi, Nara 634-8522, Japan
| | - Daisuke Hokuto
- Department of Surgery, Nara Medical University, 840 Shijo-cho Kashihara-shi, Nara 634-8522, Japan
| | - Takahiro Yoshikawa
- Department of Surgery, Nara Medical University, 840 Shijo-cho Kashihara-shi, Nara 634-8522, Japan
| | - Yasuko Matsuo
- Department of Surgery, Nara Medical University, 840 Shijo-cho Kashihara-shi, Nara 634-8522, Japan
| | - Masayuki Sho
- Department of Surgery, Nara Medical University, 840 Shijo-cho Kashihara-shi, Nara 634-8522, Japan
| |
Collapse
|
3
|
Abstract
Aging is marked by changes that affect organs and resident stem cell function. Shorting of telomeres, DNA damage, oxidative stress, deregulation of genes and proteins, impaired cell-cell communication, and an altered systemic environment cause the eventual demise of cells. At the same time, reparative activities also decline. It is intriguing to correlate aging with the decline of regenerative abilities. Animal models with strong regenerative capabilities imply that aging processes might not be affecting regeneration. In this review, we selectively present age-dependent changes in stem/progenitor cells that are vital for tissue homeostasis and repair. In addition, the aging effect on regeneration following injury in organs such as lung, skeletal muscle, heart, nervous system, cochlear hair, lens, and liver are discussed. These tissues are also known for diseases such as heart attack, stroke, cognitive impairment, cataract, and hearing loss that occur mostly during aging in humans. Conclusively, vertebrate regeneration declines with age with the loss of stem/progenitor cell function. Future studies on improving the function of stem cells, along with studies in fish and amphibians where regeneration does not decline with age, will undoubtedly provide insights into both processes.
Collapse
Affiliation(s)
- Konstantinos Sousounis
- Department of Biology and Center for Tissue Regeneration and Engineering, University of Dayton, Dayton, Ohio, USA
| | - Joelle A Baddour
- Department of Chemical and Materials Engineering and Center for Tissue Regeneration and Engineering, University of Dayton, Dayton, Ohio, USA
| | - Panagiotis A Tsonis
- Department of Biology and Center for Tissue Regeneration and Engineering, University of Dayton, Dayton, Ohio, USA.
| |
Collapse
|
4
|
Low-power laser irradiation fails to improve liver regeneration in elderly rats at 48 h after 70 % resection. Lasers Med Sci 2014; 30:2003-8. [PMID: 24880927 DOI: 10.1007/s10103-014-1598-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 05/20/2014] [Indexed: 01/17/2023]
Abstract
The liver regeneration is an important clinical issue after major hepatectomies. Unfortunately, many organs (including the liver) exhibit age-related impairments regarding their regenerative capacity. Recent studies found that low-power laser irradiation (LPLI) has a stimulatory effect on the liver regeneration process. However, its effects in elderly remain unknown. Thus, this study aimed to investigate the main molecular mechanisms involved in liver regeneration of partially hepatectomized elderly rats exposed to LPLI. The effects of 15 min of LPLI (wavelength of 632.8 nm; fluence of 0.97 J/cm(2); total energy delivered of 3.6 J) were evaluated in hepatectomized elderly Wistar male rats. Afterwards, through immunoblotting approaches, the protein expression and phosphorylation levels of hepatocyte growth factor (HGF), Met, Akt and Erk 1/2 signaling pathways as well as the proliferating cell nuclear antigen (PCNA) were investigated. It was observed that LPLI was not able to improve liver regeneration in elderly rats as evidenced by the lack of improvement of HGF and PCNA protein expression or phosphorylation levels of Met, Akt and Erk 1/2 in the remnant livers. In sum, this study demonstrated that the main molecular pathway, i.e. HGF/Met → Akt and Erk 1/2 → PCNA, involved in the hepatic regeneration process was not improved by LPLI in elderly hepatectomized rats, which in turn rules out LPLI as an adjuvant therapy, as observed in this protocol of liver regeneration evaluation (i.e. at 48 h after 70 % resection), in elderly.
Collapse
|
5
|
Gonzalez Pardo V, Russo de Boland A. Age-related changes in the response of intestinal cells to 1α,25(OH)2-vitamin D3. Ageing Res Rev 2013; 12:76-89. [PMID: 22706185 DOI: 10.1016/j.arr.2012.06.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 06/01/2012] [Accepted: 06/06/2012] [Indexed: 12/14/2022]
Abstract
The hormonally active form of vitamin D(3), 1α,25(OH)(2)-vitamin D(3), acts in intestine, its major target tissue, where its actions are of regulatory and developmental importance: regulation of intracellular calcium through modulation of second messengers and activation of mitogenic cascades leading to cell proliferation. Several causes have been postulated to modify the hormone response in intestinal cells with ageing, among them, alterations of vitamin D receptor (VDR) levels and binding sites, reduced expression of G-proteins and hormone signal transduction changes. The current review summarizes the actual knowledge regarding the molecular and biochemical basis of age-impaired 1α,25(OH)(2)-vitamin D(3) receptor-mediated signaling in intestinal cells. A fundamental understanding why the hormone functions are impaired with age will enhance our knowledge of its importance in intestinal cell physiology.
Collapse
Affiliation(s)
- Verónica Gonzalez Pardo
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Consejo Nacional de Investigaciones Científicas y Técnicas, Bahía Blanca, Argentina
| | | |
Collapse
|
6
|
Sone K, Mori M, Mori N. Selective upregulation of p66-Shc gene expression in the liver and brain of aged rats. Arch Gerontol Geriatr 2012; 55:744-8. [DOI: 10.1016/j.archger.2011.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 11/02/2011] [Accepted: 11/04/2011] [Indexed: 01/23/2023]
|
7
|
Kobayashi T, Saito Y, Ohtake Y, Maruko A, Yamamoto Y, Yamamoto F, Kuwahara Y, Fukumoto M, Fukumoto M, Ohkubo Y. Effect of aging on norepinephrine-related proliferative response in primary cultured periportal and perivenous hepatocytes. Am J Physiol Gastrointest Liver Physiol 2012; 303:G861-9. [PMID: 22837346 DOI: 10.1152/ajpgi.00081.2012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Norepinephrine (NE) amplifies the mitogenic effect of EGF in a rat liver through the adrenergic receptor coupled with G protein, Ghα. Ghα is also known as a transglutaminase 2 (TG2), whose cross-linking activity is implicated in hepatocyte growth. Recently, we found that NE-induced amplification of EGF-induced DNA synthesis in hepatocytes obtained from perivenous regions of liver is caused by inhibiting the downregulation of EGF receptor (EGFR) by TG2. In the present study, we investigated the effect of aging on NE-related proliferative response. Hepatocytes were obtained from the liver of 7- and 90-wk-old rats. To examine this in detail, periportal hepatocytes (PPH) and perivenous hepatocytes (PVH) were isolated using the digitonin/collagenase perfusion technique. EGF or NE receptor binding was analyzed by Scatchard analysis. Changes in NE-induced DNA synthesis, G protein activity, and TG2 activity were measured. NE slightly potentiated [125I]EGF binding to EGFR, and EGF-induced DNA synthesis in PVH but not in PPH. [3H]NE binding studies indicated that PVH have a greater number of receptors than PPH, and that the number of receptors in both subpopulations increased with aging. NE-induced changes in G protein activity and TG2 activity in 90-wk-old rats were slight compared with 7-wk-old rats. These results suggest that NE results in a slight recovery effect on the age-related decline in EGF-induced DNA synthesis because of incomplete switching of the function from TG2 to Ghα.
Collapse
Affiliation(s)
- Tomonori Kobayashi
- Department of Radiopharmacy, Tohoku Pharmaceutical University, 4-4-1, Komatsushima, Aoba-ku, Sendai, Miyagi 981-8558, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Liver regeneration and aging: a current perspective. Curr Gerontol Geriatr Res 2011; 2011:526379. [PMID: 21912543 PMCID: PMC3170699 DOI: 10.1155/2011/526379] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Accepted: 07/06/2011] [Indexed: 12/22/2022] Open
Abstract
Many organ systems exhibit significant age-related deficits, but,
based on studies in old rodents and elderly humans, the liver
appears to be relatively protected from such changes. A
remarkable feature of the liver is its capacity to regenerate its
mass following partial hepatectomy. Reports suggests that aging
compromises the liver's regenerative capacity, both in the
rate and to the extent the organ's original volume is
restored. There has been modest definitive information as to which
cellular and molecular mechanisms regulating hepatic regeneration
are affected by aging. Changes in hepatic sensitivity to growth
factors, for example, epidermal growth factor (EGF), appear to influence
regeneration in old animals. Studies have demonstrated (a) a 60%
decline in EGF binding to hepatocyte plasma membranes, (b) reduced
expression of the hepatic high affinity EGF receptor and (c) a
block between G1 and S-phases of the cell cycle in old rats
following EGF stimulation. Recent studies suggest that reduced
phosphorylation and dimerization of the EGF receptor, critical
steps in the activation of the extracellular signal-regulated
kinase pathway and subsequent cell proliferation are responsible.
Other studies have demonstrated that aging affects the
upregulation of a Forkhead Box transcription factor, FoxM1B, which
is essential for growth hormone-stimulated liver regeneration in
hepatectomized mice. Aging appears to compromise liver
regeneration by influencing several pathways, the result of which
is a reduction in the rate of regeneration, but not in the
capacity to restore the organ to its original volume.
Collapse
|
9
|
Kamat A, Ghosh PM, Glover RL, Zhu B, Yeh CK, Choudhury GG, Katz MS. Reduced expression of epidermal growth factor receptors in rat liver during aging. J Gerontol A Biol Sci Med Sci 2008; 63:683-92. [PMID: 18693222 DOI: 10.1093/gerona/63.7.683] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Proliferative responsiveness of hepatocytes to epidermal growth factor (EGF) declines during aging. The role of EGF receptors in mediating age-dependent changes of EGF-induced mitogenic signaling in liver remains incompletely understood. We assessed EGF receptor expression levels in whole liver specimens as well as in freshly isolated and cultured hepatocytes from young adult and senescent Fischer 344 male rats. Hepatic EGF receptor messenger RNA and protein levels, and the number of high- and low-affinity receptor binding sites, decreased with aging. Ligand-induced EGF receptor activation, determined by receptor dimerization and tyrosine phosphorylation, was reduced in old animals in parallel with the age-related decline in receptor expression. Stimulation of the extracellular signal-regulated kinase pathway by EGF was also attenuated in hepatocytes from old animals. Our results implicate decreased expression of EGF receptors as a key determinant of reduced mitogenic signaling responsive to EGF stimulation of liver during aging.
Collapse
Affiliation(s)
- Amrita Kamat
- Geriatric Research Education and Clinical Center (182), Audie L Murphy Division, South Texas Veterans Health Care System, San Antonio, TX 78229, USA.
| | | | | | | | | | | | | |
Collapse
|
10
|
Ohtake Y, Maruko A, Ohishi N, Fukumoto M, Ohkubo Y. Effect of aging on EGF-induced proliferative response in primary cultured periportal and perivenous hepatocytes. J Hepatol 2008; 48:246-54. [PMID: 18006107 DOI: 10.1016/j.jhep.2007.08.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2007] [Revised: 07/17/2007] [Accepted: 08/20/2007] [Indexed: 12/26/2022]
Abstract
BACKGROUND/AIMS Aging relates to declined proliferative capacity of the liver, but the molecular mechanism is not well understood. We examined whether functional changes of epidermal growth factor (EGF) receptor (EGFR) are involved in age-related decline in EGF-induced DNA synthesis using hepatocytes isolated in periportal and perivenous regions of the liver, which differ in the proliferative capacity. METHODS Periportal hepatocytes (PPH) and perivenous hepatocytes (PVH) in 7-, 30-, and 90-week-old rats were isolated using the digitonin/collagenase perfusion technique. DNA synthesis was assessed by [methyl-(3)H]thymidine incorporation. EGFR binding affinity to EGF was analyzed by Scatchard analysis using [(125)I]EGF. EGFR dimerization and phosphorylation were determined by Western blot analysis. RESULTS EGF-induced DNA synthesis was greater in PPH than in PVH from rats of 7 weeks, but the zonal difference disappeared with aging. [(125)I]EGF binding studies indicated that high-affinity EGFR in both subpopulations also disappeared with aging. Furthermore, EGF-induced dimerization in both subpopulations was down-regulated with aging, and the pattern of EGFR phosphorylation was parallel to that of dimerization. CONCLUSIONS These data suggest that age-related decline in EGF-induced DNA synthesis of PPH and PVH is caused by down-regulation of EGFR dimerization through the decrease of high-affinity EGFR.
Collapse
Affiliation(s)
- Yosuke Ohtake
- Department of Radiopharmacy, Tohoku Pharmaceutical University, 4-4-1, Komatsushima, Aoba-ku, Sendai, Miyagi 981-8558, Japan.
| | | | | | | | | |
Collapse
|
11
|
Avissar NE, Toia L, Sax HC. Epidermal growth factor and/or growth hormone induce differential, side-specific signal transduction protein phosphorylation in enterocytes. JPEN J Parenter Enteral Nutr 2006; 29:322-35; discussion 335-6. [PMID: 16107595 DOI: 10.1177/0148607105029005322] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Epidermal growth factor (EGF) plus growth hormone (GH) enhances luminal glutamine transport into rabbit and human intestinal cells. Our objective was to screen for activation status of signal proteins in C2(BBe)1 cells (enterocyte-like cell line) in response to side-specific EGF or GH treatment and to investigate the dependence of EGF receptor (EGFR) phosphorylation status on its tyrosine kinase. METHODS C2(BBe)1 cells on Transwells were treated for 15 minutes on either the basolateral or apical-side with EGF or GH. Lysates underwent Kinetworks phospho site-screen-2.1 analysis (duplicate experiments). In addition, lysates from cells treated as above with or without tyrphostin AG1478 (a specific EGFR tyrosine kinase inhibitor) underwent Western blot analysis for total EGFR and EGFR phosphorylated on tyrosine 1173, 1086 or 1068 (4-7 experiments). RESULTS Kinetworks phospho-screening demonstrated a broad range of interactions dependent on both side of exposure and protein studied. From this screen, it appears that ErbB2, Met, and insulin receptor (R)/insulin-like growth factor 1 R are not involved in the growth factors signals. For EGFR phosphorylation, basolateral, but not apical, EGF was a strong activator. Synergism was seen, but only with apical EGF plus basolateral GH. All EGFR phosphorylations were EGFR tyrosine kinase dependent. In contradistinction, apical EGF phosphorylated FAK and MAPKs. CONCLUSIONS Kinetworks phosphoprotein screens can suggest pathways involved in side-specific and synergistic interaction between EGF and GH. For EGFR, synergism by EGF + GH was noticed only with Ap EGF plus Bl GH and was EGFR tyrosine kinase dependent. Adaptive intestinal responses due to enterally administrated EGF might be accelerated by the availability of parenteral GH.
Collapse
Affiliation(s)
- Nelly E Avissar
- University of Rochester School of Medicine and Dentistry, Department of Surgery, Medical Center, 601 Elmwood Avenue, Rochester, NY 14642, USA.
| | | | | |
Collapse
|
12
|
Gurjala AN, Liu WR, Mogford JE, Procaccini PSA, Mustoe TA. Age-dependent response of primary human dermal fibroblasts to oxidative stress: cell survival, pro-survival kinases, and entrance into cellular senescence. Wound Repair Regen 2005; 13:565-75. [PMID: 16283872 DOI: 10.1111/j.1524-475x.2005.00079.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A central question in cell biology is how cells become senescent. After a finite number of cell divisions, normal cultured human cells enter a state of irreversible growth arrest, termed "replicative senescence." Alternatively, oxidative stress in the form of hydrogen peroxide (H(2)O(2)) can render human dermal fibroblasts (HDFs) nonproliferative and quiescent, a phenomenon known as stress-induced premature senescence (SIPS). Although critical to the understanding of the pathophysiological basis of many diseases, there is no research to date that has simultaneously examined the interactions between age, oxidative stress, and SIPS. Therefore, the goals of this study were to examine in concert the interactions between these three factors in primary HDFs, and to test our central hypothesis that aging lowers the ability of primary HDFs to respond to oxidative stress. Our data provide, for the first time, evidence that aging dramatically reduces the capacity of primary HDFs to respond to the challenge of hydrogen peroxide. Specifically, aged HDFs showed decreased cell viability, decreased phosphorylation (activation) of pro-survival kinases (Akt and ERK 1/2), and increased entrance into a senescent state when compared with their younger counterparts. Another important conclusion of this study is that blockade of transforming growth factor-beta1 had a pronounced "rescue effect" in the aged, preventing entrance of HDFs into cellular senescence.
Collapse
Affiliation(s)
- Anandev N Gurjala
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | | | | | | | | |
Collapse
|
13
|
Shi B, Isseroff RR. Epidermal growth factor (EGF)-mediated DNA-binding activity of AP-1 is attenuated in senescent human epidermal keratinocytes. Exp Dermatol 2005; 14:519-27. [PMID: 15946240 DOI: 10.1111/j.0906-6705.2005.00317.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The proliferative responses of cells to mitogens decrease during aging, and this may result from age-related defects in signal transduction in response to mitogens. In this study, we have investigated the age-related alteration of responses to epidermal growth factor (EGF) in cultured human keratinocytes that were senesced in vitro by repeated passage. The stimulation with EGF increased the DNA-binding activity of activator protein 1 (AP-1), an important transcription factor for cell proliferation, in young keratinocytes, whereas the binding activity showed little or slight change in the senescent cells. The induced DNA-binding activity of AP-1 in young cells was inhibited by PD 98059, an inhibitor of MEK, and partially inhibited by GF 109203X, an inhibitor of protein kinase C. Western blot analysis demonstrated that EGF induced dramatic increase in the phosphorylation of EGF receptor (EGFR) and extracellular signal-regulated kinases (ERK) in young cells, while this phosphorylation was much less profound in senescent cells. Finally, the application of EGF to young cells resulted in increased phosphorylation of Fra-2, a Fos protein component of the Jun/Fos heterodimer AP-1 complex. This EGF-induced Fra-2 phosphorylation was attenuated in senescent cells. Taken together, our study suggests that the signal transduction mediated by EGF/ERK pathway is altered in senescent human keratinocytes, and this change may be attributed, in part, to the decreased AP-1 transcription activity observed in senescent keratinocytes.
Collapse
Affiliation(s)
- Biao Shi
- Department of Dermatology, University of California Davis School of Medicine, Davis, CA, USA
| | | |
Collapse
|
14
|
Cho KA, Park SC. Caveolin-1 as a prime modulator of aging: a new modality for phenotypic restoration? Mech Ageing Dev 2005; 126:105-10. [PMID: 15610768 DOI: 10.1016/j.mad.2004.09.029] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Aging can be characterized by structural changes and functional deterioration during the lifetime, for which hundreds of explanations have been put forward. Recently, we have proposed the gate theory of aging, in which gatekeeper molecules at the membrane level would play the prime role in determining the senescent phenotype. Caveolin-1 would be a prime candidate for such a role as a major determinant of the aging process. Caveolin-1 can associate with a variety of molecules, involved in signal transduction, endocytosis and transcytosis, cytoskeletal arrangement, etc. The level of caveolin-1 is strictly regulated to maintain cellular integrity, leading to cellular transformation if depleted, and to the senescent phenotype if overexpressed. In case of senescent cells, the functional and physiological responses to the mitogenic stimuli can be restored and the morphological shape can be resumed by simple adjustment of caveolin-1 status. Therefore, it is suggested that prime modulator molecules, represented by caveolin-1, play a key role in determining the senescent phenotype, either as a physiological response or altered morphology.
Collapse
Affiliation(s)
- Kyung A Cho
- Department of Biochemistry and Molecular Biology, Aging and Apoptosis Research Center, Seoul National University College of Medicine, 28 Yungon Dong, Chong No Ku, Seoul 110-799, South Korea
| | | |
Collapse
|
15
|
Rice KM, Kinnard RS, Harris R, Wright GL, Blough ER. Effects of aging on pressure-induced MAPK activation in the rat aorta. Pflugers Arch 2005; 450:192-9. [PMID: 15877234 DOI: 10.1007/s00424-005-1383-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2004] [Accepted: 01/13/2005] [Indexed: 11/30/2022]
Abstract
With increasing age, the cardiovascular system experiences substantial alterations in cellular morphology and function. Whilst the factors regulating these changes are unknown, the mitogen-activated protein kinase (MAPK) pathways have emerged as critical components for mediating numerous cellular responses including control of cell growth, differentiation and adaptation. Here we compare the expression, basal activation and the ability of increased pressure to activate the MAPK pathways in adult (6-month-old), aged (30-month-old) and very aged (36-month-old) Fischer 344xBrown Norway F1 hybrid rats. Histochemical analysis demonstrated an age-related increase in tunica media thickness of approximately 11 and 21% in aortae from aged and very aged animals, respectively. Western blot analysis of the MAPK family extracellular signal-regulated kinase (ERK 1/2), p38, and c-Jun NH2 -terminal kinase (JNK) MAPKs showed differential expression and activation among these proteins with age. Expression of ERK 1/2, p38, and JNK were unchanged, slightly increased (10+/-17.5%) or significantly increased (72.3+/-27%), respectively, in very aged aortae. In contrast, basal activation levels of these proteins were reduced (-26.2+/-7.4%), markedly increased (97.0+/-16.8%), and slightly increased (14.4+/-4.5%), respectively, in very aged compared with 6-month rat aortae. An acute increase of aortic intraluminal pressure (200 mmHg) indicated that ERK 1/2 regulation differed from p38 or JNK. Pressure loading-induced phosphorylation of ERK1/2 was unchanged or increased with aging while p38 and JNK phosphorylation was attenuated (P<0.01). These observations confirm previous conclusions that MAPK proteins are regulated mechanically and expand these studies to suggest that MAPK expression and the control of activation are changed with aging.
Collapse
Affiliation(s)
- K M Rice
- Department of Biological Sciences, Marshall University, Huntington, WV 2755, USA
| | | | | | | | | |
Collapse
|
16
|
Abstract
Hepatitis A virus (HAV) has been adapted to grow efficiently in primate and some nonprimate cell lines but not in cells of murine origin. To understand the inability of the virus to grow in mouse cells, we studied the replication of HAV in immortalized and nontransformed MMH-D3 mouse liver cells, which require growth factors and collagen to maintain their phenotype. HAV grew in MMH-D3 cells transfected with virion RNA but not in those infected with viral particles, indicating a cell entry block for HAV. However, MMH-D3 cells cultured under suboptimal conditions in the absence of growth factors acquired susceptibility to HAV infection. Serial passages of the virus in MMH-D3 cells under suboptimal growth conditions resulted in the selection of HAV variants that grew efficiently in MMH-D3 cells cultured under both optimal and suboptimal conditions. Nucleotide sequence analysis of the MMH-D3 cell-adapted HAV revealed that N1237D and D2132G substitutions were present in the capsid regions of six viral clones. These two mutations are most likely located on the surface of the virion and may play a role in the entry of HAV into the mouse liver cells. Our results demonstrate that mouse hepatocyte-like cells code for all factors required for the efficient growth of HAV in cell culture.
Collapse
Affiliation(s)
- Dino A Feigelstock
- Laboratory of Hepatitis, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20852, USA
| | | | | |
Collapse
|
17
|
Rescan C, Le Bras S, Lefebvre VH, Frandsen U, Klein T, Foschi M, Pipeleers DG, Scharfmann R, Madsen OD, Heimberg H. EGF-induced proliferation of adult human pancreatic duct cells is mediated by the MEK/ERK cascade. J Transl Med 2005; 85:65-74. [PMID: 15543206 DOI: 10.1038/labinvest.3700204] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Human postnatal pancreatic duct cells are a potential source of new beta cells. Factors regulating proliferation of human pancreatic duct cells in vitro are unknown. In several other cell types, this process is influenced by ligands of the ErbB receptor family. The expression and functionality of the ErbB family members and their possible role in duct cell proliferation were determined. In cultured adult human pancreatic duct cells the different members of the ErbB family (ErbB1-4) were present at transcript and protein level. Stimulation of the duct cells with epidermal growth factor (EGF) and betacellulin results in Tyr-phosphorylation of ErbB1 and ErbB2, followed by activation of Shc, MEK1/2 and ERK1/2. Duct cells with activated ErbB signaling changed morphology and motility. EGF induced proliferation of a fraction of the duct cells and treatment with PD98059 prevented Ki67 expression in EGF-supplemented cells. When transduced with recombinant adenovirus expressing constitutively activated MEK1, duct cells proliferate and spread even in the absence of EGF. Importantly, the adult human duct cells retain their capacity to recapitulate ngn3-induced embryonic (neuro)endocrine differentiation after proliferation. Therefore, the present data support a possible role for human adult pancreatic duct cells, following expansion and transdifferentiation, as a source of insulin by transplantation to type I diabetes patients.
Collapse
Affiliation(s)
- Claude Rescan
- The JDRF Center for Beta Cell Therapy in Europe, University of Florence, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Russo de Boland A. Age-related changes in the response of intestinal cells to parathyroid hormone. Mech Ageing Dev 2004; 125:877-88. [PMID: 15563934 DOI: 10.1016/j.mad.2004.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The concept of the role(s) of parathyroid hormone (PTH), has expanded from that on acting on the classical target tissues, bone and kidney, to the intestine where its actions are of regulatory and developmental importance: regulation of intracellular calcium through modulation of second messengers and, activation of mitogenic cascades leading to cell proliferation. Several causes have been postulated to modify the hormone response in intestinal cells with ageing, among them, alterations of PTH receptor (PTHR1) binding sites, reduced expression of G proteins and hormone signal transduction changes. The current review summarizes the actual knowledge regarding the molecular and biochemical basis of age-impaired PTH receptor-mediated signaling in intestinal cells. A fundamental understanding of why PTH functions are impaired with age will enhance our understanding of its importance in intestinal cell physiology.
Collapse
Affiliation(s)
- Ana Russo de Boland
- Dpto. Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, San Juan 670, 8000 Bahía Blanca, Argentina.
| |
Collapse
|
19
|
Miura Y. Oxidative stress, radiation-adaptive responses, and aging. JOURNAL OF RADIATION RESEARCH 2004; 45:357-372. [PMID: 15613781 DOI: 10.1269/jrr.45.357] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Organisms living in an aerobic environment were forced to evolve effective cellular strategies to detoxify reactive oxygen species. Besides diverse antioxidant enzymes and compounds, DNA repair enzymes, and disassembly systems, which remove damaged proteins, regulation systems that control transcription, translation, and activation have also been developed. The adaptive responses, especially those to radiation, are defensive regulation mechanisms by which oxidative stress (conditioning irradiation) elicits a response against damage because of subsequent stress (challenging irradiation). Although many researchers have investigated these molecular mechanisms, they remain obscure because of their complex signaling pathways and the involvement of various proteins. This article reviews the factors concerned with radiation-adaptive response, the signaling pathways activated by conditioning irradiation, and the effects of aging on radiation-adaptive response. The proteomics approach is also introduced, which is a useful method for studying stress response in cells.
Collapse
Affiliation(s)
- Yuri Miura
- Redox regulation research group, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku. Tokyo, Japan.
| |
Collapse
|
20
|
Pardo VG, de Boland AR. Tyrosine phosphorylation signalling dependent on 1α,25(OH)2-vitamin D3 in rat intestinal cells: effect of ageing. Int J Biochem Cell Biol 2004; 36:489-504. [PMID: 14687927 DOI: 10.1016/j.biocel.2003.08.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In intestinal cells, as in other target cells, 1alpha,25(OH)(2)D(3) elicits long-term and short-term responses which involve genomic and non-genomic mode of actions, respectively. There is evidence indicating that activation of tyrosine phosphorylation pathways may participate in the responses induced by 1alpha,25(OH)(2)D(3) through its non-genomic mechanism. In this study we have evaluated the involvement of 1alpha,25(OH)(2)D(3) in the tyrosine phosphorylation of PLCgamma and MAPK (ERK1/2) in enterocytes from young (3 months) and aged (24 months) rats. Immunochemical analysis revealed that the hormone stimulates PLCgamma tyrosine phosphorylation in young rat enterocytes. Hormone effect on PLCgamma is rapid, peaking at 2 min (+100%), is dose-dependent (10(-10) to 10(-8)M) and decreases with ageing. 1alpha,25(OH)(2)D(3) also induces the phosphorylation and activation of the mitogen-activated-protein kinases ERK1 and ERK2, effect which was evident at 1 min (three-fold) and reached a maximum at 2 min (six-fold). Hormone-dependent ERK1 and ERK2 phosphorylation and activity is greatly reduced in enterocytes from old rats. In both, young and aged animals, 1alpha,25(OH)(2)D(3)-induced PLCgamma and ERK1/2 phosphorylation was effectively suppressed by the tyrosine kinase inhibitor genistein (100 uM) and suppressed to a great extent by PP1, an inhibitor of c-Src kinases. LY294002, a specific inhibitor of PI3 kinase (PI3K), enzyme with an important role in mitogenesis, did not affect hormone-dependent ERK1/2 phosphorylation, indicating that PI3K is not involved in 1alpha,25(OH)(2)D(3)-induced MAPK activation. In agreement with this data, enzyme activity assays and tyrosine phosphorylation of the regulatory subunit (p85) of PI3K showed that the hormone has no effect on the enzyme activity in rat enterocytes. Taken together, the present study suggest that in intestinal cells, tyrosine phosphorylation is an important mechanism of 1alpha,25(OH)(2)D(3) involved in PLCgamma and MAPK regulation and that this mechanism is impair with ageing.
Collapse
Affiliation(s)
- Verónica González Pardo
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur., 8000 Bahía Blanca, Argentina
| | | |
Collapse
|
21
|
Tran KT, Rusu SD, Satish L, Wells A. Aging-related attenuation of EGF receptor signaling is mediated in part by increased protein tyrosine phosphatase activity. Exp Cell Res 2003; 289:359-67. [PMID: 14499637 DOI: 10.1016/s0014-4827(03)00287-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
As fibroblasts near senescence, their responsiveness to external signals diminishes. This well-documented phenomenon likely underlies physiological deterioration and limited tissue regeneration in aging individuals. Understanding the underlying molecular mechanisms would provide opportunities to ameliorate these situations. A key stimulus for human dermal fibroblasts are ligands for the epidermal growth factor receptor (EGFR). We have shown earlier that EGFR expression decreases by about half in near senescent fibroblasts (Shiraha et al., 2000, J. Biol. Chem. 275 (25), 19343-19351). However, as the cell responses are nearly absent near senescence, other aging-related signal attenuation changes must also occur. Herein, we show that EGFR signaling as determined by receptor autophosphorylation is diminished over 80%, with a corresponding decrease in the phosphorylation of the immediate postreceptor adaptor Shc. Interestingly, we found that this was due at least in part to increased dephosphorylation of EGFR. The global cell phosphotyrosine phosphatase activity increased some threefold in near senescent cells. An initial survey of EGFR-associated protein tyrosine phosphatases (PTPases) showed that SHP-1 (PTPIC, HCP, SHPTP-1) and PTPIB levels are increased in parallel in these cells. Concomitantly, we also discovered an increase in expression of receptor protein tyrosine phosphatase alpha (RPTPalpha). Last, inhibition of protein tyrosine phosphatases by sodium orthovanadate in near senescent cells resulted in increased EGFR phosphorylation. These data support a model in which, near senescence, dermal fibroblasts become resistant to EGFR-mediated stimuli by a combination of receptor downregulation and increased signal attenuation.
Collapse
Affiliation(s)
- Kien T Tran
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | | | | | | |
Collapse
|
22
|
Abstract
Aging is often characterized by reduced stress tolerance and decreased proliferative capacity, but little is known about the effects of aging on signaling pathways important in regulating these responses. Recent studies from our laboratory have implicated impairments in epidermal growth factor receptor (EGFR) signaling and extracellular signal-regulated kinase (ERK) activation to both effects in rat hepatocytes. Here we investigated the responsiveness of hepatocytes derived from young (4-5 months) and aged (24-29 months) mice to proliferative signals (low concentrations of H2O2 and epidermal growth factor [EGF] stimulation), and oxidant injury (high H2O2 concentrations). Old hepatocytes displayed lower levels of DNA synthesis in response to low H(2)O(2) concentrations (5-10 microM) and EGF stimulation, and reduced survival following treatment with high H2O2 concentrations (20-50 microM). Both effects were associated with reduced activation of ERK and diminished phosphorylation of EGFR tyrosine residue 1173. p38 was also activated by H2O2, but to a greater extent in old cells. Pharmacologic inhibition of ERK increased the sensitivity of young cells to H2O2-induced cell death, while inhibition of p38 decreased the sensitivity of old cells. Our findings suggest that impairments in common signaling events underlie age-related declines in proliferative capacity and oxidative stress tolerance in mouse hepatocytes, and that an imbalance in ERK and p38 activities contributes to the greater sensitivity of aged cells to H2O2.
Collapse
Affiliation(s)
- Ji Li
- Department of Internal Medicine, Section of Geriatrics, Yale University School of Medicine, New Haven, CT 06511, USA.
| | | |
Collapse
|
23
|
Nagano H, Noguchi T, Inagaki K, Yoon S, Matozaki T, Itoh H, Kasuga M, Hayashi Y. Downregulation of stomach cancer-associated protein tyrosine phosphatase-1 (SAP-1) in advanced human hepatocellular carcinoma. Oncogene 2003; 22:4656-63. [PMID: 12879010 DOI: 10.1038/sj.onc.1206588] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
SAP-1 (stomach cancer-associated protein tyrosine phosphatase-1) is a transmembrane-type protein tyrosine phosphatase that has been implicated as a negative regulator of integrin-mediated signaling. The potential role of this enzyme in hepatocarcinogenesis has now been investigated by examining its expression in 32 surgically excised human hepatocellular carcinoma (HCC) specimens. Both immunohistochemical and immunoblot analyses revealed that normal liver tissue, as well as tissue affected by chronic hepatitis or cirrhosis, contained substantial amounts of SAP-1. The expression level of SAP-1 in 75% of well-differentiated HCCs was similar to or higher than that observed in the surrounding noncancerous tissue. In contrast, the abundance of SAP-1 in 85.7% of moderately differentiated HCCs and in all poorly differentiated HCCs was greatly reduced compared with that in the adjacent tissue. Indeed, SAP-1 was almost undetectable in 83.3% of poorly differentiated HCCs. Furthermore, expression of recombinant SAP-1 in two highly motile human HCC cell lines resulted in a change in morphology and a marked reduction in both migratory activity and growth rate. In conclusion, these results indicate that SAP-1 expression is downregulated during the dedifferentiation of human HCC, and that this downregulation may play a causal role in disease progression.
Collapse
Affiliation(s)
- Hidenobu Nagano
- Division of Diabetes, Digestive and Kidney Diseases, Department of Clinical Molecular Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
| | | | | | | | | | | | | | | |
Collapse
|
24
|
Gennaro G, Ménard C, Giasson E, Michaud SE, Palasis M, Meloche S, Rivard A. Role of p44/p42 MAP kinase in the age-dependent increase in vascular smooth muscle cell proliferation and neointimal formation. Arterioscler Thromb Vasc Biol 2003; 23:204-10. [PMID: 12588760 DOI: 10.1161/01.atv.0000053182.58636.be] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
OBJECTIVE Age-dependent increase in vascular smooth muscle cell (VSMC) proliferation is thought to contribute to the pathology of atherosclerotic diseases. In this study, we investigated the role of mitogen-activated protein kinases (MAPKs) on VSMC proliferation and neointimal formation in the context of aging. METHODS AND RESULTS VSMCs were isolated from the aorta of young and old rabbits. The proliferative index after serum stimulation was significantly increased in old versus young VSMCs. This was associated with a significant and specific age-dependent increase in p44/p42 MAPK activation. Treatment with MEK inhibitor PD98059 successfully inhibited p44/p42 MAPK activities and VSMC proliferation. These results were confirmed in vivo using a model of balloon injury in rabbit iliac arteries. p44/p42 MAPK activities were rapidly induced by angioplasty in young and old animals. However, the levels of p44/p42 MAPK activities achieved in arteries of old rabbits were significantly higher than those of young rabbits. This was associated with a higher cellular proliferative index and a significant increase in neointimal formation in old animals. Local delivery of PD98059 in old rabbits successfully inhibited p44/p42 MAPK activities after angioplasty, which led to a significant reduction in cellular proliferation and neointimal formation in treated animals. CONCLUSIONS Our study suggests for the first time that increased p44/p42 MAPK activation contributes to augmented VSMC proliferation and neointimal formation with aging. p44/p42 MAPK inhibition could represent a novel therapeutic avenue against atherosclerotic diseases.
Collapse
MESH Headings
- Age Factors
- Aging/drug effects
- Aging/physiology
- Animals
- Aorta/drug effects
- Aorta/enzymology
- Aorta/pathology
- Apoptosis/drug effects
- Apoptosis/physiology
- Arteriosclerosis/enzymology
- Arteriosclerosis/pathology
- Arteriosclerosis/prevention & control
- Catheterization/adverse effects
- Cell Division/drug effects
- Cell Division/physiology
- Cells, Cultured
- Disease Models, Animal
- Enzyme Activation/drug effects
- Enzyme Activation/physiology
- Enzyme Inhibitors/pharmacology
- Enzyme Inhibitors/therapeutic use
- Flavonoids/administration & dosage
- Flavonoids/pharmacology
- Flavonoids/therapeutic use
- Iliac Artery/drug effects
- Iliac Artery/enzymology
- Iliac Artery/injuries
- Infusions, Intralesional
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 1/physiology
- Mitogen-Activated Protein Kinase 3
- Mitogen-Activated Protein Kinases/metabolism
- Mitogen-Activated Protein Kinases/physiology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Muscle, Smooth, Vascular/pathology
- Rabbits
- Tunica Intima/drug effects
- Tunica Intima/enzymology
- Tunica Intima/metabolism
- Tunica Intima/pathology
Collapse
Affiliation(s)
- Giuseppa Gennaro
- Department of Cardiovascular Research, Centre Hospitalier de l'Université de Montréal, Montréal, Québec, Canada
| | | | | | | | | | | | | |
Collapse
|
25
|
Yeo EJ, Park SC. Age-dependent agonist-specific dysregulation of membrane-mediated signal transduction: emergence of the gate theory of aging. Mech Ageing Dev 2002; 123:1563-78. [PMID: 12470894 DOI: 10.1016/s0047-6374(02)00092-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Although a general mechanism for the limited responsiveness of senescent cells has yet to be established, reduced responsiveness may in part be ascribed to deficits in the apparatus required for cell surface receptor-mediated signal transduction. Age-related changes of receptor-mediated signal transduction occur at many levels, and are known to include quantitative and qualitative changes in growth factor receptors, G-protein coupled receptors, and many other downstream signaling molecules. Here, we emphasize the prime role of the cellular surface in the perception and transmission of external stimuli in response to the aging process. As major means of cellular signal transduction, the receptor tyrosine kinase (RTK) system and the G protein-coupled receptor (GPCR) system of senescent cells were investigated. We observed that the RTK system was severely damaged, while the GPCR system was only partially inactivated by aging. These results suggest that the agonist-dependent dysregulation of and imbalance of signal transduction pathways might be responsible for the functional deterioration of senescent cells, and indicate a possibility of the functional recovery of senescent cells through agonist-specific signal system activation. Moreover, those data evoke the emerging concept that the senescent phenotype may be modulated by the membrance-associated signal system, implying the gate theory of aging.
Collapse
Affiliation(s)
- Eui-Ju Yeo
- Department of Biochemistry, Gachon Medical School, Inchon 417-840, South Korea.
| | | |
Collapse
|
26
|
Holbrook NJ, Ikeyama S. Age-related decline in cellular response to oxidative stress: links to growth factor signaling pathways with common defects. Biochem Pharmacol 2002; 64:999-1005. [PMID: 12213598 DOI: 10.1016/s0006-2952(02)01169-3] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Accumulation of oxidative damage is believed to be a major contributor to the decline in physiologic function that characterizes mammalian aging, and recent studies suggest that how well you respond to acute oxidative stress is an important factor in determining longevity. Oxidant injury elicits a wide spectrum of responses ranging from proliferation to cell death. The particular outcome observed largely reflects the severity of the stress encountered and the relative degree of activation of various signal transduction pathways aimed at enhancing survival or inducing cell death. Herein we examine the relationship between pathways important in supporting cell survival in response to oxidant injury and those involved in regulating proliferation. We review evidence indicating that [Curr. Opin. Cell Biol. 10 (1998) 248] common pathways are indeed involved in regulating these responses, and [Physiol. Rev. 82 (2002) 47] alterations in shared signaling events likely account for the age-related decline in the ability of cells to respond to both proliferative signals and oxidant stimuli.
Collapse
Affiliation(s)
- Nikki J Holbrook
- Section of Geriatrics, Department of Internal Medicine, Yale University School of Medicine, P.O. Box 208025, New Haven, CT 06520-8025, USA.
| | | |
Collapse
|
27
|
Li M, Torres C, Acuña-Castillo C, Walter R, Gardner EM, Murasko DM, Sierra F. Defect in ERK2 and p54(JNK) activation in aging mouse splenocytes. J Gerontol A Biol Sci Med Sci 2002; 57:B41-7. [PMID: 11818422 DOI: 10.1093/gerona/57.2.b41] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have previously reported on a defect in both extracellular signal-regulated protein kinase (ERK) and c-jun N-terminal kinase (JNK) mitogen-activated protein kinase (MAPK) activation in splenocytes obtained from old rats. In order to investigate whether these effects are conserved across species, we have now used mouse splenocytes to measure the effect of aging on the activation of the same two MAPK families: ERK and JNK. Our results demonstrate that, as in rats, both MAPK signal transduction pathways are affected by aging in mice, indicating the existence of a further defect located downstream of the receptor-proximal events. Whereas ERK1 and p46(JNK) activation were not significantly modified, the kinetics of both ERK2 and p54(JNK) activation and inactivation were affected in splenocytes from old animals. Specifically, by analyzing the kinetics of activation and inactivation of these enzymes, we found a nearly 50% decrease in the fold of activation of both ERK2 and p54(JNK). These defects result in an overall diminution of enzyme activities without changes in the steady-state levels of relevant proteins. The impaired activity of these two MAPK pathways is likely to play a role in the reduced expression of interleukin-2 and diminished lymphoproliferation observed in old animals.
Collapse
Affiliation(s)
- Min Li
- Center for Gerontological Research, MCP-Hahnemann University, Philadelphia, Pennsylvania, USA
| | | | | | | | | | | | | |
Collapse
|
28
|
Ikeyama S, Kokkonen G, Shack S, Wang XT, Holbrook NJ. Loss in oxidative stress tolerance with aging linked to reduced extracellular signal-regulated kinase and Akt kinase activities. FASEB J 2002; 16:114-6. [PMID: 11709495 DOI: 10.1096/fj.01-0409fje] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Oxidative stress is believed to be an important factor in the development of age-related diseases, and studies in lower organisms have established links between oxidative stress tolerance and longevity. We have hypothesized that aging is associated with a reduced ability to mount acute host defenses to oxidant injury, which increases the vulnerability of aged cells to stress. We tested this hypothesis by using primary hepatocytes from young (4-6 months) and aged (24-26 months) rats. Old hepatocytes were more sensitive to H2O2-induced apoptosis than were young cells. Lower survival is associated with reduced activations of extracellular signal-regulated kinase (ERK) and Akt kinase, both of which protect against oxidant injury. That reduced ERK and Akt activities contribute to lower survival of aged cells was supported by additional findings. First, pharmacologic inhibition of ERK and Akt activation in young cells markedly increased their sensitivity to H2O2. Second, caloric restriction, which increases rodent life span and delays the onset of many age-related declines in physiologic function, prevented loss in ERK and Akt activation by H2O2 and enhanced survival of old hepatocytes to levels similar to those of young cells. Strategies aimed at boosting these host responses to acute oxidant injury could have significant anti-aging benefits.
Collapse
Affiliation(s)
- Shizuo Ikeyama
- Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, Baltimore, Maryland 21224, USA
| | | | | | | | | |
Collapse
|
29
|
Nagata K, Izawa I, Inagaki M. A decade of site- and phosphorylation state-specific antibodies: recent advances in studies of spatiotemporal protein phosphorylation. Genes Cells 2001; 6:653-64. [PMID: 11532025 DOI: 10.1046/j.1365-2443.2001.00454.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
From 1990 to 2001, numerous site- and phosphorylation state-specific antibodies have been developed and many are now commercially available. These antibodies have facilitated understanding of the cytoskeletal organization, signal transduction and transcriptional mechanisms as well as clinical diseases. This review is an attempt to cover all these aspects.
Collapse
Affiliation(s)
- K Nagata
- Division of Biochemistry, Aichi Cancer Center Research Institute, 1-1 Kanokoden, Chikusa-ku, Nagoya, Aichi 464-8681, Japan
| | | | | |
Collapse
|
30
|
Wheaton K, Sampsel K, Boisvert FM, Davy A, Robbins S, Riabowol K. Loss of functional caveolae during senescence of human fibroblasts. J Cell Physiol 2001; 187:226-35. [PMID: 11268002 DOI: 10.1002/jcp.1071] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Primary human fibroblasts have a finite replicative lifespan in culture that culminates in a unique state of growth arrest, termed senescence that is accompanied by distinct morphological and biochemical alterations. Senescent cell responses to extracellular stimuli are believed to be altered at a point after receptors are bound by ligand, leading to improper integration of the signals which initiate DNA replication. In this study we demonstrate that one of the key organizing membrane microdomains for receptor signaling, caveolae, are absent in senescent cells. A comparison of young and senescent cells indicated that senescent cells contained a higher total amount of caveolins 1 and 2 but had significantly less of both proteins in the caveolar fraction. Additionally, caveolar fractions from senescent cells completely lacked the tyrosine-kinase activity associated with functional caveolae. Furthermore, old cells had little caveolar protein exposed to the outer plasma membrane as estimated by using an in vivo biotinylation assay and no detectable caveolin 1 on the cell surface when processed for immunofluoresence and confocal microscopy. Together, these data suggest that a fundamental loss of signal integration at the plasma membrane of senescent cells is due to the loss of signaling competent caveolae.
Collapse
Affiliation(s)
- K Wheaton
- Department of Biochemistry and Molecular Biology, Southern Alberta Cancer Centre, University of Calgary, Heritage Medical Research Building, Calgary Alberta, Canada
| | | | | | | | | | | |
Collapse
|
31
|
Park WY, Cho KA, Park JS, Kim DI, Park SC. Attenuation of EGF signaling in senescent cells by caveolin. Ann N Y Acad Sci 2001; 928:79-84. [PMID: 11795531 DOI: 10.1111/j.1749-6632.2001.tb05638.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
One of the characteristics of senescent cells is unresponsiveness to external stimuli like EGF. Although they have a normal level of receptors and downstream signaling molecules, EGF cannot induce the activation of Erk kinases and DNA synthesis in senescent cells as much as in young cells. Caveolin proteins directly interact with signaling molecules including EGF receptor and suppress the activation of EGFR upon EGF stimulation. We found that Erk activation after EGF stimulation in senescent human diploid fibroblasts was down-regulated. Those senescent cells showed an increased level of three isoforms of caveolin proteins. This change seems to lie in transcriptional control in senescent cells. We also demonstrated up-regulated caveolin proteins were co-localized with EGFR proteins in detergent-insoluble fractions. From these results, we suggest that the up-regulated expression of caveolin might explain the unresponsiveness of senescent fibroblasts to EGF stimulation.
Collapse
Affiliation(s)
- W Y Park
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, Korea
| | | | | | | | | |
Collapse
|
32
|
Hermanns HM, Radtke S, Schaper F, Heinrich PC, Behrmann I. Non-redundant signal transduction of interleukin-6-type cytokines. The adapter protein Shc is specifically recruited to rhe oncostatin M receptor. J Biol Chem 2000; 275:40742-8. [PMID: 11016927 DOI: 10.1074/jbc.m005408200] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The common use of the cytokine receptor gp130 has served as an explanation for the extremely redundant biological activities exerted by interleukin (IL)-6-type cytokines. Indeed, hardly any differences in signal transduction initiated by these cytokines are known. In the present study, we demonstrate that oncostatin M (OSM), but not IL-6 or leukemia inhibitory factor, induces tyrosine phosphorylation of the Shc isoforms p52 and p66 and their association with Grb2. Concomitantly, OSM turns out to be a stronger activator of ERK1/2 MAPKs. Shc is recruited to the OSM receptor (OSMR), but not to gp130. Binding involves Tyr(861) of the OSMR, located within a consensus binding sequence for the Shc PTB domain. Moreover, Tyr(861) is essential for activation of ERK1/2 and for full activation of the alpha(2)-macroglobulin promoter, but not for an exclusively STAT-responsive promoter. This study therefore provides evidence for qualitative differential signaling mechanisms exerted by IL-6-type cytokines.
Collapse
Affiliation(s)
- H M Hermanns
- Institut für Biochemie, Universitätsklinikum der Rheinisch-Westfälischen Technischen Hochschule Aachen, Pauwelsstr. 30, 52074 Aachen, Germany
| | | | | | | | | |
Collapse
|
33
|
Gentili C, de Boland AR. Age-related decline in mitogen-activated protein kinase phosphorylation in PTH-stimulated rat enterocytes. Exp Gerontol 2000; 35:1003-15. [PMID: 11121686 DOI: 10.1016/s0531-5565(00)00133-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
In the present study we analyzed whether parathyroid hormone (rPTH[1-34]; PTH) stimulates the tyrosine phosphorylation of the growth-related protein mitogen-activated protein (MAP) kinases (p42/44-MAPK), also known as extracellular signal-regulated kinases (ERK1/2), in duodenal enterocytes isolated from young (3months) and aged (24months) rats. Western blot analysis revealed that PTH rapidly stimulates MAPK phosphorylation. The hormone effects on MAPK were evident within 30s, peaking at 1min (4-fold). PTH response was dose-dependent (10(-11)-10(-7) M) with maximal stimulation achieved at 10(-9)-10(-8) M. PTH-induced MAPK phosphorylation was effectively suppressed by the tyrosine-kinase inhibitors, genistein (100microM) and herbimycin (2microM). Moreover, the tyrosine phosphorylation and activation of MAPK was dependent on Src kinase, since PP1 (10 and 20microM), a specific Src family tyrosine-kinase inhibitor, blocked PTH-induced MAPK activation. With aging, the response to PTH was significantly reduced. However, The amount of basal protein expression determined by Western blot analysis for MAPK was not different in the enterocytes from young and aged rats. In conclusion, the results obtained in this work expand our knowledge on the mechanism of action of PTH in duodenal cells, revealing that protein tyrosine phosphorylation is linked to the PTH regulation of enterocyte MAPK activation, and that this mechanism is impaired with aging. Understanding the molecular mechanisms for the age-related differences in PTH signaling will require more information about the subtle mechanisms that modulate the PTH receptor-MAPK signaling pathway.
Collapse
Affiliation(s)
- C Gentili
- Departamento de Biologia, Bioquímica & Farmacia, Universidad Nacional del Sur, Bahia Blanca 8000, Argentina
| | | |
Collapse
|
34
|
Shiraha H, Gupta K, Drabik K, Wells A. Aging fibroblasts present reduced epidermal growth factor (EGF) responsiveness due to preferential loss of EGF receptors. J Biol Chem 2000; 275:19343-51. [PMID: 10764734 DOI: 10.1074/jbc.m000008200] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Wound healing is compromised in aging adults in part due to decreased responsiveness of fibroblasts to extracellular signals. However, the cellular mechanisms underlying this phenomenon are not known. Aged dermal fibroblasts with reduced remaining replicative capacities demonstrated decreased epidermal growth factor (EGF)-induced cell migrative and cell proliferative capacities, as reported previously. Thus, as cells approach senescence, programmed in vivo or in vitro, EGF responsiveness is preferentially lost. To define the rate-limiting signaling event, we found that the activity of two different EGF receptor (EGFR)-signaling pathways to cell migration (phospholipase-C gamma) and/or mitogenesis (extracellular signal/regulated-mitogen-activated kinases) were decreased in near senescent cells despite unchanged levels of effector molecules. Aged cells presented decreased levels of EGFR, although insulin receptor and transferrin receptor levels were relatively unchanged. EGFR mRNA levels and production of new transcripts decreased during aging, suggesting that this preferential loss of EGFR was due to diminished production, which more than counteracts the reduced ligand-induced receptor loss. Since these data suggested that the decrement in EGF was rate-limiting, higher levels of EGFR were established in near senescent cells by electroporation of EGFR cDNA. These cells presented higher levels of EGFR and recovered their EGF-induced migration and proliferation responsiveness. Thus, the defect in EGF responsiveness of aged dermal fibroblasts is secondary to reduced EGFR message transcription. Our experimental model suggests that EGFR gene delivery might be an effective future therapy for compromised wound healing.
Collapse
Affiliation(s)
- H Shiraha
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15261 and Department of Pathology, University of Alabama, Birmingham, Alabama 35294-0007, USA
| | | | | | | |
Collapse
|
35
|
Hutter D, Yo Y, Chen W, Liu P, Holbrook NJ, Roth GS, Liu Y. Age-related decline in Ras/ERK mitogen-activated protein kinase cascade is linked to a reduced association between Shc and EGF receptor. J Gerontol A Biol Sci Med Sci 2000; 55:B125-34. [PMID: 10795716 DOI: 10.1093/gerona/55.3.b125] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Numerous studies have demonstrated that the proliferative capacity of cells declines with age. Using rat primary hepatocytes as a model system, we recently demonstrated that this age-related decline in the proliferative response to mitogenic stimulation is associated with decreased activities of both extracellular signal-regulated kinase (ERK) and p70 S6 kinase (p70(S6k)). To unravel the molecular basis for age-related defects in the ERK pathway, we have now characterized the upstream signaling events that occur after epidermal growth factor (EGF) stimulation in young and aged hepatocytes. As previously noted for ERK, the activities of both MEK (the kinase immediately upstream of ERK) and Ras following EGF stimulation were significantly lower in aged hepatocytes. An examination of the EGF receptor (EGFR) revealed a similar amount of EGFR in the two age groups. Likewise, EGFR and Shc, an adaptor protein that plays a crucial role in linking EGFR to Ras activation, underwent tyrosine phosphorylation to a similar degree in both young and aged hepatocytes. However, in aged cells Shc was unable to form stable complexes with EGFR after EGF stimulation. Our results suggest that a decrease in the association between Shc and EGFR in aged cells underlies the age-related declines in the ERK signaling cascade and in proliferative capacity.
Collapse
Affiliation(s)
- D Hutter
- Laboratory of Biological Chemistry, National Institute on Aging, Gerontology Research Center, Baltimore, Maryland 21224, USA
| | | | | | | | | | | | | |
Collapse
|
36
|
Age-dependent decline in EGF-induced signaling is independent of intracellular thiols. J Am Aging Assoc 1999; 22:167-73. [DOI: 10.1007/s11357-999-0019-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|