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Merino-Wong M, Niemeyer BA, Alansary D. Plasma Membrane Calcium ATPase Regulates Stoichiometry of CD4 + T-Cell Compartments. Front Immunol 2021; 12:687242. [PMID: 34093590 PMCID: PMC8175910 DOI: 10.3389/fimmu.2021.687242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 05/04/2021] [Indexed: 11/13/2022] Open
Abstract
Immune responses involve mobilization of T cells within naïve and memory compartments. Tightly regulated Ca2+ levels are essential for balanced immune outcomes. How Ca2+ contributes to regulating compartment stoichiometry is unknown. Here, we show that plasma membrane Ca2+ ATPase 4 (PMCA4) is differentially expressed in human CD4+ T compartments yielding distinct store operated Ca2+ entry (SOCE) profiles. Modulation of PMCA4 yielded a more prominent increase of SOCE in memory than in naïve CD4+ T cell. Interestingly, downregulation of PMCA4 reduced the effector compartment fraction and led to accumulation of cells in the naïve compartment. In silico analysis and chromatin immunoprecipitation point towards Ying Yang 1 (YY1) as a transcription factor regulating PMCA4 expression. Analyses of PMCA and YY1 expression patterns following activation and of PMCA promoter activity following downregulation of YY1 highlight repressive role of YY1 on PMCA expression. Our findings show that PMCA4 adapts Ca2+ levels to cellular requirements during effector and quiescent phases and thereby represent a potential target to intervene with the outcome of the immune response.
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Affiliation(s)
| | | | - Dalia Alansary
- Molecular Biophysics, Saarland University, Homburg, Germany
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2
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Grover AK. Sodium-Calcium Exchanger in Pig Coronary Artery. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2016; 78:145-170. [PMID: 28212796 DOI: 10.1016/bs.apha.2016.06.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This review focuses on the sodium-calcium exchangers (NCX) in the left anterior descending coronary artery smooth muscle. Bathing tissues in Na+-substituted solutions caused them to contract. In cultured smooth muscle cells, it increased the cytosolic Ca2+ concentration and extracellular entry of 45Ca2+. All three activities were attributed to NCX since they were inhibited by NCX inhibitors. The tissues also expressed the sarco/endoplasmic reticulum (SER) Ca2+ pump SERCA2b whose activity was much greater than that of NCX. Inhibiting SERCA2b with thapsigargin decreased the NCX-mediated 45Ca2+ accumulation by the cells. The decrease was not observed in cells loaded with the Ca2+-chelator BAPTA. The results are consistent with a limited diffusional space model with a proximity between NCX and SERCA2b. NCX molecules appear to be colocalized with the subsarcolemmal SERCA2b based on studies on membrane flotation experiments and microscopic fluorescence imaging of antibody-labeled cells. Thapsigargin inhibition of SERCA2b moved NCX even closer to SER. This provides a model for the NCX-mediated Ca2+ refilling of SER in the arterial smooth muscle. The model for the NCX-mediated refilling of the depleted SER proposed for smooth muscle did not apply to endothelium in which NCX levels were greater and SERCA levels were lower than in smooth muscle. The effect of thapsigargin on the NCX-mediated Ca2+ accumulation which was observed in smooth muscle was absent in the endothelium. We propose that the coupling between NCX and smooth muscle may be tissue dependent.
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Affiliation(s)
- A K Grover
- McMaster University, Hamilton, ON, Canada.
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Kiang JG, Smith JT, Agravante NG. Geldanamycin analog 17-DMAG inhibits iNOS and caspases in gamma-irradiated human T cells. Radiat Res 2009; 172:321-30. [PMID: 19708781 DOI: 10.1667/rr1585.1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Inducible nitric oxide synthase (iNOS) expression and NO production increase after radiation exposure. We showed previously that inhibiting iNOS expression prevents hemorrhage injury; we therefore investigated whether inhibiting iNOS expression also limits radiation injury. Human Jurkat T cells were exposed to gamma radiation (2, 4, 6 or 8 Gy), and cell lysates were collected for analysis at selected times afterward. Radiation exposure increased iNOS expression within 4 h postirradiation by increasing the levels of the iNOS transcription factors NF-kappaB and KLF6. By 24 h postirradiation cell viability was reduced. In these cells, NO production, lipid peroxidation, protein nitration, apoptosomes (formed by cytochrome c, caspase 9 and Apaf-1), and caspase 3 activity were significantly elevated, suggesting that the iNOS pathway had been activated. Treatment with the iNOS inhibitors 17-DMAG or L-NIL-6 24 h prior to irradiation limited these changes, as did treatment with iNOS siRNA to silence the iNOS gene. These results suggest radiation injury involves the iNOS pathway, and iNOS-mediated NO produced endogenously in the T cell alters overall T-cell function and results in apoptosis and cell lethality. Control of iNOS expression may represent a useful approach for protecting T cells from radiation injury.
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Affiliation(s)
- Juliann G Kiang
- Department of Radiation Biology, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20889-5603, USA.
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Kiang JG, Krishnan S, Lu X, Li Y. Inhibition of inducible nitric-oxide synthase protects human T cells from hypoxia-induced apoptosis. Mol Pharmacol 2007; 73:738-47. [PMID: 18079278 DOI: 10.1124/mol.107.041079] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Sodium cyanide-induced chemical hypoxia triggers a series of biochemical alterations leading to apoptosis in many cell types, including T cells. It is known that chemical hypoxia promotes inducible nitric-oxide synthase (iNOS) gene transcription by activating its transcription factors. To determine whether iNOS and NO production are responsible for chemical hypoxia-induced apoptosis, we exposed human Jurkat T cells to sodium cyanide in the presence or absence of iNOS inhibitors. We found that iNOS expression is necessary for hypoxia-induced lipid peroxidation and leukotriene B(4) generation. The inhibition of iNOS limited T-cell apoptosis by decreasing the activity of caspase-3 without affecting the expression of Fas/Apo-1/CD95 on the surface membrane of T cells. These data suggest iNOS-mediated NO produced endogenously in the T cell alters overall T-cell function and results in apoptosis. Proper control of iNOS expressed in the T cell may represent a useful approach to immunomodulation.
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Affiliation(s)
- Juliann G Kiang
- Armed Forces Radiobiology Research Institute, Bldg. 46, Room 2423, 8901 Wisconsin Ave., Bethesda, MD 20889-5603, USA.
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Kokura S, Adachi S, Manabe E, Mizushima K, Hattori T, Okuda T, Nakabe N, Handa O, Takagi T, Naito Y, Yoshida N, Yoshikawa T. Whole body hyperthermia improves obesity-induced insulin resistance in diabetic mice. Int J Hyperthermia 2007; 23:259-65. [PMID: 17523018 DOI: 10.1080/02656730601176824] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
AIM In this study, we examined the efficacy of whole body hyperthermia (WBH) on obesity-induced insulin resistance in diabetic mice. METHODS Male db/db mice were treated with WBH 3 times per week for 12 weeks. The rectal temperature of mice reached 38.0 degrees C 5 min after heating, and was kept at 38.0 degrees C for 30 min. At the end of each week, tail snip glucose levels were determined under fasting conditions. The GLUT-4 gene expression of muscle tissue was analyzed by real-time PCR. RESULTS (1) WBH-treated db/db mice showed a significant decrease in fasting blood glucose level as compared with untreated db/db mice (p < 0.01). (2) Plasma insulin levels in untreated db/db mice at the age of 10 weeks were significantly increased compared with those of db/+ mice (p < 0.0001). On the other hand, the reduction (31%) in insulin levels in WBH-treated mice indicated improved insulin sensitivity. (3) The ability of WBH to increase insulin sensitivity was further established in glucose tolerance tests and insulin tolerance tests. (4) Urine albumin of db/db mice significantly increased compared with those of db/+ mice at 18 weeks of age (p < 0.001). This increase in urinary albumin was significantly inhibited by WBH (p < 0.01). (5) WBH up-regulated the expression of GLUT4 mRNA in skeletal muscle. CONCLUSION Although the mechanisms have not yet been completely investigated, WBH may provide a new therapeutic or preventive modality against obesity-related diseases such as T2DM and metabolic or insulin resistance syndrome.
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MESH Headings
- Albuminuria/physiopathology
- Animals
- Blood Glucose/metabolism
- Diabetes Mellitus, Type 2/physiopathology
- Diabetes Mellitus, Type 2/therapy
- Disease Models, Animal
- Fatty Acids, Nonesterified/blood
- Gene Expression Regulation
- Glucose Transporter Type 4/genetics
- Glucose Transporter Type 4/metabolism
- Hyperthermia, Induced
- Insulin/blood
- Insulin Resistance/physiology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Inbred Strains
- Muscle, Skeletal/metabolism
- Obesity/physiopathology
- Obesity/therapy
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Triglycerides/blood
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Affiliation(s)
- Satoshi Kokura
- Biomedical Safety Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
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Khazzaka A, Figwer P, Poirel M, Serrar M, Franck M. Hsp70 response in pigs is affected by their Halothane genotypes after heat stress. J Therm Biol 2006. [DOI: 10.1016/j.jtherbio.2006.08.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Martucci C, Franchi S, Lattuada D, Panerai AE, Sacerdote P. Differential involvement of RelB in morphine-induced modulation of chemotaxis, NO, and cytokine production in murine macrophages and lymphocytes. J Leukoc Biol 2006; 81:344-54. [PMID: 17023558 DOI: 10.1189/jlb.0406237] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Acute morphine impairs innate and acquired immunity. The mechanisms involved in immunosuppression have not been well defined yet. The transcription factor NF-kappaB is a central regulator of immunity, and of the NF-kappaB family, RelB is particularly involved in the expression of genes important in immune responses. We investigated the involvement of RelB in morphine-induced immunosuppression in mice deficient for the RelB factor. RelB-/- mice and wild-type (WT) controls were injected s.c. with morphine 20 mg/Kg, and 1 h later, immune parameters were evaluated. Morphine significantly reduced macrophage production of the proinflammatory cytokines IL-1beta, TNF-alpha, and IL-12 in WT animals, and the drug failed to diminish the production of these cytokines in the RelB-/- mice. In contrast, the anti-inflammatory cytokine IL-10 was similarly affected in the two strains. Macrophage NO production was modulated by morphine in WT animals only, and morphine similarly decreased macrophage chemotaxis in the presence or in the absence of RelB. When Th1 and Th2 cytokines were evaluated, we observed a clear morphine-induced reduction of IL-2 and IFN-gamma production by WT splenocytes, whereas no effect of the drug was observed in RelB-/- mice. On the contrary, the production of the Th2 cytokines IL-4 and IL-10 was lessened to the same degree by morphine in WT and RelB-/- mice. In conclusion, our data suggest that RelB is an important target for morphine modulation of proinflammatory and Th1 cytokines. They also indicate that morphine uses multiple intracellular pathways to exert its generalized immunosuppression.
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Affiliation(s)
- Cataldo Martucci
- Department of Pharmacology, University of Milano, Via Vanvitelli 32, 20129 Milano, Italy
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8
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Broadbent S, Gass G. Effects of endurance training on intracellular calcium concentration in T lymphocytes. Eur J Appl Physiol 2006; 98:242-9. [PMID: 16906414 DOI: 10.1007/s00421-006-0268-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/27/2006] [Indexed: 10/24/2022]
Abstract
The purpose of the present study was to determine whether 12 months of endurance training reduced [Ca2+]i in T helper (CD4+) lymphocytes in trained (TR) men compared to untrained (UT). Fourteen trained (Ironman triathletes) and nine untrained (sedentary) men volunteered for the study. The TR group averaged 12 km of swimming, 300 km of cycling and 60 km of running per week during the year. Resting blood samples were taken from TR (VO(2peak) 64 +/- 2 ml kg(-1) min(-1)) and UT (VO(2peak) 42 +/- 2 ml kg(-1) min(-1)) subjects every 4 weeks for 52 weeks (October 1, 1999-October 1, 2000). Leukocyte concentration was measured using a full blood count. Unstimulated CD4+ lymphocytes were separated and analysed for changes in free ([Ca2+]i) and total ([Ca2+]t) calcium using flow cytometry. There were no significant differences in leukocyte concentration between UT and TR groups. There were significant differences between TR and UT in [Ca2+]i (October B and November), and [Ca2+]t (January and March). There were also significant sequential monthly changes in both [Ca2+]i and [Ca2+]t for TR and UT groups during the study. Significant increases in [Ca2+]i and [Ca2+]t during summer (January and March) for both TR and UT groups suggest an increase in intracellular signalling during hot weather. [Ca2+]i and [Ca2+]t were significantly lower in TR lymphocytes during November and March, suggesting that endurance training during warmer months may decrease [Ca2+]i through altered intracellular signalling, possibly to maintain lymphocyte function during heat stress.
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Affiliation(s)
- Suzanne Broadbent
- Institute of Food, Nutrition and Human Health, Massey University, Private Bag 756, Wellington, New Zealand.
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Abstract
Aging is characterized by a stochastic accumulation of molecular damage, progressive failure of maintenance and repair, and consequent onset of age-related diseases. Applying hormesis in aging research and therapy is based on the principle of stimulation of maintenance and repair pathways by repeated exposure to mild stress. In a series of experimental studies we have shown that repetitive mild heat stress has anti-aging hormetic effects on growth and various other cellular and biochemical characteristics of human skin fibroblasts undergoing aging in vitro. These effects include the maintenance of stress protein profiles, reduction in the accumulation of oxidatively and glycoxidatively damaged proteins, stimulation of the proteasomal activities for the degradation of abnormal proteins, improved cellular resistance to ethanol, hydrogen peroxide and ultraviolet-B rays, and enhanced levels of various antioxidant enzymes. Anti-aging hormetic effects of mild heat shock appear to be facilitated by reducing protein damage and protein aggregation by activating internal antioxidant, repair and degradation processes.
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Affiliation(s)
- Suresh I S Rattan
- Laboratory of Cellular Ageing, Danish Centre for Molecular Gerontology, Department of Molecular Biology, University of Aarhus, Gustav Wieds Vej 10C, Aarhus-C, Denmark.
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Kiang JG, Ives JA, Jonas WB. External bioenergy-induced increases in intracellular free calcium concentrations are mediated by Na+/Ca2+ exchanger and L-type calcium channel. Mol Cell Biochem 2005; 271:51-9. [PMID: 15881655 DOI: 10.1007/s11010-005-3615-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
External bioenergy (EBE, energy emitted from a human body) has been shown to increase intracellular calcium concentration ([Ca2+]i, an important factor in signal transduction) and regulate the cellular response to heat stress in cultured human lymphoid Jurkat T cells. In this study, we wanted to elucidate the underlying mechanisms. A bioenergy specialist emitted bioenergy sequentially toward tubes of cultured Jurkat T cells for one 15-minute period in buffers containing different ion compositions or different concentrations of inhibitors. [Ca2+], was measured spectrofluorometrically using the fluorescent probe fura-2. The resting [Ca2+]i in Jurkat T cells was 70 +/- 3 nM (n = 130) in the normal buffer. Removal of external calcium decreased the resting [Ca2+]i to 52 +/- 2 nM (n = 23), indicating that Ca2+ entry from the external source is important for maintaining the basal level of [Ca2+]i. Treatment of Jurkat T cells with EBE for 15 min increased [Ca2+]i by 30 +/- 5% (P < 0.05, Student t-test). The distance between the bioenergy specialist and Jurkat T cells and repetitive treatments of EBE did not attenuate [Ca2+]i responsiveness to EBE. Removal of external Ca2+ or Na+, but not Mg2+, inhibited the EBE-induced increase in [Ca2+]i. Dichlorobenzamil, an inhibitor of Na+/Ca2+ exchangers, also inhibited the EBE-induced increase in [Ca2+]i in a concentration-dependent manner with an IC50 of 0.11 +/- 0.02 nM. When external [K+] was increased from 4.5 mM to 25 mM, EBE decreased [Ca2+]i. The EBE-induced increase was also blocked by verapamil, an L-type voltage-gated Ca2+ channel blocker. These results suggest that the EBE-induced [Ca2+]i increase may serve as an objective means for assessing and validating bioenergy effects and those specialists claiming bioenergy capability. The increase in [Ca2+]i is mediated by activation of Na+/Ca2+ exchangers and opening of L-type voltage-gated Ca2+ channels.
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Affiliation(s)
- Juliann G Kiang
- Department of Cellular Injury, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Room 1N07, Silver Spring, MD 20910-7500, USA.
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Annunziato L, Pignataro G, Di Renzo GF. Pharmacology of Brain Na+/Ca2+Exchanger: From Molecular Biology to Therapeutic Perspectives. Pharmacol Rev 2004; 56:633-54. [PMID: 15602012 DOI: 10.1124/pr.56.4.5] [Citation(s) in RCA: 254] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
In the last two decades, there has been a growing interest in unraveling the role that the Na+/Ca2+ exchanger (NCX) plays in the function and regulation of several cellular activities. Molecular biology, electrophysiology, genetically modified mice, and molecular pharmacology have helped to delve deeper and more successfully into the physiological and pathophysiological role of this exchanger. In fact, this nine-transmembrane protein, widely distributed in the brain and in the heart, works in a bidirectional way. Specifically, when it operates in the forward mode of operation, it couples the extrusion of one Ca2+ ion with the influx of three Na+ ions. In contrast, when it operates in the reverse mode of operation, while three Na+ ions are extruded, one Ca2+ enters into the cells. Different isoforms of NCX, named NCX1, NCX2, and NCX3, have been described in the brain, whereas only one, NCX1, has been found in the heart. The hypothesis that NCX can play a relevant role in several pathophysiological conditions, including hypoxia-anoxia, white matter degeneration after spinal cord injury, brain trauma and optical nerve injury, neuronal apoptosis, brain aging, and Alzheimer's disease, stems from the observation that NCX, in parallel with selective ion channels and ATP-dependent pumps, is efficient at maintaining intracellular Ca2+ and Na+ homeostasis. In conclusion, although studies concerning the involvement of NCX in the pathological mechanisms underlying brain injury during neurodegenerative diseases started later than those related to heart disease, the availability of pharmacological agents able to selectively modulate each NCX subtype activity and antiporter mode of operation will provide a better understanding of its pathophysiological role and, consequently, more promising approaches to treat these neurological disorders.
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Affiliation(s)
- L Annunziato
- Division of Pharmacology, Department of Neuroscience, School of Medicine, Federico II University of Naples, Via S. Pansini, 5-80131 Naples, Italy.
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Missan S, McDonald TF. Cardiac Na+-Ca2+ exchanger current induced by tyrphostin tyrosine kinase inhibitors. Br J Pharmacol 2004; 143:943-51. [PMID: 15545291 PMCID: PMC1575963 DOI: 10.1038/sj.bjp.0706011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Tyrosine kinase (TK) inhibitors genistein and tyrphostin A23 (A23) inhibited Ca(2+) currents in guinea-pig ventricular myocytes investigated under standard whole-cell conditions (K(+)-free Tyrode's superfusate; EGTA-buffered (pCa-10.5) Cs(+) dialysate). However, the inhibitors (100 microM) also induced membrane currents that reversed between -40 and 0 mV, and the objective of the present study was to characterize these currents. Genistein-induced current behaved like Cl(-) current, and was unaffected by either the addition of divalent cations (0.5 mM Cd(2+); 3 mM Ni(2+)) that block the Na(+)-Ca(2+) exchanger (NCX), or the removal of external Na(+) and Ca(2+). A23-induced current was independent of Cl(-) driving force, and strongly suppressed by addition of Cd(2+) and Ni(2+), and by removal of either external Na(+) or Ca(2+). These and other results suggested that A23 activated an NCX current driven by submembrane Na(+) and Ca(2+) concentrations higher than those in the bulk cytoplasm. Improved control of intracellular Na(+) and Ca(2+) concentrations was obtained by suppressing cation influx (10 microM verapamil) and raising dialysate Na(+) to 7 mM and dialysate pCa to 7. Under these conditions, stimulation by A23 was described by the Hill equation with EC(50) 68 +/- 4 microM and coefficient 1.1, tyrphostin A25 was as effective as A23, and TK-inactive tyrphostin A1 was ineffective. Phosphotyrosyl phosphatase inhibitor orthovanadate (1 mM) antagonized the action of 100 microM A23. The results suggest that activation of cardiac NCX by A23 is due to inhibition of genistein-insensitive TK.
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Affiliation(s)
- Sergey Missan
- Department of Physiology and Biophysics, Dalhousie University, 5859 University Avenue, Halifax, Nova Scotia, Canada B3H 4H7.
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Rattan SIS. Hormetic Mechanisms of Anti-Aging and Rejuvenating Effects of Repeated Mild Heat Stress on Human Fibroblasts in Vitro. Rejuvenation Res 2004; 7:40-8. [PMID: 15256044 DOI: 10.1089/154916804323105071] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The phenomenon of hormesis is represented by mild stress-induced stimulation of maintenance and repair pathways, resulting in beneficial effects for cells and organisms. We have reported that repeated mild heat stress (RMHS) has anti-aging hormetic effects on growth and various cellular and biochemical characteristics of human skin fibroblasts undergoing aging in vitro. These effects of RMHS include the maintenance of the stress protein profile, reduction in the accumulation of oxidatively and glycoxidatively damaged proteins, stimulation of the activities of the proteasome and its 11S activator, improvement in cellular resistance to ethanol, hydrogen peroxide, and ultraviolet rays, and increased antioxidative activity of the cells. We have also reported that RMHS prolongs the lifespan of Drosophila. Others have reported anti-aging and life prolonging effects of a wide variety of so-called stressors, such as pro-oxidants, aldehydes, calorie restriction, irradiation, heat shock, and hypergravity. Although molecular mechanisms of hormesis are yet to be elucidated, there are indications that relatively small hormetic effects become biologically amplified, resulting in significant improvement of cellular and organic functions and survival. Hormesis, therefore, can be an effective approach for modulating aging, for preventing or delaying the onset of age-related diseases, and for improving the quality of life in old age.
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Kiang JG, Bowman PD, Wu BW, Hampton N, Kiang AG, Zhao B, Juang YT, Atkins JL, Tsokos GC. Geldanamycin treatment inhibits hemorrhage-induced increases in KLF6 and iNOS expression in unresuscitated mouse organs: role of inducible HSP70. J Appl Physiol (1985) 2004; 97:564-9. [PMID: 15090481 DOI: 10.1152/japplphysiol.00194.2004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to determine whether hemorrhage affects the levels of a variety of stress-related proteins and whether changes can be inhibited by drugs reported to provide protection from ischemia and reperfusion injury. Male Swiss Webster mice were subjected to a 40% hemorrhage without resuscitation. Western blot analysis indicated that c-Jun (an AP-1 protein), Kruppel-like factor 6 (KFL6), and inducible nitric oxide synthase (iNOS) were upregulated sequentially in that order. Pretreatment of mice with geldanamycin (GA) 16 h before hemorrhage effectively inhibited the expression of the proteins KLF6 and iNOS, whereas caffeic acid phenethyl ester did not. GA pretreatment increased inducible heat shock protein (HSP) 70 but not HSP90 in both sham and hemorrhagic tissues. The overexpressed inducible HSP70 formed complexes with KLF6 and iNOS. These results suggest that GA may be therapeutically useful for reducing hemorrhage-induced injury when used as a presurgical treatment or when added to resuscitation fluids.
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Affiliation(s)
- Juliann G Kiang
- Department of Cellular Injury, Division of Military Casualty Research, Walter Reed Army Institute of Research, Silver Spring, MD 20910-7500, USA.
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Rattan SIS, Eskildsen-Helmond YEG, Beedholm R. Molecular mechanisms of anti-aging hormetic effects of mild heat stress on human cells. NONLINEARITY IN BIOLOGY, TOXICOLOGY, MEDICINE 2004; 2:105-116. [PMID: 19330126 PMCID: PMC2655703 DOI: 10.1080/15401420490464376] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In a series of experimental studies we have shown that repetitive mild heat stress has anti-aging hormetic effects on growth and various other cellular and biochemical characteristics of human skin fibroblasts undergoing aging in vitro. We have reported the hormetic effects of repeated challenge at the levels of maintenance of stress protein profile; reduction in the accumulation of oxidatively and glycoxidatively damaged proteins; stimulation of the proteasomal activities for the degradation of abnormal proteins; improved cellular resistance to ethanol, hydrogenperoxide, and ultraviolet-B rays; and enhanced levels of various antioxidant enzymes. We are now undertaking a detailed analysis of the signal transduction pathways to determine alterations in the phosphorylation and dephosphorylation states of extracellular signal-related kinase, c-Jun terminal kinase and p38 MAP-kinases as a measure of cellular responsiveness to mild and severe heat stress. Furthermore, we are also undertaking comparative studies using non-aging immortal cell lines, such as SV40-transformed human fibroblasts, spontaneous osteosarcoma cells, and telomerase-immortalized human bone marrow cells for establishing differences in normal and cancerous cells with respect to their responsiveness to mild and severe stresses.
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Affiliation(s)
- Suresh I S Rattan
- Danish Centre for Molecular Gerontology, Department of Molecular Biology, University of Aarhus, Aarhus, Denmark
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