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Using data from Schink et al. (2018), a large number of herbal extracts were assessed for their capacity to inducepro- and anti-inflammatory effects based on TLR4 expression normalized for cell viability in two immune cellmodels (i.e., HeLa-TLR4 transfected reporter cell line, and THP-1 monocytes) applying seven concentrations(0.01–3.0%). The analysis revealed that 70–80% of the extracts satisfying the a priori entry criteria also satisfieda priori evaluative criteria for hormetic concentration responses. These findings demonstrate that a large proportionof herbal extracts display hormetic dose responses in immune cells, indicating that hormetic mechanismsmediate pro- and anti-inflammatory processes and may provide a means to guide optimal dosing strategies. Theidentification of doses eliciting only anti-inflammatory therapeutic activity as well as the use of dose-variableherbal extracts in the treatment of inflammatory diseases will be challenging.

Although high levels of stress hormones are associated with well-known negative health outcomes, their low levels can have health-promoting effects by virtue of the phenomenon of mild stress-induced hormesis. We have studied the effects of a wide range (between 100 nmol/L and 150 μmol/L) of hydrocortisone (HC) on human bone marrow stem cells in vitro. Telomerase-immortalized human mesenchymal stem cells (hTERT-MSCs) were exposed to various doses of HC for different durations (1-6 days) and analyzed for survival and metabolic activity by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, for cell migratory ability by a wound-healing assay and for osteoblastic and adipogenic differentiation abilities in vitro. Our findings indicate that hTERT-MSCs exposed to HC resulted in a biphasic hormetic dose–response in some measures but not all. Although the mitochondrial and metabolic MTT activity assay clearly showed low-level stimulatory (between 0.1 and 1 µmol/L) and high-level inhibitory effects (from about 10 µmol/L onward), the cytostatic and differentiation-inducing effects were mostly linear at concentrations between 1 and 100 µmol/L. Further long-term studies will elucidate whether chronic or intermittent exposure of human cells to stress hormones has physiologically beneficial hormetic effects.

Oxidized, damaged and misfolded proteins accumulate during aging and contribute to impaired cell function and tissue homeodynamics. Damaged proteins are degraded by cellular clearance mechanisms like the 20S proteasome. Aging relates to low 20S proteasome function, whereas long-lived species show high levels. However, contradictory results exist depending on the tissue or cell type and it is unknown how the 20S proteasome functions in exceptionally old mice. The aim of this study was to investigate two proteasome activities (caspase-like and chymotrypsin-like) in several tissues (lung, heart, axillary lymph nodes, liver, kidney) and cells (peritoneal leukocytes) from adult (28 ± 4 weeks, n = 12), old (76 ± 4 weeks, n = 9) and exceptionally old (128 ± 4 weeks, n = 9) BALB/c female mice. The results show different age-related changes depending on the tissue and the activity considered, so there is no universal decline in proteasome function with age in female mice. Interestingly, exceptionally old mice displayed better maintained proteasome activities, suggesting that preserved 20S proteasome is associated with successful aging.

A promising strategy for maintaining a healthy and youthful phenotype during aging is that of mild stress-induced beneficial hormesis. The basis of hormesis lies in the molecular pathways of stress response, which are essential for the survival of a biological system by activation of maintenance and repair mechanisms in response to stress. Moderate physical exercise is the best example of a hormetin that brings about a wide range of health beneficial hormesis by first challenging the system. Similarly, other natural and synthetic hormetins can be incorporated in cosmeceutical formulations, and can help achieve benefits including maintenance of the skin structure and function. Several polyphenols, flavonoids and other components from spices, algae and other sources are potential hormetins that may act via hormesis. Stress response pathways that can be analyzed for screening potential hormetins for use in cosmetics and cosmeceuticals include heat shock response, autophagy, DNA damage response, sirtuin response, inflammatory response and oxidative stress response.

Mild stress-induced activation of stress response (SR) pathways, such as autophagy, heat shock response, oxidative SR, DNA damage response, and inflammatory response, can be potentially health beneficial. Using the model system of cellular ageing and replicative senescence in vitro, we have studied the ageing modulatory effects of the two conditions, rapamycin and serum starvation. Chronic exposure to 0.1, 1 and 10 nM rapamycin positively modulated the survival, growth, morphology, telomere length, DNA methylation levels, 8-oxo-dG level in DNA, N6-methyl-adenosine level in RNA, and ethanol stress tolerance of serially passaged normal human skin fibroblasts. Furthermore, episodic (once a week) serum starvation of human skin fibroblasts extended their replicative lifespan by about 22%, along with the maintenance of early passage youthful morphology even in late passage cultures. Although the results of this study may be considered preliminary, it can be inferred that intermittent and episodic induction of SR, rather than chronic up-regulation of SR, is more effective and applicable in the practice of hormesis for healthy ageing and longevity.

Lineage or cell of origin of cancers is often unknown and thus is not a consideration in therapeutic approaches. Alveolar rhabdomyosarcoma (aRMS) is an aggressive childhood cancer for which the cell of origin remains debated. We used conditional genetic mouse models of aRMS to activate the pathognomonic Pax3:Foxo1 fusion oncogene and inactivate p53 in several stages of prenatal and postnatal muscle development. We reveal that lineage of origin significantly influences tumor histomorphology and sensitivity to targeted therapeutics. Furthermore, we uncovered differential transcriptional regulation of the Pax3:Foxo1 locus by tumor lineage of origin, which led us to identify the histone deacetylase inhibitor entinostat as a pharmacological agent for the potential conversion of Pax3:Foxo1-positive aRMS to a state akin to fusion-negative RMS through direct transcriptional suppression of Pax3:Foxo1.

Leptomeningeal metastasis is a cause of morbidity and mortality in medulloblastoma, but the understanding of molecular mechanisms driving this process is nascent. In this study, we examined the secretory chemokine profile of medulloblastoma cells (DAOY) and a meningothelial cell line (BMEN1). Conditioned media (CM) of meningothelial cells increased adhesion, spreading and migration of medulloblastoma. VEGFA was identified at elevated levels in the CM from BMEN1 cells (as compared to DAOY CM); however, recombinant VEGFA alone was insufficient to enhance medulloblastoma cell migration. In addition, bevacizumab, the VEGFA scavenging monoclonal antibody, did not block the migratory phenotype induced by the CM. These results reveal that paracrine factors secreted by meningothelial cells can influence migration and adherence of medulloblastoma tumor cells, but VEGFA may not be a specific target for therapeutic intervention in this context.

Human longevity continues to increase world-wide, often accompanied by decreasing birth rates. As a larger fraction of the population thus gets older, the number of people suffering from disease or disability increases dramatically, presenting a major societal challenge. Healthy ageing has therefore been selected by EU policy makers as an important priority ( http://www.healthyageing.eu/european-policies-and-initiatives ); it benefits not only the elderly but also their direct environment and broader society, as well as the economy. The theme of healthy ageing figures prominently in the Horizon 2020 programme ( https://ec.europa.eu/programmes/horizon2020/en/h2020-section/health-demographic-change-and-wellbeing ), which has launched several research and innovation actions (RIA), like "Understanding health, ageing and disease: determinants, risk factors and pathways" in the work programme on "Personalising healthcare" ( https://ec.europa.eu/research/participants/portal/desktop/en/opportunities/h2020/topics/693-phc-01-2014.html ). Here we present our research proposal entitled "ageing with elegans" (AwE) ( http://www.h2020awe.eu/ ), funded by this RIA, which aims for better understanding of the factors causing health and disease in ageing, and to develop evidence-based prevention, diagnostic, therapeutic and other strategies. The aim of this article, authored by the principal investigators of the 17 collaborating teams, is to describe briefly the rationale, aims, strategies and work packages of AwE for the purposes of sharing our ideas and plans with the biogerontological community in order to invite scientific feedback, suggestions, and criticism.

Overexpression of platelet-derived growth factor receptor alpha (PDGFR-A) has been documented in association with primary tumors and metastasis in medulloblastoma. Tumors from our genetically engineered sonic hedgehog-driven medulloblastoma mouse model overexpress PDGFR-A in primary tumors and thus this mouse model is a good platform with which to study the role of PDGFR-A in this central nervous system malignancy. We hypothesized that inhibition of PDGFR-A in medulloblastoma can slow or inhibit tumor progression in living individuals. To test our hypothesis, we targeted PDGFR-A mediated tumor growth in vitro and in vivo using the tyrosine kinase inhibitor, tandutinib (MLN-518), which strongly inhibits PDGFR-A. Although PDGFR-A inhibition by this agent resulted in reduced mouse tumor cell growth and increased apoptosis in vitro, and reduced tumor cell proliferation in vivo, tandutinib did reduce tumor volume at the doses tested (360 mg/kg) in vivo. Thus, tandutinib may be an agent of interest for sonic hedgehog-driven medulloblastoma if a synergistic drug combination can be identified.

Inhibition of the insulin-like growth factor 1 receptor (Igf1r) is an approach being taken in clinical trials to overcome the dismal outcome for metastatic alveolar rhabdomyosarcoma (ARMS), an aggressive muscle cancer of children and young adults. In our study, we address the potential mechanism(s) of Igf1r inhibitor resistance that might be anticipated for patients. Using a genetically engineered mouse model of ARMS, validated for active Igf1r signaling, we show that the prototypic Igf1r inhibitor NVP-AEW541 can inhibit cell growth and induce apoptosis in vitro in association with decreased Akt and Mapk phosphorylation. However, drug resistance in vivo is more common and is accompanied by Igf1r overexpression, Mapk reactivation, and Her2 overexpression. Her2 is found to form heterodimers with Igf1r in resistant primary tumor cell cultures, and stimulation with Igf2 leads to Her2 phosphorylation. The Her2 inhibitor lapatinib cooperates with NVP-AEW541 to reduce Igf1r phosphorylation and to inhibit cell growth even though lapatinib alone has little effect on growth. These results point to the potential therapeutic importance of simultaneous targeting of Igf1r and Her2 to abrogate resistance. Mol Cancer Ther; 10(4); 697–707. ©2011 AACR.

Genetically engineered mouse models (GEMM) of cancer are of increasing value to preclinical therapeutics. Optical imaging is a cost-effective method of assessing deep-seated tumor growth in GEMMs whose tumors can be encoded to express luminescent or fluorescent reporters, although reporter signal attenuation would be improved if animals were fur-free. In this study, we sought to determine whether hereditable furlessness resulting from a hypomorphic mutation in the Hairless gene would or would not also affect immune competence. By assessing humoral and cellular immunity of the SKH1 mouse line bearing the hypomorphic Hairless mutation, we determined that blood counts, immunoglobulin levels, and CD4+ and CD8+ T cells were comparable between SKH1 and the C57Bl/6 strain. On examination of T-cell subsets, statistically significant differences in naïve T cells (1.7 versus 3.4 × 105 cells/spleen in SKH1 versus C57Bl/6, P = 0.008) and memory T cells (1.4 versus 0.13 × 106 cells/spleen in SKH1 versus C57Bl/6, P = 0.008) were detected. However, the numerical differences did not result in altered T-cell functional response to antigen rechallenge (keyhole limpet hemocyanin) in a lymph node cell in vitro proliferative assay. Furthermore, interbreeding the SKH1 mouse line to a rhabdomyosarcoma GEMM showed preserved antitumor responses of CD56+ natural killer cells and CD163+ macrophages, without any differences in tumor pathology. The fur-free GEMM was also especially amenable to multiplex optical imaging. Thus, SKH1 represents an immune competent, fur-free mouse strain that may be of use for interbreeding to other genetically engineered mouse models of cancer for improved preclinical studies. Mol Cancer Ther; 9(8); 2354–64. ©2010 AACR.

The purpose of this paper is to validate a rapid and cost-effective ex vivo technique, microCT-based virtual histology, as an alternative to MRI imaging for assessing the therapeutic response in genetically engineered mouse models of cancer.All animal procedures were conducted in accordance with the Guidelines for the Care and Use of Laboratory Animals and were approved by the Institutional Animal Care and Use Committee (IACUC) at the University of Texas Health Science Center at San Antonio. MRI imaging was performed on 6-week-old, bortezomib-treated genetically engineered Patched1, p53 mice that recapitulate the characteristics of human medulloblastoma. After MRI scans, the same mice were euthanized to collect brain or spine samples for virtual histology staining followed by microCT scanning.Nine-micrometer resolution ex vivo micro X-ray computed tomography (microCT)-based virtual histology images were qualitatively reflective of high-field live animal images obtained with magnetic resonance imaging (MRI) and histopathology. Cerebellar volumes on microCT-based virtual histology correlated closely with MRI cerebellar volumes (R = 0.998). MRI and microCT-based virtual histology both indicated a significant difference between cerebellar volumes of untreated and treated mice (p = 0.02 and p = 0.04, respectively). The ex vivo microCT method also allowed a 7,430-fold improvement in voxel resolution (voxel volume of 729 μm³ for 9-μm isometric resolution microCT vs. 5,416,800 μm³ for 400 × 111 × 122 μm resolution MRI) at a 28% cost savings ($400 vs. $555 per animal).The ex vivo, en bloc technique of microCT-based virtual histology matched MRI in reflecting histopathology. MicroCT-based virtual histology proved to be a more cost-effective technique and less labor-intensive. On the other hand, MRI provides ability to perform in vivo imaging, faster scanning and lower radiation dose by sacrificing the spatial resolution. Thus, both in vivo MRI and ex vivo microCT-based virtual histology are effective means of quantitatively evaluating therapeutic response in preclinical models of cerebellar tumors including the childhood cancer, medulloblastoma.

The near-infrared wavelengths (700–900 nm) are the most suitable optical window for light penetration and deep tissue imaging in small animals. Herein we report a near-infrared fluorescent contrast agent, crimson carrier, which acts as a blood pool contrast agent to detect and quantify injury and disease in live animals. After determining the excitation–emission spectra and pharmacokinetics, crimson carrier was injected into myoinjured mice to monitor their recovery. Crimson carrier was also used to image transgenic mice with spontaneous tumors. Crimson carrier has maximal excitation and emission wavelengths of 745 nm and 820 nm, respectively. Elimination occurs predominantly via urinary excretion. We demonstrate the utility of this contrast agent for serial imaging of traumatized muscle as well as muscle tumors. The unique long-acting pharmacokinetics and urinary excretion route characteristics make crimson carrier a contrast agent of choice for the visualization of tumors and injured muscle or other tissues in live animal studies. Muscle Nerve, 2010

Medulloblastoma is an aggressive childhood cerebellar tumor. We recently reported a mouse model with conditional deletion of Patched1 gene that recapitulates many characteristics of the human medulloblastoma. Qualitative symptoms observed in the mouse model include irregular stride length, impaired cranial nerve function and decreased motor coordination and performance. In our current study, several quantitative behavioral assays including a mouse rotarod, a forced air challenge, a screen inversion test, a horizontal wire test, and stride length analysis were evaluated to determine the most sensitive and cost-effective functional assay for impaired neuromotor behavior associated with disease progression. Magnetic resonance imaging (MRI) was used to confirm and monitor tumor growth and as an anatomical biomarker for therapeutic response. Wild type mice or medulloblastoma-prone, conditional Patched1 knockout mice were observed by behavioral assays and MRI from postnatal weeks 3–6. Bortezomib treatment was administered during this period and therapeutic response was assessed using cerebellar volumes at the end of treatment. Of the behavioral tests assessed in this study, stride length analysis was best able to detect differences between tumor-prone mice and wild type mice as early as postnatal day 37 (P = 0.003). Significant differences between stride lengths of bortezomib treated and control tumor-bearing mice could be detected as early as postnatal day 42 (P = 0.020). Cerebellar volumes measured by MRI at the end of treatment validated the therapeutic effects seen by behavioral tests (P = 0.03). These findings suggest that stride length analysis may serve as one of the more sensitive and cost-effective method for assessing new therapeutic compounds in this and other preclinical model of brain tumors.

The highly aggressive muscle cancer alveolar rhabdomyosarcoma (ARMS) is one of the most common soft tissue sarcoma of childhood, yet the outcome for the unresectable and metastatic disease is dismal and unchanged for nearly three decades. To better understand the pathogenesis of this disease and to facilitate novel preclinical approaches, we previously developed a conditional mouse model of ARMS by faithfully recapitulating the genetic mutations observed in the human disease, i.e., activation of Pax3:Fkhr fusion gene with either p53 or Cdkn2a inactivation. In this report, we show that this model recapitulates the immunohistochemical profile and the rapid progression of the human disease. We show that Pax3:Fkhr expression increases during late preneoplasia but tumor cells undergoing metastasis are under apparent selection for Pax3:Fkhr expression. At a whole-genome level, a cross-species gene set enrichment analysis and metagene projection study showed that our mouse model is most similar to human ARMS when compared with other pediatric cancers. We have defined an expression profile conserved between mouse and human ARMS, as well as a Pax3:Fkhr signature, including the target gene, SKP2. We further identified 7 “druggable” kinases overexpressed across species. The data affirm the accuracy of this genetically engineered mouse model. [Cancer Res 2009;69(7):2902–11]

Bioluminescent reporter genes are sensitive in situ tools for following disease progression in preclinical models, albeit they are subject to scattering and absorption in deep tissues. We have generated a bicistronic Cre/LoxP reporter mouse line that pairs the expression of firefly luciferase with quantifiable expression of a human placental alkaline phosphatase that is secreted into the serum (SeAP). With the use of this dual-modality bioreporter with a novel, inducible Pax7-CreER line for tracking muscle satellite cells, we demonstrate the longitudinal kinetics of muscle stem cell turnover, accounting for a doubling of the signal from satellite cell and progeny every 3.93 wk in the transition from adolescence to early adulthood. We also show that this dual-modality bioreporter can be incorporated in preclinical cancer models, whereby SeAP activity is reflective of tumor burden. Thus, this dual bioreporter permits both spatial localization and accurate quantification of biological processes in vivo even when the tissue of interest is deep within the animal.—Nishijo, K., Hosoyama, T., Bjornson, C. R. R., Schaffer, B. S., Prajapati, S. I., Bahadur, A. N., Hansen, M. S., Blandford, M. C., McCleish, A. T., Rubin, B. P., Epstein, J. A., Rando, T. A., Capecchi, M. R., Keller, C. Biomarker system for studying muscle, stem cells, and cancer in vivo.

Aging is amenable to intervention and prevention by mild stress-induced hormesis. Previously, we have reported that repeated mild heat stress has antiaging and other beneficial effects on growth and a range of cellular and biochemical characteristics of normal human skin fibroblasts and keratinocytes undergoing aging in vitro. We have also established a model system of sugar-induced premature senescence in human cells, which can be useful for monitoring the protective and hormetic effects of other treatments. We have now initiated studies on testing the hormetic effects of glyoxal and heat shock on the wound-healing capacity of skin fibroblasts and on the angiogenic ability of endothelial cells. The effects of glyoxal on the extent of wound closure in vitro showed a typical biphasic hormetic curve with 20-40% stimulation at lower doses (up to 0.125 mmol) and more than 50% inhibition at concentrations above 0.5 mmol. In the case of angiogenesis by endothelial cells, measured by the standard tube formation assay on Matrigel, a prior exposure to mild heat shock at 41 degrees C for 1 h increased the total tube length and total number of junctions by 30-60% and 10-14%, respectively. In contrast, a severe heat shock at 42.5 degrees C had slightly inhibitory effects on total tube length and the number of junctions. These data add to the ever-growing body of evidence in support of the view that mild stress-induced hormesis can be a useful approach for the modulation, intervention, and prevention of aging and age-related impairments.

Progressive accumulation of molecular damage is a hallmark of cellular aging, which is amenable to intervention and prevention by hormesis through mild stress. Our studies have shown that repeated mild heat stress (RMHS) has antiaging effects on growth and various other cellular and biochemical characteristics of normal human skin fibroblasts undergoing aging in vitro. RMHS at 41 degrees C, for 1 h twice a week, increased the basal levels of various chaperones, reduced the accumulation of oxidatively and glycoxidatively damaged proteins, stimulated proteasomal activities for the degradation of abnormal proteins, improved cellular resistance to ethanol, hydrogen peroxide, and UV-B rays, enhanced the levels of various antioxidant enzymes, and increased the phosphorylation-mediated activities of various stress kinases. RMHS-exposed human fibroblasts are also better protected against glucose- and glyoxal-induced growth inhibition and apoptosis. We have also observed various hormetic effects of RMHS on normal human epidermal keratinocytes, which include increased replicative life span, increased proteasomal activity, and enhanced levels of Na/K-ATPase pump. We are also testing the above effects of RMHS in combination with potential hormetic molecules, such as curcumin, on aging, longevity, and differentiation of human cells in culture.

Cynarin (CYN) is the main derivative of caffeoylquinic acid, found in leaves and heads of artichoke. Potential health-beneficial effects of CYN include as being choloretic-cholesterol lowering, hepatoprotective, anti-atherosclerotic, and antioxidative. We have tested the effects of various doses of CYN on the proliferative potential, survival, morphology, and stress response (SR) markers haemoxygenase-1 (HO-1) and heat shock protein-70 (HSP70) in normal human skin fibroblasts (FSF-1), telomerase-immortalized mesenchymal stem cells (hTERT-MSC) and cervical cancer cells, HeLa. Effects of CYN on cell proliferation and morphology were dose- and cell type-dependent, with 500 µM CYN as the upper limit for all cell types. While the growth and proliferation of cells decreased after exposure to 75 µM CYN for 3 days, overall survival of FSF-1 and hTERT-MSC was higher than that of HeLa cells. Furthermore, CYN induced oxidative SR marker HO-1 in both fibroblasts and stem cells in a biphasic manner, but a slight induction of HSP70 was observed only in the stem cells. Thus, CYN may be useful as a protection against the growth and survival of potentially cancerous cells and may promote longevity of normal cells by induction of SR proteins. Further advanced researches related with CYN and artichoke are recommended.

None of the nutritional components is by itself good or bad, and none of the foodstuffs is either healthy or unhealthy. Nutrition can lead to either good effects or bad effects, and food can have consequences, making us either healthy or unhealthy. It is the quantity, quality, frequency, and emotional satisfaction thatdetermine whether any particular food can help us achieve the aim of maintaining and improving health, and delaying, preventing, or treating a disease

Udgivelsesdato: 2006-May Strategies that lead to the upregulation of the proteasome are known to elicit beneficial consequences to the organism by countering oxidative stress-associated disorders, such as protein conformational diseases, cancer, and aging. Mild treatment with proteasome inhibitors has been previously demonstrated to stimulate proteasome activity and cellular resistance against oxidative injury. However, the mechanism for this action has not been clearly defined. We examined the role of the nuclear factor-E2-related factor 2 (Nrf2) in fibroblasts, a key transactivator of the antioxidant response pathway, in the regulation of the proteasome by its inhibitor MG-132. Here, we demonstrate that the stimulation of the proteasome by low levels of MG-132 can be abrogated by small interfering RNAs (siRNAs) targeted against Nrf2. Consistently, cells that constitutively express Nrf2 exhibit elevated levels of proteasome activities. We further investigate how its beneficial effects, that is, proteasome stimulation, are manifested in young and replicative-senescent cells. Our data underscore that manipulation of Nrf2 by the administration of pharmacologically low levels of proteasome inhibitors may prove to be an alternatively potent strategy for inducing long-term protective effects against oxidative stress.

The phenomenon of hormesis is represented by mild stress-induced stimulation of maintenance and repair pathways resulting in beneficial effects for the cells and organisms. Anti-aging and life-prolonging effects of a wide variety of the so-called stressors, such as pro-oxidants, aldehydes, calorie restriction, irradiation, heat shock, and hypergravity, have been reported. Molecular mechanisms of hormesis due to different stresses are yet to be elucidated, but there are indications that relatively small individual hormetic effects become biologically amplified resulting in the collective significant improvement of cellular and organismic functions and survival. Accepting that some important issues with respect to establishing the optimal hormetic conditions still need to be resolved by future research, hormesis appears to be a promising and effective approach for modulating aging, for preventing or delaying the onset of age-related diseases, and for improving quality of life in old age.

Udgivelsesdato: 2004-null Since aging is primarily the result of a failure of maintenance and repair mechanisms, various approaches are being developed in order to stimulate these pathways and modulate the process of aging. One such approach, termed hormesis, involves challenging cells and organisms by mild stress that often results in anti-aging and life prolonging effects. In a series of experimental studies, 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 beneficial effects of repeated challenge include the 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 other stresses, and enhanced levels of cellular antioxidant ability. In order to elucidate the molecular mechanisms of hormetic effects of RMHS, we are now undertaking studies on signal transduction pathways, energy production and utilisation kinetics, and the proteomic analysis of patterns of proteins synthesised and their posttranslational modifications in various types of human cells undergoing cellular aging in vitro. Human applications of hormesis include early intervention and modulation of the aging process to prevent or delay the onset of age-related conditions, such as sarcopenia, Alzheimer's disease, Parkinson's disease, cataracts and osteoporosis.

N6-furfuryladenine (kinetin) is one of the cytokinin compounds whose anti-aging effects on plants, cultured human skin cells, and fruitflies have been reported. Its chemical structure, natural occurrence, and several biological effects are well documented. Although the exact mechanism of its action is not fully understood, kinetin appears to be a powerful natural antioxidant with pluripotent effects in protecting DNA and protein from oxidative and glyoxidative damage. Further applications of kinetin in health care and biomedicine need to be investigated thoroughly.

Repeated mild heat shock (RMHS) has anti-aging effects on growth and various other cellular and biochemical characteristics of human skin fibroblasts undergoing aging in vitro. In this study, we have tested whether RMHS can reduce the accumulation of heavily damaged proteins, such as oxidized and glycoxidized proteins involved in the development of many pathological consequences of aging. Cultured human skin fibroblasts were subjected to RMHS and were subsequently incubated either with glyoxal (0.1–1 mM) generatingN∈-carboxymethyl-lysine (CML), or withtert-butyl-hydroperoxide (t-BHP 10–700 μM) producing oxidized proteins. About50% more carbonylated-proteins were producedin control cells treated with t-BHP than incells previously exposed to RMHS. More dramatically, a treatment with 0.1 mM glyoxal for 48 h generated CML only in control cells. Such modulation of the level of damaged proteins is most likely related to the beneficial effects of hormesis resulting from exposure to mild stress.

Repeated exposure to mild heat shock (HS) has been shown to induce a wide range of health promoting hormetic effects in various biological systems, including human cells undergoing aging in vitro. In order to understand how cells distinguish between mild and severe stress, we have investigated the extent of early and immediate HS response by analyzing the nuclear translocation of the transcription factor heat shock factor-1 (HSF1), in serially passaged normal adult human facial skin fibroblasts exposed to mild (41 °C) or severe (43 °C) HS. Cells respond differently when exposed to mild and severe HS at different passage levels in terms of the extent of HSF1 translocation. In early passage young cells there was a 5-fold difference between mild and severe HS in the extent of HSF1 translocation. However, in near senescent late passage cells, the difference between mild and severe stress in terms of the extent of HSF1 translocation was reduced to less than 2-fold. One of the reasons for this age-related attenuation of heat shock response is due to the fact there was a higher basal level of HSF1 in the nuclei of late passage cells, which is indicative of increased intrinsic stress during cellular aging. These observations are consistent with previously reported data that whereas repeated mild stress given at younger ages can slow down aging and increase the lifespan, the same level of stress given at older ages may not provide the same benefits. Therefore, elucidating the early and immediate steps in the induction of stress response can be useful in deciding whether a particular level of stress is potentially hormetically beneficial or not.

Single or multiple exposures to mild stress at younger ages often have positive health beneficial effects throughout life, indicating that rescue systems turned on at a young age can be effective even in old age (e.g. Le Bourg 2011). This seems to be at variance with the notion of the so-called trade-offs that due to a limitation of resources it is impossible for an organism to increase all aspects of fitness (see for example, Stearns 2000). Recently, this view has again been raised in an article by McClure et al. (2014), published in Evolution. These authors have reported that Drosophila melanogaster flies challenged by a pretreatment with dead spores of the fungus Metarhizium robertsii lived longer, survived better under heat stress, and had a higher fecundity. Thus, these flies displayed the well-established phenomenon of physiological hormesis (for hormesis terminology, see for example Calabrese et al. 2007; Wiegant 2014). However, McClure et al. (2014) also showed that the pretreatment by dead fungal spores decreased by 10% the survival time of the flies after infection by live spores of the same fungus, and concluded that “when it occurs, hormesis leads to trade-offs with other fitness traits” and that, if applied to human patients, “the consequences of hormetic treatments for infected patients could be dire”. Thus, the balance of positive and negative effects of hormesis on fitness traits could be definitely on the negative side, precluding relying on hormesis in therapy or health maintenance and improvement. In our opinion, this viewpoint is not completely accurate because several other studies performed with flies and other systems show that a mild stress can have positive, negative or no effects on fitness-related traits. For instance, Lints and Le Bourg (1989) showed that female D. melanogaster flies living continuously in hypergravity had a lower and delayed peak of egg-laying, but the total fecundity remained roughly the same. Similarly, Hercus et al. (2003) showed that four rounds of exposure to mild heat stress, which increased the average and maximum lifespan of D. melanogaster and their resistance to heat, slightly reduced egg-laying (about 5%). Growing in hypergravity or having parents living in hypergravity slightly decreased viability of the larvae (Le Bourg and Lints 1989) but, by contrast, living in hypergravity for two weeks, a treatment known to increase longevity of males and resistance to heat in both sexes, had no effect on the number of females inseminated by males (Le Bourg, unpublished results). Regarding resistance to infection by the entomopathogenic fungus Beauveria bassiana, two mild stresses had no effect on post-infection lifespan (hypergravity and heat, Le Bourg et al. 2009), while a pretreatment by cold increased survival in males and had no clear effect in females (e.g. Le Bourg et al. 2009), the result of males being opposite to that of McClure et al. (2014) on immunity. Therefore, these results on traits linked to fitness in a direct (fecundity and viability) or in an indirect way (survival to fungal infection, possibly encountered in the wild) show that mild stresses can have either positive, slightly negative or no effects on these traits. The negative effects, using dead spores of a fungus as a mild stress, reported by McClure et al. (2014), do not pose a serious challenge to the application of hormesis for human health and longevity. However, by pointing out the possible interactive, counteractive or synergistic effects of hormetic interventions, these authors surely address an important aspect of physiological hormesis. Indeed, not all mild stresses increase lifespan and resistance to severe stresses (Lagisz et al. 2013), because the effects on longevity can be sex-specific and mild stresses can decrease resistance to starvation (Le Bourg 2009). Therefore, using hormesis as a possible therapy or a preventive strategy requires, as for any new therapy, testing whether any deleterious consequences of the pretreatment do exist. To give an example in mammals, subjecting a pig to a pretreatment with 250 ppm of carbon monoxide (1000 ppm is lethal) before cardiopulmonary bypass decreases the number of defibrillations necessary to restart the heart (2 vs 6) and prevents cardiac edema (Lavitrano et al. 2004). Obviously, it is necessary to rule out possible deleterious effects of this pretreatment before routinely using it in human cardiac surgery. Other studies have shown that mild stress can mitigate the effects of cardiac and cerebral ischemia (reviews in Simm and Horstkorte 2014; Bejot and Garnier 2014). Since a wide variety of mild stresses, including exercise, have been shown to have health beneficial hormetic effects in various species, including mammals, there is a definitive hope that new strategies relying on hormetic effects could be used either as preventive or as therapeutic in human beings (reviews in Rattan and Le Bourg 2014, but see also, Pardon 2010; Sorensen et al. 2010). It seems that the balance between positive and possible negative effects of mild stress is clearly on the positive side, and any trade-offs in fitness are specific to the general health, robustness and resilience of the body.

Age-related bone loss is thought to be due to impaired osteoblast functions. Insulin-like growth factors (IGFs) have been shown to be important stimulators of bone formation and osteoblast activities in vitro and in vivo. We tested the hypothesis that in vitro osteoblast senescence is associated with changes in components of the IGF-system including IGF-I, IGF-II, IGF-binding proteins (IGFBPs) and IGFBP-specific proteases. We employed a human diploid osteoblast cell line obtained from trabecular bone explants and that exhibit typical characteristics of in vitro senescence during serial subculturing. Using a non-competitive reverse-transcriptase polymerase-chain reaction (RT-PCR) assay, we found that the constitutive level of IGF-I mRNA decreased progressively to 49.9 +/- 4.9% in old osteoblasts as compared to the levels found in the young cells. No age-related change was found in IGF-II steady-state mRNA levels. Changes in IGFBPs gene expression and protein production were assessed using Northern blot analysis and Western ligand blotting (WLB), respectively. IGFBP-3 mRNA levels decreased to 30% and protein production to 16% in aged osteoblasts as compared to levels found in young cells. We also found age-related decreases in mRNA levels of both IGFBP-4 and IGFBP-5 to 70% and 60% in aged osteoblasts, respectively, compared to young cells. While IGFBP-5 protein was not detected by WLB, IGFBP-4 protein production showed a biphasic change with 50% decrease in middle-aged cells and a subsequent increase in aged osteoblasts to levels similar to those in young osteoblasts. We found an age-related increase in the immunoreactive levels of IGFBP-4 protease, however, no detectable IGFBP-4 or IGFBP-3 protease activities in conditioned media from osteoblast cultures were observed. Our findings demonstrate that osteoblast aging is associated with impaired production of the stimulatory components of the IGF-system, that may be a mechanism contributing to age-related decline in osteoblast functions.

Kinetin (N 6 -furfuryladenine) was the first cytokinin to be isolated almost 45 years ago from DNA as an artifactual rearrangement product of the autoclaving process. Since then its chemical structure and properties have been well described. Most importantly, a wide variety of biological effects of kinetin, including those on gene expression, on inhibition of auxin action, on stimulation of calcium flux, on cell cycle, and as an anti-stress and anti-ageing compound have been reported. Recently, views on this very well known plant growth factor have undergone substantial modifications. New data have appeared which show that kinetin is formed in cellular DNA as the product of the oxidative, secondary modification of DNA. Although the biological significance of the endogenous kinetin and the molecular mechanisms of its action are not completely understood at present, most of the experimental data point toward kinetin acting as a strong antioxidant in vitro and in vivo, with potential beneficial uses in agriculture and human healthcare.

The proliferative capacity and cellular and biochemical characteristics of human trabecular bone osteoblasts were analysed throughout their replicative lifespan in vitro. Like several other cell types, human osteoblasts demonstrated a typical Hayflick phenomenon of cellular aging comprising a period of rapid proliferation until cumulative population doubling level (CPDL) 22 to 24, followed by a phase of slow growth and the final cessation of cell division at CPDL 32 to 34. Comparing young cells (less than 20% lifespan completed) and old cells (more than 90% lifespan completed) revealed a progressive increase in population doubling (PD) time, a decrease in attachment frequency, a decrease in the number of S-phase positive cells, a decrease in the rates of DNA, RNA and protein synthesis, an increase in the protein content per cell and an increased proportion of senescence-specific beta-galactosidase positive cells. While osteoblastic production of collagen type I decreased progressively during aging, alkaline phosphatase activity dropped rapidly after the first few passages and then remained constant during the rest of the proliferative lifespan, Significant morphological changes from thin and spindle-shaped early passage young cells to large, flattened and irregularly shaped late passage old cells full of intracellular debris were observed. In comparison, osteoblasts established from an osteoporotic bone sample showed a maximum CPDL of less than 5, had a longer PD time and exhibited abnormal senescent morphology. Thus, we have demonstrated for the first time that human osteoblasts, like several other diploid cell types, have a limited proliferative capacity in vitro and undergo aging and senescence as measured by various cellular and biochemical markers. In addition, preliminary studies show that cells from osteoporotic bone have a severely reduced proliferative capacity. This model of bone cell aging facilitates study of the molecular mechanisms of osteoblast senescence as well as factors related to osteoblast dysfunction in patients with osteoporosis.

Recently, we have reported the presence of kinetin (N6-furfuryladenine) in commercially available DNA, in freshly extracted cellular DNA and in plant cell extracts. We have also found that kinetin has electrochemical properties which can be used for monitoring the level of this modified base in DNA. Here, for the first time, we propose a mechanism for the formation of kinetin in DNA in vivo, based on the analyses of its mass spectra. Since hydroxy radical oxidation at the carbon 5′ of the deoxyribose residue yields furfural, we propose that this aldehyde reacts with the amino group of adenine and, after intramolecular rearrangement, kinetin is formed in vivo. Thus kinetin is the first stable secondary DNA damage product known to date with very well defined cytokinin and anti-aging properties, linked to oxidative processes in the cell. These results also indicate that N6-furfuryladenine or kinetin is an important component of a new salvage pathway of hydroxy radicals constituting a ‘free radical sink’. In this way, the cells can neutralize the harmful properties of hydroxyl radical reaction products, such as furfural, and respond to oxidative stress by inducing defence mechanisms of maintenance and repair.

Advances in imaging technologies and computational capabilities have made possible novel methods for phenotypic assessments and visualization of detailed anatomical structures of whole embryos. We recently reported a rapid and inexpensive technique for achieving high-resolution virtual histology for phenotyping assessment of mouse embryos (Johnson et al., PLoS Genet 2:e61, 2006). By en bloc staining in a solution of electron-dense osmium tetroxide followed by volumetric X-ray computed tomography, whole embryos can be imaged at isometric resolutions as high as 2.5 μm, depending on the size of the specimen. The datasets generated by these techniques are compatible with state-of-the-art computational methods of organ pattern analysis. This method of Microscopic Computed Tomography (microCT)-based Virtual Histology of embryos allows one to rapidly and accurately phenotype transgenic embryos or to engage in developmental and reproductive toxicology studies of investigational drugs at better resolution, less time, and less expense than traditional histology, magnetic resonance microscopy, or the classical Wilson and Staples procedures.

The reactive aldehyde, 4-hydroxynonenal (HNE), is recognized as a product of lipid peroxidation, which binds to macromolecules, in particular proteins. HNE-modified proteins (HNE-MP) have been shown to accumulate during ageing, generally by using polyclonal antibodies, which increase the possibility of detecting false positives. Therefore, we have used a genuine monoclonal antibody specific for HNE-His adducts of proteins/peptides, which were revealed by immunoblotting method for whole-cell HNE-MP measurements in serially passaged human facial skin fibroblasts undergoing ageing in vitro. There was a significant increase in the levels of HNE-MP in serially passaged cells approaching a near senescent state at high passage level (P-61), as compared with low passage level (P-11) young and middle-aged (P-27) cells. However, if the cells were analyzed soon after re-initiation from the frozen samples with little further passaging, the amount of HNE-MP was low even in relatively high passage level (P-37) cells, which is an indication of selective elimination of cells with high molecular damage during the process of thawing and re-initiation in culture. This pilot study on normal human facial skin fibroblasts shows that HNE-MP detection by monoclonal antibody-based dot blot method can be used as a marker for age-related accumulation of lipid peroxidative molecular damage, and could be useful for testing and monitoring the effects of potential skin care products on ageing parameters.

Advanced glycation end-products (AGEs) are a heterogeneous group of compounds formed by the Maillard chemical process of non- enzymatic glycation of free amino groups of proteins, lipids and nucleic acids. This chemical modification of biomolecules is triggered by endogeneous hyperglycaemic or oxidative stress-related processes. Additionally, AGEs can derive from exogenous, mostly diet-related, sources. Considering that AGE accumulation in tissues correlates with ageing and is a hallmark in several age-related diseases it is not surprising that the role of AGEs in ageing and pathology has become increasingly evident. The receptor for AGEs (RAGE) is a single transmembrane protein being expressed in a wide variety of human cells. RAGE binds a broad repertoire of extracellular ligands and mediates responses to stress conditions by activating multiple signal transduction pathways being mostly responsible for acute and/or chronic inflammation. RAGE activation has been implicated in ageing as well as in a number of age-related diseases, including atherosclerosis, neurodegeneration, arthritis, stoke, diabetes and cancer. Here we present a synopsis of findings that relate to AGEs-reported implication in cell signalling pathways and ageing, as well as in pathology. Potential implications and opportunities for translational research and the development of new therapies are also discussed.

The science and study of the biological basis of aging, biogerontology, is now a well-established field with solid scientific base. A paradigm-shift in gerontology has occurred by realising the fact that biological aging occurs in spite of the presence of complex homeodynamic pathways of maintenance, repair and defence, and there is no “enemy within”. This viewpoint separates the modulation of aging from the treatment of one or more age-related diseases. A promising strategy in biogerontology is to slow down aging and to extend healthspan by hormetin-mediated hormesis. Physical, nutritional and mental hormetins, which initiate stress responses and strengthen the homeodynamics, are potentially effective aging modulators. As a biomedical issue, the biological process of aging underlies all major diseases, and while the optimal treatment of every disease is a social and moral necessity, preventing the onset of age-related diseases by intervening in the basic process of aging is the best approach for designing novel pharmaceutical interventions.

Application of hormesis in aging research and interventions is becoming increasingly attractive and successful. The reason for this is the realization that mild stress-induced activation of one or more stress response (SR) pathways, and its consequent stimulation of repair mechanisms, is effective in reducing the age-related accumulation of molecular damage. For example, repeated heat stress-induced synthesis of heat shock proteins has been shown to have a variety of anti-aging effects on growth and other cellular and biochemical characteristics of normal human skin fibroblasts, keratinocytes and endothelial cells undergoing aging in vitro. Therefore, searching for potential hormetins - conditions and compounds eliciting SR-mediated hormesis - is drawing attention of not only the researchers but also the industry involved in developing healthcare products, including nutriceuticals, functional foods and cosmeceuticals. Here we present the example of a skin care cosmetic as one of the first successful product developments incorporating the ideas of hormesis. This was based on the studies to analyse the molecular effects of active ingredients extracted from the roots of the Chinese herb Sanchi (Panax notoginseng) on gene expression at the level of mRNAs and proteins in human skin cells. The results showed that the ginsenosides extracted from Sanchi induced the transcription of stress genes and increased the synthesis of stress proteins, especially the heat shock protein HSP1A1 or Hsp70, in normal human keratinocytes and dermal fibroblasts. Furthermore, this extract also has significant positive effects against facial wrinkles and other symptoms of facial skin aging as tested clinically, which may be due to its hormetic mode of action by stress-induced synthesis of chaperones involved in protein repair and removal of abnormal proteins. Acceptance of such a hormesis-based product by the wider public could be instrumental in the social recognition of the concept of hormesis as the beneficial effects of mild stress of choice, and will encourage the development of novel health care products with physical, nutritional and mental hormetins.

In this study we have measured the caspase-like proteasome activity in individual male and female Drosophila flies by using a non-denaturing lysing technique that consistently extracts total protein. The mean proteasome activity in control C1 females was more than 2 times higher as compared with that in C1 males. However, in longevity-selected LS1 flies the proteasome activity was significantly lower compared to C1 flies, but the sex differences were maintained to some extent. Five other stress resistant lines also had significantly reduced proteasome activity in both sexes. During ageing, there was a progressive decrease in proteasome activity in C1 females, but not in C1 males. This age-related decline in proteasome activity observed in C1 females was not observed in LS1 flies. We conclude that the proteasome activity in controlmale and female flies is significantly different from each other and that increasedlifespan and stress resistance lead to a reduction in proteasome activity and recession of the age-related decline observed in control females.

Summary Aging of human epidermal keratinocytes was studied by serial passaging them as a monolayer culture in a serum-free medium containing 0.09 M calcium. Under these conditions the cells were constantly kept in a proliferative mode and in an undifferentiated state. Aging characteristics in terms of growth and longevity, cumulative population doubling level, cell yield, protein content, and alterations in morphology and in macromolecular synthesis were studied. Furthermore, the induction of differentiation by raising the calcium concentration in the growth medium has facilitated the use of this system to address the issues of the relationship among aging, differentiation and apoptosis in keratinocytes in culture.

Summary Osteoblasts are the bone forming cells, which synthesize and secrete the components of the bone matrix. An imbalance between the breakdown and the build up of bone and a decline in osteoblast activity is considered to be the basis of age-related changes in bone structure and function, including the origin of osteoporosis. In order to determine whether the osteoblast activity decreases because of a decreased proliferative capacity or some other reason, we have examined several cellular and biochemical characteristics of human trabecular osteoblasts serially passaged in culture. We have studied growth and maximum lifespan in terms of cumulative population doubling level achieved in culture. We have also determined changes in morphology, protein content and the synthesis of proteins, DNA and RNA during aging of osteoblasts. Furthermore, changes in the cytoskeletal components actin and microtubuli have been observed along with a comparison of one dimensional and two dimensional gel electrophoretic protein pattern during aging.

Alveolar rhabdomyosarcoma (ARMS) and embryonal rhabdomyosarcoma (ERMS) are among the most common and most treatment resistant soft tissue sarcomas of childhood. Here, we evaluated the potential of (18)F-Fluorodeoxyglucose (FDG) as a marker of therapeutic response to picropodophyllin (PPP), an IGF1R inhibitor, in a conditional mouse model of ARMS and a conditional model of ERMS/undifferentiated pleomorphic sarcoma (UPS).Primary tumor cell cultures from Myf6Cre,Pax3:Fkhr,p53 and Pax7CreER,Ptch1,p53 conditional models of ARMS and ERMS/UPS were found to be highly sensitive to PPP (IC(50) values 150 and 200 nM, respectively). Animals of each model were then treated with 80 mg/kg/day PPP by intraperitoneal injection for 12 days and imaged by (18)F-FDG microPET.Tumor volumes on day 4 for PPP-treated ARMS and ERMS mice were lower than untreated control mouse tumor volumes, although treated tumors were larger than day 0. However, tumor FDG uptake was significantly reduced on day 4 for PPP-treated mice compared to pretreatment baseline or untreated control mice on day 4 (P0.05). Nevertheless, by day 12 tumor volumes and FDG uptake for treated mice had increased significantly, indicating rapidly evolving resistance to therapy.(18)F-FDG PET imaging is a potential imaging biomarker of molecular susceptibility to targeted agents early in treatment for this aggressive form of sarcoma, but may find best use serially for Phase I/II studies where chemotherapy and targeted agents are combined to cytoreduce tumors and abrogate Igf1r inhibitor resistance.

Purpose: Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in childhood. The alveolar subtype of rhabdomyosarcoma (ARMS) is a paradigm for refractory and incurable solid tumors because more than half of the children at diagnosis have either regional lymph node or distant metastases. These studies follow our previous observation that Interleukin-4 receptor α (IL-4Rα) is upregulated in both human and murine ARMS, and that the IL-4R signaling pathway may be a target for abrogating tumor progression. Experimental Design: By in vitro biochemical and cell biology studies as well as preclinical studies using a genetically engineered mouse model, we evaluated the role of IL-4 and IL-13 in IL-4R–mediated mitogenesis, myodifferentiation, and tumor progression. Results: IL-4 and IL-13 ligands accelerated tumor cell growth and activated STAT6, Akt, or MAPK signaling pathways in the human RMS cell lines, RD and Rh30, as well as in mouse primary ARMS cell cultures. IL-4 and IL-13 treatment also decreased protein expression of myogenic differentiation factors MyoD and Myogenin, indicating a loss of muscle differentiation. Using a genetically engineered mouse model of ARMS, we have shown that inhibition of IL-4R signaling pathway with a neutralizing antibody has a profound effect on the frequency of lymph node and pulmonary metastases, resulting in significant survival extension in vivo. Conclusions: Our results indicate that an IL-4R-dependent signaling pathway regulates tumor cell progression in RMS, and inhibition of this pathway could be a promising adjuvant therapeutic approach. Clin Cancer Res; 17(9); 2757–66. ©2011 AACR.

Microscopic computed tomography (microCT) offers high-resolution volumetric imaging of the anatomy of living small animals. However, the contrast between different soft tissues and body fluids is inherently poor in micro-CT images (1). Under these circumstances, visualization of blood vessels becomes a nearly impossible task. To overcome this and to improve the visualization of blood vessels exogenous contrast agents can be used. Herein, we present a methodology for visualizing the vascular network in a rodent model. By using a long-acting aqueous colloidal polydisperse iodinated blood-pool contrast agent, eXIA 160XL, we optimized image acquisition parameters and volume-rendering techniques for finding blood vessels in live animals. Our findings suggest that, to achieve a superior contrast between bone and soft tissue from vessel, multiple-frames (at least 5-8/ frames per view), and 360-720 views (for a full 360° rotation) acquisitions were mandatory. We have also demonstrated the use of a two-dimensional transfer function (where voxel color and opacity was assigned in proportion to CT value and gradient magnitude), in visualizing the anatomy and highlighting the structure of interest, the blood vessel network. This promising work lays a foundation for the qualitative and quantitative assessment of anti-angiogenesis preclinical studies using transgenic or xenograft tumor-bearing mice.

Elongation factors involved in polypeptide chain elongation are considered to be rate limiting for the slowing down of total protein synthesis during ageing. The activities of elongation factors are themselves regulated by various means, including phosphorylation. Here we have compared the activity of a protein kinase, called calcium- and calmodulin-dependent protein kinase III (CaM PK III), specific for the phosphorylation of elongation factor eEF-2, in cell-free extracts prepared from livers isolated from young and old male Fischer 344 rats maintained under freely fed or calorie-restricted dietary regimes. There was a significant increase of more than 70% in the activity of CaM PK III in 24 month old freely fed rat livers as compared with young animals. This age-related increase was found but to a lower extent (46%) in calorie-restricted rats of the same age. Therefore, slowing down of ageing in calorie-restricted animals is also reflected at the level of the regulation of the activity of protein elongation factor eEF-2 by CaM PK III.

Craniofacial defects involving the lip and/or palate are among the most common human birth defects. X-linked cleft palate and ankyloglossia results from loss-of-function mutations in the gene encoding the T-box transcription factor TBX22. Further studies show that TBX22 mutations are also found in around 5% of non-syndromic cleft palate patients. Although palate defects are obvious at birth, the underlying developmental pathogenesis remains unclear. Here, we report a Tbx22(null) mouse, which has a submucous cleft palate (SMCP) and ankyloglossia, similar to the human phenotype, with a small minority showing overt clefts. We also find persistent oro-nasal membranes or, in some mice a partial rupture, resulting in choanal atresia. Each of these defects can cause severe breathing and/or feeding difficulties in the newborn pups, which results in approximately 50% post-natal lethality. Analysis of the craniofacial skeleton demonstrates a marked reduction in bone formation in the posterior hard palate, resulting in the classic notch associated with SMCP. Our results suggest that Tbx22 plays an important role in the osteogenic patterning of the posterior hard palate. Ossification is severely reduced after condensation of the palatal mesenchyme, resulting from a delay in the maturation of osteoblasts. Rather than having a major role in palatal shelf closure, we show that Tbx22 is an important determinant for intramembranous bone formation in the posterior hard palate, which underpins normal palate development and function. These findings could have important implications for the molecular diagnosis in patients with isolated SMCP and/or unexplained choanal atresia.

Scope: Curcumin, a component of the spice turmeric, was tested for its potential hormetic anti-aging effects as an inducer of mild stress. Methods and results: Early passage young human skin fibroblasts treated with low doses of curcumin (below 20μM) showed a time- and concentration-dependent induction of heme oxygenase-1 (HO-1), followed by compensatory increase in glutathione-S-transferase activity, GSH levels and GSH/GSSG ratio. These effects were preceded by induction of oxidative stress (increased levels of reactive oxygen species and DNA damage) and impairment of cells' GSH redox state. Curcumin also induced nuclear factor-erythroid-2-related factor 2 accumulation in the nuclei. The use of the antioxidant N-acetyl cysteine prevented the induction of HO-1 by curcumin. Pharmacological inhibition of phosphatidylinositol 3-kinase, but not other kinases, significantly prevented curcumin-induced HO-1 levels, which was corroborated by the induction of phospho-Akt levels by curcumin. Late passage senescent cells already had higher HO-1 levels, and further induction of HO-1 by curcumin was considerably impaired. The induction of stress responses by curcumin in human cells led to protective hormetic effects to further oxidant challenge. Conclusion: Curcumin induces cellular stress responses in normal human skin fibroblasts through phosphatidylinositol 3-kinase/Akt pathway and redox signaling, supporting the view that curcumin-induced hormetic stimulation of cellular antioxidant defenses can be a useful approach toward anti-aging intervention., União Europeia. Fundo Europeu de Desenvolvimento Regional (FEDER) - programa COMPETE (QREN), Fundação para a Ciência e a Tecnologia (FCT) - bolsa PTDC/QUI-BIQ/101392/2008 (NaturAge)